Abstract
Phenolic constituents of Salix reticulata (Salicaceae) and antiproliferative activity of an extract and individual compounds
were investigated in immortalized human non-tumorigenic keratinocytes (HaCaT). A MeOH
extract from aerial parts afforded several flavonoids, including luteolin and apigenin
glycosides (2–5 and 9) and catechin (1), two procyanidin fractions, and the phenolic glucosides picein (6), triandrin (7), and salicortin (8). In an adenosine triphosphate assay, the MeOH extract reduced cell viability by
approximately 60 % at a concentration of 100 µg/mL. Cell proliferation was assessed
with a BrdU incorporation ELISA assay. The extract inhibited proliferation of HaCaT
cells in a concentration-dependent manner, with approximately 50 % inhibition at 100 µg/mL.
In time-lapse assays, the extract showed distinct inhibitory effects on cell migration
at concentrations of 12.5, 25, and 50 µg/mL. The activity of selected constituents
was also determined. Luteolin-7-O-β-glucuronide (3) significantly inhibited cell proliferation at concentrations of 10 and 50 µM. In
contrast, luteolin-7-O-β-glucopyranoside (2) and a procyanidin fraction (P1) had only weak effects, while picein (6) and salicortin (8) did not affect cell proliferation. Luteolin-7-O-β-glucuronide (10 µM) and, to a lesser extent, the procyanidin fraction (10 µg/mL)
also inhibited cell migration.
Key words
Salix reticulata
- Salicaceae - flavone glycosides - procyanidins - phenolic glucosides - luteolin-7-O-
β-glucuronide - antiproliferative activity - cell migration
