scholarly journals NLRP3 inflammasome activation is involved in Ang II-induced kidney damage via mitochondrial dysfunction

Oncotarget ◽  
2016 ◽  
Vol 7 (34) ◽  
pp. 54290-54302 ◽  
Author(s):  
Yi Wen ◽  
Yiran Liu ◽  
Taotao Tang ◽  
Linli Lv ◽  
Hong Liu ◽  
...  
2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yu Chen ◽  
Meiying Zeng ◽  
Yang Zhang ◽  
Hui Guo ◽  
Wei Ding ◽  
...  

Inflammation has been considered a key component in the pathogenesis and progression of angiotensin II- (Ang II-) induced cardiac hypertrophy and related cardiomyopathy. As a vital mediator of inflammation, the role of the Nlrp3 inflammasome in Ang II-induced cardiomyopathy remains unclear. This study was aimed to determine whether Nlrp3 inflammasome activation and its downstream pathway were involved in Ang II-induced cardiomyopathy. We established an Ang II infusion model in both wild-type and Nlrp3-/- mice to determine the contribution of Nlrp3 to cardiac function. Cardiac fibrosis was determined by Masson’s trichrome staining, real-time PCR, and TUNEL assay; cardiac function was assessed by echocardiography. Nlrp3 inflammasome activation and related downstream cytokines were measured by Western blotting and enzyme-linked immunosorbent assays; mitochondrial dysfunction was examined by transmission electron microscopy and real-time PCR. We found that Ang II-infused mice showed impaired cardiac function, as evidenced by increased cardiac fibrosis, apoptosis, inflammation, and left ventricular dysfunction. However, these alterations were significantly alleviated in the mice with Nlrp3 gene deletion. Moreover, Ang II-infused mice showed increased Nlrp3 inflammasome activity relative to that of the cytokines IL-1β and IL-18, increased reactive oxygen species, mitochondrial abnormalities, and decreased mtDNA copy number and ATP synthase activity. These molecular and pathological alterations were also attenuated in Nlrp3 deficient mice. In conclusion, Nlrp3 inflammasome-induced mitochondrial dysfunction is involved in Ang II-induced cardiomyopathy. Nlrp3 gene deletion attenuated mitochondrial abnormalities, cardiac inflammation, oxidative stress, and fibrosis and thus alleviated heart dysfunction and hypertrophy. Targeting the Nlrp3 inflammasome and/or mitochondria may be a therapeutic approach for Ang II-induced cardiac diseases.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Vivek Verma ◽  
Parveen Kumar ◽  
Surbhi Gupta ◽  
Sonal Yadav ◽  
Rakesh Singh Dhanda ◽  
...  

2021 ◽  
pp. 1-13
Author(s):  
Mingzhu Jiang ◽  
Min Zhao ◽  
Mi Bai ◽  
Juan Lei ◽  
Yanggang Yuan ◽  
...  

Background: Podocyte injury contributes to progressive glomerulosclerosis. Previously, we demonstrated the important role of the NLR family pyrin domain containing 3 (NLRP3) inflammasome in mediating the podocyte injury induced by aldosterone. Silent mating type information regulation 2 homolog 1 (SIRT1) is an NAD+-dependent deacetylase that is associated with the regulation of cellular inflammation. However, whether the activation of the NLRP3 inflammasome in podocytes is regulated by SIRT1, and the mechanism involved, remains unknown. Methods: In this study, we detected SIRT1 expression in patients with podocyte disease and performed an aldosterone infusion model in podocyte-specific Sirt1 knockout mice. In cultured podocytes, we used plasmids to overexpress SIRT1 and treated the podocyte with aldosterone. Results: SIRT1 was significantly decreased in the glomeruli of patients with podocyte disease. Sirt1-deficient mice showed significant urinary albumin excretion after aldosterone infusion, and the severity of the glomerular injury was significantly greater in podocyte-specific Sirt1 knockout mice than in the wild-type mice. Moreover, podocyte conditional Sirt1 knockout aggravated NLRP3 inflammasome activation and mitochondrial dysfunction (MtD). In vitro, overexpression of SIRT1 inhibited NLRP3 activation, protected against MtD and podocyte injury. Conclusion: Taken together, these findings revealed a novel regulatory mechanism of the NLRP3 inflammasome by SIRT1 by promoting mitochondrial function, which provides some potential targets for the treatment of glomerular diseases.


2021 ◽  
Vol 12 ◽  
Author(s):  
Liu Ye ◽  
Qi Zeng ◽  
Maoyao Ling ◽  
Riliang Ma ◽  
Haishao Chen ◽  
...  

