POTENCIAL TERAPÊUTICO DE CINAMALDEÍDO NO TRATAMENTO DE FERIDAS CUTÂNEAS CRÔNICAS

Abstract

Currently, there is a great demand for products extracted from plants that have antimicrobial activity and that also benefit the cicatrization process. This is mainly due to the increase in the prevalence of isolates resistant to the different types of antibiotics marketed. Infected wounds are a serious public health problem in the world, being common in patients with burns and ulcers. Cinnamaldehyde, the major compound of the cinnamon extract, has been studied for its antimicrobial and immunomodulatory properties. However, little is known about its effects on bacteria present in infected wounds such as Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus, nor on its healing properties. Thus, this study aims to evaluate the effect of cinnamaldehyde on the virulence and viability of P. aeruginosa, E. faecalis and S. aureus in vitro, as well as its in vivo effects on infection and healing. Initially, microdilution experiments were performed to evaluate the minimal inhibitory concentration and minimal bactericide. Next, the effect of subinhibitory concentrations of cinnamaldehyde were tested on the production of virulence factors by these bacteria. The effects of cinnamaldehyde were evaluated in vivo in a model of systemic infection induced by S. aureus in Galleria mellonella and in a model of wound healing of P. aeruginosa infected in mice. It was observed that cinnamaldehyde presents satisfactory antimicrobial activity against the three species of bacteria evaluated, being able to interfere with the growth, viability for the three species analyzed and production of virulence factors such as biofilm production, hemolytic activity, adhesion, metabolism and Reduction of serum resistance in the isolates of Staphylococcus aureus and Pseudomonas aeruginosa, without causing adaptation of these microorganisms. It was further observed that the treatment protected G. mellonella against S. aureus infection by reducing bacterial load and increasing larval survival. When evaluated in a wound healing model in mice, cinamaldehyde reduced healing time in P. aeruginosa infected wounds, and reduced the microbial population in the lesion bed by 50%. The healing effects of cinnamaldehyde were reversed in animals treated systemically with HC-030031, antagonist to the transient potential receptor ankyrin 1 (TRPA1), targeting cinamaldehyde in vivo. We conclude that cinnamaldehyde, the major compound of cinnamon, may be recommended as a new therapeutic candidate in the healing of infected wounds.