Spinal Cord Injury: A Study Protocol for a Systematic Review and Meta-analysis of microRNA Alterations

Spinal cord injury (SCI) is a condition often resulting in life-long disability, high rehabilitation costs, lost wages, and reduced quality of life. Clinical trials have been hampered in part by a lack of poor diagnostic and prognostic markers of injury severity and neurologic recovery. Furthermore, while many therapies have shown promise in preclinical animal models, there are currently no neurorestorative treatments for SCI. The development of objective biomarkers and novel therapies for SCI represent urgent unmet clinical needs. Biological markers of SCI that objectively stratify the severity of cord damage could greatly expand the depth and scope of clinical trials and represent targets for the development of novel therapies for acute SCI. MicroRNAs (miRNAs) represent promising candidates both as informative molecules of injury severity and recovery, and as therapeutic targets. miRNAs are small, stable, regulatory RNA molecules that are often tissue-specific and evolutionarily conserved across species. miRNAs could represent powerful predictors of pathology, particularly with respect to neurologic disorders. There is great heterogeneity in the current literature describing miRNA changes after SCI with respect to animal species, SCI model, miRNA detection technology, and normalization strategies. Here, we present a protocol to perform a systematic review and meta-analysis to investigate the conserved inter- and intra-species miRNA changes that occur post-SCI and provide a comprehensive resource for the SCI community.