scholarly journals Chebulic Acid Prevents Methylglyoxal-Induced Mitochondrial Dysfunction in INS-1 Pancreatic β-Cells

Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 771
Author(s):  
Hyun-jung Yoo ◽  
Chung-Oui Hong ◽  
Sang Keun Ha ◽  
Kwang-Won Lee
Keyword(s):  
Enzyme Activity ◽  
Protein Expression ◽  
Western Blot ◽  
Mitochondrial Dysfunction ◽  
Atp Synthesis ◽  
Ros Production ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Chebulic Acid ◽  
Cyt C

To investigate the anti-diabetic properties of chebulic acid (CA) associated with the prevention of methyl glyoxal (MG)-induced mitochondrial dysfunction in INS-1 pancreatic β-cells, INS-1 cells were pre-treated with CA (0.5, 1.0, and 2.0 μM) for 48 h and then treated with 2 mM MG for 8 h. The effects of CA and MG on INS-1 cells were evaluated using the following: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; glyoxalase 1 (Glo-1) expression via Western blot and enzyme activity assays; Nrf-2, nuclear factor erythroid 2-related factor 2 protein expression via Western blot assay; reactive oxygen species (ROS) production assay; mRNA expression of mitochondrial dysfunction related components (UCP2, uncoupling protein 2; VDAC1, voltage-dependent anion-selective channel-1; cyt c, cytochrome c via quantitative reverse transcriptase-PCR; mitochondrial membrane potential (MMP); adenosine triphosphate (ATP) synthesis; glucose-stimulated insulin secretion (GSIS) assay. The viability of INS-1 cells was maintained upon pre-treating with CA before exposure to MG. CA upregulated Glo-1 protein expression and enzyme activity in INS-1 cells and prevented MG-induced ROS production. Mitochondrial dysfunction was alleviated by CA pretreatment; this occurred via the downregulation of UCP2, VDAC1, and cyt c mRNA expression and the increase of MMP and ATP synthesis. Further, CA pre-treatment promoted the recovery from MG-induced decrease in GSIS. These results indicated that CA could be employed as a therapeutic agent in diabetes due to its ability to prevent MG-induced development of insulin sensitivity and oxidative stress-induced dysfunction of β-cells.

Glucolipotoxicity-induced oxidative stress is related to mitochondrial dysfunction and apoptosis of pancreatic β-cell

2020 ◽  
Vol 16 ◽  
Author(s):  
Jorge E. Vela-Guajardo ◽  
Salvador Garza-González ◽  
Noemí García
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Insulin Secretion ◽  
Mitochondrial Dysfunction ◽  
Mitochondrial Dynamics ◽  
Atp Synthesis ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
Diabetes Development

: Glucolipotoxicity-induced oxidative stress and mitochondrial dysfunction of pancreatic β-cells are one of the mechanisms that have been related to the low insulin secretion and cell death during diabetes development. In early or non-chronic stages, the pancreatic β-cells respond to hyperglycemia or hyperlipidemia, stimulating insulin secretion. However, the chronic effect of both leads to the establishment of glucolipotoxicity which induces constant overstimulation of pancreatic β-cells, a condition that leads to cell death by apoptosis. The mechanism described, at this moment, is the accelerated mitochondrial dysfunction triggered by the high production of reactive oxygen species (ROS) due to excess nutrients. At first, mitochondria respond to over-nutrition accelerating oxygen consumption and consequently increasing the ATP synthesis. A permanent increase of ATP/ADP ratio leads to a constant inhibition of K+ ATP-channel and therefore a continuous insulin secretion accompanied by an increase in ROS. Finally, ROS accumulation compromises mitochondrial function due to the uncontrolled oxidation of proteins, lipids, and DNA generating functional alterations such as a drop of membrane potential, deregulation of mitochondrial dynamics, low rate of ATP synthesis and consequently the cell death. This review aims to describe the effect of glucolipotoxicity-induced oxidative stress and its relationship with mitochondrial dysfunction in β-cell during type 2 diabetes development.

