活性氧对平滑肌细胞合成基质金属蛋白酶-1, 3及其抑制物的影响

目的:探讨活性氧(ROS)对血管平滑肌细胞合成基质金属蛋白酶-1,3(MMP-1,3)和基质金属蛋白酶抑制物-1(TIMP-1)的影响,从而推测其是否促进动脉粥样硬化斑块的破裂。方法:体外培养胎儿主动脉平滑肌细胞,加入含100μmol/L黄嘌呤,5U/L黄嘌呤氧化酶的无血清培养液,孵育24h,收集细胞上清液。用Westernblotting方法检测浓缩后的细胞上清液中MMP-1,3和TIMP-1的含量。结果:黄嘌呤/黄嘌呤氧化酶组细胞上清液中的MMP-1含量明显少于正常对照组,并且转化成活性形式;MMP-3的含量明显多于正常对照组,并且转化成活性形式;TIMP-1的含量明显少于正常对照组。结论:ROS对MMPs-TIMPs平衡的影响很复杂,可能对动脉粥样硬化斑块的破裂起一定作用。

Regulation by reactive oxygen species of matrix metalloproteinase-1, 3 and tissue inhibitor of matrix metalloproteinase-1 in smooth muscle cells

AIM: To understand whether reactive oxygen species promote the rupture of atherosclerotic plaques by regulating the balance of matrix metalloproteinase-1, 3 (MMP-1, 3) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in smooth muscle cells. METHODS: Aortic smooth muscle cells from 4-6months-healthy abortive fetuses were incubated for 24 hours with xanthine (100 μmol/L) and xanthine oxidase (5 U/L) in vitro . MMP-1, 3 and TIMP-1 in the concentrated culture media were measured by Western blotting ( n =3 independent experiments). RESULTS: Incubation with xanthine/xanthine oxdiase decreased the amount of MMP-1 in the aortic smooth muscle cells (21.2%±5.5% of the control group), and pro-MMP-1 was activated completely. Reactive oxygen species (ROS) also activated pro-MMP-3, and increased the production of MMP-3 in the aortic smooth muscle cells. On the other hand, ROS inhibited the production of TIMP-1 in the aortic smooth muscle cells. CONCLUSION: It is complicated that ROS regulates the balance of MMPs and TIMPs. ROS may contribute to matrix degradation and the rupture in the atherosclerotic plaques.