TLR4 and Hepatic fibrosis: The previous study demonstrated that the consumption of a high-cholesterol diet leads to the accumulation of free cholesterol in HSCs, which suppresses the expression of TGF-β photoreceptor BMP and Bambi, by increasing the TLR4 signaling pathway (11, 34), eventually, the TGF-β signaling pathway increases in HSCs, which activates HSCs and promotes liver fibrosis (11, 35).