Phototherapy has demonstrated positive effects in the treatment of peripheral nerve injury, but there is a need to investigate the dosimetric parameters. Thus, the aim of the present study was to conduct a literature review on the effects of photobiomodulation with the use of low-level laser therapy (LLLT) on the treatment of peripheral nerve injury in experimental models. The databases of PubMed/MEDLINE, SCOPUS, and SPIE Digital Library were searched for articles on the use of LLLT in experimental models of peripheral nerve injury published in English between January 2007 and March 2016. The laser parameter variability was wavelength (632.8 to 980 nm), power (10 to 190 mW), and total energy (0.15 to 90 J) in pulsed or continuous wave and single or multiple points. Eighteen original articles demonstrating the effects of LLLT on the acceleration of functional recovery, morphological aspects as well as the modulation of the expression inflammatory cytokines, and growth factors were selected. LLLT is a viable phototherapeutic modality for the treatment of peripheral nerve injury, demonstrating positive effects on the neuromuscular repair process using either red or infrared light. The majority of studies used a power of up to 50 mW andtotal energy of up to 15 J administered to multiple points. The determination of these parameters is important to the standardization of a LLLT protocol to enhance the regeneration process following a peripheral nerve injury.

Accumulation of iron at sites where neurons degenerate in Parkinson's disease (PD) and Alzheimer's disease (AD) is thought to have a major role in oxidative stress induced process of neurodegeneration. The novel non-toxic lipophilic brain- permeable iron chelators, VK-28 (5- [4- (2- hydroxyethyl) piperazine-1-ylmethyl]- quinoline- 8- ol) and its multi-functional derivative, M-30 (5-[N-methyl-N-propargylaminomethyl]-8-hydroxyquinoline), as well as the main polyphenol constituent of green tea (-)-epigallocatechin-3-gallate (EGCG), which possesses iron metal chelating, radical scavenging and neuroprotective properties, offer potential therapeutic benefits for these diseases. M-30 and EGCG decreased apoptosis of human SH-SY5Y neuroblastoma cells in a neurorescue, serum deprivation model, via multiple protection mechanisms including: reduction of the pro-apoptotic proteins, Bad and Bax, reduction of apoptosis-associated Ser139 phosphorylated H2A.X and inhibition of the cleavage and activation of caspase-3. M-30 and EGCG also promoted morphological changes, resulting in axonal growth-associated protein-43 (GAP-43) implicating neuronal differentiation. Both compounds significantly reduced the levels of cellular holo-amyloid precursor protein (APP) in SH-SY5Y cells. The ability of theses novel iron chelators and EGCG to regulate APP are in line with the presence of an iron-responsive element (IRE) in the 5'-untranslated region (5'UTR) of APP. Also, EGCG reduced the levels of toxic amyloid-beta peptides in CHO cells over-expressing the APP"Swedish"mutation. The diverse molecular mechanisms and cell signaling pathways participating in the neuroprotective/neurorescue and APP regulation/processing actions of M-30 and EGCG, make these multifunctional compounds potential neuroprotective drugs for the treatment of neurodegenerative diseases, such as PD, AD, Huntington's disease and amyotrophic lateral sclerosis.

BACKGROUND:The aim of the study was to determine the effect of different application timings of hyperbaric oxygen treatment (HBO) on nerve regeneration in rats.

MATERIALS AND METHODS:A total of forty 12-week-old female Wistar albino rats were used. The sciatic nerve was transected. The nerve ends were then realigned and repaired using standard microsurgical techniques. Animals were randomly assigned to four groups: 1) No hyperbaric oxygen, sectioned and repaired; 2) HBO started at postoperative first hour, sectioned and repaired; 3) HBO started at postoperative first week, sectioned, and repaired; and 4) HBO started at postoperative second week, sectioned, and repaired. All rats in all groups were evaluated with gait analysis at 8 and 16 weeks postoperatively. Sciatic function index was calculated. Sciatic nerve samples were taken after gait analysis at 16th week. Foreign body reaction, the intensity of the inflammatory cells and types, repair-associated vascular proliferation in the field, axonal vacuolar degeneration of the fibers from the cut line transition density and switching layout, and myelinization density with perineural sheath were evaluated histopathologically.

RESULTS:At the 16th week, group 2 demonstrated the best gait analysis results. Gait analysis was better for group 3 than groups 1 and 4 (P < 0.05). No significant differences were observed among the groups in inflammation (P > 0.05). Fibrosis was statistically less in group 2 than that in other groups (P < 0.05); however, no significant differences were observed among groups 1, 3, and 4 (P > 0.05).

CONCLUSIONS:Our results suggest that initiating HBO early after nerve repair will make a positive impact on recovery.© 2016 Wiley Periodicals, Inc. Microsurgery, 2016.