A combined linkage, microarray and exome analysis suggests MAP3K11 as a candidate gene for left ventricular hypertrophy

Single-cell and genome-wide Mendelian randomization identifies causative genes for gout

BACKGROUND

Gout is a prevalent manifestation of metabolic osteoarthritis induced by elevated blood uric acid levels. The purpose of this study was to investigate the mechanisms of gene expression regulation in gout disease and elucidate its pathogenesis.

METHODS

The study integrated gout genome-wide association study (GWAS) data, single-cell transcriptomics (scRNA-seq), expression quantitative trait loci (eQTL), and methylation quantitative trait loci (mQTL) data for analysis, and utilized two-sample Mendelian randomization study to comprehend the causal relationship between proteins and gout.

RESULTS

We identified 17 association signals for gout at unique genetic loci, including four genes related by protein-protein interaction network (PPI) analysis: TRIM46, THBS3, MTX1, and KRTCAP2. Additionally, we discerned 22 methylation sites in relation to gout. The study also found that genes such as TRIM46, MAP3K11, KRTCAP2, and TM7SF2 could potentially elevate the risk of gout. Through a Mendelian randomization (MR) analysis, we identified three proteins causally associated with gout: ADH1B, BMP1, and HIST1H3A.

CONCLUSION

According to our findings, gout is linked with the expression and function of particular genes and proteins. These genes and proteins have the potential to function as novel diagnostic and therapeutic targets for gout. These discoveries shed new light on the pathological mechanisms of gout and clear the way for future research on this condition.

Circular RNA ACTA1 Acts as a Sponge for miR-199a-5p and miR-433 to Regulate Bovine Myoblast Development through the MAP3K11/MAP2K7/JNK Pathway

Circular RNAs (circRNAs) are a special class of noncoding RNA molecules that regulate many different biological processes. Myogenesis, a complex process, is primarily regulated by myogenic regulatory factors (MRFs) and various noncoding RNAs. However, the functions and regulatory mechanisms of circRNAs in myoblast development are unclear. In this study, we analyzed circRNA sequencing data of bovine myocyte tissues and identified circACTA1. Functional assays showed that circACTA1 could inhibit bovine myocyte proliferation and promote cell apoptosis and cytodifferentiation. In addition, circACTA1 could promote muscle repair in vivo. Mechanistically, luciferase assay and RNA immunoprecipitation were used to examine the interaction between circACTA1, miR-199a-5p, miR-433, and the target genes MAP3K11 and MAPK8. Meanwhile, we found that miR-199a-5p and miR-433 could suppress the expression of MAP3K11 and MAPK8, respectively. However, circACTA1 could mitigate this effect and activate the JNK signaling pathway. In conclusion, our results suggest that circACTA1 regulates the multiplication, apoptosis, and cytodifferentiation of bovine myocytes by competitively combining with miR-199a-5p and miR-433 to activate the mitogen-activated protein kinase kinase kinase 11 (MAP3K11)/mitogen-activated protein kinase kinase 7 (MAP2K7)/JNK signaling pathway.

Correlations of circulating miR-26b level with left ventricular hypertrophy and cardiac function in elderly patients with hypertension

Objectives:

To study the correlations of circulating miR-26b level with left ventricular hypertrophy (LVH) and cardiac function in elderly patients with hypertension.

Methods:

A total of 132 eligible patients were divided into low and high miR-26b level groups. Their baseline clinical data and biochemical indices were compared. The correlations between miR-26b level and echocardiographic parameters were studied by Pearson’s analysis. Factors affecting LVH were explored by multivariate logistic regression analysis. The role of miR-26b in diagnosing LVH was predicted by receiver operating characteristic curve.

Results:

The relative expression level of miR-26b was 4.56-16.93, with a median of 7.62. The two groups had similar baseline clinical data and biochemical indices (P>0.05). Compared with high miR-26b level group, interventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), left ventricular mass index (LVMI) and number of LVH cases in low miR-26b level group significantly increased (P<0.05), and mitral ratio of peak early to late diastolic filling velocity (E/A) decreased (P<0.05). Circulating miR-26b level was negatively correlated with IVST, LVPWT and LVMI (P<0.0001), and positively correlated with E/A (P<0.0001). The proportion of cardiac hypofunction cases in low miR-26b level group significantly exceeded that of high miR-26b level group (P<0.05). Age and increased IVST, LVPWT and LVMI were independent risk factors for LVH (P<0.05), and elevated miR-26b level was a protective factor (P<0.05). AUC was 0.836, and the optimal cutoff value was 8.83, with high sensitivity and specificity.

Conclusions:

MiR-26b level is negatively correlated with LVH and positively correlated with left ventricular diastolic function in elderly hypertensive patients. It is a protective factor for LVH complicated with diastolic dysfunction and a potential biomarker for diagnosis.

miR-140-5p aggravates hypoxia-induced cell injury via regulating MLK3 in H9c2 cells

Myocardial infarction (MI) is an important cause of cardiovascular disease. microRNAs (miRNAs) have been indicated as pivotal regulators in the physiological and pathological processes of heart diseases. The purpose of this study was to investigate the role of miR-140-5p in hypoxia-induced cell injury in H9c2 cells and its underlying mechanism. H9c2 cells were subjected to hypoxia, before which the expression levels of miR-140-5p and MLK3 were overexpressed or knocked down through transient transfection. The efficiency of transfection was verified by qRT-PCR and Western blotting. Cell viability, apoptotic cell rate, and the expression changes of apoptosis-related proteins were determined by trypan blue exclusion, flow cytometry, and Western blotting, respectively. Furthermore, Western blotting was performed to assess the expression levels of core factors related with p38MAPK and JNK signaling pathways. As a result, hypoxia significantly reduced cell viability and increased cell apoptosis in H9c2 cells. miR-140-5p inhibition attenuated cell injury induced by hypoxia in H9c2 cells, while miR-140-5p overexpression expedited the cell injury, as evidenced by the decreased cell viability and enhanced cell apoptosis. Moreover, miR-140-5p promoted the activation of p38MAPK and JNK pathways. miR-140-5p positively modulated the expression of MLK3. ML3 overexpression reversed the regulatory effects of miR-140-5p inhibition on hypoxia-injured H9c2 cells. In conclusion, this study demonstrated that miR-140-5p aggravated hypoxia-induced cell injury partially through up-regulation of MLK3.