Micheliolide Alleviates Hepatic Fibrosis by Inhibiting Autophagy in Hepatic Stellate Cells via the TrxR1/2-Mediated ROS/MEK/ERK Pathway.

Background: Hepatic fibrosis is a major global health issue without an optimal drug treatment, highlighting the urgent need to find effective therapies. This study aimed to clarify the role and mechanism of micheliolide in treating hepatic fibrosis. Methods: The efficacy of MCL was evaluated in a mouse model of CCl(4)-induced hepatic fibrosis. LX-2 cells were subjected to MCL treatment, and subsequent changes in fibrosis markers, autophagy, and the MEK/ERK pathway were analyzed using transcriptomics and Western blotting. The interaction between MCL and TrxR1 or TrxR2 were validated using cellular thermal shift assays (CETSA) and drug affinity responsive target stability (DARTS) assays. Results: Our findings indicated that MCL significantly alleviated CCl(4)-induced hepatic fibrosis, improved liver function, and downregulated the expression of fibrosis markers. Additionally, MCL significantly inhibited LX-2 cell activation by suppressing cell proliferation, extracellular matrix (ECM) production, and autophagy, while activating the MEK/ERK pathway. Moreover, MCL elevated intracellular and mitochondrial reactive oxygen species (ROS) levels, reduced mitochondrial membrane potential, and altered mitochondrial morphology. The ROS scavenger N-acetylcysteine (NAC) attenuated MCL-induced MEK/ERK pathway activation and increased collagen type I alpha 1 (COL1A1) and fibronectin (FN) expression. Further analysis confirmed that MCL directly interacts with TrxR1 and TrxR2, leading to the inhibition of their enzymatic activities and the induction of ROS generation. Ultimately, MCL attenuated the fibrotic process and autophagic flux in LX-2 cells. Conclusions: The findings of our study confirmed that MCL has the potential to alleviate hepatic fibrosis, thereby introducing a novel candidate drug and therapeutic strategy for management of this condition.