MiR-208b/miR-21 Promotes the Progression of Cardiac Fibrosis Through the Activation of the TGF-β1/Smad-3 Signaling Pathway: An in vitro and in vivo Study

Dual-Encoded Affinity Microbead Signature Combinatorial Profiling for Acute Myocardial Infarction High-Sensitivity Diagnosis

The early diagnosis of acute myocardial infarction (AMI) is dependent on the combined feedback of multiple cardiac biomarkers. However, it remains challenging to precisely detect multicardiac biomarkers in complex blood early due to the lack of sensitive and specific diagnostic indicators and the low abundance and small size of associated biomarkers with high specificity (such as microRNAs). To make matters worse, spectral overlap significantly limits the multiplex analysis of cardiac biomarkers by fluorescent probes, leading to bias in the diagnosis of myocardial infarction. Herein, we developed a method for simultaneous detection of miRNAs and protein biomarkers using size- and color-coded microbeads that carry signature for target capture. We also constructed a microfluidic chip with different spacer arrays that segregate these microbeads in different chip regions according to their size to produce signature signals, indicating the level of different biomarkers. The signals on the microbeads were hugely amplified by catalytic hairpin assembly and rolling circle amplification. Notably, this strategy enables the simultaneous and in situ sensitive profiling of six kinds of biomarkers via adding two different fluorescent labels, removing the limitations of spectral overlap. We envision that the strategy has great potential for application in clinical diagnosis for AMI.

Inhibitory effect of microRNA-21 on pathways and mechanisms involved in cardiac fibrosis development

Cardiac fibrosis is a pivotal cardiovascular disease (CVD) process and represents a notable health concern worldwide. While the complex mechanisms underlying CVD have been widely investigated, recent research has highlighted microRNA-21's (miR-21) role in cardiac fibrosis pathogenesis. In this narrative review, we explore the molecular interactions, focusing on the role of miR-21 in contributing to cardiac fibrosis. Various signaling pathways, such as the RAAS, TGF-β, IL-6, IL-1, ERK, PI3K-Akt, and PTEN pathways, besides dysregulation in fibroblast activity, matrix metalloproteinases (MMPs), and tissue inhibitors of MMPs cause cardiac fibrosis. Besides, miR-21 in growth factor secretion, apoptosis, and endothelial-to-mesenchymal transition play crucial roles. miR-21 capacity regulatory function presents promising insights for cardiac fibrosis. Moreover, this review discusses numerous approaches to control miR-21 expression, including antisense oligonucleotides, anti-miR-21 compounds, and Notch signaling modulation, all novel methods of cardiac fibrosis inhibition. In summary, this narrative review aims to assess the molecular mechanisms of cardiac fibrosis and its essential miR-21 function.

An emerging view on vascular fibrosis molecular mediators and relevant disorders: from bench to bed

Vascular fibrosis is a widespread pathologic condition that arises during vascular remodeling in cardiovascular dysfunctions. According to previous studies, vascular fibrosis is characterized by endothelial matrix deposition and vascular wall thickening. The RAAS and TGF-β/Smad signaling pathways have been frequently highlighted. It is, however, far from explicit in terms of understanding the cause and progression of vascular fibrosis. In this review, we collected and categorized a large number of molecules which influence the fibrosing process, in order to acquire a better understanding of vascular fibrosis, particularly of pathologic dysfunction. Furthermore, several mediators that prevent vascular fibrosis are discussed in depth in this review, with the aim that this will contribute to the future prevention and treatment of related conditions.

Transpulmonary Expression of Exosomal microRNAs in Idiopathic and Congenital Heart Disease-Related Pulmonary Arterial Hypertension

BACKGROUND

Pulmonary artery hypertension (PAH) is a fatal disease characterized by a complex pathogenesis. Exosomes containing microRNAs (miRs) have emerged as a novel biomarker. Transpulmonary exosomal miRs offer valuable insights into pulmonary circulation microenvironments. Hereby, we aimed to explore the potentials of transpulmonary exosomal miRs as differentiating factors between idiopathic PAH and congenital heart disease (CHD)-related PAH.

