Plasmatic microRNA as Potential Biomarkers of Multiple Sclerosis: Literature Review.

There is ongoing research with the goal of finding precise and sensitive biomarkers of multiple sclerosis (MS). Recently, researchers have paid particular attention to small, non-encoding, single stranded endogenous microRNA molecules (miR, miRNA). At first these molecules were thought to be found only within the cell. Today it is known, however, that they can also be found in the extracellular spaces (plasma, serum, saliva, urine, tears, sweat, milk, sperm and amniotic fluid, among others). It has been established that extracellular miRNA perform a wide spectrum of functions, such as transmitting signals between cells, modulating processes involved in angiogenesis, neurogenesis, proliferation or apoptosis. Given the high stability of these small molecules in the extracellular compartment (plasma), their tissue specificity and strong ties with pathological processes underlying multiple sclerosis, miRNA seem to be a good target for researchers trying to discover diseases' new markers. Determining an accurate miRNA expression profile in MS and correlating it with the gene profile may lead to the discovery of new pathophysiological processes. Demonstrating that changes in the composition and concentration of extracellular miRNA may in some cases correlate with certain aspects of the underlying disease (such as its severity) could lead to their use as biomarkers of MS. Further research is needed.