MiRNA-1/133a Clusters Regulate Adrenergic Control of Cardiac Repolarization

The electrical properties of the heart are primarily determined by the activity of ion channels and the activity of these molecules is permanently modulated and adjusted to the physiological needs by adrenergic signaling. miRNAs are known to control the expression of many proteins and to fulfill distinct functions in the mammalian heart, though the in vivo effects of miRNAs on the electrical activity of the heart are poorly characterized. The miRNAs miR-1 and miR-133a are the most abundant miRNAs of the heart and are expressed from two miR-1/133a genomic clusters. Genetic modulation of miR-1/133a cluster expression without concomitant severe disturbance of general cardiomyocyte physiology revealed that these miRNA clusters govern cardiac muscle repolarization. Reduction of miR-1/133a dosage induced a longQT phenotype in mice especially at low heart rates. Longer action potentials in cardiomyocytes are caused by modulation of the impact of β-adrenergic signaling on the activity of the depolarizing L-type calcium channel. Pharmacological intervention to attenuate β-adrenergic signaling or L-type calcium channel activity in vivo abrogated the longQT phenotype that is caused by modulation of miR-1/133a activity. Thus, we identify the miR-1/133a miRNA clusters to be important to prevent a longQT-phenotype in the mammalian heart.     

Metabolic Maturation during Muscle Stem Cell Differentiation Is Achieved by miR-1/133a-Mediated Inhibition of the Dlk1-Dio3 Mega Gene Cluster

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Changes in Acetyl CoA Levels during the Early Embryonic Development of Xenopus laevis

Coenzyme A (CoA) is a ubiquitous and fundamental intracellular cofactor. CoA acts as a carrier of metabolically important carboxylic acids in the form of CoA thioesters and is an obligatory component of a multitude of catabolic and anabolic reactions. Acetyl CoA is a CoA thioester derived from catabolism of all major carbon fuels. This metabolite is at a metabolic crossroads, either being further metabolised as an energy source or used as a building block for biosynthesis of lipids and cholesterol. In addition, acetyl CoA serves as the acetyl donor in protein acetylation reactions, linking metabolism to protein post-translational modifications. Recent studies in yeast and cultured mammalian cells have suggested that the intracellular level of acetyl CoA may play a role in the regulation of cell growth, proliferation and apoptosis, by affecting protein acetylation reactions. Yet, how the levels of this metabolite change in vivo during the development of a vertebrate is not known. We measured levels of acetyl CoA, free CoA and total short chain CoA esters during the early embryonic development of Xenopus laevis using HPLC. Acetyl CoA and total short chain CoA esters start to increase around midblastula transition (MBT) and continue to increase through stages of gastrulation, neurulation and early organogenesis. Pre-MBT embryos contain more free CoA relative to acetyl CoA but there is a shift in the ratio of acetyl CoA to CoA after MBT, suggesting a metabolic transition that results in net accumulation of acetyl CoA. At the whole-embryo level, there is an apparent correlation between the levels of acetyl CoA and levels of acetylation of a number of proteins including histones H3 and H2B. This suggests the level of acetyl CoA may be a factor, which determines the degree of acetylation of these proteins, hence may play a role in the regulation of embryogenesis.     

Involvement of NEAT1/miR-133a axis in promoting cervical cancer progression via targeting SOX4

NEAT1 is an important tumor oncogenic gene in various tumors. Nevertheless, its involvement remains poorly studied in cervical cancer. Our study explored the functional mechanism of NEAT1 in cervical cancer. NEAT1 level in several cervical cancer cells was quantified and we found NEAT1 was greatly upregulated in vitro. NEAT1 knockdown inhibited cervical cancer development through repressing cell proliferation, colony formation, capacity of migration, and invasion and also inducing the apoptosis. For another, microRNA (miR)-133a was downregulated in cervical cancer cells and NEAT1 negatively modulated miR-133a expression. Subsequently, we validated that miR-133a functioned as a potential target of NEAT1. Meanwhile, SOX4 is abnormally expressed in various cancers. SOX4 was able to act as a downstream target of miR-133a and silencing of SOX4 can restrain cervical cancer progression. In addition, in vivo assays were conducted to prove the role of NEAT1/miR-133a/SOX4 axis in cervical cancer. These findings implied that NEAT1 served as a competing endogenous RNA to sponge miR-133a and regulate SOX4 in cervical cancer pathogenesis. To sum up, it was implied that NEAT1/miR-133a/SOX4 axis was involved in cervical cancer development.     

