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Magnuson MA, Osipovich AB. Ca 2+ signaling and metabolic stress-induced pancreatic β-cell failure. Front Endocrinol (Lausanne) 2024; 15:1412411. [PMID: 39015185 PMCID: PMC11250477 DOI: 10.3389/fendo.2024.1412411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 06/10/2024] [Indexed: 07/18/2024] Open
Abstract
Early in the development of Type 2 diabetes (T2D), metabolic stress brought on by insulin resistance and nutrient overload causes β-cell hyperstimulation. Herein we summarize recent studies that have explored the premise that an increase in the intracellular Ca2+ concentration ([Ca2+]i), brought on by persistent metabolic stimulation of β-cells, causes β-cell dysfunction and failure by adversely affecting β-cell function, structure, and identity. This mini-review builds on several recent reviews that also describe how excess [Ca2+]i impairs β-cell function.
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Affiliation(s)
- Mark A. Magnuson
- Department of Molecular Physiology and Biophysics and Center for Stem Cell Biology, Vanderbilt University, Nashville, TN, United States
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Wang J, Wen S, Chen M, Xie J, Lou X, Zhao H, Chen Y, Zhao M, Shi G. Regulation of endocrine cell alternative splicing revealed by single-cell RNA sequencing in type 2 diabetes pathogenesis. Commun Biol 2024; 7:778. [PMID: 38937540 PMCID: PMC11211498 DOI: 10.1038/s42003-024-06475-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 06/19/2024] [Indexed: 06/29/2024] Open
Abstract
The prevalent RNA alternative splicing (AS) contributes to molecular diversity, which has been demonstrated in cellular function regulation and disease pathogenesis. However, the contribution of AS in pancreatic islets during diabetes progression remains unclear. Here, we reanalyze the full-length single-cell RNA sequencing data from the deposited database to investigate AS regulation across human pancreatic endocrine cell types in non-diabetic (ND) and type 2 diabetic (T2D) individuals. Our analysis demonstrates the significant association between transcriptomic AS profiles and cell-type-specificity, which could be applied to distinguish the clustering of major endocrine cell types. Moreover, AS profiles are enabled to clearly define the mature subset of β-cells in healthy controls, which is completely lost in T2D. Further analysis reveals that RNA-binding proteins (RBPs), heterogeneous nuclear ribonucleoproteins (hnRNPs) and FXR1 family proteins are predicted to induce the functional impairment of β-cells through regulating AS profiles. Finally, trajectory analysis of endocrine cells suggests the β-cell identity shift through dedifferentiation and transdifferentiation of β-cells during the progression of T2D. Together, our study provides a mechanism for regulating β-cell functions and suggests the significant contribution of AS program during diabetes pathogenesis.
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Affiliation(s)
- Jin Wang
- Department of Endocrinology & Metabolism, Medical Center for Comprehensive Weight Control, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
| | - Shiyi Wen
- Department of Endocrinology & Metabolism, Medical Center for Comprehensive Weight Control, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Minqi Chen
- Key Laboratory of Stem Cells and Tissue Engineering, Zhongshan School of Medicine, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China
| | - Jiayi Xie
- Key Laboratory of Stem Cells and Tissue Engineering, Zhongshan School of Medicine, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China
| | - Xinhua Lou
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Haihan Zhao
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yanming Chen
- Department of Endocrinology & Metabolism, Medical Center for Comprehensive Weight Control, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Provincial Key Laboratory of Diabetology & Guangzhou Municipal Key Laboratory of Mechanistic and Translational Obesity Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Meng Zhao
- Key Laboratory of Stem Cells and Tissue Engineering, Zhongshan School of Medicine, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.
| | - Guojun Shi
- Department of Endocrinology & Metabolism, Medical Center for Comprehensive Weight Control, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
- Guangdong Provincial Key Laboratory of Diabetology & Guangzhou Municipal Key Laboratory of Mechanistic and Translational Obesity Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
- State Key Laboratory of Oncology in Southern China, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China.
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Han G, Yu J, He J, Zheng P, Mao X, Yu B. Subtherapeutic Kitasamycin Promoted Fat Accumulation in the Longissimus Dorsi Muscle in Growing-Finishing Pigs. Animals (Basel) 2024; 14:1057. [PMID: 38612296 PMCID: PMC11010921 DOI: 10.3390/ani14071057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 04/14/2024] Open
Abstract
Kitasamycin (KM), a broad-spectrum macrolide antibiotic, has implications for growth performance and residue in animals and humans. This study aimed to explore the effects of different KM doses on intramuscular fat accumulation, cecal microflora, and short-chain fatty acids (SCFAs) using a growing-finishing pig model. Forty-two pigs were divided into three groups: control, subtherapeutic KM (50 mg/kg, KM50), and therapeutic KM (200 mg/kg, KM200) diets over 8 weeks. KM50 led to increased back fat thickness, fat content in the longissimus dorsi muscle (LM), and elevated plasma total cholesterol (TC) levels (p < 0.05), supported by upregulated lipid synthesis gene expression (Acc1, Fas, Scd1) (p < 0.05) in the LM. KM50 altered cecal microflora, reducing Lactobacillus spp. and Bifidobacterium spp. abundance, while increasing SCFA concentrations (acetic acid, propionic acid, total SCFAs) (p < 0.05). KM200 had minimal effects on intestinal weight and density, with increased apparent digestibility of nutrients. These findings highlight the dose-dependent impact of KM on intramuscular fat deposition. Subtherapeutic KM induced ectopic fat deposition, emphasizing potential risks in disease treatment for humans and animals.
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Affiliation(s)
| | | | | | | | | | - Bing Yu
- Key Laboratory of Animal Disease-Resistant Nutrition and Feed of China Ministry of Agriculture and Rural Affairs, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China; (G.H.); (J.Y.); (J.H.); (P.Z.)
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Zaczek A, Lewiński A, Karbownik-Lewińska M, Lehoczki A, Gesing A. Impact of visceral adipose tissue on longevity and metabolic health: a comparative study of gene expression in perirenal and epididymal fat of Ames dwarf mice. GeroScience 2024:10.1007/s11357-024-01131-1. [PMID: 38517641 DOI: 10.1007/s11357-024-01131-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 03/09/2024] [Indexed: 03/24/2024] Open
Abstract
Emerging research underscores the pivotal role of adipose tissue in regulating systemic aging processes, particularly when viewed through the lens of the endocrine hypotheses of aging. This study delves into the unique adipose characteristics in an important animal model of aging - the long-lived Ames dwarf (df/df) mice. Characterized by a Prop1df gene mutation, these mice exhibit a deficiency in growth hormone (GH), prolactin, and TSH, alongside extremely low circulating IGF-1 levels. Intriguingly, while surgical removal of visceral fat (VFR) enhances insulin sensitivity in normal mice, it paradoxically increases insulin resistance in Ames dwarfs. This suggests an altered profile of factors produced in visceral fat in the absence of GH, indicating a unique interplay between adipose tissue function and hormonal influences in these models. Our aim was to analyze the gene expression related to lipid and glucose metabolism, insulin pathways, inflammation, thermoregulation, mitochondrial biogenesis, and epigenetic regulation in the visceral (perirenal and epididymal) adipose tissue of Ames dwarf and normal mice. Our findings reveal an upregulation in the expression of key genes such as Lpl, Adrβ3, Rstn, Foxo1, Foxo3a, Irs1, Cfd, Aldh2, Il6, Tnfα, Pgc1α, Ucp2, and Ezh2 in perirenal and Akt1, Foxo3a, PI3k, Ir, Acly, Il6, Ring1a, and Ring 1b in epididymal fat in df/df mice. These results suggest that the longevity phenotype in Ames dwarfs, which is determined by peripubertal GH/IGF-1 levels, may also involve epigenetic reprogramming of adipose tissue influenced by hormonal changes. The increased expression of genes involved in metabolic regulation, tumor suppression, mitochondrial biogenesis, and insulin pathways in Ames dwarf mice highlights potentially beneficial aspects of this model, opening new avenues for understanding the molecular underpinnings of longevity and aging.
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Affiliation(s)
- Agnieszka Zaczek
- Department of Endocrinology of Ageing, Medical University of Lodz, Lodz, Poland
| | - Andrzej Lewiński
- Department of Paediatric Endocrinology, Medical University of Lodz, Lodz, Poland
- Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland
| | - Małgorzata Karbownik-Lewińska
- Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland
| | - Andrea Lehoczki
- Department of Public Health, Semmelweis University, Budapest, Hungary
- Doctoral School, Health Sciences Program, Semmelweis University, Budapest, Hungary
- Department of Haematology and Stem Cell Transplantation, National Institute for Haematology and Infectious Diseases, South Pest Central Hospital, 1097, Budapest, Hungary
| | - Adam Gesing
- Department of Endocrinology of Ageing, Medical University of Lodz, Lodz, Poland.
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Arjunan A, Song J. Pharmacological and physiological roles of adipokines and myokines in metabolic-related dementia. Biomed Pharmacother 2023; 163:114847. [PMID: 37150030 DOI: 10.1016/j.biopha.2023.114847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/27/2023] [Accepted: 05/04/2023] [Indexed: 05/09/2023] Open
Abstract
Dementia is a detrimental neuropathologic condition with considerable physical, mental, social, and financial impact on patients and society. Patients with metabolic syndrome (MetS), a group of diseases that occur in tandem and increase the risk of neurologic diseases, have a higher risk of dementia. The ratio between muscle and adipose tissue is crucial in MetS, as these contain many hormones, including myokines and adipokines, which are involved in crosstalk and local paracrine/autocrine interactions. Evidence suggests that abnormal adipokine and myokine synthesis and release may be implicated in various MetS, such as atherosclerosis, diabetic mellitus (DM), and dyslipidemia, but their precise role is unclear. Here we review the literature on adipokine and myokine involvement in MetS-induced dementia via glucose and insulin homeostasis regulation, neuroinflammation, vascular dysfunction, emotional changes, and cognitive function.
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Affiliation(s)
- Archana Arjunan
- Department of Anatomy, Chonnam National University Medical School, Seoyangro 264, Hwasun 58128, Republic of Korea
| | - Juhyun Song
- Department of Anatomy, Chonnam National University Medical School, Seoyangro 264, Hwasun 58128, Republic of Korea.
