5-氮杂-2’-脱氧胞苷对软骨细胞中炎性介质和一氧化氮合酶表达的影响

Effects of 5-Aza-CdR on interleukin-1β, transforming growth factor -β and nitric oxide synthase expression in human chondrocyte

目的探讨甲基化抑制剂5氮杂-2＇-脱氧胞苷（5-Aza—CdR）对软骨细胞白介素18（IL-1β）、转化生长因子β（TGF-β）和一氧化氮合酶（NOS）基因表达的影响。方法收集骨关节炎患者（OA组，22例）、类风湿关节炎患者（RA组，3例）及外伤患者（对照组，10例）软骨标本并进行细胞培养，检测软骨细胞中IL-1β、TGF-β和NOSmRNA表达水平；用甲基化抑制剂5Aza—CdR（浓度为10μmol／L）培养对照组正常软骨细胞72h，检测软骨细胞IL-1β、TGF-β和NOSmRNA及蛋白表达水平。结果软骨细胞中IL-1β、TGF—β和NOSmRNA表达水平，OA组及RA组明显高于对照组（P〈0．05），但在OA组及RA组之间表达差异无统计学意义；对照组正常软骨细胞加入5-Aza—CdR培养72h后，IL-1β、TGF-β和NOS的mRNA表达水平明显升高（P〈0．05），且IL-1β、TGF-β和NOS蛋白水平也显著升高（P〈0．05）。结论在OA患者和RA患者软骨细胞中IL-1β、TGF—β和NOSmRNA表达均明显升高，而5-Aza-CdR可以诱导IL-1β、TGF-β和NOS甲基化状态改变调节IL-1β、TGF0和NOSmRNA及蛋白表达升高，推测低甲基化可能参与了炎症信号通路及细胞凋亡，从而多层次的参与了OA的发生发展。

Objective To investigate the effects of 5-Aza-CdR （methyiation transterase inhibitor） on gene expression levels of interleukin-1β（IL-1β）, transforming growth factorβ （TGF-β） and nitric oxide synthase （NOS） in chondrocytes. Methods Chondrocytes from patients with osteoarthritis （OA） （n= 22）, rheumatoid arthritis （RA） （n= 3） or trauma without rheumatic diseases （n=10） were collected and cultured. The mRNA expression levels of IL-1β, TGF-β and NOS were detected by real-time polymerase chain reaction （RT-PCR）. Chondrocytes in trauma group were treated with 5 Aza-CdR（10 μmol/L） for 72 h, and the mRNA and protein expression levels of IL-1β, TGF-β and NOS were detected by RT-PCR and ELISA, respectively. Results The mRNA expression levels of IL-1β, TGF β and NOS were increased in OA and RA group as compared with trauma group （P〈0.05）, while they had no differences between OA and RA groups. After treated with 5 Aza-CdR, the mRNA and protein expression levels of IL-1β, TGF-β and NOS in chondroeytes rised in trauma group as compared with pretreatment （all P〈 0.05）. Conclusions The mRNA expression levels of IL-1β,TGF-β and NOS in ehondroytes are higher in OA and RA patients. 5-Aza- CdR could increase the mRNA and protein expression levels of IL-1β, TGFβ and NOS by inducing relative gene methylation, which suggests demethylation might play a role in OA pathogenesis by influneing the inflammatory signal pathway or cell apoptosis.