GC/MS-Based Urine Metabolomics Study On The Ameliorative Effect Of Xanthoceras Sorbifolia Extract On Alzheimer’s Disease In Mice

Objective:Alzheimer’s disease（AD）,the most common type of dementia,has an unclear etiology and there are no drugs that work relatively well in current research.There is a significant positive correlation between the onset of Alzheimer’s disease and age,and as the world’s population grows older,Alzheimer’s disease has placed a significant economic burden on society.There is no cure for Alzheimer’s disease,but effective drug therapy can improve the quality of patient survival.However,the drugs used to treat Alzheimer’s disease all exhibit large side effects,so the search for new potential drugs to treat Alzheimer’s disease is an urgent need for research.Studies on the improvement of Alzheimer’s disease by extracts of Xanthoceras sorbifolia have been increasing in recent years,but their therapeutic mechanisms have not been fully elucidated.Therefore,in this experiment,we induced dementia model mice by D-galactose combined with Aβ_25-35,examined the learning and memory ability of mice by using morris water maze test,and observed the hippocampal tissue structure of mice by brain tissue section to verify the mouse dementia model as well as to analyze the treatment effect.The urine of mice with different interventions applied was analyzed by gas chromatography-mass spectrometry for non-targeted metabolomics,and the pathogenesis of Alzheimer’s disease was analyzed at the metabolite level by metabolomics,and the improvement mechanism of Alzheimer’s disease was further investigated by the extract of Xanthoceras sorbifolia from a metabolomics perspective.Methods:Ethanol and petroleum ether were used as solvents to prepare the extracts from the husks and seed kernels of Xanthoceras sorbifolia.The dementia model mice were induced by subcutaneous injection of D-Gal combined with hippocampus injection of Aβ_25–35 under a brain stereotaxic apparatus and the model was validated by behavioral experiments and the intervention effect of drugs was evaluated after the model was established.The experimental groups were:divide into the control check（CK）,the AD model group（AD）,the shamoperated group（SO）,the Donepezil treatment group（DON）,the husks extracts high dose treatment group（XANH）,the husks extracts low dose treatment group（XANL）,the petroleum ether extract of the seed kernel（PET）and the Ethanolic extract of the seed kernel（ETH）Different drug interventions were given to detect behavioral changes,and pathological changes in the hippocampal region were observed by brain tissue sections,and urine was collected from mice and subjected to GC/MS non-targeted metabolomics analysis to analyze change pattern of metabolome under different intervention conditions.Results:1.Successful preparation of the ethanolic extract of Xanthoceras sorbifolia husks and ethanolic extract of Xanthoceras sorbifolia seeds showed that the total saponin content was 69.75%in the ethanolic extract of Xanthoceras sorbifolia husks and 46.07%in the petroleum ether extract of Xanthoceras sorbifolia seeds,indicating that the relative content of saponin is higher in Xanthoceras sorbifolia husks.2.Behavioral experiments and histopathological sections showed that the dementia model The mice were successfully established,in which mice intervened with donepezil,low-dose ethanolic extract of Xanthoceras sorbifolia husks,ethanolic extract of Xanthoceras sorbifolia seeds and petroleum ether extract showed a significant reduction in latency compared to AD model mice（P<0.05）,as well as a significant reduction in lesions on histopathological sections of the brain.However,the mice intervened with high-dose ethanolic extract of Xanthoceras sorbifolia showed some shortening of latency in behavioral experiments but no significant difference compared with the AD model group（P>0.05）,and the lesions on brain histopathological sections were similar to those of the AD model group.3.After non-targeted metabolomics analysis,14potential biomarkers were identified in mouse urine,and seven important metabolic pathways were outlined.These include the tricarboxylic acid cycle,glyoxylate and dicarboxylic acid metabolism,metabolic pathways of glutathione,metabolism of taurine and hypotaurine,interconversion pathways of pentose and glucuronide,and biosynthetic pathways of primary bile acid biosynthesis.Conclusions:1.D-galactose combined with Aβ_25-35 is an effective way to induce dementia model in mice and can be used to establish Alzheimer’s disease-related animal models.2.There is an effective improvement of learning and memory ability in the mice of the dementia model by the extract of Xanthoceras sorbifolia,but when high doses of ethanolic extract of Xanthoceras sorbifolia husks are used,the improvement is not obvious,which may be related to the impurity components outside the saponin of the extract of Xanthoceras sorbifolia husks.3.The study suggests that the extract of Xanthoceras sorbifolia may have protective effects on mice in dementia models through energy metabolism,alleviation of neuroinflammation,and antioxidant,which may be produced by Xanthoceraside as well as phenolic anti-inflammatory substances in Xanthoceras sorbifolia.This study reveals the potential pathogenesis of Alzheimer’s disease and the potential therapeutic mechanism of Xanthoceras sorbifolia,suggests relevant biomarkers,provides some reference for new drug research,and provides more basis for the clinical application of Xanthoceras sorbifolia.