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Li Y, Chen Y, Liu Z, Lin B, Deng X, Xiao Q, Chen Z, Ye H, Chen D, Su Y, Li W, Xu W. Downregulation of Kcnq1ot1 attenuates β-cell proliferation and insulin secretion via the miR-15b-5p/Ccnd1 and Ccnd2 axis. Acta Diabetol 2022; 59:885-899. [PMID: 35347427 DOI: 10.1007/s00592-022-01871-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/18/2022] [Indexed: 12/20/2022]
Abstract
AIM To examine the effect of lncRNA Kcnq1ot1 on pancreatic β cells in the development of diabetes. METHODS The expression levels of Kcnq1ot1 were detected in the islets of diabetes mouse models and the serum of patients with type 2 diabetes by qRT-PCR. CCK8, Ki67 staining, immunohistochemical analyses, glucose-stimulated insulin secretion and intraperitoneal glucose tolerance test were performed to detect the effect of Kcnq1ot1 on β-cell proliferation and insulin secretion in vitro and in vivo. The relationship between Kcnq1ot1 and miR-15b-5p was predicted by bioinformatics prediction, which was confirmed by luciferase reporter assay. RESULTS Kcnq1ot1 was more abundant in the pancreas. The expression of Kcnq1ot1 was decreased in the islets of db/db mice and diet-induced obese mice and in the serum of patients with type 2 diabetes. Silencing Kcnq1ot1 inhibited the β-cell proliferation concomitant with a reduction in the levels of Ccnd1 and Ccnd2. Insulin synthesis and secretion were impaired, along with the decreased expression of Ins1, Ins2, and insulin-related transcription factors. Moreover, Kcnq1ot1 knockdown in vivo reduced glucose tolerance and decreased insulin secretion, consistent with the reduction in the relative islet area and Ki67-positive β-cells detected by immunochemistry and immunofluorescence staining, respectively. Mechanistically, Kcnq1ot1 directly targeted miR-15b-5p which regulated β-cell proliferation and insulin secretion through Ccnd1 and Ccnd2. Notably, the suppression of miR-15b-5p attenuated the inhibition of Min6 proliferation and insulin production induced by Kcnq1ot1 knockdown. CONCLUSION Kcnq1ot1 regulated β-cell proliferation and insulin secretion via the miR-15b-5p/Ccnd1 and Ccnd2 axis, which is worthy of further investigation considering its potential in diabetes treatment.
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Affiliation(s)
- Yanli Li
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China
| | - Yalan Chen
- Key Laboratory of Diabetology of Guangdong Province, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, China
| | - Ziyu Liu
- Key Laboratory of Diabetology of Guangdong Province, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, China
| | - Beisi Lin
- Key Laboratory of Diabetology of Guangdong Province, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, China
| | - Xiaoyi Deng
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China
| | - Qiwen Xiao
- Department of Clinical Laboratory, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhishan Chen
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China
| | - Huiyu Ye
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China
| | - Danrui Chen
- Key Laboratory of Diabetology of Guangdong Province, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, China
| | - Yanna Su
- Key Laboratory of Diabetology of Guangdong Province, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, China
| | - Wangen Li
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China.
| | - Wen Xu
- Key Laboratory of Diabetology of Guangdong Province, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, China.
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Feng J, Wang X, Ye X, Ares I, Lopez-Torres B, Martínez M, Martínez-Larrañaga MR, Wang X, Anadón A, Martínez MA. Mitochondria as an important target of metformin: The mechanism of action, toxic and side effects, and new therapeutic applications. Pharmacol Res 2022; 177:106114. [DOI: 10.1016/j.phrs.2022.106114] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/21/2022] [Accepted: 02/01/2022] [Indexed: 12/25/2022]
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Römer A, Rawat D, Linn T, Petry SF. Preparation of fatty acid solutions exerts significant impact on experimental outcomes in cell culture models of lipotoxicity. Biol Methods Protoc 2022; 7:bpab023. [PMID: 35036572 PMCID: PMC8754478 DOI: 10.1093/biomethods/bpab023] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/25/2021] [Accepted: 11/30/2021] [Indexed: 11/14/2022] Open
Abstract
Free fatty acids are essentially involved in the pathogenesis of chronic diseases such as diabetes mellitus, non-alcoholic fatty liver disease, and cardiovascular disease. They promote mitochondrial dysfunction, oxidative stress, respiratory chain uncoupling, and endoplasmic reticulum stress and modulate stress-sensitive pathways. These detrimental biological effects summarized as lipotoxicity mainly depend on fatty acid carbon chain length, degree of unsaturation, concentration, and treatment time. Preparation of fatty acid solutions involves dissolving and complexing. Solvent toxicity and concentration, amount of bovine serum albumin (BSA), and ratio of albumin to fatty acids can vary significantly between equal concentrations, mediating considerable harmful effects and/or interference with certain assays such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Herein, we studied the impact of commonly used solvents ethanol and dimethyl sulfoxide and varying concentrations of BSA directly and in solution with oleic acid on MTT to formazan conversion, adenosine triphosphate level, and insulin content and secretion of murine β-cell line MIN6 employing different treatment duration. Our data show that experimental outcomes and assay readouts can be significantly affected by mere preparation of fatty acid solutions and should thus be carefully considered and described in detail to ensure comparability and distinct evaluation of data.
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Affiliation(s)
- Axel Römer
- Clinical Research Unit, Center of Internal Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany
| | - Divya Rawat
- Clinical Research Unit, Center of Internal Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany
| | - Thomas Linn
- Clinical Research Unit, Center of Internal Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany
| | - Sebastian F Petry
- Clinical Research Unit, Center of Internal Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany
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The Taurine-Conjugated Bile Acid (TUDCA) Normalizes Insulin Secretion in Pancreatic β-Cells Exposed to Fatty Acids: The Role of Mitochondrial Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1370:293-303. [DOI: 10.1007/978-3-030-93337-1_28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Shen Z, Zhu W, Du L. Analysis of Gene Expression Profiles in the Liver of Rats With Intrauterine Growth Retardation. Front Pediatr 2022; 10:801544. [PMID: 35321016 PMCID: PMC8934861 DOI: 10.3389/fped.2022.801544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Intrauterine growth restriction (IUGR) is highly associated with fetal as well as neonatal morbidity, mortality, and an increased risk metabolic disease development later in life. The mechanism involved in the increased risk has not been established. We compared differentially expressed genes between the liver of appropriate for gestational age (AGA) and IUGR rat models and identified their effects on molecular pathways involved in the metabolic syndrome. METHODS We extracted RNA from the liver of IUGR and AGA rats and profiled gene expression by microarray analysis. GO function and KEGG pathway enrichment analyses were conducted using the Search Tool for the Retrieval of Interacting Genes database. Then, the Cytoscape software was used to visualize regulatory interaction networks of IUGR-related genes. The results were further verified via quantitative reverse transcriptase PCR analysis. RESULTS In this study, 815 genes were found to be markedly differentially expressed (fold-change >1.5, p < 0.05) between IUGR and AGA, with 347 genes elevated and 468 suppressed in IUGR, relative to AGA. Enrichment and protein-protein interaction network analyses of target genes revealed that core genes including Ppargc1a, Prkaa2, Slc2a1, Rxrg, and Gcgr, and pathways, including the PPAR signaling pathway and FoxO signaling pathway, had a potential association with metabolic syndrome development in IUGR. We also confirmed that at the mRNA level, five genes involved in glycometabolism were differentially expressed between IUGR and AGA. CONCLUSION Our findings elucidate on differential gene expression profiles in IUGR and AGA. Moreover, they elucidate on the pathogenesis of IUGR-associated metabolic syndromes. The suggested candidates are potential biomarkers and eventually intended to treat them appropriately.
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Affiliation(s)
- Zheng Shen
- Department of Clinical Laboratory, Zhejiang University School of Medicine Children's Hospital, Hangzhou, China.,National Clinical Research Center for Child Health, Hangzhou, China
| | - Weifen Zhu
- Department of Endocrinology, Zhejiang University School of Medicine Sir Run Run Shaw Hospital, Hangzhou, China
| | - Lizhong Du
- National Clinical Research Center for Child Health, Hangzhou, China.,Department of Neonatology, Zhejiang University School of Medicine Children's Hospital, Hangzhou, China
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Jouvet N, Bouyakdan K, Campbell SA, Baldwin C, Townsend SE, Gannon MA, Poitout V, Alquier T, Estall JL. The Tetracycline-Controlled Transactivator (Tet-On/Off) System in β-Cells Reduces Insulin Expression and Secretion in Mice. Diabetes 2021; 70:2850-2859. [PMID: 34610983 PMCID: PMC8660978 DOI: 10.2337/db21-0147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 09/29/2021] [Indexed: 11/13/2022]
Abstract
Controllable genetic manipulation is an indispensable tool in research, greatly advancing our understanding of cell biology and physiology. However in β-cells, transgene silencing, low inducibility, ectopic expression, and off-targets effects are persistent challenges. In this study, we investigated whether an inducible Tetracycline (Tet)-Off system with β-cell-specific mouse insulin promoter (MIP)-itTA-driven expression of tetracycline operon (TetO)-CreJaw/J could circumvent previous issues of specificity and efficacy. Following assessment of tissue-specific gene recombination, β-cell architecture, in vitro and in vivo glucose-stimulated insulin secretion, and whole-body glucose homeostasis, we discovered that expression of any tetracycline-controlled transactivator (e.g., improved itTA, reverse rtTA, or tTA) in β-cells significantly reduced Insulin gene expression and decreased insulin content. This translated into lower pancreatic insulin levels and reduced insulin secretion in mice carrying any tTA transgene, independent of Cre recombinase expression or doxycycline exposure. Our study echoes ongoing challenges faced by fundamental researchers working with β-cells and highlights the need for consistent and comprehensive controls when using the tetracycline-controlled transactivator systems (Tet-On or Tet-Off) for genome editing.
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Affiliation(s)
- Nathalie Jouvet
- Institut de recherches cliniques de Montréal (IRCM), Montréal, Quebec, Canada
| | - Khalil Bouyakdan
- Montreal Diabetes Research Centre, Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Quebec, Canada
| | - Scott A Campbell
- Montreal Diabetes Research Centre, Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Quebec, Canada
- Département de Médecine, Université de Montréal, Montréal, Quebec, Canada
| | - Cindy Baldwin
- Institut de recherches cliniques de Montréal (IRCM), Montréal, Quebec, Canada
| | - Shannon E Townsend
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Maureen A Gannon
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Department of Veterans Affairs, Tennessee Valley Health Authority, Nashville, TN
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Vincent Poitout
- Montreal Diabetes Research Centre, Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Quebec, Canada
- Département de Médecine, Université de Montréal, Montréal, Quebec, Canada
| | - Thierry Alquier
- Montreal Diabetes Research Centre, Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Quebec, Canada
- Département de Médecine, Université de Montréal, Montréal, Quebec, Canada
| | - Jennifer L Estall
- Institut de recherches cliniques de Montréal (IRCM), Montréal, Quebec, Canada
- Montreal Diabetes Research Centre, Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Quebec, Canada
- Département de Médecine, Université de Montréal, Montréal, Quebec, Canada
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The effect of gestational diabetes on the expression of mitochondrial fusion proteins in placental tissue. Placenta 2021; 115:106-114. [PMID: 34600274 DOI: 10.1016/j.placenta.2021.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 09/08/2021] [Accepted: 09/21/2021] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Gestational diabetes mellitus (GDM) poses a risk factor for fetal mortality and morbidity by directly affecting the placenta and fetus. Mitochondria are dynamic organelles that play a key role in energy production and conversion in placental tissue. Mitochondrial fusion and fission proteins are important in terms of providing mitochondrial dynamics, the adaptation of the cell to different conditions, and maintaining the metabolic stability of the cells. Although GDM shares many features with Type 2 diabetes mellitus (T2DM), different effects of these conditions on the mother and the child suggest that GDM may have specific pathological effects on placental cells. The aim of this study is to investigate the expression of mitochondrial dynamics, and mitochondrial protein folding markers in placentas from GDM patients and women with pre-existing diabetes mellitus. METHODS Placentas were properly collected from women, who had pre-existing diabetes (Pre-DM), from women with gestational diabetes mellitus (GDM) and from healthy (non-diabetic) pregnant women. Levels of mitochondrial fusion markers were determined in these placentas by real time quantitative PCR and Western blot experiments. RESULTS mRNA expressions and protein levels of mitochondrial fusion markers, mitofusin 1, mitofusin 2 (MFN1 and MFN2) and optical atrophy 1 (OPA1) proteins were found to be significantly lower in both Pre-DM placentas and those with GDM compared to healthy (non-diabetic) control group. Likewise, proteins involved in mitochondrial protein folding were also found to be significantly reduced compared to control group. DISCUSSION Diabetes during pregnancy leads to processes that correlate with mitochondria dysfunction in placenta. Our results showed that mitochondrial fusion markers significantly decrease in placental tissue of women with GDM, compared to the healthy non-diabetic women. The decrease in mitochondrial fusion markers was more severe during GDM compared to the Pre-DM. Our results suggest that there may be differences in the pathophysiology of these conditions.