scholarly journals Long-Term Exposure of Pancreatic β-Cells to Palmitate Results in SREBP-1C-Dependent Decreases in GLP-1 Receptor Signaling via CREB and AKT and Insulin Secretory Response

Endocrinology ◽  
2016 ◽  
Vol 157 (6) ◽  
pp. 2243-2258 ◽  
Author(s):  
Annalisa Natalicchio ◽  
Giuseppina Biondi ◽  
Nicola Marrano ◽  
Rossella Labarbuta ◽  
Federica Tortosa ◽  
...  
Keyword(s):  
Protein Expression ◽  
Insulin Release ◽  
Binding Protein ◽  
Camp Response Element Binding ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Camp Response Element ◽  
Element Binding Protein ◽  
Viral Oncogene Homolog ◽  
Erk Kinase

The effects of prolonged exposure of pancreatic β-cells to high saturated fatty acids on glucagon-like peptide-1 (GLP-1) action were investigated. Murine islets, human pancreatic 1.1B4 cells, and rat INS-1E cells were exposed to palmitate for 24 hours. mRNA and protein expression/phosphorylation were measured by real-time RT-PCR and immunoblotting, respectively. Specific short interfering RNAs were used to knockdown expression of the GLP-1 receptor (Glp1r) and Srebf1. Insulin release was assessed with a specific ELISA. Exposure of murine islets, as well as of human and INS-1E β-cells, to palmitate reduced the ability of exendin-4 to augment insulin mRNA levels, protein content, and release. In addition, palmitate blocked exendin-4-stimulated cAMP-response element-binding protein and v-akt murine thymoma viral oncogene homolog phosphorylation, whereas phosphorylation of MAPK-ERK kinase-1/2 and ERK-1/2 was not altered. Similarly, RNA interference-mediated suppression of Glp1r expression prevented exendin-4-induced cAMP-response element-binding protein and v-akt murine thymoma viral oncogene homolog phosphorylation, but did not impair exendin-4 stimulation of MAPK-ERK kinase-1/2 and ERK-1/2. Both islets from mice fed a high fat diet and human and INS-1E β-cells exposed to palmitate showed reduced GLP-1 receptor and pancreatic duodenal homeobox-1 (PDX-1) and increased sterol regulatory element-binding protein (SREBP-1C) mRNA and protein levels. Furthermore, suppression of SREBP-1C protein expression prevented the reduction of PDX-1 and GLP-1 receptor levels and restored exendin-4 signaling and action. Finally, treatment of INS-1E cells with metformin for 24 h resulted in inhibition of SREBP-1C expression, increased PDX-1 and GLP-1 receptor levels, consequently, enhancement of exendin-4-induced insulin release. Palmitate impairs exendin-4 effects on β-cells by reducing PDX-1 and GLP-1 receptor expression and signaling in a SREBP-1C-dependent manner. Metformin counteracts the impairment of GLP-1 receptor signaling induced by palmitate.

Abstract 294: Expression of Matrix Metalloproteases during the Differentiation of Porcine Adopse-Drived Mesenchymal Stem Cells ro Endothelial Cells

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Sami G Almalki ◽  
Velidi Rao ◽  
Divya Pankajakshan ◽  
Devendra K Agrawal
Keyword(s):  
Stem Cells ◽  
Endothelial Cells ◽  
Mesenchymal Stem Cells ◽  
Enzyme Activity ◽  
Protein Expression ◽  
Western Blot ◽  
Gelatin Zymography ◽  
Matrix Metalloproteases ◽  
Positive Staining ◽  
Mrna Transcripts

