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Lin WL, Chien MM, Patchara S, Wang W, Faradina A, Huang SY, Tung TH, Tsai CS, Skalny AV, Tinkov AA, Chang CC, Chang JS. Essential trace element and phosphatidylcholine remodeling: Implications for body composition and insulin resistance. J Trace Elem Med Biol 2024; 85:127479. [PMID: 38878466 DOI: 10.1016/j.jtemb.2024.127479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/29/2024] [Accepted: 05/29/2024] [Indexed: 07/30/2024]
Abstract
BACKGROUND Recent studies indicated that bioactive lipids of phosphatidylcholines (PCs) and lysophosphatidylcholines (LysoPCs) predict unhealthy metabolic phenotypes, but results remain inconsistent. To fill this knowledge gap, we investigated whether essential trace elements affect PC-Lyso PC remodeling pathways and the risk of insulin resistance (IR). METHODS Anthropometric and blood biochemical data (glucose, insulin, and lipoprotein-associated phospholipase A2 (Lp-PLA2)) were obtained from 99 adults. Blood essential/probably essential trace elements and lipid metabolites were respectively measured by inductively coupled plasma mass spectrometry (ICP-MS), and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). RESULT AND CONCLUSION Except for LysoPC (O-18:0/0:0), an inverse V shape was observed between body weight and PC and LysoPC species. A Pearson correlation analysis showed that essential/probably-essential metals (Se, Cu, and Ni: r=-0.4∼-0.7) were negatively correlated with PC metabolites but positively correlated with LysoPC (O-18:0/0:0) (Se, Cu, and Ni: r=0.85-0.64). Quantile-g computation showed that one quantile increase in essential metals was associated with a 2.16-fold increase in serum Lp-PLA2 (β=2.16 (95 % confidence interval (CI): 0.34, 3.98), p=0.023), which are key enzymes involved in PC/Lyso PC metabolism. An interactive analysis showed that compared to those with the lowest levels (reference), individuals with the highest levels of serum PCs (pooled, M2) and the lowest essential/probably essential metals (M1) were associated with a healthier body composition and had a 76 % decreased risk of IR (odds ratio (OR)=0.24 (95 % CI: 0.06, 0.90), p<0.05). In contrast, increased exposure to LysoPC(O-18:0/0:0) (M2) and essential metals (M2) exhibited an 8.22-times highest risk of IR (OR= 8.22 (2.07, 32.57), p<0.05) as well as an altered body composition. In conclusion, overexposure to essential/probably essential trace elements may promote an unhealthy body weight and IR through modulating PC/LysoPC remodeling pathways.
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Affiliation(s)
- Wen-Ling Lin
- School of Nutrition and Health Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan, ROC
| | - Mu-Ming Chien
- Department of Pediatrics, Taipei Medical University Hospital, Taipei 11031, Taiwan, ROC
| | - Sangopas Patchara
- School of Nutrition and Health Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan, ROC
| | - Weu Wang
- Division of Digestive Surgery, Department of Surgery, Taipei Medical University Hospital, Taipei 11301, Taiwan, ROC; Department of Surgery, College of Medicine, Taipei Medical University, Taipei 11301, Taiwan, ROC
| | - Amelia Faradina
- School of Nutrition and Health Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan, ROC
| | - Shih-Yi Huang
- School of Nutrition and Health Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan, ROC; Center for Reproductive Medicine & Sciences, Taipei Medical University Hospital, Taipei 11031, Taiwan, ROC; Graduate Institute of Metabolism and Obesity Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan, ROC
| | - Te-Hsuan Tung
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Chien-Sung Tsai
- Division of Cardiovascular Surgery, Tri-service General Hospital, National Defense Medical Center, Taipei 114202, Taiwan, ROC; Department and Graduate Institute of Pharmacology, National Defense Medical Center, Taipei 114202, Taiwan, ROC
| | - Anatoly V Skalny
- Center of Bioelementology and Human Ecology, IM Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia; Department of Medical Elementology, Peoples' Friendship University of Russia (RUDN University), Moscow 117198, Russia
| | - Alexey A Tinkov
- Center of Bioelementology and Human Ecology, IM Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia; Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, Yaroslavl, Russia
| | - Chun-Chao Chang
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Taipei Medical University Hospital, Taiwan, ROC; Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Medicine, Collage of Medicine, Taipei Medical University, Taipei 11031, Taiwan, ROC
| | - Jung-Su Chang
- School of Nutrition and Health Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan, ROC; Nutrition Research Center, Taipei Medical University Hospital, Taipei 11031, Taiwan, ROC; Chinese Taipei Society for the Study of Obesity (CTSSO), Taipei 11031, Taiwan, ROC; TMU Research Center for Digestive Medicine, Taipei Medical University, Taipei 11031, Taiwan, ROC.
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Prabutzki P, Schiller J, Engel KM. Phospholipid-derived lysophospholipids in (patho)physiology. Atherosclerosis 2024:118569. [PMID: 39227208 DOI: 10.1016/j.atherosclerosis.2024.118569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/17/2024] [Accepted: 08/21/2024] [Indexed: 09/05/2024]
Abstract
Phospholipids (PL) are major components of cellular membranes and changes in PL metabolism have been associated with the pathogenesis of numerous diseases. Lysophosphatidylcholine (LPC) in particular, is a comparably abundant component of oxidatively damaged tissues. LPC originates from the cleavage of phosphatidylcholine (PC) by phospholipase A2 or the reaction of lipids with reactive oxygen species (ROS) such as HOCl. Another explanation of increased LPC concentration is the decreased re-acylation of LPC into PC. While there are also several other lysophospholipids, LPC is the most abundant lysophospholipid in mammals and will therefore be the focus of this review. LPC is involved in many physiological processes. It induces the migration of lymphocytes, fostering the production of pro-inflammatory compounds by inducing oxidative stress. LPC also "signals" via G protein-coupled and Toll-like receptors and has been implicated in the development of different diseases. However, LPCs are not purely "bad": this is reflected by the fact that the concentration and fatty acyl composition of LPC varies under different conditions, in plasma of healthy and diseased individuals, in tissues and different tumors. Targeting LPC and lipid metabolism and restoring homeostasis might be a potential therapeutic method for inflammation-related diseases.
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Affiliation(s)
- Patricia Prabutzki
- Institute of Medical Physics and Biophysics, Faculty of Medicine, Leipzig University, Härtelstr. 16-18, D 04107 Leipzig, Germany
| | - Jürgen Schiller
- Institute of Medical Physics and Biophysics, Faculty of Medicine, Leipzig University, Härtelstr. 16-18, D 04107 Leipzig, Germany
| | - Kathrin M Engel
- Institute of Medical Physics and Biophysics, Faculty of Medicine, Leipzig University, Härtelstr. 16-18, D 04107 Leipzig, Germany.
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3
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Zhang Z, Liu Y, Lv J, Zhang D, Hu K, Li J, Ma J, Cui L, Zhao H. Differential Lipidomic Characteristics of Children Born to Women with Polycystic Ovary Syndrome. Front Endocrinol (Lausanne) 2021; 12:698734. [PMID: 34434168 PMCID: PMC8380809 DOI: 10.3389/fendo.2021.698734] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To describe the lipidomic characteristics of offspring born to polycystic ovary syndrome (PCOS) women (PCOS-off) and assess the associations between differential lipids and clinical phenotypes. METHODS Ultra performance liquid chromatography and mass spectrometry were performed on plasma samples from 70 PCOS-off and 71 healthy controls. The associations of differential metabolites with clinical phenotypes were examined by multiple linear regression. RESULTS Forty-four metabolites were significantly altered in PCOS-off, including 8 increased and 36 decreased. After stratification according to sex, 44 metabolites (13 increased and 31 decreased) were expressed differently in girls born to PCOS women (PCOS-g), most of which were glycerolipids. Furthermore, 46 metabolites (9 increased and 35 decreased) were expressed differently in boys born to PCOS women (PCOS-b), most of which were glycerophospholipids. Significant associations of metabolites with weight Z-score and high density lipoprotein cholesterol were found in PCOS-off. Triglycerides, low density lipoprotein cholesterol, and thyroid-stimulating hormone were separately correlated with some lipids in PCOS-g and PCOS-b. CONCLUSIONS PCOS-off showed specific lipid profile alterations. The abnormal level of glycerophospholipids and sphingomyelin indicated the risk of glucose metabolism and cardiovascular diseases in PCOS-off. Some lipids, such as phosphatidylcholines, lysophosphatidylcholine and sphingomyelin, may be the potential markers. The results broadened our understanding of PCOS-offs' cardiometabolic status and emphasized more specific and detailed monitoring and management in this population.
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Affiliation(s)
- Zhirong Zhang
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
| | - Yue Liu
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
| | - Jiali Lv
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Di Zhang
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
| | - Kuona Hu
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
| | - Jingyu Li
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
| | - Jinlong Ma
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
| | - Linlin Cui
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
- *Correspondence: Linlin Cui,
| | - Han Zhao
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong University, Jinan, China
- Shandong Provincial Clinical Research Center for Reproductive Health, Shandong University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, China
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Kim S, Subramanian V, Abdel-Latif A, Lee S. Role of Heparin-Binding Epidermal Growth Factor-Like Growth Factor in Oxidative Stress-Associated Metabolic Diseases. Metab Syndr Relat Disord 2020; 18:186-196. [PMID: 32077785 DOI: 10.1089/met.2019.0120] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Heparin-binding EGF-like growth factor (HB-EGF) is an EGF family member that interacts with epidermal growth factor receptor (EGFR) and ERBB4. Since HB-EGF was first identified as a novel growth factor secreted from a human macrophage cell line, numerous pathological and physiological functions related to cell proliferation, migration, and inflammation have been reported. Notably, the expression of HB-EGF is sensitively upregulated by oxidative stress in the endothelial cells and functions for auto- and paracrine-EGFR signaling. Overnutrition and obesity cause elevation of HB-EGF expression and EGFR signaling in the hepatic and vascular systems. Modulations of HB-EGF signaling showed a series of protections against phenotypes related to metabolic syndrome and advanced metabolic diseases, suggesting HB-EGF as a potential target against metabolic diseases.
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Affiliation(s)
- Seonwook Kim
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Venkateswaran Subramanian
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA.,Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Ahmed Abdel-Latif
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA.,Department of Medicine-Cardiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Sangderk Lee
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, USA
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Eum JY, Lee GB, Yi SS, Kim IY, Seong JK, Moon MH. Lipid alterations in the skeletal muscle tissues of mice after weight regain by feeding a high-fat diet using nanoflow ultrahigh performance liquid chromatography-tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2020; 1141:122022. [PMID: 32062368 DOI: 10.1016/j.jchromb.2020.122022] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/10/2020] [Accepted: 02/06/2020] [Indexed: 12/20/2022]
Abstract
This study investigated lipid alterations in muscle tissues [gastrocnemius (Gas) and soleus (Sol)] of mice under different diet programs (weight gain, weight maintenance, weight regain, and controls) by nanoflow ultrahigh pressure liquid chromatography-electrospray ionization-tandem mass spectrometry. Since overloaded lipids in the skeletal muscle tissues by excessive fat accumulation are related to insulin resistance leading to type II diabetes mellitus, analysis of lipid alteration in muscle tissues with respect to high-fat diet (HFD) is important to understand obesity related diseases. A total of 345 individual lipid species were identified with their molecular structures, and 184 lipids were quantified by selected reaction monitoring method. Most triacylglycerol (TG) and phosphatidylethanolamine (PE) species displayed a significant (>2-fold, p < 0.01) increase in both the Gas and Sol and to a larger degree in the Gas. However, lipid classes involved in insulin resistance and anti-inflammatory response, including lysophosphatidylcholine (18:0), diacylglycerol (16:0_18:1, 16:0_18:2, and 18:1_18:1), ceramide (d18:1/24:0 and d18:1/24:1), and phosphatidylinositol (18:0/20:4), showed a significant accumulation in the Sol exclusively after HFD treatment. In addition, the lipid profiles were not significantly altered in mice that were fed HFD only for the last 4 weeks (weight gain group), suggesting that consuming HFD in the younger age period can be more effective in the Gas. This study reveals that lipid classes related to insulin resistance accumulated more in the Sol than in the Gas following HFD treatment and the weight regain program perturbed lipid profiles of the Sol to a greater extent than that by the other diet programs, confirming that the Sol tissue is more influenced by HFD than Gas.
