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Hart SN, Lenin R, Sturgill J, Kern PA, Nikolajczyk B. MITOCHONDRIA-ASSOCIATED MEMBRANES ARE NOT ALTERED IN IMMUNE CELLS IN T2D. bioRxiv 2024:2024.03.25.586170. [PMID: 38585802 PMCID: PMC10996535 DOI: 10.1101/2024.03.25.586170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Metabolism research is increasingly recognizing the contributions of organelle crosstalk to metabolic regulation. Mitochondria-associated membranes (MAMs), which are structures connecting the mitochondria and endoplasmic reticulum (ER), are critical in a myriad of cellular functions linked to cellular metabolism. MAMs control calcium signaling, mitochondrial transport, redox balance, protein folding/degradation, and in some studies, metabolic health. The possibility that MAMs drive changes in cellular function in individuals with Type 2 Diabetes (T2D) is controversial. Although disruptions in MAMs that change the distance between the mitochondria and ER, MAM protein composition, or disrupt downstream signaling, can perpetuate inflammation, one key trait of T2D. However, the full scope of this structure's role in immune cell health and thus T2D-associated inflammation remains unknown. We show that human immune cell MAM proteins and their associated functions are not altered by T2D and thus unlikely to contribute to metaflammation.
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Affiliation(s)
- Samantha N Hart
- Department of Molecular and Cellular Biochemistry, University of Kentucky
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky
| | - Raji Lenin
- Department of Pharmacology and Nutritional Sciences, University of Kentucky
| | - Jamie Sturgill
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky
| | - Philip A Kern
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky
- Department of Internal Medicine, University of Kentucky
| | - Barbara Nikolajczyk
- Department of Pharmacology and Nutritional Sciences, University of Kentucky
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky
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2
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Thomas JM, Kern PA, Bush HM, Robbins SJ, Black WS, Pendergast JS, Clasey JL. Exploring the role of sex in the association of late chronotype on cardiorespiratory fitness. Physiol Rep 2024; 12:e15924. [PMID: 38296465 PMCID: PMC10830391 DOI: 10.14814/phy2.15924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/01/2024] [Accepted: 01/01/2024] [Indexed: 02/05/2024] Open
Abstract
Circadian rhythms differ between young adult males and females. For example, males tend to be later chronotypes, preferring later timing of sleep and activity, than females. Likewise, there are sex differences in body composition and cardiorespiratory fitness. Few studies have investigated the association between circadian rhythms, cardiorespiratory fitness, and body composition. We sought to determine whether chronotype and circadian phase were associated with cardiorespiratory fitness, body composition, and anthropometric measures in sedentary males and females. Fifty-nine adults participated in the study. Circadian phase and chronotype were measured using dim light melatonin onset (DLMO) and the Morningness-Eveningness Questionnaire (MEQ) score. We used peak oxygen uptake (VO2peak ) results from a maximal graded exercise test to assess cardiorespiratory fitness. Body composition, BMI, and circumferences were collected as markers of adiposity. We observed a sex difference in the association between DLMO and VO2peak . For males, a later DLMO was associated with a lower VO2peak . VO2peak did not vary based on DLMO in females. Later circadian phase was also associated with increased body fat percentage, fat mass index, and abdominal circumference in males, but not females. Collectively, these results suggest that males who are later chronotypes may be at risk of obesity and low cardiorespiratory fitness.
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Affiliation(s)
- J. Matthew Thomas
- Department of Kinesiology and Health PromotionUniversity of KentuckyLexingtonKentuckyUSA
- Department of BiologyUniversity of KentuckyLexingtonKentuckyUSA
- Center for Clinical and Translational ScienceUniversity of KentuckyLexingtonKentuckyUSA
- Sanders‐Brown Center on AgingUniversity of KentuckyLexingtonKentuckyUSA
| | - Philip A. Kern
- Center for Clinical and Translational ScienceUniversity of KentuckyLexingtonKentuckyUSA
- The Department of Internal Medicine, Division of EndocrinologyUniversity of KentuckyLexingtonKentuckyUSA
- Barnstable Brown Diabetes CenterUniversity of KentuckyLexingtonKentuckyUSA
| | - Heather M. Bush
- Center for Clinical and Translational ScienceUniversity of KentuckyLexingtonKentuckyUSA
- Department of BiostatisticsUniversity of KentuckyLexingtonKentuckyUSA
| | - Sarah J. Robbins
- Center for Clinical and Translational ScienceUniversity of KentuckyLexingtonKentuckyUSA
- Department of BiostatisticsUniversity of KentuckyLexingtonKentuckyUSA
| | - W. Scott Black
- Department of Kinesiology and Health PromotionUniversity of KentuckyLexingtonKentuckyUSA
- University Health ServiceUniversity of KentuckyLexingtonKentuckyUSA
| | - Julie S. Pendergast
- Department of BiologyUniversity of KentuckyLexingtonKentuckyUSA
- Center for Clinical and Translational ScienceUniversity of KentuckyLexingtonKentuckyUSA
- Barnstable Brown Diabetes CenterUniversity of KentuckyLexingtonKentuckyUSA
- Saha Cardiovascular Research CenterUniversity of KentuckyLexingtonKentuckyUSA
| | - Jody L. Clasey
- Department of Kinesiology and Health PromotionUniversity of KentuckyLexingtonKentuckyUSA
- Center for Clinical and Translational ScienceUniversity of KentuckyLexingtonKentuckyUSA
- Barnstable Brown Diabetes CenterUniversity of KentuckyLexingtonKentuckyUSA
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3
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Long DE, Mantuano AJ, Confides AL, Miller BF, Kern PA, Butterfield TA, Dupont-Versteegden EE. Short-term repeated human biopsy sampling contributes to changes in muscle morphology and higher outcome variability. J Appl Physiol (1985) 2023; 135:1403-1414. [PMID: 37705447 PMCID: PMC10979834 DOI: 10.1152/japplphysiol.00441.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 09/15/2023] Open
Abstract
Changes in skeletal muscle are an important aspect of overall health. The collection of human muscle to study cellular and molecular processes for research requires a needle biopsy procedure which, in itself, can induce changes in the tissue. To investigate the effect of repeat tissue sampling, we collected skeletal muscle biopsy samples from vastus lateralis separated by 7 days. Cellular infiltrate, central nucleation, enlarged extracellular matrix, and rounding of muscle fibers were used as indices to define muscle damage, and we found that 16/26 samples (61.5%) revealed at least two of these symptoms in the secondary biopsy. The presence of damage influenced outcome measures usually obtained in human biopsies. Damaged muscle showed an increase in the number of small fibers even though average fiber and fiber type-specific cross-sectional area (CSA) were not different. This included higher numbers of embryonic myosin heavy chain-positive fibers (P = 0.001) as well as elevated satellite cell number (P = 0.02) in the damaged areas and higher variability in satellite cell count in the total area (P = 0.04). Collagen content was higher in damaged (P = 0.0003) as well as nondamaged areas (P = 0.05) of the muscle sections of the damaged compared with the nondamaged group. Myofibrillar protein and ribonucleic acid (RNA) fractional synthesis rates were not significantly different between the damaged compared with the nondamaged group. Results indicate that common outcomes as well as outcome variability in human muscle tissue are affected by previous biopsies. Therefore, the extent of potential damage should be assessed when performing repeated biopsies.NEW & NOTEWORTHY Indices of damage can be found in repeated biopsy samples of nonintervened control legs. Variables, directly and not directly related to muscle damage or regeneration, were compromised in second biopsy. There is a need to determine potential damage within muscle tissue when repeated muscle sampling is part of the study design. Muscle biopsy sampling may be a source of increased heterogeneity in human muscle data.
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Affiliation(s)
- Douglas E Long
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Alessandra J Mantuano
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Amy L Confides
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Oklahoma City VA Medical Center, Oklahoma City, Oklahoma, United States
| | - Philip A Kern
- Division of Endocrinology, Department of Internal Medicine, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, United States
| | - Timothy A Butterfield
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
- Department of Athletic Training and Clinical Nutrition, College of Health Sciences, University of Kentucky, Lexington, Kentucky, United States
| | - Esther E Dupont-Versteegden
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
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4
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Pape BJ, Kern PA. Two Cases of Surreptitious Steroid Use Uncovered Utilizing Urine Synthetic Glucocorticoid Testing. JCEM Case Rep 2023; 1:luad132. [PMID: 37954833 PMCID: PMC10636495 DOI: 10.1210/jcemcr/luad132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Indexed: 11/14/2023]
Abstract
Although most patients are transparent regarding steroid use, rare patients use steroids surreptitiously, which can occasionally result in factitious Cushing syndrome or extensive diagnostic testing. We present 2 cases, 1 with factitious Cushing syndrome and the second with surreptitious steroid use resulting in abnormal laboratory results and a complicated clinical picture. Synthetic glucocorticoid urine testing was positive for triamcinolone acetonide and fluticasone propionate in case 1 and triamcinolone acetonide only in case 2, which clarified the diagnosis and minimized additional and potentially invasive testing.
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Affiliation(s)
- Bryn J Pape
- Division of Endocrinology, Department of Internal Medicine, University of Kentucky, Lexington, KY 40504, USA
| | - Philip A Kern
- Division of Endocrinology, Department of Internal Medicine, University of Kentucky, Lexington, KY 40504, USA
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5
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Park SH, Helsley RN, Fadhul T, Willoughby JLS, Noetzli L, Tu HC, Solheim MH, Fujisaka S, Pan H, Dreyfuss JM, Bons J, Rose J, King CD, Schilling B, Lusis AJ, Pan C, Gupta M, Kulkarni RN, Fitzgerald K, Kern PA, Divanovic S, Kahn CR, Softic S. Fructose induced KHK-C can increase ER stress independent of its effect on lipogenesis to drive liver disease in diet-induced and genetic models of NAFLD. Metabolism 2023; 145:155591. [PMID: 37230214 PMCID: PMC10752375 DOI: 10.1016/j.metabol.2023.155591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 05/04/2023] [Accepted: 05/10/2023] [Indexed: 05/27/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome, and is estimated to affect one billion individuals worldwide. An increased intake of a high-fat diet (HFD) and sugar-sweetened beverages are risk-factors for NAFLD development, but how their combined intake promotes progression to a more severe form of liver injury is unknown. Here we show that fructose metabolism via ketohexokinase (KHK) C isoform leads to unresolved endoplasmic reticulum (ER) stress when coupled with a HFD intake. Conversely, a liver-specific knockdown of KHK in mice consuming fructose on a HFD is adequate to improve the NAFLD activity score and exert a profound effect on the hepatic transcriptome. Overexpression of KHK-C in cultured hepatocytes is sufficient to induce ER stress in fructose free media. Upregulation of KHK-C is also observed in mice with genetically induced obesity or metabolic dysfunction, whereas KHK knockdown in these mice improves metabolic function. Additionally, in over 100 inbred strains of male or female mice hepatic KHK expression correlates positively with adiposity, insulin resistance, and liver triglycerides. Similarly, in 241 human subjects and their controls, hepatic Khk expression is upregulated in early, but not late stages of NAFLD. In summary, we describe a novel role of KHK-C in triggering ER stress, which offers a mechanistic understanding of how the combined intake of fructose and a HFD propagates the development of metabolic complications.
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Affiliation(s)
- Se-Hyung Park
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Robert N Helsley
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Taghreed Fadhul
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | | | - Leila Noetzli
- Alnylam Pharmaceuticals Inc., Cambridge, MA 02142, USA
| | - Ho-Chou Tu
- Alnylam Pharmaceuticals Inc., Cambridge, MA 02142, USA
| | - Marie H Solheim
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA; Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
| | - Shiho Fujisaka
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA; First Department of Internal Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Hui Pan
- Bioinformatics and Biostatistics Core, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
| | - Jonathan M Dreyfuss
- Bioinformatics and Biostatistics Core, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
| | - Joanna Bons
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Jacob Rose
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Christina D King
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Birgit Schilling
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Aldons J Lusis
- Department of Medicine/Division of Cardiology, Department of Human Genetics, A2-237 Center for the Health Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Calvin Pan
- Department of Medicine/Division of Cardiology, Department of Human Genetics, A2-237 Center for the Health Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Manoj Gupta
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Rohit N Kulkarni
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 02215, USA
| | | | - Philip A Kern
- Department of Medicine, Division of Endocrinology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Senad Divanovic
- Department of Pediatrics, University of Cincinnati College of Medicine, Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - C Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Samir Softic
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA; Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536, USA.
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6
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Park SH, Helsley RN, Fadhul T, Willoughby JL, Noetzli L, Tu HC, Solheim MH, Fujisaka S, Pan H, Dreyfuss JM, Bons J, Rose J, King CD, Schilling B, Lusis AJ, Pan C, Gupta M, Kulkarni RN, Fitzgerald K, Kern PA, Divanovic S, Kahn CR, Softic S. Fructose Induced KHK-C Increases ER Stress and Modulates Hepatic Transcriptome to Drive Liver Disease in Diet-Induced and Genetic Models of NAFLD. bioRxiv 2023:2023.01.27.525605. [PMID: 36747758 PMCID: PMC9900898 DOI: 10.1101/2023.01.27.525605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome, and is estimated to affect one billion individuals worldwide. An increased intake of a high-fat diet (HFD) and sugar-sweetened beverages are risk-factors for NAFLD development, but how their combined intake promotes progression to a more severe form of liver injury is unknown. Here we show that fructose metabolism via ketohexokinase (KHK) C isoform increases endoplasmic reticulum (ER) stress in a dose dependent fashion, so when fructose is coupled with a HFD intake it leads to unresolved ER stress. Conversely, a liver-specific knockdown of KHK in C57BL/6J male mice consuming fructose on a HFD is adequate to improve the NAFLD activity score and exert a profound effect on the hepatic transcriptome. Overexpression of KHK-C in cultured hepatocytes is sufficient to induce ER stress in fructose free media. Upregulation of KHK-C is also observed in genetically obesity ob/ob, db/db and lipodystrophic FIRKO male mice, whereas KHK knockdown in these mice improves metabolic function. Additionally, in over 100 inbred strains of male or female mice hepatic KHK expression correlates positively with adiposity, insulin resistance, and liver triglycerides. Similarly, in 241 human subjects and their controls, hepatic Khk expression is upregulated in early, but not late stages of NAFLD. In summary, we describe a novel role of KHK-C in triggering ER stress, which offers a mechanistic understanding of how the combined intake of fructose and a HFD propagates the development of metabolic complications.
