Functional synergy of antimicrobial peptides and chlorhexidine acetate against gram-negative/ gram-positive bacteria and a fungus in vitro and in vivo

Abstract

Background and purpose: To reduce the resistance and allergic reaction to chlorhexidine acetate (CHA) in the current treatment of (Bacterial vaginosis) BV and (vulvovaginal candidiasis) VVC in female vaginitis. In this study, the antimicrobial activities and mechanism of action of the synergistic effects of antimicrobial peptides (AMPs) HPRP-A1 and HPRP-A2, and CHA, against Gram-negative and Gram-positive bacteria, and one fungus Candida albicans (C. albicans) were investigated in vitro and in mouse and rat vaginitis infection models in vivo. Results: HPRP-A1, HPRP-A2 and CHA showed significant synergistic effects on the antimicrobial activities against different Gram-negative and Gram-positive bacteria and C. albicans. The combined application of HPRP-A2 and CHA exhibited strong synergistic effects in the mouse and rat vaginitis models caused by bacteria or C. albicans. Conclusion: This study may prompt the development of new drug combinations against vaginitis infections, including mixed bacterial and fungal infections and multi-drug-resistant infections.