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Tran M, Gilling S, Wu J, Wang L, Shin DJ. miR-141/200c contributes to ethanol-mediated hepatic glycogen metabolism. Mol Metab 2024; 84:101942. [PMID: 38642890 PMCID: PMC11060962 DOI: 10.1016/j.molmet.2024.101942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 04/15/2024] [Indexed: 04/22/2024] Open
Abstract
OBJECTIVE Hepatic glucose metabolism is profoundly perturbed by excessive alcohol intake. miR-141/200c expression is significantly induced by chronic ethanol feeding. This study aimed at identifying the role of miR-141/200c in glucose homeostasis during chronic ethanol exposure. METHODS WT and miR-141/200c KO mice were fed a control or an ethanol diet for 30 days, followed by a single binge of maltose dextrin or ethanol, respectively. Untargeted metabolomics analysis of hepatic primary metabolites was performed along with analyses for liver histology, gene expression, intracellular signaling pathways, and physiological relevance. Primary hepatocytes were used for mechanistic studies. RESULTS miR-141/200c deficiency rewires hepatic glucose metabolism during chronic ethanol feeding, increasing the abundance of glucose intermediates including G6P, an allosteric activator for GS. miR-141/200c deficiency replenished glycogen depletion during chronic ethanol feeding accompanied by reduced GS phosphorylation in parallel with increased expression of PP1 glycogen targeting subunits. Moreover, miR-141/200c deficiency prevented ethanol-mediated increases in AMPK and CaMKK2 activity. Ethanol treatment reduced glycogen content in WT-hepatocytes, which was reversed by dorsomorphin, a selective AMPK inhibitor, while KO-hepatocytes displayed higher glycogen content than WT-hepatocytes in response to ethanol treatment. Furthermore, treatment of hepatocytes with A23187, a calcium ionophore activating CaMKK2, lowered glycogen content in WT-hepatocytes. Notably, the suppressive effect of A23187 on glycogen deposition was reversed by dorsomorphin, demonstrating that the glycogen depletion by A23187 is mediated by AMPK. KO-hepatocytes exhibited higher glycogen content than WT-hepatocytes in response to A23187. Finally, miR-141/200c deficiency led to improved glucose tolerance and insulin sensitivity during chronic ethanol feeding. CONCLUSIONS miR-141/200c deficiency replenishes ethanol-mediated hepatic glycogen depletion through the regulation of GS activity and calcium signaling coupled with the AMPK pathway, improving glucose homeostasis and insulin sensitivity. These results underscore miR-141/200c as a potential therapeutic target for the management of alcohol intoxication.
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Affiliation(s)
- Melanie Tran
- Department of Physiology and Neurobiology, University of Connecticut, 75 N. Eagleville Rd, Storrs, CT 06269, USA
| | - Shaynian Gilling
- Department of Physiology and Neurobiology, University of Connecticut, 75 N. Eagleville Rd, Storrs, CT 06269, USA
| | - Jianguo Wu
- Department of Physiology and Neurobiology, University of Connecticut, 75 N. Eagleville Rd, Storrs, CT 06269, USA
| | - Li Wang
- Department of Internal Medicine, Section of Digestive Diseases, Yale University, 333 Cedar St, New Haven, CT 06510, USA
| | - Dong-Ju Shin
- Department of Physiology and Neurobiology, University of Connecticut, 75 N. Eagleville Rd, Storrs, CT 06269, USA.
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Active Glycogen Synthase in the Liver Prevents High-Fat Diet-Induced Glucose Intolerance, Decreases Food Intake, and Lowers Body Weight. Int J Mol Sci 2023; 24:ijms24032574. [PMID: 36768897 PMCID: PMC9917303 DOI: 10.3390/ijms24032574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/31/2023] Open
Abstract
Many lines of evidence demonstrate a correlation between liver glycogen content and food intake. We previously demonstrated that mice overexpressing protein targeting to glycogen (PTG) specifically in the liver-which have increased glycogen content in this organ-are protected from high-fat diet (HFD)-induced obesity by reduced food intake. However, the use of PTG to increase liver glycogen implies certain limitations. PTG stimulates glycogen synthesis but also inhibits the enzyme responsible for glycogen degradation. Furthermore, as PTG is a regulatory subunit of protein phosphatase 1 (PP1), which regulates many cellular functions, its overexpression could have side effects beyond the regulation of glycogen metabolism. Therefore, it is necessary to determine whether the direct activation of glycogen synthesis, without affecting its degradation or other cellular functions, has the same effects. To this end, we generated mice overexpressing a non-inactivatable form of glycogen synthase (GS) specifically in the liver (9A-MGSAlb mice). Control and 9a-MGSAlb mice were fed a standard diet (SD) or HFD for 16 weeks. Glucose tolerance and feeding behavior were analyzed. 9A-MGSAlb mice showed an increase in hepatic glycogen in fed and fasting conditions. When fed an HFD, these animals preserved their hepatic energy state, had a reduced food intake, and presented a lower body weight and fat mass than control animals, without changes in energy expenditure. Furthermore, 9A-MGSAlb animals showed improved glucose tolerance when fed an SD or HFD. Moreover, liver triacylglycerol levels that were increased after HFD feeding were lower in these mice. These results confirm that increased liver glycogen stores contribute to decreased appetite and improve glucose tolerance in mice fed an HFD. On the basis of our findings, strategies to preserve hepatic glycogen stores emerge as potential treatments for obesity and hyperglycemia.
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Dong L, Qin C, Li Y, Wu Z, Liu L. Oat phenolic compounds regulate metabolic syndrome in high fat diet-fed mice via gut microbiota. FOOD BIOSCI 2022. [DOI: 10.1016/j.fbio.2022.101946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Ramadan NM, Elmasry K, Elsayed HRH, El-Mesery A, Eraky SM. The hepatoprotective effects of n3-polyunsaturated fatty acids against non-alcoholic fatty liver disease in diabetic rats through the FOXO1/PPARα/GABARAPL1 signalling pathway. Life Sci 2022; 311:121145. [DOI: 10.1016/j.lfs.2022.121145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 10/26/2022] [Accepted: 10/29/2022] [Indexed: 11/06/2022]
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Aktaş İ, Mehmet Gür F. Hepato-protective effects of thymoquinone and beta-aminoisobutyric acid in streptozocin induced diabetic rats. Biotech Histochem 2021; 97:67-76. [PMID: 34281431 DOI: 10.1080/10520295.2021.1949041] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
We investigated the hepato-protective effects of thymoquinone (TQ) and beta-aminoisobutyric acid (BAIBA). We used five groups of 8-week-old male rats: untreated control group, streptozotocin (STZ) diabetic group, STZ + TQ group, STZ + BAIBA group, and STZ + TQ + BAIBA group. After experimental diabetes mellitus (DM) was established using STZ, TQ was given to the STZ + TQ group, BAIBA to the STZ + BAIBA group, and TQ and BAIBA to the STZ + TQ + BAIBA group. In the STZ group, body weight, relative liver weight, and glutathione, blood albumin and insulin levels were decreased compared to the control. Also, water and food consumption, tumor necrosis factor-α expression, malondialdehyde, blood glucose, alanine aminotransferase, aspartate aminotransferase and gamma glutamyl transferase levels were increased the STZ group compared to the control group. In the STZ group, sinusoid congestion and dilation, monocyte and lymphocyte infiltration and microvesicular steatosis were observed in the liver tissue. Pathological changes caused by DM were reduced significantly in the STZ + TQ, STZ + BAIBA and STZ + TQ + BAIBA groups. The protective effect of BAIBA was greater than for TQ; the greatest protective effect was observed following combined use of TQ + BAIBA. We suggest that our findings for the STZ + TQ, STZ + BAIBA and STZ + TQ + BAIBA groups were due to the antioxidant effects of TQ and BAIBA. TQ and BAIBA appear to be potential therapeutic agents for ameliorating hepatic damage due to DM.
