MicroRNAs (miRNAs) are small non-coding RNAs approximately 22
nucleotides in length that play a pivotal role in post-transcriptional
gene regulation by binding to complementary sites in the 3’-untranslated
region of messenger RNAs. In the past decade, their role in several
human diseases, from cancer to cardiovascular disease, has been
established by a wealth of evidence. Stroke is responsible for 10% of
deaths worldwide and is one of the leading causes of disability. MiRNAs
are involved in stroke risk factors including hypertension,
atherosclerosis, atrial fibrillation, diabetes and dyslipidemia. The
role of miRNAs in the pathophysiology of stroke has been the subject of
more recent investigations. Animal studies, which dominate the field,
have demonstrated the differential expression of miRNAs in brain and
blood following ischemic or hemorrhagic insult and the potential use of
miRNA antagonists to reduce focal cerebral damage. In particular,
antagomirs to miR-145, -497, -181a, -1 and let-7f have been found to be
neuroprotective in vivo. The discovery of circulating miRNAs in
peripheral blood, which are unexpectedly stable, has allowed the recent
completion of several studies in human stroke patients that have
confirmed the differential expression of specific miRNAs following
stroke and have addressed their potential use as diagnostic and
prognostic markers. With miRNA research in stroke still in its infancy,
it is anticipated that in the next few years significant discoveries
that may have important therapeutic implications will emerge
