Histological and Immunohistochemical Evaluation of Silver Nanoparticle-Mediated Wound Healing in Rabbits

Silver nanoparticles (AgNPs) have been explored for their antimicrobial properties and potential in wound healing applications. This study investigates the effect of AgNPs on wound healing in a rabbit model. AgNPs were synthesized using a green synthesis approach and characterized by TEM and UV-Vis spectroscopy. Excisional wounds penetrating through the full depth of the skin were surgically induced on the ear of 15 New Zealand White rabbits. The specimens were categorized into 3 groups: control (saline), AgNP-low (0.1 mg/mL), and AgNP-high (1 mg/mL). Wound dressings containing the respective treatments were applied daily. The dimensions of the wounds were assessed at four time points: immediately after wound creation (day 0) and on the 3rd, 7th, and 14th days post -injury. Histological analysis and immunohistochemical staining for collagen I and III were performed on wound tissue samples. AgNPs were successfully synthesized, with an average size of 15 nm. Wound closure in the groups treated with AgNP was noticeably quicker when contrasted with the control group. On day 14, the AgNP-high group showed the highest percentage of wound closure (95.2 +/- 2.1%), followed by the AgNP-low group (88.7 +/- 3.5%) and control (76.4 +/- 4.2%). Histological analysis revealed enhanced reepithelialization, collagen deposition, and neovascularization in the AgNP-treated groups. Immunohistochemical staining demonstrated increased manifestation of collagen I and III in the AgNP groups. The use of AgNPs in a rabbit wound healing model demonstrated significant improvements across multiple parameters, including expedited wound closure, more efficient re-epithelialization, and a notable increase in collagen synthesis and deposition. This evidence implies that AgNPs have the potential to be used as a medicinal aid for enhanced wound healing. Additional research is required to clarify the fundamental processes and optimize the AgNP formulation for clinical applications.