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Affiliation(s)
- İbrahim Aktaş
- Department of Pharmacology, Vocational School of Health Services, Adiyaman University, Adiyaman, Turkey
| | - Fatih Mehmet Gür
- Department of Histology and Embryology, Faculty of Medicine, Niğde Ömer Halisdemir University, Niğde, Turkey
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6
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López-Soldado I, Guinovart JJ, Duran J. Increasing hepatic glycogen moderates the diabetic phenotype in insulin-deficient Akita mice. J Biol Chem 2021; 296:100498. [PMID: 33667544 PMCID: PMC8027280 DOI: 10.1016/j.jbc.2021.100498] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/23/2021] [Accepted: 03/01/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatic glycogen metabolism is impaired in diabetes. We previously demonstrated that strategies to increase liver glycogen content in a high-fat-diet mouse model of obesity and insulin resistance led to a reduction in food intake and ameliorated obesity and glucose tolerance. These effects were accompanied by a decrease in insulin levels, but whether this decrease contributed to the phenotype observed in this animal was unclear. Here we sought to evaluate this aspect directly, by examining the long-term effects of increasing liver glycogen in an animal model of insulin-deficient and monogenic diabetes, namely the Akita mouse, which is characterized by reduced insulin production. We crossed Akita mice with animals overexpressing protein targeting to glycogen (PTG) in the liver to generate Akita mice with increased liver glycogen content (Akita-PTGOE). Akita-PTGOE animals showed lower glycemia, lower food intake, and decreased water consumption and urine output compared with Akita mice. Furthermore, Akita-PTGOE mice showed a restoration of the hepatic energy state and a normalization of gluconeogenesis and glycolysis back to nondiabetic levels. Moreover, hepatic lipogenesis, which is reduced in Akita mice, was reverted in Akita-PTGOE animals. These results demonstrate that strategies to increase liver glycogen content lead to the long-term reduction of the diabetic phenotype, independently of circulating insulin.
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Affiliation(s)
- Iliana López-Soldado
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.
| | - Joan J Guinovart
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain; Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Barcelona, Spain
| | - Jordi Duran
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
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Shill MC, Bepari AK, Khan M, Tasneem Z, Ahmed T, Hasan MA, Alam MJ, Hossain M, Rahman MA, Sharker SM, Shahriar M, Rahman GMS, Reza HM. Therapeutic Potentials of Colocasia affinis Leaf Extract for the Alleviation of Streptozotocin-Induced Diabetes and Diabetic Complications: In vivo and in silico-Based Studies. J Inflamm Res 2021; 14:443-459. [PMID: 33642871 PMCID: PMC7903966 DOI: 10.2147/jir.s297348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 01/27/2021] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION Hypoglycemia in diabetes mellitus (DM) correlates with hepatic impairment, nephropathy, lipid abnormalities, and oxidative stress and subsequently complicates the disease pathogenesis. Medicinal plants have been used for the management of diabetes since ancient times. In this study, we explored the potentials of Colocasia affinis (CA), a plant known to possess anti-allergic and anti-inflammatory activities, as a remedy for diabetes and related complications. METHODS We induced diabetes in rats using a single intraperitoneal dose (65 mg/kg) of streptozotocin (STZ). We next treated the rats with an ethanolic extract of leaves of CA to reveal its antidiabetic and organ-protective potentials. Biomarkers of diabetes, inflammation, and oxidative stress were measured using biochemical and histopathological analysis. We also performed molecular docking for three major phytochemicals (kaempferol, myricetin, and rosmarinic acid) of CA. RESULTS Oral administration of the CA leaves extract at 250 mg/kg and 500 mg/kg doses decreased blood glucose level significantly (p<0.05) in STZ-induced diabetic rats. The extract also considerably attenuated plasma HbA1c levels and normalized blood lipids, glycogen, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Additionally, treatment with the extract improved kidney complications by decreasing serum creatinine and blood urea nitrogen (BUN) levels. Furthermore, CA leaves extract normalized nitric oxide (NO) and advance oxidative protein products (AOPP) in diabetic rats. The extract also showed significant improvement of the antioxidant enzymes glutathione dismutase (GSH) and superoxide dismutase (SOD) at a dose of 500 mg/kg. Besides, histological investigation demonstrated attenuation of inflammation of the vital organs, including the liver and the kidney. In silico studies revealed that three major phytochemicals (kaempferol, myricetin, and rosmarinic acid) of the ethanolic extract of leaves of CA can inhibit several molecular targets of diabetes and inflammation. CONCLUSION Collectively, our results demonstrated the therapeutic potentials of CA for the mitigation of diabetes and diabetic complications.
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Affiliation(s)
- Manik Chandra Shill
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Asim Kumar Bepari
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Mahi Khan
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Zarin Tasneem
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Tania Ahmed
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Md Asif Hasan
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Md Jahir Alam
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Murad Hossain
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Md Ashrafur Rahman
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Shazid Md Sharker
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
| | - Masum Shahriar
- Department of Pharmacy, Jahangirnagar University, Savar, Bangladesh
| | | | - Hasan Mahmud Reza
- Department of Pharmaceutical Sciences, North South University, Bashundhara, Dhaka, 1229, Bangladesh
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López-Soldado I, Bertini A, Adrover A, Duran J, Guinovart JJ. Maintenance of liver glycogen during long-term fasting preserves energy state in mice. FEBS Lett 2020; 594:1698-1710. [PMID: 32159852 DOI: 10.1002/1873-3468.13770] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/20/2020] [Accepted: 03/04/2020] [Indexed: 12/17/2022]
Abstract
Glycogen shortage during fasting coincides with dramatic changes in hepatic adenine nucleotide levels. The aim of this work was to study the relevance of liver glycogen in the regulation of the hepatic energy state during food deprivation. To this end, we examined the response of mice with sustained increased liver glycogen content to prolonged fasting. In order to increase hepatic glycogen content, we generated mice that overexpress protein targeting to glycogen (PTG) in the liver (PTGOE mice). Control and PTGOE mice were fed ad libitum or fasted for 36 h. Upon fasting, PTGOE mice retained significant hepatic glycogen stores and maintained hepatic energy status. Furthermore, we show that liver glycogen controls insulin sensitivity, gluconeogenesis, lipid metabolism, and ketogenesis upon nutrient deprivation.
