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Gelbach PE, Zheng D, Fraser SE, White KL, Graham NA, Finley SD. Kinetic and data-driven modeling of pancreatic β-cell central carbon metabolism and insulin secretion. PLoS Comput Biol 2022; 18:e1010555. [PMID: 36251711 PMCID: PMC9612825 DOI: 10.1371/journal.pcbi.1010555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 10/27/2022] [Accepted: 09/08/2022] [Indexed: 11/06/2022] Open
Abstract
Pancreatic β-cells respond to increased extracellular glucose levels by initiating a metabolic shift. That change in metabolism is part of the process of glucose-stimulated insulin secretion and is of particular interest in the context of diabetes. However, we do not fully understand how the coordinated changes in metabolic pathways and metabolite products influence insulin secretion. In this work, we apply systems biology approaches to develop a detailed kinetic model of the intracellular central carbon metabolic pathways in pancreatic β-cells upon stimulation with high levels of glucose. The model is calibrated to published metabolomics datasets for the INS1 823/13 cell line, accurately capturing the measured metabolite fold-changes. We first employed the calibrated mechanistic model to estimate the stimulated cell's fluxome. We then used the predicted network fluxes in a data-driven approach to build a partial least squares regression model. By developing the combined kinetic and data-driven modeling framework, we gain insights into the link between β-cell metabolism and glucose-stimulated insulin secretion. The combined modeling framework was used to predict the effects of common anti-diabetic pharmacological interventions on metabolite levels, flux through the metabolic network, and insulin secretion. Our simulations reveal targets that can be modulated to enhance insulin secretion. The model is a promising tool to contextualize and extend the usefulness of metabolomics data and to predict dynamics and metabolite levels that are difficult to measure in vitro. In addition, the modeling framework can be applied to identify, explain, and assess novel and clinically-relevant interventions that may be particularly valuable in diabetes treatment.
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Affiliation(s)
- Patrick E. Gelbach
- Department of Biomedical Engineering, USC, Los Angeles, California, United States of America
| | - Dongqing Zheng
- Mork Family Department of Chemical Engineering and Materials Science, USC, Los Angeles, California, United States of America
| | - Scott E. Fraser
- Translational Imaging Center, University of Southern California, Los Angeles, California, United States of America
| | - Kate L. White
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center, USC, Los Angeles, California, United States of America
| | - Nicholas A. Graham
- Mork Family Department of Chemical Engineering and Materials Science, USC, Los Angeles, California, United States of America
| | - Stacey D. Finley
- Department of Biomedical Engineering, USC, Los Angeles, California, United States of America
- Mork Family Department of Chemical Engineering and Materials Science, USC, Los Angeles, California, United States of America
- Department of Quantitative and Computational Biology, USC, Los Angeles, California, United States of America
- * E-mail:
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2
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San Martín A, Arce-Molina R, Aburto C, Baeza-Lehnert F, Barros LF, Contreras-Baeza Y, Pinilla A, Ruminot I, Rauseo D, Sandoval PY. Visualizing physiological parameters in cells and tissues using genetically encoded indicators for metabolites. Free Radic Biol Med 2022; 182:34-58. [PMID: 35183660 DOI: 10.1016/j.freeradbiomed.2022.02.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 02/07/2023]
Abstract
The study of metabolism is undergoing a renaissance. Since the year 2002, over 50 genetically-encoded fluorescent indicators (GEFIs) have been introduced, capable of monitoring metabolites with high spatial/temporal resolution using fluorescence microscopy. Indicators are fusion proteins that change their fluorescence upon binding a specific metabolite. There are indicators for sugars, monocarboxylates, Krebs cycle intermediates, amino acids, cofactors, and energy nucleotides. They permit monitoring relative levels, concentrations, and fluxes in living systems. At a minimum they report relative levels and, in some cases, absolute concentrations may be obtained by performing ad hoc calibration protocols. Proper data collection, processing, and interpretation are critical to take full advantage of these new tools. This review offers a survey of the metabolic indicators that have been validated in mammalian systems. Minimally invasive, these indicators have been instrumental for the purposes of confirmation, rebuttal and discovery. We envision that this powerful technology will foster metabolic physiology.
