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Ruiz-Otero N, Tessem JS, Banerjee RR. Pancreatic islet adaptation in pregnancy and postpartum. Trends Endocrinol Metab 2024:S1043-2760(24)00090-0. [PMID: 38697900 DOI: 10.1016/j.tem.2024.04.007] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 04/02/2024] [Accepted: 04/08/2024] [Indexed: 05/05/2024]
Abstract
Pancreatic islets, particularly insulin-producing β-cells, are central regulators of glucose homeostasis capable of responding to a variety of metabolic stressors. Pregnancy is a unique physiological stressor, necessitating the islets to adapt to the complex interplay of maternal and fetal-placental factors influencing the metabolic milieu. In this review we highlight studies defining gestational adaptation mechanisms within maternal islets and emerging studies revealing islet adaptations during the early postpartum and lactation periods. These include adaptations in both β and in 'non-β' islet cells. We also discuss insights into how gestational and postpartum adaptation may inform pregnancy-specific and general mechanisms of islet responses to metabolic stress and contribute to investigation of gestational diabetes.
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Affiliation(s)
- Nelmari Ruiz-Otero
- Division of Endocrinology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84601, USA
| | - Ronadip R Banerjee
- Division of Endocrinology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
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2
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Ellsworth PN, Herring JA, Leifer AH, Ray JD, Elison WS, Poulson PD, Crabtree JE, Van Ry PM, Tessem JS. CEBPA Overexpression Enhances β-Cell Proliferation and Survival. Biology (Basel) 2024; 13:110. [PMID: 38392328 PMCID: PMC10887016 DOI: 10.3390/biology13020110] [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: 12/30/2023] [Revised: 02/08/2024] [Accepted: 02/08/2024] [Indexed: 02/24/2024]
Abstract
A commonality between type 1 and type 2 diabetes is the decline in functional β-cell mass. The transcription factor Nkx6.1 regulates β-cell development and is integral for proper β-cell function. We have previously demonstrated that Nkx6.1 depends on c-Fos mediated upregulation and the nuclear hormone receptors Nr4a1 and Nr4a3 to increase β-cell insulin secretion, survival, and replication. Here, we demonstrate that Nkx6.1 overexpression results in upregulation of the bZip transcription factor CEBPA and that CEBPA expression is independent of c-Fos regulation. In turn, CEBPA overexpression is sufficient to enhance INS-1 832/13 β-cell and primary rat islet proliferation. CEBPA overexpression also increases the survival of β-cells treated with thapsigargin. We demonstrate that increased survival in response to ER stress corresponds with changes in expression of various genes involved in the unfolded protein response, including decreased Ire1a expression. These data show that CEBPA is sufficient to enhance functional β-cell mass by increasing β-cell proliferation and modulating the unfolded protein response.
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Affiliation(s)
- Peter N Ellsworth
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Jacob A Herring
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84602, USA
| | - Aaron H Leifer
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Jason D Ray
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Weston S Elison
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Peter Daniel Poulson
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Jacqueline E Crabtree
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Pam M Van Ry
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
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3
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Krueger ES, Griffin LE, Beales JL, Lloyd TS, Brown NJ, Elison WS, Kay CD, Neilson AP, Tessem JS. Bioavailable Microbial Metabolites of Flavanols Demonstrate Highly Individualized Bioactivity on In Vitro β-Cell Functions Critical for Metabolic Health. Metabolites 2023; 13:801. [PMID: 37512508 PMCID: PMC10385630 DOI: 10.3390/metabo13070801] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
Dietary flavanols are known for disease preventative properties but are often poorly absorbed. Gut microbiome flavanol metabolites are more bioavailable and may exert protective activities. Using metabolite mixtures extracted from the urine of rats supplemented with flavanols and treated with or without antibiotics, we investigated their effects on INS-1 832/13 β-cell glucose stimulated insulin secretion (GSIS) capacity. We measured insulin secretion under non-stimulatory (low) and stimulatory (high) glucose levels, insulin secretion fold induction, and total insulin content. We conducted treatment-level comparisons, individual-level dose responses, and a responder vs. non-responder predictive analysis of metabolite composition. While the first two analyses did not elucidate treatment effects, metabolites from 9 of the 28 animals demonstrated significant dose responses, regardless of treatment. Differentiation of responders vs. non-responder revealed that levels of native flavanols and valerolactones approached significance for predicting enhanced GSIS, regardless of treatment. Although treatment-level patterns were not discernable, we conclude that the high inter-individual variability shows that metabolite bioactivity on GSIS capacity is less related to flavanol supplementation or antibiotic treatment and may be more associated with the unique microbiome or metabolome of each animal. These findings suggest flavanol metabolite activities are individualized and point to the need for personalized nutrition practices.
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Affiliation(s)
- Emily S. Krueger
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (J.L.B.); (T.S.L.); (N.J.B.); (W.S.E.)
| | - Laura E. Griffin
- Plants for Human Health Institute, Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Kannapolis, NC 28081, USA; (L.E.G.); (C.D.K.); (A.P.N.)
| | - Joseph L. Beales
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (J.L.B.); (T.S.L.); (N.J.B.); (W.S.E.)
| | - Trevor S. Lloyd
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (J.L.B.); (T.S.L.); (N.J.B.); (W.S.E.)
| | - Nathan J. Brown
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (J.L.B.); (T.S.L.); (N.J.B.); (W.S.E.)
| | - Weston S. Elison
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (J.L.B.); (T.S.L.); (N.J.B.); (W.S.E.)
| | - Colin D. Kay
- Plants for Human Health Institute, Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Kannapolis, NC 28081, USA; (L.E.G.); (C.D.K.); (A.P.N.)
| | - Andrew P. Neilson
- Plants for Human Health Institute, Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Kannapolis, NC 28081, USA; (L.E.G.); (C.D.K.); (A.P.N.)
| | - Jeffery S. Tessem
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (J.L.B.); (T.S.L.); (N.J.B.); (W.S.E.)
