基于TGF-β1/Smad3信号通路观察rb-bFGF在糖尿病大鼠烧伤创面愈合中的作用机制

The role of rb-bFGF in burn wound healing of diabetic rats based on TGF-β1/Smad3 signal pathway

目的基于TGF-β1/Smad3信号通路探讨重组牛碱性成纤维细胞生长因子(rb-bFGF)在糖尿病(DM)烧伤创面愈合中的作用机制。方法2018年年3月—9月于成都医学院第一附属医院科研实验中心进行实验,SD大鼠100只随机数字表法分为对照组、模型组、TGF-β1组、实验组,各25只,除对照组外其余大鼠腹腔注射链脲佐菌素(STZ)构建糖尿病模型,建模后第10天采用直径为2.5 cm的圆形烫伤仪探头烫伤所有大鼠皮肤。伤后对照组、模型组不进行药物干预;TGF-β1组烫伤创面下注射5 ng/ml TGF-β10.5 ml;实验组涂抹rb-bFGF。观察各组伤后体征和愈合情况,并在28天后处死动物;分别采用HE染色、电镜、免疫荧光、Western-blot法观察和检测创面组织的形态变化、超微结构、α-平滑肌肌动蛋白(α-SMA)、TGF-β1、Smad3蛋白表达。结果与对照组比较,模型组大鼠创面愈合率、α-SMA、TGF-β1和Smad3蛋白的表达明显降低(t/P=19.697/0.000、8.643/0.000、4.632/0.002、9.493/0.002);与模型组比较,TGF-β1组、实验组大鼠创面愈合率、α-SMA、TGF-β1和Smad3蛋白表达升高(F/P=12.397/0.000、15.392/0.000、16.283/0.000、28.832/0.000),TGF-β1组、实验组比较差异无统计学意义(P>0.05)。HE染色及电镜结果表明,与对照组比较,模型组大鼠炎性细胞明显增多,未见毛细血管新生;与模型组比较,TGF-β1组、实验组均出现成纤维细胞致密分布,新生毛细血管少量出现。结论rb-bFGF具有促进糖尿病烧伤创面愈合的作用,其机制可能是rb-bFGF激活TGF-β1/Smad3信号通路,致使其下游基因蛋白表达提高。

Objective Based on the TGF-β1/Smad3 signal pathway,the mechanism of recombinant bovine basic fibroblast growth factor(rb-bFGF)in DM burn wound healing was studied.Methods From March 2018 to September 2018,the experiment was conducted in the research and experiment center of the First Affiliated Hospital of Chengdu Medical College,a total of 100 SD rats were randomly divided into control group,model group,TGF-β1 group and experimental group.In addition to the control group,streptozotocin(STZ)was injected intraperitoneally to construct a diabetes model.On the 10th day after modeling,a circular scalder probe with a diameter of 2.5cm was used to scald the skin of all rats..In TGF-β1 group,5ng/ml TGF-β1 was injected under the scald wound The dose was 0.5ml and rb-bFGF was applied in the experimental group.After 28 days,the animals were killed.He staining,electron microscopy,immunofluorescence and Western blot were used to observe and detect the morphological changes,ultrastructure,α-smooth muscle actin(α-SMA),TGF-β1 and Smad3 protein expression of the wound tissue.Results From March to September 2018,the experiment was carried out in the scientific research and experimental center of the First Affiliated Hospital of Chengdu Medical College.100 SD rats were randomly divided into control group,model group,TGF-β1 group and experimental group with 25 rats each.The diabetic model was established by intraperitoneal injection of streptozotocin(STZ)in all rats except the control group.On the 10th day after modeling,the skin of all rats was scalded with a 2.5cm diameter circular scald probe.After injury,the control group and model group did not receive drug intervention.In the TGF-β1 group,5 ng/ml TGF-β110.5 ml was injected into the burn wound,and Rb bFGF was applied in the experimental group.The physical signs and healing of each group were observed.After 28 days,the animals were killed,and the morphological changes,ultrastructure,expression ofα-SMA,TGF-β1 and Smad3 were observed and detected by HE staining,electron microscopy,immunofluorescence and Western blot.Conclusion Rb bFGF can promote the healing of diabetic burn wounds,and its mechanism may be that rb bFGF can activate TGF-β1/Smad3 signal pathway,resulting in the expression of downstream gene protein.