Rationale Adipose-derived mesenchymal stem cells (ADMSCs) are multipotent cells that have the potential to differentiate into different cell linages, and represent promising tools in various clinical applications. However, the molecular mechanisms that control the ability of ADMSCs to remodel 3-dimensional extracellular matrix (ECM) barriers during differentiation are not clearly understood. Herein, we studied the expression of matrix metalloproteinases (MMPs) during the differentiation of ADMSCs to endothelial cells (ECs) in vitro . Methods MSCs were isolated from porcine abdominal adipose tissue, and characterized by positive staining for MSC markers, CD44, CD73, CD90, and negative staining for CD11b, CD34 and CD45. The plasticity of MSCs was detected by bi-lineage differentiation to osteocytes, and adipocytes. The mRNA transcripts for different MMPs and TIMPs and protein expression of EC markers were analyzed by RT-PCR and immunostaining. The enzyme activity and protein expression were also analyzed by gelatin zymography, ELISA, and Western blot. Results The differentiation of ADMSCs to ECs was confirmed by the positive staining and mRNA expression of the endothelial markers. The mRNA transcripts for MMP-2 and membrane type 1 MMP (MT1-MMP) was significantly increased by 2.5 and 2.0 fold, respectively, during the differentiation of MSCs into ECs. Western blot and ELISA showed an elevated MT1-MMP and MMP-2 expression. The enzyme activity of MMP-2 was also observed by gelatin zymography. Conclusion We demonstrated that porcine ADMSCs have the ability to differentiate into ECs, and this process involves the up-regulation of MMP-2 and MT1-MMP. The increase in the expression of MMP-2 and MT1-MMP may, at least partially, facilitate the change in morphology of MSCs by degrading the ECM barriers. These findings may provide a potential mechanism for the role of MMP2 and MT1-MMP in the differentiation of ADMSCs into ECs.

scholarly journals Hypoxia reduces HNF4α/MODY1 protein expression in pancreatic β-cells by activating AMP-activated protein kinase

2017 ◽  
Vol 292 (21) ◽  
pp. 8716-8728 ◽  
Author(s):  
Yoshifumi Sato ◽  
Tomonori Tsuyama ◽  
Chinami Sato ◽  
Md. Fazlul Karim ◽  
Tatsuya Yoshizawa ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Protein Expression ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Amp Activated Protein Kinase

scholarly journals Vescalagin from Pink Wax Apple (Syzygium samarangense (Blume) Merrill and Perry) Protects Pancreatic β-Cells against Methylglyoxal-Induced Inflammation in Rats

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1448
Author(s):  
Wen-Chang Chang ◽  
James Swi-Bea Wu ◽  
Szu-Chuan Shen
Keyword(s):  
Protein Expression ◽  
Diabetic Rats ◽  
Related Factor ◽  
Advanced Glycation ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Expression Levels ◽  
Enhancer Binding Protein ◽  
Glycation End Products ◽  
Mitogen Activated Protein

Methylglyoxal (MG) is the primary precursor of advanced glycation end products involved in the pathogenesis of inflammation and diabetes. A previous study in our laboratory found anti-inflammatory and anti-hyperglycemic effects of the polyphenol vescalagin (VES) in rats with MG-induced carbohydrate metabolic disorder. The present study further investigated the occurrence of inflammation in pancreatic β-cells in MG-induced diabetic rats and the mechanism by which VES prevents it. The results showed that VES downregulates the protein expression levels of advanced glycation end product receptors and CCAAT/enhancer binding protein-β and upregulates the protein expression levels of pancreatic duodenal homeobox-1, nuclear factor erythroid 2-related factor 2 and glyoxalase I from the pancreatic cells. The results also revealed that VES elevates glutathione and antioxidant enzyme contents and then downregulates c-Jun N-terminal kinase and p38 mitogen-activated protein kinases pathways to protect pancreatic β-cells in MG-administered rats.

scholarly journals Phagocyte-like NADPH oxidase promotes cytokine-induced mitochondrial dysfunction in pancreatic β-cells: evidence for regulation by Rac1

2011 ◽  
Vol 300 (1) ◽  
pp. R12-R20 ◽  
Author(s):  
Wasanthi Subasinghe ◽  
Ismail Syed ◽  
Anjaneyulu Kowluru
Keyword(s):  
Nadph Oxidase ◽  
Mitochondrial Dysfunction ◽  
Caspase 3 ◽  
Primary Source ◽  
Significant Loss ◽  
Ros Generation ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Subunit Expression ◽  
Cellular Signal

