二七方对急性放射性肠损伤大鼠肠道的保护作用及机制

Protective Effect of Erqi Decoction on Intestinal Tract of Acute Radiation Intestinal Injury Rats and Its Mechanism

【目的】探讨二七方(由朱砂七、蜈蚣七、秦皮、黄柏、大黄等组成)对急性放射性肠损伤大鼠肠道的保护作用及机制。【方法】将60只健康清洁级成年SD大鼠随机分为正常组、模型组、白头翁汤组和二七方组,每组15只。采用6 MV高能X线10 Gy全腹部照射,复制急性放射性肠炎大鼠模型。二七方组、白头翁汤组分别给予相应药物二七方(剂量为8.85 g·kg^(-1)·d^(-1))、白头翁汤(剂量为4.69 g·kg^(-1)·d^(-1))灌胃治疗,正常组、模型组给予等体积生理盐水灌胃,连续7 d。造模结束后,取回盲部近端回肠,光镜下观察回肠组织病理学,采用图像分析仪测定绒毛高度、隐窝深度、黏膜和全层厚度,采用分光光度计测定回肠组织中MPO含量,采用免疫组化法测定回肠组织中caspase-3和PCNA的表达水平。【结果】二七方组和白头翁汤组回肠结构损伤较轻,绒毛高度、隐窝深度、黏膜厚度和全层厚度均显著大于模型组(P<0.05),但2个给药组差异无统计学意义(P>0.05);二七方组和白头翁汤组MPO含量较模型组显著降低(P<0.05),且二七方组MPO含量显著低于白头翁汤组(P<0.05);二七方组与白头翁汤组caspase-3、PCNA表达水平较模型组显著升高(P﹤0.05),但2组差异无统计学意义(P>0.05)。【结论】二七方对急性放射性肠炎大鼠肠黏膜及组织损伤具有修复作用,其机理可能通过减轻局部炎症反应,促进肠黏膜上皮增殖,抑制上皮细胞凋亡而实现。

Objective To investigate the protective effects of Erqi Decoction（EQD; mainly composed of Radix Aristolochiae Kaempferi, Radix Rhizoma Seu Flos Cypripedii, Cortex Fraxini, Cortex Phellodendri, Radix et Rhizoma Rhei） on the intestinal tract in rats with acute radiation intestinal injury and its mechanism. Methods Sixty SD rats were randomly divided into normal group, model group, EQD group and Baitouweng Decoction group （BD group）, 15 rats in each group. The acute radiation enteritis model was established by exposing the whole abdomen to a total dose of 10 Gy of 6 MV higher-energy X-rays. EQD group and BD group were given intragastrical administration with corresponding medicine of EQD at the dose of 8.85 g·kg^-1·d^-1, BD at the dose of 4.69 g·kg-1·d-1 respectively, and the normal group and the model group were given intragastrical administration with the same volume of normal saline. The treatment lasted for 7 continuous days. After modeling, the morphological change of the proximal ileum tissue was observed under light microscope. Villus height, crypt depth, and thickness of the ileal mucosa and entire wall were measured by image analysis system. The myeloperoxidase （MPO） content in ileum tissue was determined by spectrophotometer, and the expression levels of caspase -3 and proliferating cell nuclear antigen （PCNA） in ileum tissue were determined by immunohistochemistry. Results EQD group and BD group had milder injuries of the ileal structure, and had higher villus height, crypt depth, and thickness of mucosa and entire wall than those in the model group （P 〈0.05）, but there were no differences between the two medication groups（P 〉 0.05）. MPO content in EQD group and BD group was decreased（P〈0.05 compared with that in the model group）, and MPO content in EQD group was lower than that in BD group. The expression levels of caspase-3 and PCNA were increased in EQD group and BD group（P 〈 0.05 compared with those in the model group）, but there were no statistical differences between the two medication groups （P〉0.05）. Conclusion EQD has certain protective effects against radiation-induced intestinal damage, which mechanism is probably associated with relieving the local intestinal inflammatory reaction, accelerating intestinal epithelial cell proliferation, and inhibiting intestinal epithelial cell apoptosis.