Macrophages evoke autophagy of hepatic stellate cells to promote liver fibrosis in NAFLD mice via the PGE2/EP4 pathway.

The pathogenesis of liver fibrosis in nonalcoholic fatty liver disease (NAFLD) remains unclear and the effective treatments have not been explored yet. The activation of hepatic stellate cells (HSCs) is considered as the most critical factor in the progression of liver fibrosis and cirrhosis. Autophagy has recently been identified as a new mechanism to regulate HSC activation.