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Affiliation(s)
- Jung Yong Eum
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Gwang Bin Lee
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Sun Shin Yi
- Department of Biomedical Laboratory Science, College of Biomedical Sciences, Soonchunhyang University, Asan, Republic of Korea; Korea Mouse Phenotyping Center, Seoul National University, Seoul, Republic of Korea
| | - Il Yong Kim
- Korea Mouse Phenotyping Center, Seoul National University, Seoul, Republic of Korea; Laboratory of Developmental Biology and Genomics, Research Institute for Veterinary Science, and BK21 Program for Creative Veterinary Science, College of Veterinary Medicine, Interdisciplinary Program for Bioinformatics, and BIO-MAX Institute, Seoul National University, Seoul, Republic of Korea
| | - Je Kyung Seong
- Korea Mouse Phenotyping Center, Seoul National University, Seoul, Republic of Korea; Laboratory of Developmental Biology and Genomics, Research Institute for Veterinary Science, and BK21 Program for Creative Veterinary Science, College of Veterinary Medicine, Interdisciplinary Program for Bioinformatics, and BIO-MAX Institute, Seoul National University, Seoul, Republic of Korea.
| | - Myeong Hee Moon
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea.
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Tseng HC, Lin CC, Hsiao LD, Yang CM. Lysophosphatidylcholine-induced mitochondrial fission contributes to collagen production in human cardiac fibroblasts. J Lipid Res 2019; 60:1573-1589. [PMID: 31363041 PMCID: PMC6718437 DOI: 10.1194/jlr.ra119000141] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/26/2019] [Indexed: 12/12/2022] Open
Abstract
Lysophosphatidylcholine (LPC) may accumulate in the heart to cause fibrotic events, which is mediated through fibroblast activation and collagen accumulation. Here, we evaluated the mechanisms underlying LPC-mediated collagen induction via mitochondrial events in human cardiac fibroblasts (HCFs), coupling application of the pharmacologic cyclooxygenase-2 (COX-2) inhibitor, celecoxib, and genetic mutations in FOXO1 on the fibrosis pathway. In HCFs, LPC caused prostaglandin E2 (PGE2)/PGE2 receptor 4 (EP4)-dependent collagen induction via activation of transcriptional activity of forkhead box protein O1 (FoxO1) on COX-2 gene expression. These responses were mediated through LPC-induced generation of mitochondrial reactive oxygen species (mitoROS), as confirmed by ex vivo studies, which indicated that LPC increased COX-2 expression and oxidative stress. LPC-induced mitoROS mediated the activation of protein kinase C (PKC)α, which interacted with and phosphorylated dynamin-related protein 1 (Drp1) at Ser616, thereby increasing Drp1-mediated mitochondrial fission and mitochondrial depolarization. Furthermore, inhibition of PKCα and Drp1 reduced FoxO1-mediated phosphorylation at Ser256 and nuclear accumulation, which suppressed COX-2/PGE2 expression and collagen production. Moreover, pretreatment with celecoxib or COX-2 siRNA suppressed WT FoxO1; mutated Ser256-to-Asp256 FoxO1-enhanced collagen induction, which was reversed by addition of PGE2 Our results demonstrate that LPC-induced generation of mitoROS regulates PKCα-mediated Drp1-dependent mitochondrial fission and COX-2 expression via a PKCα/Drp1/FoxO1 cascade, leading to PGE2/EP4-mediated collagen induction. These findings provide new insights about the role of LPC in the pathway of fibrotic injury in HCFs.
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Affiliation(s)
- Hui-Ching Tseng
- Graduate Institute of Biomedical Sciences, College of Medicine, and Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chih-Chung Lin
- Department of Anesthetics Chang Gung Memorial Hospital, Linkuo, Taiwan and Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Li-Der Hsiao
- Department of Anesthetics Chang Gung Memorial Hospital, Linkuo, Taiwan and Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chuen-Mao Yang
- Graduate Institute of Biomedical Sciences, College of Medicine, and Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan; Department of Anesthetics Chang Gung Memorial Hospital, Linkuo, Taiwan and Chang Gung University, Kwei-San, Tao-Yuan, Taiwan; Research Center for Chinese Herbal Medicine and Research Center for Food and Cosmetic Safety College of Human Ecology, Chang Gung University of Science and Technology, Tao-Yuan, Taiwan; Department of Pharmacology, College of Medicine, China Medical University, Taichung, Taiwan.
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Singh AB, Kan CFK, Kraemer FB, Sobel RA, Liu J. Liver-specific knockdown of long-chain acyl-CoA synthetase 4 reveals its key role in VLDL-TG metabolism and phospholipid synthesis in mice fed a high-fat diet. Am J Physiol Endocrinol Metab 2019; 316:E880-E894. [PMID: 30721098 PMCID: PMC6580179 DOI: 10.1152/ajpendo.00503.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Long-chain acyl-CoA synthetase 4 (ACSL4) has a unique substrate specificity for arachidonic acid. Hepatic ACSL4 is coregulated with the phospholipid (PL)-remodeling enzyme lysophosphatidylcholine (LPC) acyltransferase 3 by peroxisome proliferator-activated receptor δ to modulate the plasma triglyceride (TG) metabolism. In this study, we investigated the acute effects of hepatic ACSL4 deficiency on lipid metabolism in adult mice fed a high-fat diet (HFD). Adenovirus-mediated expression of a mouse ACSL4 shRNA (Ad-shAcsl4) in the liver of HFD-fed mice led to a 43% reduction of hepatic arachidonoyl-CoA synthetase activity and a 53% decrease in ACSL4 protein levels compared with mice receiving control adenovirus (Ad-shLacZ). Attenuated ACSL4 expression resulted in a substantial decrease in circulating VLDL-TG levels without affecting plasma cholesterol. Lipidomics profiling revealed that knocking down ACSL4 altered liver PL compositions, with the greatest impact on accumulation of abundant LPC species (LPC 16:0 and LPC 18:0) and lysophosphatidylethanolamine (LPE) species (LPE 16:0 and LPE 18:0). In addition, fasting glucose and insulin levels were higher in Ad-shAcsl4-transduced mice versus control (Ad-shLacZ). Glucose tolerance testing further indicated an insulin-resistant phenotype upon knockdown of ACSL4. These results provide the first in vivo evidence that ACSL4 plays a role in plasma TG and glucose metabolism and hepatic PL synthesis of hyperlipidemic mice.
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Affiliation(s)
- Amar B Singh
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Chin Fung K Kan
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
- Ochsner Clinical School, University of Queensland School of Medicine , New Orleans, Louisiana
| | - Fredric B Kraemer
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
- Department of Medicine, Stanford University School of Medicine , Stanford, California
- Stanford Diabetes Research Center, Stanford University School of Medicine , Stanford, California
| | - Raymond A Sobel
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
- Department of Pathology, Stanford University School of Medicine , Stanford, California
| | - Jingwen Liu
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
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Surowiec I, Noordam R, Bennett K, Beekman M, Slagboom PE, Lundstedt T, van Heemst D. Metabolomic and lipidomic assessment of the metabolic syndrome in Dutch middle-aged individuals reveals novel biological signatures separating health and disease. Metabolomics 2019; 15:23. [PMID: 30830468 PMCID: PMC6373335 DOI: 10.1007/s11306-019-1484-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 01/31/2019] [Indexed: 12/23/2022]
Abstract
BACKGROUND We aimed to identify novel metabolite and lipid signatures connected with the metabolic syndrome in a Dutch middle-aged population. METHODS 115 individuals with a metabolic syndrome score ranging from 0 to 5 [50 cases of the metabolic syndrome (score ≥ 3) and 65 controls] were enrolled from the Leiden Longevity Study, and LC/GC-MS metabolomics and lipidomics profiling were performed on fasting plasma samples. Data were analysed with principal component analysis and orthogonal projections to latent structures (OPLS) to study metabolite/lipid signatures associated with the metabolic syndrome. In addition, univariate analyses were done with linear regression, adjusted for age and sex, for the study of individual metabolites/lipids in relation to the metabolic syndrome. RESULTS Data was available on 103 metabolites and 223 lipids. In the OPLS model with metabolic syndrome score (Y-variable), 9 metabolites were negatively correlated and 26 metabolites (mostly acylcarnitines, amino acids and keto acids) were positively correlated with the metabolic syndrome score. In addition, a total of 100 lipids (mainly triacylglycerides) were positively correlated and 10 lipids from different lipid classes were negatively correlated with the metabolic syndrome score. In the univariate analyses, the metabolic syndrome (score) was associated with multiple individual metabolites (e.g., valeryl carnitine, pyruvic acid, lactic acid, alanine) and lipids [e.g., diglyceride(34:1), diglyceride(36:2)]. CONCLUSION In this first study on metabolomics/lipidomics of the metabolic syndrome, we identified multiple novel metabolite and lipid signatures, from different chemical classes, that were connected to the metabolic syndrome and are of interest to cardiometabolic disease biology.
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Affiliation(s)
| | - Raymond Noordam
- AcureOmics AB, Umeå, Sweden
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands
| | | | - Marian Beekman
- Department of Medical Statistics and Bioinformatics, Section of Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands
| | - P Eline Slagboom
- Department of Medical Statistics and Bioinformatics, Section of Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Diana van Heemst
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands.
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Impact of serum cholesterol esterification rates on the development of diabetes mellitus in a general population. Lipids Health Dis 2018; 17:180. [PMID: 30055622 PMCID: PMC6064622 DOI: 10.1186/s12944-018-0822-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/10/2018] [Indexed: 11/12/2022] Open
Abstract
Background Lecithin:cholesterol acyltransferase (LCAT) plays an important role in cholesterol esterification in serum. Serum LCAT activity is elevated in patients with serum high triglyceride and low high-density lipoprotein-cholesterol (HDL-C) concentrations, both of which are related to metabolic syndrome and subsequent diabetes mellitus, referred to as lipotoxicity. We hypothesized that increased serum LCAT activity could predict future risk of diabetes mellitus in a general Japanese population. Methods We prospectively studied 1496 individuals aged 20–86 years without histories of diabetes mellitus at baseline. Serum lipid concentrations, glucose parameters, and LCAT activity measured as the serum cholesterol esterification rate, were evaluated. Results During 11 years of follow-up, 46 newly diagnosed patients with diabetes mellitus were reported. After adjustment for plasma glycosylated hemoglobin A1c (HbA1c) levels, the relative risks (RRs) for the development of diabetes mellitus were 5.45 [95% confidence interval (95% CI) 2.37–12.55; P < 0.001] for body-mass index, 0.22 (95% CI, 0.09–0.53; P = 0.001) for HDL-C, 4.81 (95% CI, 1.96–11.77; P = 0.001) for triglyceride, and 4.64 (95% CI, 1.89–11.41; P = 0.001) for LCAT activity. After adjustment for HbA1c, total cholesterol, triglyceride, HDL-C, phospholipid, and free fatty acid levels, the RR of LCAT activity for future risk of diabetes mellitus remained significant (RR, 4.93; 95% CI,1.32–18.41; P = 0.018). In this analysis, we found a significant association between LCAT activity and risk of diabetes mellitus in men but not in women. Conclusion Increased serum cholesterol esterification rate is a potent predictor for future diabetes mellitus.
