AVALIAÇÃO DA ATIVIDADE ANTIBACTERIANA E CICATRIZANTE DA LECTINA STELL ISOLADA DA FOLHA DE Schinus terebinthifolius RADDI

Abstract

Staphylococcus aureus is commonly found in wound infections where this pathogen compromises skin repair. The lectin isolated from Schinus terebinthifolius leaves (called SteLL) has antimicrobial and antivirulence action against S. aureus. The study evaluated the effects of topical administration of SteLL on wounds of mice infected with S. aureus. A total of 72 C57/BL6 mice (6-8 weeks old) were allocated into four groups: (i) uninfected wounds; (ii) infected wounds treated with 32 µg/ml SteLL solution; (iv) infected wounds treated with 64 µg/mL SteLL solution. A lesion of approximately 8 mm in diameter was induced in the dorsal region of each animal and infected by S. aureus 432170 (4.0 x 106 CFU/wound). Daily treatment started 1 day post-infection (dpi). Topical application of both SteLL concentrations showed a decrease in the severity of S. aureus infection, results that correlate with the decrease in bacterial load in the wound bed, significantly reducing the healing of infected wounds up to 7thdpi, when compared to untreated infected lesions (1.95-4.55-fold and 1.79-2.90-fold reductionsfor SteLL at 32 µg/mL and 64 µg/mL, respectively). SteLL-based treatment also altered the severity of wound infection and reduced bacterial load (12-fold to 72-fold for 32 µg/mL; and 14-fold to 282-fold for 64 µg/mL). Wounds treated with SteLL showed greater collagen deposition and restoration of skin structure compared to the other groups. Bacterial load and levels of inflammatory markers (IL-6, MCP-1, TNF-α and VEGF) were also reduced by both SteLL concentrations. These results corroborate the reported anti-infective properties of SteLL,making this lectin a leading candidate for the development of alternative agents for the treatment of S. aureus infected skin lesions.