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Racine KC, Iglesias-Carres L, Herring JA, Ferruzzi MG, Kay CD, Tessem JS, Neilson AP. Cocoa extract exerts sex-specific anti-diabetic effects in an aggressive type-2 diabetes model: A pilot study. Biochem Biophys Res Commun 2022; 626:205-210. [PMID: 35994831 DOI: 10.1016/j.bbrc.2022.08.018] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/05/2022] [Indexed: 11/27/2022]
Abstract
Type 2 diabetes (T2D) is characterized by hyperglycemia and insulin resistance. Cocoa may slow T2D development and progression. This study employed male and female BTBR.Cg-Lepob/ob/WiscJ (ob/ob) and wild type (WT) controls to assess the potential for cocoa to ameliorate progressive T2D and compare responses between sexes. Mice received diet without (WT, ob/ob) or with cocoa extract (ob/ob + c) for 10 weeks. Acute cocoa reduced fasting hyperglycemia in females, but not males, after 2 weeks. Chronic cocoa supplementation (6-10 weeks) ameliorated hyperinsulinemia in males and worsened hyperlipidemia and hyperinsulinemia in females, yet also preserved and enhanced beta cell survival in females. The underlying mechanisms of these differences warrant further study. If sex differences are apparent in subsequent preclinical studies, clinical studies will be warranted to establish whether these differences are relevant in humans. Sex differences may need to be considered when designing human dietary interventions for T2D.
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Affiliation(s)
- Kathryn C Racine
- Plants for Human Health Institute, North Carolina State University, 600 Laureate Way, Kannapolis, NC, 28081, USA.
| | - Lisard Iglesias-Carres
- Plants for Human Health Institute, North Carolina State University, 600 Laureate Way, Kannapolis, NC, 28081, USA.
| | - Jacob A Herring
- Department of Nutrition, Dietetics, & Food Science, Brigham Young University, S-243 ESC, Provo, UT, 84042, USA.
| | - Mario G Ferruzzi
- Plants for Human Health Institute, North Carolina State University, 600 Laureate Way, Kannapolis, NC, 28081, USA.
| | - Colin D Kay
- Plants for Human Health Institute, North Carolina State University, 600 Laureate Way, Kannapolis, NC, 28081, USA.
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics, & Food Science, Brigham Young University, S-243 ESC, Provo, UT, 84042, USA.
| | - Andrew P Neilson
- Plants for Human Health Institute, North Carolina State University, 600 Laureate Way, Kannapolis, NC, 28081, USA.
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Allen JG, Tessem JS. Ca 2+ Sensors Assemble: Function of the MCU Complex in the Pancreatic Beta Cell. Cells 2022; 11:cells11131993. [PMID: 35805078 PMCID: PMC9265474 DOI: 10.3390/cells11131993] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/17/2022] [Accepted: 06/20/2022] [Indexed: 12/05/2022] Open
Abstract
The Mitochondrial Calcium Uniporter Complex (MCU Complex) is essential for β-cell function due to its role in sustaining insulin secretion. The MCU complex regulates mitochondrial Ca2+ influx, which is necessary for increased ATP production following cellular glucose uptake, keeps the cell membrane K+ channels closed following initial insulin release, and ultimately results in sustained insulin granule exocytosis. Dysfunction in Ca2+ regulation results in an inability to sustain insulin secretion. This review defines the functions, structure, and mutations associated with the MCU complex members mitochondrial calcium uniporter protein (MCU), essential MCU regulator (EMRE), mitochondrial calcium uptake 1 (MICU1), mitochondrial calcium uptake 2 (MICU2), and mitochondrial calcium uptake 3 (MICU3) in the pancreatic β-cell. This review provides a framework for further evaluation of the MCU complex in β-cell function and insulin secretion.
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Wieland KL, Elison W, Tessem JS. Elevated Glucose Negatively Regulates Nkx6.1 Protein Level in the Pancreatic Beta Cell. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r5651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Jeffery S. Tessem
- Nutrition, Dietetics and Food ScienceBrigham Young UniversityProvoUT
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Iglesias-Carres L, Krueger ES, Herring JA, Tessem JS, Neilson AP. Potential of Phenolic Compounds and Their Gut Microbiota-Derived Metabolites to Reduce TMA Formation: Application of an In Vitro Fermentation High-Throughput Screening Model. J Agric Food Chem 2022; 70:3207-3218. [PMID: 35235743 DOI: 10.1021/acs.jafc.2c00247] [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] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Trimethylamine N-oxide (TMAO) is a pro-atherosclerotic product of dietary choline metabolism generated by a microbiome-host axis. The first step in this pathway is the enzymatic metabolism of choline to trimethylamine (TMA) by the gut microbiota. This reaction could be targeted to reduce atherosclerosis risk. We aimed to evaluate potential inhibitory effects of select dietary phenolics and their relevant gut microbial metabolites on TMA production via a human ex vivo-in vitro fermentation model. Various phenolics inhibited choline use and TMA production. The most bioactive compounds tested (caffeic acid, catechin, and epicatechin) reduced TMA-d9 formation (compared to control) by 57.5 ± 1.3 to 72.5 ± 0.4% at 8 h and preserved remaining choline-d9 concentrations by 194.1 ± 6.4 to 256.1 ± 6.3% at 8 h. These inhibitory effects were achieved without altering cell respiration or cell growth. However, inhibitory effects decreased at late fermentation times, which suggested that these compounds delay choline metabolism rather than completely inhibiting TMA formation. Overall, caffeic acid, catechin, and epicatechin were the most effective noncytotoxic inhibitors of choline use and TMA production. Thus, these compounds are proposed as lead bioactives to test in vivo.
