大麻素2型受体激动剂JWH-015对阿尔茨海默病样小鼠认知功能的改善作用及其可能机制  

Ameliorative effect of cannabinoid 2 receptor agonist JWH-015 on cognitive impairment of Alzheimer′s disease model mice and its possible mechanism

作　　者：李超[1] 史敬璞 王立宽[1,2] 贾慧群[1] 王勃[2] 李锦[2] LI Chao SHI Jing-pu WANG Li-kuan JIA Hui-qun WANG Bo LI Jin(Department of Anesthesiology, the Fourth Hospital of Hebei Medical University, Shifiazhuang 050017, China Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing 100850, China)

机构地区：[1]河北医科大学第四医院麻醉科,石家庄050017 [2]军事医学科学院毒物药物研究所,北京100850

出　　处：《国际药学研究杂志》2017年第6期537-543,共7页Journal of International Pharmaceutical Research

基　　金：国家自然科学基金资助项目(81471233);北京市科委科技新星资助项目(Z121102002512046);河北省自然科学基金资助项目(H201406282)

摘　　要：目的观察大麻素2型受体(CB2R)激动剂JWH-015对阿尔茨海默病(AD)小鼠认知功能下降的改善作用,并探讨其作用机制是否与脑内小胶质细胞激活表型转化密切相关。方法 20只成年雄性C57BL/6J小鼠随机分为溶剂对照组、JWH-015对照组、AD模型组和JWH-015治疗组。侧脑室注射4μg寡聚态β-淀粉样蛋白1-42(Aβ1-42)和等体积生理盐水构建AD模型和模型对照组后,分别接受连续3周腹腔注射JWH-015 0.5 mg/kg或等量溶剂处理。采用新物体识别实验检测小鼠认知功能;实时定量PCR方法检测皮质、海马脑区M1型小胶质细胞标记分子诱导型一氧化氮合酶(i NOS)和M2型小胶质细胞标志物几丁质酶3样蛋白(Ym1/2)m RNA表达水平。同时,取15只CB2R基因敲除C57BL/6J小鼠(CB2RKO)和5只同窝野生型(CB2RWT)小鼠按基因型和处理随机分为CB2RKO溶剂对照组、CB2RKO AD模型组、JWH-015处理组和CB2RWT小鼠溶剂对照组,用来研究CB2R对认知功能改善作用和小胶质细胞激活表型转化作用的特异性。结果与溶剂对照组相比,C57BL/6J AD模型组小鼠新奇物体识别指数显著降低(P<0.01),同时伴随皮质和海马脑区i NOS m RNA表达显著升高(均为P<0.05)和Ym1/2 m RNA表达显著降低(均为P<0.01);而JWH-015处理可显著提高C57BL/6J AD模型组小鼠新物体识别指数(P<0.05),下调皮质和海马区i NOS m RNA表达水平(均为P<0.05),上调Ym1/2 m RNA表达水平(均为P<0.05);与脑室注射生理盐水的CB2RKO溶剂对照组小鼠相比,CB2RKO AD模型组小鼠识别指数显著降低(P<0.05),皮质和海马脑区i NOS m RNA表达显著升高(均为P<0.05),皮质脑区Ym1/2 m RNA表达显著降低(P<0.05);与CB2RKO AD模型组小鼠相比,JWH-015处理组长时程给药对新奇物体识别指数无显著影响,并对皮质、海马脑区内i NOS及Ym1/2 m RNA的表达水平无显著影响。结论 JWH-015通过特异性激动CB2R改善Aβ诱导的AD模型小鼠的认知能力下降,其机制可能与其直接作�Objectives To investigate the ameliorative effect of cannabinoid 2 receptor（CB2R）agonist JWH-015 on the cognitive impairment of Alzheimer′s disease（AD）model mice and to assess the correlation with microglial phenotype transformation.Methods Twenty adult male C57BL/6J mice were randomly divided into four groups：C57BL/6J solvent group,JWH-015 control group,AD model group,and AD model treated with JWH-015 group. Amyloid β1-42 oligomers of 4 μg and the same volume of saline were intraventricularly administered to construct the AD mouse model and the solvent groups. CB2 R agonist JWH-015 or the corresponding vehicle at a dose of 0.5 mg/（kg·d）was administered by intraperitoneal injection for 3 weeks. Non-spatial learning and memory was measured using novel object recognition task. Furthermore,the m RNA expression levels of M1 microglia marker inducible nitric oxide synthase（i NOS）and M2 microglia marker chitinase-3 like protein（Ym1/2）in brain samples of cortex and hippocampus were evaluated using real-time quantitative PCR（q PCR）. In the meantime,fifteen CB2 R knockout（CB2RKO）mice and five CB2 R wild-type（CB2RWT）littermates were assigned to identify the specificity of CB2 R in the research. Based on the genotype and different treatment,the animals were divided into four groups：CB2RKO solvent group,CB2 RKO AD model group,CB2 RKO AD model treated with JWH-015 group and CB2 RWT solvent group. Results Compared with solvent group,there was a significant decrease in novel object recognition index in C57BL/6J AD model group（P0.01）. The m RNA expression levels of M1 phenotype microglia marker i NOS in cortex and hippocampus were significantly up-regulated（both P0.05）and the m RNA expression levels of M2 phenotype microglia marker Ym1/2 were significantly down-regulated（both P0.01）. Interestingly,administration of JWH-015 could reverse the impairment of novel object recognition index（P0.05）;compared with C57BL/6J AD model group,administration of JWH-015 also decreased the

关 键 词：阿尔茨海默病 大麻素2型受体 小胶质细胞激活表型 认知功能 

分 类 号：R285.5[医药卫生—中药学]