The Emerging Role of MicroRNA-155 in Cardiovascular Diseases

MicroRNA-210 Enhances Cell Survival and Paracrine Potential for Cardiac Cell Therapy While Targeting Mitophagy

The therapeutic potential of presumed cardiac progenitor cells (CPCs) in heart regeneration has garnered significant interest, yet clinical trials have revealed limited efficacy due to challenges in cell survival, retention, and expansion. Priming CPCs to survive the hostile hypoxic environment may be key to enhancing their regenerative capacity. We demonstrate that microRNA-210 (miR-210), known for its role in hypoxic adaptation, significantly improves CPC survival by inhibiting apoptosis through the downregulation of Casp8ap2, a ~40% reduction in caspase activity, and a ~90% decrease in DNA fragmentation. Contrary to the expected induction of Bnip3-dependent mitophagy by hypoxia, miR-210 did not upregulate Bnip3, indicating a distinct anti-apoptotic mechanism. Instead, miR-210 reduced markers of mitophagy and increased mitochondrial biogenesis and oxidative metabolism, suggesting a role in metabolic reprogramming. Furthermore, miR-210 enhanced the secretion of paracrine growth factors from CPCs, with a ~1.6-fold increase in the release of stem cell factor and of insulin growth factor 1, which promoted in vitro endothelial cell proliferation and cardiomyocyte survival. These findings elucidate the multifaceted role of miR-210 in CPC biology and its potential to enhance cell-based therapies for myocardial repair by promoting cell survival, metabolic adaptation, and paracrine signalling.

Targeting miRNA with flavonoids: unlocking novel pathways in cardiovascular disease management

Cardiovascular disease (CVD) remains the leading cause of mortality worldwide, with complex pathophysiological mechanisms such as oxidative stress, inflammation, apoptosis, and endothelial dysfunction driving disease progression. MicroRNAs (miRNAs), a class of non-coding RNAs, have emerged as key regulators of gene expression involved in these processes, positioning them as potential biomarkers and therapeutic targets in CVD management. Simultaneously, flavonoids, naturally occurring polyphenolic compounds found in various plant-based foods, have gained attention for their cardioprotective properties, including antioxidant, anti-inflammatory, and anti-apoptotic effects. Recent studies suggest a novel intersection between flavonoids and miRNAs, where flavonoids may modulate the expression of specific miRNAs implicated in CVD pathogenesis. This review explores the potential of flavonoids as miRNA modulators, focusing on their ability to regulate miRNAs associated with cardiac fibrosis, hypertrophy, and vascular inflammation. By bridging the therapeutic potential of flavonoids with miRNA targeting, this review highlights innovative pathways for advancing CVD treatment strategies. Additionally, preclinical and clinical evidence supporting these interactions is discussed, alongside the challenges and opportunities in developing flavonoid-based miRNA therapies. Unlocking this synergy could pave the way for more effective, personalized approaches to CVD management, addressing unmet needs in contemporary cardiovascular care.

Diagnostic and Prognostic Role of Circulating microRNAs in Patients with Coronary Artery Disease-Impact on Left Ventricle and Arterial Function

Recent studies reported that circulating microRNAs (miRNAs) can target different metalloproteases (MMPs) involved in matrix remodeling and plaque vulnerability. Consequently, they might have a role in the diagnosis and prognosis of coronary artery disease. To quantify circulating miRNAs (miRNA126, miRNA146, and miRNA21) suggested to have possible cardiovascular implications, as well as levels of MMP-1 and MMP-9, and to determine their association with left ventricular (LV) function and with arterial function, in patients with either ST-segment elevation acute myocardial infarction (STEMI) or stable ischemic heart disease (SIHD). A total of 90 patients with coronary artery disease (61% men, 58 ± 12 years), including 60 patients with STEMI and 30 patients with SIHD, were assessed within 24 h of admission, by measuring serum microRNAs, and serum MMP-1 and MMP-9. LV function was assessed by measuring ejection fraction (EF) by 2D and 3D echocardiography, and global longitudinal strain (GLS) by speckle tracking. Arterial function was assessed by echo tracking, CAVI, and peripheral Doppler. Circulating levels of miRNA146, miRNA21, and MMP1 were significantly increased in patients with STEMI vs. SIHD (p = 0.0001, p = 0.0001, p = 0.04, respectively). MiRNA126 negatively correlated with LVEF (r = -0.33, p = 0.01) and LV deformation parameters (r = -0.31, p = 0.03) in patients with STEMI and negatively correlated with ABI parameters (r = -0.39, p = 0.03, r = -0.40, p = 0.03, respectively) in patients with SIHD. MiRNA146 did not have any significant correlations, while higher values of miRNA21 were associated with lower values of GLS in STEMI patients and with higher values of GLS in SIHD patients. Both MMP1 and MMP9 correlated negatively with LVEF (r = -0.27, p = 0.04, r = -0.40, p = 0.001, respectively) and GLS in patients with STEMI, and positively with arterial stiffness in patients with SIHD (r = 0.40 and r = 0.32, respectively; both p < 0.05). MiRNA126, miRNA21, and both MMP1 and MMP9 are associated with LV and arterial function parameters in patients with acute coronary syndrome. Meanwhile, they inversely correlate with arterial function in patients with chronic atherosclerotic disease. However, further studies are needed to establish whether these novel biomarkers have diagnosis and prognosis significance.

Cardiovascular Risk in Philadelphia-Negative Myeloproliferative Neoplasms: Mechanisms and Implications-A Narrative Review

Myeloproliferative neoplasms (MPNs), encompassing disorders like polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are characterized by clonal hematopoiesis without the Philadelphia chromosome. The JAK2 V617F mutation is prevalent in PV, ET, and PMF, while mutations in MPL and CALR also play significant roles. These conditions predispose patients to thrombotic events, with PMF exhibiting the lowest survival among MPNs. Chronic inflammation, driven by cytokine release from aberrant leukocytes and platelets, amplifies cardiovascular risk through various mechanisms, including atherosclerosis and vascular remodeling. Additionally, MPN-related complications like pulmonary hypertension and cardiac fibrosis contribute to cardiovascular morbidity and mortality. This review consolidates recent research on MPNs' cardiovascular implications, emphasizing thrombotic risk, chronic inflammation, and vascular stiffness. Understanding these associations is crucial for developing targeted therapies and improving outcomes in MPN patients.

Evaluation of MicroRNA 145 and MicroRNA 155 as Markers of Cardiovascular Risk in Chronic Kidney Disease

Background Chronic kidney disease (CKD) leads to a progressive decline in renal function, primarily due to deteriorating kidney structures. Vascular calcification is a key effect of CKD. MicroRNAs (miRNAs) play a significant role in the onset and progression of both cardiovascular illness and CKD. Aim The aim of this study was to compare biomarkers of endothelial dysfunction, 25-hydroxyvitamin D (25(OH)D), intact parathyroid hormone (iPTH), miRNA 155, and miRNA 145, in patients with CKD versus controls. Methods We recruited 60 patients with CKD and 60 controls. All participants underwent brachial artery flow-mediated dilatation (FMD). Asymmetric dimethylarginine (ADMA) levels were measured using ELISA. Levels of miRNA 145 and miRNA 155 were quantified using real-time polymerase chain reaction (PCR). Results Serum levels of miRNA 145, miRNA 155, 25(OH)D, and FMD were significantly lower in CKD patients compared to controls. Conversely, serum ADMA and iPTH levels were significantly higher in CKD patients. There was a significant negative association between miRNA 145, miRNA 155, FMD, and 25(OH)D with ADMA and iPTH. Additionally, miRNA 145, miRNA 155, FMD, and 25(OH)D showed a significant positive correlation with estimated glomerular filtration rate (eGFR) and with each other. Conclusion Lower levels of miRNA 145 and miRNA 155 and increased endothelial dysfunction correlate with CKD severity, suggesting an accelerated risk for cardiovascular disease (CVD).

The Interplay Between Cytokines and MicroRNAs to Regulate Metabolic Disorders

Metabolic disorders represent significant public health challenges worldwide. Emerging evidence suggests that cytokines and microRNAs (miRNAs) play crucial roles in the pathogenesis of metabolic disorders by regulating various metabolic processes, including insulin sensitivity, lipid metabolism, and inflammation. This review provides a comprehensive overview of the intricate interplay between cytokines and miRNAs in the context of metabolic disorders, including obesity, type 2 diabetes, and cardiovascular diseases. We discuss how dysregulation of cytokine-miRNA networks contributes to the development and progression of metabolic disorders and explore the therapeutic potential of targeting these interactions for disease management.

