雷公藤甲素对哮喘豚鼠嗜酸粒细胞凋亡及Fas,Bcl-2 mRNA表达的影响

目的 :观察雷公藤甲素 (triptolide ,TP)对体外不同密度嗜酸粒细胞 (eosinophils ,Eos)凋亡及Fas ,Bcl 2mRNA表达的影响 ,探讨其促进哮喘时Eos凋亡的机制。方法 :卵蛋白激发豚鼠哮喘 4 8h后行支气管肺泡灌洗 ,分离不同密度Eos。加入TP10 - 7～ 10 - 4mol·L- 1,以原位杂交检测Eos的Fas及Bcl 2mRNA表达 ,TUNEL法检测细胞凋亡。结果 :TP干预 2 4h ,可见细胞凋亡增加 ,FasmRNA表达增加 ,Bcl 2mRNA表达降低 ,呈剂量依赖性。Fas表达与Eos凋亡呈正相关 ,而Bcl 2的表达与Eos凋亡呈负相关。结论 :TP可促进Fas表达 ,抑制Bcl 2表达 ,促进Eos凋亡。Fas表达增加及Bcl 2表达减少是TP调节Eos凋亡的机制之一

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.