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Affiliation(s)
- Lisard Iglesias-Carres
- Plants for Human Health Institute, Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Kannapolis, North Carolina 27695, United States
| | - Emily S Krueger
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah 84602, United States
| | - Jacob A Herring
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah 84602, United States
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah 84602, United States
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah 84602, United States
| | - Andrew P Neilson
- Plants for Human Health Institute, Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Kannapolis, North Carolina 27695, United States
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Imai Y, Soleimanpour SA, Tessem JS. Editorial: Study of pancreatic islets based on human models to understand pathogenesis of diabetes. Front Endocrinol (Lausanne) 2022; 13:1128653. [PMID: 36714557 PMCID: PMC9875287 DOI: 10.3389/fendo.2022.1128653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 12/27/2022] [Indexed: 01/11/2023] Open
Affiliation(s)
- Yumi Imai
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Iowa, Iowa City, IA, United States
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA, United States
- Endocrinology Section, Iowa City Veterans Affairs Medical Center, Iowa City, IA, United States
- *Correspondence: Yumi Imai,
| | - Scott A. Soleimanpour
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI, United States
| | - Jeffery S. Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT, United States
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Simonett SP, Shin S, Herring JA, Bacher R, Smith LA, Dong C, Rabaglia ME, Stapleton DS, Schueler KL, Choi J, Bernstein MN, Turkewitz DR, Perez-Cervantes C, Spaeth J, Stein R, Tessem JS, Kendziorski C, Keleş S, Moskowitz IP, Keller MP, Attie AD. Identification of direct transcriptional targets of NFATC2 that promote β cell proliferation. J Clin Invest 2021; 131:e144833. [PMID: 34491912 PMCID: PMC8553569 DOI: 10.1172/jci144833] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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: 10/02/2020] [Accepted: 09/02/2021] [Indexed: 12/13/2022] Open
Abstract
The transcription factor NFATC2 induces β cell proliferation in mouse and human islets. However, the genomic targets that mediate these effects have not been identified. We expressed active forms of Nfatc2 and Nfatc1 in human islets. By integrating changes in gene expression with genomic binding sites for NFATC2, we identified approximately 2200 transcriptional targets of NFATC2. Genes induced by NFATC2 were enriched for transcripts that regulate the cell cycle and for DNA motifs associated with the transcription factor FOXP. Islets from an endocrine-specific Foxp1, Foxp2, and Foxp4 triple-knockout mouse were less responsive to NFATC2-induced β cell proliferation, suggesting the FOXP family works to regulate β cell proliferation in concert with NFATC2. NFATC2 induced β cell proliferation in both mouse and human islets, whereas NFATC1 did so only in human islets. Exploiting this species difference, we identified approximately 250 direct transcriptional targets of NFAT in human islets. This gene set enriches for cell cycle-associated transcripts and includes Nr4a1. Deletion of Nr4a1 reduced the capacity of NFATC2 to induce β cell proliferation, suggesting that much of the effect of NFATC2 occurs through its induction of Nr4a1. Integration of noncoding RNA expression, chromatin accessibility, and NFATC2 binding sites enabled us to identify NFATC2-dependent enhancer loci that mediate β cell proliferation.
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Affiliation(s)
- Shane P. Simonett
- Biochemistry Department, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Sunyoung Shin
- Department of Mathematical Sciences, University of Texas at Dallas, Richardson, Texas, USA
| | - Jacob A. Herring
- Nutrition, Dietetics and Food Science Department, Brigham Young University, Provo, Utah, USA
| | - Rhonda Bacher
- Department of Biostatistics, University of Florida, Gainesville, Florida, USA
| | - Linsin A. Smith
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, Illinois, USA
| | - Chenyang Dong
- Department of Biostatistics and Medical Informatics, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Mary E. Rabaglia
- Biochemistry Department, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Donnie S. Stapleton
- Biochemistry Department, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Kathryn L. Schueler
- Biochemistry Department, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Jeea Choi
- Department of Biostatistics and Medical Informatics, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | | | - Daniel R. Turkewitz
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Carlos Perez-Cervantes
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, Illinois, USA
| | - Jason Spaeth
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Roland Stein
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Jeffery S. Tessem
- Nutrition, Dietetics and Food Science Department, Brigham Young University, Provo, Utah, USA
| | - Christina Kendziorski
- Department of Biostatistics and Medical Informatics, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Sündüz Keleş
- Department of Biostatistics and Medical Informatics, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Ivan P. Moskowitz
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, Illinois, USA
| | - Mark P. Keller
- Biochemistry Department, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Alan D. Attie
- Biochemistry Department, University of Wisconsin–Madison, Madison, Wisconsin, USA
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Aitken TJ, Crabtree JE, Jensen DM, Hess KH, Leininger BR, Tessem JS. Decreased proliferation of aged rat beta cells corresponds with enhanced expression of the cell cycle inhibitor p27 KIP1. Biol Cell 2021; 113:507-521. [PMID: 34523154 DOI: 10.1111/boc.202100035] [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] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/24/2021] [Accepted: 08/26/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND Over 400 million people are diabetic. Type 1 and type 2 diabetes are characterized by decreased functional β-cell mass and, consequently, decreased glucose-stimulated insulin secretion. A potential intervention is transplantation of β-cell containing islets from cadaveric donors. A major impediment to greater application of this treatment is the scarcity of transplant-ready β-cells. Therefore, inducing β-cell proliferation ex vivo could be used to expand functional β-cell mass prior to transplantation. Various molecular pathways are sufficient to induce proliferation of young β-cells; however, aged β-cells are refractory to these proliferative signals. Given that the majority of cadaveric donors fit an aged demographic, defining the mechanisms that impede aged β-cell proliferation is imperative. RESULTS We demonstrate that aged rat (5-month-old) β-cells are refractory to mitogenic stimuli that otherwise induce young rat (5-week-old) β-cell proliferation. We hypothesized that this change in proliferative capacity could be due to differences in cyclin-dependent kinase inhibitor expression. We measured levels of p16INK4a , p15INK4b , p18INK4c , p19INK4d , p21CIP1 , p27KIP1 and p57KIP2 by immunofluorescence analysis. Our data demonstrates an age-dependent increase of p27KIP1 in rat β-cells by immunofluorescence and was validated by increased p27KIP1 protein levels by western blot analysis. Interestingly, HDAC1, which modulates the p27KIP1 promoter acetylation state, is downregulated in aged rat islets. These data demonstrate increased p27KIP1 protein levels at 5 months of age, which may be due to decreased HDAC1 mediated repression of p27KIP1 expression. SIGNIFICANCE As the majority of transplant-ready β-cells come from aged donors, it is imperative that we understand why aged β-cells are refractory to mitogenic stimuli. Our findings demonstrate that increased p27KIP1 expression occurs early in β-cell aging, which corresponds with impaired β-cell proliferation. Furthermore, the correlation between HDAC1 and p27 levels suggests that pathways that activate HDAC1 in aged β-cells could be leveraged to decrease p27KIP1 levels and enhance β-cell proliferation.