The Role of Circulating MicroRNAs in Cardiovascular Diseases: A Novel Biomarker for Diagnosis and Potential Therapeutic Targets?

MicroRNAs, involved in a large variety of pathological conditions, tend to be potential specific biomarkers in cardiovascular diseases. Moreover, these short, non-coding RNAs, regulate post-transcriptional gene expression and protein synthesis, making them ideal for therapeutic targets. Down-regulation and up-regulation of specific microRNAs are currently studied as a novel approach to the diagnosis and treatment of cardiovascular diseases, such as chronic and acute coronary syndromes, atherosclerosis, heart failure, and arrhythmia. MicroRNAs are interesting and attractive targets for cardiovascular-associated therapeutics because of their stability, tissue-specific expression pattern, and secretion of body fluids. Extended research on their isolation, detection, and function will provide the standardization needed for using microRNAs as biomarkers and potential therapeutic targets. This review will summarize recent data on the implication of microRNAs in cardiovascular diseases, their potential role as biomarkers for diagnosis, and also the challenges of using microRNAs as future therapeutic targets.

Predicting miRNA-Disease Associations by Combining Graph and Hypergraph Convolutional Network

miRNAs are important regulators for many crucial biological processes. Many recent studies have shown that miRNAs are closely related to various human diseases and can be potential biomarkers or therapeutic targets for some diseases, such as cancers. Therefore, accurately predicting miRNA-disease associations is of great importance for understanding and curing diseases. However, how to efficiently utilize the characteristics of miRNAs and diseases and the information on known miRNA-disease associations for prediction is still not fully explored. In this study, we propose a novel computational method for predicting miRNA-disease associations. The proposed method combines the graph convolutional network and the hypergraph convolutional network. The graph convolutional network is utilized to extract the information from miRNA-similarity data as well as disease-similarity data. Based on the representations of miRNAs and diseases learned by the graph convolutional network, we further use the hypergraph convolutional network to capture the complex high-order interactions in the known miRNA-disease associations. We conduct comprehensive experiments with different datasets and predictive tasks. The results show that the proposed method consistently outperforms several other state-of-the-art methods. We also discuss the influence of hyper-parameters and model structures on the performance of our method. Some case studies also demonstrate that the predictive results of the method can be verified by independent experiments.

MicroRNAs in chronic pediatric diseases (Review)

MicroRNAs are small non-coding RNAs with a length of 20-24 nucleotides. They bind to the 3'-untranslated region of target genes to induce the degradation of target mRNAs or inhibit their translation. Therefore, they are involved in the regulation of development, apoptosis, proliferation, differentiation and other biological processes (including hormone secretion, signaling and viral infections). Chronic diseases in children may be difficult to treat and are often associated with malnutrition resulting from a poor diet. Consequently, further complications, disease aggravation and increased treatment costs impose a burden on patients and their families. Existing evidence suggests that microRNAs are involved in various chronic non-neoplastic diseases in children. The present review discusses the roles of microRNAs in five major chronic diseases in children, namely, diabetes mellitus, congenital heart diseases, liver diseases, bronchial asthma and epilepsy, providing a theoretical basis for them to become therapeutic biomarkers in chronic pediatric diseases.

Beyond acute infection: molecular mechanisms underpinning cardiovascular complications in long COVID

SARS-CoV-2, responsible for the global COVID-19 pandemic, has manifested significant cardiovascular implications for the infected population. These cardiovascular repercussions not only linger beyond the initial phase of illness but have also been observed in individuals who remain asymptomatic. This extended and pervasive impact is often called the post-acute COVID-19 syndrome (PACS) or "Long COVID". With the number of confirmed global cases approaching an alarming 756 million, the multifaceted challenges of Long COVID are undeniable. These challenges span from individual health complications to considerable burdens on worldwide healthcare systems. Our review comprehensively examines the complications of the persistent cardiovascular complications associated with COVID-19. Furthermore, we shed light on emerging therapeutic strategies that promise to manage and possibly mitigate these complications. We also introduce and discuss the profound concerns regarding the potential transgenerational repercussions of SARS-CoV-2, emphasizing the need for a proactive and informed approach to future research and clinical practice.

Network analysis identifies circulating miR-155 as predictive biomarker of type 2 diabetes mellitus development in obese patients: a pilot study

Obesity is the main risk factor for many non-communicable diseases. In clinical practice, unspecific markers are used for the determination of metabolic alterations and inflammation, without allowing the characterization of subjects at higher risk of complications. Circulating microRNAs represent an attractive approach for early screening to identify subjects affected by obesity more at risk of developing connected pathologies. The aim of this study was the identification of circulating free and extracellular vesicles (EVs)-embedded microRNAs able to identify obese patients at higher risk of type 2 diabetes (DM2). The expression data of circulating microRNAs derived from obese patients (OB), with DM2 (OBDM) and healthy donors were combined with clinical data, through network-based methodology implemented by weighted gene co-expression network analysis. The six circulating microRNAs overexpressed in OBDM patients were evaluated in a second group of patients, confirming the overexpression of miR-155-5p in OBDM patients. Interestingly, the combination of miR-155-5p with serum levels of IL-8, Leptin and RAGE was useful to identify OB patients most at risk of developing DM2. These results suggest that miR-155-5p is a potential circulating biomarker for DM2 and that the combination of this microRNA with other inflammatory markers in OB patients can predict the risk of developing DM2.

The Role of Epicardial Adipose Tissue-Derived MicroRNAs in the Regulation of Cardiovascular Disease: A Narrative Review

Cardiovascular diseases have been leading cause of death worldwide for many decades, and obesity has been acknowledged as a risk factor for cardiovascular diseases. In the present review, human epicardial adipose tissue-derived miRNAs reported to be differentially expressed under pathologic conditions are discussed and summarized. The results of the literature review indicate that some of the epicardial adipose tissue-derived miRNAs are believed to be cardioprotective, while some others show quite the opposite effects depending on the underlying pathologic conditions. Furthermore, they suggest that that the epicardial adipose tissue-derived miRNAs have great potential as both a diagnostic and therapeutic modality. Nevertheless, mainly due to highly limited availability of human samples, it is very difficult to make any generalized claims on a given miRNA in terms of its overall impact on the cardiovascular system. Therefore, further functional investigation of a given miRNA including, but not limited to, the study of its dose effect, off-target effects, and potential toxicity is required. We hope that this review can provide novel insights to transform our current knowledge on epicardial adipose tissue-derived miRNAs into clinically viable therapeutic strategies for preventing and treating cardiovascular diseases.

The Role of ncRNAs in Cardiac Infarction and Regeneration

Myocardial infarction is the most prevalent cardiovascular disease worldwide, and it is defined as cardiomyocyte cell death due to a lack of oxygen supply. Such a temporary absence of oxygen supply, or ischemia, leads to extensive cardiomyocyte cell death in the affected myocardium. Notably, reactive oxygen species are generated during the reperfusion process, driving a novel wave of cell death. Consequently, the inflammatory process starts, followed by fibrotic scar formation. Limiting inflammation and resolving the fibrotic scar are essential biological processes with respect to providing a favorable environment for cardiac regeneration that is only achieved in a limited number of species. Distinct inductive signals and transcriptional regulatory factors are key components that modulate cardiac injury and regeneration. Over the last decade, the impact of non-coding RNAs has begun to be addressed in many cellular and pathological processes including myocardial infarction and regeneration. Herein, we provide a state-of-the-art review of the current functional role of diverse non-coding RNAs, particularly microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in different biological processes involved in cardiac injury as well as in distinct experimental models of cardiac regeneration.

