基于BDNF/TrkB/CREB信号通路探讨核桃油对东莨菪碱导致认知障碍大鼠的保护作用

Effects of walnut oil on scopolamine-induced cognitive impairment in rats based on BDNF/TrkB/CREB pathway

研究显示,膳食营养在改善认知功能衰退、降低痴呆风险方面发挥着重要作用。该研究基于脑源性神经营养因子(brain-derived neurotrophic factor, BDNF)/原肌球蛋白相关激酶B(tropomyosin-related kinase B, TrkB)/环磷腺苷效应元件结合蛋白(cAMP-response element binding protein, CREB)信号通路探讨核桃油对东莨菪碱致认知障碍大鼠的保护作用。将24只SD大鼠随机分为空白对照组、模型对照组、核桃油组。先进行30 d的核桃油灌胃,其他2组给予等体积生理盐水处理。第31天开始模型对照组和核桃油组每日腹腔注射3 mg/(kg·d)东莨菪碱,通过新物体识别和Morris水迷宫测试记忆能力,为期5 d。苏木精-伊红染色法(hematoxylin-eosin staining, HE)染色观察海马组织形态,试剂盒检测脑组织乙酰胆碱(acetylcholine, ACh)含量和乙酰胆碱酯酶(acetylcholinesterase, AChE)活性,蛋白质免疫印迹法测定海马组织突触素(synaptophysin, SYN)、突触后致密蛋白-95(postsynaptic density-95, PSD-95)、BDNF、TrkB、CREB的表达。结果显示,与模型对照组比较,核桃油组的学习记忆能力显著升高;神经元细胞排列变得整齐、结构趋向完整;海马组织的ACh含量增加,AChE活性降低;海马组织中目的蛋白表达均显著升高,提示核桃油对东莨菪碱诱导的认知障碍具有保护作用,其可能机制与激活BDNF/TrkB/CREB信号通路调节突触可塑性有关。

Research has shown that nutrition and diet play a key role in improving cognitive decline and reducing the risk of dementia.This study aimed to investigate the effect of walnut oil on scopolamine-induced cognitive impairment in rats based on the BDNF/TrkB/CREB signaling pathway.24 SD rats were randomly divided into a control group,a model group,and a walnut oil group.First,walnut oil was gavaged for 30 days,and the other two groups were treated with equal volume of saline.On the 31 st day,the model group and walnut oil group were intraperitoneally injected with 3 mg/(kg·d)of scopolamine daily for 5 days.The learning and memory abilities were tested through new object recognition experiments and Morris water maze tests.HE staining was used to observe the pathological morphology of the hippocampus.The acetylcholine(ACh)content and acetylcholinesterase(AChE)activity in the brain tissue were detected using a reagent kit.Western blot was used to detect synaptophysin(SYN),postsynaptic density-95(PSD-95),brain-derived neurotrophic factor(BDNF),tropomyosin-related kinase B(TrkB),and cAMP-response element binding protein(CREB)expression levels in the hippocampus.It found that walnut oil could improve the learning and memory ability of rats in the scopolamine-induced cognitive impairment model,as well as neuronal cell arrangement,and structural integrity.It could also decrease the activity of AChE,increase the level of ACh,and significantly elevate the expression of target proteins in hippocampal tissues.This suggests that walnut oil has an effect on cognitive function in scopolamine-induced cognitive impairment and its possible mechanism is related to the activation of the BDNF/TrkB/CREB signaling pathway to regulate synaptic plasticity.