As shown in Supporting Fig. 2A, the percentage of GFPlow cells (minimal collagen promoter activity) in UV+ (vitamin

A containing) HSCs is reduced from 9.5% to 2.1%, whereas the percentage of GFPhigh/UV+ HSCs increases in BDL mice as compared to sham-operated animals, indicating activation of HSCs in the model. Further, qPCR analysis of all UV+ HSCs from BDL versus sham mice reveals induction of HSC activation markers such as α1(I)procollagen (Col1a1), Sma, and Timp1 in BDL HSCs but not Desmin (Supporting Fig. 2B). Having confirmed that http://www.selleckchem.com/products/MDV3100.html HSCs are indeed activated in the model, we tested the effects of daily intraperitoneal administration of RA versus vehicle during the second week of BDL. The liver to body weight percentage was not different between RA or vehicle-treated mice (6.8 ± 0.7 versus 6.3 ± 0.3), nor were the plasma alanine aminotransferase (ALT) levels (157 ± 71 versus 283 ± 95, P = 0.29). However, the digital morphometric analysis of Sirius red-stained collagen fibers shows a significant attenuation of liver fibrosis by RA treatment (Fig. 5I). To examine whether this antifibrotic effect of RA is associated with suppressed activation of HSCs in vivo, immunohistochemistry for SMA and desmin were performed (Supporting

Fig. 2C). In the sham-operated liver, expression of SMA is primarily seen in the hepatic artery and a very few cells around the bile duct, but not in HSCs in the sinusoid (Supporting Fig. Bay 11-7085 2C, upper and lower left panel). In the vehicle-treated selleck chemicals llc BDL liver, expression of SMA increases in desmin+ portal MFs and HSCs (Supporting Fig. 2C, upper and lower middle panel). RA treatment reduces the percentage of SMA+ MFs by 40% and that of SMA+ HSCs by 75% (Supporting Fig. 2C,D). The density of desmin+ HSCs increases

by BDL, but RA treatment has no effect on this change (Supporting Fig. 2D). No TUNEL+ HSCs or hepatocytes are detected in the liver parenchyma of either RA- or vehicle-treated BDL livers. These data indicate that RA suppresses activation of both portal MFs and HSCs in BDL-induced liver injury. Hepatic mRNA levels of α1(I)procollagen and SMA are also significantly reduced by RA treatment (Fig. 5J), further supporting antifibrotic effects of RA in this model. Taken together, these data indicate that RA suppresses activation of HSCs and liver fibrosis in BDL-induced liver injury. The present study demonstrates that the MeCP2-EZH2 relay of Pparγ epigenetic repression is an important target for the antifibrotic effect of the herbal prescription YGW. Polyphenolic RA and flavonoid BC are identified as active phytochemicals in YGW that reverse epigenetic Pparγ repression and activated phenotype of HSCs.