Fluoropyrimidine‑induced cardiotoxicity in colorectal cancer patients: a prospective observational trial (CHECKPOINT)

Fluoropyrimidines (FP) are the backbone chemotherapy in colorectal cancer (CRC) treatment; however, their use is associated with cardiotoxicity, which is underreported. In the present study, it was aimed to prospectively determine the incidence rates and related risk factors of FP‑induced cardiotoxicity (FIC) in CRC patients and at identifying predictive biomarkers. A total of 129 consecutive previously untreated CRC patients underwent active cardiological monitoring, including 5‑items simplified questionnaire on symptoms, electrocardiogram (ECG) and plasma sample collection during FP chemotherapy. FIC was defined as the presence of ECG alterations and/or the arising of at least one symptom of chest pain, dyspnoea, palpitations or syncope. The primary objective was the evaluation of FIC incidence. Secondary objectives were the correlation of FIC with well‑known cardiological risk factors and the identification of circulating biomarkers (serum levels of troponin I, pro hormone BNP; miRNA analysis) as predictors of FIC. A total of 20 out of 129 (15.5%) patients experienced FIC. The most common symptoms were dyspnoea (60%) and chest pain (40%), while only 15% of patients presented ECG alterations, including one acute myocardial infarction. Retreatment with FP was attempted in 90% of patients with a favourable outcome. Despite 48% of patients having cardiological comorbidities, an increased FIC was not observed in this subgroup. Only the subgroup of females with the habit of alcohol consumption showed an increased risk of FIC. None of the circulating biomarkers evaluated demonstrated a clinical utility as FIC predictors. FIC can be an unexpected, life‑threatening adverse event that can limit the subsequent treatment choices in patients with CRC. In this prospective study, well‑known cardiological comorbidities were not related to higher FIC risk and circulating biomarkers predictive of toxicity could not be found. With careful monitoring, mainly based on symptoms, almost all patients completed the FP treatment.

microRNAs Associated with Carotid Plaque Development and Vulnerability: The Clinician's Perspective

Ischemic stroke (IS) related to atherosclerosis of large arteries is one of the leading causes of mortality and disability in developed countries. Atherosclerotic internal carotid artery stenosis (ICAS) contributes to 20% of all cerebral ischemia cases. Nowadays, atherosclerosis prevention and treatment measures aim at controlling the atherosclerosis risk factors, or at the interventional (surgical or endovascular) management of mature occlusive lesions. There is a definite lack of the established circulating biomarkers which, once modulated, could prevent development of atherosclerosis, and consequently prevent the carotid-artery-related IS. Recent studies emphasize that microRNA (miRNA) are the emerging particles that could potentially play a pivotal role in this approach. There are some research studies on the association between the expression of small non-coding microRNAs with a carotid plaque development and vulnerability. However, the data remain inconsistent. In addition, all major studies on carotid atherosclerotic plaque were conducted on cell culture or animal models; very few were conducted on humans, whereas the accumulating evidence demonstrates that it cannot be automatically extrapolated to processes in humans. Therefore, this paper aims to review the current knowledge on how miRNA participate in the process of carotid plaque formation and rupture, as well as stroke occurrence. We discuss potential target miRNA that could be used as a prognostic or therapeutic tool.

TNFR2 is a regulatory target of pol-miR-194a and promotes the antibacterial immunity of Japanese flounder Paralichthys olivaceus

MicroRNAs (miRNAs) are regulatory RNAs that modulate target gene expression after transcription. Pol-miR-194a had been reported to be a miRNA of Japanese flounder (Paralichthys olivaceus) involved in Edwardsiella tarda infection. Here, we identified tumor necrosis factor receptor 2 (TNFR2) as a target gene of pol-miR-194a. Pol-miR-194a markedly repressed the protein expression of flounder TNFR2 (PoTNFR2) via specific interaction with the 3'UTR of PoTNFR2. PoTNFR2 responded to E. tarda infection in a manner that was opposite to that of pol-miR-194a and inhibited E. tarda invasion by activating the NF-κB pathway. Consistently, dysregulation of PoTNFR2 had a significant impact on E. tarda dissemination in flounder tissues. Together, these results add new insights into the regulation mechanism and immune function of fish TNFR2 and pol-miR-194a.

Peritoneal effluent MicroRNA profile for detection of encapsulating peritoneal sclerosis

BACKGROUND

Encapsulating peritoneal sclerosis (EPS) is a catastrophic complication of peritoneal dialysis (PD) with high mortality. Our aim is to develop a novel noninvasive microRNA (miRNA) test for EPS.

METHODS

We collected 142 PD effluents (EPS: 62 and non-EPS:80). MiRNA profiles of PD effluents were examined by a high-throughput real-time polymerase chain reaction (PCR) array to first screen. Candidate miRNAs were verified by single real-time PCR. The model for EPS prediction was evaluated by multiple logistic regression and machine learning.

RESULTS

Seven candidate miRNAs were identified from the screening of PCR-array of 377 miRNAs. The top five area under the curve (AUC) values with 5 miRNA-ratios were selected using 127 samples (EPS: 56 vs non-EPS: 71) to produce a receiver operating characteristic curve. After considering clinical characteristics and 5 miRNA-ratios, the accuracies of the machine learning model of Random Forest and multiple logistic regression were boosted to AUC 0.97 and 0.99, respectively. Furthermore, the pathway analysis of miRNA associated targeting genes and miRNA-compound interaction network revealed that these five miRNAs played the roles in TGF-β signaling pathway.

CONCLUSION

The model-based miRNA expressions in PD effluents may help determine the probability of EPS and provide further therapeutic opinion for EPS.

Regulating microglial miR-155 transcriptional phenotype alleviates Alzheimer's-induced retinal vasculopathy by limiting Clec7a/Galectin-3+ neurodegenerative microglia

Single cell RNA sequencing studies identified novel neurodegeneration-associated microglial (MGnD/DAM) subtypes activated around cerebral amyloid plaques. Micro-RNA (miR)-155 of the TREM2-APOE pathway was shown to be a key transcriptional regulator of MGnD microglial phenotype. Despite growing interest in studying manifestations of Alzheimer's disease (AD) in the retina, a CNS organ accessible to noninvasive high-resolution imaging, to date MGnD microglia have not been studied in the AD retina. Here, we discovered the presence and increased populations of Clec7a+ and Galectin-3+ MGnD microglia in retinas of transgenic APPSWE/PS1L166P AD-model mice. Conditionally targeting MGnD microglia by miR-155 ablation via the tamoxifen-inducible CreERT2 system in APPSWE/PS1L166P mice diminished retinal Clec7a+ and Galectin-3+ microglial populations while increasing homeostatic P2ry12+ microglia. Retinal MGnD microglia were often adhering to microvessels; their depletion protected the inner blood-retina barrier and reduced vascular amyloidosis. Microglial miR-155 depletion further limits retinal inflammation. Mass spectrometry analysis revealed enhanced retinal PI3K-Akt signaling and predicted IL-8 and Spp1 decreases in mice with microglia-specific miR-155 knockout. Overall, this study identified MGnD microglia in APPSWE/PS1L166P mouse retina. Transcriptional regulation of these dysfunctional microglia mitigated retinal inflammation and vasculopathy. The protective effects of microglial miR-155 ablation should shed light on potential treatments for retinal inflammation and vascular damage during AD and other ocular diseases.

MicroRNA-155 inhibition attenuates myocardial infarction-induced connexin 43 degradation in cardiomyocytes by reducing pro-inflammatory macrophage activation

BACKGROUND

Degradation of pro-inflammatory macrophage-mediated connexin 43 (Cx43) plays an important role in post-myocardial infarction (MI) arrhythmogenesis, microRNA (miR)-155 produced by macrophages has been shown to mediate post-MI effects. We hypothesized that miR-155 inhibition attenuated MI-induced Cx43 degradation by reducing pro-inflammatory macrophage activation.

METHODS

MI was induced by permanent ligation of the left anterior descending coronary artery in male C57BL/6 mice. Lipopolysaccharide (LPS)-stimulated mice bone marrow-derived macrophages (BMDMs) and hypoxia-induced neonatal rat cardiomyocytes (NRCMs) were used in vitro models. qRT-PCR, Western-blot and immunofluorescence were used to analyze relevant indicators.

RESULTS

The expression levels of miR-155, interleukin-1 beta (IL-1β), and matrix metalloproteinase (MMP)7 were higher in MI mice and LPS-treated BMDMs than in the sham/control groups, treatment with a miR-155 antagomir reversed these effects. Moreover, miR-155 inhibition reduced ventricular arrhythmias incidence and improved cardiac function in MI mice. Cx43 expression was decreased in MI mice and hypoxia-exposed NRCMs, and hypoxia-induced Cx43 degradation in NRCMs was reduced by application of conditioned medium from LPS-induced BMDMs treated with the miR-155 antagomir, but increased by conditioned medium from BMDMs treated with a miR-155 agomir. Importantly, NRCMs cultured in conditioned medium from LPS-induced BMDMs transfected with small interfering RNA against IL-1β and MMP7 showed decreased hypoxia-mediated Cx43 degradation, and this effect also was diminished by BMDM treatment with the miR-155 agomir. Additionally, siRNA-mediated suppressor of cytokine signaling 1 (SOCS1) knockdown in LPS-induced BMDMs promoted Cx43 degradation in hypoxia-exposed NRCMs, and the effect was reduced by the miR-155 inhibition.

