Abstract
Green tea is an aqueous infusion of the dried unfermented leaves of Camellia sinensis (family Theaceae), for which numerous biological activities have been reported, including antimutagenic, antibacterial, hypocholesterolemic, antioxidant, antitumor and cancer preventive activities. Aggregatibacter actinomycetemcomitans is implicated in the etiology of aggressive periodontitis and chronic periodontitis. We previously reported that LPS from Aggregatibacter actinomycetemcomitans(Aa-LPS)had strong cytotoxic effects against human leukemia cell lines(HL60 cells, THP-1 cells)and human gingival fibroblasts. The purpose of this study was to investigate the anticytotoxic effect of green tea catechin on Aa-LPS. When the cell, Aa-LPS, and the catechin components(EGCg, ECg, C and GC)were incubated, EGCg and Cg showed a strong anticytotoxic effect on Aa-LPS. Furthermore, when the catechin-pretreated cells and Aa-LPS were incubated, EGCg and Cg showed a strong anticytotoxic effect on Aa-LPS. Thus, it was suggested that the gallate moiety included in green tea catechins showed anticytotoxic effects against LPS from Aggregatibacter actinomycetemcomitans.