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Affiliation(s)
- Se-Hyung Park
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY. 40536
| | - Robert N. Helsley
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY. 40536
| | - Taghreed Fadhul
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY. 40536
| | | | | | - Ho-Chou Tu
- Alnylam Pharmaceuticals Inc., Cambridge, MA. 02142
| | - Marie H. Solheim
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA. 02215
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
| | - Shiho Fujisaka
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA. 02215
- First Department of Internal Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Hui Pan
- Bioinformatics and Biostatistics Core, Joslin Diabetes Center, Harvard Medical School, Boston, MA
| | - Jonathan M. Dreyfuss
- Bioinformatics and Biostatistics Core, Joslin Diabetes Center, Harvard Medical School, Boston, MA
| | - Joanna Bons
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945
| | - Jacob Rose
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945
| | - Christina D. King
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945
| | - Birgit Schilling
- Proteomics and Aging Center, Buck Institute for Research on Aging, Novato, CA 94945
| | - Aldons J. Lusis
- Department of Medicine/Division of Cardiology, Department of Human Genetics, A2-237 Center for the Health Sciences, University of California, Los Angeles, Los Angeles, CA USA
| | - Calvin Pan
- Department of Medicine/Division of Cardiology, Department of Human Genetics, A2-237 Center for the Health Sciences, University of California, Los Angeles, Los Angeles, CA USA
| | - Manoj Gupta
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center; Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 02215
| | - Rohit N. Kulkarni
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center; Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 02215
| | | | - Philip A. Kern
- Department of Medicine, Division of Endocrinology, University of Kentucky College of Medicine, Lexington, KY. 40536
| | - Senad Divanovic
- Department of Pediatrics, University of Cincinnati College of Medicine, Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229
| | - C. Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA. 02215
| | - Samir Softic
- Department of Pediatrics, Division of Pediatric Gastroenterology, University of Kentucky College of Medicine, Lexington, KY. 40536
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA. 02215
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY. 40536
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Kipp ZA, Xu M, Bates EA, Lee WH, Kern PA, Hinds TD. Bilirubin Levels Are Negatively Correlated with Adiposity in Obese Men and Women, and Its Catabolized Product, Urobilin, Is Positively Associated with Insulin Resistance. Antioxidants (Basel) 2023; 12:antiox12010170. [PMID: 36671031 PMCID: PMC9854555 DOI: 10.3390/antiox12010170] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/03/2023] [Accepted: 01/09/2023] [Indexed: 01/12/2023] Open
Abstract
Bilirubin levels in obese humans and rodents have been shown to be lower than in their lean counterparts. Some studies have proposed that the glucuronyl UGT1A1 enzyme that clears bilirubin from the blood increases in the liver with obesity. UGT1A1 clearance of bilirubin allows more conjugated bilirubin to enter the intestine, where it is catabolized into urobilin, which can be then absorbed via the hepatic portal vein. We hypothesized that when bilirubin levels are decreased, the urobilin increases in the plasma of obese humans, as compared to lean humans. To test this, we measured plasma levels of bilirubin and urobilin, body mass index (BMI), adiposity, blood glucose and insulin, and HOMA IR in a small cohort of obese and lean men and women. We found that bilirubin levels negatively correlated with BMI and adiposity in obese men and women, as compared to their lean counterparts. Contrarily, urobilin levels were positively associated with adiposity and BMI. Only obese women were found to be insulin resistant based on significantly higher HOMA IR, as compared to lean women. The urobilin levels were positively associated with HOMA IR in both groups, but women had a stronger linear correlation. These studies indicate that plasma urobilin levels are associated with obesity and its comorbidities, such as insulin resistance.
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Affiliation(s)
- Zachary A. Kipp
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, 760 Press Avenue, Healthy Kentucky Research Building, Lexington, KY 40508, USA
| | - Mei Xu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, 760 Press Avenue, Healthy Kentucky Research Building, Lexington, KY 40508, USA
| | - Evelyn A. Bates
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, 760 Press Avenue, Healthy Kentucky Research Building, Lexington, KY 40508, USA
| | - Wang-Hsin Lee
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, 760 Press Avenue, Healthy Kentucky Research Building, Lexington, KY 40508, USA
| | - Philip A. Kern
- Department of Internal Medicine, Division of Endocrinology, University of Kentucky, Lexington, KY 40508, USA
| | - Terry D. Hinds
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, 760 Press Avenue, Healthy Kentucky Research Building, Lexington, KY 40508, USA
- Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY 40508, USA
- Markey Cancer Center, University of Kentucky, Lexington, KY 40508, USA
- Correspondence:
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8
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Memetimin H, Zhu B, Lee S, Katz WS, Kern PA, Finlin BS. Improved β-cell function leads to improved glucose tolerance in a transgenic mouse expressing lipoprotein lipase in adipocytes. Sci Rep 2022; 12:22291. [PMID: 36566329 PMCID: PMC9789969 DOI: 10.1038/s41598-022-26995-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 12/22/2022] [Indexed: 12/25/2022] Open
Abstract
Lipoprotein lipase (LPL) hydrolyzes the triglyceride core of lipoproteins and also functions as a bridge, allowing for lipoprotein and cholesterol uptake. Transgenic mice expressing LPL in adipose tissue under the control of the adiponectin promoter (AdipoQ-LPL) have improved glucose metabolism when challenged with a high fat diet. Here, we studied the transcriptional response of the adipose tissue of these mice to acute high fat diet exposure. Gene set enrichment analysis (GSEA) provided mechanistic insight into the improved metabolic phenotype of AdipoQ-LPL mice. First, the cholesterol homeostasis pathway, which is controlled by the SREBP2 transcription factor, is repressed in gonadal adipose tissue AdipoQ-LPL mice. Furthermore, we identified SND1 as a link between SREBP2 and CCL19, an inflammatory chemokine that is reduced in AdipoQ-LPL mice. Second, GSEA identified a signature for pancreatic β-cells in adipose tissue of AdipoQ-LPL mice, an unexpected finding. We explored whether β-cell function is improved in AdipoQ-LPL mice and found that the first phase of insulin secretion is increased in mice challenged with high fat diet. In summary, we identify two different mechanisms for the improved metabolic phenotype of AdipoQ-LPL mice. One involves improved adipose tissue function and the other involves adipose tissue-pancreatic β-cell crosstalk.
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Affiliation(s)
- Hasiyet Memetimin
- grid.266539.d0000 0004 1936 8438Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, KY USA
| | - Beibei Zhu
- grid.266539.d0000 0004 1936 8438Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, KY USA
| | - Sangderk Lee
- grid.266539.d0000 0004 1936 8438Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY USA
| | - Wendy S. Katz
- grid.266539.d0000 0004 1936 8438Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY USA
| | - Philip A. Kern
- grid.266539.d0000 0004 1936 8438Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, KY USA
| | - Brian S. Finlin
- grid.266539.d0000 0004 1936 8438Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, KY USA
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9
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Bruns R, Barton-Baxter M, Poskin R, Kern PA, Stoops WW. Building and implementing a quality assurance/quality improvement program for clinical research. Appl Drug Res Clin Trials Regul Aff 2022; 9:1-8. [PMID: 36619690 PMCID: PMC9815204 DOI: 10.2174/2667337109666220615125134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 03/22/2022] [Accepted: 04/15/2022] [Indexed: 01/12/2023]
Abstract
Background A major goal of the Clinical and Translational Science Award programs is to build and grow clinical and translational research, including the need to ensure that study teams are educated and adhere to best clinical research practices. Objective One of the primary objectives of the Center for Clinical and Translational Science at the University of Kentucky is to help investigators implement standard operating procedures and provide resources to conduct clinical research that is rigorous, ethical and safe. Methods The University of Kentucky Center for Clinical and Translational Science sought to establish a Quality Assurance/Quality Improvement program for Principal Investigator (PI) initiated clinical research studies using Center for Clinical and Translational Science services. Initiated in 2011, this program's goal was to improve research design quality and from the start of the project, "find it, fix it", leading to improved PI education, without being viewed as punitive. Results Since the initiation of our Quality Assurance/Quality Improvement program, PI acceptance has been good and we have expanded its footprint and adjusted our review style to better match the needs of our PIs. This article discusses our experiences with Quality Assurance/Quality Improvement program development and growth. Conclusion A Quality Assurance/Quality Improvement program can be developed that is efficient, effective, educational and well accepted by all clinical research stakeholders.
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Affiliation(s)
- Reva Bruns
- Center for Clinical and Translational Science, University of Kentucky, Lexington KY USA
| | | | - Roxane Poskin
- Center for Clinical and Translational Science, University of Kentucky, Lexington KY USA
| | - Philip A. Kern
- Center for Clinical and Translational Science, University of Kentucky, Lexington KY USA
- Department of Medicine, Division of Endocrinology, University of Kentucky, Lexington KY USA
| | - William W Stoops
- Center for Clinical and Translational Science, University of Kentucky, Lexington KY USA
- Department of Behavioral Science, University of Kentucky, Lexington, KY, USA
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10
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Pugh GH, Fouladvand S, SantaCruz-Calvo S, Agrawal M, Zhang XD, Chen J, Kern PA, Nikolajczyk BS. T cells dominate peripheral inflammation in a cross-sectional analysis of obesity-associated diabetes. Obesity (Silver Spring) 2022; 30:1983-1994. [PMID: 36069294 PMCID: PMC9509440 DOI: 10.1002/oby.23528] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 05/16/2022] [Accepted: 06/07/2022] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Myeloid cells dominate metabolic disease-associated inflammation (metaflammation) in mouse obesity, but the contributions of myeloid cells to the peripheral inflammation that fuels sequelae of human obesity are untested. This study used unbiased approaches to rank contributions of myeloid and T cells to peripheral inflammation in people with obesity across the spectrum of metabolic health. METHODS Peripheral blood mononuclear cells (PBMCs) from people with obesity with or without prediabetes or type 2 diabetes were stimulated with T cell-targeting CD3/CD28 or myeloid-targeting lipopolysaccharide for 20 to 72 hours to assess cytokine production using Bio-Plex. Bioinformatic modeling ranked cytokines with respect to their predictive power for metabolic health. Intracellular tumor necrosis factor α was quantitated as a classical indicator of metaflammation. RESULTS Cytokines increased over 72 hours following T cell-, but not myeloid-, targeted stimulation to indicate that acute myeloid inflammation may shift to T cell inflammation over time. T cells contributed more tumor necrosis factor α to peripheral inflammation regardless of metabolic status. Bioinformatic combination of cytokines from all cohorts, stimuli, and time points indicated that T cell-targeted stimulation was most important for differentiating inflammation in diabetes, consistent with previous identification of a mixed T helper type 1/T helper type 17 cytokine profile in diabetes. CONCLUSIONS T cells dominate peripheral inflammation in obesity; therefore, targeting T cells may be an effective approach for prevention/management of metaflammation.
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Affiliation(s)
- Gabriella H. Pugh
- Department of Microbiology, Immunology, & Molecular
Genetics, University of Kentucky Lexington, Kentucky, USA
| | - Sajjad Fouladvand
- Department of Computer Science, University of Kentucky
Lexington, Kentucky, USA
| | - Sara SantaCruz-Calvo
- Department of Pharmacology and Nutritional Sciences,
University of Kentucky Lexington, Kentucky, USA
| | - Madhur Agrawal
- Department of Pharmacology and Nutritional Sciences,
University of Kentucky Lexington, Kentucky, USA
| | | | - Jin Chen
- Department of Computer Science, University of Kentucky
Lexington, Kentucky, USA
| | - Philip A. Kern
- Department of Internal Medicine, University of Kentucky
Lexington, Kentucky, USA
- Barnstable Brown Diabetes Center, University of Kentucky
Lexington, Kentucky, USA
| | - Barbara S. Nikolajczyk
- Department of Microbiology, Immunology, & Molecular
Genetics, University of Kentucky Lexington, Kentucky, USA
- Department of Pharmacology and Nutritional Sciences,
University of Kentucky Lexington, Kentucky, USA
- Barnstable Brown Diabetes Center, University of Kentucky
Lexington, Kentucky, USA
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11
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Dungan CM, Figueiredo VC, Wen Y, VonLehmden GL, Zdunek CJ, Thomas NT, Mobley CB, Murach KA, Brightwell CR, Long DE, Fry CS, Kern PA, McCarthy JJ, Peterson CA. Senolytic treatment rescues blunted muscle hypertrophy in old mice. GeroScience 2022; 44:1925-1940. [PMID: 35325353 PMCID: PMC9616988 DOI: 10.1007/s11357-022-00542-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/06/2022] [Indexed: 01/07/2023] Open
Abstract
With aging, skeletal muscle plasticity is attenuated in response to exercise. Here, we report that senescent cells, identified using senescence-associated β-galactosidase (SA β-Gal) activity and p21 immunohistochemistry, are very infrequent in resting muscle, but emerge approximately 2 weeks after a bout of resistance exercise in humans. We hypothesized that these cells contribute to blunted hypertrophic potential in old age. Using synergist ablation-induced mechanical overload (MOV) of the plantaris muscle to model resistance training in adult (5-6-month) and old (23-24-month) male C57BL/6 J mice, we found increased senescent cells in both age groups during hypertrophy. Consistent with the human data, there were negligible senescent cells in plantaris muscle from adult and old sham controls, but old mice had significantly more senescent cells 7 and 14 days following MOV relative to young. Old mice had blunted whole-muscle hypertrophy when compared to adult mice, along with smaller muscle fibers, specifically glycolytic type 2x + 2b fibers. To ablate senescent cells using a hit-and-run approach, old mice were treated with vehicle or a senolytic cocktail consisting of 5 mg/kg dasatinib and 50 mg/kg quercetin (D + Q) on days 7 and 10 during 14 days of MOV; control mice underwent sham surgery with or without senolytic treatment. Old mice given D + Q had larger muscles and muscle fibers after 14 days of MOV, fewer senescent cells when compared to vehicle-treated old mice, and changes in the expression of genes (i.e., Igf1, Ddit4, Mmp14) that are associated with hypertrophic growth. Our data collectively show that senescent cells emerge in human and mouse skeletal muscle following a hypertrophic stimulus and that D + Q improves muscle growth in old mice.
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Affiliation(s)
- Cory M Dungan
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.
- Department of Physical Therapy, University of Kentucky, Lexington, KY, USA.
- College of Health Sciences, University of Kentucky, 900 S. Limestone, CTW 445, Lexington, KY, 40536, USA.
| | | | - Yuan Wen
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physical Therapy, University of Kentucky, Lexington, KY, USA
| | | | | | - Nicholas T Thomas
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - C Brooks Mobley
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, KY, USA
- School of Kinesiology, Auburn University, Auburn, AL, USA
| | - Kevin A Murach
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Camille R Brightwell
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Douglas E Long
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physical Therapy, University of Kentucky, Lexington, KY, USA
| | - Christopher S Fry
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Philip A Kern
- Department of Internal Medicine, Division of Endocrinology, University of Kentucky, Lexington, KY, USA
| | - John J McCarthy
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Charlotte A Peterson
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physical Therapy, University of Kentucky, Lexington, KY, USA
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12
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Thiagarajan D, Quadri N, Jawahar S, Zirpoli H, Del Pozo CH, López-Díez R, Hasan SN, Yepuri G, Gugger PF, Finlin BS, Kern PA, Gabbay K, Schmidt AM, Ramasamy R. Aldose reductase promotes diet-induced obesity via induction of senescence in subcutaneous adipose tissue. Obesity (Silver Spring) 2022; 30:1647-1658. [PMID: 35894077 DOI: 10.1002/oby.23496] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 05/09/2022] [Accepted: 05/12/2022] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Aldose reductase (AKR1B1 in humans; Akr1b3 in mice), a key enzyme of the polyol pathway, mediates lipid accumulation in the murine heart and liver. The study objective was to explore potential roles for AKR1B1/Akr1b3 in the pathogenesis of obesity and its complications. METHODS The study employed mice treated with an inhibitor of aldose reductase or mice devoid of Akr1b3 were used to determine their response to a high-fat diet. The study used subcutaneous adipose tissue-derived adipocytes to investigate mechanisms by which AKR1B1/Akr1b3 promotes diet-induced obesity. RESULTS Increased expression of aldose reductase and senescence in the adipose tissue of humans and mice with obesity were demonstrated. Genetic deletion of Akr1b3 or pharmacological blockade of AKRIB3 with zopolrestat reduced high-fat-diet-induced obesity, attenuated markers of adipose tissue senescence, and increased lipolysis. CONCLUSIONS AKR1B1/Akr1b3 modulation of senescence in subcutaneous adipose tissue contributes to aberrant metabolic responses to high-fat feeding. These data unveil new opportunities to target these pathways to combat obesity.
