In vitro and in vivo anti-Vibrio vulnificus activity of psammaplin A, a natural marine compound

Vibrio vulnificus is known to induce severely fulminant and fatal septicemia in susceptible hosts. In the present study, the antimicrobial activity of natural marine product-derived compounds against V. vulnificus, were investigated in vitro and in vivo. Twelve pure compounds were isolated from natural marine products and their inhibitory effects on V. vulnificus-induced cytotoxicity were determined in INT-407 cells. Among the 12 pure compounds tested, treatment with psammaplin A significantly suppressed V. vulnificus-induced cytotoxicity in INT-407 cells. Notably, treatment with psammaplin A (5-50 μg) had improved survival rates compared with that in the untreated mice, when the mice were infected with V. vulnificus intraperitoneally. In addition, the bacterial load of V. vulnificus in several tissues (spleen, liver and small intestine) was significantly lower in psammaplin A-treated mice than in untreated mice. Furthermore, psammaplin A treatment significantly suppressed the growth of V. vulnificus. Taken together, these results indicate that psammaplin A may be a potential agent for the prevention and treatment of V. vulnificus infections.