Arctigenin Attenuates Hepatic Stellate Cell Activation via Endoplasmic Reticulum-Associated Degradation (ERAD)-Mediated Restoration of Lipid Homeostasis.

Arctigenin, a natural lignan from Arctium lappa L., exhibits potent antifibrotic activity, yet its molecular mechanisms remain unclear. Endoplasmic reticulum (ER) stress is known to promote hepatic stellate cell (HSC) activation and liver fibrosis. This study investigates the therapeutic potential of arctigenin in HSC activation through ER stress modulation. Primary rat HSCs were activated (3-7 days) and treated with tunicamycin (ER stress inducer) or 4-PBA (ER stress inhibitor). Arctigenin attenuated ER stress markers (e.g., GRP78) and suppressed the expression of fibrotic marker α-SMA in ER stress-challenged activating (day 3) and activated (day 7) HSCs. Arctigenin restored lipid homeostasis by modulation of both lipogenesis (via Dgat2 and Ppar-γ upregulation) and lipolysis (suppression via ATGL inhibition). ER stress activated ER-associated degradation (ERAD), triggering the formation of small lipid droplets (LD). Arctigenin normalized the ERAD activity, thereby rescuing LD integrity and suppressing HSC activation. Our findings demonstrate that arctigenin mitigates HSC activation by suppressing ER stress and restoring lipid homeostasis via modulating ERAD-mediated lipid dysregulation. As a dietary and medicinal compound, arctigenin emerges as a promising therapeutic candidate for liver fibrosis.