负载VEGF、bFGF的聚乳酸-羟基乙酸纳米微囊复合体对放射性损伤创面愈合的作用

Effect of PLGA scaffold incorporating VEGF and bFGF loaded nanoparticles on wound healing in case of radiation injury

目的探讨负载VEGF、bFGF的聚乳酸-羟基乙酸共聚物(poly lactic-co-glycolic acid,PLGA)纳米微囊复合体对放射性损伤创面愈合的影响。方法以PLGA为支架联合应用bFGF、VEGF构建纳米微囊,作用于小鼠放射性损伤创面作为实验组,单纯应用PLGA为支架,未用bFGF、VEGF的作为对照组,观察两组创面愈合率、创面的病理改变;于伤后不同时间点检测创面新生血管细胞数目、毛细血管截断面积及成纤维细胞数量; RT-PCR检测创面VEGF mRNA、bFGF mRNA的表达水平;观察其对放射性创面愈合的影响。结果实验组创面愈合率明显高于对照组;实验组创面组织中VEGF mRNA、bFGF mRNA的表达均高于对照组,差异均有统计学意义(P <0. 05);对创面组织进行HE染色,发现实验组肉芽组织增多增厚,成纤维细胞数量及密度均高于对照组;伤后第8天、第15天,实验组的新生毛细血管数量及毛细血管横截面积均较对照组有所增加,实验组的成纤维细胞计数也明显高于对照组,差异均有统计学意义(P <0. 05)。结论采用负载VEGF、bFGF的PLGA纳米微囊复合体可以促进小鼠放射性损伤创面的愈合。

Objective To study the effects of poly lactic-co-glycolic acid（ PLGA） scaffold incorporating VEGF and bFGF loaded nanoparticle complexes on the healing of murine radioactive wounds. Methods Mice undergoing combined application of PLGA and VEGF/bFGF loaded nanoparticle complexes against radioactive wounds were assigned to the experimental group,while those among whom PLGA alone was used to treat radioactive wounds were considered the control group. The wound healing rate and pathological changes of the wounds were observed,while the number of new vascular cells,the area of capillary interception and the number of fibroblasts were detected at different time points after injury between the two groups. Results With regard to the wound surface of mice with radiation injury,the wound healing rate of the experimental group was significantly higher than that of the control group after the combined application of bFGF and VEGF. The expressions of VEGF mRNA and bFGF mRNA in wound tissue of the experimental group were higher than those of the control group,and there was significant difference between the two groups（ P〈0. 05）. HE staining performed on the wound tissue suggested that the granulation tissue in the experimental group increased and thickened,and the number and density of fibroblasts were better than those of the control group. Eight and fifteen days after injury,the number and the cross-sectional area of newborn blood capillaries were both increased in the experimental group compared with the control group,so was the number of fibroblasts. Conclusions PLGA nanoparticle complexes loaded with VEGF and bFGF can promote the healing of radioactive wounds in mice.