Chen Jun-Jie, Jin Pei-Sheng, Zhao Sha, Cen Ying, Liu Yong, Xu Xue-Wen, Duan Wei-Qiang, Wang Huai-Sheng
Department of Burns and Plastic Surgery, West China Hospital, Sichuan University, Sichuan, China.
ANZ J Surg. 2011 Jun;81(6):425-30. doi: 10.1111/j.1445-2197.2010.05534.x.
Keloid is regarded as a fibroproliferative disorder with excessive accumulation of extracellular matrix. However, the molecular mechanism of keloid formation is not well understood and no treatment modality is consistently effective. Heat shock protein 47 (HSP47) is known as a collagen-specific molecular chaperone which plays a critical role in collagen biosynthesis. Results of our previous in vitro experiments demonstrated that HSP47 might be an important reason for excessive collagen accumulation in regard to keloid formation. Our objective is to investigate whether HSP47 has an influence on collagen metabolism in animal keloid models. The constructed plasmids, carrying HSP47-small hairpin RNA (shRNA), were transfected into animal keloid models, in comparison with the control groups. After transfection, the mRNA and protein expression of HSP47 and collage type I were detected by quantitative real-time PCR and Western blot. Both the mRNA and protein levels of HSP47 in animal keloid models were decreased dramatically after transfection of the HSP47- shRNA plasmid, in comparison with the control group. Following the down-regulation of HSP47, we found that the volume of animal keloid models and the major collagen expression were reduced correspondingly. Combining the results of our previous in vitro experiment results, we suggest that overexpression of HSP47 in keloid fibroblast cells could induce excessive collagen accumulation by enhancing collagen synthesis, which not only presents a possible mechanism of keloid formation, but also offers a therapeutic potential of RNA interference to HSP47 for the treatment of keloids and other fibroproliferative disorders.
瘢痕疙瘩被视为一种细胞外基质过度积聚的纤维增生性疾病。然而，瘢痕疙瘩形成的分子机制尚未完全明确，且尚无始终有效的治疗方式。热休克蛋白47（HSP47）是一种胶原特异性分子伴侣，在胶原生物合成中起关键作用。我们之前的体外实验结果表明，就瘢痕疙瘩形成而言，HSP47可能是胶原过度积聚的重要原因。我们的目的是研究HSP47在动物瘢痕疙瘩模型中是否对胶原代谢有影响。将携带HSP47小发夹RNA（shRNA）的构建质粒转染到动物瘢痕疙瘩模型中，并与对照组进行比较。转染后，通过定量实时PCR和蛋白质印迹法检测HSP47和I型胶原的mRNA及蛋白表达。与对照组相比，转染HSP47-shRNA质粒后，动物瘢痕疙瘩模型中HSP47的mRNA和蛋白水平均显著降低。在HSP47下调后，我们发现动物瘢痕疙瘩模型的体积和主要胶原表达相应减少。结合我们之前的体外实验结果，我们认为瘢痕疙瘩成纤维细胞中HSP47的过表达可通过增强胶原合成诱导胶原过度积聚，这不仅提出了瘢痕疙瘩形成的一种可能机制，也为RNA干扰HSP47治疗瘢痕疙瘩及其他纤维增生性疾病提供了治疗潜力。
