Provesicular elastic carriers of Simvastatin for enhanced wound healing activity: An in-vitro/in-vivo study

The aim of this study was to prepare and evaluate simvastatin (SIM) loaded elastic provesicular systems for effective topical wound management. SIM provesicles were prepared using the non-ionic surfactant Span 40, cholesterol and three edge activators i.e. Span 80, Tween 80 and sodium cholate. The vesicles revealed high SIM encapsulation efficiency ranging from 87.25 to 98.15%, whereas vesicle sizes ranged from 462.3 to 801.5 nm. Vesicle sizes decreased with increasing the concentration of the edge activator. High negative zeta potential values were observed, revealing good stability of the vesicular formulations. The release of SIM from hydrated provesicular carriers was biphasic in nature. The selected SIM provesicular elastic carrier exerted approximately two-fold increase in the amount of SIM permeated through rat skin, compared to the free drug. Evaluation of wound healing activity of the selected provesicular formulation revealed significant reduction in wound size in rats, fourteen days post-wounding. These results were further confirmed by a significant increase in expression of vascular endothelial growth factor and collagen type I compared to the free drug. These results indicate that provesicular carriers could be a promising drug delivery system for encapsulating SIM and enhancing its wound healing efficacy.