穿心莲内酯对脓毒症小鼠的保护作用及机制探讨

Protective effects of andrographolide on septic mice and the related mechanism

目的研究穿心莲内酯对脓毒症小鼠的保护作用及相关机制。方法采用盲肠结扎穿孔(CLP)法制作小鼠脓毒症模型。64只C57BL/6小鼠随机均分为4组:假手术组(sham组)、脓毒症模型组(CLP组)、二甲亚砜组(DMSO组)和穿心莲内酯组(AND组)。各组小鼠于术后1、6、12h腹腔内分别注射相同剂量(0.2mL)的生理盐水、5%DMSO或穿心莲内酯(10mg/kg),记录各组小鼠术后7d生存率并绘制生存曲线。另取48只C57BL/6小鼠,分组及给药方法同前,术后24h分别检测腹腔灌洗液(PLF)中性粒细胞(PMN)数量、外周血及PLF细菌负荷以及外周血炎症因子TNF-α、IL-6、IL-10水平,同时取小鼠肺脏及肝脏组织进行病理分析。结果与CLP组相比,AND组小鼠术后7d生存率增加(P<0.01),腹腔PMN计数下降(P<0.01),外周血和腹腔细菌清除能力增强(P<0.01),外周血TNF-α、IL-6水平降低,而IL-10水平升高(P<0.01),肺组织和肝脏组织病理损伤程度减轻(P<0.01)。DMSO组与CLP组各项检测指标差异均无统计学意义。结论穿心莲内酯对CLP脓毒症小鼠具有保护作用,可能与其调节免疫功能,增强细菌清除能力以及降低过度炎症反应有关。

Objective To investigate the protective effects of andrographolide on septic mice and to explore the underlying mechanism. Methods Sepsis model was induced by cecal ligation and puncture （CLP） in mice. A total of 64 C57BL/6 mice were evenly randomized into 4 groups., a sham group, a CLP group, a dimethyl sulfoxide （DMSO） group and an andrographolide （AND） group. The mice were injected intraperitoneally with 0.2 mL normal saline, 0.2 mL 5% DMSO or 0.2 mL andrographolide （10 mg/kg） at 1 h, 6 h and 12 h after surgery. The survival rates were assessed 7 days after surgery and the survival curve was plotted. Another 48 C57BL/6 mice were grouped as above. The peripheral blood, peritoneal lavage fluid （PLF）, lung and liver tissues were harvested 24 h after operation. Polymorphonuelear leukocyte （PMN） count in PLF was determined. Bacterial loads in the peripheral blood sample and PLF were also determined. The levels of TNF-a, IL-6 and IL-10 in the blood samples were detected by ELISA. The lung and liver tissues were observed and analyzed by hematoxylin-eosin staining. Results Compared with CLP group, AND group had a significantly increased survival rate 7 days after operation （P〈0.01）, a significantly decreased PMN count in PLF （P〈0. 01）, a significantly enhanced bacterial clearance capability in both blood and PLF （P〈0.01）, significantly decreased serum TNF-a and IL-6 levels, significantly increased IL-10 level, and significantly alleviated lung and liver tissue injuries （P〈0.01）. The above parameters were not significantly different between the DMSO group and CLP group. Conelusion Andrographolide has protective effect against CLP-induced sepsis in mice, which might be associated with regulation of the immunological function, enhancement of bacterial clearance and inhibition of excessive inflammatory response during sensis.