Expression and regulation of miR-1, -133a, -206a, and MRFs by thyroid hormone during larval development in Paralichthys olivaceus

MiR-1, miR-133a, and miR-206a have been identified as muscle-specific miRNAs. They play multiple crucial roles in the regulation of muscle development. Here, we show that these miRNAs were differentially expressed during the larval development of flounder, and specifically expressed in skeletal muscle and heart in adult tissues/organs. The expression levels of these miRNAs were significantly changed by thyroid hormone (TH) or thiourea (TU) treatment during metamorphosis from 17 dph (days post hatching) to 42 dph. In addition, the expression levels of MyoD and Myf5 mRNAs markedly increased at 14 dph (pre-metamorphosis) compared to metamorphic stages, and their expression levels are far above the myogenin during larval development. Moreover, these MRFs (myogenic regulatory factors) expression were directly or indirectly regulated by thyroid hormone or thiourea during metamorphosis. All the results suggest that miRNAs and MRFs might be involved in signaling pathway of TH or TU-mediated flounder metamorphosis.     

外周血miR-223和血清BNP水平在慢性心力衰竭患者中的诊断价值

目的:探究慢性心力衰竭(chronic heart failure,CHF)患者外周血microRNA-223(miR-223)和血清B型利钠肽(B-type natriuretic peptide,BNP)水平及其诊断价值。方法:选取CHF患者65例(CHF组),其中美国纽约心脏病协会(New York Heart Association,NYHA)心功能分级Ⅱ级24例,Ⅲ级22例,Ⅳ级19例。另取40例同期在体检中心进行健康体检者(Control组),采用实时荧光定量PCR检测外周血中miR-223水平,ELISA检测血清BNP含量,ROC曲线评价miR-223及BNP对CHF的诊断价值。结果:CHF组左心室短轴缩短率及左心室射血分数显著低于Control组(P0.01);左心室舒张末期内径显著高于Control组(P0.01)。CHF组不同NYHA心功能分级患者miR-223和BNP水平均高于Control组,且miR-223和BNP水平随NYHA心功能分级逐渐递增,组间两两比较均显示统计学差异(P0.05)。miR-223诊断CHF的曲线下面积(area under the curve,AUC)为0.7375,临界值为43.51时灵敏度为92.82%,特异度为89.44%;BNP诊断CHF的AUC为0.7925,临界值为128 ng/L时灵敏度为92.93%,特异度为92.58%。结论:CHF患者外周血miR-223和血清BNP水平高于健康对照人群,其对CHF的诊断具有一定的临床参考价值。     

特应性皮炎患儿外周血miR-122a和miR-146a水平与Th1/Th2/Th17免疫平衡的相关性分析

摘要 目的：探讨特应性皮炎（AD）患儿外周血微小核糖核酸（miRNA）-122a和miR-146a水平与辅助性T细胞（Th）1/Th2/Th17免疫平衡的相关性。方法：选取2020年5月～2023年5月石家庄市妇幼保健院皮肤科收治的AD患儿100例为AD组,根据特应性皮炎评分（SCORAD）分为轻度组31例、中度组41例、重度组28例,另选取同期100名体检健康儿童为对照组。采用实时荧光定量聚合酶链式反应检测外周血miR-122a、miR-146a水平,流式细胞术检测外周血Th1、Th2、Th17细胞比例,酶联免疫吸附法检测外周血Th1、Th2、Th17相关细胞因子[白细胞介素（IL）-2、干扰素-γ（IFN-γ）、IL-4、IL-13、IL-17、IL-22]水平,并计算Th1/Th2/Th17比值。采用Pearson/Spearman相关性分析AD患儿外周血miR-122a、miR-146a与Th1、Th2、Th17和相关细胞因子及Th1/Th2/Th17的相关性。结果：AD组外周血miR-122a、miR-146a、Th1、Th1/Th2/Th17、IL-2、IFN-γ水平低于对照组,Th2、Th17、IL-4、IL-13、IL-17、IL-22水平高于对照组（P均＜0.05）。轻度组、中度组、重度组外周血miR-122a、miR-146a、Th1、Th1/Th2/Th17、IL-2、IFN-γ水平依次降低,Th2、Th17、IL-4、IL-13、IL-17、IL-22水平依次升高（P均＜0.05）。Pearson/Spearman相关性分析显示,AD患儿外周血miR-122a、miR-146a与Th1、Th1/Th2/Th17、IL-2、IFN-γ水平呈正相关（r/rs分别为0.679、0.677、0.684、0.706、0.693、0.689、0.671、0.694,P均＜0.001）,与Th2、Th17、IL-4、IL-13、IL-17、IL-22呈负相关（r/rs分别为-0.690、-0.680、-0.681、-0.669、-0.675、-0.676、-0.676、-0.686、-0.682、-0.674、-0.680、-0.689,P均＜0.001）。结论：AD患儿外周血miR-122a、miR-146a水平降低,与病情严重程度密切相关,可能通过调节Th1/Th2/Th17免疫平衡参与AD发生发展。     

