摘要
目的:探讨微小RNA‐9‐5p(miR‐9‐5p)、Ras同源基因家族成员A(RHOA)在铝致大鼠认知功能障碍中的可能机制。方法:根据随机分组的原则,把48只Wistar大鼠随机分为对照、低剂量、中剂量、高剂量4个组(n=12)。空白对照组每日灌胃生理盐水,其余组以25 mg/kg、50 mg/kg和100 mg/kg 3个剂量每天灌胃AlCl3水溶液来创建认知障碍大鼠模型,周期3个月。采用水迷宫(MWM)定位航行实验记录大鼠上平台的时间t(s),即潜伏期,根据各组大鼠的潜伏期来判断染毒组大鼠是否存在学习记忆能力障碍;苏木精‐伊红(HE)、尼氏(Nissl)染色观察4个组的海马区的神经细胞病理变化;蛋白免疫印迹法(Western Blot)检测新鲜大鼠海马组织中RHOA、脑神经性营养因子(BDNF)的蛋白表达水平;实时荧光定量聚合酶链式反应(RT‐qPCR)检测大鼠海马组织中miR‐9‐5p、RHOA、BDNF的mRNA表达量。结果:Morris水迷宫定位航行试验结果表明,在实验第1、3、5天计算各个组的潜伏期,与对照组相比,染毒组运动潜伏期均高于对照组。HE染色结果显示,对照组大鼠神经细胞形态完整,染色清晰,细胞核清晰可见,胞膜边缘锐利。染毒组大鼠神经元受到不同程度的损伤,细胞核逐渐溶解,细胞质染色变深,细胞膜边缘模糊紊乱,细胞变形,排列紊乱。尼氏染色结果显示,对照组大鼠神经细胞内可见染色清晰的Nissl体颗粒,染毒组神经细胞内Nissl体消散减少,染色较浅。RT‐qPCR结果显示,与对照组相比,染毒组miR‐9‐5p、BDNF的mRNA表达均下降,RHOA的mRNA表达升高(P<0.05或P<0.001)。Western Blot结果显示,与对照组相比,染毒组BDNF的蛋白相对表达量均下降,RHOA的蛋白相对表达量升高(P<0.05)。结论:在铝致大鼠认知障碍中,大鼠海马组织miR‐9‐5p下调,RHOA上调。
Objective:To investigate the possible mechanism of microRNA‐9‐5p(miR‐9‐5p)and Ras homologous gene family A(RHOA)in aluminum‐induced cognitive dysfunction in rats.Methods:According to the principle of randomization,48 Wistar rats were randomly divided into four groups(n=12)of blank control,low dose,medium dose and high dose.The blank control group was gavaged daily saline,and the other three dose groups were given daily gavage AlCl3 aqueous solution at three doses of 25 mg/kg,50 mg/kg,and 100 mg/kg to create a rat model of cognitive impairment for three months.The water maze(MWM)positioning navigation experiment was used to record the time t(s),namely,the incubation period,on the platform of rats,and the incubation period of each group was used to determine whether the rats in the infected group had learning and memory impairment.Hematoxylin‐eosin(HE)and Nissl stains observed the pathological changes of nerve cells in the hippocampus of the four groups.Western blot detected the protein expression levels of RHOA and cranial neurotrophic factor(BDNF)in fresh rat hip‐pocampal tissues.RT‐qPCR detected the mRNA expression of miR‐9‐5p,RHOA,and BDNF in rat hippocampal tissues.Re⁃sults:The results of Morris water maze positioning navigation test showed that the incubation period of each group was calculated on the 1st,3rd and 5th days of the experiment,and the motor incubation period of the infected group was higher than that of the control group.The results of HE staining showed that the rat nerve cells in the control group were morphologically intact,the staining was clear,the nucleus was clearly visible,and the edge of the cell membrane was sharp.The rat neurons in the infected group were damaged to varying degrees,the nucleus gradually dissolved,the cytoplasmic staining became deeper,the edges of the cell membrane were blurred and disordered,and the cells were deformed and arranged disordered.The results of Nissl staining showed that the well‐stained Nissl body particles were visible in the nerve cells of rats in the control group,and the dissipation of Nissl bodies in the nerve cells of the infected group was reduced,and the staining was shallow.The results of RT‐qPCR showed that compared with the control group,the mRNA expression of miR‐9‐5p and BDNF was decreased in the infected group,and the mRNA expression of RHOA was increased(P<0.05 or P<0.001).The Western blot results showed that compared with the con‐trol group,the relative expression of BDNF in the three infected groups was decreased,and the relative expression of RHOA in‐creased(P<0.05).Conclusion:In aluminum‐induced cognitive impairment,miR‐9‐5p is downregulated and RHOA is upregu‐latd.
作者
贾芸菁
钟斌
李晨羽
甘珏方
廉春容
李莎莎
凌雁武
JIA Yun‐jing;ZHONG Bin;LI Chen‐yu;GAN Jue‐fang;LIAN Chun‐rong;LI Sha‐sha;LING Yan‐wu(Youjiang Medical College for Nationalities,Baise 533000,China)
出处
《海南医学院学报》
2023年第14期1063-1068,共6页
Journal of Hainan Medical University
基金
国家自然科学基金项目(31560294)
2021年广西学位与研究生教育改革课题(JGY2021208)。
