MicroRNAs (miRNAs) are well-known candidates for modulating the dysregulated signaling pathways during fibrosis. In this study, we investigated the expression pattern of 16 miRNAs, which have previously been confirmed or predicted to target genes involved in extracellular matrix (ECM) homeostasis. Primary culture of dermal fibroblasts was obtained from skin biopsies of diffused cutaneous SSc (dcSSc) patients and healthy controls. Expression of let-7a, miR-1, miR-15a, miR-17, miR-19a, miR-20a, miR-21, miR-27b, miR-26a, miR-29a, miR-29b, miR29c, miR-141, miR-125a-5p, miR-193a-3p, and miR-200a were quantified by Real-time PCR. Functional analysis of microRNAs was performed using synthetic oligonucleotides. To further confirm the pro- or anti-fibrotic effects of miRNAs, normal fibroblasts were treated with 10 ng/mL of transforming growth factor (TGF)-β to generate an in vitro model of dermal fibrosis. miR-21 and miR-29a were upregulated and downregulated, respectively, in both dcSSc and TGF-β-treated fibroblasts. We observed that restoration of miR-29a expression or blockade of miR-21 function negatively affected collagen production. COL1A1 expression in SSc fibroblasts is more sensitive to changes of miR-29a and miR-21 expression in compare to normal fibroblasts. miR-29a alone was effective to decrease TGF-β-induced collagen production in dermal fibroblasts. miR-21 and TGF-β had synergistic effects on induction of collagen production. However, neither miR-21 nor miR-29a affected alpha smooth muscle actin (α-SMA) expression in the presence or absence of TGF-β in dermal fibroblasts. miR-21 and miR-29a as pro- and anti-fibrotic miRNAs modulate collagen production in an opposing manner. Focusing on miR-21 and miR-29s as therapeutic targets would be effective in patients with SSc or other fibrotic diseases which show aberrant expression of collagen expression.

中文翻译：

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MicroRNA-21和microRNA-29a调节系统性硬化症患者真皮成纤维细胞中胶原蛋白的表达。

MicroRNA（miRNA）是在纤维化过程中调节失调的信号通路的著名候选者。在这项研究中，我们调查了16种miRNA的表达模式，这些miRNA先前已被确认或预测为靶向参与细胞外基质（ECM）稳态的基因。皮肤成纤维细胞的原代培养是从弥漫性皮肤SSc（dcSSc）患者和健康对照组的皮肤活检中获得的。let-7a，miR-1，miR-15a，miR-17，miR-19a，miR-20a，miR-21，miR-27b，miR-26a，miR-29a，miR-29b，miR29c，miR- 141，miR-125a-5p，miR-193a-3p和miR-200a通过实时PCR定量。使用合成的寡核苷酸对microRNA进行功能分析。为了进一步确认miRNA的促纤维化或抗纤维化作用，正常成纤维细胞用10 ng / mL转化生长因子（TGF）-β处理，以生成真皮纤维化的体外模型。在dcSSc和TGF-β处理的成纤维细胞中，miR-21和miR-29a分别被上调和下调。我们观察到恢复miR-29a表达或阻断miR-21功能会对胶原蛋白产生负面影响。与正常成纤维细胞相比，SSc成纤维细胞中的COL1A1表达对miR-29a和miR-21表达的变化更敏感。单独的miR-29a可以有效减少皮肤成纤维细胞中TGF-β诱导的胶原蛋白生成。miR-21和TGF-β对诱导胶原蛋白的产生具有协同作用。但是，在皮肤成纤维细胞中存在或不存在TGF-β的情况下，miR-21和miR-29a都不影响α平滑肌肌动蛋白（α-SMA）的表达。miR-21和miR-29a作为促纤维化和抗纤维化的miRNA，以相反的方式调节胶原蛋白的产生。专注于miR-21和miR-29s作为治疗靶标在SSc或其他纤维化疾病中表现出胶原蛋白表达异常的患者将是有效的。