青藤碱抗炎机理——青藤碱对人外周血单个核细胞环氧化酶活性及其基因表达的影响

The Effect of Sinomenine on Cyclooxygenase Activity and the Expression of COX-1 and COX-2 mRNA in Human Peripheral Monocytes

目的 :研究青藤碱对人环氧化酶 (COX)活性及其基因表达的影响 ,深入探讨青藤碱的抗炎药理机制。方法 :应用细胞培养 ,放射免疫测定 ,RT PCR等方法 ,观察青藤碱等药物对LPS刺激和非LPS刺激的体外培养的人外周血单个核细胞 (PBMC)产生前列腺素E2 CPGE2 C的影响 ,并深入研究其对COX 1和COX 2基因表达的作用。结果 :青藤碱对LPS刺激状态下正常人外周血单个核细胞PGE2 合成的抑制作用明显高于不加LPS的状态 ,间接反映青藤碱对COX 2的抑制作用较强。RT PCR结果表明青藤碱对人COX 1及COX 2的基因表达无明显影响。结论 :青藤碱对COX 2活性具有一定的选择性抑制作用 ,并可能主要是通过对COX酶活性的直接作用来实现。

Objective: To observe in vitro the effect of Sinomenine, a pure alkaloid extracted from the chinese medical plant Sinomenium acutum on the activity of cyclooxygenase(COX 1 and COX 2) and the expression of COX 1 and COX 2 mRNA. Method: Mononuclear leukocytes were obtained from healthy adults. Isolated mononuclear leucocytes from human peripheral blood(PBMC) were incubated (1×10 6·mL -1 ) with or without sinomenine (or indomethacin), after incubated for 24 hours at 37 ℃ with 5% CO 2 ; the media were assayed for the PGE 2 by radioimmunoassay(RIA). LPS was used to stimulate the monocytes at a concentration of 5 μg·mL -1 . And by RT PCR, both COX 1 and COX 2 mRNAs were detected in Mononuclear leukocytes after incubation for different hours with drug (sinomenine or indomethacin) or not.Result: LPS(stimulated) induced the production of PGE 2 in PBMC increasing with high expression of COX 2 mRNA; sinomenine reduced PGE 2 production in LPS stimulated human monocytes more than in non stimulated human monocytes. In comparative experiments, indomethacin, a non selective COX inhibitor, reduced the production of PGE 2 equally in both states. Meanwhile, neither sinomenine(0.1～1 mmol·L -1 ) nor indomethacin(0.5～10 μmol·L -1 ) inhibited the expression of both COX 1 and COX 2 mRNAs by RT PCR with β actin as reference.Conclusion: In contrast with indomethacin, Sinomenine shows a preferential inhibitory effect on COX 2 over COX 1, These results suggest that Sinomenine is a selective COX 2 inhibitor, which may be directly related to suppressing cyclooxygenase activity.[