CONCLUSIONS

MiR-155 inhibition attenuated post-MI Cx43 degradation by reducing macrophage-mediated IL-1β and MMP7 expression through the SOCS1/nuclear factor-κB pathway.

The exploration of quantum dot-molecular beacon based MoS2 fluorescence probing for myeloma-related Mirnas detection

Highly sensitive and reliable detection of multiple myeloma remains a major challenge in liquid biopsy. Herein, for the first time, quantum dot-molecular beacon (QD-MB) functionalized MoS₂ (QD-MB @MoS₂) fluorescent probes were designed for the dual detection of multiple myeloma (MM)-related miRNA-155 and miRNA-150. The results indicate that the two probes can effectively detect miRNA-155 and miRNA-150 simultaneously with satisfactory recovery rates, and the limit of detections (LODs) of miRNA-155 and miRNA-150 in human serum are low to 7.19 fM and 5.84 fM, respectively. These results indicate that our method is the most sensitive detection so far reported and that the designed fluorescent probes with signal amplification strategies can achieve highly sensitive detection of MM-related miRNAs for MM diagnosis.

•

Novel quantum dot-molecular beacon functionalized MoS₂ (QD-MB@MoS₂) fluorescent probes were designed and fabricated.

•

The dual detection of miRNA-155 and miRNA-150 with high sensitivity, low detection limit and high recovery was realized.

•

The fluorescence probes have a great influence on the fluorescence quenching efficiency and the sensitivity.

•

The new MB@MoS₂ fluorescent probe and dual detection strategy provide a valuable tool for the detection of miRNA.

MiR-21-5p-expressing bone marrow mesenchymal stem cells alleviate myocardial ischemia/reperfusion injury by regulating the circRNA_0031672/miR-21-5p/programmed cell death protein 4 pathway

BACKGROUND

For patients with coronary heart disease, reperfusion treatment strategies are often complicated by ischemia/reperfusion (I/R) injury (IRI), leading to serious organ damage and malfunction. The miR-21/programmed cell death protein 4 (PDCD4) pathway is involved in the IRI of cardiomyocytes; however, the aberrant miR-21 expression remains unexplained. Therefore, this study aimed to explore whether circRNA_0031672 downregulates miR-21-5p expression during I/R and to determine whether miR-21-5p-expressing bone marrow mesenchymal stem cells (BMSCs) reduce myocardial IRI.

METHODS

CircRNA_0031672, miR-21-5p, and PDCD4 expressions were evaluated in the I/R rat model and hypoxia/re-oxygenation (H/R)-treated H9C2 cells. Their interactions were subsequently investigated using luciferase reporter and RNA pulldown assays. Methyltransferase-like 3, a methyltransferase catalyzing N6-methyladenosine (m6A), was overexpressed in H9C2 cells to determine whether m6A modification influences miR-21-5p targeting PDCD4. BMSCs stably expressing miR-21 were co-cultured with H9C2 cells to investigate the protective effect of BMSCs on H9C2 cells upon H/R.

RESULTS

I/R downregulated miR-21-5p expression and upregulated circRNA_0031672 and PDCD4 expressions. CircRNA_0031672 knockdown increased miR-21-5p expression, but repressed PDCD4 expression, indicating that circRNA_0031672 competitively bound to miR-21-5p and prevented it from targeting PDCD4 mRNA. The m6A modification regulated PDCD4 expression, but had no effect on miR-21-5p targeting PDCD4. The circRNA_0031672/miR-21-5p/PDCD4 axis regulated myocardial cells viability and apoptosis after H/R treatment; co-culture with miR-21-5p-expressing BMSCs restored miR-21-5p abundance in H9C2 cells and further reduced H9C2 cells apoptosis induced by H/R.

CONCLUSIONS

We identified a novel circRNA_0031672/miR-21-5p/PDCD4 signaling pathway that mediates the apoptosis of cardiomyocytes and successfully alleviates IRI in myocardial cells by co-culture with miR-21-5p-expressing BMSCs, offering novel insights into the IRI pathogenesis in cardiovascular diseases.

miR-200a-3p improves neonatal necrotizing enterocolitis by regulating RIPK1

BACKGROUND

Necrotizing enterocolitis (NEC) is an acquired disease, which mainly occurs in premature infants or sick newborns. microRNA (miR), as a common non-coding RNA in recent years, is found in many diseases. In this research, miR usefulin NEC is analyzed by GEO.

METHOD

The differentially expressed miRs in NEC were screened by analyzing GSE68054, and miR-200a-3p in IEC-6 cells induced by lipopolysaccharide (LPS) and serum of NEC children were detected by qRT-PCR. The role of miR-200a-3p in LPS-induced IEC-6 cells was tested using CCK-8, PI dyeing, and inflammatory cytokine detection. The direct downstream molecules of miR-200a-3p were identified using TargetScanHuman and verified by luciferase reporter gene assay. The mechanism of action was explored using western blot.

RESULTS

miR-200a-3p in IEC-6 treated with NEC and LPS was significantly decreased. In vitro experiments revealed that miR-200a-3p mimetic could inhibit IL-6 and TNF-α in IEC-6 cells induced by LPS and reduce the positive rate of PI. In addition, it was determined that receptor-interacting protein kinase 1 (RIPK1) was a downstream molecule of miR-200a-3p, and overexpression of RIPK1 could aggravate LPS-induced IEC-6 injury, while miR-200a-3p mimics could alleviate the overexpression of RIPK1. miR-200a-3p mimics inhibited the elevation of necrosis-related molecules and the interaction between RIPK1 and RIPK3 in LPS-induced IEC-6 cells.

CONCLUSION

miR-200a-3p can protect intestinal epithelial cells from LPS injury by inhibiting inflammation and necrosis mediated by RIPK1, which provides a possible target for NEC.

Amnion membrane proteins attenuate LPS-induced inflammation and apoptosis by inhibiting TLR4/NF-κB pathway and repressing MicroRNA-155 in rat H9c2 cells

OBJECTIVE

Amnion membrane (AM) has been popular for the treatment of inflammatory disorders due to its cell repairing properties. This current study aims to find the underlying mechanisms of amnion membrane proteins (AMPs) against the pro-inflammatory miRNA, miR-155, miR-146, and anti-apoptotic microRNA, miR-21, in LPS-treated H9c2 cells.

METHODS

Cell viability and apoptosis were determined by MTT assay and annexin V/PI staining. The production of the cytokines, TNF-α and IL-6 were evaluated by using qPCR and Enzyme-linked immunosorbent assay (ELISA), respectively. In addition, the expression of miRNAs was quantified by qPCR, and also the protein level of TLR4 and NF-kβ was determined with western blotting.

RESULTS

We found that AMPs ameliorated LPS-induced reduction of cell viability and augment apoptosis in H9c2 cells. AMPs efficiently inhibited cytokine expression (IL-6 and TNF-α) and activity of TLR4/NF-κB pathway in LPS-treated H9c2 cells. Correspondingly, in parallel with the suppression of pro-inflammatory cytokines and apoptosis, AMPs mitigated pro-inflammatory miRNA, miR-155 expression, while, the expression of miR-155 was found to be increased in LPS-treated H9c2 cells. Also, AMPs activated miR-146 expression in H9c2 cells under LPS treatment. Additionally, the elevated expression of miR-21 provoked by LPS was further enhanced by AMPs.