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Affiliation(s)
- A San Martín
- Centro de Estudios Científicos (CECs), Valdivia, Chile.
| | - R Arce-Molina
- Centro de Estudios Científicos (CECs), Valdivia, Chile
| | - C Aburto
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Universidad Austral de Chile, Valdivia, Chile
| | | | - L F Barros
- Centro de Estudios Científicos (CECs), Valdivia, Chile
| | - Y Contreras-Baeza
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Universidad Austral de Chile, Valdivia, Chile
| | - A Pinilla
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Universidad Austral de Chile, Valdivia, Chile
| | - I Ruminot
- Centro de Estudios Científicos (CECs), Valdivia, Chile
| | - D Rauseo
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Universidad Austral de Chile, Valdivia, Chile
| | - P Y Sandoval
- Centro de Estudios Científicos (CECs), Valdivia, Chile
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Mohajeri M, Horriatkhah E, Mohajery R. The effect of glutamine supplementation on serum levels of some inflammatory factors, oxidative stress, and appetite in COVID-19 patients: a case-control study. Inflammopharmacology 2021; 29:1769-1776. [PMID: 34709541 PMCID: PMC8552429 DOI: 10.1007/s10787-021-00881-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 09/16/2021] [Indexed: 01/12/2023]
Abstract
Background Malnutrition is seen in COVID-19 patients, and reducing malnutrition with appropriate therapies may improve these patients' health. This case–control study aimed to assess and compare serum levels of some inflammatory factors, oxidative stress, and appetite in COVID-19 patients with respiratory infections that receive glutamine treatment with a control group. Methods In this study, patients who consented to use glutamine were considered as the case group and other patients who did not use glutamine were considered as a control group. Two hundred twenty-two COVID-19 patients (51.2 ± 6.7) using l-Glutamine and 230 COVID-19 patients (51.3 ± 8.2) with similar age, gender, and clinical status, as the control group, were included in the study. For 5 days, the case group consumed 10 g of glutamine supplement three times per day. At the end of the 5 days, blood samples were taken again to test for serum levels of IL1β, tumor necrosis factor-α, malondialdehyde, and total antioxidant capacity, then all data were analyzed. Results Serum levels of β-1 interleukin, tumor necrosis factor-α and hs-CRP were significantly reduced with five days of glutamine supplementation (p < 0.05), and patients’ appetite during 5 days of glutamine supplementation compared with the control group had a significant increase (p < 0.05). Conclusion Glutamine supplementation in COVID-19 patients with respiratory infection significantly reduces serum levels of interleukin-1 β, hs-CRP, and tumor necrosis factor-α and significantly increases appetite, so glutamine supplementation may be useful for COVID-19 patients in the hospital.
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Affiliation(s)
- Mahsa Mohajeri
- Digestive Disease Research Center, Ardabil University of Medical Sciences, Ardabil, Iran.
- Academic Center for Education, Culture and Research, Ardabil, Iran.
| | - Ehsan Horriatkhah
- Digestive Disease Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
- Tehran University of Medical Science, Tehran, Iran
| | - Reza Mohajery
- Energy Management Research Center, University of Mohaghegh Ardabili, Ardabil, Iran
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Shen Y, Zhang Y, Li W, Chen K, Xiang M, Ma H. Glutamine metabolism: from proliferating cells to cardiomyocytes. Metabolism 2021; 121:154778. [PMID: 33901502 DOI: 10.1016/j.metabol.2021.154778] [Citation(s) in RCA: 9] [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: 01/18/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023]
Abstract
Glutamine is a major energy source for rapidly dividing cells, such as hematopoietic stem cells and cancer cells. Reliance on glutamine is therefore regarded as a metabolic hallmark of proliferating cells. Moreover, reprogramming glutamine metabolism by various factors, including tissue type, microenvironment, pro-oncogenes, and tumor suppressor genes, can facilitate stem cell fate decisions, tumor recurrence, and drug resistance. However, the significance of glutamine metabolism in cardiomyocytes, an end-differentiated cell type, is not fully understood. Existing evidence suggests important roles of glutamine metabolism in the development of cardiovascular diseases. In this review, we have focused on glutaminolysis and its regulatory network in proliferating cells. We have summarized current findings about the role of glutamine utilization in cardiomyocytes and have discussed possibilities of targeting glutamine metabolism for the treatment of cardiovascular diseases.
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Affiliation(s)
- Yimin Shen
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China
| | - Yuhao Zhang
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China
| | - Wudi Li
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China
| | - Kaijie Chen
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China
| | - Meixiang Xiang
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China.
| | - Hong Ma
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China.
