In vitro and in vivo efficacy evaluation of new self-assembling curcumin loaded nanohyaluronan-glycerosomes on wound restoring in health and diabetic rats

In this study the wound healing efficacy of new self-assembling curcumin loaded nanohyaluronan-glycerosomes has been tested in healthy and diabetic rats. Curcumin was loaded in nanohyaluronan-liposomes and -glycerosomes, special vesicles obtained mixing curcumin, hyaluronan nanohydrogel and soy lecithin. Curcumin loaded liposomes and glycerosomes were also prepared, characterized and tested as references. The physico-chemical (size and size distribution, surface charge and morphology), and technological (entrapment efficiency, stability over time and skin delivery) characteristics and biological performances (safety, ability to protect in vitro cells from oxidative damage) of prepared formulations were measured. Finally, they were daily applied to skin wounds of healthy or diabetic rats. The animal skin was excided and analysed at days 3, 7 and 14. The macroscopic observation underlined the higher ability of curcumin loaded nanohyaluronan-glycerosomes to improve wound healing in diabetic rats, already on day 3 up to day 14 (p < 0.05). Histopathological analysis confirmed an accelerated re-epithelization in healthy rats, while increased angiogenesis in diabetic ones. The superior therapeutic efficacy of curcumin loaded nanohyaluronan-glycerosomes compared to other formulations can be related to their enhanced ability to deliver higher curcumin concentrations at the wound site due to a synergistic effect of glycerol, hyaluronan nanohydrogel and lecithin.