New prenylated flavonoid glycosides derived from Epimedium wushanense by β-glucosidase hydrolysis and their testosterone production-promoting effects

Six new prenylated flavonoid glycosides, including four new furan-flavonoid glycosides wushepimedoside A–D (1–4) and two new prenyl flavonoid derivatives wushepimedoside E–F (5–6), and one know analog epimedkoreside B (7) were isolated from biotransformation products of the aerial parts of Epimedium wushanense. Their structures were elucidated according to comprehensive analysis of HR-MS and NMR spectroscopic data, and the absolute configurations were assigned using experimental and calculated electronic circular dichroism (ECD) data. The regulatory activity of compounds 1–7 on the production of testosterone in primary rat Leydig cells were investigated, and 4 and 5 exhibited testosterone production-promoting activities. Molecular docking analysis suggested that bioactive compounds 4 and 5 showed the stable binding with 3β-HSD and 4 also had good affinity with Cyp17A1, which suggested that these compounds may regulate testosterone production through stimulating the expression of the above two key proteins.