基于转录组学与代谢组学的有氧运动改善大鼠阿尔茨海默病作用机制研究

关键词：有氧运动  转录组学  代谢组学  阿尔茨海默病  作用机制

Keywords:aerobic exercise  transcriptomics  metabolomics  Alzheimer’s disease  mechanism

摘要：

      摘要 目的：探究有氧运动对阿尔茨海默病的作用靶点和作用机制。 方法：使用雄性清洁级Wistar大鼠32只，随机分为空白组、模型组、阳性药组、有氧运动组。分别对阳性药组和有氧运动组给予0.45g/kg/d的盐酸多奈哌齐片和针对性有氧运动干预，4周干预后，通过Morris水迷宫评估大鼠的学习记忆能力，苏木素-伊红染色观察海马组织病理学变化。结合转录组学和代谢组学对脑组织进行测序和筛选差异代谢物，分析与疾病进展相关的关键基因和代谢物，并通过整合分析聚焦关键基因的表达。 结果：水迷宫实验结果表明，有氧运动显著改善了D-半乳糖诱导的阿尔茨海默病模型大鼠的学习和认知能力。病理染色显示，模型组大鼠海马CA1区椎体细胞数量减少，细胞核质深染，细胞固缩，排列松散紊乱，胞核与胞质界限模糊，间隙变大。有氧运动组大鼠海马神经元细胞结构较为清晰，趋于完整，细胞间隙有变小趋势，视野内未见大范围的神经元固缩，体积相对正常。转录组学筛选出吲哚胺2，3-双加氧酶1（indoleamine 2，3-dioxygenase 1，IDO1）、色氨酸2，3-双加氧酶2（tryptophan 2，3-dioxygenase，TDO2）、丛状蛋白B1（Recombinant Plexin B1，PLXNB1）、三联基序蛋白11（tripartite motif protein 11，TRIM11）的4个基因为主的关键基因，代谢组学筛选出10个差异代谢物，包括N-甲酰基犬尿氨酸、色氨酸、犬尿氨酸、5-羟色胺、5-羟色氨酸、肌酸、N-乙酰天冬氨酰谷氨酸、组氨酸、羟脯氨酰异亮氨酸、吡哆醇。该研究表明有氧运动能显著提高了D-半乳糖诱导的阿尔茨海默病模型大鼠的学习记忆能力，减轻了海马神经CA1区神经元的损伤和减少，通过整合分析发现色氨酸、犬尿氨酸、5-羟色胺及5-羟色氨酸的含量直接由IDO1和TDO2调控生成。 结论：IDO1和TDO2是有氧运动治疗阿尔茨海默病的重要靶点，保护神经元、减少氧化应激炎症是有氧运动治疗阿尔茨海默病的关键机制。

Abstract:

      Abstract Objective： To explore the targets and mechanisms of aerobic exercise on Alzheimer’s disease (AD). Method： Thirty-two male clean-grade Wistar rats were randomly assigned to one of four groups: control, model，positive drug and aerobic exercise. After intervention， the Morris water maze was employed to assess the learning and memory capabilities of the rats， and hematoxylin and eosin staining was utilized to observe pathological changes in hippocampal tissue. Transcriptomic and metabolomic analyses were conducted to identify differential metabolites and key genes associated with disease progression， with a focus on the expression of key genes through integrated analysis. Result： The water maze experiment showed that the aerobic exercise group significantly improved the learning and cognitive abilities of D-galactose-induced Alzheimer's disease model rats. Pathological staining showed a decrease in the number of cells in the hippocampal CA1 region of the model group rats， characterized by deep staining of the nucleus and cytoplasm， cell shrinkage， loose and disordered arrangement， blurred boundaries between the nucleus and cytoplasm， and increased gaps. The cell structure of hippocampal neurons in the aerobic exercise group of rats was relatively clear and tends to be complete， with a decreasing trend in intercellular gaps. No large-scale neuronal shrinkage was observed in the field of view， and the cell volume appeared normal. Transcriptomics screened out key genes mainly including four genes： indoleamine 2，3-dioxygenase 1 （IDO1）， tryptophan 2，3-dioxygenase 2 （TDO2）， plexin B1 （PLXNB1）， and tripartite motif protein 11 （TRIM11）. Metabolomics screening identified ten differential metabolites， including N-formylcarnitine， tryptophan， Kynurenine， 5-hydroxytryptamine， 5-hydroxytryptophan， creatine， N-acetylaspartate glutamate， histidine， Hydroxyprolyl-Isoleucine， and pyridoxine. This study showed that aerobic exercise significantly improved the learning and memory abilities of D-galactose-induced AD model rats， alleviated the damage and reduction of hippocampal CA1 neurons. Integrated analysis found that the content of tryptophan， kynurenine， 5-hydroxytryptamine， and 5-hydroxytryptophan was directly regulated by IDO1 and TDO2. Conclusion： IDO1 and TDO2 are important targets for aerobic exercise in the treatment of AD. The neuroprotective effects and reduction of oxidative stress and inflammation are the key therapeutic mechanisms of aerobic exercise in AD.