芹菜素对Aβ_(1-42)致阿尔茨海默病大鼠海马组织氧化应激和炎症反应的影响

Effects of Apigenin on Oxidative Stress and Inflammatory Reaction in Hippocampus of Rats with Alzheimer′s Disease Induced by Aβ_(1-42)

目的:探讨芹菜素对β-淀粉样蛋白1-42片段(β-amyloid 1-42 fragments, Aβ_(1-42))致阿尔茨海默病(alzheimer′s disease, AD)大鼠海马组织氧化应激和炎症反应的影响及相关机制。方法:按随机数字表法将100只健康SPF级Wistar大鼠分为正常组、模型组、芹菜素低剂量组(20 mg·kg^(-1))、芹菜素高剂量组(40 mg·kg^(-1))和吡拉西坦组(700 mg·kg^(-1))。除正常组外,其它组大鼠采用双侧海马定向注射Aβ_(1-42)的方法制备AD大鼠模型,造模完成后,各组大鼠腹腔注射相应药物,正常组和模型组腹腔注射给予0.9%氯化钠溶液,注射体积为5 mL·kg^(-1),每天1次,疗程28 d。Morris水迷宫实验评价大鼠学习记忆能力;HE染色观察海马组织CA1区神经元病理改变及病理分级;分光光度法检测海马组织超氧化物歧化酶(superoxide dismutase, SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase, GSH-Px)的活性和丙二醛(malondialdehyde, MDA)的含量;ELISA法检测肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-1β(interleukin-1β,IL-1β)、IL-6的水平;Western Blot检测核因子E2相关因子2(nuclear factor E2 related factor 2,Nrf2)、血红素加氧酶1(heme oxygenase 1,HO-1)、胞浆核转录因子-κB p65(nuclear transcription factor-κB p65,NF-κB p65)、胞核NF-κB p65蛋白表达水平。结果:与模型组比较,芹菜素高剂量组大鼠的逃避潜伏期显著缩短(P<0.05),穿越平台次数显著增多(P<0.05);海马组织CA1区神经元病理性形态结构改变明显改善,病理分级显著降低(P<0.05);SOD、GSH-Px活性显著升高(P<0.05),MDA、TNF-α、IL-1β、IL-6水平显著降低(P<0.05);海马组织Nrf2、HO-1蛋白表达量显著升高(P<0.05),胞核NF-κB p65蛋白表达量和胞核NF-κB p65、胞浆NF-κB p65蛋白表达量的比值显著降低(P<0.05)。结论:芹菜素能够抑制Aβ_(1-42)致AD大鼠海马组织氧化应激和炎症反应,改善AD症状,其作用可能与激活Nrf2/HO-1通路、抑制NF-κB核转位有关。

Objective: To explore the effect of apigenin on oxidative stress and inflammatory reaction in hippocampus of rats with Alzheimer′s disease(AD) induced by β-Amyloid protein 1-42 fragments(Aβ_(1-42)) and the related mechanisms.Methods: 100 healthy SPF Wistar rats were randomly divided into normal group, model group, low dose apigenin group(20 mg·kg^(-1)),high dose apigenin group(40 mg·kg^(-1)) and piracetam group(700 mg·kg^(-1)).In addition to the normal group, rats in other groups were injected with A β The AD rat model was prepared by the method of 1-42.After the completion of the model, the corresponding drugs were injected intraperitoneally in each group, and 0.9% sodium chloride solution was injected intraperitoneally in the normal group and the model group, with the injection volume of 5mL o kg^(-1),once a day, for 28 days.Morris water maze test was used to evaluate the learning and memory ability of rats;HE staining was used to observe the pathological changes and grading of neurons in CA1 area of hippocampus;The activity of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px) and the content of malondialdehyde(MDA) in hippocampus were measured by spectrophotometry.Tumor necrosis factor-α(TNF-α),Interleukin-1β(IL-1β) and IL-6 levels were detected with ELISA;nuclear factor E2 related factor 2(Nrf2),heme oxygenase 1(HO-1) and cytoplasmic nuclear factor-κ Bp65(NF-κ B p65) protein expression levels were detected with Western Blot.Results: Compared with the model group, the escape latency of rats in the high dose apigenin group was significantly shortened(P<0.05),and the number of times of crossing the platform was significantly increased(P<0.05);The pathological morphological changes of neurons in CA1 area of hippocampus were significantly improved, and the pathological grade was significantly decreased(P<0.05).The activities of SOD and GSH-Px increased significantly and the content of MDA was decreased significantly(P<0.05).The level of TNF-α,IL-1βand IL-6 decreased significantly(P<0.05).The expression of Nrf2 and HO-1 protein in hippocampus was significantly increased(P<0.05),and the nuclear NF-κ Bp65 protein expression and cytoplasmic NF-κ B p65 protein expression was significantly decreased(P<0.05).Conclusion: Apigenin can inhibit A β_(1-42)causes oxidative stress and inflammatory reaction in hippocampus of AD rats, improves AD symptoms, and its effect may be related to activation of Nrf2/HO-1 pathway and inhibition of NF-κB nuclear translocation.