Single Dose of N-Acetylcysteine in Local Anesthesia Increases Expression of HIF1α, MAPK1, TGFß1 and Growth Factors in Rat Wound Healing.

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.

N-Acetylcysteine Added to Local Anesthesia Reduces Scar Area and Width in Early Wound Healing-An Animal Model Study.

The aim of the study was to evaluate if a pre-incisional N-acetylcysteine (NAC) treatment altered the process of wound healing in a rat model. The dorsal skin of 24 Sprague-Dawley rats was incised in six locations. Before the incisions were made, skin was injected either with lidocaine and epinephrine (one side) or with these agents supplemented with 0.015%, 0.03%, or 0.045% NAC (contralaterally). Photographic documentation of the wound healing process was made at 11 time points. Rats were sacrificed 3, 7, 14, or 60 days after incision to excise scars for histological analysis. They included: Abramov scale scoring, histomorphometry analysis, and collagen fiber arrangement assessment. Skin pretreated with 0.03% NAC produced the shortest scars at all analyzed time points, though this result was statistically insignificant. At this NAC concentration the scars had smaller areas on the third day and were narrower on the day 4 compared with all the other groups (p < 0.05). On day 7, at the same concentration of NAC, the scars had a higher superficial concentration index (p = 0.03) and larger dermal proliferation area (p = 0.04). NAC addition to pre-incisional anesthetic solution decreased wound size and width at an early stage of scar formation at all concentrations; however, with optimal results at 0.03% concentration.

Polyethylene Glycol: The Future of Posttraumatic Nerve Repair? Systemic Review.

Peripheral nerve injury is a common posttraumatic complication. The precise surgical repair of nerve lesion does not always guarantee satisfactory motor and sensory function recovery. Therefore, enhancement of the regeneration process is a subject of many research strategies. It is believed that polyethylene glycol (PEG) mediates axolemmal fusion, thus enabling the direct restoration of axon continuity. It also inhibits Wallerian degeneration and recovers nerve conduction. This systemic review, performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, describes and summarizes published studies on PEG treatment efficiency in various nerve injury types and repair techniques. Sixteen original experimental studies in animal models and one in humans were analyzed. PEG treatment superiority was reported in almost all experiments (based on favorable electrophysiological, histological, or behavioral results). To date, only one study attempted to transfer the procedure into the clinical phase. However, some technical aspects, e.g., the maximal delay between trauma and successful treatment, await determination. PEG therapy is a promising prospect that may improve the surgical treatment of peripheral nerve injuries in the clinical practice.