美洲大蠊温敏凝胶的制备及其促糖尿病大鼠创面修复作用考察

目的:制备美洲大蠊温敏凝胶并考察其促糖尿病大鼠创面修复作用。方法:以N-异丙基丙烯酰胺(NIPAM)与丙烯酸(AAc)为单体,在水相中通过自由基聚合法制得具有温度响应的共聚物P(NIPAM-co-AAc),然后将其接枝透明质酸(HA)以合成P(NIPAM-co-AAc)-g-HA温敏材料,采用核磁共振氢谱(^1H-NMR)和紫外分光光度法(UV)对该材料的化学组成、低临界相转变温度(LCST)进行表征;采用透析法制备美洲大蠊温敏凝胶,利用扫描电子显微镜、旋转流变仪和热重分析仪表征其断面结构、流变学性质和热稳定性;采用差示扫描量热法,X-射线衍射法和傅里叶红外光谱法共同鉴定P(NIPAM-coAAc)-g-HA温敏材料对美洲大蠊提取物的包合作用,并考察美洲大蠊温敏凝胶促糖尿病大鼠创面修复的作用,采用ImagePro Plus 6.0软件计算创面愈合率,运用苏木素-伊红(HE)和Masson染色观察各组大鼠创面组织病理学变化。结果:成功合成了P(NIPAM-co-AAc)-g-HA温敏材料,其LCST处于29~31℃,具有密集、均匀的多孔结构,且能将美洲大蠊提取物均匀包合。药效学结果表明,美洲大蠊温敏凝胶组促创面愈合效果最佳,其炎细胞浸润程度明显降低,胶原蛋白、成纤维细胞排列整齐、致密,新生血管密度较模型组显著增加。结论:美洲大蠊温敏凝胶可有效促进糖尿病大鼠创面愈合,可克服美洲大蠊市面液体制剂用于皮肤创面治疗的不足,可为美洲大蠊提取物促糖尿病患者创面愈合制剂的开发提供参考。

Preparation of Periplaneta americana Thermosensitive Hydrogel and Investigation of Its Wound Healing Effect on Diabetic Rats

Objective:To prepare Periplaneta americana thermosensitive hydrogel and investigate its effect on wound healing in diabetic rats.Method:Taking N-isopropylacrylamide(NIPAM)and acrylic acid(AAc)as monomers,thermosensitive poly(NIPAM-co-AAc)P(NIPAM-co-AAc)]polymeric material was prepared by free radical polymerization,then thermoresponsive copolymer P(NIPAM-co-AAc)-g-HA was synthesized by conjugating P(NIPAM-co-AAc)to hyaluronic acid(HA).The structure and lower critical solution temperature(LCST)of the graft copolymer were characterized by proton nuclear magnetic resonance spectroscopy(^1 H-NMR)and ultraviolet spectrophotometry(UV).P.americana thermosensitive hydrogel was prepared by dialysis method,and it was characterized by scanning electron microscope(SEM),rotation rheometer and thermogravimetric analyzer to observe section structure,rheological properties and thermal stability.Differential scanning calorimetry,X-ray diffraction and Fourier transform infrared spectroscopy were employed to identify the inclusion of P(NIPAM-co-AAc)-g-HA temperature sensitive material for P.americana extract,and to investigate the effect of P.americana thermosensitive hydrogel on wound healing in diabetic rats,and the rate of wound healing was calculated by Image-Pro Plus 6.0 software.Hematoxylin-eosin(HE)and Masson staining were used to observe the pathological changes of the wounds of rats in each group.Result:P(NIPAM-co-AAc)-g-HA temperature sensitive material was successfully synthesized,its LCST was between 29℃and 31℃,it had a dense and uniform porous structure and could uniformly include P.americana extract.Pharmacodynamic studies showed that P.americana thermosensitive hydrogel group had the best effect on promoting wound healing,its infiltration degree of inflammatory cells was significantly reduced,collagen and fibroblasts arranged neatly and compactly,and the density of neovascularization was significantly increased by comparing with the model group.Conclusion:P.americana thermosensitive hydrogel can effectively promote wound healing of diabetic rats and overcome the shortage of marketed P.americana liquid preparations,this paper can provide a reference for the development of P.americana extract preparations to promote wound healing in diabetic patients.