经鼻胰岛素对高原小鼠记忆损伤的保护作用  

Protective effect of intranasal insulin on memory impairment in mice exposed to high altitude

作　　者：陈思雨 冷玉洁 张明 林露 袁利邦 巩固 CHEN Siyu;LENG Yujie;ZHANG Ming;LIN Lu;YUAN Libang;GONG Gu(School of Clinical Medical Sciences,Southwest Medical University,Luzhou 646000,China;Department of Anesthesiology,General Hospital of Western Theater Command,Chengdu 610083,China;Basic Medical Laboratory,General Hospital of Western Theater Command,Chengdu 610083,China)

机构地区：[1]西南医科大学临床医学院,四川泸州646000 [2]解放军西部战区总医院麻醉科,四川成都610083 [3]解放军西部战区总医院基础医学实验室,四川成都610083

出　　处：《空军军医大学学报》2023年第11期1070-1075,共6页Journal of Air Force Medical University

基　　金：军队后勤应用基础研究项目(CLB19J051)。

摘　　要：目的探索经鼻给药胰岛素对高原小鼠记忆损伤的防治作用及机制。方法将80只雌性C57BL/6小鼠随机分为常氧对照(CON)组、高原(HH)组、生理盐水(NS+HH)组、胰岛素预处理(I+HH)组和胰岛素治疗(HH+I)组,每组16只。NS+HH组和I+HH组连续经鼻给生理盐水或胰岛素17.5μL(即胰岛素1.75 U)7 d后和HH组、HH+I组放入低压氧舱,模拟海拔6000 m,放舱7 d。期间HH+I组每日出舱行经鼻胰岛素给药1.75 U。通过Morris水迷宫实验测试小鼠的认知功能;通过过氧化氢(H 2 O 2)测试盒、丙二醛(MDA)测试盒、超氧化物歧化酶(SOD)测试盒、Western blotting实验、尼氏染色观察海马氧化应激、神经元凋亡和神经突触功能改变的情况。结果①与CON组相比,HH组(P<0.01)小鼠出现明显的记忆损伤,HH+I组高原小鼠记忆显著改善(P<0.01);②与CON组相比,HH组海马区氧化应激指标H 2 O 2(P<0.05)、MDA(P<0.05)升高,抗氧化指标SOD活性呈降低趋势;I+HH组和HH+I组氧化应激指标被逆转;③尼氏染色显示,HH组CA1区神经元尼氏小体溶解明显,I+HH组和HH+I组此现象明显减轻;HH组CA3区出现大量核固缩深染细胞,I+HH组和HH+I组核固缩细胞显著减少;④与CON组相比,HH组B淋巴细胞瘤2蛋白表达量显著降低(P<0.01),cleaved caspase-3表达量显著升高(P<0.01);I+HH组和HH+I组逆转凋亡相关蛋白表达;⑤与CON组相比,HH组(P<0.05)突触蛋白1(Syn-1)表达水平下降,I+HH组(P<0.01)和HH+I组(P<0.05)Syn-1表达量显著升高。结论经鼻胰岛素可通过减轻海马氧化应激损伤、减少神经元凋亡、提高突触功能,防治高原环境诱导的记忆损伤。Objective To explore the protective effect and mechanism of intranasal administration of insulin on memory impairment in mice exposed to high altitude.Methods Eighty female C57BL/6 mice were randomly divided into normoxic control(CON)group,high altitude(HH)group,normal saline(NS+HH)group,insulin pretreatment(I+HH)group and insulin therapy(HH+I)group,with 16 mice in each group.After 7 d of continuous nasal feeding of normal saline or insulin 17.5μL(i.e.,insulin 1.75 U)in NS+HH group and I+HH group,they were placed in a hypobaric oxygen chamber with HH group and HH+I group at a simulated altitude of 6000 m for 7 d.During this period,HH+I group was administered 1.75 U of intranasal insulin every day.The cognitive function of mice was tested by Morris water maze experiment.Oxidative stress,neuronal apoptosis,and changes in synaptic function in hippocampus were observed by hydrogen peroxide(H 2 O 2)test kit,malondialdehyde(MDA)test kit,superoxide dismutase(SOD)test kit,Western blotting,and Nissl staining.Results①Compared with CON group,mice in HH group(P<0.01)showed obvious memory impairment,and mice in HH+I group significantly improved memory(P<0.01);②Compared with CON group,oxidative stress indexes H 2 O 2(P<0.05)and MDA(P<0.05)of hippocampal region in HH group increased,and the antioxidant index SOD showed a decreasing trend.The oxidative stress indexes were reversed in I+HH group and HH+I group;③Nissl staining showed that the dissolution of Nissl bodies of neurons in CA1 region was obvious in HH group,and this phenomenon was significantly reduced in I+HH group and HH+I group.A large number of nuclear pyknotic hyperchromatic cells appeared in CA3 region of HH group,and the number of nuclear pyknotic hyperchromatic cells in I+HH group and HH+I group decreased significantly;④Compared with CON group,the expression of B-cell lymphoma-2 in HH group was significantly reduced(P<0.01),and the expression of cleaved caspase-3 was significantly increased(P<0.01).The expression of apoptosis-associated proteins was rev

关 键 词：高原低氧 胰岛素 经鼻给药 学习记忆 氧化应激 凋亡 突触蛋白1 

分 类 号：R339.5[医药卫生—人体生理学]