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Hira T, Trakooncharoenvit A, Taguchi H, Hara H. Improvement of Glucose Tolerance by Food Factors Having Glucagon-Like Peptide-1 Releasing Activity. Int J Mol Sci 2021; 22:6623. [PMID: 34205659 PMCID: PMC8235588 DOI: 10.3390/ijms22126623] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/17/2021] [Accepted: 06/17/2021] [Indexed: 12/14/2022] Open
Abstract
Glucagon-like peptide-1 (GLP-1) is a gastrointestinal hormone released from enteroendocrine L cells in response to meal ingestion. GLP-1 receptor agonists and GLP-1 enhancers have been clinically employed to treat diabetes owing to their glucose-dependent insulin-releasing activity. The release of GLP-1 is primarily stimulated by macronutrients such as glucose and fatty acids, which are nutritionally indispensable; however, excessive intake of sugar and fat is responsible for the development of obesity and diabetes. Therefore, GLP-1 releasing food factors, such as dietary peptides and non-nutrients, are deemed desirable for improving glucose tolerance. Human and animal studies have revealed that dietary proteins/peptides have a potent effect on stimulating GLP-1 secretion. Studies in enteroendocrine cell models have shown that dietary peptides, amino acids, and phytochemicals, such as quercetin, can directly stimulate GLP-1 secretion. In our animal experiments, these food factors improved glucose metabolism and increased GLP-1 secretion. Furthermore, some dietary peptides not only stimulated GLP-1 secretion but also reduced plasma peptidase activity, which is responsible for GLP-1 inactivation. Herein, we review the relationship between GLP-1 and food factors, especially dietary peptides and flavonoids. Accordingly, utilization of food factors with GLP-1-releasing/enhancing activity is a promising strategy for preventing and treating obesity and diabetes.
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Affiliation(s)
- Tohru Hira
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
- Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan;
- School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan;
| | | | - Hayate Taguchi
- School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan;
| | - Hiroshi Hara
- Department of Food Science and Human Nutrition, Fuji Women’s University, Ishikari-shi 061-320, Japan;
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The role of gut microbiota and amino metabolism in the effects of improvement of islet β-cell function after modified jejunoileal bypass. Sci Rep 2021; 11:4809. [PMID: 33637880 PMCID: PMC7910448 DOI: 10.1038/s41598-021-84355-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 02/15/2021] [Indexed: 12/23/2022] Open
Abstract
The change in gut microbiota is an important mechanism of the amelioration of type 2 diabetes mellitus (T2DM) after bariatric surgery. Here, we observe that the modified jejunoileal bypass effectively decreases body weight gain, fasting blood glucose, and lipids level in serum; additionally, islet β-cell function, glucose tolerance, and insulin resistance were markedly ameliorated. The hypoglycemic effect and the improvement in islet β-cell function depend on the changes in gut microbiota structure. modified jejunoileal bypass increases the abundance of gut Escherichia coli and Ruminococcus gnavus and the levels of serum glycine, histidine, and glutamine in T2DM rats; and decreases the abundance of Prevotella copri and the levels of serum branched chain amino acids, which are significantly related to the improvement of islet β-cell function in T2DM rats. Our results suggest that amino acid metabolism may contribute to the islet β-cell function in T2DM rats after modified jejunoileal bypass and that improving gut microbiota composition is a potential therapeutic strategy for T2DM.
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Wang Y, Alkhalidy H, Liu D. The Emerging Role of Polyphenols in the Management of Type 2 Diabetes. Molecules 2021; 26:molecules26030703. [PMID: 33572808 PMCID: PMC7866283 DOI: 10.3390/molecules26030703] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 12/12/2022] Open
Abstract
Type 2 diabetes (T2D) is a fast-increasing health problem globally, and it results from insulin resistance and pancreatic β-cell dysfunction. The gastrointestinal (GI) tract is recognized as one of the major regulatory organs of glucose homeostasis that involves multiple gut hormones and microbiota. Notably, the incretin hormone glucagon-like peptide-1 (GLP-1) secreted from enteroendocrine L-cells plays a pivotal role in maintaining glucose homeostasis via eliciting pleiotropic effects, which are largely mediated via its receptor. Thus, targeting the GLP-1 signaling system is a highly attractive therapeutic strategy to treatment T2D. Polyphenols, the secondary metabolites from plants, have drawn considerable attention because of their numerous health benefits, including potential anti-diabetic effects. Although the major targets and locations for the polyphenolic compounds to exert the anti-diabetic action are still unclear, the first organ that is exposed to these compounds is the GI tract in which polyphenols could modulate enzymes and hormones. Indeed, emerging evidence has shown that polyphenols can stimulate GLP-1 secretion, indicating that these natural compounds might exert metabolic action at least partially mediated by GLP-1. This review provides an overview of nutritional regulation of GLP-1 secretion and summarizes recent studies on the roles of polyphenols in GLP-1 secretion and degradation as it relates to metabolic homeostasis. In addition, the effects of polyphenols on microbiota and microbial metabolites that could indirectly modulate GLP-1 secretion are also discussed.