CONCLUSIONS

In conclusion, AMPs could alleviate LPS-induced cardiomyocytes cells injury via up-regulation of miR-21, miR-146, and suppression of TLR4/NF-κB pathway, which plays a key role in the down-regulation of LPS-mediated miR-155 and inflammatory cytokine expression.

miR155 Deficiency Reduces Myofibroblast Density but Fails to Improve Cardiac Function after Myocardial Infarction in Dyslipidemic Mouse Model

Myocardial infarction remains the most common cause of heart failure with adverse remodeling. MicroRNA (miR)155 is upregulated following myocardial infarction and represents a relevant regulatory factor for cardiac remodeling by engagement in cardiac inflammation, fibrosis and cardiomyocyte hypertrophy. Here, we investigated the role of miR155 in cardiac remodeling and dysfunction following myocardial infarction in a dyslipidemic mouse model. Myocardial infarction was induced in dyslipidemic apolipoprotein E-deficient (ApoE^−/−) mice with and without additional miR155 knockout by ligation of the LAD. Four weeks later, echocardiography was performed to assess left ventricular (LV) dimensions and function, and mice were subsequently sacrificed for histological analysis. Echocardiography revealed no difference in LV ejection fractions, LV mass and LV volumes between ApoE^−/− and ApoE^−/−/miR155^−/− mice. Histology confirmed comparable infarction size and unaltered neoangiogenesis in the myocardial scar. Notably, myofibroblast density was significantly decreased in ApoE^−/−/miR155^−/− mice compared to the control, but no difference was observed for total collagen deposition. Our findings reveal that genetic depletion of miR155 in a dyslipidemic mouse model of myocardial infarction does not reduce infarction size and consecutive heart failure but does decrease myofibroblast density in the post-ischemic scar.

The pathological growth of the prostate gland in atherogenic contexts

The human prostate is an androgen-dependent gland where an imbalance in cell proliferation can lead to benign prostatic hyperplasia (BPH), which results in voiding lower urinary tract symptoms in the elderly. In the last decades, novel evidence has suggested that BPH might represent an element into the wide spectrum of disorders conforming the Metabolic Syndrome (MS). The dyslipidemic state and the other atherogenic factors of the MS have been shown to induce, maintain and/or aggravate the pathological growth of different organs, with data regarding the prostate being still limited. We here review the available epidemiological and experimental studies about the association of BPH with dyslipidemias. In particular, we have focused on Oxidized Low-Density Lipoproteins (OxLDL) as a potential trigger for vascular disease and cellular proliferation in atherogenic contexts, analyzing their putative molecular mechanisms, including the induction of specific extracellular vesicles (EVs)-derived miRNAs. In addition to the epidemiological evidence, OxLDL is proposed to play a fundamental role in the upregulation of prostatic cell proliferation by activating the Rho/Akt/p27^Kip1 pathway in atherogenic contexts. miR-21, miR-141, miR-143, miR-145, miR-155, and miR-221 would be involved in the transcription of genes related to the proliferative process. Although much remains to be investigated regarding the impact of OxLDL, its receptors, and molecular mechanisms on the prostate, it is clear that EVs and miRNAs represent a promising target for proliferative pathologies of the prostate gland.

MiR-155 acts as an inhibitory factor in atherosclerosis-associated arterial pathogenesis by down-regulating NoxA1 related signaling pathway in ApoE-/- mouse

Background

To investigate the protective efficacy of miR-155 on down regulating NADPH oxidase isoform subunit A1 (NoxA1) gene expression, resulting in inhibition of VSMC migration and over proliferation and thus ameliorating the progression of arterial atherosclerosis in AS mouse model. Therefore, to further explore the regulatory effect of miR-155 on neointima formation in AS and locate potential anti-atherosclerosis target.

Methods

The mouse vascular aorta smooth muscle cell (MOVAS) was cultured and transfected with recombinant Pad2YFG adenovirus fluorescent vector with miR-155 fragment into 4 groups. Western blotting and RT-PCR were performed to identify the expression of NoxA1 under different circumstances. Fluorescence microscope was applied to observe the transfection rate of miR-155 into adenovirus. Twelve-week fatty food induced atherosclerotic ApoE^-/- mouse model was established as host to accept miR-155 transfected adenovirus transplantation to observe its effect on VSMC in AS progression. Carotid and thoracic artery were extracted at 1 month after dosing. Distribution of miR-155 was quantified via expression levels of protein and RNA to detect NoxA1, Nox1, p47phox and NADPH expression. Immunohistochemistry, fluorescence imaging and other methods were performed in arteries section to compare the thickness of neointima and assess the severity of AS in each group.

Results

Luciferase reporter gene assay showed significant expression of miR-155 in mimic group indicating that miR-155 had target binding effect with NoxA1 gene. Western blotting and RT-PCR results both showed significantly decreased NoxA1 expression in miR-155 mimic group while increased with its inhibitor. The miR-155 distribution was observed varied at 1 month after in control, miR-155 mimic and inhibitor groups. The NoxA1, NADPH, Nox1 and pp47phox protein expression in VSMC was decreased in mimic group vs control and inhibitor groups (P<0.05); no significant difference of NADPH expression was observed in all groups. The NoxA1, Nox1 and p47phox gene expression in VSMC were both found reduced compared with those of control group at week 4 (P<0.05). Immunohistochemistry staining of artery frozen sections figured out that the thickness of neointima of carotid artery in miR-155 mimic group was significantly lower vs control and inhibitor groups (P<0.01) at week 4.

Conclusions

miR-155 played an important role in NoxA1-related signaling pathway. miR-155 transfection into VSMC may have anti-inflammatory regulatory effect on NoxA1 expression in vivo and resulting in amelioration of atherosclerotic lesion in AS mouse model. In summary, miR-155 specifically plays in a negative feedback loop and demonstrates a protective role during atherosclerosis-associated VSMC proliferation and neointima formation through the miR-155-NoxA1-p47phox complex signaling pathway.

Inhibition of miR-155 Attenuates Detrimental Vascular Effects of Tobacco Cigarette Smoking

Background The role of microRNAs dysregulation in tobacco cigarette smoking-induced vascular damage still needs to be clarified. We assessed the acute effects of tobacco cigarette smoking on endothelial cell-related circulating microRNAs in healthy subjects. In addition, we investigated the potential role of microRNAs in smoking-dependent endothelial cell damage. Methods and Results A panel of endothelial-related microRNAs was quantified in healthy subjects before and after smoking 1 tobacco cigarette. Serum levels of miR-155 were found to be significantly increased shortly after smoking. We also observed a progressive and significant miR-155 accumulation in culture media of human endothelial cells after 30 minutes and up to 4 hours of cigarette smoke condensate treatment in vitro without evidence of cell death, indicating that miR-155 can be released by endothelial cells in response to smoking stress. Cigarette smoke condensate appeared to enhance oxidative stress and impair cell survival, angiogenesis, and NO metabolism in human endothelial cells. Notably, these effects were abrogated by miR-155 inhibition. We also observed that miR-155 inhibition rescued the deleterious effects of cigarette smoke condensate on endothelial-mediated vascular relaxation and oxidative stress in isolated mouse mesenteric arteries. Finally, we found that exogenous miR-155 overexpression mimics the effects of smoking stress by inducing the upregulation of inflammatory markers, impairing angiogenesis and reducing cell survival. These deleterious effects were associated with downregulation of vascular endothelial growth factor and endothelial NO synthetase. Conclusions Our results suggest that miR-155 dysregulation may contribute to the deleterious vascular effects of tobacco smoking.

MicroRNA profiling as a novel diagnostic tool for identification of patients with inflammatory and/or virally induced cardiomyopathies

AIMS

MicroRNAs (miRNAs) might be used as prospective biomarkers for the identification of unexplained heart failure caused by a viral and/or inflammatory process. The aim of this study was to identify and to evaluate prognostic miRNAs in serum of patients with inflammatory heart diseases diagnosed by endomyocardial biopsies.

METHODS AND RESULTS

After TaqMan® OpenArray® screening of 754 unique circulating miRNAs in serum of biopsy-proven patients [184 patients with inflammatory and/or virally induced myocardial diseases (DCMi), 25 patients with dilated cardiomyopathy (DCM), and 25 healthy donors], we identified seven miRNAs of interest (P < 0.05). These data have been verified by single qRT-PCR assays in other biopsy-proven patients (159 patients with viral and/or inflammatory myocardial diseases, 46 patients with DCM, and 60 healthy donors). The expression of let-7f, miR-197, miR-223, miR-93, and miR-379 allowed us to differentiate between patients with a virus and/or inflammation and healthy donors (P < 0.05) with the specificity over 93%. Based on the expression of miR-21 and miR-30a-5p, we could sort out patients with DCM from all other study groups (P < 0.05) with the specificity over 95%.

