Effect of Mast Cell Chymase on Activation, Proliferation and Transdifferentiation of Hepatic Stellate Cells.

BACKGROUND/AIMS: This work aims to observe the effects of mast cell (MC) chymase on activation, proliferation and transdifferentiation of hepatic stellate cells (HSCs) and to discuss the role of chymase in development of liver fibrosis.

METHODOLOGY: Rat HSCs were isolated by in situ perfusion using collagenase IV and proteinase E and density gradient centrifugation (Percoll method), followed by culture. After intervention by chymase with series of concentration (1, 10 and 100 ng/mL), MTT assay was performed to determine HSC proliferation. Expressions of α-SMA and TGF-β1 protein in HSCs were determined by Western blotting method, and TGF-β1 and Col-I mRNA expression were determined using semi-quantitive RT-PCR method.

RESULTS: MC Chymase could significantly promote the proliferation of HSCs (P < 0.05), with chymase concentration dependence from 1 ng/mL to 100 ng/mL. The OD value of HSCs in 100 ng/ml chymase group was 1.45 times to control group. Compared with control group, expressions of α-SMA and TGF-β1 protein and expressions of TGF-β1 and Col-I mRNA in chymase groups were significantly increased, respectively (P < 0.05), with chymase concentration dependence.

CONCLUSIONS: MC chymase can promote the activation, proliferation and transdifferentiation of HSCs, and plays an important role in occurrence and development of liver fibrosis.