The significance of low plasma miR-335 level in patients with acute cerebral infarction may be associated with the loss of control of CALM 1 expression

Calcium overload, mediated by calmodulin (CaM), plays an important role in ischemia/reperfusion injury during acute ischemic brain damage. However, the regulation of CaM expression in cerebral ischemia is still not fully addressed. This study showed that the levels of plasma miR-335 were significantly down-regulated in 152 patients with acute cerebral infarction (0.60 ± 0.31) compared to 136 age-matched healthy controls (1.16 ± 0.30) (P < 0.01). Moreover, the levels negatively correlated with the National Institutes of Health Stroke Scale (NIHSS) scores in acute cerebral infarction patients (r = -0.680; P < 0.01). Transfection of miR-335 mimics and inhibitors inhibited CALM1 mRNA and CaM protein expressions in HUVECs. This study suggests that miR-335 is an important biomarker of acute cerebral infarction, and which functions are through regulating the expression of the CALM1 gene during acute ischemic brain injury. Our findings highlighted the potential of miR-335 as a target to develop agents to treat acute cerebral infarction.