CONCLUSIONS

This miRNA profile provides for the first time a new non-invasive diagnostic perspective to identify patients with intramyocardial inflammation and/or viral persistence only from single serum sample, independently of prescribed therapy and time of symptoms onset. It allows the early finding of those patients relevant for myocardial biopsy for exact diagnosis and further proscription of causal aetiology-driven specific treatment.

Effects of ambient ozone exposure on circulating extracellular vehicle microRNA levels in coronary artery disease patients

Exposure to ambient air pollutants such as ozone (O₃) and particulate matter (PM) is associated with increased cardiovascular morbidity and rate of mortality, but the underlying biological mechanisms have yet to be described. Emerging evidence shows that extracellular vehicle (EV) microRNAs (miRNAs) may facilitate cell-to-cell and organ-to-organ communications and play a role in the air pollution-induced cardiovascular effects. This study aims to explore the association between air pollutant exposure and miRNA changes related to cardiovascular diseases. Using a panel study design, 14 participants with coronary artery diseases were enrolled in this study. Each participant had up to 10 clinical visits and their plasma samples were collected and measured for expression of miRNA-21 (miR-21), miR-126, miR-146, miR-150, and miR-155. Mixed effects models adjusted for temperature, humidity, and season were used to examine the association between miRNA levels and exposure to 8-hr O₃ or 24-hr PM_2.5 up to 4 days prior. Results demonstrated that miR-150 expression was positively associated with O₃ exposure at 1-4 days lag and 5day moving average while miR-155 expression tracked with O₃ exposure at lag 0. No significant association was found between miRNA expression and ambient PM_2.5 at any time point. β-blocker and diabetic medication usage significantly modified the correlation between O₃ exposure and miR-150 expression where the link was more prominent among non-users. In conclusion, evidence indicated an association between exposure to ambient O₃ and circulating levels of EV miR-150 and miR-155 was observed. These findings pointed to a future research direction involving miRNA-mediated mechanisms of O₃-induced cardiovascular effects.

Challenges in Using Circulating Micro-RNAs as Biomarkers for Cardiovascular Diseases

Micro-RNAs (miRNAs) play a pivotal role in the development and physiology of the cardiovascular system while they have been associated with multiple cardiovascular diseases (CVDs). Several cardiac miRNAs are detectable in circulation (circulating miRNAs; c-miRNAs) and are emerging as diagnostic and therapeutic biomarkers for CVDs. c-miRNAs exhibit numerous essential characteristics of biomarkers while they are extremely stable in circulation, their expression is tissue-/disease-specific, and they can be easily detected using sequence-specific amplification methods. These features of c-miRNAs are helpful in the development of non-invasive assays to monitor the progress of CVDs. Despite significant progress in the detection of c-miRNAs in serum and plasma, there are many contradictory publications on the alterations of cardiac c-miRNAs concentration in circulation. The aim of this review is to examine the pre-analytical and analytical factors affecting the quantification of c-miRNAs and provide general guidelines to increase the accuracy of the diagnostic tests in order to improve future research on cardiac c-miRNAs.

Circulating plasma microRNA-126, microRNA-145, and microRNA-155 and their association with atherosclerotic plaque characteristics

AIMS

Circulating microRNAs (miRNAs) have been identified as biomarkers for several diseases. Dysregulation of miRNA-126, microRNA-145, and microRNA-155 has been shown to be associated with atherosclerotic lesion formation. The aim of this study was to evaluate the association between atherosclerosis-related miRNAs and unfavorable atherosclerotic plaque characteristics.

METHODS AND RESULTS

Forty patients with stable coronary artery disease admitted for elective percutaneous coronary intervention (PCI) were enrolled in a prospective study. After PCI, intravascular ultrasound (IVUS), and iMAP-IVUS analysis were performed to assess the proportion of fibrotic, necrotic, lipidic, and calcific tissue within atherosclerotic plaques. Total RNA was isolated from plasma to evaluate the expression of circulating miRNA-126, miRNA-145, and miRNA-155. Plasma lipid and glucose metabolism-related variables were measured to determine any association with plaque characteristics or miRNA expression. Expression of miRNA-126 was negatively correlated with plaque fibrotic tissue (r=-0.28; P=0.044), while positively correlated with plaque necrotic tissue (r=0.31; P=0.029) and necrolipidic tissue (r=0.31; P=0.031). MiRNA-145 was positively correlated with plaque lipidic (r=0.32; P=0.023) and necrolipidic tissue (r=0.31; P=0.029). Patient age was associated with plaque fibrotic tissue (r=-0.41; P=0.005), necrotic tissue (r=0.33; P=0.022), and lipid content (r=0.33; P=0.022). High-density lipoprotein cholesterol was positively correlated with plaque necrotic (r=0.28; P=0.042) and calcific (r=0.28; P=0.044) tissue volume. Calcific tissue volume was positively correlated with C-peptide (r=0.34; P=0.033). After multivariate logistic regression analysis, both miRNA-126 and miRNA-145 expressions were associated with increased necrolipidic tissue content (β=0.34; P=0.050; and β=0.35; P=0.037, respectively).

CONCLUSIONS

Expressions of miRNA-126 and miRNA-145 were associated with increased plaque necrolipidic tissue content.

RELEVANCE FOR PATIENTS

Although further research is needed to support the study data, miRNA-126 and miRNA-145 may serve as potential plaque vulnerability biomarkers in the future.

The Role of microRNAs in the Development of Type 2 Diabetes Complications

MicroRNAs represent a class of small (19-25 nucleotides) single-strand pieces of RNA that are noncoding ones. They are synthesized by RNA polymerase II from transcripts that fold back on themselves. They mostly act as gene regulatory agents that pair with complementary sequences on mRNA and produce silencing complexes, which, in turn, suppress coding genes at a post-transcriptional level. There is now evidence that microRNAs may affect insulin secretion or insulin action, as they can alter pancreatic beta cells development, insulin production, as well as insulin signaling. Any molecular disorder that affects these pathways can deteriorate insulin resistance and lead to type 2 diabetes mellitus (T2DM) onset. Furthermore, the expression of several microRNAs is up- or down-regulated in the presence of diabetic microvascular complications (i.e., peripheral neuropathy, nephropathy, retinopathy, foot ulcers), as well as in patients with coronary heart disease, stroke, and peripheral artery disease. However, more evidence is needed, specifically regarding T2DM patients, to establish the use of such microRNAs as diagnostical biomarkers or therapeutic targets in daily practice.

Redox-sensitive, PEG-shielded carboxymethyl PEI nanogels silencing MicroRNA-21, sensitizes resistant ovarian cancer cells to cisplatin

A series of branched polyethylenimine (PEI) modifications including PEGylation (PEG2k-PEI) for steric shielding, redox-sensitive crosslinking for synthesis PEG2k-PEI-ss nanogels and subsequent carboxymethylation (PEG2k-CMPEI-ss) for modulation of the polymer pka have been introduced for cellular delivery of Anti-miR-21. The synthesis was characterized using 1H NMR, FTIR, TNBS, potentiometric titration, particle size and ζ potential. Loading of Anti-miR-21 at various N/P ratios was investigated by gel retardation, ethidium bromide dye exclusion, heparin sulfate competition and DNase I digestion experiments. The miR-21 silencing was measured by stem-loop RT PCR in A2780 ovarian cancer cell lines whether it is sensitive to resistant to cisplatin. It has been shown that PEG2k-CMPEI-ss was well suited for delivery of Anti-miR-21 in terms of nucleic acid loading, preservation against extracellular matrix and nucleases and sequence-specific silencing of miRNA-21 in vitro. Moreover, it has been demonstrated that pre-treating cells with Anti-miR-21 loaded nanogels can sensitize them to cis-Pt even at non-toxic concentraions. The results indicate that PEG2k-CMPEI-ss mediated microRNA delivery can be considered as a novel strategy for ovarian cancer therapy.

An improved random forest-based computational model for predicting novel miRNA-disease associations

Background

A large body of evidence shows that miRNA regulates the expression of its target genes at post-transcriptional level and the dysregulation of miRNA is related to many complex human diseases. Accurately discovering disease-related miRNAs is conductive to the exploring of the pathogenesis and treatment of diseases. However, because of the limitation of time-consuming and expensive experimental methods, predicting miRNA-disease associations by computational models has become a more economical and effective mean.