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Pantophlet AJ, Roelofsen H, de Vries MP, Gerrits WJJ, van den Borne JJGC, Vonk RJ. The use of metabolic profiling to identify insulin resistance in veal calves. PLoS One 2017; 12:e0179612. [PMID: 28617863 PMCID: PMC5472311 DOI: 10.1371/journal.pone.0179612] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 05/31/2017] [Indexed: 11/30/2022] Open
Abstract
Heavy veal calves (4–6 months old) are at risk of developing insulin resistance and disturbed glucose homeostasis. Prolonged insulin resistance could lead to metabolic disorders and impaired growth performance. Recently, we discovered that heavy Holstein-Friesian calves raised on a high-lactose or high-fat diet did not differ in insulin sensitivity, that insulin sensitivity was low and 50% of the calves could be considered insulin resistant. Understanding the patho-physiological mechanisms underlying insulin resistance and discovering biomarkers for early diagnosis would be useful for developing prevention strategies. Therefore, we explored plasma metabolic profiling techniques to build models and discover potential biomarkers and pathways that can distinguish between insulin resistant and moderately insulin sensitive veal calves. The calves (n = 14) were classified as insulin resistant (IR) or moderately insulin sensitive (MIS) based on results from a euglycemic-hyperinsulinemic clamp, using a cut-off value (M/I-value <4.4) to identify insulin resistance. Metabolic profiles of fasting plasma samples were analyzed using reversed phase (RP) and hydrophilic interaction (HILIC) liquid chromatography–mass spectrometry (LC-MS). Orthogonal partial least square discriminant analysis was performed to compare metabolic profiles. Insulin sensitivity was on average 2.3x higher (P <0.001) in MIS than IR group. For both RP-LC-MS and HILIC-LC-MS satisfactory models were build (R2Y >90% and Q2Y >66%), which allowed discrimination between MIS and IR calves. A total of 7 and 20 metabolic features (for RP-LC-MS and HILIC-LC-MS respectively) were most responsible for group separation. Of these, 7 metabolites could putatively be identified that differed (P <0.05) between groups (potential biomarkers). Pathway analysis indicated disturbances in glycerophospholipid and sphingolipid metabolism, the glycine, serine and threonine metabolism, and primary bile acid biosynthesis. These results demonstrate that plasma metabolic profiling can be used to identify insulin resistance in veal calves and can lead to underlying mechanisms.
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Affiliation(s)
- Andre J Pantophlet
- Department of Pediatrics; Center for Liver, Digestive and Metabolic Diseases, University Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Han Roelofsen
- Medical Biomics, University Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Marcel P de Vries
- Department of Pediatrics; Center for Liver, Digestive and Metabolic Diseases, University Groningen, University Medical Centre Groningen, Groningen, The Netherlands.,Medical Biomics, University Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Walter J J Gerrits
- Animal Nutrition Group, Wageningen University, Wageningen, The Netherlands
| | | | - Roel J Vonk
- Medical Biomics, University Groningen, University Medical Centre Groningen, Groningen, The Netherlands
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11
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Ang JE, Pandher R, Ang JC, Asad YJ, Henley AT, Valenti M, Box G, de Haven Brandon A, Baird RD, Friedman L, Derynck M, Vanhaesebroeck B, Eccles SA, Kaye SB, Workman P, de Bono JS, Raynaud FI. Plasma Metabolomic Changes following PI3K Inhibition as Pharmacodynamic Biomarkers: Preclinical Discovery to Phase I Trial Evaluation. Mol Cancer Ther 2016; 15:1412-24. [PMID: 27048952 PMCID: PMC5321508 DOI: 10.1158/1535-7163.mct-15-0815] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 03/29/2016] [Indexed: 12/30/2022]
Abstract
PI3K plays a key role in cellular metabolism and cancer. Using a mass spectrometry-based metabolomics platform, we discovered that plasma concentrations of 26 metabolites, including amino acids, acylcarnitines, and phosphatidylcholines, were decreased in mice bearing PTEN-deficient tumors compared with non-tumor-bearing controls and in addition were increased following dosing with class I PI3K inhibitor pictilisib (GDC-0941). These candidate metabolomics biomarkers were evaluated in a phase I dose-escalation clinical trial of pictilisib. Time- and dose-dependent effects were observed in patients for 22 plasma metabolites. The changes exceeded baseline variability, resolved after drug washout, and were recapitulated on continuous dosing. Our study provides a link between modulation of the PI3K pathway and changes in the plasma metabolome and demonstrates that plasma metabolomics is a feasible and promising strategy for biomarker evaluation. Also, our findings provide additional support for an association between insulin resistance, branched-chain amino acids, and related metabolites following PI3K inhibition. Mol Cancer Ther; 15(6); 1412-24. ©2016 AACR.
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Affiliation(s)
- Joo Ern Ang
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom. Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, United Kingdom
| | - Rupinder Pandher
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Joo Chew Ang
- School of Physics, University of Melbourne, Melbourne, Victoria, Australia
| | - Yasmin J Asad
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Alan T Henley
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Melanie Valenti
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Gary Box
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Alexis de Haven Brandon
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Richard D Baird
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom. Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, United Kingdom
| | | | | | | | - Suzanne A Eccles
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Stan B Kaye
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom. Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, United Kingdom
| | - Paul Workman
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Johann S de Bono
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom. Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, United Kingdom
| | - Florence I Raynaud
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, United Kingdom. Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, United Kingdom.
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12
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Huang JP, Cheng ML, Wang CH, Shiao MS, Chen JK, Hung LM. High-fructose and high-fat feeding correspondingly lead to the development of lysoPC-associated apoptotic cardiomyopathy and adrenergic signaling-related cardiac hypertrophy. Int J Cardiol 2016; 215:65-76. [PMID: 27107546 DOI: 10.1016/j.ijcard.2016.03.239] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 03/03/2016] [Accepted: 03/26/2016] [Indexed: 01/10/2023]
Abstract
BACKGROUND The heart is a highly adaptive organ that demonstrates remarkable structural, functional, and metabolic remodeling in response to physiological and pathological stimuli. We hypothesize that the heart undergoes differential adaptations in high-fat and high-fructose diet, resulting in a distinct phenotype. METHODS High-fat and high-fructose diet-induced obese and non-obese insulin resistance (IR) rat models were used to understand how the heart adapts to long-term (12-week) overnutrition. RESULTS Rats fed the high-fat diet developed obese IR, whereas high-fructose diet developed non-obese IR. Obese IR rats developed fibrotic hypertrophy with impairment of preload-independent contractility. The sympathetic and renin-angiotensin-aldosterone (RAA) systems and myocardial adrenergic signaling were activated in obese IR rats. Non-obese IR rats developed apoptotic cardiomyopathy with severe systolic dysfunction. Myocardial calcium cycling regulatory proteins (CCRPs) were dysregulated in non-obese IR rats; specifically, troponin I protein expression was downregulated. Moreover, compared with the controls, lipidomics analysis revealed substantial differences in lipid metabolites in non-obese IR and obese IR rats. The overproduction of lysophosphatidylcholine (lysoPC) and fatty acids was observed in non-obese IR rat hearts. A strong correlation was observed between the myocardial lysoPC and plasma troponin I levels. Treatment of cardiomyocytes with lysoPC resulted in cell death in a dose- and time-dependent manner. The overproduction of myocardial lysoPCs was associated with circulating sPLA2 levels. CONCLUSION Obese IR rats developed severe fibrotic hypertrophy with the activation of adrenergic signaling and sympathetic and RAA systems. The sPLA2-lysoPC may play a crucial role in the induction of apoptotic cardiomyopathy in high fructose-induced non-obese IR rats.
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Affiliation(s)
- Jiung-Pang Huang
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Center for Healthy and Aging Research, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Mei-Ling Cheng
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Center for Healthy and Aging Research, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Heart Failure Center, Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Chao-Hung Wang
- Heart Failure Center, Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Ming-Shi Shiao
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Center for Healthy and Aging Research, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Jan-Kan Chen
- Center for Healthy and Aging Research, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Department of Physiology and Pharmacology, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Li-Man Hung
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Center for Healthy and Aging Research, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; Heart Failure Center, Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan.
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Paoletti L, Domizi P, Marcucci H, Montaner A, Krapf D, Salvador G, Banchio C. Lysophosphatidylcholine Drives Neuroblast Cell Fate. Mol Neurobiol 2015; 53:6316-6331. [DOI: 10.1007/s12035-015-9528-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/05/2015] [Indexed: 12/31/2022]
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14
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Zukaite V, Cook RT, Walker AJ. Multiple roles for protein kinase C in gastropod embryogenesis. Cell Tissue Res 2015; 364:117-24. [DOI: 10.1007/s00441-015-2288-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 08/27/2015] [Indexed: 02/06/2023]
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15
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Mangum LC, Borazjani A, Stokes JV, Matthews AT, Lee JH, Chambers JE, Ross MK. Organochlorine insecticides induce NADPH oxidase-dependent reactive oxygen species in human monocytic cells via phospholipase A2/arachidonic acid. Chem Res Toxicol 2015; 28:570-84. [PMID: 25633958 DOI: 10.1021/tx500323h] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Bioaccumulative organohalogen chemicals, such as organochlorine (OC) insecticides, have been increasingly associated with disease etiology; however, the mechanistic link between chemical exposure and diseases, such as atherosclerosis, cancer, and diabetes, is complex and poorly defined. Systemic oxidative stress stemming from OC exposure might play a vital role in the development of these pathologies. Monocytes are important surveillance cells of the innate immune system that respond to extracellular signals possessing danger-associated molecular patterns by synthesizing oxyradicals, such as superoxide, for the purpose of combating infectious pathogens. We hypothesized that OC chemicals can be toxic to monocytes because of an inappropriate elevation in superoxide-derived reactive oxygen species (ROS) capable of causing cellular oxidative damage. Reactive oxyradicals are generated in monocytes in large part by NADPH oxidase (Nox). The present study was conducted to examine the ability of two chlorinated cyclodiene compounds, trans-nonachlor and dieldrin, as well as p,p'-DDE, a chlorinated alicyclic metabolite of DDT, to stimulate Nox activity in a human monocytic cell line and to elucidate the mechanisms for this activation. Human THP-1 monocytes treated with either trans-nonachlor or dieldrin (0.1-10 μM in the culture medium) exhibited elevated levels of intracellular ROS, as evidenced by complementary methods, including flow cytometry analysis using the probe DCFH-DA and hydroethidine-based fluorometric and UPLC-MS assays. In addition, the induced reactive oxygen flux caused by trans-nonachlor was also observed in two other cell lines, murine J774 macrophages and human HL-60 cells. The central role of Nox in OC-mediated oxidative stress was demonstrated by the attenuated superoxide production in OC-exposed monocytes treated with the Nox inhibitors diphenyleneiodonium and VAS-2870. Moreover, monocytes challenged with OCs exhibited increased phospho-p47(phox) levels and enhanced p47(phox) membrane localization compared to that in vehicle-treated cells. p47(phox) is a cytosolic regulatory subunit of Nox, and its phosphorylation and translocation to the NOX2 catalytic subunit in membranes is a requisite step for Nox assembly and activation. Dieldrin and trans-nonachlor treatments of monocytes also resulted in marked increases in arachidonic acid (AA) and eicosanoid production, which could be abrogated by the phospholipase A2 (PLA2) inhibitor arachidonoyltrifluoromethyl ketone (ATK) but not by calcium-independent PLA2 inhibitor bromoenol lactone. This suggested that cytosolic PLA2 plays a crucial role in the induction of Nox activity by increasing the intracellular pool of AA that activates protein kinase C, which phosphorylates p47(phox). In addition, ATK also blocked OC-induced p47(phox) serine phosphorylation and attenuated ROS levels, which further supports the notion that the AA pool liberated by cytosolic PLA2 is responsible for Nox activation. Together, the results suggest that trans-nonachlor and dieldrin are capable of increasing intracellular superoxide levels via a Nox-dependent mechanism that relies on elevated intracellular AA levels. These findings are significant because chronic activation of monocytes by environmental toxicants might contribute to pathogenic oxidative stress and inflammation.