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Li LY, Yang Q, Jiang YY, Yang W, Jiang Y, Li X, Hazawa M, Zhou B, Huang GW, Xu XE, Gery S, Zhang Y, Ding LW, Ho AS, Zumsteg ZS, Wang MR, Fullwood MJ, Freedland SJ, Meltzer SJ, Xu LY, Li EM, Koeffler HP, Lin DC. Interplay and cooperation between SREBF1 and master transcription factors regulate lipid metabolism and tumor-promoting pathways in squamous cancer. Nat Commun 2021; 12:4362. [PMID: 34272396 PMCID: PMC8285542 DOI: 10.1038/s41467-021-24656-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 06/29/2021] [Indexed: 02/05/2023] Open
Abstract
Squamous cell carcinomas (SCCs) comprise one of the most common histologic types of human cancer. Transcriptional dysregulation of SCC cells is orchestrated by tumor protein p63 (TP63), a master transcription factor (TF) and a well-researched SCC-specific oncogene. In the present study, both Gene Set Enrichment Analysis (GSEA) of SCC patient samples and in vitro loss-of-function assays establish fatty-acid metabolism as a key pathway downstream of TP63. Further studies identify sterol regulatory element binding transcription factor 1 (SREBF1) as a central mediator linking TP63 with fatty-acid metabolism, which regulates the biosynthesis of fatty-acids, sphingolipids (SL), and glycerophospholipids (GPL), as revealed by liquid chromatography tandem mass spectrometry (LC-MS/MS)-based lipidomics. Moreover, a feedback co-regulatory loop consisting of SREBF1/TP63/Kruppel like factor 5 (KLF5) is identified, which promotes overexpression of all three TFs in SCCs. Downstream of SREBF1, a non-canonical, SCC-specific function is elucidated: SREBF1 cooperates with TP63/KLF5 to regulate hundreds of cis-regulatory elements across the SCC epigenome, which converge on activating cancer-promoting pathways. Indeed, SREBF1 is essential for SCC viability and migration, and its overexpression is associated with poor survival in SCC patients. Taken together, these data shed light on mechanisms of transcriptional dysregulation in cancer, identify specific epigenetic regulators of lipid metabolism, and uncover SREBF1 as a potential therapeutic target and prognostic marker in SCC.
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Affiliation(s)
- Li-Yan Li
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, China.
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Qian Yang
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Yan-Yi Jiang
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Wei Yang
- Departments of Surgery and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Yuan Jiang
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Xiang Li
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, China
| | - Masaharu Hazawa
- Cell-Bionomics Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan
| | - Bo Zhou
- Departments of Surgery and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Guo-Wei Huang
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Xiu-E Xu
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, China
| | - Sigal Gery
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ying Zhang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Ling-Wen Ding
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Allen S Ho
- Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Zachary S Zumsteg
- Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ming-Rong Wang
- State Key Laboratory of Molecular Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Melissa J Fullwood
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Stephen J Freedland
- Division of Urology, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, USA and the Durham VA Medical Center, Durham, NC, USA
| | - Stephen J Meltzer
- Departments of Medicine and Oncology, Johns Hopkins University School of Medicine and Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD, USA
| | - Li-Yan Xu
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, China.
| | - En-Min Li
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, China.
| | - H Phillip Koeffler
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - De-Chen Lin
- Department of Medicine, Samuel Oschin Cancer Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
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Fucoidan and Fucoxanthin Attenuate Hepatic Steatosis and Inflammation of NAFLD through Modulation of Leptin/Adiponectin Axis. Mar Drugs 2021; 19:md19030148. [PMID: 33809062 PMCID: PMC8001566 DOI: 10.3390/md19030148] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/08/2021] [Accepted: 03/08/2021] [Indexed: 02/06/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the emerging cause of chronic liver disease globally and lack of approved therapies. Here, we investigated the feasibility of combinatorial effects of low molecular weight fucoidan and high stability fucoxanthin (LMF-HSFx) as a therapeutic approach against NAFLD. We evaluated the inhibitory effects of LMF-HSFx or placebo in 42 NAFLD patients for 24 weeks and related mechanism in high fat diet (HFD) mice model and HepaRGTM cell line. We found that LMF-HSFx reduces the relative values of alanine aminotransferase, aspartate aminotransferase, total cholesterol, triglyceride, fasting blood glucose and hemoglobin A1c in NAFLD patients. For lipid metabolism, LMF-HSFx reduces the scores of controlled attenuation parameter (CAP) and increases adiponectin and leptin expression. Interestingly, it reduces liver fibrosis in NAFLD patients, either. The proinflammatory cytokines interleukin (IL)-6 and interferon-γ are reduced in LMF-HSFx group. In HFD mice, LMF-HSFx attenuates hepatic lipotoxicity and modulates adipogenesis. Additionally, LMF-HSFx modulates SIRI-PGC-1 pathway in HepaRG cells under palmitic acid-induced lipotoxicity environment. Here, we describe that LMF-HSFx ameliorated hepatic steatosis, inflammation, fibrosis and insulin resistance in NAFLD patients. LMF-HSFx may modulate leptin-adiponectin axis in adipocytes and hepatocytes, then regulate lipid and glycogen metabolism, decrease insulin resistance and is against NAFLD.
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15
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Lipotoxic Impairment of Mitochondrial Function in β-Cells: A Review. Antioxidants (Basel) 2021; 10:antiox10020293. [PMID: 33672062 PMCID: PMC7919463 DOI: 10.3390/antiox10020293] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 02/06/2021] [Accepted: 02/11/2021] [Indexed: 02/08/2023] Open
Abstract
Lipotoxicity is a major contributor to type 2 diabetes mainly promoting mitochondrial dysfunction. Lipotoxic stress is mediated by elevated levels of free fatty acids through various mechanisms and pathways. Impaired peroxisome proliferator-activated receptor (PPAR) signaling, enhanced oxidative stress levels, and uncoupling of the respiratory chain result in ATP deficiency, while β-cell viability can be severely impaired by lipotoxic modulation of PI3K/Akt and mitogen-activated protein kinase (MAPK)/extracellular-signal-regulated kinase (ERK) pathways. However, fatty acids are physiologically required for an unimpaired β-cell function. Thus, preparation, concentration, and treatment duration determine whether the outcome is beneficial or detrimental when fatty acids are employed in experimental setups. Further, ageing is a crucial contributor to β-cell decay. Cellular senescence is connected to loss of function in β-cells and can further be promoted by lipotoxicity. The potential benefit of nutrients has been broadly investigated, and particularly polyphenols were shown to be protective against both lipotoxicity and cellular senescence, maintaining the physiology of β-cells. Positive effects on blood glucose regulation, mitigation of oxidative stress by radical scavenging properties or regulation of antioxidative enzymes, and modulation of apoptotic factors were reported. This review summarizes the significance of lipotoxicity and cellular senescence for mitochondrial dysfunction in the pancreatic β-cell and outlines potential beneficial effects of plant-based nutrients by the example of polyphenols.
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16
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Kim JH, Delghingaro-Augusto V, Chan JY, Laybutt DR, Proietto J, Nolan CJ. The Role of Fatty Acid Signaling in Islet Beta-Cell Adaptation to Normal Pregnancy. Front Endocrinol (Lausanne) 2021; 12:799081. [PMID: 35069446 PMCID: PMC8766493 DOI: 10.3389/fendo.2021.799081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 12/08/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Maintenance of a normal fetal nutrient supply requires major adaptations in maternal metabolic physiology, including of the islet beta-cell. The role of lipid signaling processes in the mechanisms of islet beta-cell adaptation to pregnancy has been minimally investigated. OBJECTIVE To determine the effects of pregnancy on islet fatty acid (FA) metabolic partitioning and FA augmentation of glucose-stimulated insulin secretion (GSIS). METHODS Age matched virgin, early pregnant (gestational day-11, G11) and late pregnant (G19) Sprague-Dawley rats were studied. Fasted and fed state biochemistry, oral glucose tolerance tests (OGTT), and fasted and post-OGTT liver glycogen, were determined to assess in vivo metabolic characteristics. In isolated islets, FA (BSA-bound palmitate 0.25 mmol/l) augmentation of GSIS, FA partitioning into esterification and oxidation processes using metabolic tracer techniques, lipolysis by glycerol release, triacylglycerols (TG) content, and the expression of key beta-cell genes were determined. RESULTS Plasma glucose in pregnancy was lower, including during the OGTT (glucose area under the curve 0-120 min (AUC0-120); 655±24 versus 849±13 mmol.l-1.min; G19 vs virgin; P<0.0001), with plasma insulin concentrations equivalent to those of virgin rats (insulin AUC0-120; 97±7 versus 83±7 ng.ml-1.min; G19 vs virgin; not significant). Liver glycogen was depleted in fasted G19 rats with full recovery after oral glucose. Serum TG increased during pregnancy (4.4±0.4, 6.7±0.5; 17.1±1.5 mmol/l; virgin, G11, G19, P<0.0001), and islet TG content decreased (147±42, 172±27, 73±13 ng/µg protein; virgin, G11, G19; P<0.01). GSIS in isolated islets was increased in G19 compared to virgin rats, and this effect was augmented in the presence of FA. FA esterification into phospholipids, monoacylglycerols and TG were increased, whereas FA oxidation was reduced, in islets of pregnant compared to virgin rats, with variable effects on lipolysis dependent on gestational age. Expression of Ppargc1a, a key regulator of mitochondrial metabolism, was reduced by 51% in G11 and 64% in G19 pregnant rat islets compared to virgin rat islets (P<0.001). CONCLUSION A lowered set-point for islet and hepatic glucose homeostasis in the pregnant rat has been confirmed. Islet adaptation to pregnancy includes increased FA esterification, reduced FA oxidation, and enhanced FA augmentation of glucose-stimulated insulin secretion.
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Affiliation(s)
- Jee-Hye Kim
- Australian National University Medical School, Australian National University, Canberra, ACT, Australia
| | - Viviane Delghingaro-Augusto
- Australian National University Medical School, Australian National University, Canberra, ACT, Australia
- Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Jeng Yie Chan
- Garvan Institute of Medical Research, St Vincent’s Clinical School, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - D. Ross Laybutt
- Garvan Institute of Medical Research, St Vincent’s Clinical School, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - Joseph Proietto
- Department of Medicine (Austin Health), University of Melbourne, Heidelberg Heights, VIC, Australia
| | - Christopher J. Nolan
- Australian National University Medical School, Australian National University, Canberra, ACT, Australia
- Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
- Department of Endocrinology, The Canberra Hospital, Garran, ACT, Australia
- *Correspondence: Christopher J. Nolan,
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17
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Yang J, Bi Y, Liang S, Gu Z, Cheng L, Li C, Li Z, Zhang Y, Hong Y. The in vivo digestibility study of banana flour with high content of resistant starch at different ripening stages. Food Funct 2020; 11:10945-10953. [PMID: 33245312 DOI: 10.1039/d0fo02494e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Resistant starch, a functional food ingredient, can improve the nutritional value of food products. In this study, the in vitro digestibility of starch from banana flour at four ripening stages was evaluated. The result showed that the resistant starch content of banana flour at ripening stage 1 was up to 81%. Furthermore, to explore the effect of resistant starch in the body, the in vivo digestibility of banana flour was investigated. The intake of banana flour at ripening stage 1 resulted in a nearly 70% decrease in the homeostasis model assessment of insulin resistance value, compared to that of the model group. By contrast, the genes related to glucokinase were upregulated by 66%, and the expression level of the insulin receptor gene was increased by more than 1.5 times that of the model group. Thus, natural banana flour has potential for controlling type 2 diabetes mellitus.
