Abstract
Silibinin is a chemically defined flavonoid and the main active component of silymarin, a polyphenolic complex from Silybum marianum, which has anti-inflammatory, hepatoprotective and anticarcinogenic properties. Monocytes obtained from healthy individuals were incubated with silibinin to evaluate cell viability, hydrogen peroxide (H2O2) release and tumour necrosis factor-alpha (TNF-α) production by these cells. The duration of treatment and different silibinin concentrations had no significant effect on cell viability. Monocytes showed a dose-dependent inhibitory effect on H2O2 release by phorbol myristate acetate-stimulated monocytes in silibinin concentrations ranging from 6.25 to 50 µg mL−1. Significant inhibition of TNF-α production by lipopolysaccharide-stimulated monocytes was observed at concentrations of 12.5, 50 and 100 µg mL−1 of silibinin. These results suggest that silibinin exerts antioxidant and anti-inflammatory properties on human monocytes through an inhibitory effect on H2O2 release and on TNF-α production, respectively.
Acknowledgement
This research work was supported by FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo), process number: 03/10476-0, Brazil.