The dysregulation expression of microRNAs (miRNAs) including miR-144, has been widely documented in TBI. However, little is known about the potential roles of miR-144 in the pathogenesis of TBI. In this study, we investigated the potential effects of miR-144 on cognitive function in vivo and in vitro. The results indicated that inhibition of miR-144 conferred a better neurological outcome after TBI in vivo, as evidenced by reduced lesion volume, alleviated brain edema and increased mNSS, of particular importance, improved cognitive deficits. In vitro, miR-144 knockdown protected neuron against Glu-induced injury, by enhancing cell viability, suppressing LDH release and caspase-3 activity, and reducing cognitive-related proteins levels. However, overexpression of miR-144 in vivo and in vitro showed the opposite effects. To further explore the molecular mechanisms underlying miR-144-induced cognitive dysfunctions, we found a significant inverse correlation between miR-144 and ADAM10 expression. Moreover, the direct interaction between miR-144 and ADAM10 3'-UTR was identified by dual-luciferase reporter assay. Also, we found miR-144 negatively regulated ADAM10 protein expression. Additionally, ADAM10 could modulate β-amyloid formation involved in cognitive deficits. Notably, ADAM10 knockdown by siRNA apparently abrogated miR-144 inhibitor-mediated neuroprotection. Taken together, these findings demonstrated that elevated miR-144 promoted cognitive impairments induced by β-amyloid accumulation post-TBI through suppressing of ADAM10 expression.
Keywords: ADAM10; TBI; cognitive impairment; miR-144; β-amyloid.