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Affiliation(s)
- Devi Thiagarajan
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
- Saha Cardiovascular Research Center, Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Nosirudeen Quadri
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Shabnam Jawahar
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Hylde Zirpoli
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Carmen Hurtado Del Pozo
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Raquel López-Díez
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Syed Nurul Hasan
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Gautham Yepuri
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Paul F Gugger
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Brian S Finlin
- Center for Clinical and Translational Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A Kern
- Center for Clinical and Translational Sciences, University of Kentucky, Lexington, Kentucky, USA
| | | | - Ann Marie Schmidt
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Ravichandran Ramasamy
- Diabetes Research Program, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
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13
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Conway R, Rockhold JD, SantaCruz-Calvo S, Zukowski E, Pugh GH, Hasturk H, Kern PA, Nikolajczyk BS, Bharath LP. Obesity and Fatty Acids Promote Mitochondrial Translocation of STAT3 Through ROS-Dependent Mechanisms. Front Aging 2022; 3:924003. [PMID: 35928250 PMCID: PMC9344057 DOI: 10.3389/fragi.2022.924003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 06/08/2022] [Indexed: 11/29/2022]
Abstract
Obesity promotes the onset and progression of metabolic and inflammatory diseases such as type 2 diabetes. The chronic low-grade inflammation that occurs during obesity triggers multiple signaling mechanisms that negatively affect organismal health. One such mechanism is the persistent activation and mitochondrial translocation of STAT3, which is implicated in inflammatory pathologies and many types of cancers. STAT3 in the mitochondria (mitoSTAT3) alters electron transport chain activity, thereby influencing nutrient metabolism and immune response. PBMCs and CD4+ T cells from obese but normal glucose-tolerant (NGT) middle-aged subjects had higher phosphorylation of STAT3 on residue serine 727 and more mitochondrial accumulation of STAT3 than cells from lean subjects. To evaluate if circulating lipid overabundance in obesity is responsible for age- and sex-matched mitoSTAT3, cells from lean subjects were challenged with physiologically relevant doses of the saturated and monounsaturated fatty acids, palmitate and oleate, respectively. Fatty acid treatment caused robust accumulation of mitoSTAT3 in all cell types, which was independent of palmitate-induced impairments in autophagy. Co-treatment of cells with fatty acid and trehalose prevented STAT3 phosphorylation and mitochondrial accumulation in an autophagy-independent but cellular peroxide-dependent mechanism. Pharmacological blockade of mitoSTAT3 either by a mitochondria-targeted STAT3 inhibitor or ROS scavenging prevented obesity and fatty acid-induced production of proinflammatory cytokines IL-17A and IL-6, thus establishing a mechanistic link between mitoSTAT3 and inflammatory cytokine production.
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Affiliation(s)
- Rachel Conway
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA, United States
| | - Jack Donato Rockhold
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA, United States
| | - Sara SantaCruz-Calvo
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Emelia Zukowski
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA, United States
| | - Gabriella H. Pugh
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States
| | | | - Philip A. Kern
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
- Department of Medicine, University of Kentucky, Lexington, KY, United States
| | - Barbara S. Nikolajczyk
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Leena P. Bharath
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA, United States
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14
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Thomas JM, Black WS, Kern PA, Pendergast JS, Clasey JL. Heart rate recovery as an assessment of cardiorespiratory fitness in young adults. J Clin Exerc Physiol 2022; 11:44-53. [PMID: 36466304 PMCID: PMC9718361 DOI: 10.31189/2165-6193-11.2.44] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
BACKGROUND Cardiorespiratory fitness, typically measured as peak oxygen uptake (VO2peak) during maximal graded exercise testing (GXTmax), is a predictor of morbidity, mortality, and cardiovascular disease. However, measuring VO2peak is costly and inconvenient and thus not widely used in clinical settings. Alternatively, postexercise heart rate recovery (HRRec), which is an index of vagal reactivation, is a valuable assessment of VO2peak in older adults and athletes. However, the validity of HRRec as a clinical indicator of cardiorespiratory fitness in young, sedentary adults, who are a rapidly growing population at risk for developing obesity and cardiovascular disease, has not been fully elucidated. METHODS We investigated the association between cardiorespiratory fitness, measured by VO2peak (mL·kg-1·min-1), and HRRec measures after a GXTmax in 61 young (25.2 ± 6.1 years), sedentary adults (40 females) using 3 methods. We examined the relationship between VO2peak and absolute (b·min-1) and relative (%) HRRec measures at 1, 2, and 3 min post GXTmax, as well as a measure of the slow component HRRec (HRRec 1 min minus HRR 2 min), using Pearson's correlation analysis. RESULTS VO2peak (36.5 ± 7.9 mL·kg-1·min-1) was not significantly correlated with absolute HRRec at 1 min (r = 0.18), 2 min (r = 0.04) or 3 min (r = 0.01). We also found no significant correlations between VO2peak and relative HRRec at 1 min (r = 0.09), 2 min (r = -0.06) or 3 min (r = -0.10). Lastly, we found no correlation between the measure of the slow component HRRec and VO2peak (r = -0.14). CONCLUSIONS Our results indicate that HRRec measures are not a valid indicator of cardiorespiratory fitness in young, sedentary adults.
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Affiliation(s)
- J. Matthew Thomas
- Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
- Center for Clinical and Translational Science, University of Kentucky, Lexington, Kentucky, USA
| | - W. Scott Black
- Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
- Department of Clinical Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A. Kern
- Center for Clinical and Translational Science, University of Kentucky, Lexington, Kentucky, USA
- The Department of Internal Medicine, Division of Endocrinology, University of Kentucky, Lexington, Kentucky, USA
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Julie S. Pendergast
- Center for Clinical and Translational Science, University of Kentucky, Lexington, Kentucky, USA
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
- Saha Cardiovascular Center, University of Kentucky, Lexington, Kentucky, USA
- Department of Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Jody L. Clasey
- Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
- Center for Clinical and Translational Science, University of Kentucky, Lexington, Kentucky, USA
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
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15
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Long DE, Peck BD, Lavin KM, Dungan CM, Kosmac K, Tuggle SC, Bamman MM, Kern PA, Peterson CA. Skeletal muscle properties show collagen organization and immune cell content are associated with resistance exercise response heterogeneity in older persons. J Appl Physiol (1985) 2022; 132:1432-1447. [PMID: 35482328 DOI: 10.1152/japplphysiol.00025.2022] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In older individuals, hypertrophy from progressive resistance training (PRT) is compromised in approximately one- third of participants in exercise trials. The objective of this study was to establish novel relationships between baseline muscle features and/or their PRT-induced change in vastus lateralis muscle biopsies with hypertrophy outcomes. Multiple linear regression analyses adjusted for sex were performed on phenotypic data from older adults (n=48, 70.8±4.5 years) completing 14 weeks of PRT. Results show that baseline muscle size associates with growth regardless of hypertrophy outcome measure (fiber cross-sectional area (fCSA), β=-0.76, Adj. p<0.01; thigh muscle area by CT, β=-0.75, Adj. p<0.01; DXA thigh lean mass, β=-0.47, Adj. p<0.05). Furthermore, loosely packed collagen organization (β=-0.44, Adj. p<0.05) and abundance of CD11b+/CD206- immune cells (β=-0.36, Adj. p=0.10) were negatively associated with whole muscle hypertrophy, with a significant sex interaction on the latter. Additionally, a composite hypertrophy score generated using all three measures reinforces significant fiber level findings that changes in myonuclei (β=0.67, Adj. p<0.01), changes in immune cells (β=0.48, Adj. p<0.05; both CD11b+/CD206+ and CD11b+/CD206- cells), and capillary density (β=0.56, Adj. p<0.01) are significantly associated with growth. Exploratory single cell RNA-sequencing of CD11b+ cells in muscle in response to resistance exercise showed that macrophages have a mixed phenotype. Collagen associations with macrophages may be an important aspect in muscle response heterogeneity. Detailed histological phenotyping of muscle combined with multiple measures of growth response to resistance training in older persons identify potential new mechanisms underlying response heterogeneity and possible sex differences.
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Affiliation(s)
- Douglas E Long
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Bailey D Peck
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Kaleen M Lavin
- Florida Institute for Human and Machine Cognition, Pensacola, FL, United States
| | - Cory M Dungan
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Kate Kosmac
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Steven Craig Tuggle
- Florida Institute for Human and Machine Cognition, Pensacola, FL, United States.,Center for Exercise Medicine and Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Marcas M Bamman
- Florida Institute for Human and Machine Cognition, Pensacola, FL, United States.,Center for Exercise Medicine and Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Philip A Kern
- Department of Internal Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Charlotte A Peterson
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
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16
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Rosenstein K, Kern PA. Severe Hypercalcemia from Inhalation Pneumonitis via Activation of 1,25 Dihydroxy Vitamin D. J Endocr Soc 2022; 6:bvac066. [PMID: 35528823 PMCID: PMC9070336 DOI: 10.1210/jendso/bvac066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Indexed: 11/23/2022] Open
Abstract
Among the many causes of hypercalcemia are inflammatory conditions, particularly involving granulomatous disease. We present a case of a previously healthy woman who arrived at the emergency department with severe symptomatic hypercalcemia. Workup revealed elevated levels of 1,25-dihydroxyvitamin D along with pneumonitis on computed tomography (CT) imaging. The patient revealed frequent use of eucalyptus oil in her home essential oil diffuser and after removal of the offending agent her hypercalcemia, elevated 1,25-dihydroxyvitamin D, and pneumonitis on CT imaging all resolved.
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Affiliation(s)
- Kyle Rosenstein
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY
| | - Philip A Kern
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY
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17
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Araujo N, Sledziona J, Noothi SK, Burikhanov R, Hebbar N, Ganguly S, Shrestha-Bhattarai T, Zhu B, Katz WS, Zhang Y, Taylor BS, Liu J, Chen L, Weiss HL, He D, Wang C, Morris AJ, Cassis LA, Nikolova-Karakashian M, Nagareddy PR, Melander O, Evers BM, Kern PA, Rangnekar VM. Tumor Suppressor Par-4 Regulates Complement Factor C3 and Obesity. Front Oncol 2022; 12:860446. [PMID: 35425699 PMCID: PMC9004617 DOI: 10.3389/fonc.2022.860446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 02/28/2022] [Indexed: 11/30/2022] Open
Abstract
Prostate apoptosis response-4 (Par-4) is a tumor suppressor that induces apoptosis in cancer cells. However, the physiological function of Par-4 remains unknown. Here we show that conventional Par-4 knockout (Par-4-/-) mice and adipocyte-specific Par-4 knockout (AKO) mice, but not hepatocyte-specific Par-4 knockout mice, are obese with standard chow diet. Par-4-/- and AKO mice exhibit increased absorption and storage of fat in adipocytes. Mechanistically, Par-4 loss is associated with mdm2 downregulation and activation of p53. We identified complement factor c3 as a p53-regulated gene linked to fat storage in adipocytes. Par-4 re-expression in adipocytes or c3 deletion reversed the obese mouse phenotype. Moreover, obese human subjects showed lower expression of Par-4 relative to lean subjects, and in longitudinal studies, low baseline Par-4 levels denoted an increased risk of developing obesity later in life. These findings indicate that Par-4 suppresses p53 and its target c3 to regulate obesity.
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Affiliation(s)
- Nathalia Araujo
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - James Sledziona
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Sunil K Noothi
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States
| | - Ravshan Burikhanov
- Department of Radiation Medicine, University of Kentucky, Lexington, KY, United States
| | - Nikhil Hebbar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Saptadwipa Ganguly
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Tripti Shrestha-Bhattarai
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Beibei Zhu
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Wendy S Katz
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
| | - Yi Zhang
- Department of Computer Science, University of Kentucky, Lexington, KY, United States
| | - Barry S Taylor
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Jinze Liu
- Department of Computer Science, University of Kentucky, Lexington, KY, United States
| | - Li Chen
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Heidi L Weiss
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Daheng He
- Department of Statistics, University of Kentucky, Lexington, KY, United States
| | - Chi Wang
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States.,Department of Biostatistics, University of Kentucky, Lexington, KY, United States
| | - Andrew J Morris
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Lisa A Cassis
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
| | - Mariana Nikolova-Karakashian
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States.,Department of Physiology, University of Kentucky, Lexington, KY, United States
| | | | - Olle Melander
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
| | - B Mark Evers
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States.,Department of Surgery, University of Kentucky, Lexington, KY, United States
| | - Philip A Kern
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Vivek M Rangnekar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States.,Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States.,Department of Radiation Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
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18
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Long DE, Kosmac K, Dungan CM, Bamman MM, Peterson CA, Kern PA. Potential Benefits of Combined Statin and Metformin Therapy on Resistance Training Response in Older Individuals. Front Physiol 2022; 13:872745. [PMID: 35492586 PMCID: PMC9047873 DOI: 10.3389/fphys.2022.872745] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 03/24/2022] [Indexed: 12/24/2022] Open
Abstract
Metformin and statins are currently the focus of large clinical trials testing their ability to counter age-associated declines in health, but recent reports suggest that both may negatively affect skeletal muscle response to exercise. However, it has also been suggested that metformin may act as a possible protectant of statin-related muscle symptoms. The potential impact of combined drug use on the hypertrophic response to resistance exercise in healthy older adults has not been described. We present secondary statin analyses of data from the MASTERS trial where metformin blunted the hypertrophy response in healthy participants (>65 years) following 14 weeks of progressive resistance training (PRT) when compared to identical placebo treatment (n = 94). Approximately one-third of MASTERS participants were taking prescribed statins. Combined metformin and statin resulted in rescue of the metformin-mediated impaired growth response to PRT but did not significantly affect strength. Improved muscle fiber growth may be associated with medication-induced increased abundance of CD11b+/CD206+ M2-like macrophages. Sarcopenia is a significant problem with aging and this study identifies a potential interaction between these commonly used drugs which may help prevent metformin-related blunting of the beneficial effects of PRT.Trial Registration: ClinicalTrials.gov, NCT02308228, Registered on 25 November 2014.