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Affiliation(s)
- Jie Yang
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu Province, China
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18
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Wang L, Sun M, Cao Y, Ma L, Shen Y, Velikanova AA, Li X, Sun C, Zhao Y. miR-34a regulates lipid metabolism by targeting SIRT1 in non-alcoholic fatty liver disease with iron overload. Arch Biochem Biophys 2020; 695:108642. [PMID: 33098868 DOI: 10.1016/j.abb.2020.108642] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 10/16/2020] [Accepted: 10/18/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND Micro-ribonucleic acids (miRNAs) have been implicated in the regulation of non-alcoholic fatty liver disease (NAFLD), a leading cause of chronic liver disease worldwide. The mechanisms by which miR-34a influences NAFLD through the Sirtuin 1 (SIRT1)-related pathway were investigated herein. METHODS Male C57BL/6 mice were injected with a miR-34a lentivirus vector inhibitor or control. HepG2 cells were transfected with a miR-34a mimic, inhibitor, SIRT1 small interfering RNA (siRNA), SIRT1 plasmid, and a negative oligonucleotide control to evaluate their role in oleic acid (OA) and excess iron-induced NAFLD. The accumulation of lipids in the mice liver and HepG2 cells was analyzed by triglyceride (TG) detection and hematoxylin and eosin (HE) staining. Additionally, the indexes of oxidative stress related to lipid metabolism were evaluated by western blotting and real-time PCR (qRT-PCR). The levels of intracellular reactive oxygen species (ROS) and mitochondrial membrane potentials were measured by flow cytometry and laser confocal microscopy, respectively. Finally, the dual luciferase reporter assay was conducted to further confirm whether SIRT1 was a direct target of miR-34a. RESULTS Overexpression of miR-34a resulted in increased triglyceride accumulation as well as in decreased mitochondrial membrane potential and SIRT1 levels. Silencing of miR-34a increased SIRT1 expression and alleviated triglyceride accumulation in the presence of OA and iron. Additionally, miR-34a directly inhibited SIRT1 by binding to the 3'-untranslated region, as determined via the luciferase reporter assay. CONCLUSIONS Our results support the existence of a link between the liver cell mitochondria and miR-34a/SIRT1 signaling. Potential endogenous modulators of NAFLD pathogenesis may ultimately provide new tools for therapeutic intervention.
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Affiliation(s)
- Li Wang
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Mengyun Sun
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Yue Cao
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Lingyu Ma
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Yang Shen
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Arina Alekseevna Velikanova
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Xianan Li
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Changhao Sun
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China
| | - Yan Zhao
- Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Hei Longjiang Province, 150081, China.
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Santos JL, Krause BJ, Cataldo LR, Vega J, Salas-Pérez F, Mennickent P, Gallegos R, Milagro FI, Prieto-Hontoria P, Riezu-Boj JI, Bravo C, Salas-Huetos A, Arpón A, Galgani JE, Martínez JA. PPARGC1A Gene Promoter Methylation as a Biomarker of Insulin Secretion and Sensitivity in Response to Glucose Challenges. Nutrients 2020; 12:nu12092790. [PMID: 32933059 PMCID: PMC7551463 DOI: 10.3390/nu12092790] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 12/15/2022] Open
Abstract
Methylation in CpG sites of the PPARGC1A gene (encoding PGC1-α) has been associated with adiposity, insulin secretion/sensitivity indexes and type 2 diabetes. We assessed the association between the methylation profile of the PPARGC1A gene promoter gene in leukocytes with insulin secretion/sensitivity indexes in normoglycemic women. A standard oral glucose tolerance test (OGTT) and an abbreviated version of the intravenous glucose tolerance test (IVGTT) were carried out in n = 57 Chilean nondiabetic women with measurements of plasma glucose, insulin, and C-peptide. Bisulfite-treated DNA from leukocytes was evaluated for methylation levels in six CpG sites of the proximal promoter of the PPARGC1A gene by pyrosequencing (positions -816, -783, -652, -617, -521 and -515). A strong correlation between the DNA methylation percentage of different CpG sites of the PPARGC1A promoter in leukocytes was found, suggesting an integrated epigenetic control of this region. We found a positive association between the methylation levels of the CpG site -783 with the insulin sensitivity Matsuda composite index (rho = 0.31; p = 0.02) derived from the OGTT. The CpG hypomethylation in the promoter position -783 of the PPARGC1A gene in leukocytes may represent a biomarker of reduced insulin sensitivity after the ingestion of glucose.
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Affiliation(s)
- José L. Santos
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
- Correspondence: ; Tel.: +56-2-354-3862; Fax: +56-2-633-8298
| | - Bernardo J. Krause
- Instituto de Ciencias de la Salud, Universidad de O’Higgins, Avenida Libertador Bernardo O’Higgins 611, Rancagua 2841935, Chile; (B.J.K.); (F.S.-P.)
| | - Luis Rodrigo Cataldo
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
| | - Javier Vega
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
| | - Francisca Salas-Pérez
- Instituto de Ciencias de la Salud, Universidad de O’Higgins, Avenida Libertador Bernardo O’Higgins 611, Rancagua 2841935, Chile; (B.J.K.); (F.S.-P.)
- Department of Nutrition, Food Sciences and Physiology, Centre for Nutrition Research, University of Navarra, 31008 Pamplona, Spain; (F.I.M.); (J.I.R.-B.); (A.A.); (J.A.M.)
| | - Paula Mennickent
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
| | - Raúl Gallegos
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
| | - Fermín I. Milagro
- Department of Nutrition, Food Sciences and Physiology, Centre for Nutrition Research, University of Navarra, 31008 Pamplona, Spain; (F.I.M.); (J.I.R.-B.); (A.A.); (J.A.M.)
- Centro de Investigación Biomédica en Red de la Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain
- IdiSNA, Navarra’s Health Research Institute, 31008 Pamplona, Spain
| | | | - J. Ignacio Riezu-Boj
- Department of Nutrition, Food Sciences and Physiology, Centre for Nutrition Research, University of Navarra, 31008 Pamplona, Spain; (F.I.M.); (J.I.R.-B.); (A.A.); (J.A.M.)
- IdiSNA, Navarra’s Health Research Institute, 31008 Pamplona, Spain
| | - Carolina Bravo
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
| | - Albert Salas-Huetos
- Andrology and IVF Laboratory, Division of Urology, Department of Surgery, University of Utah School of Medicine, Salt Lake City, UT 84108, USA;
| | - Ana Arpón
- Department of Nutrition, Food Sciences and Physiology, Centre for Nutrition Research, University of Navarra, 31008 Pamplona, Spain; (F.I.M.); (J.I.R.-B.); (A.A.); (J.A.M.)
| | - José E. Galgani
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (L.R.C.); (J.V.); (P.M.); (R.G.); (C.B.); (J.E.G.)
- Departamento de Ciencias de la Salud, Nutrición y Dietética, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 781000, Chile
| | - J. Alfredo Martínez
- Department of Nutrition, Food Sciences and Physiology, Centre for Nutrition Research, University of Navarra, 31008 Pamplona, Spain; (F.I.M.); (J.I.R.-B.); (A.A.); (J.A.M.)
- Centro de Investigación Biomédica en Red de la Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain
- IdiSNA, Navarra’s Health Research Institute, 31008 Pamplona, Spain
- IMDEA-Food, 28049 Madrid, Spain
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20
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Osipovich AB, Stancill JS, Cartailler JP, Dudek KD, Magnuson MA. Excitotoxicity and Overnutrition Additively Impair Metabolic Function and Identity of Pancreatic β-Cells. Diabetes 2020; 69:1476-1491. [PMID: 32332159 PMCID: PMC7809715 DOI: 10.2337/db19-1145] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/20/2020] [Indexed: 12/14/2022]
Abstract
A sustained increase in intracellular Ca2+ concentration (referred to hereafter as excitotoxicity), brought on by chronic metabolic stress, may contribute to pancreatic β-cell failure. To determine the additive effects of excitotoxicity and overnutrition on β-cell function and gene expression, we analyzed the impact of a high-fat diet (HFD) on Abcc8 knockout mice. Excitotoxicity caused β-cells to be more susceptible to HFD-induced impairment of glucose homeostasis, and these effects were mitigated by verapamil, a Ca2+ channel blocker. Excitotoxicity, overnutrition, and the combination of both stresses caused similar but distinct alterations in the β-cell transcriptome, including additive increases in genes associated with mitochondrial energy metabolism, fatty acid β-oxidation, and mitochondrial biogenesis and their key regulator Ppargc1a Overnutrition worsened excitotoxicity-induced mitochondrial dysfunction, increasing metabolic inflexibility and mitochondrial damage. In addition, excitotoxicity and overnutrition, individually and together, impaired both β-cell function and identity by reducing expression of genes important for insulin secretion, cell polarity, cell junction, cilia, cytoskeleton, vesicular trafficking, and regulation of β-cell epigenetic and transcriptional program. Sex had an impact on all β-cell responses, with male animals exhibiting greater metabolic stress-induced impairments than females. Together, these findings indicate that a sustained increase in intracellular Ca2+, by altering mitochondrial function and impairing β-cell identity, augments overnutrition-induced β-cell failure.
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Affiliation(s)
- Anna B Osipovich
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
| | - Jennifer S Stancill
- Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | | | - Karrie D Dudek
- Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Mark A Magnuson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
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Laureano-Melo R, Império GE, Kluck GEG, da Conceição RR, de Souza JS, Marinho BG, Giannocco G, Côrtes WS. Selenium supplementation during pregnancy and lactation promotes metabolic changes in Wistar rats' offspring. Clin Exp Pharmacol Physiol 2020; 47:1272-1282. [PMID: 31997362 DOI: 10.1111/1440-1681.13268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 01/10/2020] [Accepted: 01/26/2020] [Indexed: 11/30/2022]
Abstract
Epidemiological and animal studies have demonstrated a strong association between selenium (Se) supplementation and metabolic disorders, we aimed to evaluate whether maternal Se supplementation was able to change metabolic parameters in rats' offspring. Moreover, as Se is a deiodinase (DIO) cofactor, we decided to investigate how thyroid hormones (THs) would be involved in such metabolic changes. Thereby, two groups (n = 6, ~250 g) of female Wistar rats underwent isotonic saline or sodium selenite (1 mg/kg, p.o.) treatments. Although there were no significant differences in body weight between groups, the Se treatment during pregnancy and lactation increased milk intake and the visceral white adipose tissue (WAT) in offspring. The rats whose mothers were treated with Se also presented an improvement in the glucose tolerance test and in the glucose-stimulated insulin secretion. Regarding the lipid metabolism, the Se group had a reduction of triglycerides in the liver and in WAT. These metabolic changes were accompanied by an increase in serum triiodothyronine (T3 ) and in DIO 2 expression in brown adipose tissue (BAT). We further demonstrate an increased expression of peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) and nuclear respiratory factor-1 (NRF-1) mRNA in the liver. In adulthood offspring, Se supplementation programs thyroid function, glucose homeostasis, and feeding behaviour. Taken together, there is no indication that Se programming causes insulin resistance. Moreover, we conjecture that these metabolic responses are induced by increased thyroxine (T4 ) to T3 conversion by DIO2 in BAT and mediated by altered transcription factors expression associated with oxidative metabolism control in the liver.