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Affiliation(s)
- Talon J Aitken
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA.,Medical Education Program, Des Moines University, Des Moines, IA, 50312, USA
| | - Jacqueline E Crabtree
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA
| | - Daelin M Jensen
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA.,Biomedical Sciences, Ohio State University, Columbus, OH, 43210, USA
| | - Kavan H Hess
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA.,Medical Education Program, Idaho College of Osteopathic Medicine, Meridian, ID, 83642, USA
| | - Brennan R Leininger
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA.,Dental Education Program, UCLA School of Dentistry, Los Angeles, CA, 90024, USA
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA
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11
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Krueger ES, Lloyd TS, Tessem JS. The Accumulation and Molecular Effects of Trimethylamine N-Oxide on Metabolic Tissues: It's Not All Bad. Nutrients 2021; 13:nu13082873. [PMID: 34445033 PMCID: PMC8400152 DOI: 10.3390/nu13082873] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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: 07/23/2021] [Revised: 08/15/2021] [Accepted: 08/19/2021] [Indexed: 02/07/2023] Open
Abstract
Since elevated serum levels of trimethylamine N-oxide (TMAO) were first associated with increased risk of cardiovascular disease (CVD), TMAO research among chronic diseases has grown exponentially. We now know that serum TMAO accumulation begins with dietary choline metabolism across the microbiome-liver-kidney axis, which is typically dysregulated during pathogenesis. While CVD research links TMAO to atherosclerotic mechanisms in vascular tissue, its molecular effects on metabolic tissues are unclear. Here we report the current standing of TMAO research in metabolic disease contexts across relevant tissues including the liver, kidney, brain, adipose, and muscle. Since poor blood glucose management is a hallmark of metabolic diseases, we also explore the variable TMAO effects on insulin resistance and insulin production. Among metabolic tissues, hepatic TMAO research is the most common, whereas its effects on other tissues including the insulin producing pancreatic β-cells are largely unexplored. Studies on diseases including obesity, diabetes, liver diseases, chronic kidney disease, and cognitive diseases reveal that TMAO effects are unique under pathologic conditions compared to healthy controls. We conclude that molecular TMAO effects are highly context-dependent and call for further research to clarify the deleterious and beneficial molecular effects observed in metabolic disease research.
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Affiliation(s)
- Emily S. Krueger
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (T.S.L.)
| | - Trevor S. Lloyd
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (T.S.L.)
- Medical Education Program, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Jeffery S. Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA; (E.S.K.); (T.S.L.)
- Correspondence: ; Tel.: +1-801-422-9082
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12
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Griffin LE, Essenmacher L, Racine KC, Iglesias-Carres L, Tessem JS, Smith SM, Neilson AP. Diet-induced obesity in genetically diverse collaborative cross mouse founder strains reveals diverse phenotype response and amelioration by quercetin treatment in 129S1/SvImJ, PWK/EiJ, CAST/PhJ, and WSB/EiJ mice. J Nutr Biochem 2021; 87:108521. [PMID: 33039581 DOI: 10.1016/j.jnutbio.2020.108521] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 09/17/2020] [Accepted: 09/30/2020] [Indexed: 12/13/2022]
Abstract
Significant evidence suggests protective effects of flavonoids against obesity in animal models, but these often do not translate to humans. One explanation for this disconnect is use of a few mouse strains (notably C57BL/6 J) in obesity studies. Obesity is a multifactorial disease. The underlying causes are not fully replicated by the high-fat C57BL/6 J model, despite phenotypic similarities. Furthermore, the impact of genetic factors on the activities of flavonoids is unknown. This study was designed to explore how diverse mouse strains respond to diet-induced obesity when fed a representative flavonoid. A subset of Collaborative Cross founder strains (males and females) were placed on dietary treatments (low-fat, high-fat, high-fat with quercetin, high-fat with quercetin and antibiotics) longitudinally. Diverse responses were observed across strains and sexes. Quercetin appeared to moderately blunt weight gain in male C57 and both sexes of 129S1/SvImJ mice, and slightly increased weight gain in female C57 mice. Surprisingly, quercetin dramatically blunted weight gain in male, but not female, PWK/PhJ mice. For female mice, quercetin blunted weight gain (relative to the high-fat phase) in CAST/PhJ, PWK/EiJ and WSB/EiJ mice compared to C57. Antibiotics did not generally result in loss of protective effects of quercetin. This highlights complex interactions between genetic factors, sex, obesity stimuli, and flavonoid intake, and the need to move away from single inbred mouse models to enhance translatability to diverse humans. These data justify use of genetically diverse Collaborative Cross and Diversity Outbred models which are emerging as invaluable tools in the field of personalized nutrition.
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Affiliation(s)
- Laura E Griffin
- Department of Food, Bioprocessing and Nutrition Sciences, Plants for Human Health Institute, North Carolina State University, Kannapolis, North Carolina, USA
| | - Lauren Essenmacher
- Department of Food Science and Technology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
| | - Kathryn C Racine
- Department of Food, Bioprocessing and Nutrition Sciences, Plants for Human Health Institute, North Carolina State University, Kannapolis, North Carolina, USA
| | - Lisard Iglesias-Carres
- Department of Food, Bioprocessing and Nutrition Sciences, Plants for Human Health Institute, North Carolina State University, Kannapolis, North Carolina, USA
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah, USA
| | - Susan M Smith
- Department of Nutrition, Nutrition Research Institute, The University of North Carolina at Chapel Hill, Kannapolis, North Carolina, USA
| | - Andrew P Neilson
- Department of Food, Bioprocessing and Nutrition Sciences, Plants for Human Health Institute, North Carolina State University, Kannapolis, North Carolina, USA.
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13
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Chen T, Hill JT, Moore TM, Cheung ECK, Olsen ZE, Piorczynski TB, Marriott TD, Tessem JS, Walton CM, Bikman BT, Hansen JM, Thomson DM. Lack of skeletal muscle liver kinase B1 alters gene expression, mitochondrial content, inflammation and oxidative stress without affecting high-fat diet-induced obesity or insulin resistance. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165805. [PMID: 32339642 DOI: 10.1016/j.bbadis.2020.165805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 01/21/2020] [Revised: 04/02/2020] [Accepted: 04/16/2020] [Indexed: 12/28/2022]
Abstract
Ad libitum high-fat diet (HFD) induces obesity and skeletal muscle metabolic dysfunction. Liver kinase B1 (LKB1) regulates skeletal muscle metabolism by controlling the AMP-activated protein kinase family, but its importance in regulating muscle gene expression and glucose tolerance in obese mice has not been established. The purpose of this study was to determine how the lack of LKB1 in skeletal muscle (KO) affects gene expression and glucose tolerance in HFD-fed, obese mice. KO and littermate control wild-type (WT) mice were fed a standard diet or HFD for 14 weeks. RNA sequencing, and subsequent analysis were performed to assess mitochondrial content and respiration, inflammatory status, glucose and insulin tolerance, and muscle anabolic signaling. KO did not affect body weight gain on HFD, but heavily impacted mitochondria-, oxidative stress-, and inflammation-related gene expression. Accordingly, mitochondrial protein content and respiration were suppressed while inflammatory signaling and markers of oxidative stress were elevated in obese KO muscles. KO did not affect glucose or insulin tolerance. However, fasting serum insulin and skeletal muscle insulin signaling were higher in the KO mice. Furthermore, decreased muscle fiber size in skmLKB1-KO mice was associated with increased general protein ubiquitination and increased expression of several ubiquitin ligases, but not muscle ring finger 1 or atrogin-1. Taken together, these data suggest that the lack of LKB1 in skeletal muscle does not exacerbate obesity or insulin resistance in mice on a HFD, despite impaired mitochondrial content and function and elevated inflammatory signaling and oxidative stress.
