邻苯二甲酸二丁酯诱导小鼠神经行为学改变及相关生理生化指标分析

探究邻苯二甲酸二丁酯诱导小鼠神经行为学改变及与细胞外调节蛋白激酶(ERK1/2)通路相关蛋白的关联.雄性KM小鼠36只,随机分成4组:生理盐水组、50 mg·kg~(-1)·d~(-1) DBP组、50 mg·kg~(-1)·d~(-1)维生素E(VE)组、DBP+VE组,连续灌胃处理28 d,观察Morris水迷宫结果,检测小鼠脑海马组织的氧化应激(活性氧(ROS)荧光强度、还原型谷胱甘肽(GSH)与丙二醛(MDA)含量)、脑源性神经营养因子(BDNF)、磷酸化cAMP反应元件结合蛋白(p-CREB)、caspase-3水平,Western blot分析ERK1/2及其磷酸化(p-ERK1/2)水平;HE、Nissl染色及Hoechst 33258荧光染色分析脑组织CA1区病理学变化.结果表明,与对照组比较,50 mg·kg~(-1)·d~(-1) DBP组小鼠的学习记忆下降,氧化应激、p-ERK1/2、caspase-3水平上升,BDNF、p-CREB表达下降,差异均有统计学意义(p0.05,p0.01);海马组织CA1病理学损伤及凋亡程度增加.给予抗氧化剂VE处理后,DBP+VE组小鼠的学习记忆上升,氧化应激、p-ERK1/2、caspase-3水平降低,BDNF、p-CREB表达上升,差异均有统计学意义(p0.05);海马组织CA1病理学损伤及凋亡程度降低.由此推测,DBP暴露导致小鼠海马组织CA1病理学损伤、神经元凋亡程度增加、学习记忆下降、其神经行为学改变可以通过添加VE得到缓解,相关生理生化指标测试表明ERK系统应激氧化性损伤机制参与介导了毒理学过程.

Dibutyl phthalate induces neurobehavioral changes in mice and its relationship with physiological and biochemical indexes

To explore the neurobehavioral changes induced by dibutyl phthalate and its relationship with extracellular regulated protein kinases (ERK1/2) pathway in mice. 36 male KM mice were randomly divided into 4 groups (n=9):saline group, 50 mg·kg^-1·d^-1 DBP group, 50 mg·kg^-1·d^-1 vitamin E (VE) group and DBP+VE group. After 28 days of continuous intragastric administration, the results of Morris water maze were observed. And the levels of oxidative stress (reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA)), brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP response element binding protein (p-CREB) were detected in the hippocampus of mice. The levels of ERK1/2 and its phosphorylation (p-ERK1/2) were analyzed by Western blot. In addition, the pathological changes of the CA1 region were examined by H&E, Nissl staining and Hoechst 33258 fluorescence staining. The results show that, compared with the control group, the learning and memory ability of mice was decreased, the levels of oxidative stress, p-ERK1/2 and caspase-3 were increased, whereas the levels of BDNF and p-CREB were decreased in the 50 mg·kg^-1·d^-1 DBP group (p<0.05, p<0.01). Meanwhile the pathological damage and apoptosis of CA1 in hippocampus was increased. After treated with antioxidant VE, the learning and memory ability of mice was increased, the levels of oxidative stress, p-ERK1/2 and caspase-3 were decreased, and the levels of BDNF and p-CREB were increased in DBP+VE group (p<0.05). Also the pathological damage and apoptosis of CA1 in hippocampus was decreased accordingly. Thus, it is concluded that DBP can induce the pathological damage of CA1, increase the neuron apoptosis, decrease the learning and memory, while VE can alleviate the DBP induced neurobehavioral changes. The related physiological and biochemical indexes indicate that the oxidative damage and ERK pathway may be involved in the toxicological process.