Vitamin E pretreated Wharton's jelly-derived mesenchymal stem cells attenuate CCl4-induced hepatocyte injury in vitro and liver fibrosis in vivo.

Oxidative microenvironment in fibrotic liver alleviates the efficacious outcome of mesenchymal stem cells (MSCs)-based cell therapy. Recent evidence suggests that pharmacological pretreatment is a rational approach to harness the MSCs with higher therapeutic potential. Here, we investigated whether Vitamin E pretreatment can boost the antifibrotic effects of Wharton's jelly-derived MSCs (WJMSCs). We used rat liver-derived hepatocytes injured by CCl4 treatment in co-culture system with Vitamin E pretreated-WJMSCs (Vit E-WJMSCs) to evaluate the hepatoprotective effect of Vit E-WJMSCs. After 24 h of co-culturing, we found that Vit E-WJMSCs rescued injured hepatocytes as hepatocyte injury-associated medium (AST, ALT, and ALP) and mRNA (Cyp2e1, Hif1-α, and Il-1β) markers reduced to normal levels. Subsequently, CCl4-induced liver fibrosis rat models were employed to examine the antifibrotic potential of Vit E-WJMSCs. After 1 month of cell transplantation, it was revealed that Vit E-WJMSCs transplantation ceased fibrotic progression, as evident by improved hepatic architecture and functions, more significantly in comparison to naïve WJMSCs. In addition, Vit E-WJMSCs transplantation decreased the expressions of fibrosis-associated gene (Tgf-β1, α-Sma, and Col1α1) markers in the liver parenchyma. Intriguingly, the results of tracing experiments discovered that more WJMSCs engrafted in the Vit E-WJMSCs treated rat livers compared to naïve WJMSCs treated livers. These findings implicate that pretreatment of WJMSCs with Vitamin E improves their tolerance to hostile niche of fibrotic liver; thereby further enhancing their efficacy for hepatic fibrosis.