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Affiliation(s)
- Lee C Mangum
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
| | - Abdolsamad Borazjani
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
| | - John V Stokes
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
| | - Anberitha T Matthews
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
| | - Jung Hwa Lee
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
| | - Janice E Chambers
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
| | - Matthew K Ross
- Department of Basic Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762, United States
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16
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Zhang XY, Yang BY, Wang JY, Mo X, Zhang J, Hua ZC. FADD is essential for glucose uptake and survival of thymocytes. Biochem Biophys Res Commun 2014; 451:202-7. [PMID: 25078620 DOI: 10.1016/j.bbrc.2014.07.092] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 11/20/2022]
Abstract
Fas-associated protein with death domain (FADD) has been implicated in T lymphocytes, but the nature of FADD-dependent mechanism in early T cell development has not been completely elucidated. In this study, using T-cell specific deletion mice, we observed that FADD deficiency in thymocytes led to increased apoptosis and reduced cell numbers, which may be attributed to the reduction of Glut1 expression and correspondingly decreased glucose uptake. Furthermore, an abnormal transduction of Akt signaling was discovered in FADD(-/-) thymocytes, which may be responsible for the declined Glut1 expression. Collectively, our results demonstrate the new function of FADD in glucose metabolism and survival of early T cells.
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Affiliation(s)
- Xiang-Yu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, PR China
| | - Bing-Ya Yang
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, PR China
| | - Jia-Yu Wang
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, PR China
| | - Xuan Mo
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, PR China
| | - Jing Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, PR China
| | - Zi-Chun Hua
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, PR China; Changzhou High-Tech Research Institute of Nanjing University and Jiangsu Target-Pharma Laboratories Inc., Changzhou 213164, Jiangsu, PR China.
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17
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Munir KM, Chandrasekaran S, Gao F, Quon MJ. Mechanisms for food polyphenols to ameliorate insulin resistance and endothelial dysfunction: therapeutic implications for diabetes and its cardiovascular complications. Am J Physiol Endocrinol Metab 2013; 305:E679-86. [PMID: 23900418 PMCID: PMC4073986 DOI: 10.1152/ajpendo.00377.2013] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The rising epidemic of diabetes is a pressing issue in clinical medicine worldwide from both healthcare and economic perspectives. This is fueled by overwhelming increases in the incidence and prevalence of obesity. Obesity and diabetes are characterized by both insulin resistance and endothelial dysfunction that lead to substantial increases in cardiovascular morbidity and mortality. Reciprocal relationships between insulin resistance and endothelial dysfunction tightly link metabolic diseases including obesity and diabetes with their cardiovascular complications. Therefore, therapeutic approaches that target either insulin resistance or endothelial dysfunction alone are likely to simultaneously improve both metabolic and cardiovascular pathophysiology and disease outcomes. Moreover, combination therapies with agents targeting distinct mechanisms are likely to have additive or synergistic benefits. Conventional therapies for diabetes and its cardiovascular complications that are both safe and effective are insufficient to meet rising demand. Large, robust, epidemiologic studies demonstrate beneficial metabolic and cardiovascular health effects for many functional foods containing various polyphenols. However, precise molecular mechanisms of action for food polyphenols are largely unknown. Moreover, translation of these insights into effective clinical therapies has not been fully realized. Nevertheless, some functional foods are likely sources for safe and effective therapies and preventative strategies for metabolic diseases and their cardiovascular complications. In this review, we emphasize recent progress in elucidating molecular, cellular, and physiological actions of polyphenols from green tea (EGCG), cocoa (ECG), and citrus fruits (hesperedin) that are related to improving metabolic and cardiovascular pathophysiology. We also discuss a rigorous comprehensive approach to studying functional foods that is essential for developing novel, effective, and safe medications derived from functional foods that will complement existing conventional drugs.
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Affiliation(s)
- Kashif M Munir
- Division of Endocrinology, Diabetes, and Nutrition, University of Maryland School of Medicine, Baltimore, Maryland; and
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18
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Mima A. Diabetic nephropathy: protective factors and a new therapeutic paradigm. J Diabetes Complications 2013; 27:526-30. [PMID: 23619194 DOI: 10.1016/j.jdiacomp.2013.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 02/25/2013] [Accepted: 03/19/2013] [Indexed: 10/26/2022]
Abstract
Diabetic nephropathy (DN) is the most common cause of chronic kidney disease (CKD) and its number has been increasing. CKD is a worldwide threat to health but the precise mechanism of this problem is not fully appreciated. It is believed that hyperglycemia is one of the most important metabolic factors in the development of DN. Multiple molecular mechanisms have been proposed to mediate hyperglycemia's adverse effects on kidney. To identify targets for therapeutic intervention, most studies have focused on understanding how abnormal levels of such metabolities cause DN. However, there have been few reports regarding endogenous renal protective factors. Thus, recognition of the importance of this could be providing a new perspective for understanding the development of DN and a new therapeutic paradigm to combat DN.
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Affiliation(s)
- Akira Mima
- Department of Nephrology, Graduate School of Medicine, Institute of Health Biosciences, University of Tokushima, Tokushima, Japan.
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Rac1 and Stathmin but Not EB1 Are Required for Invasion of Breast Cancer Cells in Response to IGF-I. Int J Cell Biol 2011; 2011:615912. [PMID: 21961005 PMCID: PMC3180068 DOI: 10.1155/2011/615912] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 04/04/2011] [Accepted: 05/23/2011] [Indexed: 11/22/2022] Open
Abstract
Cell migration is considered necessary for the invasion that accompanies the directional formation of the cellular protrusions termed lamellipodia. In invasive breast cancer MDA-MB-231 cells, lamellipodia formation is preceded by translocation of the actin cytoskeletal regulatory protein WAVE2 to the leading edge. WAVE2 translocation and lamellipodia formation require many signaling molecules, including PI3K, Rac1, Pak1, IRSp53, stathmin, and EB1, but whether these molecules are necessary for invasion remains unclear. In noninvasive breast cancer MCF7 cells, no lamellipodia were induced by IGF-I, whereas in MDA-MB-231 cells, Rac1, stathmin, and EB1 were overexpressed. Depletion of Rac1 or stathmin by small interfering RNA abrogated the IGF-I-induced invasion of MDA-MB-231 cells; however, depletion of EB1 did not, indicating the necessity of Rac1 and stathmin but not EB1 for invasion. The signaling pathway leading to cell invasion may not be identical but shares some common molecules, leading to cell migration through lamellipodia formation.
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20
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Han MS, Lim YM, Quan W, Kim JR, Chung KW, Kang M, Kim S, Park SY, Han JS, Park SY, Cheon HG, Dal Rhee S, Park TS, Lee MS. Lysophosphatidylcholine as an effector of fatty acid-induced insulin resistance. J Lipid Res 2011; 52:1234-1246. [PMID: 21447485 DOI: 10.1194/jlr.m014787] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The mechanism of FFA-induced insulin resistance is not fully understood. We have searched for effector molecules(s) in FFA-induced insulin resistance. Palmitic acid (PA) but not oleic acid (OA) induced insulin resistance in L6 myotubes through C-Jun N-terminal kinase (JNK) and insulin receptor substrate 1 (IRS-1) Ser307 phosphorylation. Inhibitors of ceramide synthesis did not block insulin resistance by PA. However, inhibition of the conversion of PA to lysophosphatidylcholine (LPC) by calcium-independent phospholipase A₂ (iPLA₂) inhibitors, such as bromoenol lactone (BEL) or palmitoyl trifluoromethyl ketone (PACOCF₃), prevented insulin resistance by PA. iPLA₂ inhibitors or iPLA₂ small interfering RNA (siRNA) attenuated JNK or IRS-1 Ser307 phosphorylation by PA. PA treatment increased LPC content, which was reversed by iPLA₂ inhibitors or iPLA₂ siRNA. The intracellular DAG level was increased by iPLA₂ inhibitors, despite ameliorated insulin resistance. Pertussis toxin (PTX), which inhibits LPC action through the G-protein coupled receptor (GPCR)/Gα(i), reversed insulin resistance by PA. BEL administration ameliorated insulin resistance and diabetes in db/db mice. JNK and IRS-1Ser307 phosphorylation in the liver and muscle of db/db mice was attenuated by BEL. LPC content was increased in the liver and muscle of db/db mice, which was suppressed by BEL. These findings implicate LPC as an important lipid intermediate that links saturated fatty acids to insulin resistance.
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Affiliation(s)
- Myoung Sook Han
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
| | - Yu-Mi Lim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
| | - Wenying Quan
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
| | - Jung Ran Kim
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Inchon 406-840, Korea
| | - Kun Wook Chung
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
| | - Mira Kang
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
| | - Sunshin Kim
- Carcinogenesis Branch, Korean National Cancer Center, Goyang 410-769, Korea
| | - Sun Young Park
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
| | - Joong-Soo Han
- Institute of Biomedical Science, College of Medicine, Hanyang University, Seoul 133-791, Korea; Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul 133-791, Korea
| | - Shin-Young Park
- Institute of Biomedical Science, College of Medicine, Hanyang University, Seoul 133-791, Korea; Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul 133-791, Korea
| | - Hyae Gyeong Cheon
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Inchon 406-840, Korea
| | - Sang Dal Rhee
- Bio-Organic Science Division, Korea Research Institute of Chemical Technology, Daejon 305-343, Korea
| | - Tae-Sik Park
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Inchon 406-840, Korea.
| | - Myung-Shik Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.
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Jiang F, Zhang Y, Dusting GJ. NADPH oxidase-mediated redox signaling: roles in cellular stress response, stress tolerance, and tissue repair. Pharmacol Rev 2011; 63:218-42. [PMID: 21228261 DOI: 10.1124/pr.110.002980] [Citation(s) in RCA: 430] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
NADPH oxidase (Nox) has a dedicated function of generating reactive oxygen species (ROS). Accumulating evidence suggests that Nox has an important role in signal transduction in cellular stress responses. We have reviewed the current evidence showing that the Nox system can be activated by a collection of chemical, physical, and biological cellular stresses. In many circumstances, Nox activation fits to the cellular stress response paradigm, in that (1) the response can be initiated by various forms of cellular stresses; (2) Nox-derived ROS may activate mitogen-activated protein kinases (extracellular signal-regulated kinase, p38) and c-Jun NH(2)-terminal kinase, which are the core of the cell stress-response signaling network; and (3) Nox is involved in the development of stress cross-tolerance. Activation of the cell survival pathway by Nox may promote cell adaptation to stresses, whereas Nox may also convey signals toward apoptosis in irreversibly injured cells. At later stage after injury, Nox is involved in tissue repair by modulating cell proliferation, angiogenesis, and fibrosis. We suggest that Nox may have an integral role in cell stress responses and the subsequent tissue repair process. Understanding Nox-mediated redox signaling mechanisms may be of prominent significance at the crossroads of directing cellular responses to stress, aiming at either enhancing the stress resistance (in such situations as preventing ischemia-reperfusion injuries and accelerating wound healing) or sensitizing the stress-induced cytotoxicity for proliferative diseases such as cancer. Therefore, an optimal outcome of interventions on Nox will only be achieved when this is dealt with in a timely and disease-and stage-specific manner.
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Affiliation(s)
- Fan Jiang
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Qilu Hospital, Shandong University, 107 Wen Hua Xi Road, Jinan, Shandong 250012, China.