Results

Inspired by the work of predecessors, we proposed an improved computational model based on random forest (RF) for identifying miRNA-disease associations (IRFMDA). First, the integrated similarity of diseases and the integrated similarity of miRNAs were calculated by combining the semantic similarity and Gaussian interaction profile kernel (GIPK) similarity of diseases, the functional similarity and GIPK similarity of miRNAs, respectively. Then, the integrated similarity of diseases and the integrated similarity of miRNAs were combined to represent each miRNA-disease relationship pair. Next, the miRNA-disease relationship pairs contained in the HMDD (v2.0) database were considered positive samples, and the randomly constructed miRNA-disease relationship pairs not included in HMDD (v2.0) were considered negative samples. Next, the feature selection based on the variable importance score of RF was performed to choose more useful features to represent samples to optimize the model’s ability of inferring miRNA-disease associations. Finally, a RF regression model was trained on reduced sample space to score the unknown miRNA-disease associations. The AUCs of IRFMDA under local leave-one-out cross-validation (LOOCV), global LOOCV and 5-fold cross-validation achieved 0.8728, 0.9398 and 0.9363, which were better than several excellent models for predicting miRNA-disease associations. Moreover, case studies on oesophageal cancer, lymphoma and lung cancer showed that 94 (oesophageal cancer), 98 (lymphoma) and 100 (lung cancer) of the top 100 disease-associated miRNAs predicted by IRFMDA were supported by the experimental data in the dbDEMC (v2.0) database.

Conclusions

Cross-validation and case studies demonstrated that IRFMDA is an excellent miRNA-disease association prediction model, and can provide guidance and help for experimental studies on the regulatory mechanism of miRNAs in complex human diseases in the future.

Cardioprotective Effect of Danhong Injection against Myocardial Infarction in Rats Is Critically Contributed by MicroRNAs

Background

Danhong injection (DHI) has been mainly used for the treatment of myocardial infarction, atherosclerosis, and coronary heart disease in clinical practice. Our previous studies have shown that DHI improves ventricular remodeling and preserves cardiac function in rats with myocardial infarction (MI). In this study, we focused on the potential mechanism of DHI in protecting cardiac function in MI rats.

Methods

Sprague-Dawley rats were subjected to ligation of the left anterior descending coronary artery (LAD) to prepare a myocardial infarction (MI) model. After 14 day DHI intervention, cardiac function was measured by echocardiography and myocardial fibrosis was assessed by Masson staining. Differentiated miRNAs were screened using rat immunopathology miScript miRNA PCR arrays, and their results were verified by RT-PCR, immunofluorescence, and immunoblotting.

Results

DHI treatment significantly reduced infarct size and improved cardiac function and hemodynamics in MI rats by echocardiography and morphology. miRNA PCR array results showed that DHI reversed 25 miRNAs known to be associated with inflammation and apoptosis. Moreover, the expression of inflammatory factors TNF-α, IL-1β, and IL-6 was significantly reduced in the treated DHI group. Mechanistically, DHI downregulated the inflammatory transcription factor NF-κB (as reflected by inhibition of NF-κB p65 nuclear translocation and phosphorylation of the IκBα).

Conclusions

DHI is effective in mitigating inflammation associated with MI by preventing NF-κB nuclear translocation and regulating miRNAs, thereby improving cardiac function in myocardial infarction rats.

MiR-26a-5p enhances cells proliferation, invasion, and apoptosis resistance of fibroblast-like synoviocytes in rheumatoid arthritis by regulating PTEN/PI3K/AKT pathway

Behavior alterations in fibroblast-like synoviocytes (FLS) contribute to a pivotal role in pathogenesis of rheumatoid arthritis (RA). MiRNAs are closely involved in a variety of pathologic conditions. In the present study, we aimed to screen for the aberrant expression of miRNAs in rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) to further identify the altered expression of miR-26a-5p in RA-FLS and to investigate the role of miR-26a-5p in RA. The altered expression of miR-26a-5p in RA-FLS was screened by microarray analysis and confirmed by quantitative real time PCR. The effect of miR-26a-5p on proliferation, cell cycle, apoptosis, and invasion in RA-FLS were studied. The verification of miR-26a-5p target mRNA and downstream signaling pathway was elucidated by bioinformatics analysis, dual luciferase reporter assay, and western blot. Expression of miR-26a-5p was higher in RA-FLS than in fibroblast-like synoviocytes from osteoarthritis patients and trauma patients. Overexpression of miR-26a-5p RA-FLS promoted cells proliferation, G1/S transition, cells invasion, and resisted apoptosis in RA-FLS, whereas it led to contrary effects when inhibiting the expression of miR-26a-5p. The 3′UTR of tensin homolog (PTEN) was directly targetted by miR-26a-5p and activation of phosphoinositide 3-kinase (PI3K)/AKT pathway was observed when overexpression of miR-26a-5p. Our study suggested that miR-26a-5p has a complementary role in cells proliferation, invasion, and apoptosis of RA-FLS, which may be attributed to its activation effect on PI3K/AKT signaling pathway via targetting PTEN. MiR-26a-5p is likely to be a clinically helpful target for novel therapeutic strategies in RA.

MicroRNA-155 inhibition attenuates endoplasmic reticulum stress-induced cardiomyocyte apoptosis following myocardial infarction via reducing macrophage inflammation

Endoplasmic reticulum stress (ERS)-induced cardiomyocyte apoptosis plays an important role in the pathological process following myocardial infarction (MI). Macrophages that express microRNA-155 (miR-155) mediate cardiac inflammation, fibrosis, and hypertrophy. Therefore, we investigated if miR-155 regulates ERS-induced cardiomyocyte apoptosis after MI using a mouse model, lipopolysaccharide (LPS)-induced rat bone marrow derived macrophages (BMDMs)and hypoxia-induced neonatal rat cardiomyocytes (NRCMs). In vivo, miR-155 levelswere significantly higher in the MI group compared to the sham group. MI increasedmacrophage infiltration, nuclear factor-κB (NF-κB) activation, ERS induced-apoptosis, and SOCS1 expression, all of which were attenuated by the miR-155 antagomir, with the exception of SOCS1 expression. Additionally, post-MI cardiac dysfunction was significantly improved by miR-155 inhibition. In vitro, LPS upregulated miR-155 expression in BMDMs, and the miR-155 antagomir decreased LPS-induced macrophage inflammation and NF-κB pathway activation, but increased expression of SOCS1. Hypoxia increased NF-κB pathway activation, ERS marker expression, and apoptosis in NRCMs. Interestingly, conditioned medium from LPS-induced macrophages in combination with the miR-155 antagomir decreased, while the miR-155 agomir increased, the hypoxia-induced effects in NRCM's. The miR-155 agomir effects were reversed by inhibiting the NF-κB pathway in cardiomyocytes. Moreover, SOCS1 knockdown in LPS-induced macrophages promoted NF-κB pathway activation and ERS-induced cardiomyocyte apoptosis in the hypoxia-induced NRCMs, but the SOCS1-siRNA-induced effects were markedly decreased by miR-155 antagomir treatment. These data suggest that miR-155 inhibition attenuates ERS-induced cardiomyocyte apoptosis after MI via reducing macrophage inflammation through the SOCS1/NF-κB pathway.

MicroRNAs as Potential Pharmaco-targets in Ischemia-Reperfusion Injury Compounded by Diabetes

BACKGROUND

Ischemia-Reperfusion (I/R) injury is the tissue damage that results from re-oxygenation of ischemic tissues. There are many players that contribute to I/R injury. One of these factors is the family of microRNAs (miRNAs), which are currently being heavily studied. This review aims to critically summarize the latest papers that attributed roles of certain miRNAs in I/R injury, particularly in diabetic conditions and dissect their potential as novel pharmacologic targets in the treatment and management of diabetes.

METHODS

PubMed was searched for publications containing microRNA and I/R, in the absence or presence of diabetes. All papers that provided sufficient evidence linking miRNA with I/R, especially in the context of diabetes, were selected. Several miRNAs are found to be either pro-apoptotic, as in the case of miR-34a, miR-144, miR-155, and miR-200, or anti-apoptotic, as in the case of miR-210, miR-21, and miR-146a. Here, we further dissect the evidence that shows diverse cell-context dependent effects of these miRNAs, particularly in cardiomyocytes, endothelial, or leukocytes. We also provide insight into cases where the possibility of having two miRNAs working together to intensify a given response is noted.