METHODS AND RESULTS

During right heart catheterization, we collected exosomes at pulmonary arteries in 25 patients diagnosed with idiopathic PAH and 20 patients with CHD-related PAH. Next-generation sequencing identified several candidate exosomal miRs. Using quantitative polymerase chain reaction, we validated the expressions of these miRs and revealed significantly elevated expressions of miR-21, miR-139-5p, miR-155-5p, let-7f-5p, miR-328-3p, miR-330-3p, and miR-103a-3p in patients with CHD-related PAH, in contrast to patients with idiopathic PAH. Among these miRs, miR-21 exhibited the highest expression in patients with CHD-related PAH. These findings were further corroborated in an external cohort comprising 10 patients with idiopathic PAH and 8 patients with CHD-related PAH. Using an in vitro flow model simulating the shear stress experienced by pulmonary endothelial cells, we observed a significant upregulation of miR-21. Suppressing miR-21 rescued the shear stress-induced downregulation of the RAS/phosphatidylinositol 3-kinase/protein kinase B pathway, leading to a mitigation of apoptosis.

CONCLUSIONS

Our study identified a pronounced expression of transpulmonary exosomal miR-21, particularly in patients with CHD-related PAH, through next-generation sequencing analysis. Further investigation is warranted to elucidate the regulatory mechanisms involving miR-21 in the pathophysiology of PAH.

[Clinical importance of evaluation of circulating miRNA expression and epicardial adipose tissue thickness as predictors of cardiovascular pathology in young patients with type 1 diabetes mellitus]

Cardiovascular disease (CVD) in type 1 diabetes mellitus (T1DM) is preceded by asymptomatic changes in the geometry of the heart. The only symptoms of the beginning of cardiac remodeling and concomitant predictors of an unfavorable cardiovascular prognosis are: thickening of epicardial fat (EAT), secreting a number of adipokines, and cardiospecific miRNAs. To improve the effectiveness of prevention of CVD in young patients with DM1, a search was made for structural-functional and epigenetic markers.

AIM

To assess the state of the cardiovascular system according to MRI-heart with T1 mapping in T1DM without CVD. To reveal the relationship of epigenetic markers (circulating miR-126-5p, miR-21-5p) and adipokines with cardiovascular system in T1DM. Suggested personalized approach to patients with T1DM with initial manifestations of joint remodeling and/or exclusion of cardiospecific microRNA.

MATERIALS AND METHODS

The study included 40 patients: 30 with T1DM (age 26.2±7.4 years), 10 without T1DM (26.4±8.2). The patients underwent a general clinical examination, bioimpedancemetry, electrocardiography, MRI of the heart with T1 mapping, determination of adiponectin, resistin, visfatin, NT-proBNP, miR-126-5p, miR-21-5p.

RESULTS

Patients with T1DM had lower levels of cardioprotective miR-126-5p (p=0.046). According to MRI of the heart in T1DM, signs of vascular remodeling were revealed - thickening of the interventricular septum (p=0.001), posterior wall (p=0.012) and relative size of the walls (p=0.048) of the left ventricle, an increase in EAT density (p=0.001). Diffuse vascular fibrosis was found in 16% of patients from the T1DM group. Also, in T1DM, the expression of visfatin is increased (p=0.036) and adiponectin is reduced (p=0.043).

CONCLUSION

Structural and functional changes in the cardiovascular system (including thickening of the EAT), shifts in miR-126-5p expression and adipokines profile are observed already at a young age in patients with T1DM. In T1DM, diffuse vascular fibrosis is detected in 16% of patients. The data obtained were used to identify the group increased risk of developing CVD in T1DM and served as the basis for determining the timing of the start of preventive therapy.

