Association of miR-122, miR-124 miR-126 and miR-143 gene polymorphisms with ischemic stroke in the northern Chinese Han population

Regulatory miR-SNP rs4636297A > G in miR-126 is linked to increased risk of rigidity feature in patients with Parkinson's disease

INTRODUCTION

A growing body of strong evidence shows that the dysfunction of miRNAs plays key roles in the development and progression of Parkinson's disease (PD), however, little data has been reported on the association of their SNPs with PD susceptibility. In this study, we investigated the association of regulatory miR-SNP rs4636297A > G with a functional effect on the expression of miRNA-126, as a key dysregulated miRNA in the PD, with the susceptibility and clinical features of the PD.

METHODS AND MATERIALS

In current study, we included a population consisting of 120 patients with PD and 120 clinically healthy individuals, and their blood samples were taken. After extracting the DNAs, the genotyping of the miR-SNP rs4636297A > G was done through RFLP-PCR technique. Finally, the association of this SNP with the risk and clinical features of PD was determined.

RESULTS

Although the results showed that the two groups did not differ significantly in terms of allelic and genotype frequencies, it was clinically found that individuals with genotypes carrying the minor allele G (AG and GG genotypes) of the miR-SNP rs4636297A > G had an increased risk of developing rigidity feature in the PD compared to its homozygous major AA genotype (GG genotype; OR = 5.14, p = 0.038 & GA genotype; OR = 4.32, p = 0.032).

CONCLUSION

We report for the first time a significant association of functional regulatory SNP rs4636297A > G in the miR-126 with the Parkinson's clinicopathology. Therefore, this miR-SNP can have a potential predictive biomarker capacity for rigidity in PD, although this hypothesis needs further investigation in the future.

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.

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.

Circulating Exosomes and Their Role in Stroke

Stroke is an acute neurologic disorder which can be life-threatening if left untreated or diagnosed late. Various detecting techniques including neurologic imaging of the brain by computed tomography or magnetic resonance imaging can facilitate diagnosis of stroke. However, according to the recent advances in molecular detection techniques, new diagnostic and prognostic markers have emerged. Exosomes as an extra cellar particle are one of these markers which can have useful diagnostic, prognostic, and even therapeutic impact after stroke. We have previously discussed the role of exosomes in cardiovascular disease and in the present review we focus on the most common cerebrovascular disease. The aim of the present review is summarizing the recent diagnostic role of exosomes which are specifically secreted during a stroke and can guide clinicians to better diagnosis of stroke.

Association between functional polymorphisms in the flanking region of miR-143/145 and risk of papillary thyroid carcinoma: A case-control study

MiR-143 and miR-145 were down-regulated in papillary thyroid carcinoma (PTC) involving in cell proliferation, apoptosis, migration, invasion, and epithelial to mesenchymal transition. In this study, we aimed to investigate the association between 2 functional polymorphisms (ie, rs4705342 and rs353292) in the flanking region of miR-143/145 and risk of PTC.A case-control study including 316 PTC patients and 347 controls was performed. The rs4705342 and rs353292 were genotyped by using the TaqMan allelic discrimination. The results were confirmed by DNA sequencing.For the rs4705342, a reduced risk of PTC was observed in heterozygous comparison, dominant genetic model and allele comparison (CC vs TT: adjusted OR = 0.37, 95% CI = 0.19-0.74, P = .003; CT/CC vs TT: adjusted OR = 0.64, 95% CI = 0.47-0.87, P = .005; C vs T: adjusted OR = 0.66, 95% CI = 0.52-0.85, P = .001, respectively). No significant difference was found in the genotypic distributions of the rs353292 between cases and controls.These findings indicate that the rs4705342 in the flanking region of miR-143/145 may be a protective factor against the occurrence of PTC. Further study is therefore required to investigate the correlation between the genotype and V-raf murine sarcoma viral oncogene homolog B1 V600E, rat sarcoma viral oncogene homolog mutations, rearranged in transformation/PTC1 and rearranged in transformation/PTC3.

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

Polymorphisms in microRNAs (miRNAs) are associated with ischemic stroke occurrence and traditional risk factors for ischemic stroke such as atherosclerosis, hypertension, hyperlipidemia, and diabetes. However, few studies have examined recurrent ischemic stroke as an outcome. Thus, the aim of our study was to examine association of miRNA gene polymorphisms (namely, miR-126 rs4636297, miR-149 rs2292832, miR-124 rs531564, miR-499 rs3746444, miR-143 rs12655723, and miR-122 rs17669) with recurrence of ischemic stroke. miRNA gene polymorphisms were genotyped using the polymerase chain reaction-ligation detection reaction (PCR-LDR) method in 657 patients with ischemic stroke. Association of miRNA polymorphisms with prognosis outcomes was examined by the Kaplan-Meier method, log-rank test, and Cox proportional hazards models. miR-122 rs17669 was significantly associated with recurrence risk of ischemic stroke under the recessive model. Cox regression analysis showed that the CC genotype of rs17669 was associated with an increased risk of 1.9-fold for stroke recurrence (hazard ratio = 1.879; 95% confidence interval = 1.182-2.985; P = 0.008). Further, this effect was more evident among the non-drinker and male subgroups. We found no difference in risk of recurrent ischemic stroke among the other five miRNA polymorphisms. Furthermore, we identified a significant association between the miR-149 rs2292832 polymorphism and age at onset of first-ever stroke. Altogether, miR-122 rs17669 is a significant predictor for the risk of recurrent stroke, independent of traditional risk factors.