CCL2 and gallstones: Both MCP-1 and IL-1β contribute to MCD diet-induced non-alcoholic steatohepatitis.203 Asai et al. showed that cholesterol induces HIF-1α activation and liver steatosis, and HIF-1α reduces the expression of hepatic aquaporin 8 (AQP8) and promotes cholesterol gallstone formation.204 The high expression of hepatic HIF-1α is observed in the livers of patients with NAFLD and gallstones than in those without gallstones.204