The study was focus on in vivo study of cotton gauze fabric coated with quercetin for wound healing application. The fabric was characterized the coated of quercetin on the fabric fibers by SEM and EDS graph. The bandage was tested the antimicrobial activity by the MIC assay on S. aureus. To test for the durability, the bandage was dissolved in the nitric acid and measured UV-vis at 625nm. The bandages were tested on mice wound healing model. The extracted specimens were sectioned for histological analysis by HE and MT. The SEM results and EDS graph showed the well-coated of quercetin on the fabric fibers. Moreover, the MIC assay depicted the antimicrobial activity of the bandage; followed by the high durability of bandages as result in the release in nitric acid. The histological analysis illustrated the anti-oxidation property and promoted the wound healing process by enhance the formation of neo-angiogenesis.
The aim of wound repair is to attain tissue integrity and homeostasis 26. The healing process involves four phases: hemostasis, inflammation, proliferation and remodeling. For decades, the perfect aesthetic healing of cutaneous wounds has been attempted by using the pharmacological intervention in the healing mechanism. Agents that can check the infection, speed up the healing, favor cell proliferation and matrix deposition, promote reepithelization, cause less or no scar formation, stability, cost effective are considered as ideal agents 26. This is the reason for using quercetin, a flavonoid, for the wound healing studies was based on its properties: antioxidant 16,20,25, anti-microbial 27,28, anti-inflammatory 29-36, which are needed for optimum the wound healing.
The wound contraction is the process that cells moving from healthy skin to the wound to close the denuded area and helping in limiting the amount of granulation tissue that result in decreasing healing time 37. In the study, measurement of wound contraction, which is measure by the percentage of wound closure, is necessary to determine the process of wound healing. The Sample bandages show significantly the promoted wound closure, as compared to the Control bandages. Wound contraction can be occurred by the activity of myofibroblasts in the progress of wound healing 38. Moreover, Mostafa et al. study showed that the quercetin can associate with enhanced myofibroblast activity and increase epithelial cell growth 39. Therefore, the study shows the beneficial effect of quercetin in accelerating wound contraction and healing.
To evaluate the quality of grossly healed wound, histological analysis was applied to figure out whether the used treatment materialized the proposed effects that it has to produce. Histological evaluation involves morphogenic evaluation of re-epithelialization, maturity of granulation tissues, fibroblast proliferation, collagen deposition, inflammation and angiogenesis. The HE stained sections of Sample bandages, particularly, showed decreased of inflammation-mediating cells, as compared to Control bandages. This shows the anti-inflammation properties of quercetin. Additionally, the sectioning results of Sample bandages evidently showed good quality of fibroblast proliferation and significantly collagen deposition, as compared to Control one reveals that Sample bandages might have induced migration and proliferation of fibroblasts. The results also reveal that they might have induced migration and proliferation of keratinocytes base on the presence of regenerated mature epithelium layer. There have been studies also shown that quercetin is an effective chemical that cultured human skin fibroblasts, keratinocytes and endothelial cells can be protected from a protracted oxidative wound 40.
Collagen fibers are the major components of the extracellular matrix produced by fibroblasts, which take responsibility for the tensile resistance and also play an important role in homeostasis and epithelization 26,41. To evaluate a healthy and firm skin, observation of new collagen fiber synthesis is needed, which collagen account for about 70% of the skin weight 42. Furthermore, collagen fibers have also been reported that they associated with the tensile resistance 41. The study shows the increased proliferation of fibroblasts by Sample bandage group might resulted to the increasing collagen deposition of the wound, which is well-evidenced in HE and MT stained sections. The dark blue and light blue color indicates thick and thin collagen fibers which are observed during the later stages and earlier stages of the healing process, respectively, which are similar as the picrosirius red stained sections 43,44. In the study, the dark blue color collagen fibers observed in Sample bandage group was higher than Control group. This reveals that Sample bandages are more towards maturity.
Reactive oxygen species (ROS) occurs post-cutaneous wound, which may cause damage to the healing process and induce apoptosis 45. Low and normal levels of ROS have a good effect for the wound repair and signal transduction for re-epithelialization and proliferation of cells such as the collagenase activity and the epidermal growth factor. On the other hand, high levels of ROS can cause the oxidative stress leading to damage intercellular macromolecules. Therefore, controlling oxidative stress and inflammation response is important during the wound healing process that result in using antioxidants agents as an effective therapeutic approach in wound healing 46. Quercetin is a scavenger of ROS and reactive nitrogen species (RNS) includingsuperoxide anion radical (O2•-), nitric oxide (NO) and peroxynitrite anion (ONOO-) due to its properties 47. The results show that Sample bandages might be more effective antioxidant as compared to Control bandages where the wound was significantly improved healing process and protect tissue from oxidative damage due to the free radical scavenging properties 18,25.