胎盘间充质干细胞治疗小鼠烫伤愈合的相关研究

目的:观察胎盘间充质干细胞对TGF-β1/Smad信号通路的调控作用,探讨胎盘间充质干细胞对烫伤愈合及瘢痕形成的影响。方法:构建小鼠烫伤模型,注射人胎盘间充质干细胞(hPMSCs),荧光显微镜观察小鼠创伤皮肤组织中hPMSCs细胞的存活情况;HE和Masson染色观察小鼠创伤皮肤的变化;Western blot检测观察创伤皮肤TGF-β1、p-Smad3、Smad7、α-SMA、collagen I、Collagen III蛋白表达变化。结果:注射hPMSCs细胞后,小鼠创伤面积逐渐减小,创伤愈合率逐渐增加;hPMSCs细胞分布在小鼠创伤皮肤组织中,存活状况较好。进一步研究发现烫伤模型组皮肤表层细胞受损脱落,真皮层组织疏松,毛囊、皮脂腺等附属器坏死,可见明显的毛细血管扩张,并伴有炎性细胞渗出,同时可见大量的成纤维细胞增生和胶原纤维形成;注射hPMSCs细胞治疗后,病理改变、纤维增生和胶原形成明显减轻;此外,烫伤模型组创伤皮肤组织中TGF-β1、p-Smad3表达明显上调,Smad7蛋白表达明显下调,α-SMA、collagen I、Collagen III表达明显上调。经hPMSCs细胞治疗后,TGF-β1、p-Smad3蛋白表达明显下调,Smad7蛋白表达明显上调,α-SMA、collagen I、Collagen III蛋白表达明显下调。结论:胎盘间充质干细胞可能通过抑制TGF-β1/Smad信号通路,发挥促进烫伤愈合且抑制瘢痕形成的作用。

The Effect of Placental Mesenchymal Stem Cells on Scald Healing in Mice

Objective:To observe the regulation of placental mesenchymal stem cells on TGF-β1/Smad signaling pathway,and to explore the effect of placental mesenchymal stem cells on scald healing and scar formation.Methods:We constructed mouse scald model and injected hPMSCs cells into the scald mice.The survival of hPMSCs in the wounded skin tissues of mice was observed by fluorescence microscopy and the changes of wounded skin in mice by HE and Mason staining,meanwhile the expression of TGF-β1,p-Smad3,Smad7,α-SMA,collagen I and Collagen III protein in wounded skin was detected by Western blot.Results:The wound area of mice was decreased gradually,and the wound healing rate was increased gradually after injected into hPMSCs;The distribution of hPMSCs in the wounded skin tissue of mice was observed under fluorescence microscope,and the survival condition was better;Further research found that skin surface cells were damaged and exfoliated,dermal tissue was loose,hair follicles,sebaceous glands and other appendages were necrotic,and obvious telangiectasis was observed,accompanied by inflammatory cell exudation and a large number of fibroblast proliferation and collagen fibers were observed in the scald model group,After injection of hPMSCs,pathological changes,Fibrous proliferation and collagen formation were significantly alleviated;the expressions of TGF-β1 and p-Smad3 was significantly higher,the expression of Smad7 protein was significantly lower,meanwhile the expressions of proteinsα-SMA,collagen I and Collagen III were significantly increased in scald model group;while the expressions of TGF-β1 and p-Smad3 was significantly lower and the expression of Smad7 protein was significantly higher andα-SMA,collagen I and Collagen III were significantly decreased after injection of hPMSCs.Conclusion:Placental mesenchymal stem cells may promote scald healing and inhibit scar formation by inhibiting TGF-β1/Smad signaling pathway.