[Impact of artesunate on the expression and secretion of transforming growth factor-b1 of primary rat hepatic stellate cells].

Objective: To investigate the impact of the Artemisia annua plant-derived drug, artesunate, on proliferation of primary rat hepatic stellate cells (HSCs), and to analyze the underlying molecular mechanisms of its anti-fibrogenic effects involving the inhibition of transforming growth factor-beta 1 (TGF-b1) expression and secretion in liver.

Method: Isolated, cultured, and activated primary rat HSCs were divided into sixteen groups, including one untreated control group and fifteen artesunate-treated experimental groups with 125, 150, 175, 200 or 225 mumol/L for 24, 48 or 72 hours. The rate of cellular proliferation was measured using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. TGF-b1 mRNA expression was evaluated by reverse transcription-polymerase chain reaction and protein expression was evaluated by Western blotting. Enzyme-linked immunosorbent assay was used to evaluate secreted levels of TGF-b1 protein.

Results: Artesunate significantly inhibited proliferation of cultured HSCs in a dose- and time-dependent manner (all, P less than 0.01). After 24 hours of exposure, the inhibition ratios of the various artesunate concentrations were: 6.06%+/-1.44% (125 mumol/L), 21.47%+/-5.57% (150 mumol/L), 42.00%+/-7.36% (175 mumol/L), 67.12%+/-4.55% (200 mumol/L), and 79.83%+/-3.67% (225 mumol/L). Artesunate significantly inhibited the TGF-b1 mRNA expression in HSCs, and the higher the drug concentration, the higher the degree of inhibition (all, P less than 0.01). In addition, artesunate significantly inhibited the expression of intracellular and secreted TGF-b1 protein (all, P less than 0.01). In response to artesunate (mumol/L concentrations), the TGF-b1 levels were (164.24+/-6.88) pg/ml (0μmol/L), (102.68+/-4.45) pg/ml (150μmol/L), (86.54+/-5.56) pg/ml (175μmol/L), and (56.55+/-5.66) pg/ml (200μmol/L).

Conclusion: Artesunate exerts anti-fibrogenic effects on HSCs in vitro, possibly by reducing the expression, translation and secretion of TGF-b1.