Antioxidant and Anti-Inflammatory Effects of Various Cultivars of Kiwi Berry (Actinidia arguta) on Lipopolysaccharide-Stimulated RAW 264.7 Cells

The present study evaluated the total phenolic and flavonoid contents as well as total antioxidant capacity (TAC) of three cultivars of Actinidia arguta Planch. kiwi berries; cv. Mansoo (Mansoo), cv. Chiak (Chiak), and cv. Haeyeon (Haeyeon). In addition, the anti-inflammatory effects of the three cultivars of kiwi berries were investigated using a lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage cell line. Mansoo had the highest total phenolic content and TAC among the three cultivars, whereas Chiak had the highest total flavonoid content. The total antioxidant capacities of the kiwi berry extracts were more strongly correlated with total phenolic content than with total flavonoid content. The kiwi berry extracts suppressed the secretion of pro-inflammatory cytokines, including interleukin-6 and tumor necrosis factor-alpha, from LPS-stimulated RAW 264.7 cells. The release of nitrite, an indirect indicator of nitric oxide, was also ameliorated by pre-treatment with the kiwi berry extracts in a dose-dependent manner. Cellular-based measurements of antioxidant capacity exhibited that the kiwi berry extracts had cellular antioxidant capacities. Such cellular antioxidant effects are possibly attributed to their direct antioxidant capacity or to the inhibition of reactive oxygen species generation via anti-inflammatory effects. Our findings suggest that kiwi berries are potential antioxidant and anti-inflammatory agents.