Objective: To observe the repairing effect of adipose mesenchymal stem cells (ADSCs) on lung injury induced by silica in rats. Methods: Primary ADSCs-GFP was obtained from rats. ADSCs-GFP was injected into tail vein of silicosis model rats. The expression of green fluorescence in lungs was observed regularly to determine the homing ability of ADSCs. Primary ADSCs of rats were obtained and randomly divided into control group, exposure group, vehicle group and ADSCs group. Silicosis rat model was established by non-exposed tracheal drip method. 24 hours after silica exposure, rats in ADSCs group were injected with ADSCs of 1×10(6)/kg body weight through tail vein, and the pathological changes of lung tissue were observed and evaluated 28 days after intervention. To explore the early intervention mechanism of ADSCs on pulmonary fibrosis in silicosis model rats, apoptosis-related proteins were detected by immunohistochemistry. Results: 28 days after exposure to silica, rats in the exposure group showed obvious pulmonary fibrosis. Compared with exposure group and vehicle group, ADSCs group showed less pulmonary inflammation, less silica nodules and less collagen deposition area. Immunohistochemical results showed that the expression of Caspase-3 and cytochrome C protein decreased and Bcl-2 protein increased after ADSCs transplantation. Conclusion: ADSCs infusion has an obvious intervention effect on postponing early silicosis fibrosis in rats exposed to silica, and its mechanism is related to the regulation of apoptotic process.
目的： 观察脂肪间充质干细胞（ADSCs）对矽尘所致大鼠肺损伤的修复作用。 方法： 选取SPF级健康雌性SD大鼠28只，其中供体大鼠8只，获取大鼠原代ADSCs-GFP，对矽肺模型大鼠进行ADSCs-GFP尾静脉注射，定期观察肺脏的绿色荧光表达情况，确定ADSCs的归巢能力。获取大鼠原代ADSCs，将20只受体大鼠随机分为空白对照组、模型组、溶剂对照组和ADSCs组，通过非暴露式气管滴注法建立矽肺大鼠模型；滴注二氧化硅24 h后，ADSCs组尾静脉注射10(6)个/kg体重的ADSC，干预28 d后观察评价肺组织病理学。通过免疫组化法检测凋亡相关蛋白Caspase-3、Bcl-2和细胞色素C，探索ADSCs对矽肺模型大鼠肺纤维化的早期干预机制。 结果： 模型组大鼠暴露于二氧化硅28 d后，具有明显的肺纤维化表现。与模型组和溶剂对照组比较，ADSCs组肺部炎症减轻、矽结节数量减少、胶原纤维沉积面积减少。免疫组化结果显示，ADSCs移植后大鼠肺组织Caspase-3、细胞色素C蛋白表达降低，Bcl-2蛋白表达增加。 结论： ADSCs回输对于延缓染矽尘大鼠早期矽肺纤维化具有明显的作用，其机制可能与调节细胞凋亡过程有关。.
Keywords: Adipose-derived mesenchymal stem cells; Apoptosis; Fibrosis; Rats; Silicosis.