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Ahluwalia M, Donovan H, Singh N, Butcher L, Erusalimsky JD. Anagrelide represses GATA-1 and FOG-1 expression without interfering with thrombopoietin receptor signal transduction. J Thromb Haemost 2010; 8:2252-61. [PMID: 20586925 DOI: 10.1111/j.1538-7836.2010.03970.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Anagrelide is a selective inhibitor of megakaryocytopoiesis used to treat thrombocytosis in patients with chronic myeloproliferative disorders. The effectiveness of anagrelide in lowering platelet counts is firmly established, but its primary mechanism of action remains elusive. OBJECTIVES AND METHODS Here, we have evaluated whether anagrelide interferes with the major signal transduction cascades stimulated by thrombopoietin in the hematopoietic cell line UT-7/mpl and in cultured CD34(+) -derived human hematopoietic cells. In addition, we have used quantitative mRNA expression analysis to assess whether the drug affects the levels of known transcription factors that control megakaryocytopoiesis. RESULTS In UT-7/mpl cells, anagrelide (1μm) did not interfere with MPL-mediated signaling as monitored by its lack of effect on JAK2 phosphorylation. Similarly, the drug did not affect the phosphorylation of STAT3, ERK1/2 or AKT in either UT-7/mpl cells or primary hematopoietic cells. In contrast, during thrombopoietin-induced megakaryocytic differentiation of normal hematopoietic cultures, anagrelide (0.3μm) reduced the rise in the mRNA levels of the transcription factors GATA-1 and FOG-1 as well as those of the downstream genes encoding FLI-1, NF-E2, glycoprotein IIb and MPL. However, the drug showed no effect on GATA-2 or RUNX-1 mRNA expression. Furthermore, anagrelide did not diminish the rise in GATA-1 and FOG-1 expression during erythropoietin-stimulated erythroid differentiation. Cilostamide, an exclusive and equipotent phosphodiesterase III (PDEIII) inhibitor, did not alter the expression of these genes. CONCLUSIONS Anagrelide suppresses megakaryocytopoiesis by reducing the expression levels of GATA-1 and FOG-1 via a PDEIII-independent mechanism that is differentiation context-specific and does not involve inhibition of MPL-mediated early signal transduction events.
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Affiliation(s)
- M Ahluwalia
- University of Wales Institute, Cardiff School of Health Sciences, Cardiff, UK
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23
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Walker AJ, Lacchini AH, Sealey KL, Mackintosh D, Davies AJ. Spreading by snail (Lymnaea stagnalis) defence cells is regulated through integrated PKC, FAK and Src signalling. Cell Tissue Res 2010; 341:131-45. [PMID: 20512591 DOI: 10.1007/s00441-010-0986-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Accepted: 04/21/2010] [Indexed: 12/25/2022]
Abstract
Cell adhesion and spreading are vital to immune function. In molluscs, haemocytes (circulating phagocytes) are sentinels and effectors of the internal defence system; however, molecular mechanisms that regulate integrin-mediated spreading by haemocytes have not been characterised in detail. Visualisation of Lymnaea stagnalis haemocytes by scanning electron microscopy revealed membrane ruffling, formation of lamellipodia and extensive filopodia during early stages of cell adhesion and spreading. These events correlated with increased phosphorylation (activation) of protein kinase C (PKC) and focal adhesion kinase (FAK), sustained for 60 min. Treatment of haemocytes with the PKC inhibitors GF109203X or Gö 6976, or the Src/tyrosine kinase inhibitors SrcI or herbimycin A, attenuated haemocyte spread by 64, 46, 32 and 35%, respectively (P <or= 0.001); PKC or Src inhibition also prevented focal adhesion formation. Western blotting demonstrated that during spreading and adhesion these inhibitors also impaired PKC and FAK activation, with Gö 6976 or SrcI inhibiting FAK phosphorylation by at least 70% (P <or= 0.001), and herbimycin A or SrcI inhibiting PKC phosphorylation by at least 46% (P <or= 0.01). Confocal microscopy revealed phosphorylated PKC colocalised with focal adhesion sites, particularly during early phases of adhesion and spreading. Finally, fibronectin promoted PKC and FAK phosphorylation in suspended haemocytes demonstrating that activation can occur independent of cell adhesion. These novel data are consistent with PKC and FAK/Src playing an integrated role in integrin activation and integrin-mediated spreading by L. stagnalis haemocytes. We propose a model in which integrin engagement mediates association of PKC with FAK/Src complexes to promote focal adhesion assembly during immune recognition by these cells.
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Affiliation(s)
- Anthony J Walker
- School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, UK.
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24
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Ben-Zeev G, Telias M, Nussinovitch I. Lysophospholipids modulate voltage-gated calcium channel currents in pituitary cells; effects of lipid stress. Cell Calcium 2010; 47:514-24. [PMID: 20510448 DOI: 10.1016/j.ceca.2010.04.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 04/28/2010] [Accepted: 04/28/2010] [Indexed: 01/26/2023]
Abstract
Voltage-gated calcium channels (VGCCs) are osmosensitive. The hypothesis that this property of VGCCs stems from their susceptibility to alterations in the mechanical properties of the bilayer was tested on VGCCs in pituitary cells using cone-shaped lysophospholipids (LPLs) to perturb bilayer lipid stress. LPLs of different head group size and charge were used: lysophosphatidylcholine (LPC), lysophosphatidylinositol (LPI), lysophosphatidylserine (LPS) and lysophosphatidylethanolamine (LPE). Phosphatidylcholine (PC) and LPC (C6:0) were used as controls. We show that partition of both LPC and LPI into the membrane of pituitary cells suppressed L-type calcium channel currents (I(L)). This suppression of I(L) was slow in onset, reversible upon washout with BSA and associated with a depolarizing shift in activation ( approximately 8mV). In contrast to these effects of LPC and LPI on I(L), LPS, LPE, PC and LPC (C6:0) exerted minimal or insignificant effects. This difference may be attributed to the prominent conical shape of LPC and LPI compared to the shapes of LPS and LPE (which have smaller headgroups), and to PC (which is cylindrical). The similar effects of LPC and LPI on I(L), despite differences in the structure and charge of their headgroups suggest a common lipid stress dependent mechanism in their action on VGCCs.
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Affiliation(s)
- Galia Ben-Zeev
- Department of Medical Neurobiology, Institute for Medical Research-Israel-Canada, Jerusalem, Israel
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25
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Takahashi K, Tanaka T, Suzuki K. Directional control of WAVE2 membrane targeting by EB1 and phosphatidylinositol 3,4,5-triphosphate. Cell Signal 2010; 22:510-8. [PMID: 19925864 DOI: 10.1016/j.cellsig.2009.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 11/09/2009] [Indexed: 01/30/2023]
Abstract
Membrane targeting of WAVE2 along microtubules is mediated by a motor protein kinesin and requires Pak1, a downstream effector of Rac1. However, the mechanism by which WAVE2 targeting to the leading edge is directionally controlled remains largely unknown. Here we demonstrate that EB1, a microtubule plus-end-binding protein, constitutively associates with stathmin, a microtubule-destabilizing protein, in human breast cancer cells. Stimulation of the cells with insulin-like growth factor I (IGF-I) induced Pak1-dependent binding of the EB1-stathmin complex to microtubules that bear WAVE2 and colocalization of the complex with WAVE2 at the leading edge. Depletion of EB1 by small interfering RNA (siRNA) abrogated the IGF-I-induced WAVE2 targeting and stathmin binding to microtubules. On the other hand, chemotaxis chamber assays indicated that the IGF-I receptor (IGF-IR) was locally activated in the region facing toward IGF-I. In addition, IGF-I caused phosphatidylinositol 3-kinase (PI 3-kinase)-dependent production of phosphatidylinositol 3,4,5-triphosphate (PIP3) near activated IGF-IR and WAVE2 colocalization with it. Collectively, WAVE2-membrane targeting is directionally controlled by binding of the EB1-stathmin complex to WAVE2-bearing microtubules and by the interaction between WAVE2 and PIP3 produced near IGF-IR that is locally activated by IGF-I.
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Affiliation(s)
- Kazuhide Takahashi
- Molecular Cell Biology Division, Kanagawa Cancer Center Research Institute, Yokohama 241-0815, Japan.
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26
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Taboubi S, Garrouste F, Parat F, Pommier G, Faure E, Monferran S, Kovacic H, Lehmann M. Gq-coupled purinergic receptors inhibit insulin-like growth factor-I/phosphoinositide 3-kinase pathway-dependent keratinocyte migration. Mol Biol Cell 2010; 21:946-55. [PMID: 20089844 PMCID: PMC2836975 DOI: 10.1091/mbc.e09-06-0497] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
After skin wound, released growth factors and extracellular nucleotides regulate the different phases of healing, including re-epithelialization. Here, we show that, in keratinocytes, purinergic P2Y2 receptors inhibit the motogenic IGF-I/PI3K pathway. Therefore, extracellular nucleotides may play key roles during skin remodelling after wound. Insulin-like growth factor-I (IGF-I) activation of phosphoinositol 3-kinase (PI3K) is an essential pathway for keratinocyte migration that is required for epidermis wound healing. We have previously reported that activation of Gα(q/11)-coupled-P2Y2 purinergic receptors by extracellular nucleotides delays keratinocyte wound closure. Here, we report that activation of P2Y2 receptors by extracellular UTP inhibits the IGF-I–induced p110α-PI3K activation. Using siRNA and pharmacological inhibitors, we demonstrate that the UTP antagonistic effects on PI3K pathway are mediated by Gα(q/11)—and not G(i/o)—independently of phospholipase Cβ. Purinergic signaling does not affect the formation of the IGF-I receptor/insulin receptor substrate-I/p85 complex, but blocks the activity of a membrane-targeted active p110α mutant, indicating that UTP acts downstream of PI3K membrane recruitment. UTP was also found to efficiently attenuate, within few minutes, the IGF-I–induced PI3K-controlled translocation of the actin-nucleating protein cortactin to the plasma membrane. This supports the UTP ability to alter later migratory events. Indeed, UTP inhibits keratinocyte spreading and migration promoted by either IGF-I or a membrane-targeted active p110α mutant, in a Gα(q/11)-dependent manner both. These findings provide new insight into the signaling cross-talk between receptor tyrosine kinase and Gα(q/11)-coupled receptors, which mediate opposite effects on p110α-PI3K activity and keratinocyte migration.
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Affiliation(s)
- Salma Taboubi
- INSERM UMR 911, Centre de Recherche en Oncologie Biologique et en Oncopharmacologie, Université Aix-Marseille, Marseille 13005, France
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Cheng L, Han X, Shi Y. A regulatory role of LPCAT1 in the synthesis of inflammatory lipids, PAF and LPC, in the retina of diabetic mice. Am J Physiol Endocrinol Metab 2009; 297:E1276-82. [PMID: 19773578 PMCID: PMC2793047 DOI: 10.1152/ajpendo.00475.2009] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Platelet-activating factor (PAF) and lysophosphatidylcholine (LPC) are potent inflammatory lipids. Elevated levels of PAF and LPC are associated with the onset of diabetic retinopathy and neurodegeneration. However, the molecular mechanisms underlying such defects remain elusive. LPCAT1 is a newly reported lysophospholipid acyltransferase implicated in the anti-inflammatory response by its role in conversion of LPC to PC. Intriguingly, the LPCAT1 enzyme also catalyzes the synthesis of PAF from lyso-PAF with use of acetyl-CoA as a substrate. The present studies investigated regulatory roles of LPCAT1 in the synthesis of inflammatory lipids during the onset of diabetes. Our work shows that LPCAT1 plays an important role in the inactivation of PAF by catalyzing the synthesis of alkyl-PC, an inactivated form of PAF with use of acyl-CoA and lyso-PAF as substrates. In support of a role of LPCAT1 in anti-inflammatory responses in diabetic retinopathy, LPCAT1 is most abundantly expressed in the retina. Moreover, LPCAT1 mRNA levels and acyltransferase activity toward lyso-PAF and LPC were significantly downregulated in retina and brain tissues in response to the onset of diabetes in Ins2(Akita) and db/db mice, mouse models of type 1 and type 2 diabetes, respectively. Conversely, treatment of db/db mice with rosiglitazone, an antidiabetes compound, significantly upregulated LPCAT1 mRNA levels concurrently with increased acyltransferase activity in the retina and brain. Collectively, these findings identified a novel regulatory role of LPCAT1 in catalyzing the inactivation of inflammatory lipids in the retina of diabetic mice.