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Affiliation(s)
- Yao Wang
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA;
| | - Hana Alkhalidy
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, Irbid 22110, Jordan;
| | - Dongmin Liu
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA;
- Correspondence: ; Tel.: +1-540-231-3402; Fax: +1-540-231-3916
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Tavakoli-Rouzbehani OM, Maleki V, Shadnoush M, Taheri E, Alizadeh M. A comprehensive insight into potential roles of Nigella sativa on diseases by targeting AMP-activated protein kinase: a review. ACTA ACUST UNITED AC 2020; 28:779-787. [PMID: 33140312 DOI: 10.1007/s40199-020-00376-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 10/23/2020] [Indexed: 12/17/2022]
Abstract
OBJECTIVES Nigella sativa (NS) is a known medicinal herb with numerous therapeutic effects such as antidiabetic, anti-proliferative, anti-inflammatory, and anti-cancer activities. It has been indicated that NS can regulate cellular metabolism by adjusting transduction signaling pathways. Adenosine monophosphate-activated protein kinase (AMPK) is one of the main physiological processes, such as energy hemostasis, cellular metabolism, and autophagy regulators. Herb-derived medicines have always been considered as one of the main AMPK activators, and surprisingly recent data has demonstrated that it can be a target for NS and its derivatives. EVIDENCE ACQUISITION The literature search was conducted in PubMed, SCOPUS, Embase, ProQuest, and Google Scholar electronic resources. Published articles up to September 2020 were considered, and those of which investigated Nigella sativa effects on the AMPK pathway after meeting the inclusion criteria were included. RESULTS The search was performed on several online databases such as PubMed, Scopus, Embase, ProQuest, and Google Scholar from inception until January 2020. Among the initial search, 245 studies were found. After removing duplicated data and meeting the inclusion criteria, only 14 studies were selected. They included the effects of NS and its bioactive compounds as anti-hyperglycemic (n = 5), on liver function (n = 4), cancers (n = 3), and on Neuroinflammation and Atherosclerosis (n = 2). Most of the included studies are animals or in-vitro investigations. CONCLUSION In this review, we discuss the latest findings on the molecular mechanism of NS effecting the AMPK signaling pathway. We also focus on the therapeutic effects of NS, including the prevention and treatment of metabolic and pro-inflammatory disease by targeting the AMPK pathway.
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Affiliation(s)
| | - Vahid Maleki
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Mahdi Shadnoush
- Department of Clinical Nutrition, Faculty of Nutrition & Food Technology, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Ehsaneh Taheri
- Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Alizadeh
- Nutrition Research Center, Faculty of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
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Jafari-Vayghan H, Varshosaz P, Hajizadeh-Sharafabad F, Razmi HR, Amirpour M, Tavakoli-Rouzbehani OM, Alizadeh M, Maleki V. A comprehensive insight into the effect of glutamine supplementation on metabolic variables in diabetes mellitus: a systematic review. Nutr Metab (Lond) 2020; 17:80. [PMID: 32983244 PMCID: PMC7517657 DOI: 10.1186/s12986-020-00503-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 09/10/2020] [Indexed: 12/14/2022] Open
Abstract
Diabetes mellitus is one of the most important threats to human health in the twenty-first century.
The use of complementary and alternative medicine to prevent, control, and reduce the complications of diabetes mellitus is increasing at present. Glutamine amino acid is known as a functional food.
The purpose of this systematic review is to determine the potential role of glutamine supplementation on metabolic variables in diabetes mellitus. For this review, PubMed, SCOPUS, Embase, ProQuest, and Google Scholar databases were searched from inception through April 2020. All clinical trial and animal studies assessing the effects of glutamine on diabetes mellitus were eligible for inclusion. 19 studies of 1482 articles met the inclusion criteria. Of the 19 studies, nine studies reported a significant increase in serum GLP-1 levels. Also, eight studies showed reducing in serum levels of fasting blood sugar, four studies reducing in postprandial blood sugar, and triglyceride after glutamine supplementation. Although glutamine resulted in a significant increase in insulin production in seven studies, the findings on Hb-A1c levels were inconclusive. In addition to, despite of the results was promising for the effects of glutamine on weight changes, oxidative stress, and inflammation, more precise clinical trials are needed to obtain more accurate results. In conclusion, glutamine supplementation could improve glycemic control and levels of incretins (such as GLP-1 and GIP) in diabetes mellitus. However, more studies are needed for future studies.
