大黄调控肠道水通道蛋白对脓毒症大鼠肠道菌群的影响

目的:探究大黄治疗脓毒症模型大鼠的病原生物学机制。方法:采用LPS腹腔注射法制作大鼠脓毒症模型,实验分为5组,分别为假手术组,脓毒症模型组,大黄高、中、低剂量组(150,100,50 mg·kg^-1),2次/d ig给药,连续给药3 d,记录各组大鼠病死率情况,采用细菌传统培养法对大鼠膜菌群、腔菌群及肠系膜淋巴结、血液进行细菌培养计数,同时通过RT-qPCR及Western blot法检测大鼠结肠水通道蛋白水通道蛋白2(AQP2)和AQP8。结果:大黄高、中剂量组大鼠病死率降低;各组大鼠膜菌群和腔菌群变化差异大,以大肠杆菌、金黄色葡萄球菌、乳酸杆菌及双歧杆菌较明显,各治疗组AQP2和AQP8表达与脓毒症模型组有明显差异性(P<0.05)。且各治疗组AQP2和AQP8表达下降,与大黄剂量有依赖性,同时淋巴结与血标本细菌含量有所降低。结论:大黄可下调AQPs表达发挥泻下功能,减少脓毒症大鼠细菌移位治疗脓毒症,但中剂量大黄在发挥上述作用时有利用平衡肠道菌群。

Effects of Rhei Radix et Rhizoma on Intastinal Flora of Septic Rats by Regulating Aquaporins Expression

Objective: To investigate the mechanism of Rhei Radix et Rhizoma on intestinal flora of septic rats. Method: LPS intraperitoneal injections were used to establish septic rats models. The rats in the experiment were divided into five groups:sham operation group, septic model group, Rhei Radix et Rhizoma high dose, middle dose and low dose groups (150, 100, 50 mg·kg^-1), 2 times/d ig, continuous for 3 days. The mortality of each group was recorded. Traditional bacterial culture method was used to detect bacteria count of membrane flora, cavity flora, mesenteric lymph nodes and blood of the rats. Meanwhile aquaporin 2(AQP2) and AQP8 were detected by RT-qPCR and Western blot. Result: The mortality in Rhei Radix et Rhizoma high dose group and middle dose group was significantly decreased. Membrane flora and cavity flora of all groups differ greatly, especially Escherichia coli, Staphylococcus aureus, Lactobacill and Bifidobacterium. AQP2 and AQP8 expression levels of all treated groups differed greatly from those of model group(P<0.05). The decrease in AQP2 and AQP8 expression levels in various treatment groups was dependent on the dose of Rhei Radix et Rhizoma. meanwhile, the number of pathogens in lymph nodes and blood was lower than that of model group. Conclusion: Rhei Radix et Rhizoma can decrease bacterial translocation by reducing expression of AQPs to increase excreta in treating sepsis, and the middle dose is better for the balance of intestinal flora.