miR-101-3p improves neuronal morphology and attenuates neuronal apoptosis in ischemic stroke in young mice by downregulating HDAC9.

Objective: MiRNAs play a key role in ischemic stroke (IS). Although miR-101-3p can participate in multiple disease processes, its role and mechanism in IS are not clear. The aim of the present study was to observe the effect of miR-101-3p activation on IS in young mice and the role of HDAC9 in this effect.

Methods: The young mice were first subjected to transient middle cerebral artery occlusion (tMCAO) or sham surgery, and the cerebral infarct area was assessed with 2,3,5-triphenyltetrazolium chloride staining. Meanwhile, the expressions of miR-101-3p and HDAC9 were tested using RT-qPCR or western blot. Besides, neuron morphology and apoptosis were confirmed using Nissl staining and TUNEL staining.

Results: We first verified that miR-101-3p was downregulated and HDAC9 was upregulated in the brain tissue of tMCAO young mice. Moreover, we proved that overexpression of miR-101-3p could improve cerebral infarction, neuronal morphology, and neuronal apoptosis in tMCAO young mice by lowering the expression of HDAC9.

Conclusions: Activation of miR-101-3p can protect against IS in young mice, and its mechanism is relevant to the inhibition of HDAC9. Therefore, miR-101-3p and HDAC9 might be the latent targets for IS therapy.