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Affiliation(s)
- Roberto Laureano-Melo
- Department of Physiological Sciences, Multicenter Graduate Program in Physiological Sciences, Institute of Health and Biological Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Brazil
| | - Güínever E Império
- Laboratory of Translational Endocrinology, Institute of Biophysics Carlos Chagas Filho, Rio de Janeiro, Brazil
| | - George E G Kluck
- Laboratory of Lipids and Lipoproteins Biochemistry, Institute of Medical Biochemistry, UFRJ, Rio de Janeiro, Brazil
| | - Rodrigo R da Conceição
- Molecular and Translational Endocrinology Laboratory, Department of Medicine, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Janaina S de Souza
- Molecular and Translational Endocrinology Laboratory, Department of Medicine, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Bruno G Marinho
- Department of Physiological Sciences, Multicenter Graduate Program in Physiological Sciences, Institute of Health and Biological Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Brazil
| | - Gisele Giannocco
- Molecular and Translational Endocrinology Laboratory, Department of Medicine, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Wellington S Côrtes
- Department of Physiological Sciences, Multicenter Graduate Program in Physiological Sciences, Institute of Health and Biological Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Brazil
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Liu Y, Xu F, Jiang P. Effect of sitagliptin on expression of skeletal muscle peroxisome proliferator-activated receptor γ coactivator-1 α and irisin in a rat model of type 2 diabetes mellitus. J Int Med Res 2020; 48:300060519885569. [PMID: 32364035 PMCID: PMC7218978 DOI: 10.1177/0300060519885569] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 10/07/2019] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To evaluate the effect of sitagliptin on skeletal muscle expression of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), irisin, and phosphoadenylated adenylate activated protein kinase (p-AMPK) in a rat model of type 2 diabetes mellitus (T2DM). METHODS A high-fat diet/streptozotocin T2DM rat model was established. Rats were divided into T2DM, low-dose sitagliptin (ST1), high-dose sitagliptin (ST2), and normal control groups (NC). PGC-1α, irisin, and p-AMPK protein levels in skeletal muscle were measured by western blot, and PCG-1α and Fndc5 mRNA levels were assessed by reverse transcription-polymerase chain reaction. RESULTS Fasting plasma glucose (FPG), fasting insulin (FIns), homeostatic model assessment-insulin resistance (HOMA-IR), and tumor necrosis factor-α (TNF-α) were significantly up-regulated in the T2DM compared with the other groups, and FPG, FIns, total cholesterol, triglycerides, TNF-α, and HOMA-IR were significantly down-regulated in the ST2 compared with the ST1 group. PGC-1α, irisin, and p-AMPK expression levels decreased successively in the ST2, ST1, and DM groups compared with the NC, and were all significantly up-regulated in the ST2 compared with the ST1 group. CONCLUSION Down-regulation of PGC-1α and irisin in skeletal muscle may be involved in T2DM. Sitagliptin can dose-dependently up-regulate PCG-1α and irisin, potentially improving insulin resistance and glycolipid metabolism and inhibiting inflammation.
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MESH Headings
- AMP-Activated Protein Kinase Kinases
- Animals
- Diabetes Mellitus, Experimental/drug therapy
- Diabetes Mellitus, Experimental/etiology
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/etiology
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Diet, High-Fat/adverse effects
- Dose-Response Relationship, Drug
- Down-Regulation
- Fibronectins/analysis
- Fibronectins/metabolism
- Glycolipids/metabolism
- Humans
- Hypoglycemic Agents/administration & dosage
- Male
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/immunology
- Muscle, Skeletal/metabolism
- Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/analysis
- Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism
- Protein Kinases/analysis
- Protein Kinases/metabolism
- Rats
- Sitagliptin Phosphate/administration & dosage
- Streptozocin/toxicity
- Up-Regulation
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Affiliation(s)
- Yuntao Liu
- Department of Endocrinology, Affiliated Renhe Hospital of China Three Gorges University, The Second Clinical Medical College of China Three Gorges University, Yichang, China
| | - Feng Xu
- Yichang Hospital of Traditional Chinese Medicine, Clinical Medical College of Traditional Chinese Medicine, China Three Gorges University, Yichang, China
| | - Pan Jiang
- Department of Endocrinology, Affiliated Renhe Hospital of China Three Gorges University, The Second Clinical Medical College of China Three Gorges University, Yichang, China
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Fontecha-Barriuso M, Martin-Sanchez D, Martinez-Moreno JM, Monsalve M, Ramos AM, Sanchez-Niño MD, Ruiz-Ortega M, Ortiz A, Sanz AB. The Role of PGC-1α and Mitochondrial Biogenesis in Kidney Diseases. Biomolecules 2020; 10:biom10020347. [PMID: 32102312 PMCID: PMC7072614 DOI: 10.3390/biom10020347] [Citation(s) in RCA: 125] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 02/17/2020] [Accepted: 02/19/2020] [Indexed: 02/06/2023] Open
Abstract
Chronic kidney disease (CKD) is one of the fastest growing causes of death worldwide, emphasizing the need to develop novel therapeutic approaches. CKD predisposes to acute kidney injury (AKI) and AKI favors CKD progression. Mitochondrial derangements are common features of both AKI and CKD and mitochondria-targeting therapies are under study as nephroprotective agents. PGC-1α is a master regulator of mitochondrial biogenesis and an attractive therapeutic target. Low PGC-1α levels and decreased transcription of its gene targets have been observed in both preclinical AKI (nephrotoxic, endotoxemia, and ischemia-reperfusion) and in experimental and human CKD, most notably diabetic nephropathy. In mice, PGC-1α deficiency was associated with subclinical CKD and predisposition to AKI while PGC-1α overexpression in tubular cells protected from AKI of diverse causes. Several therapeutic strategies may increase kidney PGC-1α activity and have been successfully tested in animal models. These include AMP-activated protein kinase (AMPK) activators, phosphodiesterase (PDE) inhibitors, and anti-TWEAK antibodies. In conclusion, low PGC-1α activity appears to be a common feature of AKI and CKD and recent characterization of nephroprotective approaches that increase PGC-1α activity may pave the way for nephroprotective strategies potentially effective in both AKI and CKD.
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Affiliation(s)
- Miguel Fontecha-Barriuso
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
| | - Diego Martin-Sanchez
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
| | - Julio Manuel Martinez-Moreno
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
| | - Maria Monsalve
- Instituto de Investigaciones Biomédicas “Alberto Sols” (CSIC-UAM), 28029 Madrid, Spain;
| | - Adrian Mario Ramos
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
| | - Maria Dolores Sanchez-Niño
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
| | - Marta Ruiz-Ortega
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
- School of Medicine, UAM, 28029 Madrid, Spain
| | - Alberto Ortiz
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
- School of Medicine, UAM, 28029 Madrid, Spain
- IRSIN, 28040 Madrid, Spain
| | - Ana Belen Sanz
- Research Institute-Fundacion Jimenez Diaz, Autonoma University, 28040 Madrid, Spain; (M.F.-B.); (D.M.-S.); (J.M.M.-M.); (A.M.R.); (M.D.S.-N.); (M.R.-O.); (A.O.)
- REDINREN, 28040 Madrid, Spain
- Correspondence: ; Tel.: +34-91-550-48-00
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Ferreira SM, Costa-Júnior JM, Kurauti MA, Leite NC, Ortis F, Rezende LF, Barbosa HC, Boschero AC, Santos GJ. ARHGAP21 Acts as an Inhibitor of the Glucose-Stimulated Insulin Secretion Process. Front Endocrinol (Lausanne) 2020; 11:599165. [PMID: 33324349 PMCID: PMC7726208 DOI: 10.3389/fendo.2020.599165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/26/2020] [Indexed: 12/17/2022] Open
Abstract
ARHGAP21 is a RhoGAP protein implicated in the modulation of insulin secretion and energy metabolism. ARHGAP21 transient-inhibition increase glucose-stimulated insulin secretion (GSIS) in neonatal islets; however, ARHGAP21 heterozygote mice have a reduced insulin secretion. These discrepancies are not totally understood, and it might be related to functional maturation of beta cells and peripheral sensitivity. Here, we investigated the real ARHGAP21 role in the insulin secretion process using an adult mouse model of acute ARHGAP21 inhibition, induced by antisense. After ARHGAP21 knockdown induction by antisense injection in 60-day old male mice, we investigated glucose and insulin tolerance test, glucose-induced insulin secretion, glucose-induced intracellular calcium dynamics, and gene expression. Our results showed that ARHGAP21 acts negatively in the GSIS of adult islet. This effect seems to be due to the modulation of important points of insulin secretion process, such as the energy metabolism (PGC1α), Ca2+ signalization (SYTVII), granule-extrusion (SNAP25), and cell-cell interaction (CX36). Therefore, based on these finds, ARHGAP21 may be an important target in Diabetes Mellitus (DM) treatment.
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Affiliation(s)
- Sandra M. Ferreira
- Obestity and Comorbidities Research Center/Biology Institute, University State of Campinas (UNICAMP), Campinas, Brazil
| | - José M. Costa-Júnior
- Obestity and Comorbidities Research Center/Biology Institute, University State of Campinas (UNICAMP), Campinas, Brazil
| | - Mirian A. Kurauti
- Departament Physiological Sciences, University State of Maringá (UEM), Maringá, Brazil
| | - Nayara C. Leite
- Obestity and Comorbidities Research Center/Biology Institute, University State of Campinas (UNICAMP), Campinas, Brazil
| | - Fernanda Ortis
- Department of Cellular Biology and Development, Institute of Biomedical Sciences, University State of São Paulo (USP), São Paulo, Brazil
| | - Luiz F. Rezende
- Departament of Physiopathology, University State of Montes Claros (UNIMONTES), Montes Claros, Brazil
| | - Helena C. Barbosa
- Obestity and Comorbidities Research Center/Biology Institute, University State of Campinas (UNICAMP), Campinas, Brazil
| | - Antonio C. Boschero
- Obestity and Comorbidities Research Center/Biology Institute, University State of Campinas (UNICAMP), Campinas, Brazil
| | - Gustavo J. Santos
- Departament of Physiological Sciences, Center for Biological Sciences, University Federal of Santa Catarina (UFSC), Florianópolis, Brazil
- *Correspondence: Gustavo J. Santos,
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25
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Zhu N, Yan X, Li H, Wang H. Clinical Significance of Serum PGC-1 Alpha Levels in Diabetes Mellitus with Myocardial Infarction Patients and Reduced ROS-Oxidative Stress in Diabetes Mellitus with Myocardial Infarction Model. Diabetes Metab Syndr Obes 2020; 13:4041-4049. [PMID: 33149643 PMCID: PMC7604475 DOI: 10.2147/dmso.s276163] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 09/19/2020] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND In this study, we explored the clinical significance of serum peroxisome proliferator-activated receptor gamma co-activator 1 (PGC-1) alpha levels in diabetes mellitus with myocardial infarction (DMMI) patients and investigated the possible mechanism. MATERIALS AND METHODS Serum samples were obtained from patients with DMMI or normal volunteer in Baoding First Center Hospital. C57BL/6 mice were induced by a single intraperitoneal (i.p.) injection of 100 mg/kg STZ (streptozocin) for in vivo model. Human myocardial cell lines H9C2 cells were induced with high glucose medium (33 mmol/L glucose) for in vitro model. Western blot was used to analyze the protein expressions in this study. RESULTS Serum PGC-1 alpha levels were down-regulated in patients with DMMI. There was negative correlation between serum PGC-1 alpha levels and glycated hemoglobin, blood glucose or glucagon in DMMI patients. Recombination of PGC-1 alpha protein decreased the levels of glycated hemoglobin, blood glucose and glucagon, and inhibited oxidative stress and myocardial damage in mice of DMMI. Over-expression of PGC-1 alpha reduced reactive oxygen species (ROS)-oxidative stress, while down-regulation of PGC-1 alpha promoted ROS-oxidative stress via regulation of hemeoxygenase-1 (HO-1) expression in in vitro model of DMMI. The inhibition of HO-1 expression attenuated the anti-oxidation effects of PGC-1 alpha in vitro. CONCLUSION PGC-1 alpha attenuated ROS-oxidative stress in diabetic cardiomyopathy model, and PGC-1 alpha served as a potential intervention to alleviate DMMI in clinical applications.