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Affiliation(s)
- Long Cheng
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA
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28
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Protein kinase C signalling during miracidium to mother sporocyst development in the helminth parasite, Schistosoma mansoni. Int J Parasitol 2009; 39:1223-33. [DOI: 10.1016/j.ijpara.2009.04.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 03/31/2009] [Accepted: 04/02/2009] [Indexed: 12/27/2022]
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Berna MJ, Tapia JA, Sancho V, Thill M, Pace A, Hoffmann KM, Gonzalez-Fernandez L, Jensen RT. Gastrointestinal growth factors and hormones have divergent effects on Akt activation. Cell Signal 2009; 21:622-38. [PMID: 19166928 PMCID: PMC2677382 DOI: 10.1016/j.cellsig.2009.01.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 12/16/2008] [Accepted: 01/02/2009] [Indexed: 12/11/2022]
Abstract
Akt is a central regulator of apoptosis, cell growth and survival. Growth factors and some G-protein-coupled receptors (GPCR) regulate Akt. Whereas growth-factor activation of Akt has been extensively studied, the regulation of Akt by GPCR's, especially gastrointestinal hormones/neurotransmitters, remains unclear. To address this area, in this study the effects of GI growth factors and hormones/neurotransmitters were investigated in rat pancreatic acinar cells which are high responsive to these agents. Pancreatic acini expressed Akt and 5 of 7 known pancreatic growth-factors stimulate Akt phosphorylation (T308, S473) and translocation. These effects are mediated by p85 phosphorylation and activation of PI3K. GI hormones increasing intracellular cAMP had similar effects. However, GI-hormones/neurotransmitters [CCK, bombesin, carbachol] activating phospholipase C (PLC) inhibited basal and growth-factor-stimulated Akt activation. Detailed studies with CCK, which has both physiological and pathophysiological effects on pancreatic acinar cells at different concentrations, demonstrated CCK has a biphasic effect: at low concentrations (pM) stimulating Akt by a Src-dependent mechanism and at higher concentrations (nM) inhibited basal and stimulated Akt translocation, phosphorylation and activation, by de-phosphorylating p85 resulting in decreasing PI3K activity. This effect required activation of both limbs of the PLC-pathway and a protein tyrosine phosphatase, but was not mediated by p44/42 MAPK, Src or activation of a serine phosphatase. Akt inhibition by CCK was also found in vivo and in Panc-1 cancer cells where it inhibited serum-mediated rescue from apoptosis. These results demonstrate that GI growth factors as well as gastrointestinal hormones/neurotransmitters with different cellular basis of action can all regulate Akt phosphorylation in pancreatic acinar cells. This regulation is complex with phospholipase C agents such as CCK, because both stimulatory and inhibitory effects can be seen, which are mediated by different mechanisms.
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Affiliation(s)
- Marc J. Berna
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1804, USA
- Universitätsklinikum Eppendorf, Medizinische Klinik I, 20246 Hamburg, Germany
| | - Jose A. Tapia
- Departamento de Fisiologia, Universidad de Extremadura, Cáceres 10071, Spain
| | - Veronica Sancho
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1804, USA
| | - Michelle Thill
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892
- Universitätsklinikum Eppendorf, Klinik und Poliklinik für Augenheilkunde, 20246 Hamburg, Germany
| | - Andrea Pace
- Universitätsklinikum Eppendorf, Medizinische Klinik I, 20246 Hamburg, Germany
| | - K. Martin Hoffmann
- Department of Pediatrics and Adolescent Medicine, Medical University of Graz, Auenbruggerplatz 30, A-8036 Graz, Austria
| | | | - Robert T. Jensen
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1804, USA
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Pietiläinen KH, Naukkarinen J, Rissanen A, Saharinen J, Ellonen P, Keränen H, Suomalainen A, Götz A, Suortti T, Yki-Järvinen H, Orešič M, Kaprio J, Peltonen L. Global transcript profiles of fat in monozygotic twins discordant for BMI: pathways behind acquired obesity. PLoS Med 2008; 5:e51. [PMID: 18336063 PMCID: PMC2265758 DOI: 10.1371/journal.pmed.0050051] [Citation(s) in RCA: 227] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 01/10/2008] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The acquired component of complex traits is difficult to dissect in humans. Obesity represents such a trait, in which the metabolic and molecular consequences emerge from complex interactions of genes and environment. With the substantial morbidity associated with obesity, a deeper understanding of the concurrent metabolic changes is of considerable importance. The goal of this study was to investigate this important acquired component and expose obesity-induced changes in biological pathways in an identical genetic background. METHODS AND FINDINGS We used a special study design of "clonal controls," rare monozygotic twins discordant for obesity identified through a national registry of 2,453 young, healthy twin pairs. A total of 14 pairs were studied (eight male, six female; white), with a mean +/- standard deviation (SD) age 25.8 +/- 1.4 y and a body mass index (BMI) difference 5.2 +/- 1.8 kg/m(2). Sequence analyses of mitochondrial DNA (mtDNA) in subcutaneous fat and peripheral leukocytes revealed no aberrant heteroplasmy between the co-twins. However, mtDNA copy number was reduced by 47% in the obese co-twin's fat. In addition, novel pathway analyses of the adipose tissue transcription profiles exposed significant down-regulation of mitochondrial branched-chain amino acid (BCAA) catabolism (p < 0.0001). In line with this finding, serum levels of insulin secretion-enhancing BCAAs were increased in obese male co-twins (9% increase, p = 0.025). Lending clinical relevance to the findings, in both sexes the observed aberrations in mitochondrial amino acid metabolism pathways in fat correlated closely with liver fat accumulation, insulin resistance, and hyperinsulinemia, early aberrations of acquired obesity in these healthy young adults. CONCLUSIONS Our findings emphasize a substantial role of mitochondrial energy- and amino acid metabolism in obesity and development of insulin resistance.
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Affiliation(s)
- Kirsi H Pietiläinen
- Obesity Research Unit, Department of Psychiatry, Helsinki University Central Hospital, Helsinki, Finland
- Department of Medicine, Division of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
- Finnish Twin Cohort Study, Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Jussi Naukkarinen
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
- Department of Medical Genetics and Research Program of Molecular Medicine, University of Helsinki, Finland
| | - Aila Rissanen
- Obesity Research Unit, Department of Psychiatry, Helsinki University Central Hospital, Helsinki, Finland
| | - Juha Saharinen
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
- Department of Medical Genetics and Research Program of Molecular Medicine, University of Helsinki, Finland
| | - Pekka Ellonen
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
- Department of Medical Genetics and Research Program of Molecular Medicine, University of Helsinki, Finland
| | - Heli Keränen
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
- Department of Medical Genetics and Research Program of Molecular Medicine, University of Helsinki, Finland
| | - Anu Suomalainen
- Research Program of Molecular Neurology and Department of Neurology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Alexandra Götz
- Research Program of Molecular Neurology and Department of Neurology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Tapani Suortti
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Hannele Yki-Järvinen
- Department of Medicine, Division of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
| | - Matej Orešič
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Jaakko Kaprio
- Finnish Twin Cohort Study, Department of Public Health, University of Helsinki, Helsinki, Finland
- Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland
| | - Leena Peltonen
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
- Department of Medical Genetics and Research Program of Molecular Medicine, University of Helsinki, Finland
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
- Broad Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * To whom correspondence should be addressed. E-mail:
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Guan L, Song K, Pysz MA, Curry KJ, Hizli AA, Danielpour D, Black AR, Black JD. Protein kinase C-mediated down-regulation of cyclin D1 involves activation of the translational repressor 4E-BP1 via a phosphoinositide 3-kinase/Akt-independent, protein phosphatase 2A-dependent mechanism in intestinal epithelial cells. J Biol Chem 2007; 282:14213-25. [PMID: 17360714 DOI: 10.1074/jbc.m610513200] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We reported previously that protein kinase Calpha (PKCalpha), a negative regulator of cell growth in the intestinal epithelium, inhibits cyclin D1 translation by inducing hypophosphorylation/activation of the translational repressor 4E-BP1. The current study explores the molecular mechanisms underlying PKC/PKCalpha-induced activation of 4E-BP1 in IEC-18 nontransformed rat ileal crypt cells. PKC signaling is shown to promote dephosphorylation of Thr(45) and Ser(64) on 4E-BP1, residues directly involved in its association with eIF4E. Consistent with the known role of the phosphoinositide 3-kinase (PI3K)/Akt/mTOR pathway in regulation of 4E-BP1, PKC signaling transiently inhibited PI3K activity and Akt phosphorylation in IEC-18 cells. However, PKC/PKCalpha-induced activation of 4E-BP1 was not prevented by constitutively active mutants of PI3K or Akt, indicating that blockade of PI3K/Akt signaling is not the primary effector of 4E-BP1 activation. This idea is supported by the fact that PKC activation did not alter S6 kinase activity in these cells. Further analysis indicated that PKC-mediated 4E-BP1 hypophosphorylation is dependent on the activity of protein phosphatase 2A (PP2A). PKC signaling induced an approximately 2-fold increase in PP2A activity, and phosphatase inhibition blocked the effects of PKC agonists on 4E-BP1 phosphorylation and cyclin D1 expression. H(2)O(2) and ceramide, two naturally occurring PKCalpha agonists that promote growth arrest in intestinal cells, activate 4E-BP1 in PKC/PKCalpha-dependent manner, supporting the physiological significance of the findings. Together, our studies indicate that activation of PP2A is an important mechanism underlying PKC/PKCalpha-induced inhibition of cap-dependent translation and growth suppression in intestinal epithelial cells.
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Affiliation(s)
- Lingjie Guan
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
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Pietiläinen KH, Sysi-Aho M, Rissanen A, Seppänen-Laakso T, Yki-Järvinen H, Kaprio J, Orešič M. Acquired obesity is associated with changes in the serum lipidomic profile independent of genetic effects--a monozygotic twin study. PLoS One 2007; 2:e218. [PMID: 17299598 PMCID: PMC1789242 DOI: 10.1371/journal.pone.0000218] [Citation(s) in RCA: 323] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Accepted: 01/26/2007] [Indexed: 11/19/2022] Open
Abstract
Both genetic and environmental factors are involved in the etiology of obesity and the associated lipid disturbances. We determined whether acquired obesity is associated with changes in global serum lipid profiles independent of genetic factors in young adult monozygotic (MZ) twins. 14 healthy MZ pairs discordant for obesity (10 to 25 kg weight difference) and ten weight concordant control pairs aged 24-27 years were identified from a large population-based study. Insulin sensitivity was assessed by the euglycemic clamp technique, and body composition by DEXA (% body fat) and by MRI (subcutaneous and intra-abdominal fat). Global characterization of lipid molecular species in serum was performed by a lipidomics strategy using liquid chromatography coupled to mass spectrometry. Obesity, independent of genetic influences, was primarily related to increases in lysophosphatidylcholines, lipids found in proinflammatory and proatherogenic conditions and to decreases in ether phospholipids, which are known to have antioxidant properties. These lipid changes were associated with insulin resistance, a pathogonomic characteristic of acquired obesity in these young adult twins. Our results show that obesity, already in its early stages and independent of genetic influences, is associated with deleterious alterations in the lipid metabolism known to facilitate atherogenesis, inflammation and insulin resistance.
