Quercetin loaded chitosan tripolyphosphate nanoparticles accelerated cutaneous wound healing in Wistar rats

Previous studies have shown that quercetin on topical application improved cutaneous wound healing in rats, but hydrophobic nature and less skin penetration limits its potential as topical healing agent. Therefore, present study was planned to investigate wound healing potential of chitosan based quercetin nanoparticles. Quercetin loaded nanoparticles were synthesized by ionic gelation method and characterized by various standard techniques. A 2 × 2 cm² square shaped wound was created on the thoraco-lumbar part of rats. Wounded rats were divided into 6 groups namely, gel (20%), blank nanoparticle (0.16%), bulk quercetin (0.3%), quercetin nanoparticles (0.03%), quercetin nanoparticles (0.1%) and quercetin nanoparticles (0.3%) treated groups. Different formulations of quercetin nanoparticles were applied on the wounds for the duration of study and healing tissues were collected on 7th, 14th and 21st day to study various parameters. Quercetin loaded nanoparticles were 361.16 ± 9.72 nm size and spherical in shape. We observed quercetin nanoparticles (0.03%) treatment caused marked reduction in the tumor necrosis factor-alpha, whereas expressions of interleukin 10, vascular endothelial growth factor and transforming growth factor beta1 was increased significantly with treatment. The granulation tissue of quercetin nanoparticles (0.03%) treated group showed better quality healing and maturity as supported by the increased blood vessels density, decreased inflammatory cells, increased number of myofibroblasts, deposition and arrangement of collagen fibers and re-epithelialization. In conclusion, quercetin nanoparticles (0.03%) treatment significantly improved wound healing by modulation of cytokines and growth factors involved in inflammatory and proliferative phases of wound healing.