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Affiliation(s)
- Ning Zhu
- Department 1 of Cardiology, Baoding First Center Hospital, Baoding071002, Hebei, People’s Republic of China
- Correspondence: Ning ZhuDepartment 1 of Cardiology, Baoding First Center Hospital, 320 Changchengbeidajie, Baoding071002, Hebei, People’s Republic of ChinaTel +86-312-5096409 Email
| | - Xue Yan
- Department 1 of Cardiology, Baoding First Center Hospital, Baoding071002, Hebei, People’s Republic of China
| | - Hongli Li
- Department 1 of Cardiology, Baoding First Center Hospital, Baoding071002, Hebei, People’s Republic of China
| | - Huiqin Wang
- Department 1 of Cardiology, Baoding First Center Hospital, Baoding071002, Hebei, People’s Republic of China
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Bhatta P, Bermano G, Williams HC, Knott RM. Meta-analysis demonstrates Gly482Ser variant of PPARGC1A is associated with components of metabolic syndrome within Asian populations. Genomics 2019; 112:1795-1803. [PMID: 31678594 DOI: 10.1016/j.ygeno.2019.10.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/11/2019] [Accepted: 10/17/2019] [Indexed: 11/18/2022]
Abstract
AIM To determine the association of peroxisome proliferator activated receptor gamma coactivator 1 Gly482Ser variant with components of metabolic syndrome. MATERIALS AND METHODS A systematic search was carried out using Web of Science, PubMed, EMBASE and the Cochrane library using the key words: Peroxisome proliferator activator receptor gamma coactivator 1, PPARGC1A, PGC-1, PGC-1alpha, and PGC1alpha alone or with polymorphism, Gly482Ser and rs8192678. RESULTS Data from 19 articles generated 28 separate data sets. Under the recessive model fasting plasma glucose was significantly lower in AA genotypes when compared to GG + GA in the total sample group and in non-Asian group (p < .001). The AA genotype showed significantly lower levels of total cholesterol compared to GG + GA genotype using the recessive model with the non-Asian group (p < .05). Under the dominant model, body mass index of the GG genotype was significantly higher in Asian subgroups (p < .05). CONCLUSION PPARGC1A Gly482Ser variant impacts differently in Asian population groups.
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Affiliation(s)
- Prabhakar Bhatta
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB107GJ, UK
| | - Giovanna Bermano
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB107GJ, UK
| | - Hector C Williams
- School of Health Sciences, Robert Gordon University, Aberdeen AB107GJ, UK
| | - Rachel M Knott
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB107GJ, UK.
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27
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Yang Y, Gao H, Zhou H, Liu Q, Qi Z, Zhang Y, Zhang J. The role of mitochondria-derived peptides in cardiovascular disease: Recent updates. Biomed Pharmacother 2019; 117:109075. [DOI: 10.1016/j.biopha.2019.109075] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/28/2019] [Accepted: 06/02/2019] [Indexed: 12/20/2022] Open
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Role of PGC-1α in Mitochondrial Quality Control in Neurodegenerative Diseases. Neurochem Res 2019; 44:2031-2043. [PMID: 31410709 DOI: 10.1007/s11064-019-02858-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/17/2019] [Accepted: 08/08/2019] [Indexed: 12/13/2022]
Abstract
As one of the major cell organelles responsible for ATP production, it is important that neurons maintain mitochondria with structural and functional integrity; this is especially true for neurons with high metabolic requirements. When mitochondrial damage occurs, mitochondria are able to maintain a steady state of functioning through molecular and organellar quality control, thus ensuring neuronal function. And when mitochondrial quality control (MQC) fails, mitochondria mediate apoptosis. An apparently key molecule in MQC is the transcriptional coactivator peroxisome proliferator activated receptor γ coactivator-1α (PGC-1α). Recent findings have demonstrated that upregulation of PGC-1α expression in neurons can modulate MQC to prevent mitochondrial dysfunction in certain in vivo and in vitro aging or neurodegenerative encephalopathy models, such as Huntington's disease, Alzheimer's disease, and Parkinson's disease. Because mitochondrial function and quality control disorders are the basis of pathogenesis in almost all neurodegenerative diseases (NDDs), the role of PGC-1α may make it a viable entry point for the treatment of such diseases. This review focuses on multi-level MQC in neurons, as well as the regulation of MQC by PGC-1α in these major NDDs.
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Yuan D, Xiao D, Gao Q, Zeng L. PGC-1α activation: a therapeutic target for type 2 diabetes? Eat Weight Disord 2019; 24:385-395. [PMID: 30498989 DOI: 10.1007/s40519-018-0622-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 11/24/2018] [Indexed: 12/19/2022] Open
Abstract
Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) has gained popularity as a very attractive target for diabetic therapies due to its role in lipid and glucose metabolism. Pharmacological activation of PGC-1α is thought to elicit health benefits. However, this notion has been questioned by increasing evidence, which suggests that insulin resistant is exacerbated when PGC-1α expression is far beyond normal physiological limits and is prevented under the condition of PGC-1α deficiency. This narrative review suggests that PGC-1α, as a master metabolic regulator, exerts roles in insulin sensitivity in a tissue-specific manner and in a physical activity/age-dependent fashion. When using PGC-1α as a target for therapeutic strategies against insulin resistance and T2DM, we should take these factors into consideration.Level of evidence: Level V, narrative review.
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Affiliation(s)
- Daixiu Yuan
- Department of Medicine, Jishou University, Jishou, 41600, Hunan, China
| | - Dingfu Xiao
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, Hunan, China
| | - Qian Gao
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, Hunan, China
| | - Liming Zeng
- Science College of Jiangxi Agricultural University, Nanchang, 330045, Jiangxi, China.
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Wang J, Gou W, Kim DS, Strange C, Wang H. Clathrin-mediated Endocytosis of Alpha-1 Antitrypsin is Essential for its Protective Function in Islet Cell Survival. Am J Cancer Res 2019; 9:3940-3951. [PMID: 31281523 PMCID: PMC6587339 DOI: 10.7150/thno.31647] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 04/01/2019] [Indexed: 12/28/2022] Open
Abstract
Cytokine-induced pancreatic β cell death plays a pivotal role in both type 1 and type 2 diabetes. Our previous study showed that alpha-1 antitrypsin (AAT) inhibits β cell death through the suppression of cytokine-induced c-Jun N-terminal kinase (JNK) activation in an islet transplantation model. The aim of this study was to further understand how AAT impacts β cells by studying AAT endocytosis in human islets and a βTC3 murine insulinoma cell line. Methods: In vitro, human islets and βTC3 cells were stimulated with cytokines in the presence or absence of chlorpromazine (CPZ), a drug that disrupts clathrin-mediated endocytosis. Western blot, real-time PCR and cell death ELISA were performed to investigate β cell death. The oxygen consumption rate (OCR) was measured on human islets. In vivo, islets were harvested from C57BL/6 donor mice treated with saline or human AAT and transplanted into the livers of syngeneic mice that had been rendered diabetic by streptozotocin (STZ). Islet graft survival and function were analyzed. Results: AAT was internalized by β cells in a time- and dose-dependent manner. AAT internalization was mediated by clathrin as treatment with CPZ, profoundly decreased AAT internalization, cytokine-induced JNK activation and the downstream upregulation of c-Jun mRNA expression. Similarly, addition of CPZ attenuated cytokine-induced caspase 9 cleavage (c-casp 9) and DNA fragmentation, which was suppressed by AAT. Treatment of donor mice with AAT produced AAT internalization in islets, and resulted in a higher percentage of recipients reaching normoglycemia after syngeneic intraportal islet transplantation. Conclusion: Our results suggest that AAT is internalized by β cells through clathrin-mediated endocytosis that leads to the suppression of caspase 9 activation. This process is required for the protective function of AAT in islets when challenged with proinflammatory cytokines or after islet transplantation.
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Metabolic aspects in NAFLD, NASH and hepatocellular carcinoma: the role of PGC1 coactivators. Nat Rev Gastroenterol Hepatol 2019; 16:160-174. [PMID: 30518830 DOI: 10.1038/s41575-018-0089-3] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alterations of hepatic metabolism are critical to the development of liver disease. The peroxisome proliferator-activated receptor-γ coactivators (PGC1s) are able to orchestrate, on a transcriptional level, different aspects of liver metabolism, such as mitochondrial oxidative phosphorylation, gluconeogenesis and fatty acid synthesis. As modifications affecting both mitochondrial and lipid metabolism contribute to the initiation and/or progression of liver steatosis, nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC), a link between disrupted PGC1 pathways and onset of these pathological conditions has been postulated. However, despite the large quantity of studies, the scenario is still not completely understood, and some issues remain controversial. Here, we discuss the roles of PGC1s in healthy liver and explore their contribution to the pathogenesis and future therapy of NASH and HCC.
