负荷缓释VEGF的人工真皮对大鼠深Ⅱ度烧伤创面修复及细胞凋亡的影响

Effect of artificial dermis loaded with sustained release VEGF on wound healing and apoptosis of rats with deep second degree burn

目的研究负荷缓释血管内皮生长因子(VEGF)的人工真皮对大鼠深Ⅱ度烧伤创面修复及细胞凋亡的影响。方法选择20只成年雄性SD大鼠并制备深Ⅱ度烧伤模型,按随机数字表法分为普通人工真皮修复的对照组、负荷缓释VEGF人工真皮修复的VEGF组,每组各10只。干预后第7天、第14天时观察创面修复情况并计算愈合率;干预后第14天收集创面组织,检测VEGF、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关x蛋白(Bax)、裂解型含半胱氨酸的天冬氨酸蛋白水解酶-3(Cleaved caspase-3)的表达水平及微血管密度、细胞凋亡率。结果VEGF组大鼠干预后第7天、第14天时的创面愈合率为(48.57±9.39)%、(81.38±13.29)%,高于对照组[(29.39±5.69)%、(54.57±9.18)%],干预后第14天时创面组织中VEGF、Bcl-2的表达水平及微血管密度为1.19±0.25、0.91±0.17、(54.29±8.39)个/mm^(2),均高于对照组[0.62±0.11、0.38±0.08、(37.47±7.68)个/mm^(2)],Bax、Cleaved caspase-3的表达水平及细胞凋亡率为0.30±0.07、0.38±0.08、(12.50±1.25)%,均低于对照组[0.93±0.18、0.85±0.16、(30.00±1.50)%],差异均有统计学意义(P<0.05)。结论负荷缓释VEGF的人工真皮显著促进大鼠深Ⅱ度烧伤创面修复,促进微血管形成、抑制细胞凋亡是与之相关的分子机制。

Objective To study the effect of artificial dermis loaded with sustained release vascular endothelial growth factor(VEGF)on wound healing and apoptosis of rats with deep second degree burn.Methods Twenty adult male Sprague Dawley rats were selected to establish deep second degree burn model,then randomly divided into the control group treated with normal artificial dermis,and the VEGF group treated with artificial dermis loaded with sustained release VEGF,each group 10 rats.On the 7th and 14th day after intervention,wound healing was observed and healing rate was calculated.On the 14th day after intervention,the expression of VEGF,B-cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax),Cleaved cysteinyl aspartate specific proteinase-3(Cleaved caspase-3),microvessel density and apoptosis rate in wound tissues were detected.Results The wound healing rate of rats in the VEGF group on the 7th and 14th day after intervention was(48.57±9.39)%and(81.38±13.29)%,which were higher than those of the control group[(29.39±5.69)%,(54.57±9.18)%],the expression levels of VEGF and Bcl-2 and microvessel density in wound tissue on the 14th day after intervention were 1.19±0.25,0.91±0.17,(54.29±8.39)/mm^(2),which were higher than those of the control group[0.62±0.11,0.38±0.08,(37.47±7.68)/mm^(2)],the expression level of Bax and Cleaved caspase-3 and the apoptosis rate were 0.30±0.07,0.38±0.08,(12.50±1.25)%,which were lower than those of the control group[0.93±0.18,0.85±0.16,(30.00±1.50)%],the differences were statistically significant(P<0.05).Conclusion The artificial dermis loaded with sustained release VEGF can significantly promote the repair of deep second degree burn wounds in rats,and promoting angiogenesis and inhibiting apoptosis are related molecular mechanisms.