Carvacrol has the priming effects of reactive oxygen species (ROS) production in C6 glioma cells

Carvacrol (5-isopropyl-2-methylphenol) is the major component of Plectranthus amboinicus. Several studies have shown that carvacrol has antibacterial, antifungal and insecticidal effects, but the mechanisms that govern these processes are unclear. Reactive oxygen species (ROS) play a major role in host defence eradication of microorganisms. In this study, we provide evidence that carvacrol has priming effects on ROS production in C6 glioma cells. By viability assay, carvacrol was not cytotoxic to C6 cells at levels below 300 µM. We pretreated C6 cells with or without carvacrol and stimulated them with LPS/TPA, after which the C6 cells produced more ROS in TPA/LPS with carvacrol than in LPS/TPA alone. Thus, carvacrol has priming effects on ROS production during stimulation by bacterial cell wall components. Our research provides a possible mechanism that underlies the antimicrobial effects of carvacrol.