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PGC1A regulates the IRS1:IRS2 ratio during fasting to influence hepatic metabolism downstream of insulin. Proc Natl Acad Sci U S A 2019; 116:4285-4290. [PMID: 30770439 PMCID: PMC6410797 DOI: 10.1073/pnas.1815150116] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Precise modulation of hepatic glucose metabolism is crucial during the fasting and feeding cycle and is controlled by the actions of circulating insulin and glucagon. The insulin-signaling pathway requires insulin receptor substrate 1 (IRS1) and IRS2, which are found to be dysregulated in diabetes and obesity. The peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1A) is a fasting-induced transcriptional coactivator. In nonalcoholic fatty liver disease and in patients with type 2 diabetes, low hepatic PGC1A levels are associated with insulin resistance. However, how PGC1A activity impacts the hepatic insulin-signaling pathway is still unclear. We used gain- and loss-of-function models in mouse primary hepatocytes and measured hepatocyte insulin response by gene and protein expression and ex vivo glucose production. We found that the PGC1A level determines the relative ratio of IRS1 and IRS2 in hepatocytes, impacting insulin receptor signaling via protein kinase B/AKT (AKT). PGC1A drove the expression of IRS2 downstream of glucagon signaling while simultaneously reducing IRS1 expression. We illustrate that glucagon- or PGC1A-induced IRS2 expression was dependent on cAMP Response Element Binding Protein activity and that this was essential for suppression of hepatocyte gluconeogenesis in response to insulin in vitro. We also show that increased hepatic PGC1A improves glucose homeostasis in vivo, revealing a counterregulatory role for PGC1A in repressing uncontrolled glucose production in response to insulin signaling. These data highlight a mechanism by which PGC1A plays dual roles in the control of gluconeogenesis during the fasting-to-fed transition through regulated balance between IRS1 and IRS2 expression.
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Ji J, Petropavlovskaia M, Khatchadourian A, Patapas J, Makhlin J, Rosenberg L, Maysinger D. Type 2 diabetes is associated with suppression of autophagy and lipid accumulation in β-cells. J Cell Mol Med 2019; 23:2890-2900. [PMID: 30710421 PMCID: PMC6433726 DOI: 10.1111/jcmm.14172] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 12/14/2018] [Accepted: 12/29/2018] [Indexed: 01/05/2023] Open
Abstract
Both type 2 diabetes (T2D) and obesity are characterized by excessive hyperlipidaemia and subsequent lipid droplet (LD) accumulation in adipose tissue. To investigate whether LDs also accumulate in β-cells of T2D patients, we assessed the expression of PLIN2, a LD-associated protein, in non-diabetic (ND) and T2D pancreata. We observed an up-regulation of PLIN2 mRNA and protein in β-cells of T2D patients, along with significant changes in the expression of lipid metabolism, apoptosis and oxidative stress genes. The increased LD buildup in T2D β-cells was accompanied by inhibition of nuclear translocation of TFEB, a master regulator of autophagy and by down-regulation of lysosomal biomarker LAMP2. To investigate whether LD accumulation and autophagy were influenced by diabetic conditions, we used rat INS-1 cells to model the effects of hyperglycaemia and hyperlipidaemia on autophagy and metabolic gene expression. Consistent with human tissue, both LD formation and PLIN2 expression were enhanced in INS-1 cells under hyperglycaemia, whereas TFEB activation and autophagy gene expression were significantly reduced. Collectively, these results suggest that lipid clearance and overall homeostasis is markedly disrupted in β-cells under hyperglycaemic conditions and interventions ameliorating lipid clearance could be beneficial in reducing functional impairments in islets caused by glucolipotoxicity.
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Affiliation(s)
- Jeff Ji
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | | | - Armen Khatchadourian
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Jason Patapas
- Department of Surgery, McGill University, Montreal, QC, Canada
| | - Julia Makhlin
- Department of Surgery, McGill University, Montreal, QC, Canada
| | | | - Dusica Maysinger
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
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Altered expression of PGC-1α and PDX1 and their methylation status are associated with fetal glucose metabolism in gestational diabetes mellitus. Biochem Biophys Res Commun 2018; 501:300-306. [PMID: 29730292 DOI: 10.1016/j.bbrc.2018.05.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 05/02/2018] [Indexed: 11/23/2022]
Abstract
PURPOSE To investigate the effect of gestational diabetes mellitus (GDM) on the expression and methylation of PGC-1α and PDX1 in placenta and their effects on fetal glucose metabolism. METHODS 20 cases of full-term placenta without pregnancy complications and umbilical cord abnormalities and 20 cases of GDM group were collected. DNA and RNA were isolated from samples of tissue collected from the fetal side of the placenta immediately after delivery. DNA methylation was quantified at 7 CpG sites within the PGC-1α and PDX1 genes using PCR amplification of bisulfite treated DNA and subsequent DNA sequencing. PGC-1α and PDX1 mRNA levels were measured by reverse transcription-quantitative PCR (RT-qPCR). Meanwhile, the placental insulin, blood glucose and HbA1c levels were determined. RESULTS The fetus birth weight and placental weight in GDM group were significantly higher than those in control group (P < 0.05). Insulin, HbA1c and blood glucose levels in GDM group were significantly higher than those in control group (P < 0.01). Insulin content was positively correlated with newborn birth weight and placental weight while HbA1c and blood glucose were positively correlated with insulin concentration (r = 0.92, P < 0.01, r = 0.85, P < 0.01). The levels of PGC-1α and PDX1 mRNA were lower in the GDM group compared to the control group. The methylation level of PGC-1α gene was higher in the GDM group compared to the control group (P < 0.05). Blood glucose was negatively correlated with the expression of PGC-1α and PDX1 mRNA in the placenta (r = -0.42, P < 0.01, r = -0.49, P < 0.01). CONCLUSION The changes of epigenetic modification of PGC-1α gene in pregnant women with gestational diabetes mellitus may be a mechanism of abnormal glucose metabolism in offspring.
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Vandenbeek R, Khan NP, Estall JL. Linking Metabolic Disease With the PGC-1α Gly482Ser Polymorphism. Endocrinology 2018; 159:853-865. [PMID: 29186342 DOI: 10.1210/en.2017-00872] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/20/2017] [Indexed: 12/11/2022]
Abstract
Peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) is a highly conserved transcriptional coactivator enriched in metabolically active tissues including liver, adipose, pancreas, and muscle. It plays a role in regulating whole body energy metabolism and its deregulation has been implicated in type 2 diabetes (T2D). A single nucleotide variant of the PPARGC1A gene (rs8192678) is associated with T2D susceptibility, relative risk of obesity and insulin resistance, and lower indices of β cell function. This common polymorphism is within a highly conserved region of the bioactive protein and leads to a single amino acid substitution (glycine 482 to serine). Its prevalence and effects on metabolic parameters appear to vary depending on factors including ethnicity and sex, suggesting important interactions between genetics and cultural/environmental factors and associated disease risk. Interestingly, carriers of the serine allele respond better to some T2D interventions, illustrating the importance of understanding functional impacts of genetic variance on PGC-1α when targeting this pathway for personalized medicine. This review summarizes a growing body of literature surrounding possible links between the PGC-1α Gly482Ser single nucleotide polymorphism and diabetes, with focus on key clinical findings, affected metabolic systems, potential molecular mechanisms, and the influence of geographical or ethnic background on associated risk.
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Affiliation(s)
- Roxanne Vandenbeek
- Institut de recherches cliniques de Montreal, Montreal, Quebec, Canada
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
| | - Naveen P Khan
- Institut de recherches cliniques de Montreal, Montreal, Quebec, Canada
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
| | - Jennifer L Estall
- Institut de recherches cliniques de Montreal, Montreal, Quebec, Canada
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
- Faculty of Medicine, University of Montreal, Montréal, Québec, Canada
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Jouvet N, Estall JL. The pancreas: Bandmaster of glucose homeostasis. Exp Cell Res 2017; 360:19-23. [DOI: 10.1016/j.yexcr.2017.03.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 03/21/2017] [Accepted: 03/23/2017] [Indexed: 01/02/2023]
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Kim SJ, Xiao J, Wan J, Cohen P, Yen K. Mitochondrially derived peptides as novel regulators of metabolism. J Physiol 2017; 595:6613-6621. [PMID: 28574175 DOI: 10.1113/jp274472] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 05/26/2017] [Indexed: 12/22/2022] Open
Abstract
Mitochondrially derived peptides represent a new class of circulating signalling molecules. Humanin, the first member of this class, has been shown to have several metabolic effects such as reducing weight gain and visceral fat and increasing glucose-stimulated insulin release. The discovery of several other new members, such as MOTS-c and SHLP1-6, has further added to this group. These new peptides have also been found to affect metabolism with MOTS-c potently decreasing weight gain in mice on a high-fat diet. This review covers the basic biology of this class of peptides and discusses the relevance to organismal metabolism.
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Affiliation(s)
- Su-Jeong Kim
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Jialin Xiao
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Junxiang Wan
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Pinchas Cohen
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Kelvin Yen
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
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Branco RCS, Camargo RL, Batista TM, Vettorazzi JF, Borck PC, Dos Santos-Silva JCR, Boschero AC, Zoppi CC, Carneiro EM. Protein malnutrition blunts the increment of taurine transporter expression by a high-fat diet and impairs taurine reestablishment of insulin secretion. FASEB J 2017; 31:4078-4087. [PMID: 28572444 DOI: 10.1096/fj.201600326rrr] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 05/15/2017] [Indexed: 12/23/2022]
Abstract
Taurine (Tau) restores β-cell function in obesity; however, its action is lost in malnourished obese rodents. Here, we investigated the mechanisms involved in the lack of effects of Tau in this model. C57BL/6 mice were fed a control diet (CD) (14% protein) or a protein-restricted diet (RD) (6% protein) for 6 wk. Afterward, mice received a high-fat diet (HFD) for 8 wk [CD + HFD (CH) and RD + HFD (RH)] with or without 5% Tau supplementation after weaning on their drinking water [CH + Tau (CHT) and RH + Tau (RHT)]. The HFD increased insulin secretion through mitochondrial metabolism in CH and RH. Tau prevented all those alterations in CHT only. The expression of the taurine transporter (Tau-T), as well as Tau content in pancreatic islets, was increased in CH but had no effect on RH. Protein malnutrition programs β cells and impairs Tau-induced restoration of mitochondrial metabolism and biogenesis. This may be associated with modulation of the expression of Tau-T in pancreatic islets, which may be responsible for the absence of effect of Tau in protein-malnourished obese mice.-Branco, R. C. S., Camargo, R. L., Batista, T. M., Vettorazzi, J. F., Borck, P. C., dos Santos-Silva, J. C. R., Boschero, A. C., Zoppi, C. C., Carneiro, E. M. Protein malnutrition blunts the increment of taurine transporter expression by a high-fat diet and impairs taurine reestablishment of insulin secretion.
