Unveiling the functional components and anti-Alzheimer's activity of Koelreuteria elegans (Seem.) A.C. Sm. using UHPLC-MS/MS and molecular networking

The use of plant extracts and their phytochemicals as candidates for treating Alzheimer's disease (AD) has been increasingly demanded lately. AD is a progressive neurodegenerative disorder, assumed to be associated with the formation of Aβ plaques and neurofibrillary tangles as well as with neuroinflammation, mediated by cytokines. The metabolomic profiles of Koelreuteria elegans (Seem.) A.C. Sm. leaf and fruit methanol extracts (KEL and KEF, respectively) were explored using UHPLC-MS/MS analysis aided by molecular networking in negative and positive modes for the first time. A total of 139 metabolites of different classes were tentatively identified. The molecular networking (MN) reflected high levels of phenolics and flavonoids. KEL and KEF showed great effects on memory function and spatial learning in behavioral experiments of the injured streptozotocin (STZ)-treated mice. The plant extracts led to pronounced improvement in the histopathological profile of the cerebral cortex of the injured STZ-treated mice. The effect of extracts on the levels of neuroinflammatory mediators TNF-α, NF-κB and IL-1β in AD-induced mice was assessed. Both extracts reduced all these markers of inflammation and neurodegeneration in AD.