GHK-Cu螯合物通过减轻上皮细胞损伤对博来霉素诱导肺纤维化的保护性作用

Protective effect of GHK-Cu in bleomycin-induced pulmonary fibrosis reducing epithelial cell damage

目的研究GHK-Cu螯合物对特发性肺纤维化小鼠肺组织的保护作用,并探究可能的作用机制。方法实验性研究。采用气管灌注法给予博来霉素(3 mg/kg),制备C57BL/6小鼠肺纤维化模型。每隔一天,腹腔注射2种高低不同剂量的GHK-Cu,剂量分别为0.2μg/g和20μg/g。苏木素-伊红染色观察肺组织形态变化以及肺损伤情况;Masson染色观察肺组织纤维化和胶原沉积情况;免疫组织化学染色观察上皮相关指标E-cadherin的表达情况,蛋白免疫印迹分析转化生长因子β1(TGF-β1)信号通路和上皮-间充质转化上皮相关蛋白的表达情况。采用酶联免疫吸附试验测定肺组织匀浆中TGF-β1的水平。结果与正常对照组相比,博来霉素组小鼠肺组织肺泡被破坏,肺泡空间增大,严重变形增厚,肺泡壁增厚,肺泡骨架受损,呈现出扭曲的肺部结构,肺泡空间炎性细胞和成纤维细胞浸润,胶原沉积增多,肺组织中TGF-β1、α-平滑肌肌动蛋白表达增多,E-cadherin表达减少。GHK-Cu螯合物可以减轻博来霉素诱导的小鼠肺组织纤维化,能减轻肺部损伤、炎症浸润、胶原沉积以及增加E-cadherin的表达,且这些改变程度与GHK-Cu剂量不相关。结论GHK-Cu螯合物可以减轻博来霉素诱导的肺泡上皮损伤,进而减轻肺纤维化,这一作用可能与抑制TGF-β1信号通路相关。

Objective To study the effect of GHK-Cu chelates in the improvement of idiopathic pulmonary fibrosis in mice for the possible mechanism.Methods This was an experimental research.BLM(3 mg/kg)was administered by tracheal perfusion,and pulmonary fibrosis model of C57BL/6 mice was induced after 21 days.Intraperitoneal injection of different doses of GHK-Cu(0.2μg/g and 20μg/g)was performed every other day.Hematoxylin-Eosin(HE)staining was used to observe the morphological changes of lung tissue and lung injury.The fibrosis and collagen deposition were observed by Masson trichromatic staining.Immunohistochemistry fluorescence chemical staining and Western blot were used to analyze the expression of TGF-β1 signaling pathway and epithelial-related proteins.ELISA was used to determine the level of TGF-β1 in lung tissue homogenate.Results Compared with the control group,the alveolar in the model group were destroyed,the alveolar space was enlarged,the alveolar walls were thickened,the alveolar skeleton was damaged,the alveolar space was infiltrated with inflammatory cells and fibroblasts,collagen deposition was increased,the expression of TGF-β1 andα-SMA in lung tissue increases,and the expression of E-cadherin decreases.GHK-Cu chelate can alleviate BLM-induced lung fibrosis in mice,reduce lung injury,inflammatory infiltration,collagen deposition,and increase E-cadherin expression,and the degree of these changes is not related to the dose of GHK-Cu.Conclusions GHK-Cu chelate can reduce BLM-induced alveolar epithelial damage,thereby reducing pulmonary fibrosis.This effect may be related to the inhibition of TGF-β1 signaling pathway.