富血小板血浆凝胶促进大鼠深Ⅱ度烧伤创面愈合的机制研究

Study on the Mechanism of Platelet-rich Plasma Gel in Promoting Wound Healing of Deep Second Degree Burn in Rats

目的:通过建立大鼠深Ⅱ度烧伤模型,观察富血小板血浆凝胶对烧伤创面的治疗效果及其对烧伤创面巨噬细胞表型的影响,初步探究富血小板血浆凝胶促进烧伤创面愈合的机制。方法:选择SPF级雄性SD大鼠30只,其中12只用于制作富血小板血浆凝胶,另外18只建立深Ⅱ度烫伤模型,随机分为实验组和对照组。实验组创面涂抹富血小板血浆凝胶治疗,隔日给药1次。对照组给予等量生理盐水涂抹后,凡士林纱布覆盖。分别于治疗后第3、7、14天创面拍照观察创面愈合情况,HE染色观察创面炎症细胞浸润情况,免疫组化方法观察M1、M2型巨噬细胞表型标记物诱导型一氧化氮合酶(iNOS)、CD206阳性细胞数目,qPCR检测炎症因子TNF-α及抗炎因子IL-10、TGF-βmRNA的相对表达量。结果:两组大鼠的创面愈合率均随着观察时间延长而升高,治疗后第3、7、14天实验组愈合率高于对照组,差异具有统计学意义(P<0.05)。治疗后第3、7、14天实验组炎症细胞数目低于对照组,差异具有统计学意义(P<0.05)。治疗后第3、7、14天iNOS阳性细胞实验组均明显低于对照组,CD206阳性细胞实验组均明显高于对照组,差异均具有统计学意义(P<0.05)。治疗后第3、7、14天实验组创面组织TNF-α mRNA表达均低于对照组,而IL-10 mRNA在第3,7,14天均高于对照组,差异具有统计学意义(P<0.05);实验组TGF-βmRNA在第3天高于对照组,而第7、14天低于对照组,差异具有统计学意义(P<0.05)。结论:富血小板血浆凝胶可有效促进大鼠深Ⅱ度烧伤创面愈合,可能与减少创面炎症细胞浸润,调节创面炎症反应及巨噬细胞表型有关。

Objective To investigate the mechanism of platelet-rich plasma gel promoting burn wound healing by establishing rat model of deep Ⅱ degree burn and observing the effect of platelet rich plasma gel on burn wound healing and macrophage phenotype.Methods Thirty male SD rats of SPF grade were selected,of which 12 were used to make platelet rich plasma gel,and the other 18 were used to establish deep Ⅱ degree scald model.They were randomly divided into the experimental group and the control group.In the experimental group,the wound was treated with platelet-rich plasma gel,once every other day.The control group was coated with vaseline gauze after equal amount of normal saline.Wound healing was observed on day 3,7 and 14,respectively.HE staining was used to observe the infiltration of inflammatory cells on the wound.Immunohistochemical method was used to observe the number of iNOS and CD206 positive cells of phenotypic markers of M1 and M2 macrophages.qPCR was used to detect the relative expression levels of inflammatory factor TNF-α and anti-inflammatory factors IL-10 and TGF-βmRNA.Results The wound healing rate of two groups were increased with prolonged observation,the wound healing rate in the experimental group were higher than those of the control group on the 3rd,7th and 14th days after treatment,the differences were statistically significant (P<0.05).The number of inflammatory cells in the experimental group was lower than those in the control group on the 3rd,7th and 14th days after treatment (P<0.05).The iNOS positive cells in the experimental group were significantly lower than the control group,and the CD206 positive cells in the experimental group were significantly higher than the control group on the 3rd,7th and 14th days after treatment (P<0.05).The mRNA expression of TNF-α in wound tissue in the experimental group was lower than those in the control group on the 3rd,7th and 14th days after treatment (P<0.05).While the mRNA expression of IL-10 was higher than those in the control group on the 3rd,7th and 14th days after treatment (P<0.05).TGF-βmRNA in the experimental group was higher than that in the control group on the 3rd days after treatment,and lower than those in the control group on the 7th and 14th days after treatment(P<0.05).Conclusion PRP gel can effectively promote the wound healing of rats with deep second-degree burn,which may be related to reducing the infiltration of inflammatory cells on the wound surface,regulating the inflammatory response of the wound surface and the phenotype of macrophages.