Functions Of Periostin In The Development Of MCD Diet-induced Nonalcoholic Steatohepatitis

Nonalcoholic Steatohepatitis (NASH) is one kind of steatohepatitis, which is caused by factors except for alcohol, virus and heredity. This disease is with symptoms of excess accumulation of lipid in hepatocytes, liver inflammation and fibrosis. It can progress to cirrhosis, even to hepatocellular carcinoma. Although there is lots of studys on the pathogenesis of nonalcoholic steatohepatitis, we still know little about its mechanisms. Periostin, which is an extracellular matrix protein, participates in many processes including development, tissue repair and tumorigenesis. Periostin is also closely related with various inflammatory diseases, such as asthma and pneumonia, but the relationship between Periostin and hepatitis remains unknown. So our research focuses on the role of periostin in the development of NASH, a special kind of hepatitis. We used a mouse model of NASH induced by MCD diet, and found the hepatic periostin expression were increased in MCD diet-fed mice compared to comtrlos. When the periostin-/-mice were fed MCD diet, these mice showed reduced steatosis, inflammation and fibrosis compared to wide-type mice. We also used a vitro model to study the effect of hepatic lipid accumulation on HSC, which proved that the conditioned media from steatotic human hepatocytes (QSG7701) could induce the human hepatic stellate cells (LX-2) to secret periostin. On the other hand, the overexpression of periostin could increase the PPARy expression of QSG7701after exposure to palmitate. Thus, our data demonstrate that periostin participates in the progression of NASH.