Artemether Ameliorates Non-Alcoholic Steatohepatitis by Restraining Cross-Talk Between Lipotoxicity-Induced Hepatic Hepatocytes and Macrophages.

Non-alcoholic steatohepatitis (NASH) has no effective treatment drug. Our previous study initially found that artemether (Art) treatment significantly attenuates NSAH by regulating liver lipid metabolism. This study further elucidates new mechanisms of Art in improving liver inflammation and provides evidence for drug repurposing. Herein, we utilized HFHF diet-induced animal model and macrophage models to detect the mechanisms of Art in NASH. We confirmed that Art significantly reduced hepatic steatosis, injury, and fibrosis in a high-fat high-fructose (HFHF) diet-induced animal model. Art significantly suppressed the activation of inflammatory macrophages and secretion of pro-inflammatory cytokine (IL-1β) by reducing serum double-stranded DNA (dsDNA) levels and triggering the AIM2/Caspase-1/GSDMD signaling in vivo. dsDNA-induced Caspase-1 and PI-positive cells pyroptosis, AIM2 inflammasome activation, IL-1β, and IL-18 secretion increase were inhibited by Art in vitro. Furthermore, we found Art effectively suppressed mitochondrial DNA (mtDNA), a typical form of dsDNA, released from free fatty acid (FFA)-stressed hepatocytes, which further inhibited AIM2 inflammasome mediated-pyroptosis through decreasing the cleavage of Caspase-1/GSDMD/IL-1β. Moreover, inhibition of the AIM2 gene partly reversed the inhibitory effect of Art on macrophage pyroptosis. Impaired mitochondrial structure and function were confirmed in FFA-stressed hepatocytes and the HFHF-diet-induced NASH mouse model, which was reversed by Art treatment. The present study provides evidence for Art as a potential anti-pyroptosis therapeutic agent for NASH treatment.