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Affiliation(s)
- Hamed Jafari-Vayghan
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.,Faculty of Health, Arak University of Medical Sciences, Arak, Iran
| | - Parisa Varshosaz
- Departments of Chemistry and Biochemistry, and Biology and Biomolecular Sciences Program, Laurentian University, Sudbury, ON Canada
| | - Fatemeh Hajizadeh-Sharafabad
- Department of Clinical Nutrition, Faculty of Nutrition and Food Science, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Reza Razmi
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahdi Amirpour
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mohammad Alizadeh
- Nutrition Research Center, Faculty of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Vahid Maleki
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
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Amino Acids in Health and Endocrine Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1265:97-109. [PMID: 32761572 DOI: 10.1007/978-3-030-45328-2_6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
Dietary amino acids play an important role in maintaining health. Branched chain amino acids can adversely increase blood pressure whereas arginine and citrulline can reduce it. D-amino acids play important roles in several cell types including testis, the nervous system and adrenal glands. Several amino acids also can have dramatic effects on diabetes; branched chain amino acids, phenylalanine and tyrosine have been implicated while others, namely arginine and citrulline can improve outcomes. Leucine has been shown to play important roles in muscle primarily through the mTOR pathway though this effect does not translate across every population. Glutamine, arginine and D-aspartate also exert their muscle effects through mTOR. Relationships between amino acids and endocrine function include that of glucocorticoids, thyroid function, glucagon-like peptide 1 (GLP-1), ghrelin, insulin-like growth factor-1 (IGF-1) and leptin. Leucine, for example, can alleviate the effect of dexamethasone on muscle protein accretion. Interestingly, amino acid transporters play an important role in thyroid function. Several amino acids have been shown to increase GLP-1 levels in non-diabetics when administered orally. Similarly, several amino acids increase ghrelin levels in different species while cysteine can decrease it in mice. There is evidence to suggest that the arginine/NO pathway may be involved in modulating some of the effects of ghrelin on cells. In regard to IGF-1, branched chain amino acids can increase levels in adults while tryptophan and phenylalanine have been shown to increase levels in infants. Finally, leptin levels can be elevated by branched chain amino acids while restricting leucine in high fat diets can increase leptin sensitivity.
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11
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Courtney CM, Shyr ZA, Yan Z, Onufer EJ, Steinberger AE, Tecos ME, Barron LK, Guo J, Remedi MS, Warner BW. Alterations in pancreatic islet cell function in response to small bowel resection. Am J Physiol Gastrointest Liver Physiol 2020; 319:G36-G42. [PMID: 32463335 PMCID: PMC7468758 DOI: 10.1152/ajpgi.00282.2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
After 50% proximal small bowel resection (SBR) in mice, we have demonstrated hepatic steatosis, impaired glucose metabolism without insulin resistance, and increased pancreatic islet area. We sought to determine the consequences of SBR on pancreatic β-cell morphology, proliferation, and expression of a key regulatory hormone, glucagon-like peptide-1 (GLP-1). C57BL/6 mice underwent 50% SBR or sham operation. At 10 wk, pancreatic insulin content and secretion was measured by ELISA. Immunohistochemistry was performed to determine structural alterations in pancreatic α-and β-cells. Western blot analysis was used to measure GLP-1R expression, and immunoassay was used to measure plasma insulin and GLP-1. Experiments were repeated by administering a GLP-1 agonist (exendin-4) to a cohort of mice following SBR. After SBR, there was pancreatic islet hypertrophy and impaired glucose tolerance. The proportion of α and β cells was not grossly altered. Whole pancreas and pancreatic islet insulin content was not significantly different; however, SBR mice demonstrated decreased insulin secretion in both static incubation and islet perfusion experiments. The expression of pancreatic GLP-1R was decreased approximately twofold after SBR, compared with sham and serum GLP-1, was decreased. These metabolic derangements were mitigated after administration of the GLP-1 agonist. Following massive SBR, there is significant hypertrophy of pancreatic islet cells with morphologically intact α- and β-cells. Significantly reduced pancreatic insulin release in both static and dynamic conditions demonstrate a perturbed second phase of insulin secretion. GLP-1 is a key mediator of this amplification pathway. Decreased expression of serum GLP-1 and pancreatic GLP-1R in face of no change in insulin content presents a novel pathway for enteropancreatic glucose regulation following SBR.NEW & NOTEWORTHY Metabolic changes occur following intestinal resection; however, the effects on pancreatic function are unknown. Prior studies have demonstrated that glucagon-like protein-1 (GLP-1) signaling is a crucial player in the improved insulin sensitivity after bariatric surgery. In this study, we explore the effect of massive small bowel resection on gut hormone physiology and provide novel insights into the enteropancreatic axis.
