Crucial roles of neuronatin in insulin secretion and high glucose-induced apoptosis in pancreatic β-cells

2008 ◽  
Vol 20 (5) ◽  
pp. 907-915 ◽  
Author(s):  
Myung Kuk Joe ◽  
Hyo Jung Lee ◽  
Young Ho Suh ◽  
Kyu Lee Han ◽  
Joo Hyun Lim ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
High Glucose ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Induced Apoptosis

Delphinidin-induced autophagy protects pancreatic β cells against apoptosis resulting from high-glucose stress via AMPK signaling pathway

2019 ◽  
Vol 51 (12) ◽  
pp. 1242-1249 ◽  
Author(s):  
Dengni Lai ◽  
Mingyong Huang ◽  
Lingyan Zhao ◽  
Yan Tian ◽  
Yong Li ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
High Glucose ◽  
Cell Mass ◽  
Protective Role ◽  
Common Disease ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Ampk Signaling ◽  
Compound C ◽  
Induced Apoptosis

Abstract Hyperglycemia, a diagnostic characteristic of diabetes mellitus, is detrimental to pancreatic β cells. Delphinidin, a member of the anthocyanin family, inhibits glucose absorption, increases glucagon-like peptide-1 (GLP-1) secretion, and improves insulin secretion in diabetes. However, whether delphinidin plays a protective role in pancreatic β-cell mass and function is not clear. In this study, delphinidin was found to decrease the high-glucose-induced apoptosis of RIN-m5F pancreatic β cells. In addition, delphinidin induced autophagy in RIN-m5F cells under the normal and high-glucose conditions, while 3-methyladenine (3-MA) inhibition of autophagy significantly diminished the protective role of delphinidin against high-glucose-induced apoptosis of pancreatic β cells. Delphinidin also decreased the level of cleaved caspase 3 and increased the phosphorylation level of AMP-activated protein kinase α (AMPKα) Thr172. Compound C, an AMPK inhibitor, was found to decrease the ratio of LC3-II/LC3-I, and the apoptotic rate of high-glucose-injured cells was increased after treatment with delphinidin, indicating that delphinidin attenuated the negative effects of high-glucose stress to cells. In conclusion, our data demonstrate that delphinidin protects pancreatic β cells against high-glucose-induced injury by autophagy regulation via the AMPK signaling pathway. These findings might shed light on the underlying mechanisms of diabetes and help improve the prevention and therapy of this common disease.

scholarly journals Protective Effect of Siegesbeckia orientalis on Pancreatic β-Cells under High Glucose-Induced Glucotoxicity

2021 ◽  
Vol 11 (22) ◽  
pp. 10963
Author(s):  
Chi-Chang Chang ◽  
Jer-Yiing Houng ◽  
Shih-Wei Wang ◽  
Chin-Feng Hsuan ◽  
Yung-Chuan Lu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Insulin Secretion ◽  
Protective Effect ◽  
Normal Level ◽  
High Glucose ◽  
Glucose Concentration ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Siegesbeckia Orientalis

The glucotoxicity caused by long-term exposure of β-cells to high glucose (HG) conditions may lead to the generation of more reactive oxygen species (ROS), reduce the activity of antioxidant enzymes, cause cell damage and apoptosis, and induce insulin secretion dysfunction. Siegesbeckia orientalis linne is a traditional folk herbal medicine used to treat snake bites, rheumatoid arthritis, allergies, and immune deficiencies. In this study, we evaluated the protective effect of S. orientalis ethanol extract (SOE) on cell death and oxidative stress in RIN-m5f pancreatic β-cells stimulated by two HG concentrations (50–100 mM). In the cell viability assay, SOE could significantly increase the survival rate of pancreatic β-cells under HG-induced conditions. For the oxidative stress induced by HG condition, the treatment of SOE effectively reduced the ROS formation, increased the content of intracellular glutathione, and up-regulated the expression of antioxidant enzymes, catalase, superoxide dismutase, and glutathione peroxidase. As a result, the SOE treatment could decrease the glucotoxicity-mediated oxidative damage on RIN-m5F β-cells. Moreover, SOE had the function of regulating insulin secretion in pancreatic β-cells under different HG-mediated conditions. It could decrease the increasing intracellular insulin secretion under the low glucose concentration to normal level; while increase the decreasing intracellular insulin secretion under the relatively high glucose concentration to normal level. Taken together, this study suggests that SOE has a protective effect on pancreatic β-cells under the HG-stimulated glucotoxic environment.

