Single Dose of N-Acetylcysteine in Local Anesthesia Increases Expression of HIF1α, MAPK1, TGFβ1 and Growth Factors in Rat Wound Healing

Abstract

In this study, we aimed to investigate the influence of N-acetylcysteine (NAC) on the gene expression profile, neoangiogenesis, neutrophils and macrophages in a rat model of incisional wounds. Before creating wounds on the backs of 24 Sprague–Dawley rats, intradermal injections were made. Lidocaine–epinephrin solutions were supplemented with 0.015%, 0.03% or 0.045% solutions of NAC, or nothing (control group). Scars were harvested on the 3rd, 7th, 14th and 60th day post-surgery. We performed immunohistochemical staining in order to visualize macrophages (anti-CD68), neutrophils (anti-MPO) and newly formed blood vessels (anti-CD31). Additionally, RT-qPCR was used to measure the relative expression of 88 genes involved in the wound healing process. On the 14th day, the number of cells stained with anti-CD68 and anti-CD31 antibodies was significantly larger in the tissues treated with 0.03% NAC compared with the control. Among the selected genes, 52 were upregulated and six were downregulated at different time points. Interestingly, NAC exerted a significant effect on the expression of 45 genes 60 days after its administration. In summation, a 0.03% NAC addition to the pre-incisional anesthetic solution improves neovasculature and increases the macrophages’ concentration at the wound site on the 14th day, as well as altering the expression of numerous genes that are responsible for the regenerative processes.

Pre-Incisional and Multiple Intradermal Injection of N-Acetylcysteine Slightly Improves Incisional Wound Healing in an Animal Model

“…This may lead to the potential exacerbation of the wound. This contradicts our previously published findings [9], which showed that a single dose of NAC at any concentration had no significant impact on any of the assessed histological categories at the same time points. This further supports the claim of the superiority of a single dose of NAC over multiple doses.…”

“…Promising effects and a lack of substantial side effects encouraged us to explore whether an extension of the therapy from pre-incision to the early phase of wound healing may turn out to be even more fruitful. Recently, we showed that a single dose of NAC applied after the creation of a wound produced slightly slimmer scars with improved histology [9] followed by long-term (over a 60 day observation period) shifts in the gene expression of crucial targets for wound healing and remodeling [10]. Notably, the HIF1alpha pathway was pronouncedly expressed at all timepoints, which is consistent with the findings of other authors, and may be the basis of NAC efficiency in improving wound healing [11,12].…”

“…The GRI decreased by 1.61 compared to the control at day 60 post-op, whereas in our previous study it decreased by only 0.13, and the MRI decreased by 2.75 compared to 0.14 previously. Interestingly, the epidermal thickness at day 60 post-op also decreased by 1.27 µm (p > 0.99), whereas in the single-dose study it increased by 0.3 µm [9]. As such, it can be said that applying multiple doses of NAC to wounds is not only not superior to the single-dose method, but in the case of the 0.03% NAC dose seems to be disadvantageous in terms of improving histomorphology.…”

“…The pleiotropic effect and universal properties of NAC have been also utilized in wound healing [6][7][8]. Our previous studies concern a unique model of the pre-incisional administration of NAC to the future wound bed of a surgical wound, as an additive to local anesthesia [9,10]. Promising effects and a lack of substantial side effects encouraged us to explore whether an extension of the therapy from pre-incision to the early phase of wound healing may turn out to be even more fruitful.…”

Graphene Oxide/Gelatin Nanofibrous Scaffolds Loaded with N-Acetyl Cysteine for Promoting Wound Healing

“…Progressive fibrosis during wound healing causes scarring, characterized by excessive extracellular matrix deposition and overexpression of fibrosis-related genes. Paskal et al 50 revealed that NAC dysregulated the expressions of numerous genes associated with scar formation and improved neovascularization. The present study revealed that NAC significantly downregulated the expression of mRNA for fibrosis-related genes ( Figure 7 ).…”