马桑提取物促进大鼠烧伤创面愈合的作用和机制

 目的：探讨马桑提取物(CSME)对大鼠烧伤创面愈合的影响及机制。方法：随机将40只SD雄性大鼠分成生理盐水（NS）组、白凡士林（WPJ）组、磺胺嘧啶银（SSD）组和CSME组，每组10只。将大鼠麻醉后，制备背部深Ⅱ度皮肤烧伤创面。而后分别用NS敷料、WPJ敷料、SSD敷料和CSME敷料覆盖治疗21 d。在第1 d、3 d、7 d、14 d和21 d，观察动物的临床症状和创面状况（上皮化速率、结痂及被毛等）后，分别取出创面组织，用于组织学观察，检测丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性，检测表皮生长因子（EGF）和碱性成纤维细胞因子（bFGF）蛋白水平及胶原mRNA表达。结果：CSME组新生上皮生长高度活跃，有大量新生被毛生长，创面上皮化速率明显高于其它各组 (P<0.05)。SSD组创面中央新生被毛稀疏而细小，而CSME组创面中央被毛密集，大部分被毛接近正常。CSME组镜下可见全部被多层上皮细胞覆盖，新生胶原纤维充分分化，排列整齐，组织结构明朗，皮脂腺和毛囊增生极其活跃等，显著优于其它各组。本研究显示，烧伤后从第1 d到21 d，CSME组早期EGF和bFGF水平显著高于其它各组，后期迅速下降，低于其它组（P<0.05或P<0.01）。SSD组Ⅰ型与Ⅲ型胶原mRNA表达的比值显著高于其它各组和正常组织，CSME治疗组显著低于其它各组和正常组织(P<0. 05)。结论：本研究表明，CSME可诱导烧伤创面无瘢痕愈合。CSME的这种作用与其早期增强EGF和bFGF蛋白水平，后期抑制两者的水平有关,也可能与其抑制烧伤创面Ⅰ型胶原而增强Ⅲ型胶原mRNA表达密切相关。

Coriaria sinica Maxim extract promotes burn wound healing in rats

AIM：To investigate the effects of Coriaria sinica Maxim extract (CSME) on burn wound healing in rats. METHODS：Forty male SD rats were randomly divided into normal saline (NS) group, white petrolatum jelly (WPJ) group, silver sulfadiazine (SSD) group and CSME group. After the animals were anesthetized, the skin of their backs was burnt to induce deep Ⅱ degree burn wounds. These wounds were treated respectively for 21 d by covering dressings with NS, WPJ, SSD and CSME, respectively. On the 1st, 3rd, 7th, 14th and 21st days, after the clinical symptoms of the animals and conditions of the wounds such as the epithelization rate, crusting and hair growth were observed, the wound tissues were also taken for histological examination. The content of malondialdehyde (MDA), the activity of superoxide dismutase (SOD), and the expression of epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) and collagen were detected. RESULTS：On the 21st day after burn, the new epithelial tissues in CSME group extraordinarily　developed  and a great deal of hair also grew along the margin of the wounds. The epithelization rate of the wound tissues in CSME group was higher than that in other groups. There was rare new hair in the center of the wound area in SSD group, but intensive new hair was observed in CSME group. On the 14th day and 21st day after burn, multilayer of epithelial cells was entirely covered with the wound area in CSME group. Some of the healing signs, such as sufficient differentiation and a line up in order of collagen fibers, clear tissue structure, exceedingly active hyperplasia of sebaceous glands and hair follicles, and so on, were also observed in the wound area in CSME group. From the 1st day to 21st day after burn, the increase in protein expression of EGF and bFGF in the wound tissues was significantly higher than that in other groups in the early stage, which was quickly decreased and was obviously lower than other groups in the latter stage. The mRNA expression ratio of type I and III collagens in SSD group was significantly higher than that in other groups, while that in CSME group was significantly lower than that in other groups. CONCLUSION：CSME promotes burn wound healing without scarring. The effects of CSME are likely to associate with the expression reinforcement of EGF and bFGF at mRNA and protein levels in the early stage, and associate with the expression inhibition of them later. Moreover, CSME may also inhibit the mRNA expression of type I collagen and promote the synthesis of type III collagen in the wound tissues of burn.