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Affiliation(s)
- Douglas E. Long
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Kate Kosmac
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Cory M. Dungan
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Marcas M. Bamman
- Florida Institute for Human and Machine Cognition, Pensacola, FL, United States
- Center for Exercise Medicine and Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Charlotte A. Peterson
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, United States
| | - Philip A. Kern
- Department of Internal Medicine, Division of Endocrinology, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
- *Correspondence: Philip A. Kern,
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19
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Radulescu A, Dugan AJ, Killian M, Attia SL, Mouzaki M, Fuchs GJ, Kohli R, Bada H, Kern PA, Softic S. Stratification by obesity class, rather than age, can identify a higher percent of children at risk for non-alcoholic fatty liver disease and metabolic dysfunction. Pediatr Obes 2022; 17:e12862. [PMID: 34662928 DOI: 10.1111/ijpo.12862] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 09/04/2021] [Accepted: 09/20/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND An increasing number of clinical practice guidelines recommend screening children with obesity for non-alcoholic fatty liver disease (NAFLD). However, there is limited evidence regarding what parameters should be used to initiate the screening. OBJECTIVE The objective of this study was to determine whether obesity class rather than age group can identify a higher percent of children at risk of NAFLD as assessed by abnormal alanine aminotransferase (ALT). METHODS This is a cross-sectional study in a regional referral clinic for evaluation of obesity. Children were stratified by age group or by obesity class, and data obtained at first visit were analysed. RESULTS Of the 784 children, 482 were ≥10, 209 were 6 to 9 and 93 were 2 to 5 years of age. Abnormal ALT was observed in 32.1%, 46.9% and 61.0% of children with class I, II or III obesity, respectively (p < 0.001), while the risk of abnormal ALT did not differ in very young (2-5), young (6-9), or children older than 10 years. A multivariable analysis showed that class II and class III obesity were associated with 2.1-fold (1.27-3.72) and 4-fold (2.41-6.96) greater odds of abnormal ALT compared with class I obesity. African-American children had lower risk of abnormal ALT (0.27), whereas Hispanic children had higher risk (2.37). Obesity class was a better predictor of abnormal ALT than age, especially in girls. Furthermore, 66.7% of boys (p = 0.009) and 69% of girls (p < 0.001) with abnormal ALT exhibited additional signs of metabolic dysfunction. CONCLUSION Obesity class is more strongly associated with abnormal ALT than age.
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Affiliation(s)
- Aurelia Radulescu
- Department of Pediatrics, University of Kentucky College of Medicine and Kentucky Children's Hospital, Lexington, Kentucky, USA
| | - Adam J Dugan
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Mary Killian
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Suzanna L Attia
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Marialena Mouzaki
- Steatohepatitis Center, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
| | - George J Fuchs
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Rohit Kohli
- Division of Gastroenterology, Hepatology and Nutrition, Children's Hospital Los Angeles, Los Angeles, California, USA
| | - Henrietta Bada
- Department of Pediatrics, University of Kentucky College of Medicine and Kentucky Children's Hospital, Lexington, Kentucky, USA
| | - Philip A Kern
- Department of Medicine, Division of Endocrinology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Samir Softic
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, College of Medicine, University of Kentucky, Lexington, Kentucky, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, USA.,Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
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20
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Kasza I, Kühn JP, Völzke H, Hernando D, Xu YG, Siebert JW, Gibson ALF, Yen CLE, Nelson DW, MacDougald OA, Richardson NE, Lamming DW, Kern PA, Alexander CM. Contrasting recruitment of skin-associated adipose depots during cold challenge of mouse and human. J Physiol 2022; 600:847-868. [PMID: 33724479 PMCID: PMC8443702 DOI: 10.1113/jp280922] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 03/02/2021] [Indexed: 02/03/2023] Open
Abstract
KEY POINTS Several distinct strategies produce and conserve heat to maintain the body temperature of mammals, each associated with unique physiologies, with consequences for wellness and disease susceptibility Highly regulated properties of skin offset the total requirement for heat production We hypothesize that the adipose component of skin is primarily responsible for modulating heat flux; here we evaluate the relative regulation of adipose depots in mouse and human, to test their recruitment to heat production and conservation We found that insulating mouse dermal white adipose tissue accumulates in response to environmentally and genetically induced cool stress; this layer is one of two adipose depots closely apposed to mouse skin, where the subcutaneous mammary gland fat pads are actively recruited to heat production In contrast, the body-wide adipose depot associated with human skin produces heat directly, potentially creating an alternative to the centrally regulated brown adipose tissue ABSTRACT: Mammalian skin impacts metabolic efficiency system-wide, controlling the rate of heat loss and consequent heat production. Here we compare the unique fat depots associated with mouse and human skin, to determine whether they have corresponding functions and regulation. For humans, we assay a skin-associated fat (SAF) body-wide depot to distinguish it from the subcutaneous fat pads characteristic of the abdomen and upper limbs. We show that the thickness of SAF is not related to general adiposity; it is much thicker (1.6-fold) in women than men, and highly subject-specific. We used molecular and cellular assays of β-adrenergic-induced lipolysis and found that dermal white adipose tissue (dWAT) in mice is resistant to lipolysis; in contrast, the body-wide human SAF depot becomes lipolytic, generating heat in response to β-adrenergic stimulation. In mice challenged to make more heat to maintain body temperature (either environmentally or genetically), there is a compensatory increase in thickness of dWAT: a corresponding β-adrenergic stimulation of human skin adipose (in vivo or in explant) depletes adipocyte lipid content. We summarize the regulation of skin-associated adipocytes by age, sex and adiposity, for both species. We conclude that the body-wide dWAT depot of mice shows unique regulation that enables it to be deployed for heat preservation; combined with the actively lipolytic subcutaneous mammary fat pads they enable thermal defence. The adipose tissue that covers human subjects produces heat directly, providing an alternative to the brown adipose tissues.
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Affiliation(s)
- Ildiko Kasza
- McArdle Laboratory for Cancer Research, University of
Wisconsin-Madison, Germany
| | - Jens-Peter Kühn
- Institute and Policlinic of Diagnostic and Interventional
Radiology, Medical Faculty Carl Gustav Carus, Technical University Dresden,
Germany
| | - Henry Völzke
- Institute of Community Medicine, University of Greifswald,
Germany
| | - Diego Hernando
- Department of Radiology, University of Wisconsin-School of
Medicine and Public Health,Department of Medical Physics, University of
Wisconsin-School of Medicine and Public Health
| | - Yaohui G. Xu
- Department of Dermatology, University of Wisconsin-School
of Medicine and Public Health
| | - John W. Siebert
- Department of Surgery, University of Wisconsin-School of
Medicine and Public Health
| | - Angela LF Gibson
- Department of Surgery, University of Wisconsin-School of
Medicine and Public Health
| | - C.-L. Eric Yen
- Department of Nutritional Sciences, University of
Wisconsin-Madison
| | - David W. Nelson
- Department of Nutritional Sciences, University of
Wisconsin-Madison
| | | | - Nicole E. Richardson
- Department of Medicine, University of Wisconsin-School of
Medicine and Public Health,William S. Middleton Memorial Veterans Hospital, Madison,
Wisconsin
| | - Dudley W. Lamming
- Department of Medicine, University of Wisconsin-School of
Medicine and Public Health,William S. Middleton Memorial Veterans Hospital, Madison,
Wisconsin
| | - Philip A. Kern
- Department of Internal Medicine, University of Kentucky,
Lexington
| | - CM Alexander
- McArdle Laboratory for Cancer Research, University of
Wisconsin-Madison, Germany,corresponding author: CM Alexander, McArdle
Laboratory for Cancer Research, University of Wisconsin-Madison, 1111 Highland
Ave, Madison WI 53705-2275. Ph: 608-265 5182;
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21
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Liu R, Pugh GH, Tevonian E, Thompson K, Lauffenburger DA, Kern PA, Nikolajczyk BS. Regulatory T Cells Control Effector T Cell Inflammation in Human Prediabetes. Diabetes 2022; 71:264-274. [PMID: 34737186 PMCID: PMC8914282 DOI: 10.2337/db21-0659] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 11/01/2021] [Indexed: 02/03/2023]
Abstract
A disparate array of plasma/serum markers provides evidence for chronic inflammation in human prediabetes, a condition that is most closely replicated by standard mouse models of obesity and metaflammation. These remain largely nonactionable and contrast with our rich understanding of inflammation in human type 2 diabetes. New data show that inflammatory profiles produced by CD4+ T cells define human prediabetes as a unique inflammatory state. Regulatory T cells (Treg) control mitochondrial function and cytokine production by CD4+ effector T cells (Teff) in prediabetes and type 2 diabetes by supporting T helper (Th)17 or Th1 cytokine production, respectively. These data suggest that Treg control of Teff metabolism regulates inflammation differentially in prediabetes compared with type 2 diabetes. Queries of genes that impact mitochondrial function or pathways leading to transcription of lipid metabolism genes identified the fatty acid importer CD36 as highly expressed in Treg but not Teff from subjects with prediabetes. Pharmacological blockade of CD36 in Treg from subjects with prediabetes decreased Teff production of the Th17 cytokines that differentiate overall prediabetes inflammation. We conclude that Treg control CD4+ T cell cytokine profiles through mechanisms determined, at least in part, by host metabolic status. Furthermore, Treg CD36 uniquely promotes Th17 cytokine production by Teff in prediabetes.
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Affiliation(s)
- Rui Liu
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY
| | - Gabriella H. Pugh
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY
| | - Erin Tevonian
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
| | - Katherine Thompson
- Dr. Bing Zhang Department of Statistics, University of Kentucky, Lexington, KY
| | | | - Philip A. Kern
- Department of Medicine, University of Kentucky, Lexington, KY
- Barnstable Brown Diabetes and Obesity Research Center, University of Kentucky, Lexington, KY
| | - Barbara S. Nikolajczyk
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY
- Barnstable Brown Diabetes and Obesity Research Center, University of Kentucky, Lexington, KY
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY
- Corresponding author: Barbara S. Nikolajczyk,
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22
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Peck BD, Murach KA, Walton RG, Simmons AJ, Long DE, Kosmac K, Dungan CM, Kern PA, Bamman MM, Peterson CA. A muscle cell-macrophage axis involving matrix metalloproteinase 14 facilitates extracellular matrix remodeling with mechanical loading. FASEB J 2022; 36:e22155. [PMID: 35044708 PMCID: PMC8875325 DOI: 10.1096/fj.202100182rr] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 12/10/2021] [Accepted: 12/27/2021] [Indexed: 12/12/2022]
Abstract
The extracellular matrix (ECM) in skeletal muscle plays an integral role in tissue development, structural support, and force transmission. For successful adaptation to mechanical loading, remodeling processes must occur. In a large cohort of older adults, transcriptomics revealed that genes involved in ECM remodeling, including matrix metalloproteinase 14 (MMP14), were the most upregulated following 14 weeks of progressive resistance exercise training (PRT). Using single-cell RNA-seq, we identified macrophages as a source of Mmp14 in muscle following a hypertrophic exercise stimulus in mice. In vitro contractile activity in myotubes revealed that the gene encoding cytokine leukemia inhibitory factor (LIF) is robustly upregulated and can stimulate Mmp14 expression in macrophages. Functional experiments confirmed that modulation of this muscle cell-macrophage axis facilitated Type I collagen turnover. Finally, changes in LIF expression were significantly correlated with MMP14 expression in humans following 14 weeks of PRT. Our experiments reveal a mechanism whereby muscle fibers influence macrophage behavior to promote ECM remodeling in response to mechanical loading.
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Affiliation(s)
- Bailey D Peck
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Kevin A Murach
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - R Grace Walton
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Alexander J Simmons
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Douglas E Long
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Kate Kosmac
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Cory M Dungan
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A Kern
- Division of Endocrinology, Department of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Marcas M Bamman
- UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Charlotte A Peterson
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
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23
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Raj R, Mishra R, Jha N, Joshi V, Correa R, Kern PA. Time in range, as measured by continuous glucose monitor, as a predictor of microvascular complications in type 2 diabetes: a systematic review. BMJ Open Diabetes Res Care 2022; 10:10/1/e002573. [PMID: 34980591 PMCID: PMC8724710 DOI: 10.1136/bmjdrc-2021-002573] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/09/2021] [Indexed: 02/07/2023] Open
Abstract
Continuous glucose monitoring (CGM)-derived time in range (TIR) correlates with hemoglobin A1c (A1c) among patients with type 2 diabetes mellitus (T2DM); however, there is a paucity of data evaluating its association with microvascular complications. We conducted this systematic review to examine the association between TIR and microvascular complications of diabetic retinopathy (DR), diabetic nephropathy (DN), and diabetic peripheral neuropathy (DPN). We conducted a comprehensive literature search on PubMed, Scopus, and Web of Science online databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Full-text original articles that evaluated the association between CGM-derived TIR and risk of microvascular complications and were published between 2010 and June 2021 were included in our systematic review. The quality of the included studies was evaluated using the National Heart, Lung, and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Data were analyzed using qualitative synthesis. Eleven studies on a total of 13 987 patients were included in the systematic review. The median sample size, baseline A1c, and diabetes duration were 466 patients (range: 105-5901), 8.2% (SD 0.5%), and 11.3 years (1.0), respectively. Majority of the studies were conducted in Asia (10 out of 11). Four studies evaluated the relationship between CGM-derived TIR and DR and CGM-derived TIR and DN, while seven studies evaluated the relationship between CGM-derived TIR and DPN. A 10% increase in TIR was associated with a reduction in albuminuria, severity of DR, and prevalence of DPN and cardiac autonomic neuropathy. In addition, an association was observed between urinary albumin to creatinine ratio but not with estimated glomerular filtration rate. This review summarizes recent evidence supporting an association between CGM-derived TIR and microvascular complications among patients with T2DM. A larger-scale multicenter investigation that includes more diverse participants is warranted to further validate the utility of TIR as a predictor of diabetic microvascular complications.
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Affiliation(s)
- Rishi Raj
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Pikeville Medical Center, Pikeville, Kentucky, USA
- Department of Internal Medicine, University of Pikeville Kentucky College of Osteopathic Medicine, Pikeville, Kentucky, USA
| | - Rahul Mishra
- Department of Internal Medicine, Maulana Azad Medical College, New Delhi, Delhi, India
| | - Nivedita Jha
- Department of Internal Medicine, Adichunchanagiri Institute of Medical Sciences, Mandya, Karnataka, India
| | - Vivek Joshi
- Department of Biochemistry and Molecular Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Ricardo Correa
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, The University of Arizona College of Medicine - Phoenix, Phoenix, Arizona, USA
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Phoenix VA Medical Center, Phoenix, Arizona, USA
| | - Philip A Kern
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Kentucky College of Medicine, Lexington, Kentucky, USA
- Barnstable Brown Diabetes Center, University of Kentucky, Lexington, Kentucky, USA
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24
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Smyth SS, Coller BS, Jackson RD, Kern PA, McIntosh S, Meagher EA, Rubio DM, Sandberg K, Tsevat J, Umans JG, Attia J, Baker HL, Nagel JD, McMullen CA, Rosemond E. KL2 scholars' perceptions of factors contributing to sustained translational science career success. J Clin Transl Sci 2021; 6:e34. [PMID: 35433037 PMCID: PMC9003634 DOI: 10.1017/cts.2021.886] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 11/05/2022] Open
Abstract
Introduction Identifying the most effective ways to support career development of early stage investigators in clinical and translational science should yield benefits for the biomedical research community. Institutions with Clinical and Translational Science Awards (CTSA) offer KL2 programs to facilitate career development; however, the sustained impact has not been widely assessed. Methods A survey comprised of quantitative and qualitative questions was sent to 2144 individuals that had previously received support through CTSA KL2 mechanisms. The 547 responses were analyzed with identifying information redacted. Results Respondents held MD (47%), PhD (36%), and MD/PhD (13%) degrees. After KL2 support was completed, physicians' time was divided 50% to research and 30% to patient care, whereas PhD respondents devoted 70% time to research. Funded research effort averaged 60% for the cohort. Respondents were satisfied with their career progression. More than 95% thought their current job was meaningful. Two-thirds felt confident or very confident in their ability to sustain a career in clinical and translational research. Factors cited as contributing to career success included protected time, mentoring, and collaborations. Conclusion This first large systematic survey of KL2 alumni provides valuable insight into the group's perceptions of the program and outcome information. Former scholars are largely satisfied with their career choice and direction, national recognition of their expertise, and impact of their work. Importantly, they identified training activities that contributed to success. Our results and future analysis of the survey data should inform the framework for developing platforms to launch sustaining careers of translational scientists.
