Effects of Vitex rotundifolia on radical scavenging and nitric oxide production

SUMMARY Vitex rotundifolia (V. rotundifolia) has been used for treating headache, dizziness, toothache andremoval of fever as a traditional medicine in Korea. In the present study, we examined theantioxidant and anti-inflammatory activities of 85% methanol extract of V. rotundifolia. In variousradical scavenging assays, V. rotundifolia exhibited strong scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl free radical, superoxide radical, nitric oxide. To elucidate the anti-inflammatoryproperties of V. rotundifolia, we investigated the inhibition effects of nitric oxide production inIFN-gamma and LPS-stimulated mouse peritoneal macrophages. V. rotundifolia suppressed nitricoxide production, iNOS and COX-2 expression dose-dependently through suppression of NF-eBactivation without notable cytotoxicity. These findings mean that V. rotundifolia may be beneficialin oxidative stress-mediated inflammatory disorders.Key words: Vitex rotundifolia; Antioxidant; Anti-inflammatory INTRODUCTION Inflammation is a defense mechanism to minimizethe damage by infection or irritation and may bereferred to as the innate cascade including variouscells and cytokines (Zamora et al., 2000). It ischaracterized by redness, heat, swelling, pain anddysfunction of the organs. Macrophages play acentral role in host defense and maintenance as amajor immune cell in inflammation since pro-inflammatory mediators such as nitric oxide (NO),prostagladins (PGs) and cytokines are secreted byactivated macrophage.NO produced by one of three kind of NO synthase(NOS) that nNOS (neuronal NOS), endothelialNOS (eNOS), inducible NOS (iNOS) from L-arginine.NO, produced by nNOS and eNOS in nanomolarconcentration, play an important role as a neuro-transmitter and vasodilator. However, overproductionof NO, mediated by iNOS, intimately correlatedwith the pathological conditions in inflammationrelated diseases (Wang et al., 2003). COX (cyclooxy-genase), another key enzyme in inflammation, is therate-limiting enzyme that catalyzes the formationof PGs from arachidonic acid. Levels of PGsincrease early in the step of inflammation. LikeNOS, COX also exists in both constitutive (COX-1)and inducible (COX-2) forms. It is well known thatthe COX-1 is a housekeeping protein in mosttissues and it catalyzes the synthesis of PGs fornormal physiological functions while COX-2mediates an inflammatory response. It is well