Rutaecarpine Attenuates Hepatic Lipid Accumulation and Oxidative Stress by Activating Autophagy Through the <scp>AMPK</scp> / <scp>ULK1</scp> Pathway

Non-alcoholic fatty liver disease (NAFLD) is a prevalent metabolic disorder disease in modern society, primarily caused by abnormal fat accumulation in the liver. This study aims to uncover the effects and potential mechanisms by which Rutaecarpine (Rut) alleviates lipid accumulation and oxidative damage in hepatocytes. Oleic acid and palmitic acid were used to induce lipid accumulation in AML12 cells, and Tyloxapol was used to induce hepatic lipid accumulation in mice. Then, various concentrations of Rut were administered. The mechanisms were further explored by using the Nrf2 inhibitor ML385, the AMPK inhibitor compound C (CC), and the autophagy inhibitor chloroquine. Additionally, computer simulations were employed to analyze the binding capacity of Rut to AMPK subunits. The study revealed that Rut significantly reduces lipid content and enhances the phosphorylation levels of AMPKα and Nrf2 expression. Crucially, the AMPK inhibitor CC markedly diminished Rut's antioxidant and lipid-lowering effects. The study also identified that Rut promotes non-canonical activation of Nrf2 protein by regulating autophagy-related processes, although this effect was inhibited by CC. Furthermore, computer simulations demonstrated that Rut has a strong binding affinity for AMPK subunits, indicating that Rut may promote AMPK activation through potential specific subunit interactions. In summary, Rut alleviates lipid accumulation and oxidative stress by promoting activation of the AMPK/ULK1 signaling pathway and autophagy, providing foundational theoretical and experimental support for its potential application in treating lipid metabolic disorders.