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Affiliation(s)
- Cathleen M. Courtney
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
| | - Zeenat A. Shyr
- 2Division of Endocrinology, Metabolism, and Lipid Research, Washington University in St. Louis, Missouri
| | - Zihan Yan
- 2Division of Endocrinology, Metabolism, and Lipid Research, Washington University in St. Louis, Missouri
| | - Emily Jean Onufer
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
| | - Allie E. Steinberger
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
| | - Maria E. Tecos
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
| | - Lauren K. Barron
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
| | - Jun Guo
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
| | - Maria S. Remedi
- 2Division of Endocrinology, Metabolism, and Lipid Research, Washington University in St. Louis, Missouri
| | - Brad W. Warner
- 1Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University School of Medicine, St. Louis, Missouri
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12
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Jeong JW, Kim M, Lee J, Lee HK, Ko Y, Kim H, Fang S. ID1-Mediated BMP Signaling Pathway Potentiates Glucagon-Like Peptide-1 Secretion in Response to Nutrient Replenishment. Int J Mol Sci 2020; 21:ijms21113824. [PMID: 32481541 PMCID: PMC7311998 DOI: 10.3390/ijms21113824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 12/02/2022] Open
Abstract
Glucagon-like peptide-1 (GLP-1) is a well-known incretin hormone secreted from enteroendocrinal L cells in response to nutrients, such as glucose and dietary fat, and controls glycemic homeostasis. However, the detailed intracellular mechanisms of how L cells control GLP-1 secretion in response to nutrients still remain unclear. Here, we report that bone morphogenetic protein (BMP) signaling pathway plays a pivotal role to control GLP-1 secretion in response to nutrient replenishment in well-established mouse enteroendocrinal L cells (GLUTag cells). Nutrient starvation dramatically reduced cellular respiration and GLP-1 secretion in GLUTag cells. Transcriptome analysis revealed that nutrient starvation remarkably reduced gene expressions involved in BMP signaling pathway, whereas nutrient replenishment rescued BMP signaling to potentiate GLP-1 secretion. Transient knockdown of inhibitor of DNA binding (ID)1, a well-known target gene of BMP signaling, remarkably reduced GLP-1 secretion. Consistently, LDN193189, an inhibitor of BMP signaling, markedly reduced GLP-1 secretion in L cells. In contrast, BMP4 treatment activated BMP signaling pathway and potentiated GLP-1 secretion in response to nutrient replenishment. Altogether, we demonstrated that BMP signaling pathway is a novel molecular mechanism to control GLP-1 secretion in response to cellular nutrient status. Selective activation of BMP signaling would be a potent therapeutic strategy to stimulate GLP-1 secretion in order to restore glycemic homeostasis.
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Affiliation(s)
- Jae Woong Jeong
- Department of Medicine, Yonsei University College of Medicine, Seoul 03722, Korea;
| | - Minki Kim
- Department of Medical Science, BK21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea;
| | - Jiwoo Lee
- Severance Biomedical Science Institute, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Korea; (J.L.); (H.-K.L.)
| | - Hae-Kyung Lee
- Severance Biomedical Science Institute, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Korea; (J.L.); (H.-K.L.)
| | - Younhee Ko
- Division of Biomedical Engineering, Hankuk University of Foreign Studies, Yongin 17035, Korea;
| | - Hyunkyung Kim
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 02841, Korea
- Correspondence: (H.K.); (S.F.)
| | - Sungsoon Fang
- Department of Medical Science, BK21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea;
- Severance Biomedical Science Institute, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Korea; (J.L.); (H.-K.L.)
- Correspondence: (H.K.); (S.F.)
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Metabolomics Analysis of Nutrient Metabolism in β-Cells. J Mol Biol 2020; 432:1429-1445. [DOI: 10.1016/j.jmb.2019.07.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/03/2019] [Accepted: 07/11/2019] [Indexed: 01/05/2023]
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14
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Wang J, Zhou J, Bai S. Combination of Glutamine and Ulinastatin Treatments Greatly Improves Sepsis Outcomes. J Inflamm Res 2020; 13:109-115. [PMID: 32110086 PMCID: PMC7037133 DOI: 10.2147/jir.s234122] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/10/2019] [Indexed: 12/28/2022] Open
Abstract
Background Sepsis is one of the most dangerous syndromes, has extremely high mortality, and is caused by the body’s extreme responses to an infection. The pathogenesis of sepsis is very complex and remains largely unknown and thus the treatments for sepsis are limited. Here, we evaluated the treatment results of two potential drugs, glutamine and ulinastatin, on sepsis. Methods CLP rat model was used to study sepsis. Gastrostomy was performed to deliver the drugs. Flow cytometry was employed to measure CD4 and CD8 levels. May–Grünwald–Giemsa staining was used to count the numbers of monocytes and neutrophils in the blood. ELISA assay was performed to assess the levels of PCT, IL-6, TNFα, and IL-1β. Results Sepsis was successfully induced with the standard CLP rat model. Both glutamine and ulinastatin treatments greatly improved the outcomes of sepsis, but the combination of both treatments had the maximum therapeutic effect. Mechanistically, PCT, IL-6, TNFα, and IL-1β levels were significantly diminished following glutamine and ulinastatin treatments, suggesting an inhibition of inflammatory responses. Further, CD4 and CD4/CD8 ratio, and the numbers of monocytes and neutrophils were greatly up-regulated by glutamine and ulinastatin, indicating an enhanced immunity. Conclusion Glutamine and ulinastatin treatments largely mitigate sepsis shock by suppressing the inflammatory responses of the body and strengthening the immune system. Combination of these two drugs could serve as a potential treatment for sepsis.
