Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common metabolic disease of the liver, characterized by hepatic steatosis in more than 5% of hepatocytes. However, despite the recent approval of the first drug, resmetirom, for the management of metabolic dysfunction-associated steatohepatitis, decades of target exploration and hundreds of clinical trials have failed, highlighting the urgent need to find new druggable targets for the discovery of innovative drug candidates against MASLD. Here, we found that glutathione S-transferase alpha 1 (GSTA1) expression was negatively associated with lipid droplet accumulation in vitro and in vivo. Overexpression of GSTA1 significantly attenuated oleic acid-induced steatosis in hepatocytes or high-fat diet-induced steatosis in the mouse liver. The hepatoprotective and anti-inflammatory drug bicyclol also attenuated steatosis by upregulating GSTA1 expression. A detailed mechanism showed that GSTA1 directly interacts with fatty acid binding protein 1 (FABP1) and facilitates the degradation of FABP1, thereby inhibiting intracellular triglyceride synthesis by impeding the uptake and transportation of free fatty acids. Conclusion: GSTA1 may be a good target for the discovery of innovative drug candidates as GSTA1 stabilizers or enhancers against MASLD.
Background: The 2023 Delphi consensus defined metabolic and alcohol-associated liver disease (MetALD), distinguishing between alcohol abuse and moderate consumption. Although alcohol abuse is known to accelerate fatty liver disease progression, the health effects of chronic moderate alcohol intake under different dietary conditions remain unclear. This study aimed to evaluate the impact of moderate alcohol consumption on metabolic phenotypes and gut microbiota/metabolites in lean and obese mice and to propose a model approximating MetALD features. Methods: C57BL/6J mice were fed either a low-fat diet (LFD) or a high-fat diet (HFD) for 12 weeks, with access to 10% (v/v) alcohol in drinking water. Systemic metabolic parameters, liver histopathology, inflammatory and fibrotic markers, gut microbiota composition, and the fecal metabolome were assessed. Results: In LFD-fed mice, 10% alcohol intake induced multiple metabolic alterations, including elevated serum triglycerides, reduced fasting blood glucose, and changes in hepatic lipid metabolism along with steatosis and inflammation—though further studies are required to confirm causality. When combined with HFD, alcohol did not significantly exacerbate most glucose/lipid metabolic disorders but markedly increased hepatic inflammatory cell infiltration and fibrosis progression. Alcohol consistently increased gut microbial α-diversity in both dietary groups, while downregulating beneficial metabolites such as amino acids (e.g., glutamine, histidine), their derivatives, and short-chain fatty acids. Correlation analyses associated these microbial and metabolic changes with altered amino acid/cholesterol metabolism and inflammatory/fibrotic phenotypes, particularly under HFD conditions. Conclusions: These findings suggest that chronic moderate alcohol intake presents distinct risks in lean and obese individuals with different dietary structures.
The bark of Myrica rubra (Lour.) Siebold & Zucc (M. rubra) is a natural remedy widely used in China and other Asian countries to treat tissue and bone injuries, burns, scalds, gastrointestinal ulcers, and diarrhea. Myricanol is an important ingredient in the bark of M. rubra. This review summarizes articles published over the past 26 years on the pharmacological effects and mechanisms of action of myricanol, aiming to advance research and applications of myricanol. Evidence shows that myricanol has multiple bioactive properties, including antioxidant, anticancer, anti-inflammatory, antimicrobial, antidiabetic, and antihyperlipidemic effects. Myricanol improves metabolic abnormalities in mice by activating the AMPK/SIRT1/PGC-1α signaling pathway. It also demonstrates significant anticancer, antioxidant, and anti-inflammatory actions, primarily by regulating Caspase and BCL-2 family proteins, inhibiting iNOS expression, scavenging free radicals, and interacting with Peroxiredoxin 5. Therefore, myricanol shows great potential for the treatment of cancer, metabolic abnormalities, and inflammatory bowel disease. Further research is needed to improve its bioavailability, confirm its pharmacological effects and mechanisms in vivo, and explore its pharmacokinetic properties and safety.