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Affiliation(s)
- Susan S. Smyth
- University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | | | | | | | | | | | | | | | - Joel Tsevat
- University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | | | | | - Heather L. Baker
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Joan D. Nagel
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | | | - Erica Rosemond
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
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25
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Finlin BS, Memetimin H, Confides AL, Zhu B, Westgate PM, Dupont-Versteegden EE, Kern PA. Macrophages expressing uncoupling protein 1 increase in adipose tissue in response to cold in humans. Sci Rep 2021; 11:23598. [PMID: 34880313 PMCID: PMC8655049 DOI: 10.1038/s41598-021-03014-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/11/2021] [Indexed: 12/17/2022] Open
Abstract
Acute cold induces beige adipocyte protein marker expression in human subcutaneous white adipose tissue (SC WAT) from both the cold treated and contralateral leg, and the immune system regulates SC WAT beiging in mice. Cold treatment significantly increased the gene expression of the macrophage markers CD68 and 86 in SC WAT. Therefore, we comprehensively investigated the involvement of macrophages in SC WAT beiging in lean and obese humans by immunohistochemistry. Cold treatment significantly increased CD163/CD68 macrophages in SC WAT from the cold treated and contralateral legs of lean and obese subjects, and had similar effects on CD206/CD68 macrophages, whereas the effects on CD86/CD68 macrophages were inconsistent between lean and obese. However, linear regression analysis did not find significant relationships between the change in macrophage numbers and the change in UCP1 protein abundance. A high percentage of CD163 macrophages in SC WAT expressed UCP1, and these UCP1 expressing CD163 macrophages were significantly increased by cold treatment in SC WAT of lean subjects. In conclusion, our results suggest that CD163 macrophages are involved in some aspect of the tissue remodeling that occurs during SC WAT beiging in humans after cold treatment, but they are likely not direct mediators of the beiging process.
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Affiliation(s)
- Brian S Finlin
- The Department of Internal Medicine, Division of Endocrinology, CTW 521, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, 900 S. Limestone St., Lexington, KY, 40536, USA
| | - Hasiyet Memetimin
- The Department of Internal Medicine, Division of Endocrinology, CTW 521, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, 900 S. Limestone St., Lexington, KY, 40536, USA
| | - Amy L Confides
- Department of Rehabilitation Sciences, College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, KY, 40536, USA
| | - Beibei Zhu
- The Department of Internal Medicine, Division of Endocrinology, CTW 521, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, 900 S. Limestone St., Lexington, KY, 40536, USA
| | - Philip M Westgate
- College of Public Health, University of Kentucky, Lexington, KY, 40536, USA
| | - Esther E Dupont-Versteegden
- Department of Rehabilitation Sciences, College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, KY, 40536, USA
| | - Philip A Kern
- The Department of Internal Medicine, Division of Endocrinology, CTW 521, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, 900 S. Limestone St., Lexington, KY, 40536, USA.
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26
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Farmer BC, Williams HC, Devanney NA, Piron MA, Nation GK, Carter DJ, Walsh AE, Khanal R, Young LEA, Kluemper JC, Hernandez G, Allenger EJ, Mooney R, Golden LR, Smith CT, Brandon JA, Gupta VA, Kern PA, Gentry MS, Morganti JM, Sun RC, Johnson LA. APOΕ4 lowers energy expenditure in females and impairs glucose oxidation by increasing flux through aerobic glycolysis. Mol Neurodegener 2021; 16:62. [PMID: 34488832 PMCID: PMC8420022 DOI: 10.1186/s13024-021-00483-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 08/15/2021] [Indexed: 01/21/2023] Open
Abstract
Background Cerebral glucose hypometabolism is consistently observed in individuals with Alzheimer’s disease (AD), as well as in young cognitively normal carriers of the Ε4 allele of Apolipoprotein E (APOE), the strongest genetic predictor of late-onset AD. While this clinical feature has been described for over two decades, the mechanism underlying these changes in cerebral glucose metabolism remains a critical knowledge gap in the field. Methods Here, we undertook a multi-omic approach by combining single-cell RNA sequencing (scRNAseq) and stable isotope resolved metabolomics (SIRM) to define a metabolic rewiring across astrocytes, brain tissue, mice, and human subjects expressing APOE4. Results Single-cell analysis of brain tissue from mice expressing human APOE revealed E4-associated decreases in genes related to oxidative phosphorylation, particularly in astrocytes. This shift was confirmed on a metabolic level with isotopic tracing of 13C-glucose in E4 mice and astrocytes, which showed decreased pyruvate entry into the TCA cycle and increased lactate synthesis. Metabolic phenotyping of E4 astrocytes showed elevated glycolytic activity, decreased oxygen consumption, blunted oxidative flexibility, and a lower rate of glucose oxidation in the presence of lactate. Together, these cellular findings suggest an E4-associated increase in aerobic glycolysis (i.e. the Warburg effect). To test whether this phenomenon translated to APOE4 humans, we analyzed the plasma metabolome of young and middle-aged human participants with and without the Ε4 allele, and used indirect calorimetry to measure whole body oxygen consumption and energy expenditure. In line with data from E4-expressing female mice, a subgroup analysis revealed that young female E4 carriers showed a striking decrease in energy expenditure compared to non-carriers. This decrease in energy expenditure was primarily driven by a lower rate of oxygen consumption, and was exaggerated following a dietary glucose challenge. Further, the stunted oxygen consumption was accompanied by markedly increased lactate in the plasma of E4 carriers, and a pathway analysis of the plasma metabolome suggested an increase in aerobic glycolysis. Conclusions Together, these results suggest astrocyte, brain and system-level metabolic reprogramming in the presence of APOE4, a ‘Warburg like’ endophenotype that is observable in young females decades prior to clinically manifest AD. Supplementary Information The online version contains supplementary material available at 10.1186/s13024-021-00483-y.
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Affiliation(s)
- Brandon C Farmer
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Holden C Williams
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA.,Sanders Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Nicholas A Devanney
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA.,Sanders Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Margaret A Piron
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Grant K Nation
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - David J Carter
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Adeline E Walsh
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Rebika Khanal
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Lyndsay E A Young
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA
| | - Jude C Kluemper
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Gabriela Hernandez
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Elizabeth J Allenger
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Rachel Mooney
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Lesley R Golden
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Cathryn T Smith
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - J Anthony Brandon
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA
| | - Vedant A Gupta
- Gill Heart and Vascular Institute, University of Kentucky, Lexington, KY, USA
| | - Philip A Kern
- Center for Clinical and Translational Science, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Internal Medicine, Division of Endocrinology, University of Kentucky, Lexington, KY, USA
| | - Matthew S Gentry
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA
| | - Josh M Morganti
- Sanders Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Neuroscience, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Ramon C Sun
- Department of Neuroscience, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Lance A Johnson
- Department of Physiology, University of Kentucky College of Medicine, UKMC/MS 609, 800 Rose Street, Lexington, KY, 40536, USA. .,Sanders Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, USA.
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Lavin KM, Bell MB, McAdam JS, Peck BD, Walton RG, Windham ST, Tuggle SC, Long DE, Kern PA, Peterson CA, Bamman MM. Muscle transcriptional networks linked to resistance exercise training hypertrophic response heterogeneity. Physiol Genomics 2021; 53:206-221. [PMID: 33870722 DOI: 10.1152/physiolgenomics.00154.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The skeletal muscle hypertrophic response to resistance exercise training (RT) is highly variable across individuals. The molecular underpinnings of this heterogeneity are unclear. This study investigated transcriptional networks linked to RT-induced muscle hypertrophy, classified as 1) predictive of hypertrophy, 2) responsive to RT independent of muscle hypertrophy, or 3) plastic with hypertrophy. Older adults (n = 31, 18 F/13 M, 70 ± 4 yr) underwent 14-wk RT (3 days/wk, alternating high-low-high intensity). Muscle hypertrophy was assessed by pre- to post-RT change in mid-thigh muscle cross-sectional area (CSA) [computed tomography (CT), primary outcome] and thigh lean mass [dual-energy X-ray absorptiometry (DXA), secondary outcome]. Transcriptome-wide poly-A RNA-seq was performed on vastus lateralis tissue collected pre- (n = 31) and post-RT (n = 22). Prediction networks (using only baseline RNA-seq) were identified by weighted gene correlation network analysis (WGCNA). To identify Plasticity networks, WGCNA change indices for paired samples were calculated and correlated to changes in muscle size outcomes. Pathway-level information extractor (PLIER) was applied to identify Response networks and link genes to biological annotation. Prediction networks (n = 6) confirmed transcripts previously connected to resistance/aerobic training adaptations in the MetaMEx database while revealing novel member genes that should fuel future research to understand the influence of baseline muscle gene expression on hypertrophy. Response networks (n = 6) indicated RT-induced increase in aerobic metabolism and reduced expression of genes associated with spliceosome biology and type-I myofibers. A single exploratory Plasticity network was identified. Findings support that interindividual differences in baseline gene expression may contribute more than RT-induced changes in gene networks to muscle hypertrophic response heterogeneity. Code/Data: https://github.com/kallavin/MASTERS_manuscript/tree/master.
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Affiliation(s)
- Kaleen M Lavin
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama.,Florida Institute for Human and Machine Cognition, Pensacola, Florida
| | - Margaret B Bell
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jeremy S McAdam
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Bailey D Peck
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - R Grace Walton
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Samuel T Windham
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Surgery, The University of Alabama at Birmingham, Birmingham, Alabama
| | - S Craig Tuggle
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Douglas E Long
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Philip A Kern
- Division of Endocrinology, Department of Internal Medicine, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky
| | - Charlotte A Peterson
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Marcas M Bamman
- Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama.,Florida Institute for Human and Machine Cognition, Pensacola, Florida
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28
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Finlin BS, Memetimin H, Zhu B, Confides AL, Vekaria HJ, El Khouli RH, Johnson ZR, Westgate PM, Chen J, Morris AJ, Sullivan PG, Dupont-Versteegden EE, Kern PA. Pioglitazone does not synergize with mirabegron to increase beige fat or further improve glucose metabolism. JCI Insight 2021; 6:143650. [PMID: 33571166 PMCID: PMC8026187 DOI: 10.1172/jci.insight.143650] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 02/10/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Beige and brown adipose tissue (BAT) are associated with improved metabolic homeostasis. We recently reported that the β3-adrenergic receptor agonist mirabegron induced beige adipose tissue in obese insulin-resistant subjects, and this was accompanied by improved glucose metabolism. Here we evaluated pioglitazone treatment with a combination pioglitazone and mirabegron treatment and compared these with previously published data evaluating mirabegron treatment alone. Both drugs were used at FDA-approved dosages. METHODS We measured BAT by PET CT scans, measured beige adipose tissue by immunohistochemistry, and comprehensively characterized glucose and lipid homeostasis and insulin sensitivity by euglycemic clamp and oral glucose tolerance tests. Subcutaneous white adipose tissue, muscle fiber type composition and capillary density, lipotoxicity, and systemic inflammation were evaluated by immunohistochemistry, gene expression profiling, mass spectroscopy, and ELISAs. RESULTS Treatment with pioglitazone or the combination of pioglitazone and mirabegron increased beige adipose tissue protein marker expression and improved insulin sensitivity and glucose homeostasis, but neither treatment induced BAT in these obese subjects. When the magnitude of the responses to the treatments was evaluated, mirabegron was found to be the most effective at inducing beige adipose tissue. Although monotherapy with either mirabegron or pioglitazone induced adipose beiging, combination treatment resulted in less beiging than either alone. The 3 treatments also had different effects on muscle fiber type switching and capillary density. CONCLUSION The addition of pioglitazone to mirabegron treatment does not enhance beiging or increase BAT in obese insulin-resistant research participants. TRIAL REGISTRATION ClinicalTrials.gov NCT02919176. FUNDING NIH DK112282 and P20GM103527 and Clinical and Translational Science Awards grant UL1TR001998.
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Affiliation(s)
- Brian S Finlin
- Division of Endocrinology, Department of Internal Medicine, College of Medicine.,Barnstable Brown Diabetes and Obesity Center
| | - Hasiyet Memetimin
- Division of Endocrinology, Department of Internal Medicine, College of Medicine.,Barnstable Brown Diabetes and Obesity Center
| | - Beibei Zhu
- Division of Endocrinology, Department of Internal Medicine, College of Medicine.,Barnstable Brown Diabetes and Obesity Center
| | - Amy L Confides
- Department of Physical Therapy and Center for Muscle Biology, College of Health Sciences
| | | | | | - Zachary R Johnson
- Division of Endocrinology, Department of Internal Medicine, College of Medicine
| | | | - Jianzhong Chen
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky, USA
| | - Andrew J Morris
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky, USA
| | | | | | - Philip A Kern
- Division of Endocrinology, Department of Internal Medicine, College of Medicine.,Barnstable Brown Diabetes and Obesity Center
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29
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Raj R, Kern PA, Ghanta N, Uy EM, Asadipooya K. Adrenal Vein Cortisol to Metanephrine Ratio for Localizing ACTH-Independent Cortisol-Producing Adenoma: A Case Report. J Endocr Soc 2021; 5:bvab009. [PMID: 33644621 DOI: 10.1210/jendso/bvab009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Indexed: 11/19/2022] Open
Abstract
Context Finding the source of adrenocorticotropic hormone (ACTH)-independent cortisol-producing adenoma in the patients with subclinical Cushing syndrome (SCS) and bilateral adrenal nodules is sometimes challenging. Computed tomography (CT) and positron emission tomography are helpful, but adrenal venous sampling (AVS) is the gold standard approach. However, interpretation of AVS is important to improve the accuracy of decision-making for surgery. We report a case and review of the literature to assess the benefit of using adrenal vein cortisol to metanephrine ratio to determine the source of cortisol production in SCS and bilateral nodules. Evidence Acquisition Three authors searched PubMed for data on patients with SCS who had AVS procedure and measurements of cortisol and catecholamines. Case Description A 51-year-old woman with SCS and hypertension crisis presented to our clinic. Paraclinical investigations revealed that she had an ACTH-independent cortisol-producing adenoma and her CT scan showed bilateral adrenal nodules. After AVS, cortisol (high to low) lateralization ratio could not determine the source of cortisol production but the cortisol to metanephrine ratio localized the source to the left side, which included the larger nodule according to CT measurements. Left adrenalectomy led to clinical and paraclinical improvement. Conclusion There is a possibility of co-secretion of other steroids accompanied with cortisol in the setting of ACTH-independent SCS. Moreover, cortisol measurement alone and interpretation of AVS results based on cortisol values may not help lateralizing the source of cortisol production with bilateral adrenal nodules. Therefore, we suggest applying cortisol to metanephrine ratio with the same gradient (gradient > 2.3, highest to lowest concentration) when the source of cortisol production cannot be determined by cortisol lateralization ratio.
