N-acetylcysteine (NAC) Addition To Anaesthetic Solution Decreases Wound Size And Promotes Wound Healing And Activation Of Hif1-alpha And Growth Factors - An Animal Model Study.
Wiktor Paskal, MD, PhD1, Adriana Paskal, MD1, Piotr Pietruski, MD, PhD2, Albert Stachura1, Kacper Pelka, MD1, Michal Kopka1, Pawel Wlodarski, MD, DMD, PhD1.
1Medical University of Warsaw, Department of Methodology, Laboratory of Centre for Preclinical Research, Warsaw, Poland, 2Centre for Postgraduate Education, Department of Plastic Surgery, Warsaw, Poland.
PURPOSE: N-acetylcysteine (NAC) is known for its direct and indirect anti-oxidative effects, while the chronic inflammation is a well-recognised factor impairing wound healing. The aim of the study was to evaluate if a pre-incision NAC injection alters the process of wound formation.
METHODS: The study was conducted according to ARRIVE guidelines. Each of 24 Sprague-Dawley rats had 2 rows of 3 incisions each planned on the dorsal side. In the first row (randomly chosen), injections with lidocaine and epinephrine solution were made (control). In the second row injections contained lidocaine, epinephrine and an addition of NAC in three different concentrations (0,015%, 0,03% and 0,045%). 11 timepoints photographic documentation of wounds was performed. Rats were sacrificed (6/timepoint) on the 3rd, 7th, 14th and 60th day after the wound creation. Then, scars/wounds were excised and preserved for histological and gene expression analyses. RT-qPCR included 94 targets related to wound healing process. Histological morphometric assessment included measurements of various parameters (e.g. width, depth, dermal proliferation area, contraction indexes). Photographic documentation underwent planimetric measurements (wound area, length, width) with ImageJ 1.48v. Mann-Whitney U and ANOVA Kruskal-Wallis tests were used for data statistical analysis.
RESULTS: Photographic analysis showed wounds treated with 0,03% NAC concentration to have smaller wound lengths at all time points as compared with other groups, though statistically insignificantly. Also, scars pretreated with NAC solutions had significantly smaller area on the 3rdday and were narrower on the 4thday compared with all the other groups (p<0.05). We also showed that wounds pretreated with 0,03% NAC had a higher superficial concentration index (SCI) (p=0.03) and a larger dermal proliferation area (DPA) (p=0.04) in histological morphometric measurements on the day 7. Tissue samples treated with NAC showed higher expression of numerous genes vs control group (Figure attached). Upregulation was observed in tissue growth factors (FGF2, FGF10, IGF1, IGF2), selected cytokines and chemokines (TNF, IL1A, IL1B, TGF-B2, IL-10, ELANE), cell adhesion molecules (CDH1, ITA5) and remodeling factors (MMP2, CSK) (p<0,05). Constant upregulation of HIF1-alpha was observed at all timepoints (P<0,05).
CONCLUSION: NAC addition to pre-incisional anesthetic solution decreases wound size and width at an early stage of scar formation, acting as an activator of growth factors and cytokines involved in wound healing. Optimal results have been observed for the 0,03% NAC concentration. Conclusions are based on molecular, microscopic and macroscopic evidence.
Back to 2020 Abstracts