Role of miR-211 in a PC12 cell model of Alzheimer's disease via regulation of neurogenin 2.

NEW FINDINGS: What is the central question of this study? What is the mechanism of miR-211 in an Alzheimer's disease cell model? What is the main finding and its importance? miR-211 was upregulated in an Alzheimer's disease cell model. It targeted neurogenin 2, reduced the activation of the phosphoinositide 3-kinase-Akt signalling pathway, inhibited the proliferation of the Alzheimer's disease cell model and promoted apoptosis. ABSTRACT: MicroRNAs (miRs) are aberrantly expressed in Alzheimer's disease (AD) patients. This study was intended to investigate the effect of miR-211 on an AD cell model and the involvement of neurogenin 2 (Ngn2). The appropriate dose and time for the effect of Aß1-42 on PC12 cells were determined to establish an AD cell model. An effect of miR-211 expression on cell viability, proliferation and apoptosis was detected after cell transfection. Online prediction and a dual luciferase reporter gene assay were utilized to confirm the binding sequence of miR-211 and Ngn2. qRT-PCR and western blot analysis were applied to measure Ngn2 expression. A gain and loss of function assay of miR-211 and Ngn2 was performed, and activation of the phosphoinositide 3-kinase (PI3K)-Akt signaling pathway was detected. The AD cell model was induced by Aß1-42 treatment. miR-211 expression was significantly enhanced after miR-211 transfection, leading to suppressed proliferation and promotion of apoptosis in Aß1-42 -treated PC12 cells. In addition, miR-211 could downregulate Ngn2 mRNA and protein expression, while overexpression of Ngn2 could reverse the effects of miR-211 on Aß1-42 -treated PC12 cells and significantly enhance the phosphorylated Akt and PI3K protein levels. miR-211 could inhibit growth of PC12 cells by suppressing Ngn2 expression and inactivating the PI3K-Akt signalling pathway.

A Correlational Study on Cerebral Microbleeds and Carotid Atherosclerosis in Patients with Ischemic Stroke.

PURPOSE: This study aimed to investigate the correlation between cerebral microbleeds and carotid atherosclerosis in patients with ischemic stroke. SUBJECTS AND METHODS: Patients with ischemic stroke treated in a hospital in China from 2016 to 2017 were enrolled in the study. Based on the results from susceptibility-weighted imaging, the patients were divided into cerebral microbleed and noncerebral microbleed groups. The degree of carotid atherosclerosis was assessed with carotid intima-media thickness (CIMB) and Crouse score of carotid plaque. The details of patients' demographic information, cerebrovascular disease-related risk factors, carotid atherosclerosis indices, cerebral microbleed distribution, and grading were recorded, compared, and analyzed. RESULTS: Logistic regression analysis of the 198 patients showed that CIMB and Crouse score were significantly correlated with the occurrence of cerebral microbleeds. The CIMB thickening group (P = .03) and the plaque group (P = .01) were more susceptible to cerebral microbleeds. In the distribution of cerebral microbleed sites, Crouse scores were the highest in the mixed group and showed a statistically significant difference (P < .01). As the degree of carotid atherosclerosis increased, the average number of cerebral microbleeds also increased (P < .01). The receiver operating characteristic curve analysis of the carotid atherosclerosis indices showed a statistically significant difference. The CIMB value combined with the Crouse score was the best indicator (P < .01). CONCLUSION: In patients with ischemic stroke, cerebral microbleeds are closely related to carotid atherosclerosis. Active control of carotid atherosclerosis is important to prevent cerebral microbleeds in patients with ischemic stroke.