Abstract: Objective To investigate the effects of ferulic acid on behavior, activation of microglia in hippocampus and expression of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in autistic model rats, in order to explore a new approach for ASD drug therapy. Methods The autism model was prepared by referring to the Schneider autism model rat method. Forty 7-day-old model rats were randomly divided into valproate(VPA) group and ferulic acid (FA) group. Control rats 20 were randomly selected into NS group. FA group was intraperitoneally injected with ferulic acid 50mg/kg for 21 consecutive days from the 7th day, VPA group and NS group were injected with normal saline. The model was identified by developmental and behavioral tests. After the intervention, the morphological changes of hippocampus were observed by HE staining, the expression levels of IBA-1 were detected by immunofluorescence staining, and the expression levels of IL-1β, IL-6 and TNF-α were detected by enzyme-linked immunosorbent assay. Results Compared with NS group, VPA group had lower body weight, curvy tail or short tail, decreased "sociability" and "social novelty", decreased ability to distinguish social odor, and increased repetitive and stereotypical behavior (P<0.05). The nerve cells in the hippocampus were arranged in disorder, with large space, unclear structure, cell degeneration and inflammatory cell infiltration. The number of activated microglia in hippocampus increased, and the expression levels of IL-1β, IL-6 and TNF-α increased (P < 0.05). After ferulic acid intervention, the pathological damage of hippocampus in FA group was improved compared with VPA group. The number of IBA-1 positive cells and the expression levels of IL-1β and IL-6 decreased (P < 0.05). Conclusion The intervention of ferulic acid can improve the learning and memory ability of the autism model mice, and improve the abnormal development and behavioral performance of the autism model mice to a certain extent, such as impairment of social interaction. Ferulic acid can reduce the number of activated microglia and the expression levels of pro-inflammatory cytokines IL-1β and IL-6 in the hippocampus of autism model rats, thus playing a neuroprotective role.

Key words: autism, microglia cells, interleukin-1β, interleukin-6, ferulic

摘要： 目的 探究阿魏酸早期干预对孤独症谱系障碍(ASD)模型鼠行为、海马区小胶质细胞活化和白介素-1β(IL-1β)、白介素-6(IL-6)及肿瘤坏死因子-α(TNF-α)表达的影响,为ASD的药物治疗探索新途径。方法 自2020年10月—2021年5月,参照Schneider经典造模方法制备孤独症大鼠模型,随机选取7日龄模型组40只分为丙戊酸钠(VPA)组、阿魏酸(FA)组,对照组20只为生理盐水(NS)组。FA组从第7天起连续21d腹腔注射阿魏酸50mg/kg,VPA组和NS组注射等量生理盐水。同时进行模型鉴定。苏木精-伊红染色法(HE)观察各组海马区形态学变化、免疫荧光染色检测电离钙绑定衔接分子-1(IBA-1)的表达水平,酶联免疫吸附剂测定(ELISA)检测IL-1β、IL-6及TNF-α的表达水平。结果 与NS组比,VPA组体重降低、尾部弯曲或短小,“社交性”和“社交新奇性”下降、辨别社交气味的能力下降、重复刻板行为增多(P＜0.05);海马区出现神经炎性病理表现,小胶质细胞活化数量增多,IL-1β、IL-6及 TNF-α的表达水平升高(P＜0.05);阿魏酸干预后,FA组社交能力和对社交气味的分辨能力增强(P＜0.05),海马区病理损伤较VPA组有改善;海马区IBA-1阳性细胞数量减少;促炎性细胞因子IL-1β和IL-6的表达水平降低(P＜0.05)。结论 阿魏酸早期干预能提高ASD模型鼠的学习记忆能力和社交能力,可降低ASD模型鼠海马区活化的小胶质细胞数量和促炎性细胞因子IL-1β,IL-6的表达水平,起到神经保护作用。

关键词: 孤独症, 小胶质细胞, 白介素-1β, 白介素-6, 阿魏酸