CONCLUSIONS

This review arrives at the conclusion that the utilization of miRNAs as translational agents or pharmaco-targets in treating I/R injury in diabetic patients is promising and becoming increasingly clearer.

Inhibition of microRNA-155 attenuates sympathetic neural remodeling following myocardial infarction via reducing M1 macrophage polarization and inflammatory responses in mice

Inflammation plays an important role in sympathetic neural remodeling induced by myocardial infarction (MI). MiR-155 is a vital regulator of inflammatory responses, and macrophage-secreted miR-155 promotes cardiac fibrosis and hypertrophy. However, whether miR-155 influences MI-induced sympathetic neural remodeling is not clear. Therefore, we examined the role of miR-155 in MI-induced sympathetic neural remodeling and the related mechanisms in both an mouse model and in lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages (BMDMs). Our data showed that miR-155 expression was significantly enhanced in the myocardial tissues of MI mice compared to sham mice. Also, MI up-regulated the electrophysiological parameters, M1 macrophage polarization, inflammatory responses, and suppressor of cytokine signaling 1 (SOCS1) expression, which coincided with the increased expression of sympathetic nerve remodeling markers(nerve growth factor, tyrosine hydroxylase and growth-associated protein 43). Except for SOCS1, these proteins were attenuated by miR-155 antagomir. In vitro, LPS-stimulation promoted miR-155 expression in BMDMs. Consistent with the in vivo findings, miR-155 antagomir diminished the LPS-induced M1 macrophage polarization, nuclear factor (NF)-κB activation, and the expression of pro-inflammatory factors and nerve growth factor; but it increased the expression of SOCS1. Inversely, miR-155 agomir significantly potentiated LPS-induced pathophysiological effects in BMDMs. MiR-155 agomir-induced effects were reversed by the NF-κB inhibitor. Mechanistically, treatment with siRNA against SOCS1 augmented the aforementioned LPS-mediated activities, which were antagonized by the addition of miR-155 antagomir. In conclusion, miR-155 inhibition downregulated NGF expression via decreasing M1 macrophage polarization and inflammatory responses dependent on the SOCS1/NF-κB pathway, subsequently diminishing MI-induced sympathetic neural remodeling and ventricular arrhythmias (VAs).

Concordant miRNA and mRNA expression profiles in humans and mice with bladder outlet obstruction

Bladder outlet obstruction (BOO) leads to lower urinary tract symptoms (LUTS) and urodynamic changes of the bladder function. Previously we identified microRNA (miRNA) and mRNA expression profiles associated with different states of BOO-induced LUTD in human patients. Bladder wall remodeling resulting from obstruction is widely studied in animal models of experimentally-induced partial BOO (pBOO). Here we determined the expression profiles of miRNAs and selected mRNAs in pBOO mice and compared the observed changes to human patients. Similar to results from human patients, we observed a down-regulation of smooth muscle-associated miRNAs mmu-miR-1, mmu-miR-143, mmu-miR-145, mmu-miR-486 and mmu-miR-133a in pBOO mouse bladders. Pro-fibrotic miRNAs mmu-miR-142-3p and mmu-miR-21 were up-regulated, and anti-fibrotic miRNA mmu-miR-29c was down-regulated. Pathway analysis in human BOO patients identified TNF-alpha as the top upstream regulator. Although there was evidence of hypertrophic changes in pBOO mice, contrary to human data, we observed no regulation of TNF-responsive genes in the mouse model. Experimentally-induced pBOO in mice led to significant gene expression changes, including alteration of pro-fibrotic mRNAs and miRNAs resembling human BOO patients. Gene expression changes were also validated in a mouse model of bladder inflammation. Lack of evidence of TNF-alpha-induced miRNA and mRNA regulation might indicate a different pathophysiological mechanism of organ remodeling in pBOO model compared to the human disease.

Alteration in microRNA-155 level correspond to severity of coronary heart disease

Cardiovascular diseases are a consequence of genetic and epigenetic interactions. Inflammation contributes toward the initiation and progression of atherosclerotic lesions. Previous studies have shown that microRNA (miR) 155 plays a role in cardiovascular disease, including the prevention of inflammatory infiltration, regulation of autophagy, and participation of immunoreactions. However, the change of miR-155 level in the development of atherosclerosis remains to be determined. The initial objective of this study was that CHD patients would have altered serum miR-155 level. We also aim to identify whether circulating miR-155 content could be used as a predictor for severity of coronary atherosclerosis. Sample was collected from 300 CHD patients and 100 controls. Quantitative real-time PCR analysis was utilized on RNA isolated from plasma. Expression of miR-155 was identified on the basis of the quartiles of the Gensini score, and association between the microRNA and CHD was analyzed. CHD patients had higher miR-155 level in comparison to controls (p < .001), and the miRNA content significantly increased following an increasing Gensini score (p < .001). Gensini score was significantly associated with miR-155 expression (r = 0.6124, p < .001). Our findings suggest that interaction between circulating miR-155 expressions with classical risk factors of atherosclerotic lesions, and serum miR-155 content may serve as a novel biomarker for evaluating severity of CHD.

Therapeutic Approaches and Role of ncRNAs in Cardiovascular Disorders and Insulin Resistance

Diseases resulting from alterations in gene expressions through mutations in the genes or through changes in the gene expression regulation could be identified through the analysis of RNA expressions. ncRNAs play a significant role in regulation of the gene expression by controlling the expression levels of the coding RNAs and other cellular processes. Discoveries have shown that the human genome is encoded with sequences responsible for the transcription of thousands of ncRNAs. Even though the studies conducted on ncRNAs are still at initial stages, facts established so far display biomarkers that confirm their relationship with certain diseases such as cancers, cardiovascular diseases, and insulin resistance. These studies have been facilitated with high throughput modern sequencing techniques such as microarrays and RNA sequencing. The data obtained through the above analysis are processed with the aid of existing databases, to deduce conclusions on different diagnostic biomarkers and therapeutic targets for specific diseases. This review focuses on the association of ncRNAs in disease prediction, focusing mainly on cardiovascular diseases and disorders caused by insulin resistance. The report also analyzes regulatory functions of ncRNAs and novel approaches used in disease therapeutics.

Suppression of microRNA-135b-5p protects against myocardial ischemia/reperfusion injury by activating JAK2/STAT3 signaling pathway in mice during sevoflurane anesthesia

The study aims to explore the effects of miR-135b-5p on myocardial ischemia/reperfusion (I/R) injuries by regulating Janus protein tyrosine kinase 2 (JAK2)/signal transducer and activator of transcription (STAT) signaling pathway by mediating inhalation anesthesia with sevoflurane. A sum of 120 healthy Wistar male mice was assigned into six groups. Left ventricular ejection fraction (LVEF) and left ventricular shortening fraction (LVSF) were detected. Cardiomyocyte apoptosis was determined by terminal dexynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) assay. MiR-135b-5p expression, mRNA and protein expression of p-STAT3, p-JAK2, STAT3, JAK2, B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X protein B (Bax) were detected by quantitative real-time PCR (qRT-PCR) and Western blotting. Target relationship between miR-135b-5p and JAK2 was confirmed by dual-luciferase reporter assay. The other five groups exhibited increased cardiomyocyte necrosis, apoptosis, miR-135b-5p and Bax expression, mRNA expression of JAK2 and STAT3, and protein expression of p-STAT3 and p-JAK2 compared with the sham group, but showed decreased LVEF, LVFS, and Bcl-2 expression. Compared with the model and AG490 + Sevo groups, the Sevo, inhibitor + Sevo and inhibitor + AG490 + Sevo groups displayed reduced cardiomyocyte necrosis, apoptosis, miR-135b-5p and Bax expression, but displayed elevated mRNA expression of JAK2 and STAT3, protein expression of p-STAT3 and p-JAK2, LVEF, LVFS and Bcl-2 expression. Compared with the Sevo and inhibitor + AG490 + Sevo groups, the AG490 + Sevo group showed decreased LVEF, LVFS, Bcl-2 expression, mRNA expressions of JAK2 and STAT3, and protein expressions of p-STAT3 and p-JAK2, but increased cardiomyocyte necrosis, apoptosis, and Bax expressions. MiR-135b-5p negatively targetted JAK2. Inhibition of miR-135b-5p can protect against myocardial I/R injury by activating JAK2/STAT3 signaling pathway through mediation of inhalation anesthesia with sevoflurane.