Xie Xiao-Ying, Yang Chuan, Ren Meng, Hao Shao-Yun, Zhu Ping, Yan Li
Department of Endocrinology and Metabolism, The Second Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
J Am Podiatr Med Assoc. 2012 Jul-Aug;102(4):299-308. doi: 10.7547/1020299.
Matrix metalloproteinases (MMPs) degrade extracellular matrix components. Increased MMP-9 content in diabetic skin contributes to skin vulnerability and refractory foot ulcers. To identify ways to decrease MMP-9 levels in skin, inhibition of MMP-9 expression in dermal fibroblasts using small interfering RNA was investigated in vitro.
A full-thickness wound was created on the midback of streptozotocin-induced diabetic rats; skin biopsies were performed 3 days later. Skin MMP-9 expression was observed by immunohistochemical analysis. Dermal fibroblasts from 1-day-old normal Sprague Dawley rats cultured with high glucose and homocysteine concentrations were transfected with small interfering RNA complexes. Cells were collected 30, 48, and 72 hours after transfection, and reverse transcription-polymerase chain reaction, Western blot analysis, and gelatin zymography for MMP-9 were performed.
Expression of MMP-9 was increased in diabetic rat skin, especially around wounds. After 30-, 48-, and 72-hour transfection with each MMP-9-specific small interfering RNA, reverse transcription-polymerase chain reaction showed markedly decreased MMP-9 messenger RNA expression, protein abundance, and activity. Of four MMP-9 small interfering RNAs, one sequence had a stable high inhibition rate (>70% at 30 and 48 hours after transfection).
Expression of MMP-9 was increased in diabetic rat skin, especially around wounds, and was markedly inhibited after MMP-9 small interfering RNA transfection in vitro (P < .05). These findings may provide new treatments for diabetic skin wounds.
基质金属蛋白酶（MMPs）可降解细胞外基质成分。糖尿病皮肤中MMP - 9含量增加会导致皮肤易损性增加及难治性足部溃疡。为确定降低皮肤中MMP - 9水平的方法，体外研究了使用小干扰RNA抑制真皮成纤维细胞中MMP - 9的表达。
在链脲佐菌素诱导的糖尿病大鼠背部中部制造全层伤口；3天后进行皮肤活检。通过免疫组织化学分析观察皮肤MMP - 9的表达。用小干扰RNA复合物转染1日龄正常Sprague Dawley大鼠在高葡萄糖和高同型半胱氨酸浓度下培养的真皮成纤维细胞。转染后30、48和72小时收集细胞，并进行逆转录 - 聚合酶链反应、蛋白质印迹分析以及MMP - 9的明胶酶谱分析。
糖尿病大鼠皮肤中MMP - 9的表达增加，尤其是在伤口周围。用每种MMP - 9特异性小干扰RNA转染30、48和72小时后，逆转录 - 聚合酶链反应显示MMP - 9信使核糖核酸表达、蛋白质丰度和活性明显降低。在四种MMP - 9小干扰RNA中，一种序列具有稳定的高抑制率（转染后30和48小时>70%）。
糖尿病大鼠皮肤中MMP - 9的表达增加，尤其是在伤口周围，并且在体外转染MMP - 9小干扰RNA后受到明显抑制（P <.05）。这些发现可能为糖尿病皮肤伤口提供新的治疗方法。
