Influence of miRNA Gene Polymorphism on Recurrence and Age at Onset of Ischemic Stroke in a Chinese Han Population

Identification and preliminary validation of differently expressed genes as candidate biomarkers associated with atherosclerosis

OBJECTIVE

Atherosclerosis (AS) is the primary cause of deadly cardio-cerebro vascular diseases globally. This study aims to explore the key differentially expressed genes (DEGs), potentially serving as predictive biomarkers for AS.

METHODS

Microarray datasets were retrieved from the GEO database for DEGs and DE-miRNAs identification. Then biological function of DEGs were elucidated based on gene ontology (GO) and KEGG pathway enrichment analysis. The protein-protein interaction (PPI) network and DEGs-DE-miRNAs network were constructed, with emphasis on hub DEGs selection and their interconnections. Additionally, receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic precision of hub DEGs for AS. More importantly, an AS Syrian Golden hamster model was established to validate the expression levels of hub DEGs in AS.

RESULTS

A total of 203 DEGs and 10 DE-miRNAs were screened, with six genes were chosen as hub DEGs. These DEGs were significantly enriched in AS-related biological processes and pathways, such as immune and inflammatory response, cellular response to IL-1 and TNF, positive regulation of angiogenesis, Type I diabetes mellitus, Cytokine-cytokine receptor interaction, TLR signaling pathway. Also, these DEGs and DE-miRNAs formed a closely-interacted DE-miRNAs - DEGs - KEGG pathway network. Besides, hub DEGs presented promising diagnostic potential for AS (AUC: 0.781 ∼ 0.887). In addition, the protein expression levels of TNF-α, CXCL8, CCL4, IL-1β, CCL3 and CCR8 were significantly increased in AS group Syrian Golden hamsters.

CONCLUSION

The identified candidate genes TNF, CXCL8, CCL4, IL1B, CCL3 and CCR8 may have the potential to serve as prognostic biomarker in diagnosing AS.

Association between miR-365 polymorphism and ischemic stroke in a Chinese population

Background

Ischemic stroke (IS) represents a major cause of morbidity and mortality across the globe. The aberrant expression of miR-365 has been found to be implicated in a wide array of human diseases, including atherosclerosis and cancer. Studies on single-nucleotide polymorphisms (SNPs) in miRNA genes can help gain insight into the susceptibility to the condition. This study aimed to examine the relationship between miR-365 SNPs and the risk of IS.

Methods

The study recruited 215 IS patients and 220 controls. The SNPscans genotyping was employed to genotype three polymorphic loci (rs121224, rs30230, and rs178553) of miR-365. The relative expression of miR-365 in peripheral blood mononuclear cells of the patients and controls was determined by using real-time quantitative PCR.

Results

The miR-365 rs30230 polymorphism exhibited a significant association with the risk of developing IS (TC vs. CC: adjusted OR = 0.55, 95% CI: 0.33-0.92, P = 0.022; TT vs. CC: adjusted OR = 0.34, 95% CI: 0.14-0.85, P = 0.021; TC +TT vs. CC: adjusted OR = 0.51, 95% CI: 0.31-0.83, P = 0.007; T vs. C: adjusted OR = 0.57, 95% CI: 0.39-0.83, P = 0.004). Haplotype analysis revealed that the C-T-G haplotype was associated with a decreased risk of IS (OR = 0.68, 95% CI: 0.46-1.00, P = 0.047). Furthermore, miR-365 expression was significantly higher in IS patients than in controls (P < 0.001). Interestingly, patients with rs30230 TC or TT genotypes had lower miR-365 levels compared to their counterparts with CC genotypes (P < 0.001).

Conclusions

The miR-365 rs30230 polymorphism might bear an association with IS susceptibility in the Chinese population, and the rs30230 TC/TT genotype might be a protective factor against IS.

miR-122 dysregulation is associated with type 2 diabetes mellitus-induced dyslipidemia and hyperglycemia independently of its rs17669 variant

BACKGROUND

miR-122 is a liver specific micro-RNA that participates in the regulation of carbohydrate and lipid metabolism. The rs17669 variant of miR-122 is positioned at the flanking region of miR-122 and may affect its stability and maturation. Therefore, this study was aimed to investigate the association of the rs17669 polymorphism with the miR-122 circulating level, risk of type 2 diabetes mellitus (T2DM) development, and biochemical parameters in T2DM patients and matched healthy controls.

