臭氧气浴对深Ⅱ度烧伤大鼠创面病理变化及组织细胞因子表达的影响

目的:探讨臭氧气浴干预对大鼠深Ⅱ度烧伤创面的病理变化及局部组织中细胞因子血小板源性生长因子(PDGF)、转化生长因子β_3(TGF-β_3)和肿瘤坏死因子α(TNF-α)表达的影响。方法:取80只雄性清洁级SD大鼠,随机分为臭氧气浴实验组和常规换药对照组各40只。建立背部深Ⅱ度烧伤模型,伤后3 d、7 d、14 d和21d,2组创面分别取材检测。创面常规换药,对照组的创面以生理盐水清洗和碘伏油纱包扎,隔日换药1次;臭氧气浴实验组在换药前将大鼠放入清洁泡沫盒内,打开臭氧发生器开关,以输出浓度为50 mg/L的臭氧熏蒸创面20min,关闭开关,再行创面常规换药,隔日1次,直至愈合。各时点每组大鼠创面打开时取1次创面中心组织标本,然后实验组行生理盐水棉球轻拭创面和臭氧气熏蒸,对照组仅用生理盐水棉球轻拭创面后再分别取材1次。标本行HE染色组织学观察和免疫组化染色半定量观察,结合图像数据分析及ELISA法检测2组创面组织中细胞因子PDGF、TGF-β_3和TNF-α含量。结果:创面大体观察可见,臭氧气浴实验组的创面平整,边缘清晰,炎性反应轻,肿胀和渗出程度均较对照组弱,创面愈合率高于常规换药对照组,2组比较差异有统计学意义。显微镜下观察HE染色组织可见臭氧气浴实验组的创面各时点炎性反应程度比常规换药对照组轻,而新生毛细血管、成纤维细胞和上皮细胞增生数量明显优于常规换药对照组。与对照组比较,臭氧气浴实验组各时点烧伤大鼠的创面组织匀浆上清液中PDGF和TGF-β_3表达量均高于常规换药对照组,而TNF-α表达量明显低于对照组,2组比较差异均有统计学意义。结论:臭氧气浴疗法干预大鼠深Ⅱ度烧伤创面,能改善局部病理变化,促进与创面愈合相关的细胞因子PDGF和TGF-β_3表达,同时减轻炎性介质TNF-α的表达。

Effect of ozone bath on pathological changes and expression of cytokines in rats with deep second-degree burns

AIM: To investigate the effect of ozone bath on the pathological changes and the expression of cytokines, platelet-derived growth factor (PDGF), transforming growth factor-β₃ (TGF-β₃), and tumor necrosis factor-α (TNF-α), in the wounds of deep second-degree burns in rats. METHODS: Male clean-grade SD rats (n=80) were randomly divided into 2 groups, ozone bath group and routine dressing group (control group), with 40 rats in each group. Deep second-degree burn wound was established on the back of the rats, and then the examinations were conducted at 3 d, 7 d, 14 d and 21 d after burn. For the routine dressing group, the wound was cleaned by normal saline and covered with iodophor vaseline gauze every 2 d. For the ozone bath group, before the dressing, the rats were put into the clean foam box to accept ozone fumigation for 20 min (50 mg/L), and then accepted dressing change as the same as that in control group every 2 d. At each time point, the tissue specimens from these rat wounds (at wound center) were taken. The rats in ozone bath group received cleaning by saline cotton and then the ozone bath fumigation, while the rats in control group only received cleaning by saline. After that, the tissue specimens were taken again for HE staining, immunohistochemical staining and semiquantitative observation combined with image data analysis. The concentrations of the cytokines PDGF, TGF-β₃ and TNF-α in the wound were measured by double-antibody sandwich ELISA. RESULTS: In ozone bath group, the wounds were smooth with clear edge and slight inflammatory reaction, swelling and exudation were weaker, and the wound healing rate was higher than that in control group with significant difference. Under microscopic observation with HE staining, slighter inflammatory reaction in ozone bath group was observed than that in control group at each time point, and the numbers of fresh capillaries, fibroblasts and epithelial cells were significantly larger than those in control group. The expression levels of PDGF and TGF-β₃ in the wound tissue homogenate in ozone bath group were higher, and the expression level of TNF-α was significantly lower than those in control group at each time point with significant difference. CONCLUSION: The ozone bath therapy improves the local pathological changes and promotes the expression of cytokines PDGF and TGF-β₃, which are associated with wound healing, as well as reduces the expression of inflammatory mediator TNF-α in the rats with deep second-degree burns, thus promoting the wound healing and anti-inflammatory responses.