A potential inhibitor of rat aortic vascular smooth muscle cell proliferation from the pollen of Typha angustata

By various chromatographic methods, three flavonoids, (2S)-naringenin (1), isorhamnetin 3-O-(2-O-α-l-rhamnopyranosyl) β-d-glucopyranoside (2), typhaneoside (3), and two sterol glycosides, β-sitosterol-3-O-(6-octadecanoyl) β-d-glucopyranoside (4) and β-sitosterol-3-O-(6-octadeca-9Z,12Z-dienoyl) β-d-glucopyranoside (5), were isolated from the pollen of Typha angustata. Their structures were determined on the basis of spectroscopic analyses. The flavonoids (1–3) were evaluated for their effects on the viability and proliferation of rat aortic smooth muscle cells. (2S)-naringenin (1) significantly inhibited cell proliferation in a dose-dependent manner without cytotoxic at concentrations of 30, and 50 μM; it reduced the number of cells following PDGF-BB treatment to 1.83 ± 0.30 × 10⁴ and 2.20 ± 0.60 × 10⁴ cells/well, respectively. These findings suggest that (2S)-naringenin has antiproliferative effects on aortic smooth muscle cells.