PFKFB3 Inhibitor 3PO Reduces Cardiac Remodeling after Myocardial Infarction by Regulating the TGF-β1/SMAD2/3 Pathway

Adverse cardiac remodeling, including cardiac fibrosis, after myocardial infarction (MI) is a major cause of long-term heart failure. 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), an enzyme that regulates glucose metabolism, also plays an important role in various fibrotic and cardiovascular diseases. However, its effects on MI remain unknown. Here, PFKFB3 inhibitor 3-(3-pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3PO) and a permanent left anterior descending ligation mouse model were used to explore the functional role of PFKFB3 in MI. We showed that PFKFB3 expression increased significantly in the area of cardiac infarction during the early phase after MI, peaking on day 3. 3PO treatment markedly improved cardiac function, accompanied by decreased infarction size and collagen density in the infarct area. Meanwhile, 3PO attenuated cardiac fibrosis after MI by reducing the expression of collagen and fibronectin in murine hearts. Notably, 3PO reduced PFKFB3 expression and inhibited the transforming growth factor-beta 1/mothers against the decapentaplegic homolog 2/3 (TGF-β1/SMAD2/3) signaling pathway to inhibit cardiac fibrosis after MI. Moreover, PFKFB3 expression in neonatal rat cardiac fibroblasts (NRCFs) increased significantly after MI and under hypoxia, whereas 3PO alleviated the migratory capacity and activation of NRCFs induced by TGF-β1. In conclusion, 3PO effectively reduced fibrosis and improved adverse cardiac remodeling after MI, suggesting PFKFB3 inhibition as a novel therapeutic strategy to reduce the incidence of chronic heart failure following MI.

miRNA Dysregulation in Cardiovascular Diseases: Current Opinion and Future Perspectives

MicroRNAs (miRNAs), small noncoding RNAs, are post-transcriptional gene regulators that can promote the degradation or decay of coding mRNAs, regulating protein synthesis. Many experimental studies have contributed to clarifying the functions of several miRNAs involved in regulatory processes at the cardiac level, playing a pivotal role in cardiovascular disease (CVD). This review aims to provide an up-to-date overview, with a focus on the past 5 years, of experimental studies on human samples to present a clear background of the latest advances to summarize the current knowledge and future perspectives. SCOPUS and Web of Science were searched using the following keywords: (miRNA or microRNA) AND (cardiovascular diseases); AND (myocardial infarction); AND (heart damage); AND (heart failure), including studies published from 1 January 2018 to 31 December 2022. After an accurate evaluation, 59 articles were included in the present systematic review. While it is clear that miRNAs are powerful gene regulators, all the underlying mechanisms remain unclear. The need for up-to-date data always justifies the enormous amount of scientific work to increasingly highlight their pathways. Given the importance of CVDs, miRNAs could be important both as diagnostic and therapeutic (theranostic) tools. In this context, the discovery of “TheranoMIRNAs” could be decisive in the near future. The definition of well-setout studies is necessary to provide further evidence in this challenging field.

Mechanism of action of non-coding RNAs and traditional Chinese medicine in myocardial fibrosis: Focus on the TGF-β/Smad signaling pathway

Cardiac fibrosis is a serious public health problem worldwide that is closely linked to progression of many cardiovascular diseases (CVDs) and adversely affects both the disease process and clinical prognosis. Numerous studies have shown that the TGF-β/Smad signaling pathway plays a key role in the progression of cardiac fibrosis. Therefore, targeted inhibition of the TGF-β/Smad signaling pathway may be a therapeutic measure for cardiac fibrosis. Currently, as the investigation on non-coding RNAs (ncRNAs) move forward, a variety of ncRNAs targeting TGF-β and its downstream Smad proteins have attracted high attention. Besides, Traditional Chinese Medicine (TCM) has been widely used in treating the cardiac fibrosis. As more and more molecular mechanisms of natural products, herbal formulas, and proprietary Chinese medicines are revealed, TCM has been proven to act on cardiac fibrosis by modulating multiple targets and signaling pathways, especially the TGF-β/Smad. Therefore, this work summarizes the roles of TGF-β/Smad classical and non-classical signaling pathways in the cardiac fibrosis, and discusses the recent research advances in ncRNAs targeting the TGF-β/Smad signaling pathway and TCM against cardiac fibrosis. It is hoped, in this way, to give new insights into the prevention and treatment of cardiac fibrosis.