microRNA-133a attenuates cardiomyocyte hypertrophy by targeting PKCδ and Gq

Electrochemiluminescence Cascade Amplification Platform for Detection of Dual-microRNA and Operation of Concatenated Logic Circuit

The detection of multiple biomarkers is of great significance to the accurate diagnosis of diseases. Herein, in this work, we constructed an electrochemiluminescence (ECL) cascade amplification platform for dual acute myocardial infarction (AMI)-related microRNA detection. The Zn²⁺-dependent DNAzyme digestion reaction initiated by miR-133a and the duplex-specific nuclease (DSN) cleavage circuit initiated by miR-499 were carried out independently to form a fuel hairpin DNA and active initiator strand, respectively, to trigger a hybridization chain reaction, which constituted a two-input-regulated "AND" logic circuit based on single ECL signal output. The use of single signal probe (Ru(bpy)₃²⁺) avoided the time-consuming and costly process of multiple signal molecule labeling or modification. The independent operation of the DNAzyme digestion reaction and DSN-assisted target recycling improved the detection efficiency of the system. In addition, the detection of each miRNA had undergone a cascade amplification process, which improved the detection sensitivity for each target. Furthermore, benefitting from the strong complexation of EDTA with Zn²⁺ and the flexible design of DNA sequences, the two-input "AND" logic gate was extended to a four-input "INHIBIT-AND-INHIBIT" concatenated logic circuit, which broadens the application of the ECL method in logic gates. We anticipate that this cascading amplification strategy can be widely applied in accurate diagnosis of AMI and the construction of ECL-based logic devices.

MicroRNA-30 regulates left ventricular hypertrophy in chronic kidney disease

Left ventricular hypertrophy (LVH) is a primary feature of cardiovascular complications in patients with chronic kidney disease (CKD). miRNA-30 is an important posttranscriptional regulator of LVH, but it is unknown whether miRNA-30 participates in the process of CKD-induced LVH. In the present study, we found that CKD not only resulted in LVH but also suppressed miRNA-30 expression in the myocardium. Rescue of cardiomyocyte-specific miRNA-30 attenuated LVH in CKD rats without altering CKD progression. Importantly, in vivo and in vitro knockdown of miRNA-30 in cardiomyocytes led to cardiomyocyte hypertrophy by upregulating the calcineurin signaling directly. Furthermore, CKD-related detrimental factors, such as fibroblast growth factor-23, uremic toxin, angiotensin II, and transforming growth factor–β, suppressed cardiac miRNA-30 expression, while miRNA-30 supplementation blunted cardiomyocyte hypertrophy induced by such factors. These results uncover a potentially novel mechanism of CKD-induced LVH and provide a potential therapeutic target for CKD patients with LVH.

Downregulation of myocardial miRNA-30 is involved in chronic kidney disease–induced left ventricular hypertrophy, whereas exogenous miRNA-30 rescue inhibits this process.

Influence of sodium ferulate on miR-133a and left ventricle remodeling in rats with myocardial infarction

To explore the influence of sodium ferulate (SF) on miR-133a and left ventricle remodeling (LVR) in rats with myocardial infarction (MI). The left coronary artery was ligated to create 36 ischemia-reperfusion (IR) rat models that were randomly divided into mock surgical group (MSG) (not ligated), model group (MG), and sodium ferulate group (SFG). After the successful modeling, SFG was intravenously injected with SF at the dose of 10 mg/kg, and the other two groups were injected with the same volume of normal saline. After 28 days, cardiac hemodynamic indices of all groups were measured; the myocardial infarction size (MIS), left ventricular mass index (LVMI), and collagen volume fraction (CVF) were calculated, the content of serum malondialdehyde (MDA) and activities of catalase (CAT), superoxide dismutase (SOD) and glutathione catalase (GSH-px) were detected by ELISA, and miR-133a expression in myocardial tissues of the left ventricle (LV) was detected by RT-qPCR. SF improved the cardiac hemodynamic indices of rat model and reduced the MIS, LVMI and CVF. SF decreased the serum MDA level and increased the serum CAT, SOD and GSH-px levels in rat model. SF increased the expression of miR-133a in myocardial tissue of rat model. Therefore, SF could effectively reduce the myocardial injury of IR rats and improve the LVR. Its mechanism may be related to the antioxygenation and upregulation of miR-133a.

