Faculty Opinions recommendation of Metformin and resveratrol inhibit Drp1-mediated mitochondrial fission and prevent ER stress-associated NLRP3 inflammasome activation in the adipose tissue of diabetic mice.

2019 ◽  
Author(s):  
Paras Anand
Keyword(s):  
Adipose Tissue ◽  
Er Stress ◽  
Nlrp3 Inflammasome ◽  
Mitochondrial Fission ◽  
Inflammasome Activation ◽  
Diabetic Mice ◽  
Nlrp3 Inflammasome Activation

scholarly journals Eplerenone prevented obesity-induced inflammasome activation and glucose intolerance

2017 ◽  
Vol 235 (3) ◽  
pp. 179-191 ◽  
Author(s):  
Tsutomu Wada ◽  
Akari Ishikawa ◽  
Eri Watanabe ◽  
Yuto Nakamura ◽  
Yusuke Aruga ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Glucose Intolerance ◽  
Nlrp3 Inflammasome ◽  
Inflammasome Activation ◽  
M2 Macrophage ◽  
Expression Levels ◽  
Nlrp3 Inflammasome Activation ◽  
M1 Macrophage ◽  
Anti Inflammatory

Obesity-associated activation of the renin-angiotensin-aldosterone system is implicated in the pathogenesis of insulin resistance; however, influences of mineralocorticoid receptor (MR) inhibition remain unclear. Therefore, we aimed to clarify the anti-inflammatory mechanisms of MR inhibition using eplerenone, a selective MR antagonist, in C57BL/6 mice fed a high-fat diet (HFD) for 12 weeks. Eplerenone prevented excessive body weight gain and fat accumulation, ameliorated glucose intolerance and insulin resistance and enhanced energy metabolism. In the epididymal white adipose tissue (eWAT), eplerenone prevented obesity-induced accumulation of F4/80+CD11c+CD206−-M1-adipose tissue macrophage (ATM) and reduction of F4/80+CD11c−CD206+-M2-ATM. Interestingly, M1-macrophage exhibited lower expression levels of MR, compared with M2-macrophage, in the ATM of eWAT and in vitro-polarized bone marrow-derived macrophages (BMDM). Importantly, eplerenone and MR knockdown attenuated the increase in the expression levels of proIl1b, Il6 and Tnfa, in the eWAT and liver of HFD-fed mice and LPS-stimulated BMDM. Moreover, eplerenone suppressed IL1b secretion from eWAT of HFD-fed mice. To reveal the anti-inflammatory mechanism, we investigated the involvement of NLRP3-inflammasome activation, a key process of IL1b overproduction. Eplerenone suppressed the expression of the inflammasome components, Nlrp3 and Caspase1, in the eWAT and liver. Concerning the second triggering factors, ROS production and ATP- and nigericin-induced IL1b secretion were suppressed by eplerenone in the LPS-primed BMDM. These results indicate that eplerenone inhibited both the priming and triggering signals that promote NLRP3-inflammasome activation. Therefore, we consider MR to be a crucial target to prevent metabolic disorders by suppressing inflammasome-mediated chronic inflammation in the adipose tissue and liver under obese conditions.

scholarly journals NLRP3 Inflammasome Activation in Adipose Tissues and Its Implications on Metabolic Diseases

2020 ◽  
Vol 21 (11) ◽  
pp. 4184 ◽  
Author(s):  
Kelvin Ka-Lok Wu ◽  
Samson Wing-Ming Cheung ◽  
Kenneth King-Yip Cheng
Keyword(s):  
Adipose Tissue ◽  
Nlrp3 Inflammasome ◽  
Metabolic Disorders ◽  
Immune Cell ◽  
Diabetic Patients ◽  
Inflammasome Activation ◽  
Low Grade ◽  
Adipose Tissues ◽  
Adipose Tissue Dysfunction ◽  
Nlrp3 Inflammasome Activation

Adipose tissue is an active endocrine and immune organ that controls systemic immunometabolism via multiple pathways. Diverse immune cell populations reside in adipose tissue, and their composition and immune responses vary with nutritional and environmental conditions. Adipose tissue dysfunction, characterized by sterile low-grade chronic inflammation and excessive immune cell infiltration, is a hallmark of obesity, as well as an important link to cardiometabolic diseases. Amongst the pro-inflammatory factors secreted by the dysfunctional adipose tissue, interleukin (IL)-1β, induced by the NLR family pyrin domain-containing 3 (NLRP3) inflammasome, not only impairs peripheral insulin sensitivity, but it also interferes with the endocrine and immune functions of adipose tissue in a paracrine manner. Human studies indicated that NLRP3 activity in adipose tissues positively correlates with obesity and its metabolic complications, and treatment with the IL-1β antibody improves glycaemia control in type 2 diabetic patients. In mouse models, genetic or pharmacological inhibition of NLRP3 activation pathways or IL-1β prevents adipose tissue dysfunction, including inflammation, fibrosis, defective lipid handling and adipogenesis, which in turn alleviates obesity and its related metabolic disorders. In this review, we summarize both the negative and positive regulators of NLRP3 inflammasome activation, and its pathophysiological consequences on immunometabolism. We also discuss the potential therapeutic approaches to targeting adipose tissue inflammasome for the treatment of obesity and its related metabolic disorders.

scholarly journals Ethanol-activated CaMKII signaling induces neuronal apoptosis through Drp1-mediated excessive mitochondrial fission and JNK1-dependent NLRP3 inflammasome activation.

