进行性系统性硬化症皮损中前胶原基因和SMADmRNA的表达

mRNA expression of procoilagen and SMADs in lesional skin of progressive systemic sclerosis

目的探讨进行性系统性硬化症(PSS)硬化皮肤组织中Ⅰ型和Ⅲ型前胶原基因以及细胞内信号转导分子 SMAD mRNA 的表达情况,分析它们在发病机制中的作用。方法用荧光实时定量聚合酶链反应法分别检测11例 PSS 患者硬化皮损及11例正常对照皮肤组织中Ⅰ型和Ⅲ型前胶原基因以及不同类型 SMAD(SMAD2、SMAD3、SMAIM、SMAD7)mRNA 的表达水平。结果Ⅰ型前胶原基因α1、Ⅲ型前胶原基因α1、SMAD4及 SMAD7的 mRNA 在硬化皮损中的表达明显高于在正常皮肤组织的表达,差异有统计学意义(均 P<0.05)。SMAD4 mRNA 的表达与Ⅰ型、Ⅲ型前胶原基因α1mRNA 的表达成正相关(r 值分别为0.728和0.678,均 P<0.05)。SMAD3 mRNA 的表达与Ⅰ型前胶原基因α1 mRNA 的表达成正相关(r=0.859,P<0.01)。结论 PSS 硬化皮肤组织中存在有 SMAD4mRNA 的高表达,可能是导致Ⅰ型、Ⅲ型胶原在硬化组织中过度堆积的原因之一。

Objective To investigate the mRNA expression of type Ⅰ and type Ⅲ procollagen and SMADs in the lesional skin of progressive systemic sclerosis （PSS） and analyze the role in pathogenesis of scleroderma thereof. Methods Real time PCR was used to detect the mRNA expression of type Ⅰand type Ⅲ procollagen, and SMADs （ SMAD 2, SMAD 3, SMAD 4, and SMAD 7 ） in the lesional skin specimens of 11 patients with PSS and 11 specimens of normal skin. Results Type Ⅰ procollagen α1 , type Ⅲ procollagen α1 , SMAD 4, and SMAD 7 were expressed at the mRNA level significantly higher in the lesional skin tissues of the PSS patients than in the normal skin tissues （ all P 〈 0.05 ）. SMAD 4 mRNA expression was positively correlated with type Ⅰ procollagen α1 mRNA expression （ r = 0. 728, P 〈 0.05 ） and the type Ⅲprocollagen α1 mRNA expression （ r = 0. 678, P 〈 0.05 ）. SMAD3 mRNA expression was positively correlated with the type Ⅰ procollagen α1 mRNA expression （r = 0.859, P 〈 0.01 ）. Conclusion Increased SMAIM mRNA in the lesional skin of systemic sclerosis is positively correlation with increased type Ⅰ and type Ⅲ procollagen α1 mRNA expression and may be one of the main pathogenesis in resulting in excessive type Ⅰ and type Ⅲ collagen accumulation in PSS lesional skin.