OBJECTIVETo investigate the dynamic expression of TPM1 in rat model of hepatic fibrosis and hepatic stellate cells induced by TGFβ1.

METHODThirty male SD rats were divided into control group (n = 6) and model group (n = 24). The rat model of hepatic fibrosis was established by intraperitoneal injection of dimethylnitrosamine(DMN). The sera were collected from portal vein and liver tissues were taken from animals 2, 4, 6, 8 weeks HSC-T6 cells were cultured and induced 48 hours by 5 ng/ml TGF-β1. The pathological changes of liver were observed by Hematoxylin-Eosin and Masson Staining. Reverse Transcription-polymerase chain reaction (RT-PCR), immunohistochemistry and Western-blotting were used to determine the mRNA and protein expressions of TPM1, TGFβ1 and α-SMA in rat models and HSC-T6 cells and the localization of TPM1 in rat models.

RESULTSRat models of hepatic fibrosis were successfully established. TPM1 was lowly stained in the wall of blood vessels in portal areas in normal livers, in fibrotic livers TPM1 was mainly stained along the fibrotic septum. The mRNA and protein expressions of TPM1 and α-SMA in rat models of hepatic fibrosis increased at the week 2 and peaked at week 6, which was statistical significance compared to control group, P < 0.05; TGF-β1 increased at week 2 and it was higher than the levels in other groups at week 4, which was statistical significance compared to control group P < 0.05; Correlation analysis showed that TPM1 positively correlated with α-SMA and TGF-β1, rs = 0.688, rs = 0.692, P < 0.01. In HSC-T6, the mRNA expressions of TPM1 and α-SMA increased after being induced by TGF -beta1. compare with control group, the differences were significant, P less than 0.05.

CONCLUSIONTPM1 may be playing an important role in the occurrence and development of liver fibrosis. Maybe it could become a potential therapeutic target for hepatic fibrosis.