Reactive oxygen species (ROS) are important mediators of cellular signal transduction cascades such as proliferation, migration, and apoptosis. Chronic exposure of isolated β-cells to proinflammatory cytokines elevates intracellular oxidative stress leading to the demise of pancreatic β-cells culminating in the onset of diabetes. Although the mitochondrial electron transport chain is felt to be the primary source of ROS, several lines of recent evidence suggest that phagocyte-like NADPH oxidase plays a central role in cytokine-mediated ROS generation and apoptosis of β-cells. However, the precise mechanisms underlying the regulation of NADPH oxidase remain unknown. To address this, insulin-secreting INS 832/13 cells were treated with cytomix (IL-1β, IFN-γ, and TNF-α; 10 ng/ml each) for different time intervals (0–24 h). A significant, time-dependent increase in NADPH oxidase activation/intracellular ROS production, p47phox subunit, but not p67phox subunit, expression of the phagocyte-like NADPH oxidase were demonstrable under these conditions. Furthermore, siRNA-p47phox transfection or exposure of INS 832/13 cells to apocynin, a selective inhibitor of NADPH oxidase, markedly attenuated cytomix-induced ROS generation in these cells. Cytomix-mediated mitochondrial dysfunction in INS 832/13 cells was evident by a significant loss of mitochondrial membrane potential (MMP) and upregulated caspase 3 activity. Cytomix treatment also caused a transient (within 15 min) activation of Rac1, a component of the NADPH oxidase holoenzyme. Furthermore, GGTI-2147 and NSC23766, known Rac1 inhibitors, not only attenuated the cytomix-induced Rac1 activation but also significantly prevented loss of MMP (NSC23766 > GGTI-2147). However, NSC23766 had no effect on cytomix-induced NO generation or caspase 3 activation, suggesting additional regulatory mechanisms might underlie these signaling steps. Together, these findings suggested that Rac1-mediated regulation of phagocyte-like NADPH oxidase contributes to cytokine-mediated mitochondrial dysfunction in the β-cell.

scholarly journals The Coffee Diterpene, Kahweol, Ameliorates Pancreatic β-Cell Function in Streptozotocin (STZ)-Treated Rat INS-1 Cells through NF-kB and p-AKT/Bcl-2 Pathways

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5167
Author(s):  
Waseem El-Huneidi ◽  
Shabana Anjum ◽  
Khuloud Bajbouj ◽  
Eman Abu-Gharbieh ◽  
Jalal Taneera
Keyword(s):  
Insulin Secretion ◽  
Cell Viability ◽  
Glucose Uptake ◽  
B Cell Lymphoma ◽  
Heme Oxygenase 1 ◽  
Ros Production ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Antioxidant Proteins ◽  
The Impact

Kahweol is a diterpene molecule found in coffee that exhibits a wide range of biological activity, including anti-inflammatory and anticancer properties. However, the impact of kahweol on pancreatic β-cells is not known. Herein, by using clonal rat INS-1 (832/13) cells, we performed several functional experiments including; cell viability, apoptosis analysis, insulin secretion and glucose uptake measurements, reactive oxygen species (ROS) production, as well as western blotting analysis to investigate the potential role of kahweol pre-treatment on damage induced by streptozotocin (STZ) treatment. INS-1 cells pre-incubated with different concentrations of kahweol (2.5 and 5 µM) for 24 h, then exposed to STZ (3 mmol/L) for 3 h reversed the STZ-induced effect on cell viability, apoptosis, insulin content, and secretion in addition to glucose uptake and ROS production. Furthermore, Western blot analysis showed that kahweol downregulated STZ-induced nuclear factor kappa B (NF-κB), and the antioxidant proteins, Heme Oxygenase-1 (HMOX-1), and Inhibitor of DNA binding and cell differentiation (Id) proteins (ID1, ID3) while upregulated protein expression of insulin (INS), p-AKT and B-cell lymphoma 2 (BCL-2). In conclusion, our study suggested that kahweol has anti-diabetic properties on pancreatic β-cells by suppressing STZ induced apoptosis, increasing insulin secretion and glucose uptake. Targeting NF-κB, p-AKT, and BCL-2 in addition to antioxidant proteins ID1, ID3, and HMOX-1 are possible implicated mechanisms.

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