Curcumin: potential for hepatic fibrosis therapy?

The beneficial antioxidative, anti-inflammatory and antitumorigenic effects of curcumin have been well documented in relation to cancer and other chronic diseases. Recent evidence suggests that it may be of therapeutic interest in chronic liver disease. Hepatic fibrosis (scarring) occurs in advanced liver disease, where normal hepatic tissue is replaced with collagen-rich extracellular matrix and, if left untreated, results in cirrhosis. Curcumin inhibits liver cirrhosis in a rodent model and exerts multiple biological effects in hepatic stellate cells (HSCs), which play a central role in the pathogenesis of hepatic fibrosis. In response to liver injury, these cells proliferate producing pro-inflammatory mediators and extracellular matrix. Curcumin induces apoptosis and suppresses proliferation in HSCs. In addition, it inhibits extracellular matrix formation by enhancing HSC matrix metalloproteinase expression via PPAR gamma and suppressing connective tissue growth factor (CTGF) expression. In this issue, Chen and co-workers propose that curcumin suppresses CTGF expression in HSC by inhibiting ERK and NF-kappa B activation. These studies suggest that curcumin modulates several intracellular signalling pathways in HSC and may be of future interest in hepatic fibrosis therapy.