Comparative Effects of the Potent Antioxidant 3,5-Dihydroxy-4-methoxybenzyl Alcohol and Gallic Acid on the Growth and Death of RAW264.7 Macrophages and Lung Cancer A549 Cells In Vitro

DHMBA, a novel antioxidant derived from oyster, exhibits dual properties that block oxidative stress by acting as a radical scavenger in various cells. DHMBA has been shown to play a pharmacological role by exerting anti-macrophage and anti-cancer effects. Gallic acid, which is widely distributed in edible plants, exhibits a potent antioxidant activity. In this study, we compared the effects of DHMBA and gallic acid using inflammatory macrophages (RAW264.7 cells) and human lung cancer cells (A549 cells) in vitro. In these cells, we demonstrated that DHMBA at comparatively lower concentrations (1 or 10 µM) significantly affected cell proliferation and stimulated cell death, resulting in a decrease in cell number. Gallic acid at 1 and 10 μM did not affect the proliferation or death of RAW264.7 and A549 cells. DHMBA may be a potent antioxidant that regulates cell function. Despite having the same molecular weight, the chemical structure of DHMBA and gallic acid exerted different effects. Notably, the combined DHMBA and gallic acid with comparatively lower concentrations (1 and 10 μM) showed potent effects in suppressing the proliferation of RAW264.7 and A549 cells. However, this combination did not induce a significant effect on cell death. Thus, the effects of DHMBA were potentiated in the presence of the antioxidant gallic acid. This finding suggests a potential effect induced by the combined antioxidants. This study provides a new strategy for disease prevention using the strong antioxidants DHMBA and gallic acid.