Role of MicroRNAs in Diagnosis, Prognosis, and Treatment of Acute Heart Failure: Ambassadors from Intracellular Zone

Acute heart failure (AHF) is one of the burdensome diseases affecting a considerable proportion of the population. Recently, it has been demonstrated that micro-ribonucleic acids (miRNAs) can exert diagnostic, prognostic, and therapeutic roles in a variety of conditions including AHF. These molecules play essential roles in HF-related pathophysiology, particularly, cardiac fibrosis, and hypertrophy. Some miRNAs namely miRNA-423-5p are reported to have both diagnostic and prognostic capabilities. However, some studies suggest that combination of biomarkers is a much better way to achieve the highest accuracy such as the combination of miRNAs and N-terminal pro b-type Natriuretic Peptide (NT pro-BNP). Therefore, this review discusses different views towards various roles of miRNAs in AHF.

TAK733 attenuates adrenergic receptor-mediated cardiomyocyte hypertrophy via inhibiting ErkThr188 phosphorylation

BACKGROUND

Cardiac hypertrophy is an important risk factor for heart failure. The MEK-ERK axis has been reported as a major regulator in controlling cardiac hypertrophy. TAK733 is a potent and selective MEK inhibitor that suppresses cell growth in a broad range of cell lines.

OBJECTIVE

Therefore, we aimed to investigate the anti-hypertrophic effect of TAK733 in cardiomyocytes.

METHODS

Cardiomyocyte hypertrophy was induced with norepinephrine (NE) or phenylepinephrine (PE) using H9c2 cells. To confirm the cardiomyocyte hypertrophy, cell size and protein synthesis were measured and hypertrophy-related gene expression was estimated by reverse transcription polymerase chain reaction. To identify the signaling pathway involved, immunoblot analysis were performed.

RESULTS

We observed that NE activated MEK-ERK signaling and increased ANP and BNP expression, resulting in cardiomyocyte hypertrophy. TAK733 significantly reduced cardiomyocyte hypertrophy by regulating NE-induced ERK1/2 and ERKThr188 activation, hypertrophy marker expression, and cardiomyocyte hypertrophy through depression of MEK activity. In addition, we examined that PE-induced cardiomyocyte hypertrophy was also attenuated by TAK733.

CONCLUSIONS

Here, we report that TAK733 suppressed NE- or PE-induced cardiomyocyte hypertrophy by repressing a crucial component of cardiac hypertrophy-related pathways. These results suggest that TAK733 may be a useful therapeutics for cardiac hypertrophy and warrants further in vivo studies.

MicroRNAs in Cardiac Hypertrophy

Like other organs, the heart undergoes normal adaptive remodeling, such as cardiac hypertrophy, with age. This remodeling, however, is intensified under stress and pathological conditions. Cardiac remodeling could be beneficial for a short period of time, to maintain a normal cardiac output in times of need; however, chronic cardiac hypertrophy may lead to heart failure and death. MicroRNAs (miRNAs) are known to have a role in the regulation of cardiac hypertrophy. This paper reviews recent advances in the field of miRNAs and cardiac hypertrophy, highlighting the latest findings for targeted genes and involved signaling pathways. By targeting pro-hypertrophic genes and signaling pathways, some of these miRNAs alleviate cardiac hypertrophy, while others enhance it. Therefore, miRNAs represent very promising potential pharmacotherapeutic targets for the management and treatment of cardiac hypertrophy.