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Affiliation(s)
- Rishi Raj
- Division of Endocrinology, Diabetes, and Metabolism, Department of Internal Medicine, Pikeville Medical Center, Pikeville, KY, USA
| | - Philip A Kern
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA
| | - Neelima Ghanta
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA
| | - Edilfavia M Uy
- Division of Endocrinology, Diabetes, and Metabolism, Department of Internal Medicine, Highlands Appalachian Regional Health Care Medical Center, Prestonsburg, KY, USA
| | - Kamyar Asadipooya
- Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA
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30
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Long DE, Peck BD, Tuggle SC, Villasante Tezanos AG, Windham ST, Bamman MM, Kern PA, Peterson CA, Walton RG. Associations of muscle lipid content with physical function and resistance training outcomes in older adults: altered responses with metformin. GeroScience 2021; 43:629-644. [PMID: 33462708 PMCID: PMC8110673 DOI: 10.1007/s11357-020-00315-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/10/2020] [Indexed: 12/20/2022] Open
Abstract
Preserving muscle mass and strength is critical for long-term health and longevity. Age-related muscle lipid accumulation has been shown to be detrimental to muscle health. In healthy older individuals, we sought to determine whether muscle lipid content, determined from computed tomography, is associated with self-reported physical function, laboratory-measured performance, and the response to progressive resistance training (PRT), and how metformin may alter these responses (N = 46 placebo, 48 metformin). Using multiple linear regression models adjusted for confounders in a large cohort, we show that intermuscular adipose tissue (IMAT) was not associated with baseline function or response to PRT, contrary to previous reports. On the other hand, thigh muscle density (TMD), as an indicator of intra- and extramyocellular lipid (IMCL and EMCL), remained strongly and independently positively associated with physical function and performance following adjustment. Baseline TMD was inversely associated with gains in strength, independent of muscle mass. Percent change in TMD was positively associated with improved chair stand and increased type II fiber frequency but was not associated with muscle hypertrophy or overall strength gain following PRT. For the first time, we show that metformin use during PRT blunted density and strength gains by inhibiting fiber type switching primarily in those with low baseline TMD. These results indicate that participants with higher muscle lipid content derive the most performance benefit from PRT. Our results further indicate that muscle density may be as influential as muscle size for strength, physical function, and performance in healthy older adults. ClinicalTrials.gov , NCT02308228, Registered on 25 November 2014.
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Affiliation(s)
- Douglas E Long
- Department of Physical Therapy and Center for Muscle Biology, University of Kentucky, Charles T. Wethington Bldg., Lexington, KY, 40536-0200, USA.
| | - Bailey D Peck
- Department of Physical Therapy and Center for Muscle Biology, University of Kentucky, Charles T. Wethington Bldg., Lexington, KY, 40536-0200, USA
| | - Steven C Tuggle
- Center for Exercise Medicine and Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Samuel T Windham
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Marcas M Bamman
- Center for Exercise Medicine and Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Philip A Kern
- Department of Internal Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA
| | - Charlotte A Peterson
- Department of Physical Therapy and Center for Muscle Biology, University of Kentucky, Charles T. Wethington Bldg., Lexington, KY, 40536-0200, USA
| | - Rosicka G Walton
- Department of Physical Therapy and Center for Muscle Biology, University of Kentucky, Charles T. Wethington Bldg., Lexington, KY, 40536-0200, USA
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31
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Schoenberg NE, Bowling B, Cardarelli K, Feltner F, Mudd-Martin G, Surratt HL, Kern PA. The Community Leadership Institute of Kentucky (CLIK): A Collaborative Workforce and Leadership Development Program. Prog Community Health Partnersh 2021; 15:95-105. [PMID: 33775965 DOI: 10.1353/cpr.2021.0009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND The Community Leadership Institute of Kentucky (CLIK), a workforce development and leadership program within the Community Engagement and Research Core of the University of Kentucky's Center for Clinical and Translational Science (UK CCTS), was developed to enhance community members' capacity to address pernicious rural health inequities. OBJECTIVES/METHODS In this article, we describe the development, implementation, and results of the program, examining program and project completion rates, quantitative and qualitative evaluations from participants, and professional achievements. RESULTS Based on existing models from other Clinical and Translational Science Awards Programs (CTSAs), CLIK provides diverse programming in a local, supportive setting and supports mentors/academic partners through education and networking. Now in its sixth year, CLIK participants have included 41 leaders from varied local settings, including public school systems, health departments, county and local governments, and other non-profit organizations. Shaped by extensive CLIK participant input, the program offers eleven didactic and hands-on training sessions in evidence-based programming and health promotion; a mentored research project addressing relevant local health inequities; and extensive networking opportunities. CONCLUSIONS CLIK has become an enrichment opportunity for local communities as well as a platform for academic engagement and bi-directional learning. Such community-academic partnerships are particularly needed in traditionally under-resourced rural communities.
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Bharath LP, Agrawal M, McCambridge G, Nicholas DA, Hasturk H, Liu J, Jiang K, Liu R, Guo Z, Deeney J, Apovian CM, Snyder-Cappione J, Hawk GS, Fleeman RM, Pihl RMF, Thompson K, Belkina AC, Cui L, Proctor EA, Kern PA, Nikolajczyk BS. Metformin Enhances Autophagy and Normalizes Mitochondrial Function to Alleviate Aging-Associated Inflammation. Cell Metab 2020; 32:44-55.e6. [PMID: 32402267 PMCID: PMC7217133 DOI: 10.1016/j.cmet.2020.04.015] [Citation(s) in RCA: 295] [Impact Index Per Article: 73.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 01/28/2020] [Accepted: 04/20/2020] [Indexed: 12/20/2022]
Abstract
Age is a non-modifiable risk factor for the inflammation that underlies age-associated diseases; thus, anti-inflammaging drugs hold promise for increasing health span. Cytokine profiling and bioinformatic analyses showed that Th17 cytokine production differentiates CD4+ T cells from lean, normoglycemic older and younger subjects, and mimics a diabetes-associated Th17 profile. T cells from older compared to younger subjects also had defects in autophagy and mitochondrial bioenergetics that associate with redox imbalance. Metformin ameliorated the Th17 inflammaging profile by increasing autophagy and improving mitochondrial bioenergetics. By contrast, autophagy-targeting siRNA disrupted redox balance in T cells from young subjects and activated the Th17 profile by activating the Th17 master regulator, STAT3, which in turn bound IL-17A and F promoters. Mitophagy-targeting siRNA failed to activate the Th17 profile. We conclude that metformin improves autophagy and mitochondrial function largely in parallel to ameliorate a newly defined inflammaging profile that echoes inflammation in diabetes.
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Affiliation(s)
- Leena P Bharath
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA, USA
| | - Madhur Agrawal
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, USA; Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA
| | - Grace McCambridge
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA, USA
| | - Dequina A Nicholas
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Diego, San Diego, CA, USA
| | | | - Jing Liu
- Department of Computer Science, University of Kentucky, Lexington, KY, USA
| | - Kai Jiang
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Rui Liu
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY, USA
| | - Zhenheng Guo
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, USA
| | - Jude Deeney
- Department of Medicine, Endocrinology, Diabetes & Nutrition, Boston University School of Medicine, Boston, MA, USA
| | - Caroline M Apovian
- Department of Medicine, Endocrinology, Diabetes & Nutrition, Boston University School of Medicine, Boston, MA, USA
| | - Jennifer Snyder-Cappione
- Department of Microbiology, Boston University School of Medicine, Boston, MA, USA; Flow Cytometry Core Facility, Boston University School of Medicine, Boston, MA, USA
| | - Gregory S Hawk
- Department of Statistics, University of Kentucky, Lexington, KY, USA
| | - Rebecca M Fleeman
- Departments of Neurosurgery and Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Riley M F Pihl
- Flow Cytometry Core Facility, Boston University School of Medicine, Boston, MA, USA
| | | | - Anna C Belkina
- Flow Cytometry Core Facility, Boston University School of Medicine, Boston, MA, USA; Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Licong Cui
- Department of Computer Science, University of Kentucky, Lexington, KY, USA; School of Biomedical Informatics, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Elizabeth A Proctor
- Departments of Neurosurgery and Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA, USA; Departments of Biomedical Engineering, and Engineering Science & Mechanics and Center for Neural Engineering, Pennsylvania State University, University Park, PA, USA
| | - Philip A Kern
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA; Department of Medicine, University of Kentucky, Lexington, KY, USA
| | - Barbara S Nikolajczyk
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, USA; Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA.
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Long DE, Tuggle SC, Villasante Tezanos AG, Bamman MM, Kern PA, Peterson CA, Walton RG. Associations Of Skeletal Muscle Lipid Infiltration With Hypertrophy And Physical Performance Outcomes In Older Adults. Med Sci Sports Exerc 2020. [DOI: 10.1249/01.mss.0000677540.18974.3b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Finlin BS, Memetimin H, Zhu B, Confides AL, Vekaria HJ, El Khouli RH, Johnson ZR, Westgate PM, Chen J, Morris AJ, Sullivan PG, Dupont-Versteegden EE, Kern PA. The β3-adrenergic receptor agonist mirabegron improves glucose homeostasis in obese humans. J Clin Invest 2020; 130:2319-2331. [PMID: 31961829 PMCID: PMC7190997 DOI: 10.1172/jci134892] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 01/14/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUNDBeige adipose tissue is associated with improved glucose homeostasis in mice. Adipose tissue contains β3-adrenergic receptors (β3-ARs), and this study was intended to determine whether the treatment of obese, insulin-resistant humans with the β3-AR agonist mirabegron, which stimulates beige adipose formation in subcutaneous white adipose tissue (SC WAT), would induce other beneficial changes in fat and muscle and improve metabolic homeostasis.METHODSBefore and after β3-AR agonist treatment, oral glucose tolerance tests and euglycemic clamps were performed, and histochemical analysis and gene expression profiling were performed on fat and muscle biopsies. PET-CT scans quantified brown adipose tissue volume and activity, and we conducted in vitro studies with primary cultures of differentiated human adipocytes and muscle.RESULTSThe clinical effects of mirabegron treatment included improved oral glucose tolerance (P < 0.01), reduced hemoglobin A1c levels (P = 0.01), and improved insulin sensitivity (P = 0.03) and β cell function (P = 0.01). In SC WAT, mirabegron treatment stimulated lipolysis, reduced fibrotic gene expression, and increased alternatively activated macrophages. Subjects with the most SC WAT beiging showed the greatest improvement in β cell function. In skeletal muscle, mirabegron reduced triglycerides, increased the expression of PPARγ coactivator 1 α (PGC1A) (P < 0.05), and increased type I fibers (P < 0.01). Conditioned media from adipocytes treated with mirabegron stimulated muscle fiber PGC1A expression in vitro (P < 0.001).CONCLUSIONMirabegron treatment substantially improved multiple measures of glucose homeostasis in obese, insulin-resistant humans. Since β cells and skeletal muscle do not express β3-ARs, these data suggest that the beiging of SC WAT by mirabegron reduces adipose tissue dysfunction, which enhances muscle oxidative capacity and improves β cell function.TRIAL REGISTRATIONClinicaltrials.gov NCT02919176.FUNDINGNIH: DK112282, P30GM127211, DK 71349, and Clinical and Translational science Awards (CTSA) grant UL1TR001998.
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Affiliation(s)
- Brian S. Finlin
- Division of Endocrinology, Department of Internal Medicine, and
- Barnstable Brown Diabetes and Obesity Center, College of Medicine
| | - Hasiyet Memetimin
- Division of Endocrinology, Department of Internal Medicine, and
- Barnstable Brown Diabetes and Obesity Center, College of Medicine
| | - Beibei Zhu
- Division of Endocrinology, Department of Internal Medicine, and
- Barnstable Brown Diabetes and Obesity Center, College of Medicine
| | - Amy L. Confides
- Department of Physical Therapy, College of Health Sciences
- Center for Muscle Biology
| | | | | | - Zachary R. Johnson
- Division of Endocrinology, Department of Internal Medicine, and
- Barnstable Brown Diabetes and Obesity Center, College of Medicine
| | | | - Jianzhong Chen
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
- Lexington Veterans Affairs Medical Center, Lexington, Kentucky, USA
| | - Andrew J. Morris
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
- Lexington Veterans Affairs Medical Center, Lexington, Kentucky, USA
| | | | | | - Philip A. Kern
- Division of Endocrinology, Department of Internal Medicine, and
- Barnstable Brown Diabetes and Obesity Center, College of Medicine
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Dungan CM, Peck BD, Walton RG, Huang Z, Bamman MM, Kern PA, Peterson CA. In vivo analysis of γH2AX+ cells in skeletal muscle from aged and obese humans. FASEB J 2020; 34:7018-7035. [PMID: 32246795 DOI: 10.1096/fj.202000111rr] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/12/2020] [Accepted: 03/17/2020] [Indexed: 12/25/2022]
Abstract
Over the past 20 years, various identifiers of cellular senescence have been used to quantify the abundance of these cells in different tissues. These include classic markers such as p16, senescence-associated β-gal, and γH2AX, in addition to more recent markers (Sudan Black B and HMGB1). In vivo data on the usefulness of these markers in skeletal muscle are very limited and inconsistent. In the present study, we attempted to identify senescent cells in frozen human skeletal muscle biopsies using these markers to determine the effects of age and obesity on senescent cell burden; however, we were only able to assess the abundance of DNA-damaged nuclei using γH2AX immunohistochemistry. The abundance of γH2AX+ cells, including satellite cells, was not higher in muscle from old compared to young individuals; however, γH2AX+ cells were higher with obesity. Additionally, terminally differentiated, postmitotic myofiber nuclei from obese individuals had elevated γH2AX abundance compared to muscle from lean individuals. Analyses of gene expression support the conclusion that the elevated DNA damage and the senescence-associated secretory phenotype are preferentially associated with obesity in skeletal muscle. These data implicate obesity as a larger contributor to DNA damage in skeletal muscle than aging; however, more sensitive senescence markers for human skeletal muscle are needed to determine if these cells are in fact senescent.
