氯碘羟喹对铅暴露致大鼠海马铜相关蛋白损伤的修复作用研究

目的探讨氯碘羟喹(CQ)对铅暴露大鼠脑组织中铜相关蛋白变化的影响,为铅中毒的修复提供理论依据。方法50只雄性SD大鼠随机分为对照组、CQ组、铅暴露组、铅+CQ组及铅+CQ+VB_(12)组,每组10只。对照组和CQ组大鼠饮用0.03%乙酸钠饮水,其余3组大鼠饮用0.03%乙酸铅饮水,共9周;之后CQ组、铅+CQ组和铅+CQ+VB_(12)组大鼠腹腔注射CQ(30 mg/kg)1周。用Morris水迷宫实验检测大鼠神经行为变化,采用电感耦合等离子体质谱法测定海马中铅和铜水平,用ELISA方法检测铜相关蛋白表达,以HE染色观察海马的病理改变。结果与对照组比较,铅暴露组大鼠第3天的定位航行时间延长,穿台次数减少;海马中铅和铜含量增加,铜锌超氧化物歧化酶(Cu/Zn SOD)和铜蓝蛋白(CP)活力下降,铜伴侣蛋白(CCS、ATOX1、COX17)表达下降,差异均有统计学意义(P0.05);铅暴露大鼠海马的神经元细胞深染,细胞质凝胶。与铅暴露组比较,铅+CQ组大鼠第3天的定位航行时间、穿台次数无明显变化(P0.05);大鼠海马中铅含量下降,差异有统计学意义(P0.05),而铜含量无明显变化(P0.05)。与铅暴露组比较,铅+CQ+VB_(12)组大鼠第3天的定位航行时间明显缩短,穿台次数增加,差异有统计学意义(P0.05);海马中铅和铜含量分别比铅暴露组下降55.94%和11.29%,差异有统计学意义(P0.05)。铅+CQ组和铅+CQ+VB_(12)组大鼠海马中CP活力均高于铅暴露组,铅+CQ+VB_(12)组CCS蛋白表达水平高于铅暴露组,差异均有统计学意义(P0.05)。HE染色表明,CQ注射后铅暴露组大鼠海马中深染细胞减少。结论 CQ能够改善大鼠认知功能,这可能与改变某些铜相关蛋白的表达有关,提示CQ可用于修复铅中毒导致的神经损伤。

Effect of clioquinol on copper-related proteins alternation in hippocampus of rats exposed to lead

Objective To investigate the effect of cliquinol on copper-related proteins alteration of rats with lead exposure in order to provide the basis for repair study of lead neurotoxicity.Methods Fifty SD male rats were randomly divided into control group,clioquinol group,lead exposure group,lead exposure+clioquinol group and lead exposure+clioquinol+vitamin B12 group,10 in each group.The rats in control group and CQ group were given 0.03％ sodium acetate through drinking water.The rats in other three groups were given 0.03％ lead acetate through drinking water for nine consecutive weeks.Then clioquinol group,lead exposure +clioquinol group and lead exposure +clioquinol +vitamin B12 group rats were abdominally injected choquinol for one week.Morris water maze test was used to measure the changes of neural behavior.The lead and copper contents were determined by ICP-MS.ELISA was used to detect the changes of copper-related proteins.HE staining was used to observe the pathological changes in the hippocampus.Results Compared with the control group,the navigation time of rats in lead exposure group extended and times of crossing platform reduced.The lead and copper contents were both increased in hippocampus of lead acetate exposed rats,the difference was statistically significant (P＜0.05).In addition,the activities of CP and Cu/Zn SOD of hippocampus in lead exposure group were lower than those of control group (P＜0.05).Compared with the control group,the levels of CCS,ATOX1 and COX17 decreased in hippocampus of lead exposure rats (P＜0.05).The neurons in hippocampus of lead exposure rats were stained deeper and the cytoplasm was condensed.There was no significant difference between lead group and lead+clioquinol group in terms of navigation time and crossing platform times.Compared with the lead exposure group,the navigation time of rats in lead exposure +clioquinol +vitamin B12 group was shorter and times of crossing platform increased,the differences were statistically significant (P＜0.05).Besides that,the content of lead and copper of hippocampal tissue in lead exposure+clioquinol+vitamin B12 group decreased by 55.94％ and 11.29％ respectively (P＜0.05).The lead content of hippocampal tissue in lead exposure+clioquinol group decreased (P＜0.05).The activity of CP in lead exposure+ clioquinol group and lead exposure+clioquinol+vitamin B12 group were all higher than that in lead exposure group.At the same time,the CCS content in lead exposure+clioquinol+vitamin B12 group increased (P＜0.05).Meanwhile the number of deep stained neuron was reduced after the treatment with clioquinol.Conclusion Clioquinol may improve the cognitive function through changing some copper-related proteins' expression,and clioquinol may be the candidate therapy drug for lead poisoning.