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Affiliation(s)
- Iliana López-Soldado
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Angelo Bertini
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain
| | - Anna Adrover
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Jordi Duran
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Joan J Guinovart
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.,Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Spain
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Hu TG, Wen P, Liu J, Long XS, Liao ST, Wu H, Zou YX. Combination of mulberry leaf and oat bran possessed greater hypoglycemic effect on diabetic mice than mulberry leaf or oat bran alone. J Funct Foods 2019. [DOI: 10.1016/j.jff.2019.103503] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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10
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Hu TG, Wen P, Shen WZ, Liu F, Li Q, Li EN, Liao ST, Wu H, Zou YX. Effect of 1-Deoxynojirimycin Isolated from Mulberry Leaves on Glucose Metabolism and Gut Microbiota in a Streptozotocin-Induced Diabetic Mouse Model. JOURNAL OF NATURAL PRODUCTS 2019; 82:2189-2200. [PMID: 31393724 DOI: 10.1021/acs.jnatprod.9b00205] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
1-Deoxynojirimycin (DNJ) exerts hypoglycemic effects. However, the traditional method for DNJ extraction is inefficient, and the hypoglycemic mechanism of DNJ remains unclear. In this study, the mixed fermentation by Lactobacillus fermentum and Saccharomyces cerevisiae was used to enhance DNJ extraction efficiency. It was found that this strategy was more efficient than the traditional method as the yield improved from the original 3.24 mg/g to 5.97 mg/g. The purified DNJ significantly decreased serum glucose (P < 0.01) and insulin levels (P < 0.05), improved serum lipid levels (P < 0.05), and reversed insulin resistance (P < 0.05) in diabetic mice. These changes were caused by up-regulating the protein expression of insulin receptor and glycolysis enzymes (GK, PK, and PFK) (P < 0.05) and down-regulating the protein expression of insulin receptor substrate-1 and gluconeogenesis enzymes (PCB, PEPCK, FBPase, and G-6-Pase) (P < 0.05), thus alleviating glucose tolerance. Additionally, DNJ treatment relieved gut dysbiosis in diabetic mice by promoting the growth of Lactobacillus, Lachnospiraceae NK4A136 group, Oscillibacter, norank Lachnospiraceae, Alistipes, and Bifidobacterium (P < 0.05) and suppressing the growth of Ruminococcaceae UCG-014, Weissella, Ruminococcus, Prevotellaceae Ga6A1 group, Anaerostipes, Klebsiella, Prevotellaceae UCG-001, and Bacteroidales S24-7 group (P < 0.05).
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Affiliation(s)
- Teng-Gen Hu
- School of Food Science and Engineering , South China University of Technology/Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety , Guangzhou 510640 , China
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
| | - Peng Wen
- School of Food Science and Engineering , South China University of Technology/Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety , Guangzhou 510640 , China
| | - Wei-Zhi Shen
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
| | - Fan Liu
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
| | - Qian Li
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
| | - Er-Na Li
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
| | - Sen-Tai Liao
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
| | - Hong Wu
- School of Food Science and Engineering , South China University of Technology/Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety , Guangzhou 510640 , China
| | - Yu-Xiao Zou
- Sericultural and Agri-Food Research Institute , Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing , Guangzhou 510610 , China
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Zhang Y, Shu G, Bai Y, Chao J, Chen X, Yao H. Effect of methamphetamine on the fasting blood glucose in methamphetamine abusers. Metab Brain Dis 2018; 33:1585-1597. [PMID: 29946958 DOI: 10.1007/s11011-018-0265-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/04/2018] [Indexed: 11/30/2022]
Abstract
Methamphetamine is a popular psychostimulant worldwide which causes neurotoxicity and neuroinflammation. Although previous studies have characterized potential associations between addictive drugs and fasting blood glucose, the influence of methamphetamine on the blood glucose is still largely unknown. The present study was designed to investigate the change of fasting blood glucose of methamphetamine abusers and to confirm the impairment of liver and kidney. Fasting blood glucose was significantly decreased in methamphetamine abusers and in a high-fat diet mouse model with methamphetamine treatment discontinuation. Serum level of ALT, creatine kinase and creatinine were increased in methamphetamine abusers. Serum level of ALT and AST were increased in a high-fat diet mouse model after methamphetamine injection, but there was no significant difference in the anatomy of the liver and kidney in high-fat diet treated mice with or without methamphetamine. The levels of ALT and creatinine were also increased in the methamphetamine abusers. This study demonstrated that the level of glucose was decreased in methamphetamine abusers and in high-fat diet-fed mice after methamphetamine treatment discontinuation. The effect of methamphetamine on the levels of blood glucose may provide the evidence that methamphetamine abusers should be keep energy balance due to the low blood glucose.
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Affiliation(s)
- Yanhong Zhang
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China
| | - Guofang Shu
- Department of Clinical Laboratory, Zhongda Hospital, Southeast University School of Medicine, Nanjing, 210009, Jiangsu, China
| | - Ying Bai
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China
| | - Jie Chao
- Department of Physiology, Medical School of Southeast University, Nanjing, China
| | - Xufeng Chen
- Department of Emergency, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
| | - Honghong Yao
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China.
- Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, Jiangsu, China.
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12
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Abdelazim A, Khater S, Ali H, Shalaby S, Afifi M, Saddick S, Alkaladi A, Almaghrabi OA. Panax ginseng improves glucose metabolism in streptozotocin-induced diabetic rats through 5' adenosine monophosphate kinase up-regulation. Saudi J Biol Sci 2018; 26:1436-1441. [PMID: 31762606 PMCID: PMC6864146 DOI: 10.1016/j.sjbs.2018.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/09/2018] [Accepted: 06/04/2018] [Indexed: 12/12/2022] Open
Abstract
5′ AMP-activated protein kinase (AMPK), insulin receptors and transporters are distorted in diabetes mellitus. In this study, the effect of Panax ginseng was assessed on glucose manipulating enzymes activities and gene expression of AMPK, IRA and GLUT2 in streptozotocin-induced diabetic male rats. Forty male albino rats were randomly divided to four groups 10 rats of each, group I, normal control group (received saline orally); group II, normal rats received 200 mg/kg of Panax ginseng orally; group III, Streptozotocin (STZ) –induced diabetic rats and group IV, STZ-induced diabetic rats received 200 mg/kg of Panax ginseng orally. The duration of experiment was 30 days. Results showed the ability of Panax ginseng to induce a significant decrease in the blood glucose and increase in the serum insulin levels, hepatic glucokinase (GK), and glycogen synthase (GS) activities with a modulation of lipid profile besides high expression levels of AMPK, insulin receptor A (IRA), glucose transporting protein-2 (GLUT-2) in liver of diabetic rats. In conclusion, the obtained results point to the ability of Panax ginseng to improve the glucose metabolism in diabetic models.
