Objective To investigate whether microRNA(miR)-199a-5p regulates blood-brain barrier(BBB)integrity through PI3K/Akt pathway after cerebral ischemia.Methods A permanent middle cerebral artery occlusion(MCAO)model was established in SPF adult male SD rats.Totally 48 rats were randomly divided into sham group(n=12),model group(n=12),MCAO+miR-199a-5p group(n=12),and MCAO+miR-199a-5p negative control group(n=12).The Ludmila Bellayev 12 point score was used to evaluate the neurobehavioral performance of rats;The integrity of the BBB after ischemia stroke was detected through Evans blue staining;Immunofluorescent staining was used to determine apoptosis after cerebral ischemia;Western blotting technology was used to detect the protein expression of claudin-5,phosphatidylinositol-3 kinase regulatory subunit 2(PIK3R2),p-Akt,Akt,and vascular endothelial growth factor(VEGF)-A;Real-time PCR was used to investigate the expression levels of miR-199a-5p,claudin-5,and VEGF-A in the ischemic penumbra and infarcted area of the brain.Results The result showed that miR-199a-5p mimic intervention improved proprioception and motor ability in MCAO rats.MiR-199a-5p mimic reduced the expression of PIK3R2 following ischemia stroke,activated the Akt signaling pathway,and increased the expression of claudin-5 and VEGF-A in the ischemic penumbra.In addition,miR-199a-5p alleviated inflammation after cerebral ischemia.MiR-199a-5p mimic reduced BBB permeability and reduced neuronal apoptosis after cerebral ischemia.Conclusion MiR-199a-5p can reduce the expression of PIK3R2 following ischemic stroke,activate the Akt signaling pathway,reduce the expression of inflammatory cytokines,and alleviate the damage to the blood-brain barrier.
维普
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