内皮细胞与单核细胞相互作用对基质金属蛋白酶2和其组织抑制剂2分泌和活化的影响以及普伐他丁的作用

Effects of interaction between vascular endothelial cells and monocytes on expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinases 2 and regulation of pravastatin

目的 探讨内皮细胞和单核细胞相互作用对基质金属蛋白酶2(MMP -2)和其组织抑制剂(TIMP- 2)分泌及活化的影响以及普伐他丁在上述过程中的作用。方法 建立以不同比例混合的内皮细胞和单核细胞体外共同培养体系,培养24h后取上清采用明胶酶谱法检测MMP -2活性及逆明胶酶谱法检测TIMP- 2的活性。按1∶1比例混合培养的内皮细胞和单核细胞中,加入不同浓度的普伐他丁(0、0 .1、0. 5、1 0μmol/ml)作用24h后,用同样的方法测定MMP 2和TIMP- 2的活性。结果共同培养体系的细胞与内皮细胞单独培养相比较,MMP -2酶原(proMMP- 2)活性分别增高2 .09、2. 46和2 .07倍(n=8,P<0. 01),共同培养的细胞还能够分泌MMP -2的活性形式,其中以1∶1比例共同培养的细胞分泌的proMMP -2和活化MMP- 2增加最为显著。普伐他丁对proMMP -2及活化状态MMP 2的产生均有抑制(P<0 01),并呈剂量依赖效应,浓度在1 0μmol/ml以上的普伐他丁可完全抑制活化MMP-2的分泌。逆明胶酶谱法检测结果显示,混合培养的细胞TIMP- 2活性较两种细胞单独培养均有一定程度的降低(P<0 .05),但与细胞混合的比例无关。普伐他丁对TIMP -2活性无明显影响。结论 内皮细胞与单核细胞相互作用能够促进MMP- 2的分泌和活化,并能抑制TIMP- 2的分泌,而且普伐他丁对MMP

Objective To analyze the effects of interaction between vascular endothelial cells and monocytes on the expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase 2 (TIMP-2), as well as the regulation of pravastatin. Methods A co-cultured system of monocytes and endothelial cells was established through addition of THP-1 to human umbilical vein endothelial cells (HUVECs) in various rates. After 24 hours, the changes in activity and expression of MMP-2 and TIMP-2 in the co-culture system were studied by zymography and reverse zymography. The 1∶1 co-culture system was selected and one control group (no pravastatin added) and experimental groups (with concentration of pravastatin being 0.1, 0.5 and 1.0 μmol/ml respectively) were studied. All groups were cultured for another 24 hours and analyzed in the same way. Results Compared to the single cultured HUVECs, the activity of proMMP-2 in the co-cultured system increased by 2.09, 2.46 and 2.07 folds respectively (number = 8, P<0.01). There was also activated MMP-2 secretion in the co-culture system. The secretion of proMMP-2 and active MMP-2 in the 1∶1 co-cultured system was most obvious. After pravastatin treatment, the activity of proMMP-2 and MMP-2, decreased significantly (number = 8, P<0.01). MMP-2 secretion was completely suppressed after 1.0 μmol/ml pravastatin treatment. Reverse zymography revealed that, compared to the single culture HUVECs or THP-1, the secretion of TIMP-2 decreased in the co-cultured system, regardless of the ratio of mixture. However, pravastatin had no obvious effect on TIMP-2. Conclusions Interaction between vascular endothelial cells and monocytes may contribute to the secretion and activation of MMP-2 and suppress secretion of TIMP-2. Pravastatin may inhibit the secretion and activation of MMP-2.