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Affiliation(s)
- Aaser Abdelazim
- Department of Biochemistry, Faculty of Vet. Medicine, Zagazig University, Zagazig, Egypt.,Department of Basic Medical Sciences, College of Applied Medical Sciences, University of Bisha, Bisha, Saudi Arabia
| | - Safaa Khater
- Department of Biochemistry, Faculty of Vet. Medicine, Zagazig University, Zagazig, Egypt
| | - Haytham Ali
- Department of Biochemistry, Faculty of Vet. Medicine, Zagazig University, Zagazig, Egypt.,Department of Biological Sciences, Faculty of Science, University of Jeddah, Saudi Arabia
| | - Shimaa Shalaby
- Department of Physiology, Faculty of Vet. Medicine, Zagazig University, Zagazig, Egypt
| | - Mohamed Afifi
- Department of Biochemistry, Faculty of Vet. Medicine, Zagazig University, Zagazig, Egypt.,Department of Biological Sciences, Faculty of Science, University of Jeddah, Saudi Arabia.,University of Jeddah Center for Scientific and Medical Research, University of Jeddah, Saudi Arabia
| | - Salina Saddick
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
| | - Ali Alkaladi
- Department of Biological Sciences, Faculty of Science, University of Jeddah, Saudi Arabia
| | - Omar A Almaghrabi
- Department of Biological Sciences, Faculty of Science, University of Jeddah, Saudi Arabia
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13
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Li T, Ni L, Zhao Z, Liu X, Lai Z, Di X, Xie Z, Song X, Wang X, Zhang R, Liu C. Melatonin attenuates smoking-induced hyperglycemia via preserving insulin secretion and hepatic glycogen synthesis in rats. J Pineal Res 2018; 64:e12475. [PMID: 29437243 PMCID: PMC5947659 DOI: 10.1111/jpi.12475] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 02/02/2018] [Indexed: 12/11/2022]
Abstract
Epidemiology survey indicated that cigarette smoking is a risk factor of diabetes. However, the precise mechanisms remain to be clarified. In this study, we found that smoking caused metabolic malfunctions on pancreas and liver in experimental animal model. These were indicated by hyperglycemia, increased serum hemoglobin A1c level and decreased insulin secretion, inhibition of liver glycogen synthase (LGS), and hepatic glycogen synthesis. Mechanistic studies revealed that all these alterations were caused by the inflammatory reaction and reactive oxygen species (ROS) induced by the smoking. Melatonin treatment significantly preserved the functions of both pancreas and liver by reducing β cell apoptosis, CD68-cell infiltration, ROS production, and caspase-3 expression. The siRNA-knockdown model identified that the protective effects of melatonin were mediated by melatonin receptor-2 (MT2). This study uncovered potentially underlying mechanisms related to the association between smoking and diabetes. In addition, it is, for first time, to report that melatonin effectively protects against smoking-induced glucose metabolic alterations and the signal transduction pathway of melatonin is mainly mediated by its MT2 receptor. These observations provide solid evidence for the clinically use of melatonin to reduce smoking-related diabetes, and the therapeutic regimens are absent currently.
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Affiliation(s)
- Tianjia Li
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Leng Ni
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Zhewei Zhao
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Xinnong Liu
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Zhichao Lai
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Xiao Di
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Zhibo Xie
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Xitao Song
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Xuebin Wang
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Rui Zhang
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Changwei Liu
- Department of Vascular SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
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Ahmed MA, Mohamed MA, Rashed LA, Abd Elbast SA, Ahmed EA. Rice Bran Oil Improves Insulin Resistance by Affecting the Expression of Antioxidants and Lipid-Regulatory Genes. Lipids 2018; 53:505-515. [DOI: 10.1002/lipd.12045] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Affiliation(s)
- Mervat A. Ahmed
- Zoology Department; Al-Azhar University, Yossuf Abbas St., PO Box 11754; Cairo Egypt
| | - Mona A. Mohamed
- Biochemistry Division, Chemistry Department, Faculty of Science; Al-Azhar University, Yossuf Abbas St., PO Box 11754; Cairo Egypt
| | - Laila A. Rashed
- Biochemistry Department; Cairo University; El-Kasr El-Aeni St., PO Box 12613, Cairo Egypt
| | - Sohaier A. Abd Elbast
- Zoology Department; Al-Azhar University, Yossuf Abbas St., PO Box 11754; Cairo Egypt
| | - Elham A. Ahmed
- Zoology Department; Al-Azhar University, Yossuf Abbas St., PO Box 11754; Cairo Egypt
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15
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Hypoglycemic effect and mechanism of a pectic polysaccharide with hexenuronic acid from the fruits of Ficus pumila L. in C57BL/KsJ db/db mice. Carbohydr Polym 2017; 178:209-220. [DOI: 10.1016/j.carbpol.2017.09.050] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 09/06/2017] [Accepted: 09/13/2017] [Indexed: 12/20/2022]
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16
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López-Soldado I, Fuentes-Romero R, Duran J, Guinovart JJ. Effects of hepatic glycogen on food intake and glucose homeostasis are mediated by the vagus nerve in mice. Diabetologia 2017; 60:1076-1083. [PMID: 28299379 DOI: 10.1007/s00125-017-4240-4] [Citation(s) in RCA: 21] [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: 12/12/2016] [Accepted: 02/14/2017] [Indexed: 10/20/2022]
Abstract
AIMS/HYPOTHESIS Liver glycogen plays a key role in regulating food intake and blood glucose. Mice that accumulate large amounts of this polysaccharide in the liver are protected from high-fat diet (HFD)-induced obesity by reduced food intake. Furthermore, these animals show reversal of the glucose intolerance and hyperinsulinaemia caused by the HFD. The aim of this study was to examine the involvement of the hepatic branch of the vagus nerve in regulating food intake and glucose homeostasis in this model. METHODS We performed hepatic branch vagotomy (HBV) or a sham operation on mice overexpressing protein targeting to glycogen (Ptg OE). Starting 1 week after surgery, mice were fed an HFD for 10 weeks. RESULTS HBV did not alter liver glycogen or ATP levels, thereby indicating that this procedure does not interfere with hepatic energy balance. However, HBV reversed the effect of glycogen accumulation on food intake. In wild-type mice, HBV led to a significant reduction in body weight without a change in food intake. Consistent with their body weight reduction, these animals had decreased fat deposition, adipocyte size, and insulin and leptin levels, together with increased energy expenditure. Ptg OE mice showed an increase in energy expenditure and glucose oxidation, and these differences were abolished by HBV. Moreover, Ptg OE mice showed an improvement in HFD-induced glucose intolerance, which was suppressed by HBV. CONCLUSIONS/INTERPRETATION Our results demonstrate that the regulation of food intake and glucose homeostasis by liver glycogen is dependent on the hepatic branch of the vagus nerve.
