Impact of IRS-2 on the regulation of hepatocyte pyroptosis via the PI3K/AKT pathway

Abstract

Abstract: Objective To explore the role and molecular mechanism of insulin receptor substrate (IRS) -2 in hydrogen peroxide (H₂O₂)-induced hepatocyte pyrotosis. Methods HepG2 and L02 cells were stimulated with H₂O₂, and the expressions of IRS-2 and pyroptosis-related proteins were assessed by Western blot analysis. IRS-2 siRNA was synthesized and employed to suppress the expression of IRS-2 gene in both HepG2 and L02 cell lines. The expression levels of IRS-2 and pyroptosis-related proteins were subsequently evaluated using Western blot analysis. Cell viability was determined using the CCK-8 assay, while changes in mitochondrial membrane potential were analyzed via flow cytometry. Cell morphology, mitochondria structure, and pyroptosomes were visualized under an electron microscope, with mitochondria morphology and quantity observed using Mito-Track Green staining. HepG2 and L02 cells were treated with IRS-2 siRNA alone or in combination with a PI3K/AKT pathway agonist to assess the expression levels of PI3K/AKT pathway proteins and pyroptosis-related proteins, Data analysis was conducted using independent sample t tests or one-way analysis of variance(ANOVA) where appropriate. Results In comparison to the control group, exposure to H₂O₂ led to decreased viability of hepatocytes, downregulated expression of IRS-2 protein, and increased expression of pyroptosis-related proteins. Reduced expression of IRS-2 resulted in mitochondrial dysfunction, disrupted hepatocyte morphology, increased pyroptosome numbers, and up-regulate expression of pyroptosis-related proteins. Additionally, the ratio of P-PI3K/PI3K and P-AKT/AKT was decreased. Activation of the PI3K/AKT pathway reversed the expression of pyroptosis-related proteins induced by IRS-2 downregulation. Conclusion Stimulation with H₂O₂ can decrease the expression of IRS-2 protein and induce pyroptosis in hepatocytes. Inhibiting IRS-2 expression may induce mitochondrial dysfunction by reducing PI3K/AKT pathway activation, ultimately leading to hepatocyte pyroptosis.

Key words: IRS-2, PI3K/AKT pathway, Pyroptosis, Hepatocyte, Mitochondrial dysfunction

GUO Qing-xin, YAO Ting, SHEN Le-er, CHEN Jin-mei, HU Wei-wei, ZHANG Yi, CHEN Xiao-hua. Impact of IRS-2 on the regulation of hepatocyte pyroptosis via the PI3K/AKT pathway[J]. Chinese Hepatolgy, 2024, 29(5): 561-566.

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