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Affiliation(s)
- Kirsi H. Pietiläinen
- Obesity Research Unit, Department of Psychiatry, Helsinki University Central Hospital, Helsinki, Finland
- Department of Medicine, Division of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
- Finnish Twin Cohort Study, Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Marko Sysi-Aho
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Aila Rissanen
- Obesity Research Unit, Department of Psychiatry, Helsinki University Central Hospital, Helsinki, Finland
| | | | - Hannele Yki-Järvinen
- Department of Medicine, Division of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
| | - Jaakko Kaprio
- Finnish Twin Cohort Study, Department of Public Health, University of Helsinki, Helsinki, Finland
- Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland
| | - Matej Orešič
- VTT Technical Research Centre of Finland, Espoo, Finland
- * To whom correspondence should be addressed. E-mail:
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Takenaka T, Kanno Y, Ohno Y, Suzuki H. Key role of insulin resistance in vascular injury among hemodialysis patients. Metabolism 2007; 56:153-9. [PMID: 17224326 DOI: 10.1016/j.metabol.2006.08.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Accepted: 08/23/2006] [Indexed: 12/16/2022]
Abstract
Insulin resistance prevails not only among diabetic patients but also among hypertensive and obese patients. The relationship between insulin resistance and cardiovascular diseases was investigated in hemodialysis (HD) patients. Eighty-one maintenance HD patients were enrolled. The homeostasis model assessment of insulin resistance (HOMA-IR) method was used to assess insulin resistance. The relationship of HOMA-IR with cardiovascular and all-cause events was assessed. Compared with nondiabetic patients (n = 55), diabetic patients (n = 26) showed higher HOMA-IR (2.5 +/- 0.3 vs 1.4 +/- 0.2, P < .05), lower ankle-brachial pressure index (ABI, 0.85 +/- 0.09 vs 1.12 +/- 0.02, P < .01), and shorter HD duration (3 +/- 1 vs 9 +/- 1 years, P < .01), although their body mass index was similar (22.3 +/- 0.5 vs 21.5 +/- 0.4 kg/m(2)). Nondiabetic patients taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (n = 36) had lower HOMA-IR (1.2 +/- 0.2 vs 1.8 +/- 0.4, P < .05) and higher ABI (1.18 +/- 0.02 vs 1.02 +/- 0.05, P < .01) than those without (n = 17). Cardiovascular events were less common in HD patients with normal HOMA-IR (P < .05) or ABI (P < .01). Our data indicate that 69% of diabetic and 27% of nondiabetic patients have HOMA-IR greater than 1.6, implying reduced insulin sensitivity in HD patients. The present results provide evidence that angiotensin inhibition improves insulin resistance, possibly preventing vascular injury in HD patients. Finally, our findings suggest that insulin resistance is prognostic of cardiovascular events in HD patients.
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Mookerjee Basu J, Mookerjee A, Sen P, Bhaumik S, Sen P, Banerjee S, Naskar K, Choudhuri SK, Saha B, Raha S, Roy S. Sodium antimony gluconate induces generation of reactive oxygen species and nitric oxide via phosphoinositide 3-kinase and mitogen-activated protein kinase activation in Leishmania donovani-infected macrophages. Antimicrob Agents Chemother 2006; 50:1788-97. [PMID: 16641451 PMCID: PMC1472228 DOI: 10.1128/aac.50.5.1788-1797.2006] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Pentavalent antimony complexes, such as sodium stibogluconate and sodium antimony gluconate (SAG), are still the first choice for chemotherapy against various forms of leishmaniasis, including visceral leishmaniasis, or kala-azar. Although the requirement of a somewhat functional immune system for the antileishmanial action of antimony was reported previously, the cellular and molecular mechanism of action of SAG was not clear. Herein, we show that SAG induces extracellular signal-regulated kinase 1 (ERK-1) and ERK-2 phosphorylation through phosphoinositide 3-kinase (PI3K), protein kinase C, and Ras activation and p38 mitogen-activated protein kinase (MAPK) phosphorylation through PI3K and Akt activation. ERK-1 and ERK-2 activation results in an increase in the production of reactive oxygen species (ROS) 3 to 6 h after SAG treatment, while p38 MAPK activation and subsequent tumor necrosis factor alpha release result in the production of nitric oxide (NO) 24 h after SAG treatment. Thus, this study has provided the first evidence that SAG treatment induces activation of some important components of the intracellular signaling pathway, which results in an early wave of ROS-dependent parasite killing and a stronger late wave of NO-dependent parasite killing. This opens up the possibility of this metalloid chelate being used in the treatment of various diseases either alone or in combination with other drugs and vaccines.
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Affiliation(s)
- Jayati Mookerjee Basu
- Department of Immunology, Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, India.
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Labonté ED, Kirby RJ, Schildmeyer NM, Cannon AM, Huggins KW, Hui DY. Group 1B phospholipase A2-mediated lysophospholipid absorption directly contributes to postprandial hyperglycemia. Diabetes 2006; 55:935-41. [PMID: 16567514 PMCID: PMC2048981 DOI: 10.2337/diabetes.55.04.06.db05-1286] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Postprandial hyperglycemia is an early indicator of abnormality in glucose metabolism leading to type 2 diabetes. However, mechanisms that contribute to postprandial hyperglycemia have not been identified. This study showed that mice with targeted inactivation of the group 1B phospholipase A2 (Pla2g1b) gene displayed lower postprandial glycemia than that observed in wild-type mice after being fed a glucose-rich meal. The difference was caused by enhanced postprandial glucose uptake by the liver, heart, and muscle tissues as well as altered postprandial hepatic glucose metabolism in the Pla2g1b-/- mice. These differences were attributed to a fivefold decrease in the amount of dietary phospholipids absorbed as lysophospholipids in Pla2g1b-/- mice compared with that observed in Pla2g1b+/+ mice. Elevating plasma lysophospholipid levels in Pla2g1b-/- mice via intraperitoneal injection resulted in glucose intolerance similar to that exhibited by Pla2g1b+/+ mice. Studies with cultured hepatoma cells revealed that lysophospholipids dose-dependently suppressed insulin-stimulated glycogen synthesis. These results demonstrated that reduction of lysophospholipid absorption enhances insulin-mediated glucose metabolism and is protective against postprandial hyperglycemia.
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Affiliation(s)
- Eric D Labonté
- Department of Pathology, Genome Research Institute, University of Cincinnati, 2120 E. Galbraith Rd., Cincinnati, OH 45237-0507, USA
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Yan S, Chai H, Wang H, Yang H, Nan B, Yao Q, Chen C. Effects of lysophosphatidylcholine on monolayer cell permeability of human coronary artery endothelial cells. Surgery 2005; 138:464-73. [PMID: 16213900 DOI: 10.1016/j.surg.2005.06.027] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Revised: 06/22/2005] [Accepted: 06/25/2005] [Indexed: 11/25/2022]
Abstract
BACKGROUND Lysophosphatidylcholine (LysoPC) is a product of phosphatidylcholine hydrolysis by phospholipase A2, which is associated with atherosclerosis. However, the underlying molecular mechanisms are still unclear. The purpose of this study was to determine the effects of LysoPC on monolayer permeability of human coronary artery endothelial cells (HCAECs). METHODS HCAECs were cultured with LysoPC in a dose- and time-dependent manner. Monolayer permeability was studied by using a transwell system with a Texas-Red-labeled dextran tracer. The messenger RNA and protein levels of endothelial tight junction proteins were determined with the use of real-time reverse transcriptase-polymerase chain reaction and Western blot analysis, respectively. Superoxide anion levels were determined with the use of fluorescent dye dihydroethidium-based flow cytometry analysis. Activation of mitogen-activated protein kinases was determined by performing Bio-Plex immunoassay. RESULTS LysoPC (30 micromol/L) increased monolayer permeability by 53% and decreased the messenger RNA levels of zonula occludens-1, occludin, claudin-1, and junctional adhesion molecule by 44%, 53%, 50%, and 52%, respectively, compared with controls (P < .05). Western blot analysis showed reduced protein levels of these tight junction molecules. LysoPC (15 and 30 micromol/L) also increased superoxide anion production by 54% and 58%, respectively, compared with controls (P < .05). Antioxidant seleno-L-methionine (20 and 30 micromol/L) inhibited LysoPC (30 micromol/L)-induced permeability by 42% and 68%, respectively (P < .05). Furthermore, LysoPC (30 micromol/L) activated c-Jun N-terminal kinase and p38 phosphorylation, but not extracellular signal-related kinase 1/2, within 5 to 10 minutes. CONCLUSIONS LysoPC increases monolayer permeability and reduces the expression of tight junction molecules in HCAECs through oxidative stress and activation of c-Jun N-terminal kinase and p38 mitogen-activated protein kinase. The antioxidant can effectively block LysoPC-induced endothelial permeability.
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Affiliation(s)
- Shaoyu Yan
- Molecular Surgeon Research Center, Division of Vascular Surgery and Endovascular Therapy, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA
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37
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Frank GD, Eguchi S, Motley ED. The role of reactive oxygen species in insulin signaling in the vasculature. Antioxid Redox Signal 2005; 7:1053-61. [PMID: 15998260 DOI: 10.1089/ars.2005.7.1053] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Although there is an abundance of evidence suggesting that insulin resistance plays a significant role in the vasculature, the precise mechanistic role involved still remains unclear. In this review, we discuss the current background of insulin resistance in the context of insulin signaling and action in the vasculature. Also, studies suggest that insulin resistance, diabetes, and cardiovascular disease all share a common involvement with oxidative stress. Recently, we reported that lysophosphatidylcholine, a major bioactive product of oxidized low-density lipoprotein, and angiotensin II, a vasoactive hormone and a potent inducer of reactive oxygen species (ROS), negatively regulate insulin signaling in vascular smooth muscle cells (VSMCs). In endothelial cells, insulin stimulates the release of nitric oxide, which results in VSMC relaxation and inhibition of atherosclerosis. Other data suggest that angiotensin II inhibits the vasodilator effects of insulin through insulin receptor substrate-1 phosphorylation at Ser312 and Ser616. Moreover, ROS impair insulin-induced vasorelaxation by neutralizing nitric oxide to form peroxynitrite. Thus, evidence is growing to enable us to better understand mechanistically the relationship between insulin/insulin resistance and ROS in the vasculature, and the impact they have on cardiovascular disease.
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Affiliation(s)
- Gerald D Frank
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
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38
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Abstract
This review is focused on the interplay between two major factors affecting the vascular tree in diabetes, insulin resistance, and hyperglycemia. The implications for vascular function, structure, and the interaction between vascular cells and other tissues by which they are affected under these conditions are reviewed.
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Affiliation(s)
- Naftali Stern
- Institute of Endocrinology, Metabolism, and Hypertension, Tel Aviv-Sourasky Medical Center, 6 Weizman Street, Tel Aviv 64239, Israel.
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Wang J, Zhang Y, Wang H, Han H, Nattel S, Yang B, Wang Z. Potential mechanisms for the enhancement of HERG K+ channel function by phospholipid metabolites. Br J Pharmacol 2004; 141:586-99. [PMID: 14744814 PMCID: PMC1574230 DOI: 10.1038/sj.bjp.0705646] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Phospholipid metabolites lysophospholipids cause extracellular K(+) accumulation and action potential shortening with increased risk of arrhythmias during myocardial ischemia. Here we studied effects of several lysophospholipids with different lengths of hydrocarbon chains and charged headgroups on HERG K(+) currents (I(HERG)) expressed in HEK293 cells and the potential mechanisms using whole-cell patch-clamp techniques. 2. Only the lipids with 16 hydrocarbons such as 1-palmitoyl-lysophosphatidylcholine (LPC-16) and 1-palmitoyl-lysophosphatidylglycerol (LPG-16) were found to produce significant enhancement of I(HERG) and negative shifts of HERG activation, although the voltage dependence of the effects was different between LPC-16 and LPG-16 which have differently charged headgroups. The lipid with 18 hydrocarbons modestly increased I(HERG). The lipids with 6 or 24 hydrocarbons had no effect or slightly decreased I(HERG). 3. Inhibition or activation of protein kinase C did not alter the effects of LPC-16 and LPG-16. Participation of phosphatidylinositol-4,5-bisphosphate in I(HERG) enhancement by LPC-16/LPG-16 was also excluded. 4. Vitamin E augmented the effects of LPC-16/LPG-16 whereas xanthine/xanthine oxidase reduced I(HERG): indicating that LPC-16/LPG-16 produced dual effects on I(HERG): direct enhancement of I(HERG) and indirect suppression via production of superoxide anion. 5. We conclude that enhancement of HERG function by lysophospholipids is specific to the lipids with 16-hydrocarbon chain structure and the pattern of voltage dependence is determined by the polar headgroups. The increase in I(HERG) is best described by direct interactions between lipid molecules and HERG proteins, which is consistent with lack of effects via membrane destabilization or modulation by intracellular signaling pathways.
