【作者】 王进；

【导师】 苗静；

【作者基本信息】 新疆大学 ， 生物学， 2023， 硕士

【摘要】 阿尔兹海默症（Alzheimer’s Disease,AD）,是指以进行性不可逆转的记忆力及认知功能下降为主要临床特征的中枢神经退行性疾病,多发生于老年及老年前期。目前,随着社会老龄化进程加快,AD发病率逐年升高,由于其发病机制复杂,用药临床效果不佳,因此开发抗AD的新药已经当前研究的热点。恰玛古具有抗缺氧、抗炎、抗氧化、抗衰老等功能,具有潜在的抗AD作用,本研究通过体内外实验筛选恰玛古中抗AD的有效部位,对有效部位抗AD活性的机制及其活性成分进行研究。主要研究方法及结果如下:（1）恰玛古抗AD有效部位的筛选:本研究通过胆碱酯酶抑制活性、抗氧化活性、H₂O₂损伤PC12细胞模型和拟痴呆小鼠模型来评价恰玛古各活性部位的抗AD活性,以筛选其抗AD的有效部位。体外实验结果表明,相较于其他活性部位,恰玛古乙酸乙酯活性部位（BREE-Ea）具有较好的胆碱酯酶抑制活性、抗氧化能力、对H₂O₂损伤的PC12细胞的保护作用;小鼠体内实验结果表明,与其他活性部位相比,BREE-Ea可以更好的降低拟痴呆小鼠脑组织中乙酰胆碱酯酶、β分泌酶1、丙二醛及炎症因子水平,提高抗氧化酶水平,提高拟痴呆模型小鼠的认知和记忆能力。（2）BREE-Ea抗AD的初步作用机制:通过测定体外细胞模型和体内拟痴呆小鼠模型的相关指标,对BREE-Ea抗AD活性的机制进行初步研究。结果显示,在体外BREE-Ea可以提高抗氧化酶超氧化物歧化和谷胱甘肽过氧化物酶活力、降低脂质过氧化产物丙二醛含量和减少乳酸脱氢酶的胞外释放,从而降低PC12细胞内ROS水平,提高H₂O₂损伤的PC12细胞存活率;在体内,BREE-Ea可以降低拟痴呆小鼠脑组织中乙酰胆碱酯酶、β分泌酶1、丙二醛及炎症因子水平,提高抗氧化酶水平,来维持神经细胞的完整性,减少Aβ沉积和磷酸化Tau蛋白产生,从而发挥抗AD作用。（3）BREE-Ea抗AD活性成分研究:利用UPLC-MS技术和系统分离获得BREE-Ea中的化学成分,通过TCMSP数据库查找这些化学成分对应的与AD相关疾病和相关靶点,筛选BREE-Ea中潜在抗AD的活性成分,研究表明BREE-Ea中具有潜在的活性化合物有81个。本研究通过体内外实验筛选出恰玛古中抗AD的有效部位为BREE-Ea,之后对BREE-Ea抗AD的作用机理及潜在活性成分进行探究,为新疆恰玛古资源的精深开发与利用提供依据,也为抗AD药物研发与先导化合物发现提供思路与基础。更多还原

【Abstract】 Alzheimer’s Disease（AD）is a central neurodegenerative disease characterized by progressive and irreversible decline in memory and cognitive function.At present,with the acceleration of the aging process of society,the incidence rate of AD is increasing year by year,pathogenesis is complex,and the clinical effect is poor.Therefore,the development of new drugs against AD has become a hot spot of current research.Traditional Chinese medicine has its own unique advantages in the treatment of AD due to its multi component and multi target characteristics.Brassica rapa L.has anti hypoxia,anti-inflammatory,antioxidant,anti-aging and other functions,and has potential anti AD effect.In this study,the effective fractions anti-AD in Brassica rapa L.were selecte.Then,the mechanism of anti-AD activity of the active fraction was preliminatively studied,and the active components were studied.Main research methods and results are as follows:（1）Screening of active fractions of Brassica rapa L.against AD.In this study,the effective fractions of Brassica rapa L.against AD were screened through determined the cholinesterase inhibitory activity,antioxidant activity,and established H₂O₂-induced in PC12 cell model and AD mouse model.The experiment showed that the BREE-Ea had better cholinesterase inhibitory activity,antioxidant ability and protective effect on PC12 cells damaged by H₂O_2-induced compared to other active fractions.In vivo experiments showed that BREE-Ea could better reduce the levels of acetylcholinesterase,β-secretase 1,malondialdehyde inflammatory factors,and improve the levels of antioxidant enzymes in the brain tissue to increase the cognitive and memory ability of AD mouse model.（2）Preliminary mechanism of BREE-Ea against AD.The mechanism of anti-AD activity of BREE-Ea was preliminarily studied by measuring the relevant indexes cell model in vitro and AD mouse model in vivo.The results showed that BREE-Ea could reducing the level of ROS in PC12 cells by increase the activities of antioxidant enzymes superoxide dismutase and glutathione peroxidas,reduce the content of malondialdehyd,the product of lipid peroxidation,and reduce the extracellular release of lactate dehydrogenas,and reducing H₂O₂-induced damaged of PC12 cells.In vivo results showed that BREE-Ea could play an anti AD role by reduce levels of acetylcholinesteras,βsecretase,malondialdehyde,and inflammatory factors,increasing levels of antioxidant enzymes to maintain the integrity of nerve cells and reduce deposition of Aβand phosphorylation of phosphorylated Tau protein.（3）Research on the active compounds of BREE-Ea against AD.Screening of potential anti-AD active constituents in BREE-Ea by systematic isolation and UPLC-MS.We found that 81 compounds of BREE-Ea have potential anti AD.In this study,BREE-Ea was selected as the effective fraction anti-AD from Brassica rapa L.through in vivo and in vitro experiments,and then the mechanism of action and potential active ingredients of BREE-Ea anti-AD were explored,which could provide a basis for the in-depth development and utilization of Brassica rapa L.resources in Xinjiang.It also provides theory and basis for the development of anti-AD drugs and the discovery of lead compounds.更多还原