CD40L刺激诱导型环氧合酶表达及普伐他汀的作用

Effect of pravastatin on cyclooxygenase-2 expression induced by rhCD40L in cultured U937 cells

目的探讨重组人CD40配体(rhCD40L)对培养的人单核细胞(U937)表达诱导型环氧合酶(COX-2)的作用和普伐他汀对其影响。方法体外培养U937细胞,以0.05、0.1、0.2μg/m l的rhCD40L分别刺激24 h;0.4μg/m l的rhCD40L分别刺激3、6、12、24 h;终浓度10、1、0.1 mmol/L的普伐他汀与0.4μg/m l的rhCD40L共同刺激U937细胞24 h。RT-PCR检测COX-2 mRNA表达,W estern-b lot检测COX-2蛋白表达,ELISA法检测前列腺素E2(PGE2)的浓度反映COX-2酶活性。结果0.4μg/m l的rhCD40L刺激后3 h可诱导COX-2 mRNA和蛋白表达,随着rh-CD40L浓度和作用时间增加,COX-2 mRNA和蛋白表达显著增加(P<0.01),且呈时效和量效关系;同样,rhCD40L以时间和剂量依赖的方式增加U937细胞中PGE2的合成。0.4μg/m l的rhCD40L与普伐他汀共同刺激24 h后,COX-2的表达显著被抑制。结论rhCD40L以时间和浓度依赖的方式诱导COX-2的表达,普伐他汀可以抑制此作用。

AIM To evaluate cyclooxygenase-2 expression induced by rhCD40L in cultured U937 cells and possible inhabition inhibition by pravastatin. METHODS U937 cells were pretreated with rhCD40L of different concentrations and time intervals and COX-2 mRNA and protein expression were observed by RT-PCR and Western-blot respectively. For COX-2 enzyme activity, PGE2 released by U937 cells was measured by ELISA. RESULTS rhCD40L increased the expression of COX-2 in a time- and dose-dependent manner （ P 〈 0.01 ）. Pravastatin inhibited the expression of COX-2 induced by rhCD40L in a dose-dependent manner （P 〈0.01 ）. CONCLUSION rhCD40L can induce cyclooxygenase-2 expression in a dose and time dependent manner. Pravastatin inhibits this enhanced expression in U937 cells.