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Affiliation(s)
- Iliana López-Soldado
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10, 08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Rebeca Fuentes-Romero
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10, 08028, Barcelona, Spain
| | - Jordi Duran
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10, 08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Joan J Guinovart
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10, 08028, Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.
- Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Barcelona, Spain.
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Irimia JM, Meyer CM, Segvich DM, Surendran S, DePaoli-Roach AA, Morral N, Roach PJ. Lack of liver glycogen causes hepatic insulin resistance and steatosis in mice. J Biol Chem 2017; 292:10455-10464. [PMID: 28483921 DOI: 10.1074/jbc.m117.786525] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 05/06/2017] [Indexed: 01/16/2023] Open
Abstract
Disruption of the Gys2 gene encoding the liver isoform of glycogen synthase generates a mouse strain (LGSKO) that almost completely lacks hepatic glycogen, has impaired glucose disposal, and is pre-disposed to entering the fasted state. This study investigated how the lack of liver glycogen increases fat accumulation and the development of liver insulin resistance. Insulin signaling in LGSKO mice was reduced in liver, but not muscle, suggesting an organ-specific defect. Phosphorylation of components of the hepatic insulin-signaling pathway, namely IRS1, Akt, and GSK3, was decreased in LGSKO mice. Moreover, insulin stimulation of their phosphorylation was significantly suppressed, both temporally and in an insulin dose response. Phosphorylation of the insulin-regulated transcription factor FoxO1 was somewhat reduced and insulin treatment did not elicit normal translocation of FoxO1 out of the nucleus. Fat overaccumulated in LGSKO livers, showing an aberrant distribution in the acinus, an increase not explained by a reduction in hepatic triglyceride export. Rather, when administered orally to fasted mice, glucose was directed toward hepatic lipogenesis as judged by the activity, protein levels, and expression of several fatty acid synthesis genes, namely, acetyl-CoA carboxylase, fatty acid synthase, SREBP1c, chREBP, glucokinase, and pyruvate kinase. Furthermore, using cultured primary hepatocytes, we found that lipogenesis was increased by 40% in LGSKO cells compared with controls. Of note, the hepatic insulin resistance was not associated with increased levels of pro-inflammatory markers. Our results suggest that loss of liver glycogen synthesis diverts glucose toward fat synthesis, correlating with impaired hepatic insulin signaling and glucose disposal.
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Affiliation(s)
- Jose M Irimia
- From the Departments of Biochemistry and Molecular Biology and
| | | | - Dyann M Segvich
- From the Departments of Biochemistry and Molecular Biology and
| | - Sneha Surendran
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | | | - Nuria Morral
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Peter J Roach
- From the Departments of Biochemistry and Molecular Biology and
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A novel formula Sang-Tong-Jian improves glycometabolism and ameliorates insulin resistance by activating PI3K/AKT pathway in type 2 diabetic KKAy mice. Biomed Pharmacother 2016; 84:1585-1594. [DOI: 10.1016/j.biopha.2016.10.101] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/17/2016] [Accepted: 10/17/2016] [Indexed: 12/29/2022] Open
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Hepatic Overexpression of CD36 Improves Glycogen Homeostasis and Attenuates High-Fat Diet-Induced Hepatic Steatosis and Insulin Resistance. Mol Cell Biol 2016; 36:2715-2727. [PMID: 27528620 DOI: 10.1128/mcb.00138-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 08/10/2016] [Indexed: 11/20/2022] Open
Abstract
The common complications in obesity and type 2 diabetes include hepatic steatosis and disruption of glucose-glycogen homeostasis, leading to hyperglycemia. Fatty acid translocase (FAT/CD36), whose expression is inducible in obesity, is known for its function in fatty acid uptake. Previous work by us and others suggested that CD36 plays an important role in hepatic lipid homeostasis, but the results have been conflicting and the mechanisms were not well understood. In this study, by using CD36-overexpressing transgenic (CD36Tg) mice, we uncovered a surprising function of CD36 in regulating glycogen homeostasis. Overexpression of CD36 promoted glycogen synthesis, and as a result, CD36Tg mice were protected from fasting hypoglycemia. When challenged with a high-fat diet (HFD), CD36Tg mice showed unexpected attenuation of hepatic steatosis, increased very low-density lipoprotein (VLDL) secretion, and improved glucose tolerance and insulin sensitivity. The HFD-fed CD36Tg mice also showed decreased levels of proinflammatory hepatic prostaglandins and 20-hydroxyeicosatetraenoic acid (20-HETE), a potent vasoconstrictive and proinflammatory arachidonic acid metabolite. We propose that CD36 functions as a protective metabolic sensor in the liver under lipid overload and metabolic stress. CD36 may be explored as a valuable therapeutic target for the management of metabolic syndrome.
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20
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Liu Q, Li X, Li C, Zheng Y, Wang F, Li H, Peng G. 1-Deoxynojirimycin Alleviates Liver Injury and Improves Hepatic Glucose Metabolism in db/db Mice. Molecules 2016; 21:279. [PMID: 26927057 PMCID: PMC6274115 DOI: 10.3390/molecules21030279] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 02/21/2016] [Accepted: 02/23/2016] [Indexed: 12/30/2022] Open
Abstract
The present study investigated the effect of 1-Deoxynojirimycin (DNJ) on liver injury and hepatic glucose metabolism in db/db mice. Mice were divided into five groups: normal control, db/db control, DNJ-20 (DNJ 20 mg·kg−1·day−1), DNJ-40 (DNJ 40 mg·kg−1·day−1) and DNJ-80 (DNJ 80 mg·kg−1·day−1). All doses were treated intravenously by tail vein for four weeks. DNJ was observed to significantly reduce the levels of serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and liver TG, as well as activities of serum alanine aminotransferase (ALT), and aspartate transaminase (AST); DNJ also alleviated macrovesicular steatosis and decreased tumor necrosis factor α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6) levels in liver tissue. Furthermore, DNJ treatment significantly increased hepatic glycogen content, the activities of hexokinase (HK), pyruvate kinase (PK) in liver tissue, and decreased the activities of glucose-6-phosphatase (G6Pase), glycogen phosphorylase (GP), and phosphoenolpyruvate carboxykinase (PEPCK). Moreover, DNJ increased the phosphorylation of phosphatidylinositol 3 kinase (PI3K) on p85, protein kinase B (PKB) on Ser473, glycogen synthase kinase 3β (GSK-3β) on Ser9, and inhibited phosphorylation of glycogen synthase (GS) on Ser645 in liver tissue of db/db mice. These results demonstrate that DNJ can increase hepatic insulin sensitivity via strengthening of the insulin-stimulated PKB/GSK-3β signal pathway and by modulating glucose metabolic enzymes in db/db mice. Moreover, DNJ also can improve lipid homeostasis and attenuate hepatic steatosis in db/db mice.