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Affiliation(s)
- Renato Chaves Souto Branco
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Rafael Ludemann Camargo
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Thiago Martins Batista
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Jean Franciesco Vettorazzi
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Patrícia Cristine Borck
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | | | - Antonio Carlos Boschero
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Cláudio Cesar Zoppi
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Everardo Magalhães Carneiro
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
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Interaction effect of PGC-1α rs10517030 variants and energy intake in the risk of type 2 diabetes in middle-aged adults. Eur J Clin Nutr 2017; 71:1442-1448. [DOI: 10.1038/ejcn.2017.68] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 01/29/2017] [Accepted: 03/19/2017] [Indexed: 12/22/2022]
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Sun D, Yang F. Metformin improves cardiac function in mice with heart failure after myocardial infarction by regulating mitochondrial energy metabolism. Biochem Biophys Res Commun 2017; 486:329-335. [PMID: 28302481 DOI: 10.1016/j.bbrc.2017.03.036] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 03/11/2017] [Indexed: 12/20/2022]
Abstract
To investigate whether metformin can improve the cardiac function through improving the mitochondrial function in model of heart failure after myocardial infarction. Male C57/BL6 mice aged about 8 weeks were selected and the anterior descending branch was ligatured to establish the heart failure model after myocardial infarction. The cardiac function was evaluated via ultrasound after 3 days to determine the modeling was successful, and the mice were randomly divided into two groups. Saline group (Saline) received the intragastric administration of normal saline for 4 weeks, and metformin group (Met) received the intragastric administration of metformin for 4 weeks. At the same time, Shame group (Sham) was set up. Changes in cardiac function in mice were detected at 4 weeks after operation. Hearts were taken from mice after 4 weeks, and cell apoptosis in myocardial tissue was detected using TUNEL method; fresh mitochondria were taken and changes in oxygen consumption rate (OCR) and respiratory control rate (RCR) of mitochondria in each group were detected using bio-energy metabolism tester, and change in mitochondrial membrane potential (MMP) of myocardial tissue was detected via JC-1 staining; the expressions and changes in Bcl-2, Bax, Sirt3, PGC-1α and acetylated PGC-1α in myocardial tissue were detected by Western blot. RT-PCR was used to detect mRNA levels in Sirt3 in myocardial tissues. Metformin improved the systolic function of heart failure model rats after myocardial infarction and reduced the apoptosis of myocardial cells after myocardial infarction. Myocardial mitochondrial respiratory function and membrane potential were decreased after myocardial infarction, and metformin treatment significantly improved the mitochondrial respiratory function and mitochondrial membrane potential; Metformin up-regulated the expression of Sirt3 and the activity of PGC-1α in myocardial tissue of heart failure after myocardial infarction. Metformin decreases the acetylation level of PGC-1α through up-regulating Sirt3, mitigates the damage to mitochondrial membrane potential of model of heart failure after myocardial infarction and improves the respiratory function of mitochondria, thus improving the cardiac function of mice.
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Affiliation(s)
- Dan Sun
- Department of Geriatrics, General Hospital of Daqing Oil Field, Daqing City, China.
| | - Fei Yang
- Department of Geriatrics, General Hospital of Daqing Oil Field, Daqing City, China
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Sfera A, Osorio C, Inderias LA, Parker V, Price AI, Cummings M. The Obesity-Impulsivity Axis: Potential Metabolic Interventions in Chronic Psychiatric Patients. Front Psychiatry 2017; 8:20. [PMID: 28243210 PMCID: PMC5303716 DOI: 10.3389/fpsyt.2017.00020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 01/25/2017] [Indexed: 12/20/2022] Open
Abstract
Pathological impulsivity is encountered in a broad range of psychiatric conditions and is thought to be a risk factor for aggression directed against oneself or others. Recently, a strong association was found between impulsivity and obesity which may explain the high prevalence of metabolic disorders in individuals with mental illness even in the absence of exposure to psychotropic drugs. As the overlapping neurobiology of impulsivity and obesity is being unraveled, the question asked louder and louder is whether they should be treated concomitantly. The treatment of obesity and metabolic dysregulations in chronic psychiatric patients is currently underutilized and often initiated late, making correction more difficult to achieve. Addressing obesity and metabolic dysfunction in a preventive manner may not only lower morbidity and mortality but also the excessive impulsivity, decreasing the risk for aggression. In this review, we take a look beyond psychopharmacological interventions and discuss dietary and physical therapy approaches.
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Affiliation(s)
- Adonis Sfera
- Patton State Hospital, Psychiatry, Patton, CA, USA
| | | | | | | | - Amy I. Price
- Oxford University, Evidence Based Medicine, Oxford, UK
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Cataldo LR, Mizgier ML, Bravo Sagua R, Jaña F, Cárdenas C, Llanos P, Busso D, Olmos P, Galgani JE, Santos JL, Cortés VA. Prolonged Activation of the Htr2b Serotonin Receptor Impairs Glucose Stimulated Insulin Secretion and Mitochondrial Function in MIN6 Cells. PLoS One 2017; 12:e0170213. [PMID: 28129327 PMCID: PMC5271329 DOI: 10.1371/journal.pone.0170213] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 01/02/2017] [Indexed: 11/23/2022] Open
Abstract
Aims Pancreatic β-cells synthesize and release serotonin (5 hydroxytryptamine, 5HT); however, the role of 5HT receptors on glucose stimulated insulin secretion (GSIS) and the mechanisms mediating this function is not fully understood. The aims of this study were to determine the expression profile of 5HT receptors in murine MIN6 β-cells and to examine the effects of pharmacological activation of 5HT receptor Htr2b on GSIS and mitochondrial function. Materials and Methods mRNA levels of 5HT receptors in MIN6 cells were quantified by RT qPCR. GSIS was assessed in MIN6 cells in response to global serotonergic activation with 5HT and pharmacological Htr2b activation or inhibition with BW723C86 or SB204741, respectively. In response to Htr2b activation also was evaluated the mRNA and protein levels of PGC1α and PPARy by RT-qPCR and western blotting and mitochondrial function by oxygen consumption rate (OCR) and ATP cellular content. Results We found that mRNA levels of most 5HT receptors were either very low or undetectable in MIN6 cells. By contrast, Htr2b mRNA was present at moderate levels in these cells. Preincubation (6 h) of MIN6 cells with 5HT or BW723C86 reduced GSIS and the effect of 5HT was prevented by SB204741. Preincubation with BW723C86 increased PGC1α and PPARy mRNA and protein levels and decreased mitochondrial respiration and ATP content in MIN6 cells. Conclusions Our results indicate that prolonged Htr2b activation in murine β-cells decreases glucose-stimulated insulin secretion and mitochondrial activity by mechanisms likely dependent on enhanced PGC1α/PPARy expression.
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Affiliation(s)
- Luis Rodrigo Cataldo
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María L. Mizgier
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Roberto Bravo Sagua
- Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago, Chile
| | - Fabián Jaña
- Anatomy and Developmental Biology Program, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - César Cárdenas
- Anatomy and Developmental Biology Program, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
- Buck Institute for Research on Aging, Novato, CA, United States of America
| | - Paola Llanos
- Institute for Research in Dental Sciences, School of Odontology, University of Chile, Santiago, Chile
| | - Dolores Busso
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo Olmos
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José E. Galgani
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- UDA-Health Sciences, Nutrition and Dietetic Program, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José L. Santos
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Víctor A. Cortés
- Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- * E-mail:
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Zhang D, Wang F, Lal N, Chiu APL, Wan A, Jia J, Bierende D, Flibotte S, Sinha S, Asadi A, Hu X, Taghizadeh F, Pulinilkunnil T, Nislow C, Vlodavsky I, Johnson JD, Kieffer TJ, Hussein B, Rodrigues B. Heparanase Overexpression Induces Glucagon Resistance and Protects Animals From Chemically Induced Diabetes. Diabetes 2017; 66:45-57. [PMID: 27999107 DOI: 10.2337/db16-0761] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 10/01/2016] [Indexed: 11/13/2022]
Abstract
Heparanase, a protein with enzymatic and nonenzymatic properties, contributes toward disease progression and prevention. In the current study, a fortuitous observation in transgenic mice globally overexpressing heparanase (hep-tg) was the discovery of improved glucose homeostasis. We examined the mechanisms that contribute toward this improved glucose metabolism. Heparanase overexpression was associated with enhanced glucose-stimulated insulin secretion and hyperglucagonemia, in addition to changes in islet composition and structure. Strikingly, the pancreatic islet transcriptome was greatly altered in hep-tg mice, with >2,000 genes differentially expressed versus control. The upregulated genes were enriched for diverse functions including cell death regulation, extracellular matrix component synthesis, and pancreatic hormone production. The downregulated genes were tightly linked to regulation of the cell cycle. In response to multiple low-dose streptozotocin (STZ), hep-tg animals developed less severe hyperglycemia compared with wild-type, an effect likely related to their β-cells being more functionally efficient. In animals given a single high dose of STZ causing severe and rapid development of hyperglycemia related to the catastrophic loss of insulin, hep-tg mice continued to have significantly lower blood glucose. In these mice, protective pathways were uncovered for managing hyperglycemia and include augmentation of fibroblast growth factor 21 and glucagon-like peptide 1. This study uncovers the opportunity to use properties of heparanase in management of diabetes.
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Affiliation(s)
- Dahai Zhang
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Fulong Wang
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Nathaniel Lal
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Amy Pei-Ling Chiu
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrea Wan
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Jocelyn Jia
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Denise Bierende
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephane Flibotte
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Sunita Sinha
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Ali Asadi
- Department of Cellular & Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Xiaoke Hu
- Department of Cellular & Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Farnaz Taghizadeh
- Department of Cellular & Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Thomas Pulinilkunnil
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, Dalhousie University, Saint John, New Brunswick, Canada
| | - Corey Nislow
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Israel Vlodavsky
- Rappaport Faculty of Medicine, Cancer and Vascular Biology Research Center, Technion, Haifa, Israel
| | - James D Johnson
- Department of Cellular & Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Timothy J Kieffer
- Department of Cellular & Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Bahira Hussein
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian Rodrigues
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
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Martinez B, Soñanez-Organis JG, Godoy-Lugo JA, Horin LJ, Crocker DE, Ortiz RM. Thyroid hormone-stimulated increases in PGC-1α and UCP2 promote life history-specific endocrine changes and maintain a lipid-based metabolism. Am J Physiol Regul Integr Comp Physiol 2016; 312:R189-R196. [PMID: 27903512 DOI: 10.1152/ajpregu.00395.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 10/31/2016] [Accepted: 11/18/2016] [Indexed: 12/12/2022]
Abstract
Thyroid hormones (THs) regulate metabolism, but are typically suppressed during times of stressful physiological conditions, including fasting. Interestingly, prolonged fasting in northern elephant seal pups is associated with reliance on a lipid-based metabolism and increased levels of circulating THs that are partially attributed to active secretion as opposed to reduced clearance. This apparent paradox is coupled with complementary increases in cellular TH-mediated activity, suggesting that in mammals naturally adapted to prolonged fasting, THs are necessary to support metabolism. However, the functional relevance of this physiological paradox has remained largely unexplored, especially as it relates to the regulation of lipids. To address the hypothesis that TSH-mediated increase in THs contributes to lipid metabolism, we infused early and late-fasted pups with TSH and measured several key genes in adipose and muscle, and plasma hormones associated with regulation of lipid metabolism. TSH infusion increased the mRNA expressions of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) more than 6.5-fold at 60 min in muscle, and expression of uncoupling protein 2 (UCP2) more than 27-fold during the early fast at 60 min, in adipose. Additionally, during the late fast period, the protein content of adipose CD36 increased 1.1-fold, and plasma nonesterified fatty acid (NEFA) concentrations increased 25% at 120 min, with NEFA levels returning to baseline after 24 h. We show that the TSH-induced increases in THs in fasting pups are functional and likely contribute to the maintenance of a lipid-based metabolism.
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Affiliation(s)
- Bridget Martinez
- Molecular and Cellular Biology, University of California Merced, Merced, California;
| | - José G Soñanez-Organis
- Departamento de Ciencias Químico Biológicas y Agropecuarias, Universidad de Sonora, Francisco Villa, Navojoa Sonora, México
| | - José Arquimides Godoy-Lugo
- Departamento de Ciencias Químico Biológicas y Agropecuarias, Universidad de Sonora, Francisco Villa, Navojoa Sonora, México
| | - Lillian J Horin
- W. M. Keck Science Department, Pitzer College, Claremont, California; and
| | - Daniel E Crocker
- Department of Biology, Sonoma State University, Rohnert Park, California
| | - Rudy M Ortiz
- Molecular and Cellular Biology, University of California Merced, Merced, California
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