METHODS AND RESULTS

This study involved 295 subjects (controls: n = 145 and T2DM: n = 150). The rs17669 variant genotyping was done by ARMS-PCR. Serum biochemical parameters including lipid profile, small-dense low density lipoprotein (sdLDL) and glucose were measured by colorimetric kits. Insulin and Glycated hemoglobin (HbA1c) were assayed using ELISA and capillary electrophoresis methods, respectively. miR-122 expression was measured by real-time PCR. There was no significant difference between study groups in terms of allele and genotype distribution (P > 0.05). The rs17669 variant did not have any significant association with miR-122 gene expression and biochemical parameters (P > 0.05). miR-122 expression level in T2DM patients was significantly higher than that in control subjects (5.7 ± 2.4 vs. 1.4 ± 0.78) (P < 0.001). Furthermore, miR-122 fold change had a positive and significant correlation with low-density lipoprotein cholesterol (LDL-C), sdLDL, fasting blood sugar (FBS), and insulin resistance (P < 0.05).

CONCLUSION

It can be concluded that the rs17669 variant of miR-122 is not associated with the miR-122 expression and T2DM-associated serum parameters. Furthermore, it can be suggested that miR-122 dysregulation is involved in T2DM development through inducing dyslipidemia, hyperglycemia, and resistance to insulin.

The prevention of stroke by statins: A meta-analysis

PURPOSE

The objectives of this study were to determine the preventive effects of statins on stroke.

METHODS

The published randomized controlled trials of statins for stroke prevention were searched from PubMed, EMBASE, Cochrane Library, and China Journal databases. We performed the meta-analysis via calculating the odds ratio (OR) and 95% confidence interval (CI) to study the mortality rate, incidence, and recurrence rate of patients with stroke in the prevention group and the control group. Chi-square-based Q test and I2 statistics were performed to test the potential heterogeneity; we conducted the sensitivity analysis to assess the stability of our analysis. Moreover, we performed the Begg and Egger tests to assess the publication bias.

RESULTS

Nine studies were included to perform meta-analysis, which included 15,497 patients (prevention group [n = 4114]; control group [n = 11383]). We found that the statins were not associated with the patients with stroke in mortality rate (OR = 1.00, 95% CI [0.82, 1.23]) and incidence (OR = 0.94, 95% CI [0.46, 1.92]) between the 2 groups. However, there was a significant differences in recurrence rate between the 2 groups (OR = 0.31, 95% CI [0.19, 0.51]).

CONCLUSIONS

Our findings indicated that the statins were associated with the patients with stroke in recurrence rate, but there was no significant correlation with the mortality and morbidity of patients with stroke.

Epigenetics Modifications in Large-Artery Atherosclerosis: A Systematic Review

OBJECTIVES

In recent years, the evidence of the relationship between epigenetics and acute ischemic stroke (AIS) were accumulating, however, the epigenetic characteristics that directs specifically towards the aetiology of large-artery atherosclerosis (LAA) remain ambiguous. The aim of this study was to highlight the overall evidence concerning the epigenetic mechanisms associated with the occurrence of LAA.

MATERIALS AND METHODS

Studies that involve investigations related to epigenetic markers (DNA methylation and RNA modifications) and LAA were retrieved from eleven scientific publication databases. The studies were screened through the pre-set inclusion and exclusion criteria prior to the NOS evaluation.

RESULTS

Eligible studies (n=25) were evaluated. Of which, six reported on DNA methylation and 19 studies assessed RNA modifications (16 on miRNAs, two on lncRNAs, and one study on circRNA). Hypomethylation of MTRNR2L8 and ERα promoters; microRNAs (miR-7-2-3p, miR-16, miR-34a-5p, miR-126, miR-143, miR-200b, miR-223, miR-503, miR-1908, miR-146a rs2910164 C/G, miR-149 rs2292832 T/C, miR-200b rs7549819 T/C, miR-34a rs2666433); lncRNA of ZFAS1; and circRNA of hsa_circRNA_102488 were associated with LAA significantly.

CONCLUSION

Current systematic review highlighted hypomethylation of miRNAs and lncRNA might be the potential biomarkers for LAA.