TLR4 and Hepatic fibrosis: Moreover HSCs, regardless of etiology, are the prime contributors to liver fibrosis [145,146,147], and recent studies have shown that free cholesterol mediates the activation of HSCs by upregulating TLR4 protein and thereby rendering them susceptible to TGF-β induced activation in a vicious cycle of liver fibrosis [117,118,119,120,121].