头孢曲松通过抑制Cx43磷酸化参与治疗创伤性颅脑损伤的机制

目的观察头孢曲松(CFX)通过调控与缝隙连接蛋白43(Cx43)表达在治疗创伤性颅脑损伤(TBI)的相关性机制。方法选取100只体重350～450g的4月龄的SD雄性大鼠,采用液压打击仪建立脑损伤模型,具体分组为:①假手术(sham)组、②治疗(TBI+CFX)治疗组、③甘珀酸(CBX)阻断(TBI+CFX+CBX)组、④溶媒(TBI+生理盐水)组及⑤损伤(TBI)组,每组20只。实验时间均设定为TBI后48 h。每组取10只大鼠进行行为学检测和脑组织含水量测定,另10只则获取海马区胶质组织通过蛋白免疫印记法(WB)法测定神经元缝隙连接蛋白40(Cx40)及磷酸化Cx43蛋白(p-Cx43)的变化、采用酶联免疫荧光(ELFA)检测神经元氧化应激因子NADPH氧化酶活性的变化。结果实验结果显示,采用CFX干预组神经损伤严重度评分(NSS)、脑水肿程度、腺嘌呤二核苷酸磷酸(NADPH)氧化酶活性及海马胶质细胞Cx40、p-Cx43表达均溶媒组及损伤组明显下降(P 0.05)。而CBX可明显抑制上述CFX对Cx40、p-Cx43蛋白表达下调及降低NADPH氧化酶的活性的作用(P0.05)。结论 CFX可能通过抑制Cx43蛋白磷酸化和Cx40蛋白异常增多,从而抑制氧化应激反应以达到脑损伤缓解作用。

MECHANISM OF CEFTRIAXONE BY INHIBITING THE PHOSPHORYLATION OF Cx43 IN THE TREATMENT OF TRAUMATIC BRAIN INJURY

Objective: To investigate the mechanism of protective effects of Ceftriaxone (CFX) against traumatic brain injury. Methods: Traumatic brain injury model were established by Sprague-Dawley rats at the age of 4 months with fluid percussion device and given intraperitoneal injection of Ceftriaxone and Cx43 inhibitor Cerbenoxolone (CBX). CBX was substituted by Normal Saline (NS) in Vehicle group, and injury group was not given any intervention after TBI. 100 rats were randomly divided into 5 groups:Sham operation, Treatment group (TBI+CFX), Inhibitor group (TBI+CFX+CBX), Vehicle group (TBI+ NS) and Injury group (TBI). Half rats in each group were tested for behavioral disorder by NSS and brain edema by measuring brain water content at 48 hours after TBI, and another half of rats were sacrificed and hippocampal astorcytes were obtained for investigating p-Cx43, Cx40 by western blot, NDAPH oxidase activity by ELFA. Results: NSS, brain water content, p-Cx43, Cx40 and NDAPH oxidase activity in treatment group were significantly lower than those in veichle and injury group, and the protective effects induced by CFX could be alleviated by CBX. Conclusion: Protective effect of CFX to TBI is involved in inhibiting the phosphorylation of Cx43, which can reduce the oxidative stress, injuries of form and function of brain after TBI.