Wnt1-Ngn2-En1/2在西玛津损伤小鼠生命早期多巴胺能神经元功能中的作用  

The role of Wnt1-Ngn2-En1/2 in the simazine-induced injury to the dopaminergic neurons in early life of mice

作　　者：刘茄琦 闻杰 张佳钰 李百祥 李雪婷 LIU Jiaqi;WEN Jie;ZHANG Jiayu;LI Baixiang;LI Xueting(Department of Health Toxicology,College of Public Health,Harbin Medical University,Harbin 150081,Heilongjiang,China)

机构地区：[1]哈尔滨医科大学公共卫生学院卫生毒理学教研室,黑龙江哈尔滨150081

出　　处：《癌变．畸变．突变》2024年第6期444-451,共8页Carcinogenesis,Teratogenesis & Mutagenesis

基　　金：黑龙江省省属高等学校基本科研业务费科研项目(31041200006);国家自然科学基金项目(82204079)。

摘　　要：目的:观察除草剂西玛津对小鼠子代胚胎期及出生后第21天(PND21)多巴胺能神经元发育的影响,并探讨Wnt1-Ngn2-En1/2信号通路在神经元损伤中的作用。方法:健康SPF级昆明小鼠雌性30只,雄性15只,按照2∶1进行合笼。将孕鼠随机分为对照组(0.3%甲基纤维素溶液)和西玛津低剂量(50μg/kg)、高剂量组(200μg/kg)进行灌胃染毒,收集胚胎第8.5天(E8.5)、第12.5天(E12.5)和PND21仔鼠的中脑组织,采用免疫荧光杂交技术(FISH)、实时荧光定量PCR(qPCR)和Western blot分别检测Wnt1-Ngn2-En1/2信号通路相关基因(Wnt1、Ngn2、En1、En2、Nr4a2与Th)mRNA和蛋白的表达;通过旷场实验检测孕鼠染毒西玛津后对PND21雌、雄仔鼠自主行为能力的影响。结果:qPCR与Western blot检测结果显示,与对照组相比,在E8.5胚胎组织中,西玛津低剂量染毒组Wnt1和Ngn2以及高剂量组Wnt1、Ngn2、En1和En2的m RNA与蛋白表达均明显下降(P<0.05);在E12.5胚胎组织中,低剂量染毒组Nr4a2和Th以及高剂量组Nr4a2、Th、Wnt1、Ngn2、En1、En2的mRNA和蛋白表达均显著下降(P<0.05)。FISH检测结果显示,与对照组相比,西玛津低、高剂量染毒组E8.5与E12.5胚胎组织中Wnt1的mRNA表达均明显下降(P<0.05);西玛津高剂量组PND21雄性仔鼠的自主探索能力与运动能力显著减弱(P<0.05),且PND21仔鼠组织中Wnt1与Th的蛋白表达也明显下调(P<0.05)。结论:西玛津能够通过Wnt1-Ngn2-En1/2信号通路影响子代小鼠多巴胺能神经元发育,并损伤雄性仔鼠的自主行为能力。OBJECTIVE:To investigate the role of the Wnt1-Ngn2-En1/2 signaling pathway in the herbicide simazine-induced damage to the dopaminergic neurons in embryonic and weaned mice.METHODS:Fifteen female and fifteen male healthy SPF Kunming mice were kept in containers in a 2∶1 ratio.During pregnancy,three groups of maternal mice were randomized∶control group(0.3%methyl cellulose solution),low-dose group(50μg/kg)and high-dose group(200μg/kg).The tissues of the offspring on the day 8.5(E8.5),day 12.5(E12.5),and postnatal day 21(PND21)of development were obtained.mRNA and protein expression of the Wnt1-Ngn2-En1/2 signaling pathway-related genes(Wnt1,Ngn2,En1,En2,Nr4a2 and Th)were detected using immunofluorescence hybridization(FISH),real-time fluorescence quantitative PCR(qPCR)and Western blot.Through an open field experiment,effect of the treated pregnant mice on the autonomic behavior of PND21 female and male mice were identified.RESULTS:Western blot and qPCR data in E8.5 demonstrated that in comparison to the control group,low simazine-exposed groups had a decrease in the mRNA and protein expression of Wnt1 and Ngn2(P<0.05),and the high-dose group had a substantial decline in the expressions of Wnt1,Ngn2,En1 and En2(P<0.05).The results of E12.5 embryo show the mRNA and protein expression of Nr4a2 and Th in the low-dose group declined as compared with the control group,(P<0.05),and the expression of Nr4a2,Th,Wnt1,Ngn2,En1 and En2 in high-dose group decreased significantly compared with that in control group(P<0.05).The FISH data verified that Wnt1 mRNA expression was substantially reduced in the low-dose and high-dose sections of E8.5 and E12.5 as opposed to that of the control group(P<0.05).The high-dose group of PND21 offspring exhibited significantly reduced motor and self-exploration abilities in comparison to the male offspring of the control group(P<0.05),and there was a notable down-regulation of Wnt1 and Th protein expressions(P<0.05).CONCLUSION:Simazine affected the development of dopaminergic neurons in m

关 键 词：西玛津 生命早期 神经毒性 多巴胺能神经元 

分 类 号：R994.6[医药卫生—毒理学]