Serum from hepatectomized rats induces the differentiation of adipose tissue mesenchymal stem cells into hepatocyte-like cells and upregulates the expression of hepatocyte growth factor and interleukin-6 in vitro

: Adipose tissue-derived mesenchymal stem cells (AT-MSCs) are an attractive alternative for clinical application due to their minimally invasive accessibility and availability in the body. However, the hepatic differentiation efficiency of AT-MSCs is insufficient for therapeutic application and the role of extrahepatic stem cells in liver regeneration remains poorly understood. This study was designed to investigate the effects of serum from rats subjected to 70% partial hepatectomy (PH) on the differentiation ability of rat AT-MSCs in vitro, and to explore the potential role of AT-MSCs in vivo following PH injury. Results showed that AT-MSCs treated with serum collected from rats 24 h after 70% PH differen-tiated into hepatocyte-like cells, resembled hepatocyte-like cells with round or polygonal shape, expressed α-fetoprotein, secreted albumin, synthesized urea and acquired cytochrome P450 type 3A4 enzyme activity, and upregulated the expression of interleukin (IL)-6 and hepatocyte growth factor (HGF) transiently in vitro, although the hepatic differentiation efficiency was extremely low. AT-MSC transplantation after 70% PH ameliorated liver injury and promoted liver regeneration, but did not increase the serum levels of IL-6 and HGF in vivo. This result suggests that the therapeutic effect of AT-MSCs in vivo after 24 h of 70% PH does not increase IL-6 and HGF expression.