Burn wound healing is a complex process that involves the repair of injured tissues and the control of infection to diminish the scar formation, pain, and discomfort associated with such injuries. The aim of this research was to formulate and optimize a self-nanoemulsion drug delivery system based on the use of coconut oil and loaded with simvastatin. Coconut oil possesses antiinflammatory and antibacterial activity, and simvastatin has interesting properties for promoting the wound-healing process because it increases the production of the vascular endothelial growth factor at the site of injury. The Box-Behnken design was employed for the optimization of the coconut oil-simvastatin self-nanoemulsion drug delivery system. The prepared formulations were characterized according to globular size and their activity in the healing of burn wounds by assessing the mean wound diameter and level of interlukin-6 in experimental animals. Additionally, the antimicrobial activity of the prepared formulations was assessed. The nanoemulsion was considered adequately formed when it had droplets of between 65 and 195 nm. The statistical design proved the important synergistic effect of coconut oil and simvastatin for burn wound management in their synergistic potentiation of wound closure and their anti-inflammatory and antimicrobial effects. The optimum formulation achieved up to a 5.3-fold decrease in the mean burn wound diameter, a 4.25-fold decrease in interleukin-6 levels, and a 6-fold increase in the inhibition zone against Staphylococcus aureus when compared with different control formulations. Therefore, the designed nanoemulsions containing a combination of coconut oil and simvastatin could be considered promising platforms for the treatment of chronic and burn wounds.
Keywords: burns; coconut oil; experimental design; nanoemulsion; simvastatin; wound healing.