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Affiliation(s)
- Jingxiong Wang
- Research Center, Montreal Heart Institute, Montreal, Canada PQ H1T 1C8
- Department of Medicine, University of Montreal, Montreal, Canada, PQ H3C 3J7
| | - Yiqiang Zhang
- Research Center, Montreal Heart Institute, Montreal, Canada PQ H1T 1C8
- Department of Medicine, University of Montreal, Montreal, Canada, PQ H3C 3J7
| | - Huizhen Wang
- Research Center, Montreal Heart Institute, Montreal, Canada PQ H1T 1C8
| | - Hong Han
- Research Center, Montreal Heart Institute, Montreal, Canada PQ H1T 1C8
| | - Stanley Nattel
- Research Center, Montreal Heart Institute, Montreal, Canada PQ H1T 1C8
- Department of Medicine, University of Montreal, Montreal, Canada, PQ H3C 3J7
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Canada PQ H3G 1Y6
| | - Baofeng Yang
- Department of Pharmacology, Harbin Medical University, Harbin, HeilongJiang, PR China
| | - Zhiguo Wang
- Research Center, Montreal Heart Institute, Montreal, Canada PQ H1T 1C8
- Department of Medicine, University of Montreal, Montreal, Canada, PQ H3C 3J7
- Author for correspondence:
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40
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Birner R, Daum G. Biogenesis and cellular dynamics of aminoglycerophospholipids. INTERNATIONAL REVIEW OF CYTOLOGY 2003; 225:273-323. [PMID: 12696595 DOI: 10.1016/s0074-7696(05)25007-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Aminoglycerophospholipids phosphatidylserine (PtdSer), phosphatidylethanolamine (PtdEtn), and phosphatidylcholine (PtdCho) comprise about 80% of total cellular phospholipids in most cell types. While the major function of PtdCho in eukaryotes and PtdEtn in prokaryotes is that of bulk membrane lipids, PtdSer is a minor component and appears to play a more specialized role in the plasma membrane of eukaryotes, e.g., in cell recognition processes. All three aminoglycerophospholipid classes are essential in mammals, whereas prokaryotes and lower eukaryotes such as yeast appear to be more flexible regarding their aminoglycerophospholipid requirement. Since different subcellular compartments of eukaryotes, namely the endoplasmic reticulum and mitochondria, contribute to the biosynthetic sequence of aminoglycerophospholipid formation, intracellular transport, sorting, and specific function of these lipids in different organelles are of special interest.
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Affiliation(s)
- Ruth Birner
- Institut für Biochemie, Technische Universität Graz, Petersgasse 12/2, A-8010 Graz, Austria
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Tanaka Y, Gavrielides MV, Mitsuuchi Y, Fujii T, Kazanietz MG. Protein kinase C promotes apoptosis in LNCaP prostate cancer cells through activation of p38 MAPK and inhibition of the Akt survival pathway. J Biol Chem 2003; 278:33753-62. [PMID: 12824193 DOI: 10.1074/jbc.m303313200] [Citation(s) in RCA: 203] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Activation of protein kinase C (PKC) by phorbol esters or diacylglycerol mimetics induces apoptosis in androgen-dependent prostate cancer cells, an effect that involves both the activation of the classic PKC alpha and the novel PKC delta isozymes (Fujii, T., García-Bermejo, M. L., Bernabó, J. L., Caamaño, J., Ohba, M., Kuroki, T., Li, L., Yuspa, S. H., and Kazanietz, M. G. (2000) J. Biol. Chem. 275, 7574-7582 and Garcia-Bermejo, M. L., Leskow, F. C., Fujii, T., Wang, Q., Blumberg, P. M., Ohba, M., Kuroki, T., Han, K. C., Lee, J., Marquez, V. E., and Kazanietz, M. G. (2002) J. Biol. Chem. 277, 645-655). In the present study we explored the signaling events involved in this PKC-mediated effect, using the androgen-dependent LNCaP cell line as a model. Stimulation of PKC by phorbol 12-myristate 13-acetate (PMA) leads to the activation of ERK1/2, p38 MAPK, and JNK in LNCaP cells. Here we present evidence that p38 MAPK, but not JNK, mediates PKC-induced apoptosis. Because LNCaP cells have hyperactivated Akt function due to PTEN inactivation, we examined whether this survival pathway could be affected by PKC activation. Interestingly, activation of PKC leads to a rapid and reversible dephosphorylation of Akt, an effect that was prevented by the pan-PKC inhibitor GF109302X and the cPKC inhibitor Gö6976. In addition, the diacylglycerol mimetic agent HK654, which selectively stimulates PKC alpha in LNCaP cells, also induced the dephosphorylation of Akt in LNCaP cells. Inactivation of Akt function by PKC does not involve the inhibition of PI3K, and it is prevented by okadaic acid, suggesting the involvement of a phosphatase 2A in PMA-induced Akt dephosphorylation. Finally, we show that, when an activated form of Akt is delivered into LNCaP cells by either transient transfection or adenoviral infection, the apoptotic effect of PMA is significantly reduced. Our results highlight a complex array of signaling pathways regulated by PKC isozymes in LNCaP prostate cancer cells and suggest that both p38 MAPK and Akt play critical roles as downstream effectors of PKC isozymes in this cellular model.
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Affiliation(s)
- Yuichi Tanaka
- Center for Experimental Therapeutics and Department of Pharmacology, Philadelphia, Pennsylvania 19104-6160, USA
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42
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Gardner CD, Eguchi S, Reynolds CM, Eguchi K, Frank GD, Motley ED. Hydrogen peroxide inhibits insulin signaling in vascular smooth muscle cells. Exp Biol Med (Maywood) 2003; 228:836-42. [PMID: 12876303 DOI: 10.1177/15353702-0322807-09] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Both insulin resistance and reactive oxygen species (ROS) have been reported to play essential pathophysiological roles in cardiovascular diseases, such as hypertension and atherosclerosis. However, the mechanistic link between ROS, such as H2O2 and insulin resistance in the vasculature, remains undetermined. Akt, a Ser/Thr kinase, mediates various biological responses induced by insulin. In this study, we examined the effects of H2O2 on Akt activation in the insulin-signaling pathway in vascular smooth muscle cells (VSMCs). In VSMCs, insulin stimulates Akt phosphorylation at Ser473. Pretreatment with H2O2 concentration- and time-dependently inhibited insulin-induced Akt phosphorylation with significant inhibition observed at 50 microM for 10 min. A ROS inducer, diamide, also inhibited insulin-induced Akt phosphorylation. In addition, H2O2 inhibited insulin receptor binding partially and inhibited insulin receptor autophosphorylation almost completely. However, pretreatment with a protein kinase C inhibitor, GF109203X (2 microM), for 30 min did not block the inhibitory effects of H2O2 on insulin-induced Akt phosphorylation, suggesting that protein kinase C is not involved in the inhibition by H2O2. We conclude that ROS inhibit a critical insulin signal transduction component required for Akt activation in VSMCs, suggesting potential cellular mechanisms of insulin resistance, which would require verification in vivo.
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MESH Headings
- Animals
- Diamide/pharmacology
- Drug Interactions
- Enzyme Activation/drug effects
- Enzyme Inhibitors/pharmacology
- Hydrogen Peroxide/pharmacology
- Indoles/pharmacology
- Insulin/metabolism
- Insulin/pharmacology
- Maleimides/pharmacology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Phosphorylation
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/metabolism
- Protein Serine-Threonine Kinases
- Proto-Oncogene Proteins/antagonists & inhibitors
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-akt
- Rats
- Rats, Sprague-Dawley
- Receptor, Insulin/metabolism
- Serine/metabolism
- Signal Transduction/drug effects
- Time Factors
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Affiliation(s)
- Carla D Gardner
- Department of Anatomy and Physiology, Meharry Medical College, Nashville, Tennessee 37208, USA
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Thors B, Halldórsson H, Clarke GD, Thorgeirsson G. Inhibition of Akt phosphorylation by thrombin, histamine and lysophosphatidylcholine in endothelial cells. Differential role of protein kinase C. Atherosclerosis 2003; 168:245-53. [PMID: 12801607 DOI: 10.1016/s0021-9150(03)00127-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The protein kinase Akt is involved in embryonic vascular development and neoangiogenesis as well as in several endothelial cell functions, including activation of endothelial NO-synthase (eNOS) and promotion of endothelial cell survival. We have examined the effects of G-protein activators thrombin and histamine as well as lysophosphatidylcholine (LPC) on Akt phosphorylation in cultured human umbilical vein endothelial cells (HUVEC). Akt phosphorylation was analyzed with the phosphospecific Akt (Ser473) antibody by Western blotting. While epidermal growth factor (EGF) was a potent stimulator of Akt phosphorylation histamine, thrombin and LPC blocked its activation when used in cotreatment with EGF. Following inhibition or downregulation of protein kinase C (PKC), the inhibitory effect of both histamine and thrombin on the endothelial response to EGF was prevented. Furthermore, stimulation of PKC, using short-term 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment, markedly inhibited the stimulatory effects of EGF on Akt phosphorylation. Rottlerin, an inhibitor of the PKCdelta, but not Gö6976, which is an inhibitor of alpha, beta, gamma and isoforms, reversed the inhibitory effects of histamine. Conversely, inhibition or downregulation of PKC did not prevent the inhibitory effect of LPC. Akt phosphorylation was also increased by sphingosine 1-phosphate (S1P) treatment and this activity was influenced by the various cotreatments in the same way as the activation by EGF. Overall, this study demonstrated that the G-protein activators thrombin and histamine inhibited both EGF- and S1P-mediated Akt phosphorylation in HUVEC by activation of PKCdelta, while the inhibitory effects of LPC were independent of PKCdelta.
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Affiliation(s)
- Brynhildur Thors
- Institute of Pharmacy, Pharmacology and Toxicology, University of Iceland, P.O. Box 8216, 128 Reykjavik, Iceland
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Saito S, Frank GD, Mifune M, Ohba M, Utsunomiya H, Motley ED, Inagami T, Eguchi S. Ligand-independent trans-activation of the platelet-derived growth factor receptor by reactive oxygen species requires protein kinase C-delta and c-Src. J Biol Chem 2002; 277:44695-700. [PMID: 12226102 DOI: 10.1074/jbc.m208332200] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Reactive oxygen species are involved in the mitogenic signal transduction cascades initiated by several growth factors and play a critical role in mediating cardiovascular diseases. Interestingly, H(2)O(2) induces tyrosine phosphorylation and trans-activation of the platelet-derived growth factor receptor and the epidermal growth factor receptor in many cell lines including vascular smooth muscle cells. To investigate the molecular mechanism by which reactive oxygen species contribute to vascular diseases, we have examined a signal transduction cascade involved in H(2)O(2)-induced platelet-derived growth factor receptor activation in vascular smooth muscle cells. We found that H(2)O(2) induced a ligand-independent phosphorylation of the platelet-derived growth factor-beta receptor at Tyr(1021), a phospholipase C-gamma binding site, involving the requirement of protein kinase C-delta and c-Src that is distinct from a ligand-dependent autophosphorylation. Also, H(2)O(2) induced the association of protein kinase C-delta with the platelet-derived growth factor-beta receptor and c-Src in vascular smooth muscle cells. These findings will provide new mechanistic insights by which enhanced reactive oxygen species production in vascular smooth muscle cells induces unique alleys of signal transduction distinct from those induced by endogenous ligands leading to an abnormal vascular remodeling process.
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Affiliation(s)
- Shuichi Saito
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA
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