Influence of miR-1 on Nerve Cell Apoptosis in Rats with Cerebral Stroke via Regulating ERK Signaling Pathway

To explore the effect of mi r‐1 on neuronal apoptosis in rats with stroke through the erk signaling pathway.Methods .Forty male rats (180‐220 g) were selected and randomly divided into the sham, model, mi r‐1 inhibitor, and mi r‐1 mimic groups (10 rats per group) by average body weight.Cerebral ischemia/reperfusion (i/r) models were established using a modified middle cerebral artery wire thrombosis (mcao) method in rats in the model group, mi r‐1 inhibitor group, and mi r‐1 mimic group.After the successful model establishment, the mi r‐1inhibitor group and mi r‐1 mimic group were intravenously injected with mi r‐1 inhibitor and mi r‐1 mimic, respectively, once a day for 3 days.The sham and model groups were given the same dose of normal saline.Ttc staining was applied to detect the cerebral infarct size and calculate the infarct volume.Histopathological changes in the hippocampus of rat brains were observed by he staining.Flow cytometry was used to detect neuronal apoptosis in rat brains.The m rna expressions of mi r‐1, erk1/2, bcl‐2, and bax in rat brain tissues were determined by qrt pcr, and the protein levels of erk1/2, bcl‐2, bax, and caspase‐3 were determined by western blot analysis.Results .Compared with the sham group, the neurological impairment score, cerebral infarct size, and volume of rats in the model group were significantly increased ( p &lt; 0.05).Compared with the model group, the neurological impairment score, cerebral infarct size, and volume were significantly increased in the mi r‐1 mimic group and significantly decreased in the mi r‐1 inhibitor group ( p &lt; 0.05).In the model group, the hippocampal tissue of rats had malaligned cells, neuron cell atrophy became smaller, the intercellular spaces became larger, and vacuoles appeared.Compared with the model group, the mi r‐1 inhibitor group could effectively alleviate the pathological changes in the hippocampus, and the mi r‐1 mimic group could significantly add to the pathological changes in the rat hippocampus.Compared with the sham group, the m rna expression of mi r‐1 and bax in the brain of model rats increased significantly ( p &lt; 0.05), and the m rna expression of erk1/2 decreased significantly; compared with the model group, the mi r‐1 and bax m rna expressions in the brain tissues of rats in the mi r‐1 inhibitor group were significantly decreased, the erk1/2 and bcl‐2 m rna expressions were significantly increased, and the mi r‐1 and bax m rna expressions in the brain tissues of rats in the mi r‐1 inhibitor group were significantly decreased, and the bcl‐2 m rna expression was significantly increased ( p &lt; 0.05).Compared with the sham group, neuronal apoptosis was increased in the brain tissues of rats in the model group and mi r‐1 mimic group.Compared with the model group, neuronal apoptosis was decreased in the brain tissues of rats in the mi r‐1 inhibitor group.Compared with the sham group, the erk1/2 proteins in the model group were significantly decreased, the bcl‐2, bax, and caspase‐3 proteins were significantly increased, and the erk1/2, bcl‐2, bax, and caspase‐3 proteins in the mi r‐1 inhibitor group and mi r‐1 mimic group were significantly increased.Compared with the model group, the protein levels of erk1/2 and bcl‐2 in the mi r‐1 inhibitor group were significantly increased, the proteins of bax and caspase‐3 were significantly decreased, and the protein levels of erk1/2 and bcl‐2 in the mi r‐1 inhibitor group were significantly increased ( p &lt; 0.05).Conclusions .Mi r‐1 can interfere with neuronal apoptosis in rats with stroke through the erk signaling pathway.

Journal: BioMed Research International (2021)
Publication types: Research Article;