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Affiliation(s)
- Ting Chen
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Jonathon T Hill
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Timothy M Moore
- David Geffen School of Medicine, Department of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Eric C K Cheung
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Zachary E Olsen
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Ted B Piorczynski
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Tanner D Marriott
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Chase M Walton
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Benjamin T Bikman
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Jason M Hansen
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - David M Thomson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA; Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602, USA.
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14
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Bitner BF, Ray JD, Kener KB, Herring JA, Tueller JA, Johnson DK, Tellez Freitas CM, Fausnacht DW, Allen ME, Thomson AH, Weber KS, McMillan RP, Hulver MW, Brown DA, Tessem JS, Neilson AP. Common gut microbial metabolites of dietary flavonoids exert potent protective activities in β-cells and skeletal muscle cells. J Nutr Biochem 2018; 62:95-107. [PMID: 30286378 DOI: 10.1016/j.jnutbio.2018.09.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [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: 05/18/2018] [Revised: 08/20/2018] [Accepted: 09/11/2018] [Indexed: 01/06/2023]
Abstract
Flavonoids are dietary compounds with potential anti-diabetes activities. Many flavonoids have poor bioavailability and thus low circulating concentrations. Unabsorbed flavonoids are metabolized by the gut microbiota to smaller metabolites, which are more bioavailable than their precursors. The activities of these metabolites may be partly responsible for associations between flavonoids and health. However, these activities remain poorly understood. We investigated bioactivities of flavonoid microbial metabolites [hippuric acid (HA), homovanillic acid (HVA), and 5-phenylvaleric acid (5PVA)] in primary skeletal muscle and β-cells compared to a native flavonoid [(-)-epicatechin, EC]. In muscle, EC was the most potent stimulator of glucose oxidation, while 5PVA and HA simulated glucose metabolism at 25 μM, and all compounds preserved mitochondrial function after insult. However, EC and the metabolites did not uncouple mitochonndrial respiration, with the exception of 5PVA at10 μM. In β-cells, all metabolites more potently enhanced glucose-stimulated insulin secretion (GSIS) compared to EC. Unlike EC, the metabolites appear to enhance GSIS without enhancing β-cell mitochondrial respiration or increasing expression of mitochondrial electron transport chain components, and with varying effects on β-cell insulin content. The present results demonstrate the activities of flavonoid microbial metabolites for preservation of β-cell function and glucose utilization. Additionally, our data suggest that metabolites and native compounds may act by distinct mechanisms, suggesting complementary and synergistic activities in vivo which warrant further investigation. This raises the intriguing prospect that bioavailability of native dietary flavonoids may not be as critical of a limiting factor to bioactivity as previously thought.
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Affiliation(s)
- Benjamin F Bitner
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, S243 ESC, Provo, UT 84602
| | - Jason D Ray
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, S243 ESC, Provo, UT 84602
| | - Kyle B Kener
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, S243 ESC, Provo, UT 84602
| | - Jacob A Herring
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, S243 ESC, Provo, UT 84602; Department of Microbiology and Molecular Biology, Brigham Young University, 3137 LSB, Provo, UT 84602
| | - Josie A Tueller
- Department of Microbiology and Molecular Biology, Brigham Young University, 3137 LSB, Provo, UT 84602
| | - Deborah K Johnson
- Department of Microbiology and Molecular Biology, Brigham Young University, 3137 LSB, Provo, UT 84602
| | - Claudia M Tellez Freitas
- Department of Microbiology and Molecular Biology, Brigham Young University, 3137 LSB, Provo, UT 84602
| | - Dane W Fausnacht
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060
| | - Mitchell E Allen
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060
| | - Alexander H Thomson
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060
| | - K Scott Weber
- Department of Microbiology and Molecular Biology, Brigham Young University, 3137 LSB, Provo, UT 84602
| | - Ryan P McMillan
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060; Metabolic Phenotyping Core Facility, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060
| | - Matthew W Hulver
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060; Metabolic Phenotyping Core Facility, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060
| | - David A Brown
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060; Metabolic Phenotyping Core Facility, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060; Virginia Tech Center for Drug Discovery, 800 West Campus Dr. Room 3111, Blacksburg, VA 24061
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, S243 ESC, Provo, UT 84602
| | - Andrew P Neilson
- Department of Food Science and Technology, Virginia Tech, 1981 Kraft Dr., Blacksburg, VA 24060.
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15
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Parker BA, Walton CM, Carr ST, Andrus JL, Cheung ECK, Duplisea MJ, Wilson EK, Draney C, Lathen DR, Kenner KB, Thomson DM, Tessem JS, Bikman BT. β-Hydroxybutyrate Elicits Favorable Mitochondrial Changes in Skeletal Muscle. Int J Mol Sci 2018; 19:E2247. [PMID: 30071599 PMCID: PMC6121962 DOI: 10.3390/ijms19082247] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [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] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 07/26/2018] [Accepted: 07/27/2018] [Indexed: 01/01/2023] Open
Abstract
The clinical benefit of ketosis has historically and almost exclusively centered on neurological conditions, lending insight into how ketones alter mitochondrial function in neurons. However, there is a gap in our understanding of how ketones influence mitochondria within skeletal muscle cells. The purpose of this study was to elucidate the specific effects of β-hydroxybutyrate (β-HB) on muscle cell mitochondrial physiology. In addition to increased cell viability, murine myotubes displayed beneficial mitochondrial changes evident in reduced H₂O₂ emission and less mitochondrial fission, which may be a result of a β-HB-induced reduction in ceramides. Furthermore, muscle from rats in sustained ketosis similarly produced less H₂O₂ despite an increase in mitochondrial respiration and no apparent change in mitochondrial quantity. In sum, these results indicate a general improvement in muscle cell mitochondrial function when β-HB is provided as a fuel.
