桂皮醇对IL-1刺激脑微血管内皮细胞COX活性及PGE2释放的影响

 目的观察桂枝汤中分离获得的单体成分桂皮醇对发热相关的环氧酶(COX)和前列腺素E₂(PGE₂)的影响。方法建立大鼠脑微血管内皮细胞(rCMEC)培养,进行Ⅷ因子相关抗原鉴定。待细胞生长至融合状态后加入不同终浓度的桂皮醇(0.093,0.186,0.372,0.744,1.488 mmol·L^-1)孵育3 h,之后以30μg·L^-1的IL-1刺激12 h。ELISA方法检测细胞培养液中PGE2的含量及细胞内COX-1,COX-2的活性。结果Ⅷ因子抗体免疫组化染色可见95%的培养细胞呈阳性,确认为rCMEC。暴露于质量浓度为30μg·L^-1IL-1后,rCMEC内COX-2活性及释放的PGE2量显著增加(P<0.01),COX-1活性变化无统计学差异(P>0.05)。加入不同浓度的桂皮醇后,随浓度增加可下调COX-1、COX-2活性及PGE2量,且呈浓度依赖关系;至浓度为0.744mmol·L^-1时,COX-2活性及释放的PGE2与IL-1单独作用组相比均有显著性差异(P<0.05),COX-1活性虽有所降低,但无统计学上的显著差异(P>0.05)。结论桂皮醇能下调IL-1刺激rCMEC释放升高的PGE₂,作用机制可能与抑制COX-2活性有关。

Effect of Cinnamyl Alcohol on Activity of COX and PGE2 Release in Cerebral Microvascular Endothelial Cells Stimulated by IL-1

OBJECTIVE To observe the effect of cinnamyl alcohol on the activity of COX and PGE_2 release in rat cerebral microvascular endothelial cells(rCMEC) stimulated by IL-1.METHODS rCMEC were cultured,and identified by immunohistochemistry for Von Willebrand Factor(Ⅷ factor,a marker for all endothelial cells) in the cytoplasm of the cells.Different concentrations of cinnamyl alcohol were added respectively and incubated for 3 h,then IL-1 stimulated for another 12 h.The activity of COX-1 and COX-2 in rCMEC,and production of PGE₂ in the conditioned media were measured by ELISA.RESULTS Positive immunostaining for Ⅷ factor was present diffusely in the cytoplasm of >95% rCMEC.After being exposed to 30 μg·L^-1 IL,the activity of COX-2 in rCMEC and the production of PGE₂ in conditioned media were higher than those in control group(P<0.01),while there was no difference on the activity of COX-1 between the two groups((P>0.05)).Cinnamyl alcohol down-regulated them with a concentration-dependen manner,and significant differences on the activity of COX-2 and amount of PGE₂ were showed as the concentration reached 0.744 mmol·L^-1(P<0.05).CONCLUSION Cinnamyl alcohol can affect the PGE₂ release in rCMEC induced by IL-1,which might be related with its inhibition on the activity of COX-2.