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Affiliation(s)
- Cory M Dungan
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Bailey D Peck
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - R Grace Walton
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Zhengyan Huang
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, KY, USA
| | - Marcas M Bamman
- Department of Cell, Developmental, and Integrative Biology, School of Medicine, University of Alabama, Birmingham, AL, USA.,Geriatric Research, Education, and Clinical Center, Birmingham VA Medical Center, Birmingham, AL, USA
| | - Philip A Kern
- Department of Internal Medicine/Endocrinology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Charlotte A Peterson
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
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Tompkins MG, Bissell BD, Sowders V, Kern PA. Inclusion of adrenal crisis in the differential diagnosis of distributive shock. Am J Health Syst Pharm 2020; 77:415-417. [PMID: 31950137 DOI: 10.1093/ajhp/zxz324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Madeline G Tompkins
- Department of Pharmacy Practice and Science University of Kentucky College of Pharmacy Lexington, KY
| | - Brittany D Bissell
- Department of Pharmacy Practice and Science University of Kentucky College of Pharmacy Lexington, KY.,Department of Pharmacy Services University of Kentucky Albert B. Chandler Hospital Lexington, KY
| | - Virginia Sowders
- Division of Pulmonary and Critical Care Medicine University of Kentucky Albert B. Chandler Hospital Lexington, KY
| | - Philip A Kern
- Department of Internal Medicine Division of Endocrinology University of Kentucky Albert B. Chandler Hospital Lexington, KY
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Thomas JM, Kern PA, Bush HM, McQuerry KJ, Black WS, Clasey JL, Pendergast JS. Circadian rhythm phase shifts caused by timed exercise vary with chronotype. JCI Insight 2020; 5:134270. [PMID: 31895695 DOI: 10.1172/jci.insight.134270] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 12/19/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUNDThe circadian system entrains behavioral and physiological rhythms to environmental cycles, and modern lifestyles disrupt this entrainment. We investigated a timed exercise intervention to phase shift the internal circadian rhythm.METHODSIn 52 young, sedentary adults, dim light melatonin onset (DLMO) was measured before and after 5 days of morning (10 hours after DLMO; n = 26) or evening (20 hours after DLMO; n = 26) exercise. Phase shifts were calculated as the difference in DLMO before and after exercise.RESULTSMorning exercise induced phase advance shifts (0.62 ± 0.18 hours) that were significantly greater than phase shifts from evening exercise (-0.02 ± 0.18 hours; P = 0.01). Chronotype also influenced the effect of timed exercise. For later chronotypes, both morning and evening exercise induced phase advances (0.54 ± 0.29 hours and 0.46 ±0.25 hours, respectively). In contrast, earlier chronotypes had phase advances from morning exercise (0.49 ± 0.25 hours) but had phase delays from evening exercise (-0.41 ± 0.29 hours).CONCLUSIONLate chronotypes - those who experience the most severe circadian misalignment - may benefit from phase advances induced by exercise in the morning or evening, but evening exercise may exacerbate circadian misalignment in early chronotypes. Thus, personalized exercise timing prescription, based on chronotype, could alleviate circadian misalignment in young adults.TRIAL REGISTRATIONTrial registration can be found at www.clinicaltrials.gov (NCT04097886).FUNDINGFunding was supplied by NIH grants UL1TR001998 and TL1TR001997, the Barnstable Brown Diabetes and Obesity Center, the Pediatric Exercise Physiology Laboratory Endowment, the Arvle and Ellen Turner Thacker Research Fund, and the University of Kentucky.
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Affiliation(s)
- J Matthew Thomas
- Department of Kinesiology and Health Promotion.,Center for Clinical and Translational Science
| | - Philip A Kern
- Center for Clinical and Translational Science.,The Department of Internal Medicine, Division of Endocrinology.,Barnstable Brown Diabetes and Obesity Center
| | - Heather M Bush
- Center for Clinical and Translational Science.,Department of Biostatistics
| | | | | | - Jody L Clasey
- Department of Kinesiology and Health Promotion.,Center for Clinical and Translational Science.,Barnstable Brown Diabetes and Obesity Center
| | - Julie S Pendergast
- Center for Clinical and Translational Science.,Barnstable Brown Diabetes and Obesity Center.,Department of Biology, and.,Saha Cardiovascular Research Center, University of Kentucky, Lexington, Kentucky, USA
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Verma N, Liu M, Ly H, Loria A, Campbell KS, Bush H, Kern PA, Jose PA, Taegtmeyer H, Bers DM, Despa S, Goldstein LB, Murray AJ, Despa F. Diabetic microcirculatory disturbances and pathologic erythropoiesis are provoked by deposition of amyloid-forming amylin in red blood cells and capillaries. Kidney Int 2020; 97:143-155. [PMID: 31739987 PMCID: PMC6943180 DOI: 10.1016/j.kint.2019.07.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 07/23/2019] [Accepted: 07/25/2019] [Indexed: 01/11/2023]
Abstract
In the setting of type-2 diabetes, there are declines of structural stability and functionality of blood capillaries and red blood cells (RBCs), increasing the risk for microcirculatory disturbances. Correcting hyperglycemia is not entirely effective at reestablishing normal cellular metabolism and function. Therefore, identification of pathological changes occurring before the development of overt hyperglycemia may lead to novel therapeutic targets for reducing the risk of microvascular dysfunction. Here we determine whether RBC-capillary interactions are altered by prediabetic hypersecretion of amylin, an amyloid forming hormone co-synthesized with insulin, and is reversed by endothelial cell-secreted epoxyeicosatrienoic acids. In patients, we found amylin deposition in RBCs in association with type-2 diabetes, heart failure, cancer and stroke. Amylin-coated RBCs have altered shape and reduced functional (non-glycated) hemoglobin. Amylin-coated RBCs administered intravenously in control rats upregulated erythropoietin and renal arginase expression and activity. We also found that diabetic rats expressing amyloid-forming human amylin in the pancreas (the HIP rat model) have increased tissue levels of hypoxia-inducible transcription factors, compared to diabetic rats that express non-amyloid forming rat amylin (the UCD rat model). Upregulation of erythropoietin correlated with lower hematocrit in the HIP model indicating pathologic erythropoiesis. In the HIP model, pharmacological upregulation of endogenous epoxyeicosatrienoic acids protected the renal microvasculature against amylin deposition and also reduced renal accumulation of HIFs. Thus, prediabetes induces dysregulation of amylin homeostasis and promotes amylin deposition in RBCs and the microvasculature altering RBC-capillary interaction leading to activation of hypoxia signaling pathways and pathologic erythropoiesis. Hence, dysregulation of amylin homeostasis could be a therapeutic target for ameliorating diabetic vascular complications.
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Affiliation(s)
- Nirmal Verma
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Miao Liu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Han Ly
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Analia Loria
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Kenneth S Campbell
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Heather Bush
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A Kern
- Division of Endocrinology, Department of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Pedro A Jose
- Department of Medicine, Division of Renal Diseases and Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Heinrich Taegtmeyer
- Department of Internal Medicine, McGovern Medical School at University of Texas Health, Houston, Texas, USA
| | - Donald M Bers
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Sanda Despa
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Larry B Goldstein
- Department of Neurology, University of Kentucky, Lexington, Kentucky, USA
| | - Andrew J Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Florin Despa
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA; Department of Neurology, University of Kentucky, Lexington, Kentucky, USA.
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Walton RG, Dungan CM, Long DE, Tuggle SC, Kosmac K, Peck BD, Bush HM, Villasante Tezanos AG, McGwin G, Windham ST, Ovalle F, Bamman MM, Kern PA, Peterson CA. Metformin blunts muscle hypertrophy in response to progressive resistance exercise training in older adults: A randomized, double-blind, placebo-controlled, multicenter trial: The MASTERS trial. Aging Cell 2019; 18:e13039. [PMID: 31557380 PMCID: PMC6826125 DOI: 10.1111/acel.13039] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/14/2019] [Accepted: 08/25/2019] [Indexed: 12/25/2022] Open
Abstract
Progressive resistance exercise training (PRT) is the most effective known intervention for combating aging skeletal muscle atrophy. However, the hypertrophic response to PRT is variable, and this may be due to muscle inflammation susceptibility. Metformin reduces inflammation, so we hypothesized that metformin would augment the muscle response to PRT in healthy women and men aged 65 and older. In a randomized, double‐blind trial, participants received 1,700 mg/day metformin (N = 46) or placebo (N = 48) throughout the study, and all subjects performed 14 weeks of supervised PRT. Although responses to PRT varied, placebo gained more lean body mass (p = .003) and thigh muscle mass (p < .001) than metformin. CT scan showed that increases in thigh muscle area (p = .005) and density (p = .020) were greater in placebo versus metformin. There was a trend for blunted strength gains in metformin that did not reach statistical significance. Analyses of vastus lateralis muscle biopsies showed that metformin did not affect fiber hypertrophy, or increases in satellite cell or macrophage abundance with PRT. However, placebo had decreased type I fiber percentage while metformin did not (p = .007). Metformin led to an increase in AMPK signaling, and a trend for blunted increases in mTORC1 signaling in response to PRT. These results underscore the benefits of PRT in older adults, but metformin negatively impacts the hypertrophic response to resistance training in healthy older individuals. ClinicalTrials.gov Identifier: NCT02308228.
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Affiliation(s)
- R. Grace Walton
- Center for Muscle Biology College of Health Sciences University of Kentucky Lexington Kentucky
| | - Cory M. Dungan
- Center for Muscle Biology College of Health Sciences University of Kentucky Lexington Kentucky
| | - Douglas E. Long
- Center for Muscle Biology College of Health Sciences University of Kentucky Lexington Kentucky
| | - S. Craig Tuggle
- UAB Center for Exercise Medicine University of Alabama at Birmingham Birmingham Alabama
| | - Kate Kosmac
- Center for Muscle Biology College of Health Sciences University of Kentucky Lexington Kentucky
| | - Bailey D. Peck
- Center for Muscle Biology College of Health Sciences University of Kentucky Lexington Kentucky
| | - Heather M. Bush
- Department of Biostatistics College of Public Health University of Kentucky Lexington Kentucky
| | | | - Gerald McGwin
- UAB Center for Exercise Medicine University of Alabama at Birmingham Birmingham Alabama
- Department of Epidemiology School of Public Health University of Alabama at Birmingham Birmingham Alabama
| | - Samuel T. Windham
- UAB Center for Exercise Medicine University of Alabama at Birmingham Birmingham Alabama
- Department of Surgery School of Medicine University of Alabama at Birmingham Birmingham Alabama
| | - Fernando Ovalle
- Department of Medicine University of Alabama at Birmingham Birmingham Alabama
| | - Marcas M. Bamman
- UAB Center for Exercise Medicine University of Alabama at Birmingham Birmingham Alabama
- Department of Medicine University of Alabama at Birmingham Birmingham Alabama
- Department of Cell, Developmental & Integrative Biology School of Medicine University of Alabama at Birmingham Birmingham Alabama
| | - Philip A. Kern
- Division of Endocrinology Department of Medicine University of Kentucky Lexington Kentucky
| | - Charlotte A. Peterson
- Center for Muscle Biology College of Health Sciences University of Kentucky Lexington Kentucky
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Li J, Williams MV, Page C, Cassis L, Kern PA, DiPaola RS. The Value of Innovation to Implementation Program (VI 2P): A strategic approach to aligning and leveraging academic research and clinical care missions. Learn Health Syst 2019; 3:e10199. [PMID: 31641687 PMCID: PMC6802527 DOI: 10.1002/lrh2.10199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 04/13/2019] [Accepted: 06/05/2019] [Indexed: 11/12/2022] Open
Abstract
PROBLEM Inefficient implementation of evidence-based care garners increasing attention as a source of suboptimal value of clinical care, and integration of quality improvement methodology into clinical practice represents a potential solution. Academic medical centers (AMCs) often have expertise in implementation science, yet it is not leveraged effectively to solve operational inefficiencies or to rapidly implement evidence-based practices (EBPs). APPROACH To leverage in-house research expertise, the University of Kentucky (UK) College of Medicine and Center for Health Services Research (CHSR) launched a pilot awards program-Value of Innovation to Implementation Program (VI2P)-across its health system and six health professional colleges. Criteria for awards included a transdisciplinary research team and addressing health disparity issues faced by Kentucky. Outcome measures included EBP adoption and implementation and future funding. OUTCOMES The VI2P produced 26 transdisciplinary teams that submitted letters of intent. Ten teams were invited to submit full proposal, and four projects were selected for award, spanning the entire continuum of health-impact research. Three nonawarded projects were implemented and prompted system redesign for an "implementation research living laboratory." A Workgroup for ImplementatioN Science (WINS) was established to forge transdisciplinary teams to pursue federal grant funding yielding proposals totaling $17.17 million submitted, $4.38 million awarded, and $5.97 million under review. Junior faculty were encouraged to pursue implementation science as a research focus. NEXT STEPS UK WINS will continue serve as the hub for dissemination and implementation researchers at UK. On the basis of the enthusiasm expressed by multiple groups and many inquiries about the future training opportunities at UK, we plan to develop a tailored dissemination and implementation (D&I) training program to build research and practice capacity at UK.
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Affiliation(s)
- Jing Li
- University of Kentucky Center for Health Services ResearchLexingtonKentucky
| | - Mark V. Williams
- University of Kentucky Center for Health Services ResearchLexingtonKentucky
| | - Cecilia Page
- EVPHA AdministrationUK HealthCare AdministrationLexingtonKentucky
| | - Lisa Cassis
- University of Kentucky Office of the Vice President for ResearchLexingtonKentucky
| | - Philip A. Kern
- University of Kentucky Center for Clinical and Translational ScienceLexingtonKentucky
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Finlin BS, Zhu B, Boyechko T, Westgate PM, Chia CW, Egan JM, Kern PA. Effect of Rifaximin Treatment on Endotoxemia and Insulin Sensitivity in Humans. J Endocr Soc 2019; 3:1641-1651. [PMID: 31428718 PMCID: PMC6691337 DOI: 10.1210/js.2019-00148] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 06/20/2019] [Indexed: 12/12/2022] Open
Abstract
CONTEXT The gut microbiome is a source of inflammatory factors such as lipopolysaccharide (LPS; endotoxin) that influence metabolic homeostasis. Rifaximin is a well-tolerated antibiotic that may reduce LPS. OBJECTIVE We sought to develop a method to accurately assess postprandial endotoxemia and to determine whether rifaximin treatment improves metabolic homeostasis in obese humans with metabolic syndrome. DESIGN AND SETTING Plasma LPS, adipose inflammation, glucose and lipid metabolism, and insulin sensitivity were evaluated in a clinical research setting. PARTICIPANTS Twelve obese human research participants with prediabetes or three features of metabolic syndrome participated. INTERVENTION The research participants were randomized to placebo control or rifaximin soluble solid dispersion (80 mg/d) treatment groups and treated for 12 weeks. OUTCOME MEASURES We evaluated changes in insulin sensitivity with a euglycemic clamp; changes in lipid and glucose metabolism with oral lipid and glucose tolerance tests; changes in plasma LPS during the lipid tolerance test; and changes in adipose tissue and systemic inflammation by measuring inflammatory cytokines. RESULTS Rifaximin treatment slightly worsened insulin sensitivity (P = 0.03), did not improve glucose or lipid homeostasis, and did not significantly improve adipose tissue inflammation. Our efforts to accurately assess plasma LPS using limulus amebocyte lysate assays revealed that the majority of LPS is masked from detection by limulus amebocyte lysate assays, but can be unmasked using a pretreatment step with protease. Unmasked LPS increases during the lipid tolerance test, but rifaximin treatment did not reduce this. CONCLUSIONS Rifaximin treatment did not lower plasma LPS or improve metabolic homeostasis in obese humans.
