Donepezil alleviates hepatic steatosis by mitigating ER stress via the AMPK/autophagy pathway

Donepezil (Do), a drug known for its ability to reduce neuronal inflammation and for its use in the treatment of Alzheimer's disease, has shown promise in combating hepatic lipid accumulation in hyperlipidemic conditions and endoplasmic reticulum (ER) stress, a factor associated with alterations in hepatic lipid metabolism. However, the mechanisms by which these problems are alleviated have not been fully elucidated. In this study, we investigated the effects of Do on hepatic lipid metabolism through both in vitro and in vivo studies. We examined the expression of proteins associated with lipogenesis and ER stress via immunoblot analysis, and hepatic lipid accumulation was assessed via oil red O staining. In addition, autophagosome formation was analyzed by counting MDC-positive cells. Our results demonstrated that Do treatment improved hepatic lipid metabolism and reduced the expression of ER stress markers, resulting in decreased lipogenic lipid deposition and apoptosis in the hepatocytes and livers of hyperlipidemic mice. Mechanistically, knocking down AMPK or inhibiting autophagy with 3-methyladenine (3 MA) attenuated the effects of Do on palmitate-exposed hepatocytes. These results suggest that Do alleviates hepatic ER stress via the AMPK/autophagy pathway and AMPK-mediated fatty acid oxidation, resulting in improved hepatic lipid metabolism and reduced hepatic steatosis and apoptosis. Our study provides evidence that Do may be a promising therapeutic approach for Alzheimer's disease patients with metabolic dysfunction-associated steatotic liver disease (MASLD).