Use of the antimicrobial peptide Epinecidin-1 to protect against MRSA infection in mice with skin injuries

Methicillin-resistant Staphylococcus aureus (MRSA) causes infections through open skin injuries, and its resistance makes treatment difficult. The antimicrobial peptide Epinecidin-1 (Epi-1) has been reported to possess antibacterial, antifungal, antiviral, and antitumor functions. This study investigated the antimicrobial activity of Epi-1 against skin trauma-mediated MRSA infection in mice. One square centimeter of outer skin was excised from the ventral region of mice, and a lethal dose of MRSA was applied in the presence or absence of methicillin, vancomycin, or Epi-1. While untreated mice and mice treated with methicillin died within four days, mice treated with Epi-1 survived infection. Epi-1 decreased MRSA bacterial counts in the wounded region, enhanced wound closure, and increased angiogenesis at the injury site. Treatment with Epi-1 decreased serum levels of the proinflammatory cytokines TNF-α, IL-6, and MCP-1, and regulated the recruitment of monocytes and clearance of lymphocytes around the wounded region during healing. In conclusion, Epi-1 may be effective at treating clinical MRSA, and may enhance wound recovery when combined with collagen.