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Affiliation(s)
- Qingpu Liu
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Xuan Li
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Cunyu Li
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China.
| | - Yunfeng Zheng
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China.
| | - Fang Wang
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Hongyang Li
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Guoping Peng
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China.
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Lozano I, Van der Werf R, Bietiger W, Seyfritz E, Peronet C, Pinget M, Jeandidier N, Maillard E, Marchioni E, Sigrist S, Dal S. High-fructose and high-fat diet-induced disorders in rats: impact on diabetes risk, hepatic and vascular complications. Nutr Metab (Lond) 2016; 13:15. [PMID: 26918024 PMCID: PMC4766713 DOI: 10.1186/s12986-016-0074-1] [Citation(s) in RCA: 191] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 02/11/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND As a result of the increased consumption of sugar-rich and fatty-products, and the increase in preference for such products, metabolic disorders are becoming more common at a younger age. Fructose is particularly used in prepared foods and carbonated beverages. We investigated the impact of regular consumption of fructose, in combination or not with fatty food, on the onset of metabolic syndrome and type 2 diabetes (T2D). We evaluated the metabolic, oxidative, and functional effects on the liver and blood vessels, both related to diabetes complications. METHODS High-fat diet (HFD), high-fructose beverages (HF) or both (HFHF) were compared to rats fed with normal diet (ND) for 8 months to induce T2D and its metabolic, oxidative, and functional complications. Metabolic control was determined by measuring body weight, fasting blood glucose, C-peptide, HOMA2-IR, leptin, and cholesterol; oxidative parameters were studied by lipid peroxidation and total antioxidant capacity in plasma and the use of ROS labelling on tissue. Histological analysis was performed on the liver and endothelial function was performed in main mesenteric artery using organ-baths. RESULTS After 2 months, HFHF and HFD increased body weight, leptin, HOMA2-IR associated to steatosis, oxidative stress in plasma and tissues, whereas HF had only a transient increase of leptin and c-peptide. Only HFHF induced fasting hyperglycaemia after 6 months and persistent hyperinsulinaemia and fasting hyperglycaemia with complicated steatosis (inflammation and fibrosis) after 8 months. HFHF and HFD induced endothelial dysfunction at 8 months of diet. CONCLUSIONS Six months, high fat and high carbohydrate induced T2D with widespread tissues effects. We demonstrated the role of oxidative stress in pathogenesis as well as in complications (hepatic and vascular), reinforcing interest in the use of antioxidants in the prevention and treatment of metabolic diseases, including T2D.
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Affiliation(s)
- Iona Lozano
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
| | - Remmelt Van der Werf
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France ; Equipe de Chimie Analytique des Molécules BioActives, IPHC-LC4, UMR 7178, Faculté de Pharmacie, Ilkirch, France
| | - William Bietiger
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
| | - Elodie Seyfritz
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
| | - Claude Peronet
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
| | - Michel Pinget
- Structure d'Endocrinologie, Diabète, Nutrition et Addictologie, Pôle NUDE, Hôpitaux Universitaires de Strasbourg, (HUS), 67000 Strasbourg, France
| | - Nathalie Jeandidier
- Structure d'Endocrinologie, Diabète, Nutrition et Addictologie, Pôle NUDE, Hôpitaux Universitaires de Strasbourg, (HUS), 67000 Strasbourg, France
| | - Elisa Maillard
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
| | - Eric Marchioni
- Equipe de Chimie Analytique des Molécules BioActives, IPHC-LC4, UMR 7178, Faculté de Pharmacie, Ilkirch, France
| | - Séverine Sigrist
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
| | - Stéphanie Dal
- UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France
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Anti-diabetes effect of chronic intermittent hypobaric hypoxia through improving liver insulin resistance in diabetic rats. Life Sci 2016; 150:1-7. [PMID: 26883978 DOI: 10.1016/j.lfs.2016.02.053] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 01/06/2016] [Accepted: 02/12/2016] [Indexed: 12/16/2022]
Abstract
AIM Cumulating evidence demonstrated that chronic intermittent hypobaric hypoxia (CIHH) had beneficial effects on the body. The present study was to investigate the anti-diabetes effect of CIHH in type-2 diabetic rats for the first time. MAIN METHODS Sprague-Dawley rats were randomly divided into 4 groups: control group (CON), diabetes mellitus group (DM, induced by high-fat diet combined with low-dose streptozotocin), CIHH treatment group (CIHH, simulated 5000-m altitude, 6h per day for 28 days), and diabetes mellitus plus CIHH treatment group (DM+CIHH). Histopathology of liver, systolic arterial blood pressure (SAP), blood biochemicals, glucose and insulin tolerance were determined. The expression of proteins associated with insulin signaling pathway as well as hypoxia induced factors were assayed. KEY FINDINGS Diabetic rats showed impaired glucose tolerance, dyslipidemia, hepatic steatosis and hepatic insulin resistance in addition to increased SAP. However, SAP, serum triglyceride and cholesterol were decreased, and hepatic steatosis and insulin resistance were improved in DM+CIHH rats. Furthermore, the protein expression of glucokinase (GCK), insulin receptor substrates (IRS-1 and IRS-2), and HIF1α were increased, while the expression of phosphoenolpyruvate carboxykinase (PEPCK), was markedly reduced in DM+CIHH rats. SIGNIFICANCE We conclude that CIHH treatment has anti-diabetes effects through ameliorating insulin resistance via hepatic HIF-insulin signaling pathway in type-2 diabetic rats.
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López-Soldado I, Zafra D, Duran J, Adrover A, Calbó J, Guinovart JJ. Liver glycogen reduces food intake and attenuates obesity in a high-fat diet-fed mouse model. Diabetes 2015; 64:796-807. [PMID: 25277398 DOI: 10.2337/db14-0728] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We generated mice that overexpress protein targeting to glycogen (PTG) in the liver (PTG(OE)), which results in an increase in liver glycogen. When fed a high-fat diet (HFD), these animals reduced their food intake. The resulting effect was a lower body weight, decreased fat mass, and reduced leptin levels. Furthermore, PTG overexpression reversed the glucose intolerance and hyperinsulinemia caused by the HFD and protected against HFD-induced hepatic steatosis. Of note, when fed an HFD, PTG(OE) mice did not show the decrease in hepatic ATP content observed in control animals and had lower expression of neuropeptide Y and higher expression of proopiomelanocortin in the hypothalamus. Additionally, after an overnight fast, PTG(OE) animals presented high liver glycogen content, lower liver triacylglycerol content, and lower serum concentrations of fatty acids and β-hydroxybutyrate than control mice, regardless of whether they were fed an HFD or a standard diet. In conclusion, liver glycogen accumulation caused a reduced food intake, protected against the deleterious effects of an HFD, and diminished the metabolic impact of fasting. Therefore, we propose that hepatic glycogen content be considered a potential target for the pharmacological manipulation of diabetes and obesity.
