Citation

Osier N, McGreevy E, Pham L, Puccio A, Ren D, Conley YP, Alexander S, Dixon CE. Int. J. Mol. Sci. 2018; 19(5): e19051539.

Affiliation

V.A. Pittsburgh Healthcare System, Pittsburgh, PA 15240, USA. dixoec@upmc.edu.

Copyright

(Copyright © 2018, Molecular Diversity Preservation International)

DOI

10.3390/ijms19051539

PMID

29786658

Abstract

Melatonin (MEL) is a hormone that is produced in the brain and is known to bind to MEL-specific receptors on neuronal membranes in several brain regions. MEL's documented neuroprotective properties, low toxicity, and ability to cross the blood-brain-barrier have led to its evaluation for patients with traumatic brain injury (TBI), a condition for which there are currently no Food and Drug Administration (FDA)-approved therapies. The purpose of this manuscript is to summarize the evidence surrounding the use of melatonin after TBI, as well as identify existing gaps and future directions. To address this aim, a search of the literature was conducted using Pubmed, Google Scholar, and the Cochrane Database. In total, 239 unique articles were screened, and the 22 preclinical studies that met the a priori inclusion/exclusion criteria were summarized, including the study aims, sample (size, groups, species, strain, sex, age/weight), TBI model, therapeutic details (preparation, dose, route, duration), key findings, and conclusions. The evidence from these 22 studies was analyzed to draw comparisons across studies, identify remaining gaps, and suggest future directions. Taken together, the published evidence suggests that MEL has neuroprotective properties via a number of mechanisms with few toxic effects reported. Notably, available evidence is largely based on data from adult male rats and, to a lesser extent, mice. Few studies collected data beyond a few days of the initial injury, necessitating additional longer-term studies. Other future directions include diversification of samples to include female animals, pediatric and geriatric animals, and transgenic strains.

Language: en

Keywords

melatonin; neurotrauma; preclinical; review; therapy; traumatic brain injury (TBI)