miR-26a对大鼠急性全层皮肤缺损创面愈合的影响

Effect of miR-26a on wound healing of acute full-thickness skin defect in rats

目的研究miR-26a对大鼠急性全层皮肤缺损创面愈合的影响。方法 SD大鼠在大鼠背部以脊柱为中心轴线,切取全层皮肤达深筋膜层,制备急性全层皮肤缺损创面模型。将大鼠随机分为模型组、实验组,各15只。3 d后实验组大鼠于创面基底分别注射50μmol·L-1 mmu-miR-26a-5p抑制剂0.1 mL,模型组注射等量无菌生理盐水,隔天注射1次,连续观察14 d。观察大鼠模型创面愈合情况;以Masson染色观察大鼠创面组织病理学变化;以酶联免疫吸附法测定大鼠创面皮肤组织纤维连接蛋白指标水平;以蛋白质印迹(WB)法检测大鼠创面组织转化生长因子-β1(TGF-β1)、磷酸化smad3(P-smad3)蛋白表达。结果模型组、实验组治疗后7 d创面愈合率分别为(37.26±5.26)%,(45.69±2.15)%;治疗后14 d分别为(58.46±4.26)%,(75.48±4.19)%。模型组、实验组大鼠治疗后3d的创面组织纤维连接蛋白分别为(16.52±4.15),(20.46±3.15)mg·L-1;治疗后7 d分别为(26.48±6.35),(60.15±4.23)mg·L-1;治疗后14 d分别为(22.15±2.39),(55.63±3.96)mg·L-1,差异均有统计学意义(均P<0.05)。治疗后7,14 d,与模型组相比,实验组TGF-β1、P-smad3表达量升高(P<0.05);与治疗后7 d比较,治疗后14 d实验组的TGF-β1、P-smad3表达量降低(均P<0.05)。结论 miR-26a可激活TGF-β1/Smad3信号通路,诱导创面肉芽组织形成,增加创面皮肤组织中纤维连接蛋白含量,促进创面损伤修复。

Objective To investigate the effect of miR-26 a on wound healing of acute full-thickness skin defect in rats. Methods The acute full-thickness skin defect wound model was established in SD rats with spinal column as the central axis and deep fascia from the whole layer of skin to the deep fascia in the back of the rat. The rats were randomly divided into model group(n=15) and test group(n=15). Three days later, the rats in test group were injected with mmu-miR-26 a-5 p antagomir(50 μmol·L-1) 0.1 mL, and model group was injected with the same amount of aseptic normal saline once every other day, for 14 d. The wound healing of rat model was observed. Masson staining was used to observe the pathological changes of wound tissue of rats, enzyme-linked immunosorbent assay was used to detect the level of fibronectin in wound tissue of rats, and Western Bloting(WB) was used to detect the expression of transforming growth factor-β1(TGF-β1) and phosphorylated smad3(P-smad3) protein in wound tissue of rats.Results On the 7 days after treatment, the wound healing rates of model group and test group were(37. 26 ± 5. 26) %,(45. 69 ± 2. 15) %, on the 14 days after treatment, which were(58. 46 ± 4. 26) %,(75. 48 ± 4. 19) %;on the 3 days after treatment,the fibronectin in the wound tissue of model group and test group were(16. 52 ± 4. 15),(20. 46 ± 3. 15) mg · L-1;on the 7 days after treatment,which were(26. 48 ± 6. 35),(60. 15 ± 4. 23) mg·L-1;on the 14 d after treatment,which were(22. 15 ± 2. 39),(55. 63 ± 3. 96) mg·L-1,all with significant difference(all P < 0. 05). On the 7 days and 14 days after treatment,the expression of TG F-β1 and P-smad3 in test group were higher than those in model group,compared with 7 d after treatment,the expression of TGF-β1 and P-smad3 in test group were decreased on the 14 days after treatment(all P < 0. 05). Conclusion miR-26 a can activate TGF-β1/Smad3 signaling pathway,induce granulation tissue formation,increase fibronectin content in wound skin tissue,and promote wound repair.