降钙素基因相关肽对人支气管上皮细胞分泌MMP-9的影响

目的:探讨降钙素基因相关肽(calcitonin-gene-related peptide,CGRP)对人支气管上皮细胞分泌基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)/明胶酶B的影响及其机制.方法:采用逆转录聚合酶链式反应及明胶酶谱法,观察给予不同浓度的CGRP(10-10～10-6 mol/L)刺激及CGRP 10-6mol/L刺激后不同时间点(6,12,18,24,36和48 h)MMP-9活性和基因表达量的变化.结果:体外培养的人支气管上皮细胞能分泌MMP-9;CGRP干预呈剂量及时间依赖方式上调人支气管上皮细胞MMP-9的活性和MMP-9 mRNA的表达(P＜0.01);CGRP上调人支气管上皮细胞MMP-9活性和表达的作用可为蛋白激酶C阻断剂H-7及钙调蛋白阻断剂W-7部分逆转(P＜0.05).结论:CGRP可明显上调人支气管上皮细胞MMP-9的活性和表达,其胞内信号转导机制与蛋白激酶和钙调蛋白信号途径有关.

Effect of calcitonin-gene-related peptide on MMP-9production in human bronchial epithelial cells

Objective To examine the expression of matrix metalloproteinase-9 (MMP-9) in human bronchial epithelial cells treated with calcitonin-gene-related peptide (CGRP). Methods RT-PCR and gelatin zymography were performed to examine the dynamic expression and activity of MMP-9 in human bronchial epithelial cells at different doses (10-10, 10-9, 10-8, 10-7, and 10-6 mol/L) and different time points (6,12,18,24,36, and 48 h) after the stimulation of CGRP. Results The unstimulated human bronchial epithelial cells only secreted a small amount of MMP-9. After the CGRP stimulation, the expression of MMP-9 presented in a concentration-dependent (10-10, 10-9, 10-8, 10-7, and 10-6 mol/L) and time-dependent (6,12,18,24,36, and 48 h) manners (P<0.01) in human bronchial epithelial cells. The effect of CGRP could be diminished by H-7 and W-7, an antagonist of protein kinase C (PKC) and calmodulin (CaM) (P<0.05). Conclusion CGRP can stimulate the secretion and expression of MMP-9 in human bronchial epithelial cells, and the signal transduction is partly via the PKC and CaM pathway.