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Affiliation(s)
- Brian A Parker
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Chase M Walton
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Sheryl T Carr
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Jacob L Andrus
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Eric C K Cheung
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Michael J Duplisea
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Esther K Wilson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Carrie Draney
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84604, USA.
| | - Daniel R Lathen
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84604, USA.
| | - Kyle B Kenner
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84604, USA.
| | - David M Thomson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Jeffery S Tessem
- Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84604, USA.
| | - Benjamin T Bikman
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84604, USA.
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16
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Kener KB, Munk DJ, Hancock CR, Tessem JS. High-resolution Respirometry to Measure Mitochondrial Function of Intact Beta Cells in the Presence of Natural Compounds. J Vis Exp 2018. [PMID: 29443067 DOI: 10.3791/57053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
High-resolution respirometry allows for the measurement of oxygen consumption of isolated mitochondria, cells and tissues. Beta cells play a critical role in the body by controlling blood glucose levels through insulin secretion in response to elevated glucose concentrations. Insulin secretion is controlled by glucose metabolism and mitochondrial respiration. Therefore, measuring intact beta cell respiration is essential to be able to improve beta cell function as a treatment for diabetes. Using intact 832/13 INS-1 derived beta cells we can measure the effect of increasing glucose concentration on cellular respiration. This protocol allows us to measure beta cell respiration in the presence or absence of various compounds, allowing one to determine the effect of given compounds on intact cell respiration. Here we demonstrate the effect of two naturally occurring compounds, monomeric epicatechin and curcumin, on beta cell respiration under the presence of low (2.5 mM) or high glucose (16.7 mM) conditions. This technique can be used to determine the effect of various compounds on intact beta cell respiration in the presence of differing glucose concentrations.
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Affiliation(s)
- Kyle B Kener
- Nutrition, Dietetics and Food Science Department, Brigham Young University
| | - Devin J Munk
- Nutrition, Dietetics and Food Science Department, Brigham Young University
| | - Chad R Hancock
- Nutrition, Dietetics and Food Science Department, Brigham Young University
| | - Jeffery S Tessem
- Nutrition, Dietetics and Food Science Department, Brigham Young University;
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17
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Sampson M, Lathen DR, Dallon BW, Draney C, Ray JD, Kener KB, Parker BA, Gibbs JL, Gropp JS, Tessem JS, Bikman BT. β-Hydroxybutyrate improves β-cell mitochondrial function and survival. J insul resist 2017. [DOI: 10.4102/jir.v2i1.25] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Pharmacological interventions aimed at improving outcomes in type 2 diabetes and achieving normoglycaemia, including insulin therapy, are increasingly common, despite the potential for substantial side effects. Carbohydrate-restricted diets that result in increased ketogenesis have effectively been used to improve insulin resistance, a fundamental feature of type 2 diabetes. In addition, limited evidence suggests that states of ketogenesis may also improve β-cell function in type 2 diabetics. Considering how little is known regarding the effects of ketones on β-cell function, we sought to determine the specific effects of β-Hydroxybutyrate (βHB) on pancreatic β-cell physiology and mitochondrial function. βHB treatment increased β-cell survival and proliferation, while also increasing mitochondrial mass, respiration and adenosine triphosphate (ATP) production. Despite these improvements, were unable to detect an increase in β-cell or islet insulin production and secretion. Collectively, these findings have two implications. Firstly, they indicate that β-cells have improved survival and proliferation in the midst of βHB, the circulating form of ketones. Secondly, insulin secretion does not appear to be directly related to apparent improvements in mitochondrial function and cellular proliferation.
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18
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Reynolds MS, Hancock CR, Ray JD, Kener KB, Draney C, Garland K, Hardman J, Bikman BT, Tessem JS. β-Cell deletion of Nr4a1 and Nr4a3 nuclear receptors impedes mitochondrial respiration and insulin secretion. Am J Physiol Endocrinol Metab 2016; 311:E186-201. [PMID: 27221116 DOI: 10.1152/ajpendo.00022.2016] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/17/2016] [Indexed: 01/09/2023]
Abstract
β-Cell insulin secretion is dependent on proper mitochondrial function. Various studies have clearly shown that the Nr4a family of orphan nuclear receptors is essential for fuel utilization and mitochondrial function in liver, muscle, and adipose. Previously, we have demonstrated that overexpression of Nr4a1 or Nr4a3 is sufficient to induce proliferation of pancreatic β-cells. In this study, we examined whether Nr4a expression impacts pancreatic β-cell mitochondrial function. Here, we show that β-cell mitochondrial respiration is dependent on the nuclear receptors Nr4a1 and Nr4a3. Mitochondrial respiration in permeabilized cells was significantly decreased in β-cells lacking Nr4a1 or Nr4a3. Furthermore, respiration rates of intact cells deficient for Nr4a1 or Nr4a3 in the presence of 16 mM glucose resulted in decreased glucose mediated oxygen consumption. Consistent with this reduction in respiration, a significant decrease in glucose-stimulated insulin secretion rates is observed with deletion of Nr4a1 or Nr4a3. Interestingly, the changes in respiration and insulin secretion occur without a reduction in mitochondrial content, suggesting decreased mitochondrial function. We establish that knockdown of Nr4a1 and Nr4a3 results in decreased expression of the mitochondrial dehydrogenase subunits Idh3g and Sdhb. We demonstrate that loss of Nr4a1 and Nr4a3 impedes production of ATP and ultimately inhibits glucose-stimulated insulin secretion. These data demonstrate for the first time that the orphan nuclear receptors Nr4a1 and Nr4a3 are critical for β-cell mitochondrial function and insulin secretion.
