Honey-induced macrophage stimulation: AP-1 and NF-κB activation and cytokine production are unrelated to LPS content of honey.

Honey is well known for its wound healing properties although the cellular and molecular mechanisms underlying honey-stimulated healing process are still poorly understood. The present study was intended to characterize the stimulation of Raw 264.7 murine macrophages in response to thyme honey. Honey induces significant increase in PGE2 production, and overexpression of both COX-2 and TNF-α (p<0.001). This increase was concomitant with overexpression and activation of the AP-1 and NF-κB transcription factor subunits. The small LPS content of honey could not, by itself, account for the reported observations. These results suggest that other thyme honey components participate in the stimulation of cytokine production required for effective wound healing process.