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Affiliation(s)
- Junyan Wang
- Department of Critical Care Medicine, Baotou Central Hospital, Baotou, Inner Mongolia, People's Republic of China
| | - Jiahui Zhou
- Department of Anesthesiology, Baotou Central Hospital, Baotou, Inner Mongolia, People's Republic of China
| | - Shuancheng Bai
- Department of Anesthesiology, Baotou Central Hospital, Baotou, Inner Mongolia, People's Republic of China
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15
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Tang C, Ksiazek I, Siccardi N, Gapp B, Weber D, Wirsching J, Beck V, Reist M, Gaudet L, Stuber N, Surber SS, Mao X, Nicholson TB, Carbone W, Beibel M, Roma G, Gubser Keller C, Bassilana F. UTS2B Defines a Novel Enteroendocrine Cell Population and Regulates GLP-1 Secretion Through SSTR5 in Male Mice. Endocrinology 2019; 160:2849-2860. [PMID: 31556942 DOI: 10.1210/en.2019-00549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 09/20/2019] [Indexed: 12/25/2022]
Abstract
The gut-pancreas axis plays a key role in the regulation of glucose homeostasis and may be therapeutically exploited to treat not only type 2 diabetes but also hypoglycemia and hyperinsulinemia. We identify a novel enteroendocrine cell type expressing the peptide hormone urotensin 2B (UTS2B). UTS2B inhibits glucagon-like peptide-1 (GLP-1) secretion in mouse intestinal crypts and organoids, not by signaling through its cognate receptor UTS2R but through the activation of the somatostatin receptor (SSTR) 5. Circulating UTS2B concentrations in mice are physiologically regulated during starvation, further linking this peptide hormone to metabolism. Furthermore, administration of UTS2B to starved mice demonstrates that it is capable of regulating blood glucose and plasma concentrations of GLP-1 and insulin in vivo. Altogether, our results identify a novel cellular source of UTS2B in the gut, which acts in a paracrine manner to regulate GLP-1 secretion through SSTR5. These findings uncover a fine-tuning mechanism mediated by a ligand-receptor pair in the regulation of gut hormone secretion, which can potentially be exploited to correct metabolic unbalance caused by overactivation of the gut-pancreas axis.
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Affiliation(s)
- Cong Tang
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Iwona Ksiazek
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Noemie Siccardi
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Berangere Gapp
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Delphine Weber
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | - Valerie Beck
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Matthias Reist
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Laurent Gaudet
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Nathalie Stuber
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | - Xiaohong Mao
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts
| | | | - Walter Carbone
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Martin Beibel
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Guglielmo Roma
- Novartis Institutes for BioMedical Research, Basel, Switzerland
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Ding M, Fang QH, Cui YT, Shen QL, Liu Q, Wang PH, Yu DM, Li CJ. Liraglutide prevents β-cell apoptosis via inactivation of NOX2 and its related signaling pathway. J Diabetes Complications 2019; 33:267-277. [PMID: 30772113 DOI: 10.1016/j.jdiacomp.2018.12.013] [Citation(s) in RCA: 15] [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: 10/30/2018] [Revised: 11/20/2018] [Accepted: 12/26/2018] [Indexed: 01/01/2023]
Abstract
AIMS High glucose (HG)-induced pancreatic β-cell apoptosis may be a major contributor to the progression of diabetes mellitus (DM). NADPH oxidase (NOX2) has been considered a crucial regulator in β-cell apoptosis. This study was designed to evaluate the impact of GLP-1 receptor agonist (GLP-1Ra) liraglutide on pancreatic β-cell apoptosis in diabetes and the underlying mechanisms involved. METHODS The diabetic rat models induced by streptozotocin (STZ) and a high fat diet (HFD) received 12 weeks of liraglutide treatment. Hyperglycemic clamp test was carried out to evaluate β-cell function in vivo. Flow cytometry analysis was used to measure apoptosis rates in vitro. DCFH-DA method was used to detected ROS level in vivo and in vitro. RESULTS Liraglutide significantly improved islet function and morphology in diabetic rats and decreased cell apoptosis rates. Thr183/Thr185 p-JNK1/2 and NOX2 levels reduced in diabetic rats and HG-induced INS-1 cell following liraglutide treatment. In addition, liraglutide upregulated the phosphorylation of AMPKα (p-AMPKα), which prevented NOX2 activation and alleviated HG-induced β-cell apoptosis. CONCLUSION The p-AMPKα/NOX2/JNK1/2 pathway is essential for liraglutide to attenuate HG-induced β-cell apoptosis, which further proves that GLP-1Ras may become promising therapeutics for diabetes mellitus.
