SIRT1 and miR-34a as Potential Plasma Biomarkers in the Acute Phase of Ischemic Stroke.

Stroke is the major cause of disability and mortality worldwide. Identification of molecular biomarkers in the early hours after stroke is important in terms of both diagnostic and therapeutic applications. miR-34a, a highly expressed miRNA, is involved in many pathological mechanisms in the central nervous system. This miRNA targets sirtuin 1 (SIRT1) gene. Here, the efficacy of miR-34a/SIRT1 axis as a potential biomarker in the acute phase of ischemic stroke has been evaluated. 100 patients (in the first 12 hours after ischemic stroke) and 100 healthy subjects were examined. miR-34a expression level was assessed using real-time polymerase chain reaction and SIRT1 level was measured using Enzyme-linked immunosorbent assay. Stroke etiology and infarct size were investigated in the patients. The National Institutes of Health Stroke Scale (NIHSS) was also evaluated. Compared to the healthy controls, ischemic stroke patients showed increased miR-34a expression (P < 0.0001) and decreased SIRT1 levels (P < 0.0001). The levels of miR-34a and SIRT1 showed significant differences among various subtypes of stroke etiology and infarct size. The baseline NIHSS values were correlated negatively with SIRT1 (r=-0.89) and positively with miR-34a (r=0.81). Our results suggested that dysregulation in miR-34a/SIRT1 may be a potential biomarker in occurrence and severity of ischemic stroke.