Rationale of using Vinca minor Linne dry extract phytocomplex as a vincamine’s oral bioavailability enhancer

摘要

Vincamine is a poorly soluble potent neuroprotector and cerebral vasodilator, used for the treatment forudCNS disorders. In some cases, the bioavailability of pure compounds is strongly influenced by theudco-administration of other constituents, and in some cases, the so called ‘phytocomplex’ may act asudenhancer of absorption of selected phytochemicals. In this paper, the oral bioavailability of vincamineudwhen administered as a standardised Vinca minor L. leaf dry extract rather than pure indole alkaloid isuddemonstrated to be higher.udThe chosen alkaloid-enriched and standardised dry extract was widely characterised by means ofudHPLC–MS, PXRD, DSC, XPS, 13C and 15N solid-state NMR (SSNMR) using pure vincamine as a matter ofudcomparison. Then, the in vitro dissolution performances of the two products and their in vivo bioavailabilityudin rats were evaluated. The sevenfold improvement in oral bioavailability of the dry extract withudrespect to the pure vincamine was ascribed to interactions between the indole alkaloid and the corollaryudof ingredients of the dry extract, giving rise to the protonation of the alkaloid vincamine, thus enhancingudits dissolution in physiological fluids. Present data demonstrate that alkaloid vincamine administered as audwhole plant extract has a higher bioavailability compared to the pure chemical compound.