Cyanidin-3-rutinoside protects INS-1 pancreatic β cells against high glucose-induced glucotoxicity by apoptosis

2018 ◽  
Vol 73 (7-8) ◽  
pp. 281-289 ◽  
Author(s):  
Kung-Ha Choi ◽  
Mi Hwa Park ◽  
Hyun Ah Lee ◽  
Ji-Sook Han
Keyword(s):  
Cell Death ◽  
High Glucose ◽  
Cell Damage ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Pancreatic Β Cell ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
Induced Apoptosis

Abstract Exposure to high levels of glucose may cause glucotoxicity, leading to pancreatic β cell dysfunction, including cell apoptosis and impaired glucose-stimulated insulin secretion. The aim of this study was to explore the effect of cyanidin-3-rutinoside (C3R), a derivative of anthocyanin, on glucotoxicity-induced apoptosis in INS-1 pancreatic β cells. Glucose (30 mM) treatment induced INS-1 pancreatic β cell death, but glucotoxicity and apoptosis significantly decreased in cells treated with 50 μM C3R compared to that observed in 30 mM glucose-treated cells. Furthermore, hyperglycemia increased intracellular reactive oxygen species (ROS), lipid peroxidation, and nitric oxide (NO) levels, while C3R treatment reduced these in a dose-dependent manner. C3R also increased the activity of antioxidant enzymes, markedly reduced the expression of pro-apoptotic proteins (such as Bax, cytochrome c, caspase 9 and caspase 3), and increased the expression of the anti-apoptotic protein, Bcl-2, in hyperglycemia-exposed cells. Finally, cell death was examined using annexin V/propidium iodide staining, which revealed that C3R significantly reduced high glucose-induced apoptosis. In conclusion, C3R may have therapeutic effects against hyperglycemia-induced β cell damage in diabetes.

scholarly journals PRMT4 is involved in insulin secretion via the methylation of histone H3 in pancreatic β cells

2015 ◽  
Vol 54 (3) ◽  
pp. 315-324 ◽  
Author(s):  
Joong Kwan Kim ◽  
Yongchul Lim ◽  
Jung Ok Lee ◽  
Young-Sun Lee ◽  
Nam Hee Won ◽  
...  
Keyword(s):  
Gene Expression ◽  
Insulin Secretion ◽  
High Glucose ◽  
Histone H3 ◽  
Insulin Gene ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Protein Arginine Methyltransferases ◽  
Insulin Synthesis ◽  
Insulin Gene Expression

The relationship between protein arginine methyltransferases (PRMTs) and insulin synthesis in β cells is not yet well understood. In the present study, we showed that PRMT4 expression was increased in INS-1 and HIT-T15 pancreatic β cells under high-glucose conditions. In addition, asymmetric dimethylation of Arg17 in histone H3 was significantly increased in both cell lines in the presence of glucose. The inhibition or knockdown of PRMT4 suppressed glucose-induced insulin gene expression in INS-1 cells by 81.6 and 79% respectively. Additionally, the overexpression of mutant PRMT4 also significantly repressed insulin gene expression. Consistently, insulin secretion induced in response to high levels of glucose was decreased by both PRMT4 inhibition and knockdown. Moreover, the inhibition of PRMT4 blocked high-glucose-induced insulin gene expression and insulin secretion in primary pancreatic islets. These results indicate that PRMT4 might be a key regulator of high-glucose-induced insulin secretion from pancreatic β cells via H3R17 methylation.

scholarly journals Glucose-Dependent Changes in SNARE Protein Levels in Pancreatic β-Cells

Endocrinology ◽  
2011 ◽  
Vol 152 (4) ◽  
pp. 1290-1299 ◽  
Author(s):  
Benjamín Torrejón-Escribano ◽  
Jessica Escoriza ◽  
Eduard Montanya ◽  
Juan Blasi
Keyword(s):  
Insulin Secretion ◽  
Protein Expression ◽  
High Glucose ◽  
Glucose Concentration ◽  
Snare Proteins ◽  
High Glucose Concentration ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
In Vivo Models ◽  
Insulin Granule

Abstract Prolonged exposure to high glucose concentration alters the expression of a set of proteins in pancreatic β-cells and impairs their capacity to secrete insulin. The cellular and molecular mechanisms that lie behind this effect are poorly understood. In this study, three either in vitro or in vivo models (cultured rat pancreatic islets incubated in high glucose media, partially pancreatectomized rats, and islets transplanted to streptozotozin-induced diabetic mice) were used to evaluate the dependence of the biological model and the treatment, together with the cell location (insulin granule or plasma membrane) of the affected proteins and the possible effect of sustained insulin secretion, on the glucose-induced changes in protein expression. In all three models, islets exposed to high glucose concentrations showed a reduced expression of secretory granule-associated vesicle-soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins synaptobrevin/vesicle-associated membrane protein 2 and cellubrevin but minor or no significant changes in the expression of the membrane-associated target-SNARE proteins syntaxin1 and synaptosomal-associated protein-25 and a marked increase in the expression of synaptosomal-associated protein-23 protein. The inhibition of insulin secretion by the L-type voltage-dependent calcium channel nifedipine or the potassium channel activator diazoxide prevented the glucose-induced reduction in islet insulin content but not in vesicle-SNARE proteins, indicating that the granule depletion due to sustained exocytosis was not involved in the changes of protein expression induced by high glucose concentration. Altogether, the results suggest that high glucose has a direct toxic effect on the secretory pathway by decreasing the expression of insulin granule SNARE-associated proteins.

Sign in / Sign up

Export Citation Format

Share Document