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Affiliation(s)
- Iliana López-Soldado
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain CIBERDEM, Madrid, Spain
| | - Delia Zafra
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain CIBERDEM, Madrid, Spain
| | - Jordi Duran
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain CIBERDEM, Madrid, Spain
| | - Anna Adrover
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
| | - Joaquim Calbó
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain CIBERDEM, Madrid, Spain
| | - Joan J Guinovart
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain CIBERDEM, Madrid, Spain Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
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Otero YF, Stafford JM, McGuinness OP. Pathway-selective insulin resistance and metabolic disease: the importance of nutrient flux. J Biol Chem 2015; 289:20462-9. [PMID: 24907277 DOI: 10.1074/jbc.r114.576355] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hepatic glucose and lipid metabolism are altered in metabolic disease (e.g. obesity, metabolic syndrome, and Type 2 diabetes). Insulin-dependent regulation of glucose metabolism is impaired. In contrast, lipogenesis, hypertriglyceridemia, and hepatic steatosis are increased. Because insulin promotes lipogenesis and liver fat accumulation, to explain the elevation in plasma and tissue lipids, investigators have suggested the presence of pathway-selective insulin resistance. In this model, insulin signaling to glucose metabolism is impaired, but insulin signaling to lipid metabolism is intact. We discuss the evidence for the differential regulation of hepatic lipid and glucose metabolism. We suggest that the primary phenotypic driver is altered substrate delivery to the liver, as well as the repartitioning of hepatic nutrient handling. Specific alterations in insulin signaling serve to amplify the alterations in hepatic substrate metabolism. Thus, hyperinsulinemia and its resultant increased signaling may facilitate lipogenesis, but are not the major drivers of the phenotype of pathway-selective insulin resistance.
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25
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Over-expression of muscle glycogen synthase in human diabetic nephropathy. Histochem Cell Biol 2014; 143:313-24. [PMID: 25371328 DOI: 10.1007/s00418-014-1290-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2014] [Indexed: 01/15/2023]
Abstract
Diabetic nephropathy (DN) is a major complication of diabetic patients and the leading cause of end-stage renal disease. Glomerular dysfunction plays a critical role in DN, but deterioration of renal function also correlates with tubular alterations. Human DN is characterized by glycogen accumulation in tubules. Although this pathological feature has long been recognized, little information exists about the triggering mechanism. In this study, we detected over-expression of muscle glycogen synthase (MGS) in diabetic human kidney. This enhanced expression suggests the participation of MGS in renal metabolic changes associated with diabetes. HK2 human renal cell line exhibited an intrinsic ability to synthesize glycogen, which was enhanced after over-expression of protein targeting to glycogen. A correlation between increased glycogen amount and cell death was observed. Based on a previous transcriptome study on human diabetic kidney disease, significant differences in the expression of genes involved in glycogen metabolism were analyzed. We propose that glucose, but not insulin, is the main modulator of MGS activity in HK2 cells, suggesting that blood glucose control is the best approach to modulate renal glycogen-induced damage during long-term diabetes.
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Zhang L, Xu J, Song H, Yao Z, Ji G. Extracts from Salvia-Nelumbinis naturalis alleviate hepatosteatosis via improving hepatic insulin sensitivity. J Transl Med 2014; 12:236. [PMID: 25160038 PMCID: PMC4244055 DOI: 10.1186/s12967-014-0236-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 08/20/2014] [Indexed: 12/13/2022] Open
Abstract
Background Salvia-Nelumbinis naturalis (SNN), initially called Jiangzhi Granula as a formulae of Chinese medicinal decoction, has been used clinically to treat non-alcoholic fatty liver disease (NAFLD) and related syndromes. The mechanism of SNN action is unknown. Methods HepG2 cells were cultured in lipid-rich media supplemented with chemical components of SNN. Male Wistar rats (6 weeks of age) were fed a high calorie diet (15% fat, 15% sucrose, and 2% cholesterol) for eight weeks, and then treated with SNN for four weeks. Body and liver weight, lipids profiles, insulin and glucose levels, glucose and insulin tolerance were evaluated, the mRNA and protein expression of insulin receptor (InsR), insulin receptor substrate (IRS) 1/2, protein kinase B (PKB/Akt), protein expression of suppressor of cytokine signaling 3 (SOCS3), protein kinase C epsilon (PKC ε) in liver tissue were analysed. Results Treatment with SNN components in lipid-laden HepG2 cells decreased lipid accumulation. Rats fed with a HC diet developed hepatosteatosis and accompanied hyperglycemia, hyperinsulinemia, hyperleptinemia, and diabetic dyslipidemia. Prolonged HC diet feeding resulted in parabolic response in plasma triglyceride (TG) concentrations, indicative of compromised hepatic production of TG-rich lipoproteins. HC diet feeding also resulted in impaired insulin sensitivity and hepatic insulin signalling. Administration of SNN extracts alleviated hepatosteatosis and conferred to a normolipoproteinemia profile in the HC diet-fed rats. The efficacy of SNN extract in improving liver function and insulin sensitivity was comparable to that of simvastatin or pioglitazone. The improved insulin signaling by SNN treatment was associated with increased IRS and Akt phosphorylation and decreased SOCS3 expression. However, SNN failed to inhibit the PKC ε expression in the liver. Conclusions SNN is effective in reducing lipid accumulation in HepG2 cells and attenuating hepatosteatosis in HC diet-fed rats. Reduced hepatic lipid content in the rat liver was associated with improved insulin signalling.
