普罗布考抑制过氧化氢刺激大鼠主动脉平滑肌细胞增殖的机制

Antiproliferative Mechanisms of Probucol in H_2O_2-Stimulated Rat Aortic Smooth Muscle Cells

目的研究普罗布考抑制过氧化氢促大鼠主动脉平滑肌细胞增殖的机制。方法采用MTT3、H-胸腺嘧啶核苷掺入法、流式细胞术和逆转录聚合酶链反应观察过氧化氢刺激条件下普罗布考对血管平滑肌细胞细胞周期、DNA合成、细胞增殖和凋亡的影响。结果普罗布考抑制过氧化氢刺激血管平滑肌细胞增殖和DNA合成。与过氧化氢组比较,普罗布考+过氧化氢组细胞计数、吸光度值和3H-胸腺嘧啶核苷掺入量分别下降了46.9%、45.0%和39.5%(P<0.05)。普罗布考通过使血管平滑肌细胞生长停滞在G0/G1期抑制过氧化氢刺激细胞增殖。过氧化氢使细胞外信号调节激酶1 mRNA相对表达量增加近6倍,丝裂原活化蛋白激酶磷酯酶1 mRNA相对表达量下降了82.2%。普罗布考抑制细胞外信号调节蛋白激酶1 mRNA的表达,增强丝裂原活化蛋白激酶磷酯酶1 mRNA的表达。普罗布考诱导过氧化氢刺激条件下血管平滑肌细胞凋亡。结论普罗布考通过下调细胞外信号调节蛋白激酶1 mRNA的表达抑制细胞周期运转和诱导血管平滑肌细胞凋亡两种机制抑制过氧化氢刺激血管平滑肌细胞增殖。

Aim To investigate the antiproliferafive mechanisms of probucol in rat vascular smooth muscle cells （VSMC） stimulated by H2 O2. Methods Effects of probucol on cell cycle, DNA synthesis, coll proliferation and apoptesis in the presence of H2O2 were observed by means of M＇IT test, coll number count, ^3H-TdR incorporation, FCM and RT-PCR. Results Probucol significantly inhibited proliferation and DNA synthesis of VSMC stimulated by H2O2. Cell number, A value and 3H-TdR incorporation in probucol ＋ H2O2 group were reduced by 46.9%, 45.0%, and 39.5 %, respectively, compared with H2O2 group （ P 〈 0.05 ）. Probucol protected against H2O2 -induced VSMC proliferation through inducing cell growth arrest at G0/G1 phase. H2O2 increased extraceilular signal-regulated kinase-1 （ERK-1） mRNA transcriptional levels by about 6 times and decreased mitogen-activated protein kinases phesphatase-1 （MKP-1） n^xNA by 82.2%, respectively, compared with controls. Probucol down-regulated the increase in H2 O2-stimulated ERK-1 mRNA level and up-regulated MKP-1 mRNA level decreased by H2O2. Probucol induced apoptosis of VSMC under H2P2-stimulated condition. Conclusion Probucol suppresses H2O2-stimttlated VSMC proliferation by inhibition of coll cycle progression via down-regulating ERK-1 mRNA transcriptional level, as well as inducton of apoptosis of VSMC.