The effects of TGF-β1 and Smad2 on liver fibrosis of biliary atresia / 天津医药

ABSTRACT

Objective To investigate the expression and function of transforming growth factor (TGF)-β1 and Smad2 in liver fibrosis of biliary atresia (BA). Methods Liver biopsy specimens were collected from autopsy (normal group, n=5), congenital biliary dilatation (CBD group, n=10), BA patients underwent Kasai procedure (early hepatic fibrosis group, n=19) and liver transplantation (transplantation group, n=11). The first three groups were collected from January 2010 to July 2014 in Tianjin Children’s Hospital, and the last group was collected from January 2013 to January 2014 in Tianjin First Central Hospital. The hematoxylin and eosin (HE) stain were used to observe the degree of liver fibrosis of four groups. Immunohistochemistry (IHC) was used to observe expressions of TGF-β1 and Smad2 in liver tissues of these samples. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to test the quantitative mRNA of TGF-β1 and Smad2 in these samples. Results Results of HE showed that no fibrosis in autopsy group, mild fiber cell hyperplasia in CBD group, severe fibrosis in Kasai group and significant pseudolobule in transplantation group. Results of IHC showed that TGF-β1 was expressed in the cytoplasm of hepatocytes, bile duct cells, lymphocytes and neutrophils. The average optical density of TGF-β1 was the highest in Kasai group compared with that of other three groups (P 0.05). Results of qRT-PCR showed that both TGF-β1 mRNA and Smad2 mRNA were the highest in early hepatic fibrosis group than those of CBD group and transplantation group (P<0.017). Conclusion In early stage of BA, TGF-β1 and Smad2 promote liver fibrosis until the formation of P-P,P-C desmosome structure. However, with BA fibrosis becomes more serious, the pro-fibrogenic function of TGF-β1 and Smad2 becomes less.