[n-butanol fraction of ethanol extract of Periploca forrestii Schltr.: its active components, targets and pathways for treating Alcheimer's disease in rats].

Objectives: To investigate the active components and possible mechanisms of n-butanol fraction of Periploca forrestii Schltr. ethanol extract for treating Alzheimer's disease (AD).

Methods: The active components of n-butanol fraction of Periploca forrestii Schltr. ethanol extract were analyzed using UPLC-QE-MS technique. In a SD rat model of AD induced by treatment with AlCl₃ and D-gal, the therapeutic effects of low, moderate and high doses of the n-butanol fraction, saline, and donepezil hydrochloride were evaluated using ELISA, HE and Nissl staining, immunohistochemistry and Western blotting. The therapeutic mechanisms of the n-butanol fraction were explored using network pharmacology and molecular docking.

Results: Seventeen active components were identified from the n-butanol fraction of Periploca forrestii Schltr. ethanol extract, including phenylpropanoids, flavonoids, anthraquinones, triterpenoids, steroids, and volatile oils. In the rat models of AD, treatment with the n-butanol fraction significantly lowed AChE content in the hippocampus, increased the contents of ACh, SOD, CAT, and GSH-Px, enhanced the expressions of neuronal apoptotic factors Bcl-2, PI3K, Akt, p-PI3K, and p-Akt, and reduced the expressions of Bax and caspase-3 proteins. The treatment also dose-dependently up-regulated hippocampal expressions of Nrf-2, HO-1 and BDNF and down-regulated Keap-1, Aβ and Tau expressions. Bioinformatics analysis identified 14 key intersected targets (including TNF, AKT1 and ESR1) between the n-butanol fraction and AD.

Conclusions: The therapeutic effect of n-butanol fraction of Periploca forrestii Schltr. ethanol extract in AD mice is mediated by its multiple active components that regulate multiple targets and pathways.