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Affiliation(s)
- Merrick S Reynolds
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Chad R Hancock
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Jason D Ray
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Kyle B Kener
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Carrie Draney
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Kevin Garland
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Jeremy Hardman
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
| | - Benjamin T Bikman
- Physiology and Developmental Biology Department, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Jeffery S Tessem
- Nutrition, Dietetics, and Food Science Department, College of Life Sciences, Brigham Young University, Provo, Utah; and
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19
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Ray JD, Kener KB, Bitner BF, Wright BJ, Ballard MS, Barrett EJ, Hill JT, Moss LG, Tessem JS. Nkx6.1-mediated insulin secretion and β-cell proliferation is dependent on upregulation of c-Fos. FEBS Lett 2016; 590:1791-803. [PMID: 27164028 DOI: 10.1002/1873-3468.12208] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [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: 01/12/2016] [Revised: 04/02/2016] [Accepted: 05/05/2016] [Indexed: 01/01/2023]
Abstract
Understanding the molecular pathways that enhance β-cell proliferation, survival, and insulin secretion may be useful to improve treatments for diabetes. Nkx6.1 induces proliferation through the Nr4a nuclear receptors, and improves insulin secretion and survival through the peptide hormone VGF. Here we demonstrate that Nkx6.1-mediated upregulation of Nr4a1, Nr4a3, and VGF is dependent on c-Fos expression. c-Fos overexpression results in activation of Nkx6.1 responsive genes and increases β-cell proliferation, insulin secretion, and cellular survival. c-Fos knockdown impedes Nkx6.1-mediated β-cell proliferation and insulin secretion. These data demonstrate that c-Fos is critical for Nkx6.1-mediated expansion of functional β-cell mass.
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Affiliation(s)
- Jason D Ray
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Kyle B Kener
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Benjamin F Bitner
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Brent J Wright
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Matthew S Ballard
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Emily J Barrett
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Jonathon T Hill
- Physiology and Developmental Biology Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
| | - Larry G Moss
- Sarah W. Stedman Nutrition and Metabolism Center and Duke Molecular Physiology Institute, Departments of Pharmacology and Cancer Biology and Medicine, Duke University, Durham, NC, USA
| | - Jeffery S Tessem
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT, USA
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20
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Draney C, Hobson AE, Grover SG, Jack BO, Tessem JS. Cdk5r1 Overexpression Induces Primary β-Cell Proliferation. J Diabetes Res 2016; 2016:6375804. [PMID: 26788519 PMCID: PMC4691621 DOI: 10.1155/2016/6375804] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 08/15/2015] [Accepted: 08/18/2015] [Indexed: 02/07/2023] Open
Abstract
Decreased β-cell mass is a hallmark of type 1 and type 2 diabetes. Islet transplantation as a method of diabetes therapy is hampered by the paucity of transplant ready islets. Understanding the pathways controlling islet proliferation may be used to increase functional β-cell mass through transplantation or by enhanced growth of endogenous β-cells. We have shown that the transcription factor Nkx6.1 induces β-cell proliferation by upregulating the orphan nuclear hormone receptors Nr4a1 and Nr4a3. Using expression analysis to define Nkx6.1-independent mechanisms by which Nr4a1 and Nr4a3 induce β-cell proliferation, we demonstrated that cyclin-dependent kinase 5 regulatory subunit 1 (Cdk5r1) is upregulated by Nr4a1 and Nr4a3 but not by Nkx6.1. Overexpression of Cdk5r1 is sufficient to induce primary rat β-cell proliferation while maintaining glucose stimulated insulin secretion. Overexpression of Cdk5r1 in β-cells confers protection against apoptosis induced by etoposide and thapsigargin, but not camptothecin. The Cdk5 kinase complex inhibitor roscovitine blocks islet proliferation, suggesting that Cdk5r1 mediated β-cell proliferation is a kinase dependent event. Overexpression of Cdk5r1 results in pRb phosphorylation, which is inhibited by roscovitine treatment. These data demonstrate that activation of the Cdk5 kinase complex is sufficient to induce β-cell proliferation while maintaining glucose stimulated insulin secretion.
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Affiliation(s)
- Carrie Draney
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Amanda E. Hobson
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Samuel G. Grover
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Benjamin O. Jack
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Jeffery S. Tessem
- Nutrition, Dietetics and Food Science Department, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA
- *Jeffery S. Tessem:
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21
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Abstract
Type 1 and type 2 diabetes are ultimately characterized by depleted β-cell mass. Characterization of the molecular pathways that control β-cell proliferation could be harnessed to restore these cells. The homeobox β-cell transcription factor Nkx6.1 induces β-cell proliferation by activating the orphan nuclear receptors Nr4a1 and Nr4a3. Here, we demonstrate that Nkx6.1 localizes to the promoter of the mitotic kinase AURKA (Aurora Kinase A) and induces its expression. Adenovirus mediated overexpression of AURKA is sufficient to induce proliferation in primary rat islets while maintaining glucose stimulated insulin secretion. Furthermore, AURKA is necessary for Nkx6.1 mediated β-cell proliferation as demonstrated by shRNA mediated knock down and pharmacological inhibition of AURKA kinase activity. AURKA preferentially induces DNA replication in β-cells as measured by BrdU incorporation, and enhances the rate of histone H3 phosphorylation in primary β-cells, demonstrating that AURKA induces the replicative and mitotic cell cycle phases in rat β-cells. Finally, overexpression of AURKA results in phosphorylation of the cell cycle regulator p53, which targets p53 for degradation and permits cell cycle progression. These studies define a pathway by which AURKA upregulation by Nkx6.1 results in phosphorylation and degradation of p53, thus removing a key inhibitory factor and permitting engagement of the β-cell proliferation pathway.
