Synergistic Antimicrobial Activity of Epinecidin-1 and Its Variants with Antibiotics Against Nosocomial Pathogens: Implications for In Vivo Wound Healing

In this study, we investigated the antimicrobial properties of the antimicrobial peptide (AMP) epinecidin-1 and its variants against a range of nosocomial bacterial pathogens. The bacteriostatic effects on Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Streptococcus pneumoniae, and Staphylococcus aureus were evaluated using the microbroth dilution technique. Mechanistic insights into the antimicrobial action were studied through acridine orange and ethidium bromide (AO/EtBr) staining, which revealed the ability of AMPs to form pores in bacterial membranes. Furthermore, the wound healing efficacy of these peptides was assessed in vivo using rat model, where they significantly accelerated the healing process. Following the identification of their bacteriostatic activity against pathogenic strains, we also examined the effects of combining these AMPs with conventional antibiotics, namely ampicillin, kanamycin, and vancomycin. Epinecidin-1 and its variants displayed synergistic and additive interactions with these antibiotics at certain concentrations. This combination approach is particularly promising for treating infections in both human and livestock populations, thereby potentially mitigating the risk of environmental pathogen outbreaks and complications of multidrug resistance. In summary, our findings suggest that epinecidin-1 and its variants not only exhibit potent antimicrobial and wound healing properties but also enhance the efficacy of traditional antibiotics. These characteristics make them strong candidates for clinical and industrial applications aimed at managing bacterial pathogenicity.