MALAT1 regulates hypertrophy of cardiomyocytes by modulating the miR-181a/HMGB2 pathway

Noncoding RNAs are important for the regulation of cardiac hypertrophy. The function of MALAT1 (a long noncoding mRNA), miR-181a, and HMGB2, their contribution to cardiac hypertrophy, and the regulatory relationship between them during this process remain unknown. In the present study, we treated primary cardiomyocytes with angiotensin II (Ang II) to mimic cardiac hypertrophy. MALAT1 expression was significantly downregulated in Ang II-treated cardiomyocytes compared with control cardiomyocytes. Ang II-induced cardiac hypertrophy was suppressed by overexpression of MALAT1 and promoted by genetic knockdown of MALAT1. A dual-luciferase reporter assay demonstrated that MALAT1 acted as a sponge for miR-181a and inhibited its expression during cardiac hypertrophy. Cardiac hypertrophy was suppressed by overexpression of an miR-181a inhibitor and enhanced by overexpression of an miR-181a mimic. HMGB2 was downregulated during cardiac hypertrophy and was identified as a target of miR-181a by bioinformatics analysis and a dual-luciferase reporter assay. miR-181a overexpression decreased the mRNA and protein levels of HMGB2. Rescue experiments indicated that MALAT1 overexpression reversed the effect of miR-181a on HMGB2 expression. In summary, the results of the present study show that MALAT1 acts as a sponge for miR-181a and thereby regulates expression of HMGB2 and development of cardiac hypertrophy. The novel MALAT1/miR-181a/HMGB2 axis might play a crucial role in cardiac hypertrophy and serve as a new therapeutic target.Key words: Hypertrophy, cardiomyocytes, MALAT1, miR-181a, HMGB2     

慢性心力衰竭患者外周血miR-148a表达水平与炎症因子、心功能和心室重构的关系

摘要 目的：探讨慢性心力衰竭（CHF）患者血清miR-148a表达水平与炎症因子、心功能和心室重构的关系。方法：选择2017年1月~2019年1月在我院就诊的CHF患者136例,按照美国纽约心脏病学会（NYHA）心功能分级将患者分为Ⅱ级57例、Ⅲ级43例和Ⅳ级36例。实时荧光定量PCR检测血清miR-148a的表达,血清中白细胞介素-1（IL-1）、白细胞介素6（IL-6）和肿瘤坏死因子-α（TNF-α）的含量用酶联免疫吸附试验检测,使用超声心动图检测心功能和心室重构指标,主要包括左室舒张末期内径（LVEDD）、舒张末室间隔厚度（IVSD）、舒张末左室后壁厚度（PWD）、左室质量指数（LVMI）、左室射血分数（LVEF）和左室重构指数（LVRI）,采用Pearson积矩相关系数分析血清miR-148a表达水平与血清炎症因子、超声心动图指标之间的相关性。结果：CHF患者血清miR-148a表达量随心功能分级升高而降低（P均<0.05）。炎症因子（IL-1、IL-6和TNF-α）水平和LVEDD、PWD、IVSD、LVMI随心功能分级升高而升高, LVRI和LVEF随心功能分级升高而降低（P<0.05）。血清miR-148a表达量与炎症因子、IVSD、PWD和LVMI呈负相关（P<0.05）;与LVEF和LVRI呈正相关（P<0.05）。结论：血清miR-148a表达量与CHF患者血清炎症因子水平、心功能及心室重构关系密切,提示检测血清miR-148a有助于反映CHF患者病情的严重程度。