Effects of triptolide on expression of Fas and Bcl-2 mRNA and apoptosis in eosinophils in asthmatic guinea-pigs

AIM: To investigate the effects of triptolide (TP) on expression of Fas and Bcl-2 mRNA and apoptosis in eosinophils (Eos) in vitro, and mechanism of TP promoting Eos apoptosis. METHODS: The giunea pigs were stimulated by ovalbumin (Ova) for 48 h the bronchalveolar lavage was operated, hypodense Eos(HEos) and Normodense Eos (NEos) were purified from BALF by gradients of percoll. Eos cultured in PRMI 1640 medium. After adding TP 10 -7～10 -4 mol·L -1 in the wells, the mRNA of Fas and Bcl-2 in Eos was measured by hybridization. Apoptosis was detected by TdT-mediated dUTP nick end labeling. RESULTS: Eos cultured under the condition of TP administration in vitro for 24 h, apoptotic Eos increased, Fas mRNA expression increased and the Bcl-2 mRNA expression decreased in a dose-dependent manner. There was positive correlation between Eos apoptosis and Fas mRNA expression. The expression of Bcl-2 mRNA was inversely correlated with Eos apoptosis. CONCLUSION:TP promotes Eos apoptosis, increase expression of Fas and inhibit expression of Bcl-2 in dose-dependent manner in vitro. The increasing of expression of Fas and decreasing of expression of Bcl-2 may be one of mechanism of TP's promoting apoptosis of Eos.