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Affiliation(s)
| | | | | | | | - Guang Ji
- Institute of Digestive Disease, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
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Stapleton DI, Lau X, Flores M, Trieu J, Gehrig SM, Chee A, Naim T, Lynch GS, Koopman R. Dysfunctional muscle and liver glycogen metabolism in mdx dystrophic mice. PLoS One 2014; 9:e91514. [PMID: 24626262 PMCID: PMC3953428 DOI: 10.1371/journal.pone.0091514] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 02/11/2014] [Indexed: 12/25/2022] Open
Abstract
Background Duchenne muscular dystrophy (DMD) is a severe, genetic muscle wasting disorder characterised by progressive muscle weakness. DMD is caused by mutations in the dystrophin (dmd) gene resulting in very low levels or a complete absence of the dystrophin protein, a key structural element of muscle fibres which is responsible for the proper transmission of force. In the absence of dystrophin, muscle fibres become damaged easily during contraction resulting in their degeneration. DMD patients and mdx mice (an animal model of DMD) exhibit altered metabolic disturbances that cannot be attributed to the loss of dystrophin directly. We tested the hypothesis that glycogen metabolism is defective in mdx dystrophic mice. Results Dystrophic mdx mice had increased skeletal muscle glycogen (79%, (P<0.01)). Skeletal muscle glycogen synthesis is initiated by glycogenin, the expression of which was increased by 50% in mdx mice (P<0.0001). Glycogen synthase activity was 12% higher (P<0.05) but glycogen branching enzyme activity was 70% lower (P<0.01) in mdx compared with wild-type mice. The rate-limiting enzyme for glycogen breakdown, glycogen phosphorylase, had 62% lower activity (P<0.01) in mdx mice resulting from a 24% reduction in PKA activity (P<0.01). In mdx mice glycogen debranching enzyme expression was 50% higher (P<0.001) together with starch-binding domain protein 1 (219% higher; P<0.01). In addition, mdx mice were glucose intolerant (P<0.01) and had 30% less liver glycogen (P<0.05) compared with control mice. Subsequent analysis of the enzymes dysregulated in skeletal muscle glycogen metabolism in mdx mice identified reduced glycogenin protein expression (46% less; P<0.05) as a possible cause of this phenotype. Conclusion We identified that mdx mice were glucose intolerant, and had increased skeletal muscle glycogen but reduced amounts of liver glycogen.
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Affiliation(s)
- David I Stapleton
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Xianzhong Lau
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Marcelo Flores
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jennifer Trieu
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Stefan M Gehrig
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Annabel Chee
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Timur Naim
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Gordon S Lynch
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - René Koopman
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
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Chen LN, Lyu J, Yang XF, Ji WJ, Yuan BX, Chen MX, Ma X, Wang B. Liraglutide ameliorates glycometabolism and insulin resistance through the upregulation of GLUT4 in diabetic KKAy mice. Int J Mol Med 2013; 32:892-900. [PMID: 23877319 DOI: 10.3892/ijmm.2013.1453] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 07/12/2013] [Indexed: 11/06/2022] Open
Abstract
Liraglutide, a long-lasting glucagon‑like peptide‑1 analogue, has been used for the treatment of patients with type 2 diabetes mellitus since 2009. In this study, we investigated the anti-diabetic effects and mechanisms of action of liraglutide in a spontaneous diabetic animal model, using KK/Upj-Ay/J (KKAy) mice. The KKAy mice were divided into 2 groups, the liraglutide group (mice were treated with 250 µg/kg/day liraglutide) and the model group (treated with an equivalent amount of normal saline). C57BL/6J mice were used as the controls (treated with an equivalent amount of normal saline). The treatment period lasted 6 weeks. During this treatment period, fasting blood glucose (FBG) levels and the body weight of the mice were measured on a weekly basis. Our results revealed that liraglutide significantly decreased FBG levels, the area under the curve following a oral glucose tolerance test and insulin tolerance test, increased serum insulin levels, reduced homeostasis model assessment of insulin resistance and increased the insulin sensitivity index. Furthermore, liraglutide ameliorated glycometabolism dysfunction by increasing glycolysis via hexokinase and glycogenesis via pyruvate kinase activation. An ultrastructural examination of the pancreas revealed that liraglutide improved the damaged state of islet β cells and increased the number of insulin secretory granules. The real-time PCR results revealed that the gene expression of glucose transporter 4 (GLUT4) increased following treatment with liraglutide. Liraglutide also upregulated the protein expression of GLUT4 in liver tissue and skeletal muscle. Our results suggest that liraglutide ameliorates glycometabolism and insulin resistance in diabetic KKAy mice by stimulating insulin secretion, increasing glycogenesis and glycolysis and upregulating the expression of GLUT4.
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Affiliation(s)
- Li-Na Chen
- Department of Pharmacology, College of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, PR China
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Zafra D, Nocito L, Domínguez J, Guinovart JJ. Sodium tungstate activates glycogen synthesis through a non-canonical mechanism involving G-proteins. FEBS Lett 2012; 587:291-6. [PMID: 23260418 DOI: 10.1016/j.febslet.2012.11.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 11/28/2012] [Accepted: 11/30/2012] [Indexed: 12/28/2022]
Abstract
Tungstate treatment ameliorates experimental diabetes by increasing liver glycogen deposition through an as yet unidentified mechanism. The signalling mechanism of tungstate was studied in CHOIR cells and primary cultured hepatocytes. This compound exerted its pro-glycogenic effects through a new G-protein-dependent and Tyr-Kinase Receptor-independent mechanism. Chemical or genetic disruption of G-protein signalling prevented the activation of the Ras/ERK cascade and the downstream induction of glycogen synthesis caused by tungstate. Thus, these findings unveil a novel non-canonical signalling pathway that leads to the activation of glycogen synthesis and that could be exploited as an approach to treat diabetes.
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Affiliation(s)
- Delia Zafra
- Institute for Research in Biomedicine (IRB Barcelona) and Department of Biochemistry and Molecular Biology, University of Barcelona, and CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM), Baldiri Reixac 10-12, E-08028 Barcelona, Spain
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Soares AF, Carvalho RA, Veiga FJ, Alves MG, Martins FO, Viegas I, González JD, Metón I, Baanante IV, Jones JG. Restoration of direct pathway glycogen synthesis flux in the STZ-diabetes rat model by insulin administration. Am J Physiol Endocrinol Metab 2012; 303:E875-85. [PMID: 22850684 DOI: 10.1152/ajpendo.00161.2012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Type 1 diabetes subjects are characterized by impaired direct pathway synthesis of hepatic glycogen that is unresponsive to insulin therapy. Since it is not known whether this is an irreversible defect of insulin-dependent diabetes, direct and indirect pathway glycogen fluxes were quantified in streptozotocin (STZ)-induced diabetic rats and compared with STZ rats that received subcutaneous or intraperitoneal insulin (I-SC or I-IP). Three groups of STZ rats were studied at 18 days post-STZ treatment. One group was administered I-SC and another I-IP as two daily injections of short-acting insulin at the start of each light and dark period for days 9-18. A third group did not receive any insulin, and a fourth group of nondiabetic rats was used as control. Glycogen synthesis via direct and indirect pathways, de novo lipogenesis, and gluconeogenesis were determined over the nocturnal feeding period using deuterated water. Direct pathway was residual in STZ rats, and glucokinase activity was also reduced significantly from control levels. Insulin administration restored both net glycogen synthesis via the direct pathway and glucokinase activity to nondiabetic control levels and improved the lipogenic pathway despite an inefficient normalization of the gluconeogenic pathway. We conclude that the reduced direct pathway flux is not an irreversible defect of insulin-dependent diabetes.
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Affiliation(s)
- Ana F Soares
- Center for Neuroscience and Cell Biology, Dept. of Life Sciences, Univ. of Coimbra, Largo Marquês de Pombal, 3004 - 517, Coimbra, Portugal
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