Resveratrol increases phagocytosis and lipopolysaccharide-induced interleukin-1β production, but decreases surface expression of Toll-like receptor 2 in THP-1 monocytes

THP-1 monocytes were used to evaluate the effects of physiological levels of resveratrol aglycone, resveratrol-3-O-glucuronide, resveratrol-4′-O-glucuronide, and resveratrol-3-O-sulfate on phagocytosis, IL-1β, IL-1α, and IL-18 production, viability, and TLR2 and TLR4 expression. THP-1 cells were treated with 1, 5, 10, and 15 μM resveratrol or metabolites. Resveratrol-3-O-glucuronide, resveratrol-4′-O-glucuronide, and resveratrol-3-O-sulfate had no effect on the functional parameters tested. Resveratrol aglycone increased phagocytosis at concentrations of 5, 10, and 15 μM and LPS-induced IL-1β production at concentrations of 10 and 15 μM. Expression of TLR4 increased slightly after resveratrol treatment, but surface expression of TLR2 was reduced as resveratrol concentrations increased. Our data suggest that resveratrol may be effective in modulating monocyte function in an environment where there is direct exposure to the aglycone, such as at the gut epithelium.