Synergic anticandidal effect of epigallocatechin-O-gallate combined with amphotericin B in a murine model of disseminated candidiasis and its anticandidal mechanism

In the present study, we investigated synergic anticandidal effect of epigallocatechin-O-gallate (EGCG) in a murine model of disseminated candidiasis caused by Candida albicans. In addition, its mechanism was examined. In the animal system, EGCG-given BALB/c mice group intraperitoneally (i.p.) before intravenous (i.v.) inoculation with viable C. albicans yeast cells survived longer than diluent-received (control) mice group (p<0.05). EGCG treatment inhibited the hyphal formation from the yeast form of C. albicans, causing growth-inhibition of the candidal cells. In experiments determining synergic effect, mice given diluent (control), Amp B (amphotericin B; 0.5 mg/kg of body weight), or EGCG (2 mg/kg) had mean survival times (MST) of approximately 10.9, 11.7, and 13.9d, respectively. However, mice administered combination of Amp B (0.5mg/kg) plus EGCG (2 mg/kg) had a MST value of 42.1 d, surviving an average of app. 30 d longer than the Amp B alone-received mice groups. The MST value from the combination-treated mice groups was much greater than MST value from mice groups that received four times the Amp B dose. These results indicate that EGCG, which has anticandidal activity causing blockage of the hyphal formation, has the synergism combined with Amp B against disseminated candidiasis.