泛素-蛋白酶体抑制剂对大鼠肺成纤维细胞凋亡和增殖的影响

Effect of Proteasome Inhibitor on Apoptosis and Proliferation of Pulmonary Fibroblasts

目的:探讨泛素蛋白酶体抑制剂MG-132对大鼠肺成纤维细胞凋亡和增殖的影响,并初步探索其机制。方法:18只SD大鼠随机分成模型组(n=9)与对照组(n=9),模型组气管内一次性注入博莱霉素(5mg/kg),对照组气管内注入等量无菌生理盐水,分别于7,28,45d每组处死动物3只,提取成纤维细胞进行培养并用相同浓度的MG-132(1.0μmol/L)对成纤维细胞干预24h,应用MTT比色法检测细胞增殖情况,应用流式细胞仪检测细胞凋亡率,用免疫组化技术半定量观察成纤维细胞α-平滑肌动蛋白(α-SMA)和NF-κB的表达情况。①MG-132对模型组成纤维细胞的抑制和促凋亡的作用强于对照组成纤维细胞(P<0.05),其中,对7d模型组成纤维细胞的促凋亡作用最强;②MG-132干预后,模型组成纤维细胞α-SMA和NF-κB的表达逐渐减少,但仍高于对照组成纤维细胞(P<0.05)。结论:泛素蛋白酶体抑制剂MG-132对肺成纤维细胞有抑制和促凋亡作用,可能与减少肺成纤维细胞向肌成纤维细胞的转化及抑制NF-κB的表达有关。

Objective：To investigate the effect of proteasome inhibitor on apoptosis and proliferation of pulmonary fibroblasts in rats.Methods：Eighteen rats were randomly divided into model group（n=9） and control group（n=9）.Model group received Bleomycin（5 mg/kg） by intratracheal instillation and the control group was treated with the same volume of saline.Three rats respectively in model group and in control group were sacrificed on the 7th,28th and 45th days respectively after the intratracheal instillation,and pulmonary fibroblasts were also Abstracted respectively.The level of cell proliferation was detected by MTT and the rate of apoptosis was detected by flow cytometry.The immunohistochemical technique was adopted to observe the expression of α-smooth muscle actin（SMA） and NF-κB in pulmonary fibroblasts.Results：MG-132 could inhibit the proliferation and induce the apoptosis of pulmonary fibroblasts,but the effect on model group were stronger than that on control group（P0.05）.Model group on the 7th day had the highest apoptosis rates.After treatment with MG-132,the expression of α-SMA and NF-κB in pulmonary fibroblasts of model group were decreasing,but still higher than that in control group（P0.05）.Conclusion：MG-132 can inhibit the proliferation and induce the apoptosis of pulmonary fibroblasts.The mechanism may contribute to reducing transformation of myofibroblast and inhibiting expression of NF-κB.