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Affiliation(s)
- Min Ding
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Qian-Hua Fang
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Yuan-Tao Cui
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Qi-Ling Shen
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Qian Liu
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - Peng-Hua Wang
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China
| | - De-Min Yu
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China.
| | - Chun-Jun Li
- NHC Key Laboratory of Hormones and Development (Tianjin Medical University), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Medical University Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin 300070, PR China.
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17
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Darmaun D, Torres-Santiago L, Mauras N. Glutamine and type 1 diabetes mellitus: is there a role in glycemic control? Curr Opin Clin Nutr Metab Care 2019; 22:91-95. [PMID: 30461450 DOI: 10.1097/mco.0000000000000530] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW Recent literature suggests dietary glutamine supplementation may lower blood glucose in patients with type 1 diabetes (T1D), who have no residual insulin secretion. The mechanisms and potential relevance to the care of T1D remain unclear. RECENT FINDINGS Glutamine is involved in multiple pathways including gluconeogenesis, lipolysis, antioxidant defense, the production of nitric oxide, the secretion of peptides (e.g., glucagon-like peptide 1, GLP-1), or neuromediators (e.g., [Latin Small Letter Gamma]-aminobutyric acid), all processes that may impact insulin sensitivity and/or glucose homeostasis. The article reviews potential mechanisms and literature evidence suggesting a role in improving glucose tolerance in patients with illness associated with insulin resistance, as well as the preliminary evidence for the increased incidence of postexercise hypoglycemia in T1D after oral glutamine. SUMMARY Further studies are warranted to determine whether the lowering effect of glutamine on blood glucose is sustained over time. If so, long-term randomized trials would be warranted to determine whether there is a role for glutamine as an adjunct dietary supplement to improve glucose control in patients with T1D.
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Affiliation(s)
- Dominique Darmaun
- Department of Pediatric Endocrinology and Metabolism, Nemours Children's Health System, Jacksonville, Florida, USA
- INRA and University of Nantes, IMAD, CRNH-Ouest, Nantes, France
| | - Lournaris Torres-Santiago
- Department of Pediatric Endocrinology and Metabolism, Nemours Children's Health System, Jacksonville, Florida, USA
| | - Nelly Mauras
- Department of Pediatric Endocrinology and Metabolism, Nemours Children's Health System, Jacksonville, Florida, USA
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Mathioudakis L, Bourbouli M, Daklada E, Kargatzi S, Michaelidou K, Zaganas I. Localization of Human Glutamate Dehydrogenases Provides Insights into Their Metabolic Role and Their Involvement in Disease Processes. Neurochem Res 2018; 44:170-187. [PMID: 29943084 DOI: 10.1007/s11064-018-2575-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/11/2018] [Accepted: 06/13/2018] [Indexed: 12/21/2022]
Abstract
Glutamate dehydrogenase (GDH) catalyzes the reversible deamination of L-glutamate to α-ketoglutarate and ammonia. In mammals, GDH contributes to important processes such as amino acid and carbohydrate metabolism, energy production, ammonia management, neurotransmitter recycling and insulin secretion. In humans, two isoforms of GDH are found, namely hGDH1 and hGDH2, with the former being ubiquitously expressed and the latter found mainly in brain, testis and kidney. These two iso-enzymes display highly divergent allosteric properties, especially concerning their basal activity, ADP activation and GTP inhibition. On the other hand, both enzymes are thought to predominantly localize in the mitochondrial matrix, even though alternative localizations have been proposed. To further study the subcellular localization of the two human iso-enzymes, we created HEK293 cell lines stably over-expressing hGDH1 and hGDH2. In these cell lines, immunofluorescence and enzymatic analyses verified the overexpression of both hGDH1 and hGDH2 iso-enzymes, whereas subcellular fractionation followed by immunoblotting showed their predominantly mitochondrial localization. Given that previous studies have only indirectly compared the subcellular localization of the two iso-enzymes, we co-expressed them tagged with different fluorescent dyes (green and red fluorescent protein for hGDH1 and hGDH2, respectively) and found them to co-localize. Despite the wealth of information related to the functional properties of hGDH1 and hGDH2 and the availability of the hGDH1 structure, there is still an ongoing debate concerning their metabolic role and their involvement in disease processes. Data on the localization of hGDHs, as the ones presented here, could contribute to better understanding of the function of these important human enzymes.
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Affiliation(s)
- Lambros Mathioudakis
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Mara Bourbouli
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Elisavet Daklada
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Sofia Kargatzi
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Kleita Michaelidou
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Ioannis Zaganas
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece. .,Department of Neurology, University Hospital of Heraklion, Heraklion, Crete, Greece.
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