San‐Huang‐Xie‐Xin‐Tang extract suppresses hepatitis C virus replication and virus‐induced cyclooxygenase‐2 expression

Lee, J.‐C.; Tseng, C.‐k.; Wu, S.‐F.; Chang, F.‐R.; Chiu, C.‐C.; Wu, Y.‐C.

Summary. Chronic hepatitis C virus (HCV) infection is associated with chronic inflammation of liver, which leads to the development of cirrhosis and hepatocellular carcinoma (HCC). Because of severe side effects and only a 50–70% cure rate in genotype 1 HCV‐infected patients upon current standard treatment with pegylated interferon‐α plus ribavirin, new therapeutic regimens are still needed. San‐Huang‐Xie‐Xin‐Tang (SHXT) is a transitional Chinese herbal formula, composed of Rhei rhizoma, Scutellaria radix and Coptidis rhizome, and possesses anti‐inflammatory effect. Here, we describe a (+)‐catechin‐containing fraction extracted from SHXT, referred as SHXT‐frC, exhibited effective inhibition of HCV replication, with selectivity index value (SI; CC(50)/EC(50)) of 84, and displayed synergistic anti‐HCV effects when combined with interferon‐α, HCV protease inhibitor telaprevir or polymerase inhibitor 2′‐C‐methylcytidine. The activation of factor‐κB (NF‐κB) and cyclooxygenase‐2 (COX‐2) signalling pathway has particular relevance to HCV‐associated HCC. SHXT‐frC treatment also caused a concentration‐dependent decrease in the induction of COX‐2 and NF‐κB expression caused by either HCV replication or HCV NS5A protein. Collectively, SHXT‐frC could be an adjuvant treatment for patients with HCV‐induced liver diseases.