Activation of the NLRP3 inflammasome by CCl4 exacerbates hepatopathogenic diet-induced experimental NASH

• Published in: Annals of hepatology Vol. 28; no. 1; p. 100780
• Main Authors: Vargas-Pozada, Eduardo E., Ramos-Tovar, Erika, Rodriguez-Callejas, Juan D., Cardoso-Lezama, Irina, Galindo-Gómez, Silvia, Gil-Becerril, Karla, Vásquez-Garzón, Verónica Rocío, Arellanes-Robledo, Jaime, Tsutsumi, Víctor, Villa-Treviño, Saúl, Muriel, Pablo
• Format: Journal Article
• Language: English
• Published: Elsevier España, S.L.U 01.01.2023; Elsevier
• Subjects: CCl4; Fibrosis; Inflammation; NASH; NLRP3 inflammasome; Nonalcoholic steatohepatitis; glutathione; metalloproteinase; nuclear factor kappa B; alanine aminotransferase; phosphate-buffered saline; tris-buffered saline with 0.1% Tween-20; NLRP3 inflammasome; adapter protein apoptosis-associated speck-like protein containing a caspase recruitment domain; mitogen-activated protein kinase; transforming growth factor-beta; tumor necrosis factor-alpha; Nonalcoholic steatohepatitis; carboxymethyl cellulose; high-fat; peroxisome proliferator-activated receptor alpha; red oil O; reactive oxygen species; gamma-glutamyl transpeptidase; alkaline phosphatase; immunohistochemistry; malondialdehyde; transmission electron microscopy; interleukin; hepatocellular carcinoma; immunofluorescence; hematoxylin and eosin; extracellular signal-regulated kinases; thiobarbituric acid; Inflammation; carbon tetrachloride; nucleotide-binding domain leucine-rich-containing family; NASH; lipid peroxidation; smooth muscle alpha-actin; c-Jun N-terminal kinases; 4-hydroxynonenal; connective tissue growth factor; sterol regulatory element-binding protein 1C; CCl4; Fibrosis; standard error of the mean; nuclear factor erythroid 2-related factor 2; toll-like receptor 4; bovine serum albumin; trichloroacetic acid
• ISSN: 1665-2681; 2659-5982
• DOI: 10.1016/j.aohep.2022.100780

Administration of carbon tetrachloride (CCl4), along with an hepatopathogenic diet, is widely employed as a chemical inducer to replicate human nonalcoholic steatohepatitis (NASH) in rodents; however, the role of the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome in this model remains unclear. We aimed to determine the relevance of NLRP3 inflammasome activation in the development of NASH induced by CCl4 along with an hepatopathogenic diet in male Wistar rats. Animals were fed either a high fat, sucrose, and cholesterol diet (HFSCD) or a HFSCD plus intraperitoneal injections of low doses of CCl4 (400 mg/kg) once a week for 15 weeks. Liver steatosis, inflammation, fibrosis, and NLRP3 inflammasome activation were evaluated using biochemical, histological, ultrastructural, and immunofluorescence analyses, western blotting, and immunohistochemistry. Our experimental model reproduced several aspects of the human NASH pathophysiology. NLRP3 inflammasome activation was induced by the combined effect of HFSCD plus CCl4 and significantly increased levels of both proinflammatory and profibrogenic cytokines and collagen deposition in the liver; thus, NASH severity was higher in the HFSCD+CCl4 group than that in the HFSCD group, to which CCl4 was not administered. Hepatic stellate cells, the most profibrogenic cells, were activated by HFSCD plus CCl4, as indicated by elevated levels of α-smooth muscle actin. Thus, activation of the NLRP3 inflammasome, triggered by low doses of CCl4, exacerbates the severity of NASH. Our results indicate that NLRP3 inflammasome activation plays a key role and may be an important therapeutic target for NASH treatment.