RationaleDisruption of intracellular calcium (Ca2+) homeostasis is implicated in inflammatory responses. Here we investigated endoplasmic reticulum (ER) Ca2+ efflux through the Inositol 1,4,5-trisphosphate receptor (IP3R) as a potential mechanism of inflammatory pathophysiology in a ventilator-induced lung injury (VILI) mouse model.MethodsC57BL/6 mice were exposed to mechanical ventilation using high tidal volume (HTV). Mice were pretreated with the IP3R agonist carbachol, IP3R inhibitor 2-aminoethoxydiphenyl borate (2-APB) or the Ca2+ chelator BAPTA-AM. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected to measure Ca2+ concentrations, inflammatory responses and mRNA/protein expression associated with ER stress, NLRP3 inflammasome activation and inflammation. Analyses were conducted in concert with cultured murine lung cell lines.ResultsLungs from mice subjected to HTV displayed upregulated IP3R expression in ER and mitochondrial-associated-membranes (MAMs), with enhanced formation of MAMs. Moreover, HTV disrupted Ca2+ homeostasis, with increased flux from the ER to the cytoplasm and mitochondria. Administration of carbachol aggravated HTV-induced lung injury and inflammation while pretreatment with 2-APB or BAPTA-AM largely prevented these effects. HTV activated the IRE1α and PERK arms of the ER stress signaling response and induced mitochondrial dysfunction-NLRP3 inflammasome activation in an IP3R-dependent manner. Similarly, disruption of IP3R/Ca2+ in MLE12 and RAW264.7 cells using carbachol lead to inflammatory responses, and stimulated ER stress and mitochondrial dysfunction.ConclusionIncrease in IP3R-mediated Ca2+ release is involved in the inflammatory pathophysiology of VILI via ER stress and mitochondrial dysfunction. Antagonizing IP3R/Ca2+ and/or maintaining Ca2+ homeostasis in lung tissue represents a prospective treatment approach for VILI.


2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Bing Zhou ◽  
Yun Qiu ◽  
Nan Wu ◽  
Ai-Dong Chen ◽  
Hong Zhou ◽  
...  

Vascular oxidative stress and inflammation play a major role in vascular diseases. This study was aimed at determining the protective roles of fibronectin type III domain-containing 5 (FNDC5) in angiotensin II- (Ang II-) induced vascular oxidative stress and inflammation and underlying mechanisms. Wild-type (WT) and FNDC5-/- mice, primary mouse vascular smooth muscle cells (VSMCs), and the rat aortic smooth muscle cell line (A7R5) were used in the present study. Subcutaneous infusion of Ang II caused more serious hypertension, vascular remodeling, oxidative stress, NLRP3 inflammasome activation, AMPK phosphorylation inhibition, and SIRT1 downregulation in the aorta of FNDC5-/- mice than those of WT mice. Exogenous FNDC5 attenuated Ang II-induced superoxide generation, NADPH oxidase 2 (NOX2) and NLRP3 upregulation, mature caspase-1, and interleukin-1β (IL-1β) production in A7R5 cells. The protective roles of FNDC5 were prevented by SIRT-1 inhibitor EX527, AMPK inhibitor compound C, or integrin receptor inhibitor GLPG0187. FNDC5 attenuated the Ang II-induced inhibition in SIRT1 activity, SIRT1 protein expression, and AMPKα phosphorylation in A7R5 cells, which were prevented by compound C, EX527, and GLPG0187. FNDC5 deficiency deteriorated Ang II-induced oxidative stress, NLRP3 inflammasome activation, AMPK phosphorylation inhibition, and SIRT1 downregulation in primary aortic VSMCs of mice, which were prevented by exogenous FNDC5. These results indicate that FNDC5 deficiency aggravates while exogenous FNDC5 alleviates the Ang II-induced vascular oxidative stress and NLRP3 inflammasome activation via the AMPK-SIRT1 signal pathway in VSMCs.


2021 ◽  
Author(s):  
Lin-Shuang Zhang ◽  
Jin-Sheng Zhang ◽  
Yue-Long Hou ◽  
Wei-Wei Lu ◽  
Xian-Qiang Ni ◽  
...  

Abstract Intermedin (IMD), a paracrine/autocrine peptide, protects against cardiac fibrosis. However, the underlying mechanism remains poorly understood. Previous study reports that activation of Nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome contributed to cardiac fibrosis. In this study, we aimed to investigate whether IMD mitigates cardiac fibrosis by inhibiting NLRP3. Cardiac fibrosis was induced by angiotensin II (Ang II) infusion for 2 weeks in rats. Western blot, real-time PCR, histological staining, immunofluorescence assay, RNA sequencing, echocardiography and hemodynamics were used to detect the role and the mechanism of IMD in cardiac fibrosis. Ang II infusion resulted in rat cardiac fibrosis, shown as over-deposition of myocardial interstitial collagen and cardiac dysfunction. Importantly, NLRP3 activation and endoplasmic reticulum stress (ERS) was found in Ang II treated rat myocardium. Ang II infusion decreased the expression of IMD and increased the expression of the receptor system of IMD in the fibrotic rat myocardium. IMD treatment attenuated the cardiac fibrosis and improved cardiac function. In addition, IMD inhibited the upregulation of NLRP3 markers and ERS markers induced by Ang II. In vitro, IMD knockdown by small interfering RNA significantly promoted the Ang II-induced cardiac fibroblast and NLRP3 activation. Moreover, silencing of inositol requiring enzyme 1 α (IRE1α) blocked the effects of IMD inhibiting fibroblast and NLRP3 activation. Pre-incubation with PKA pathway inhibitor H89 blocked the effects of IMD on the anti-ERS, anti-NLRP3 and anti-fibrotic response. In conclusion, IMD alleviates cardiac fibrosis by inhibiting NLRP3 inflammasome activation via suppressing IRE1α and cAMP/PKA pathway.


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