Plasma-activated water efficacy in the management of experimental wounds infected with Staphylococcus aureus in mice

Abstract

AIM: Evaluation of the antimicrobial and regenerative effect of plasma-activated water (PAW) on a murine model of skin wounds infected with Staphylococcus aureus in CD1 mice. BACKGROUND: Wound healing is a complex and dynamic process that can be affected by various factors including infection. PAW emerged as a promising antimicrobial agent and studies are necessary to evaluate its in vivo efficacy. METHOD: Eighteen female CD1 mice were divided into two groups: infected with MRSA ATCC 43300 and treated with saline solution (control), infected and treated with plasma-activated water (PAW). An 8 mm skin wound model with anti-contraction silicone rings was created. A volume of 50 μL inoculum containing 10⁷ CFU MRSA was used to infect the wounds. At day 7, 12 and 25 post-infection, immunohistochemical analysis of collagen types 1, 3, 4, cytokeratin 10, and VEGF along with bacterial load evaluation of each wound were performed. RESULTS: The bacterial burden (CFU/wound) decreased rapidly in PAW group comparing to control group: 2.01 × 10⁵ vs. 1.58 × 10⁵ (day 7), 0.07 × 10³ vs. 5.6 × 10³ (day 12), <10¹ vs. 9.45 × 10³ (day 25). Wound area reduction was accompanied by significant neoangiogenesis indicated by intense VEGF staining and fibrillar neogenesis highlighted by expression of collagen types 1, 3, and 4. The immunohistochemical staining of cytokeratin 10 was intense, correlating with appropriate wound epithelialization and significantly faster healing for the PAW group (day 13) vs. control group (day 18). CONCLUSION: The obtained results confirm the antimicrobial effect of PAW by significantly reducing the presence of MRSA in experimentally infected wound.

Keywords

• MRSA
• Plasma-activated water
• Experimental wound
• Antimicrobial