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Affiliation(s)
- Brian S Finlin
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky
| | - Beibei Zhu
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky
| | - Tania Boyechko
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky
| | - Philip M Westgate
- College of Public Health, University of Kentucky, Lexington, Kentucky
| | - Chee W Chia
- Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Josephine M Egan
- Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Philip A Kern
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky
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Thomas JM, Pendergast JS, Scott Black W, Kern PA, Clasey JL. Circadian Phase Is Associated With Self-reported Chronotype In Young, Sedentary Adults. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000562257.99480.0b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Agrawal M, Nicholas DA, Proctor EA, Belkina AC, Jones A, Panneerseelan-Bharath L, Raval F, Ip B, Zhu M, Cacicedo J, Habib C, Sainz-Rueda N, Persky L, Sullivan PG, Corkey BE, Apovian CM, Kern PA, Lauffenburger DA, Nikolajczyk BS. Mitochondrial changes synergize with long chain fatty acid derivatives to support Th17 inflammation in diabetes. The Journal of Immunology 2019. [DOI: 10.4049/jimmunol.202.supp.182.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Obesity-associated Type 2 diabetes (T2D) is driven by chronic inflammation. A combinatorial Th17 cytokine profile characterizes and mathematically predicts T2D in people, but the mechanisms that generate the Th17 profile are not clear. We tested the possibility that anaerobic glycolysis, which fuels inflammatory cytokine production from multiple immune cell types, drives the T2D-associated Th17 profile. We showed that activated PBMCs and purified CD4+T cells from T2D subjects prefer anaerobic glucose metabolism to produce ATP regardless of fuel availability. Unexpectedly, glucose starvation did not abrogate the T2D-predictive Th17 profile. Gene expression array suggested that mitochondrial fatty acid uptake catalyzing protein CPT1a differentiated PBMCs from T2D and ND subjects. CPT1a inhibition by etomoxir strongly down-regulated the Th17 profile, surprisingly independent of CPT1a-mediated fatty acid oxidation (OXPHOS). These data suggest that OXPHOS-independent mitochondrial changes that are also glucose-independent support the Th17 profile in T2D. Analyses from T2D vs ND PBMCs showed a lower CACT:CPT1a protein ratio in T2D, indicating defects in lipid uptake and thus defects in lipid flux. We knocked down CACT protein and overloaded PBMCs from lean subjects with fatty acylcarnitines to mimic lipid uptake defects in T2D. 16C-fatty acylcarnitine, but not 6C- or 10C-derivatives, increased frequency of CD4+IL-17+T cells, and phenocopied the Th17 profile only in CACT knockdown cells. 16C-fatty acylcarnitine alone had no effect. We conclude that excessive long chain fatty acylcarnitine combines with dysfunctional mitochondria to support a T2D-associated Th17 profile largely independent of glycolysis.
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McCambridge G, Agrawal M, Keady A, Kern PA, Hasturk H, Nikolajczyk BS, Bharath LP. Saturated Fatty Acid Activates T Cell Inflammation Through a Nicotinamide Nucleotide Transhydrogenase (NNT)-Dependent Mechanism. Biomolecules 2019; 9:biom9020079. [PMID: 30823587 PMCID: PMC6406569 DOI: 10.3390/biom9020079] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/19/2019] [Accepted: 02/19/2019] [Indexed: 01/17/2023] Open
Abstract
Circulating fatty acids (FAs) increase with obesity and can drive mitochondrial damage and inflammation. Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial protein that positively regulates nicotinamide adenine dinucleotide phosphate (NADPH), a key mediator of energy transduction and redox homeostasis. The role that NNT-regulated bioenergetics play in the inflammatory response of immune cells in obesity is untested. Our objective was to determine how free fatty acids (FFAs) regulate inflammation through impacts on mitochondria and redox homeostasis of peripheral blood mononuclear cells (PBMCs). PBMCs from lean subjects were activated with a T cell-specific stimulus in the presence or absence of generally pro-inflammatory palmitate and/or non-inflammatory oleate. Palmitate decreased immune cell expression of NNT, NADPH, and anti-oxidant glutathione, but increased reactive oxygen and proinflammatory Th17 cytokines. Oleate had no effect on these outcomes. Genetic inhibition of NNT recapitulated the effects of palmitate. PBMCs from obese (BMI >30) compared to lean subjects had lower NNT and glutathione expression, and higher Th17 cytokine expression, none of which were changed by exogenous palmitate. Our data identify NNT as a palmitate-regulated rheostat of redox balance that regulates immune cell function in obesity and suggest that dietary or therapeutic strategies aimed at increasing NNT expression may restore redox balance to ameliorate obesity-associated inflammation.
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Affiliation(s)
- Grace McCambridge
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA 01845, USA.
| | - Madhur Agrawal
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY 40506, USA.
| | - Alanna Keady
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA 01845, USA.
| | - Philip A Kern
- Department of Medicine, University of Kentucky, Lexington, KY 40506, USA.
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY 40506, USA.
| | | | - Barbara S Nikolajczyk
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY 40506, USA.
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY 40506, USA.
| | - Leena P Bharath
- Department of Nutrition and Public Health, Merrimack College, North Andover, MA 01845, USA.
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Long DE, Villasante Tezanos AG, Wise JN, Kern PA, Bamman MM, Peterson CA, Dennis RA. A guide for using NIH Image J for single slice cross-sectional area and composition analysis of the thigh from computed tomography. PLoS One 2019; 14:e0211629. [PMID: 30730923 PMCID: PMC6366874 DOI: 10.1371/journal.pone.0211629] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 01/17/2019] [Indexed: 12/25/2022] Open
Abstract
Reports using computed tomography (CT) to estimate thigh skeletal muscle cross-sectional area and mean muscle attenuation are often difficult to evaluate due to inconsistent methods of quantification and/or poorly described analysis methods. This CT tutorial provides step-by-step instructions in using free, NIH Image J software to quantify both muscle size and composition in the mid-thigh, which was validated against a robust commercially available software, SliceOmatic. CT scans of the mid-thigh were analyzed from 101 healthy individuals aged 65 and older. Mean cross-sectional area and mean attenuation values are presented across seven defined Hounsfield unit (HU) ranges along with the percent contribution of each region to the total mid-thigh area. Inter-software correlation coefficients ranged from R2 = 0.92–0.99 for all specific area comparisons measured using the Image J method compared to SliceOmatic. We recommend reporting individual HU ranges for all areas measured. Although HU range 0–100 includes the majority of skeletal muscle area, HU range -29 to 150 appears to be the most inclusive for quantifying total thigh muscle. Reporting all HU ranges is necessary to determine the relative contribution of each, as they may be differentially affected by age, obesity, disease, and exercise. This standardized operating procedure will facilitate consistency among investigators reporting computed tomography characteristics of the thigh on single slice images. Trial Registration: ClinicalTrials.gov NCT02308228.
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Affiliation(s)
- Douglas E. Long
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, KY, United States of America
- * E-mail:
| | | | - James N. Wise
- College of Medicine, Department of Radiology, University of Arkansas for Medical Sciences, Little Rock, AR, United States of America
| | - Philip A. Kern
- Department of Internal Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States of America
| | - Marcas M. Bamman
- Center for Exercise Medicine and Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Charlotte A. Peterson
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, KY, United States of America
| | - Richard A. Dennis
- Geriatric Research, Education and Clinical Center, Central Arkansas Veterans Healthcare System, North Little Rock, AR, United States of America
- Donald W Reynolds Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, AR, United States of America
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Walton RG, Kosmac K, Mula J, Fry CS, Peck BD, Groshong JS, Finlin BS, Zhu B, Kern PA, Peterson CA. Human skeletal muscle macrophages increase following cycle training and are associated with adaptations that may facilitate growth. Sci Rep 2019; 9:969. [PMID: 30700754 PMCID: PMC6353900 DOI: 10.1038/s41598-018-37187-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 11/23/2018] [Indexed: 12/26/2022] Open
Abstract
Skeletal muscle macrophages participate in repair and regeneration following injury. However, their role in physiological adaptations to exercise is unexplored. We determined whether endurance exercise training (EET) alters macrophage content and characteristics in response to resistance exercise (RE), and whether macrophages are associated with other exercise adaptations. Subjects provided vastus lateralis biopsies before and after one bout of RE, after 12 weeks of EET (cycling), and after a final bout of RE. M2 macrophages (CD11b+/CD206+) did not increase with RE, but increased in response to EET (P < 0.01). Increases in M2 macrophages were positively correlated with fiber hypertrophy (r = 0.49) and satellite cells (r = 0.47). M2c macrophages (CD206+/CD163+) also increased following EET (P < 0.001), and were associated with fiber hypertrophy (r = 0.64). Gene expression was quantified using NanoString. Following EET, the change in M2 macrophages was positively associated with changes in HGF, IGF1, and extracellular matrix genes. EET decreased expression of IL6 (P < 0.05), C/EBPβ (P < 0.01), and MuRF (P < 0.05), and increased expression of IL-4 (P < 0.01), TNFα (P < 0.01) and the TWEAK receptor FN14 (P < 0.05). The change in FN14 gene expression was inversely associated with changes in C/EBPβ (r = -0.58) and MuRF (r = -0.46) following EET. In cultured human myotubes, siRNA inhibition of FN14 increased expression of C/EBPβ (P < 0.05) and MuRF (P < 0.05). Our data suggest that macrophages contribute to the muscle response to EET, potentially including modulation of TWEAK-FN14 signaling.
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Affiliation(s)
- R Grace Walton
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.
| | - Kate Kosmac
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Jyothi Mula
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Christopher S Fry
- Deptartment of Nutrition & Metabolism, School of Health Professions, University of Texas Medical Branch at Galveston, Galveston, Texas, USA
| | - Bailey D Peck
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Jason S Groshong
- Department of Health Professions, University of Central Florida, Orlando, Florida, USA
| | - Brian S Finlin
- Department of Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Beibei Zhu
- Department of Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A Kern
- Department of Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Charlotte A Peterson
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
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Ravichandran S, Finlin BS, Kern PA, Özcan S. Sphk2 -/- mice are protected from obesity and insulin resistance. Biochim Biophys Acta Mol Basis Dis 2018; 1865:570-576. [PMID: 30593892 DOI: 10.1016/j.bbadis.2018.12.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/27/2018] [Accepted: 12/11/2018] [Indexed: 02/06/2023]
Abstract
Sphingosine kinases phosphorylate sphingosine to sphingosine 1‑phosphate (S1P), which functions as a signaling molecule. We have previously shown that sphingosine kinase 2 (Sphk2) is important for insulin secretion. To obtain a better understanding of the role of Sphk2 in glucose and lipid metabolism, we have characterized 20- and 52-week old Sphk2-/- mice using glucose and insulin tolerance tests and by analyzing metabolic gene expression in adipose tissue. A detailed metabolic characterization of these mice revealed that aging Sphk2-/- mice are protected from metabolic decline and obesity compared to WT mice. Specifically, we found that 52-week old male Sphk2-/- mice had decreased weight and fat mass, and increased glucose tolerance and insulin sensitivity compared to control mice. Indirect calorimetry studies demonstrated an increased energy expenditure and food intake in 52-week old male Sphk2-/- versus control mice. Furthermore, expression of adiponectin gene in adipose tissue was increased and the plasma levels of adiponectin elevated in aged Sphk2-/- mice compared to WT. Analysis of lipid metabolic gene expression in adipose tissue showed increased expression of the Atgl gene, which was associated with increased Atgl protein levels. Atgl encodes for the adipocyte triglyceride lipase, which catalyzes the rate-limiting step of lipolysis. In summary, these data suggest that mice lacking the Sphk2 gene are protected from obesity and insulin resistance during aging. The beneficial metabolic effects observed in aged Sphk2-/- mice may be in part due to enhanced lipolysis by Atgl and increased levels of adiponectin, which has lipid- and glucose-lowering effects.
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Affiliation(s)
- Shwetha Ravichandran
- Department of Molecular and Cellular Biochemistry, Barnstable Brown Diabetes and Obesity Center, College of Medicine, University of Kentucky, Lexington, KY, United States of America
| | - Brian S Finlin
- Department of Medicine, Division of Endocrinology, Barnstable Brown Diabetes and Obesity Center, College of Medicine, University of Kentucky, Lexington, KY, United States of America
| | - Philip A Kern
- Department of Medicine, Division of Endocrinology, Barnstable Brown Diabetes and Obesity Center, College of Medicine, University of Kentucky, Lexington, KY, United States of America
| | - Sabire Özcan
- Department of Molecular and Cellular Biochemistry, Barnstable Brown Diabetes and Obesity Center, College of Medicine, University of Kentucky, Lexington, KY, United States of America.
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Finlin BS, Memetimin H, Confides AL, Kasza I, Zhu B, Vekaria HJ, Harfmann B, Jones KA, Johnson ZR, Westgate PM, Alexander CM, Sullivan PG, Dupont-Versteegden EE, Kern PA. Human adipose beiging in response to cold and mirabegron. JCI Insight 2018; 3:121510. [PMID: 30089732 DOI: 10.1172/jci.insight.121510] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/03/2018] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The induction of beige adipocytes in s.c. white adipose tissue (WAT) depots of humans is postulated to improve glucose and lipid metabolism in obesity. The ability of obese, insulin-resistant humans to induce beige adipose tissue is unknown. METHODS We exposed lean and obese research participants to cold (30-minute ice pack application each day for 10 days of the upper thigh) or treated them with the β3 agonist mirabegron. We determined beige adipose marker expression by IHC and quantitative PCR, and we analyzed mitochondrial bioenergetics and UCP activity with an Oxytherm system. RESULTS Cold significantly induced UCP1 and TMEM26 protein in both lean and obese subjects, and this response was not associated with age. Interestingly, these proteins increased to the same extent in s.c. WAT of the noniced contralateral leg, indicating a crossover effect. We further analyzed the bioenergetics of purified mitochondria from the abdominal s.c. WAT of cold-treated subjects and determined that repeat ice application significantly increased uncoupled respiration, consistent with the UCP1 protein induction and subsequent activation. Cold also increased State 3 and maximal respiration, and this effect on mitochondrial bioenergetics was stronger in summer than winter. Chronic treatment (10 weeks; 50 mg/day) with the β3 receptor agonist mirabegron induces UCP1, TMEM26, CIDEA, and phosphorylation of HSL on serine660 in obese subjects. CONCLUSION Cold or β3 agonists cause the induction of beige adipose tissue in human s.c. WAT; this phenomenon may be exploited to increase beige adipose in older, insulin-resistant, obese individuals. TRIAL REGISTRATION Clinicaltrials.gov NCT02596776, NCT02919176. FUNDING NIH (DK107646, DK112282, P20GM103527, and by CTSA grant UL1TR001998).
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Affiliation(s)
- Brian S Finlin
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
| | - Hasiyet Memetimin
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
| | - Amy L Confides
- Department of Rehabilitation Sciences, College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Ildiko Kasza
- McArdle Laboratory for Cancer Research, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Beibei Zhu
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
| | - Hemendra J Vekaria
- Department of Neuroscience.,Spinal Cord and Brain Injury Research Center, and
| | - Brianna Harfmann
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
| | - Kelly A Jones
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
| | - Zachary R Johnson
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
| | - Philip M Westgate
- College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Caroline M Alexander
- McArdle Laboratory for Cancer Research, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Patrick G Sullivan
- Department of Neuroscience.,Spinal Cord and Brain Injury Research Center, and
| | - Esther E Dupont-Versteegden
- Department of Rehabilitation Sciences, College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A Kern
- The Department of Internal Medicine, Division of Endocrinology, and the Barnstable Brown Diabetes and Obesity Center, and
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Dennis RA, Villasante Tezanos AG, Landes RD, Wise JN, Padala KP, Kern PA, Garner KK, Padala PR, Bamman MM, Sullivan DH, Peterson CA, Long DE. Measuring Thigh Cross-sectional Areas From CT Scans. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000536490.55537.99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Thomas JM, Pendergast JS, Scott Black W, Kern PA, Clasey JL. Fat Mass, and Not Heart Rate Recovery is Associated With Cardiorespiratory Fitness in Young, Sedentary Adults. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000536264.04577.c4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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