The research of ion channel-related gene polymorphisms with atrial fibrillation in the Chinese Han population

Risk factors and SCN5A-H558R polymorphism for atrial fibrillation in Tibetans living at different altitudes

Several studies have found associations of genes with atrial fibrillation (AF), including SCN5A-H558R. However, there are limited data of these associations among populations living at different altitudes. We investigated the relationship between the SCN5A-H558R polymorphism and AF in Tibetans living at different altitudes in Qinghai, China. General clinical and genotype data were obtained from 72 patients with AF and 109 non-AF (NAF) individuals at middle altitudes, and from 102 patients with AF and 143 NAF individuals at high altitudes. Multifactor logistic regression was performed to determine associations and AF risk factors. SCN5A-H558R genotypes differed significantly between the AF and NAF groups (P < .0125) and the G allele was an independent AF risk factor (P < .05) at both altitudes, with no significant differences according to altitude (P > .0125). At middle altitudes, age, red blood cell distribution width (RDW-SD), left atrial internal diameter (LAD), and G allele were independent AF risk factors. At high altitudes, age, smoking, hypertension, RDW-SD, free triiodothyronine, LAD, and G allele were independent AF risk factors (P < .05). The G allele of SCN5A-H558R might be an independent risk factor of AF both high and middle altitude, but there are some differences in other clinical risk factors of AF.

Research Progress on Natural Products’ Therapeutic Effects on Atrial Fibrillation by Regulating Ion Channels

Antiarrhythmic drugs (AADs) have a therapeutic effect on atrial fibrillation (AF) by regulating the function of ion channels. However, several adverse effects and high recurrence rates after drug withdrawal seriously affect patients’ medication compliance and clinical prognosis. Thus, safer and more effective drugs are urgently needed. Active components extracted from natural products are potential choices for AF therapy. Natural products like Panax notoginseng (Burk.) F.H. Chen, Sophora flavescens Ait., Stephania tetrandra S. Moore., Pueraria lobata (Willd.) Ohwi var. thomsonii (Benth.) Vaniot der Maesen., and Coptis chinensis Franch. have a long history in the treatment of arrhythmia, myocardial infarction, stroke, and heart failure in China. Based on the classification of chemical structures, this article discussed the natural product components’ therapeutic effects on atrial fibrillation by regulating ion channels, connexins, and expression of related genes, in order to provide a reference for development of therapeutic drugs for atrial fibrillation.

Screening and functional analysis of differentially expressed lncRNAs in rapid atrial pacing dog atrial tissue

PURPOSE

Atrial fibrillation (AF) is one of the most commonly sustained arrhythmias in clinical practice. Long non-coding RNAs (lncRNAs) are gene regulatory elements involved in the development of several diseases. We aimed to explore the expression characteristics of lncRNAs associated with AF.

METHODS

We randomly assigned 12 adult healthy mongrel dogs into a control group and an atrial pacing group. Atrial pacing stimulation was performed at a high frequency of 500 beats per min for 14 consecutive days in the atrial pacing group. HE and Masson staining were used to detect rapid atrial pacing induced atrial fibrosis. Total RNA extraction was performed on dog atrial tissues and was used for high-throughput sequencing of lncRNAs.

RESULTS

A total of 10,310 lncRNAs were detected, and 33 differentially expressed lncRNAs were screened. Among them, 19 lncRNAs were upregulated in the atrial pacing group, and 14 lncRNAs were downregulated. Gene Ontology (GO) classification, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and interaction networks showed that AF-related lncRNAs participate in the regulation of AF in diverse biological processes, cellular components, molecular functions, signaling pathways, and complex interactions with miRNAs and mRNAs. Five differentially expressed lncRNAs were selected for RT-PCR validation, and the verification results were consistent with the results of lncRNA sequencing.

CONCLUSIONS

In summary, our study enhances our understanding of the biological functions of AF-related lncRNAs by screening and analyzing differentially expressed lncRNAs, and the results help to enrich the theoretical basis for the treatment of atrial fibrillation.

The research of ion channel-related gene polymorphisms with atrial fibrillation in the Chinese Han population

BACKGROUND

Atrial fibrillation (AF) is one of the common arrhythmia in clinics. Its incidence is high among the elderly. This study aimed to identify a possible connection between ion channel-related gene polymorphisms and the risk of AF.

METHODS

A total of 381 patients with coronary heart disease were recruited. Based on complete cardiac examination, the patients were divided into two subgroups: 185 patients with AF and 196 patients without AF. An association analysis was performed using 13 genotyped SNPs. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by conditional logistic regression.

RESULTS

In our research, we found that KCNE2 rs8134775 was associated with a decreased AF risk in the allele model (OR = 0.70; 95% CI: 0.50-0.97; p = 0.034). Genetic model analysis shown that the minor allele T of GJA5 rs35594137 was associated with a decreased AF risk under the recessive model (OR = 0.40; 95% CI: 0.19-0.86; p = 0.018) and the minor allele G of KCNJ2 rs8079702 was associated with an increased AF risk in the recessive model (OR = 2.31; 95% CI: 1.20-4.42; p = 0.012).

CONCLUSIONS

Our results suggest that KCNE2, KCNJ2, and GJA5 influence the development of AF.