Neuronal NO synthase mediates plenylephrine induced cardiomyocyte hypertrophy through facilitation of NFAT-dependent transcriptional activity

Neuronal nitric oxide synthase (NOS1) has been consistently shown to be the predominant isoform of NOS and/or NOS-derived NO that may be involved in the myocardial remodeling including cardiac hypertrophy. However, the direct functional contribution of NOS1 in this process remains to be elucidated. Therefore, in the present study, we attempted to use silent RNA and adenovirus mediated silencing or overexpression to investigate the role of NOS1 and the associated molecular signaling mechanisms during OKphenylephrine (PE)-induced cardiac hypertrophy growth in neonatal rat ventricular cardiomyocytes (NRVMs). We found that the expression of NOS1 was enhanced in PE-induced hypertrophic cardiomyocytes. Moreover, LVNIO treatment, a selective NOS1 inhibitor, significantly decreased PE-induced NRVMs hypertrophy and [3H]-leucine incorporation. We demonstrated that NOS1 gene silencing attenuated both the increased size and the transcriptional activity of the hypertrophic marker atrial natriuretic factor (ANF) induced by PE stimulation. Further investigation suggested that deficiency of NOS1-induced diminished NRVMS hypertrophy resulted in decreased calcineurin protein expression and activity (assessed by measuring the transcriptional activity of NFAT) and, an increased activity of the anti-hypertrophic pathway, GSK-3β (estimated by its augmented phosphorylated level). In contrast, exposing the NOS1 overexpressed NRVMs to PE-treatment further increased the hypertrophic growth, ANF transcriptional activity and calcineurin activity. Together, the results of the present study suggest that NOS1 is directly involved in controlling the development of cardiomyocyte hypertrophy.

Role of miRNAs on the Pathophysiology of Cardiovascular Diseases

MiRNA (or microRNA) is a subclass of non-coding RNAs that is responsible for post-transcriptional gene regulation. It has approximately 22 nucleotides and regulates gene expression in plants and animals at the post-transcriptional level, by the cleavage of a target mRNA or by suppression of its translation. Although many of the processes and mechanisms have not yet been fully elucidated, there is a strong association between miRNA expression and several diseases. It is known that miRNAs are expressed in the cardiovascular system, but their role in cardiovascular diseases (CVDs) has not been clearly established. In this non-systematic review of the literature, we first present the definition of miRNAs and their action at the cellular level. Afterward, we discuss the role of miRNAs as circulating biomarkers of CVDs, and then their role in cardiac remodeling and atherosclerosis. Despite the complexity and challenges, it is crucial to identify deregulated miRNAs in CVDs, as it allows a better understanding of underlying cellular and molecular mechanisms and helps in the development of more accurate diagnostic and prognostic circulating biomarkers, and new therapeutic strategies for different stages of CVDs.

lncRNA UCA1 Is a Novel Regulator in Cardiomyocyte Hypertrophy through Targeting the miR-184/HOXA9 Axis

Cardiac hypertrophy is closely associated with a series of cardiovascular diseases, including heart failure and sudden death in particular. An in-depth comprehension of the pathogenesis of cardiac hypertrophy will improve the diagnosis and therapy of cardiac hypertrophy. It has been acknowledged that long noncoding RNAs/microRNAs (lncRNAs/miRNAs) are crucial regulators in diverse biological processes, including various cardiovascular diseases, in multiple manners. Nevertheless, the biological roles of lncRNA UCA1 and miR-184 in cardiac hypertrophy are scarcely reported. In this paper, qRT-PCR analysis exhibited that lncRNA UCA1 was highly expressed in mice heart treated with transverse aortic constriction (TAC) and the cardiomyocytes treated with phenylephrine (PE). On the contrary, miR-184 was downregulated under the same conditions. In addition, it was deduced that lncRNA UCA1 was reversely related with miR-184 in PE-triggered hypertrophic cardiomyocytes, confirmed by the Spearman correlation analysis. The knockdown of UCA1 or the overexpression of miR-184 lessened the enlarged surface area of cardiomyocytes and the elevated expressions of fetal genes (ANP and BNP) induced by PE. Later, it was determined that miR-184 was a direct target of UCA1, whereas the mRNA HOXA9 was a target of miR-184. Rescue assays indicated that UCA1 promoted the progression of cardiac hypertrophy through competitively binding with miR-184 to enhance the expression of HOXA9.