2019 ◽  
Author(s):  
Jae Ryong Lim ◽  
Hyun Jik Lee ◽  
Young Hyun Jung ◽  
Jun Sung Kim ◽  
Chang Woo Chae ◽  
...  
Keyword(s):  
Intracellular Calcium ◽  
Nlrp3 Inflammasome ◽  
Neuronal Apoptosis ◽  
Mitochondrial Dynamics ◽  
Mitochondrial Fission ◽  
Neuronal Cells ◽  
Calcium Overload ◽  
Inflammasome Activation ◽  
Nlrp3 Inflammasome Activation ◽  
Ros Accumulation

Abstract Background: Neurodegeneration is a representative phenotype of patients with chronic alcoholism. Ethanol-induced calcium overload causes NLRP3 inflammasome formation and an imbalance in mitochondrial dynamics, closely associated with the pathogenesis of neurodegeneration. However, how calcium regulates this process in neuronal cells is poorly understood. Therefore, the present study investigated the detailed mechanism of calcium-regulated mitochondrial dynamics and NLRP3 inflammasome formation in neuronal cells by ethanol. Methods: In this study, we used the SK-N-MC human neuroblastoma cell line. To confirm the expression level of the mRNA and protein, real time quantitative PCR and western blot were performed. Co-immunoprecipitation and Immunofluorescence staining were conducted to confirm the complex formation or interaction of the proteins. Flow cytometry was used to analyze intracellular calcium, mitochondrial dysfunction and neuronal apoptosis. Results: Ethanol increased cleaved caspase-3 levels and mitochondrial reactive oxygen species (ROS) generation associated with neuronal apoptosis. In addition, ethanol increased PKA activation and CREB phosphorylation, which increased NMDA receptor (NMDAR) expression. Ethanol-increased NMDAR induced intracellular calcium overload and CaMKII activation leading to phosphorylation of dynamin-related protein 1 (Drp1) and JNK1. Drp1 phosphorylation promoted Drp1 translocation to the mitochondria, resulting in excessive mitochondrial fission, mitochondrial ROS accumulation, and loss of mitochondrial membrane potential, which was recovered by Drp1 inhibitor pretreatment. Ethanol-induced JNK1 phosphorylation activated the NLRP3 inflammasome that induced caspase-1 dependent mitophagy inhibition, thereby exacerbating ROS accumulation and causing cell death. Suppressing caspase-1 induced mitophagy and reversed the ethanol-induced apoptosis in neuronal cells. Conclusions: Our results demonstrated that ethanol upregulated NMDAR-dependent CaMKII phosphorylation which is essential for Drp1-mediated excessive mitochondrial fission and the JNK1-induced NLRP3 inflammasome activation resulting in neuronal apoptosis.

scholarly journals Ethanol-activated CaMKII signaling induces neuronal apoptosis through Drp1-mediated excessive mitochondrial fission and JNK1-dependent NLRP3 inflammasome activation.

2020 ◽  
Author(s):  
Jae Ryong Lim ◽  
Hyun Jik Lee ◽  
Young Hyun Jung ◽  
Jun Sung Kim ◽  
Chang Woo Chae ◽  
...  
Keyword(s):  
Intracellular Calcium ◽  
Nlrp3 Inflammasome ◽  
Neuronal Apoptosis ◽  
Mitochondrial Dynamics ◽  
Mitochondrial Fission ◽  
Neuronal Cells ◽  
Calcium Overload ◽  
Inflammasome Activation ◽  
Nlrp3 Inflammasome Activation ◽  
Ros Accumulation

Abstract Background: Neurodegeneration is a representative phenotype of patients with chronic alcoholism. Ethanol-induced calcium overload causes NLRP3 inflammasome formation and an imbalance in mitochondrial dynamics, closely associated with the pathogenesis of neurodegeneration. However, how calcium regulates this process in neuronal cells is poorly understood. Therefore, the present study investigated the detailed mechanism of calcium-regulated mitochondrial dynamics and NLRP3 inflammasome formation in neuronal cells by ethanol. Methods: In this study, we used the SK-N-MC human neuroblastoma cell line. To confirm the expression level of the mRNA and protein, real time quantitative PCR and western blot were performed. Co-immunoprecipitation and Immunofluorescence staining were conducted to confirm the complex formation or interaction of the proteins. Flow cytometry was used to analyze intracellular calcium, mitochondrial dysfunction and neuronal apoptosis. Results: Ethanol increased cleaved caspase-3 levels and mitochondrial reactive oxygen species (ROS) generation associated with neuronal apoptosis. In addition, ethanol increased PKA activation and CREB phosphorylation, which increased NMDA receptor (NMDAR) expression. Ethanol-increased NMDAR induced intracellular calcium overload and CaMKII activation leading to phosphorylation of dynamin-related protein 1 (Drp1) and JNK1. Drp1 phosphorylation promoted Drp1 translocation to the mitochondria, resulting in excessive mitochondrial fission, mitochondrial ROS accumulation, and loss of mitochondrial membrane potential, which was recovered by Drp1 inhibitor pretreatment. Ethanol-induced JNK1 phosphorylation activated the NLRP3 inflammasome that induced caspase-1 dependent mitophagy inhibition, thereby exacerbating ROS accumulation and causing cell death. Suppressing caspase-1 induced mitophagy and reversed the ethanol-induced apoptosis in neuronal cells. Conclusions: Our results demonstrated that ethanol upregulated NMDAR-dependent CaMKII phosphorylation which is essential for Drp1-mediated excessive mitochondrial fission and the JNK1-induced NLRP3 inflammasome activation resulting in neuronal apoptosis.

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