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Key Words
- AURKA
- AURKA, Aurora Kinase A
- BrdU, bromodeoxyuridine
- ChIP, chromatin immunoprecipitation
- Nkx6.1
- Nkx6.1, NK Homeobox 1
- Nr4a1, Nuclear receptor subfamily 4, group A, member 1
- Nr4a3, Nuclear receptor subfamily 4, group A, member 3
- cell cycle
- islet
- p53
- proliferation
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Affiliation(s)
- Amanda Hobson
- Nutrition; Dietetics and Food Science Department; College of Life Sciences; Brigham Young University, Provo, Utah USA
| | - Carrie Draney
- Nutrition; Dietetics and Food Science Department; College of Life Sciences; Brigham Young University, Provo, Utah USA
| | - Andrew Stratford
- Nutrition; Dietetics and Food Science Department; College of Life Sciences; Brigham Young University, Provo, Utah USA
| | - Thomas C Becker
- Duke Molecular Physiology Institute; Duke University Medical Center; Durham, NC USA
| | - Danhong Lu
- Duke Molecular Physiology Institute; Duke University Medical Center; Durham, NC USA
| | - Michelle Arlotto
- Duke Molecular Physiology Institute; Duke University Medical Center; Durham, NC USA
| | - Jeffery S Tessem
- Nutrition; Dietetics and Food Science Department; College of Life Sciences; Brigham Young University, Provo, Utah USA
- Correspondence to: Jeffery Sivert Tessem;
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Tessem JS, Jensen JN, Pelli H, Dai XM, Zong XH, Stanley ER, Jensen J, DeGregori J. Critical roles for macrophages in islet angiogenesis and maintenance during pancreatic degeneration. Diabetes 2008; 57:1605-17. [PMID: 18375440 PMCID: PMC2575065 DOI: 10.2337/db07-1577] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Chronic pancreatitis, characterized by pancreatic exocrine tissue destruction with initial maintenance of islets, eventually leads to insulin-dependent diabetes in most patients. Mice deficient for the transcription factors E2F1 and E2F2 suffer from a chronic pancreatitis-like syndrome and become diabetic. Surprisingly, onset of diabetes can be prevented through bone marrow transplantation. The goal of the described studies was to determine the hematopoietic cell type responsible for maintaining islets and the associated mechanism of this protection. RESEARCH DESIGN AND METHODS Mouse models of acute and chronic pancreatitis, together with mice genetically deficient for macrophage production, were used to determine roles for macrophages in islet angiogenesis and maintenance. RESULTS We demonstrate that macrophages are essential for preventing endocrine cell loss and diabetes. Macrophages expressing matrix metalloproteinase-9 migrate to the deteriorating pancreas. E2f1/E2f2 mutant mice transplanted with wild-type, but not macrophage-deficient colony stimulating factor 1 receptor mutant (Csf1r(-/-)), bone marrow exhibit increased angiogenesis and proliferation within islets, coinciding with increased islet mass. A similar macrophage dependency for islet and islet vasculature maintenance is observed during caerulein-induced pancreatitis. CONCLUSIONS These findings demonstrate that macrophages promote islet angiogenesis and protect against islet loss during exocrine degeneration, could explain why most patients with chronic pancreatitis develop diabetes, and suggest an avenue for preventing pancreatitis-associated diabetes.
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Affiliation(s)
- Jeffery S. Tessem
- Department of Biochemistry and Molecular Genetics, Program in Molecular Biology, Integrated Department of Immunology, University of Colorado Denver School of Medicine, Aurora, CO 80045
| | - Jan N. Jensen
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver School of Medicine, 1775 N. Ursula St., Room 4306D, P.O. Box 6511, Aurora, CO 80045-6511
| | - Hanna Pelli
- Department of Biochemistry and Molecular Genetics, Program in Molecular Biology, Integrated Department of Immunology, University of Colorado Denver School of Medicine, Aurora, CO 80045
| | - Xu-Ming Dai
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, N.Y., U.S.A., 10461
| | - Xiao-Hua Zong
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, N.Y., U.S.A., 10461
| | - E. Richard Stanley
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, N.Y., U.S.A., 10461
| | - Jan Jensen
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver School of Medicine, 1775 N. Ursula St., Room 4306D, P.O. Box 6511, Aurora, CO 80045-6511
| | - James DeGregori
- Department of Biochemistry and Molecular Genetics, Program in Molecular Biology, Integrated Department of Immunology, University of Colorado Denver School of Medicine, Aurora, CO 80045
- Corresponding author: James DeGregori; phone: 303-724-3230; fax: 303-724-3215, E-mail:
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Abstract
With more than 177 million people suffering from diabetes worldwide, and the number expected to double by 2030, finding new ways to treat this disease is a high priority. Intensive effort is being directed towards developing mechanisms for increasing beta-cell expansion as a diabetic therapeutic. Recent studies, in which adult bone marrow has been used to induce beta-cell expansion in mice, have shown both exciting and controversial results. In these reports, marrow-derived cells can contribute towards beta-cell maintenance both by promoting endogenous beta-cell expansion and possibly by transdifferentiation into beta-cells. These studies reveal mechanisms for potential therapeutic intervention.
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Affiliation(s)
- Jeffery S Tessem
- Department of Biochemistry and Molecular Genetics, University of Colorado Health Sciences Center at Fitzsimons, PO Box 6511, MS8101 Aurora, CO 80045, USA
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24
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Li FX, Zhu JW, Tessem JS, Beilke J, Varella-Garcia M, Jensen J, Hogan CJ, DeGregori J. The development of diabetes in E2f1/E2f2 mutant mice reveals important roles for bone marrow-derived cells in preventing islet cell loss. Proc Natl Acad Sci U S A 2003; 100:12935-40. [PMID: 14566047 PMCID: PMC240722 DOI: 10.1073/pnas.2231861100] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Our studies of mice deficient for the E2F1 and E2F2 transcription factors have revealed essential roles for these proteins in the cell cycle control of pancreatic exocrine cells and the regulation of pancreatic beta cell maintenance. Pancreatic exocrine cells in E2f1-/-E2f2 mutant mice become increasingly polyploid with age, coinciding with severe exocrine atrophy. Furthermore, mice deficient for both E2F1 and E2F2 develop nonautoimmune, insulin-dependent diabetes with high penetrance. Surprisingly, transplantation of wild-type bone marrow can prevent or rescue diabetes in E2f1-/-E2f2-/-mice. We hypothesize that exocrine degeneration results in a destructive environment for beta cells, which can be alleviated by restoration of the hematopoietic system that is also defective in E2f1-/-E2f2-/-mice The demonstration that beta cell maintenance under conditions of stress is influenced by bone marrow-derived cells may provide important insight into the design of therapies to boost islet mass and function in diabetic patients.
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Affiliation(s)
- Feng X. Li
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - Jing W. Zhu
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - Jeffery S. Tessem
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - Joshua Beilke
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - Marileila Varella-Garcia
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - Jan Jensen
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - Christopher J. Hogan
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
| | - James DeGregori
- Departments of Biochemistry and Molecular Genetics,Medicine/Medical Oncology, and Pediatrics,Integrated Department of Immunology, Program in Molecular Biology, and Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262
- To whom correspondence should be addressed. E-mail:
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