Inflammation-Related MicroRNAs Are Associated with Plaque Stability Calculated by IVUS in Coronary Heart Disease Patients

Exosomal miRNA-21-5p and miRNA-21-3p as key biomarkers of myocardial infarction

Objective

Coronary artery disease (CAD) is a debilitating condition that can lead to myocardial infarction (MI). Exosomal miRNAs (exo-miRNA) can be diagnostic biomarkers for detecting MI. Here, we conduct a study to evaluate the efficacy of exo-miRNA-21-5p/3p for early detection of MI.

Methods

A total of 135 CAD patients and 150 healthy subjects participated in this study. Additionally, we randomly divided 26 male Wistar rats (12 weeks old) into two groups: control and induced MI. Angiographic images were used to identify patients and healthy individuals of all genders. In the following, serum exosomes were obtained, and exo-miRNA-21-5p/3p was measured by reverse-transcriptase polymerase chain reaction.

Results

We observed an upregulation of exo-miRNA-21-5p/3p in CAD patient and MI-induced animal groups compared to controls. Analysis of the ROC curves defined 82% and 88% of the participants' exo-miRNA-21-5p and exo-miRNA-21-3p diagnostic power, respectively, which in the animal model was 92 and 82.

Conclusion

This study revealed that the mean expression levels of exo-miRNA-21-5p/3p were significantly increased in CAD patients and animal models of induced MI. Also, these results are associated with the atherogenic lipid profile of CAD patients, which may play an important role in the progression of the disease. Therefore, they can be considered as novel biomarkers.

MicroRNA-155 and exosomal microRNA-155: Small pieces in the cardiovascular diseases puzzle

MicroRNAs (miRs, miRNAs) are known to have a part in various human illnesses, such as those related to the heart. One particular miRNA, miR-155, has been extensively studied and has been found to be involved in hematopoietic lineage differentiation, immunity, viral infections, inflammation, as well as vascular remodeling. These processes have all been connected to cardiovascular diseases, including heart failure, diabetic heart disease, coronary artery disease, and abdominal aortic aneurysm. The impacts of miR-155 depend on the type of cell it is acting on and the specific target genes involved, resulting in different mechanisms of disease. Although, the exact part of miR-155 in cardiovascular illnesses is yet not fully comprehended, as some studies have shown it to promote the development of atherosclerosis while others have shown it to prevent it. As a result, to comprehend the underlying processes of miR-155 in cardiovascular disorders, further thorough study is required. It has been discovered that exosomes that could be absorbed by adjacent or distant cells, control post-transcriptional regulation of gene expression by focusing on mRNA. Exosomal miRNAs have been found to have a range of functions, including participating in inflammatory reactions, cell movement, growth, death, autophagy, as well as epithelial-mesenchymal transition. An increasing amount of research indicates that exosomal miRNAs are important for cardiovascular health and have a major role in the development of a number of cardiovascular disorders, including pulmonary hypertension, atherosclerosis, acute coronary syndrome, heart failure, and myocardial ischemia-reperfusion injury. Herein the role of miR-155 and its exosomal form in heart diseases are summarized.

miRNAs in Heart Development and Disease

Cardiovascular diseases (CVD) are a group of disorders that affect the heart and blood vessels. They include conditions such as myocardial infarction, coronary artery disease, heart failure, arrhythmia, and congenital heart defects. CVDs are the leading cause of death worldwide. Therefore, new medical interventions that aim to prevent, treat, or manage CVDs are of prime importance. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the posttranscriptional level and play important roles in various biological processes, including cardiac development, function, and disease. Moreover, miRNAs can also act as biomarkers and therapeutic targets. In order to identify and characterize miRNAs and their target genes, scientists take advantage of computational tools such as bioinformatic algorithms, which can also assist in analyzing miRNA expression profiles, functions, and interactions in different cardiac conditions. Indeed, the combination of miRNA research and bioinformatic algorithms has opened new avenues for understanding and treating CVDs. In this review, we summarize the current knowledge on the roles of miRNAs in cardiac development and CVDs, discuss the challenges and opportunities, and provide some examples of recent bioinformatics for miRNA research in cardiovascular biology and medicine.

Associations between circulating microRNAs and lipid-rich coronary plaques measured with near-infrared spectroscopy

Lipid-rich coronary atherosclerotic plaques often cause myocardial infarction (MI), and circulating biomarkers that reflect lipid content may predict risk of MI. We investigated the association between circulating microRNAs (miRs) are lipid-rich coronary plaques in 47 statin-treated patients (44 males) with stable coronary artery disease undergoing percutaneous coronary intervention. We assessed lipid content in non-culprit coronary artery lesions with near-infrared spectroscopy and selected the 4 mm segment with the highest measured lipid core burden index (maxLCBI_4mm). Lipid-rich plaques were predefined as a lesion with maxLCBI_4mm ≥ 324.7. We analyzed 177 circulating miRs with quantitative polymerase chain reaction in plasma samples. The associations between miRs and lipid-rich plaques were analyzed with elastic net. miR-133b was the miR most strongly associated with lipid-rich coronary plaques, with an estimated 18% increase in odds of lipid-rich plaques per unit increase in miR-133b. Assessing the uncertainty by bootstrapping, miR-133b was present in 82.6% of the resampled dataset. Inclusion of established cardiovascular risk factors did not attenuate the association. No evidence was found for an association between the other analyzed miRs and lipid-rich coronary plaques. Even though the evidence for an association was modest, miR-133b could be a potential biomarker of vulnerable coronary plaques and risk of future MI. However, the prognostic value and clinical relevance of miR-133b needs to be assessed in larger cohorts.

Role of miR-143 and miR-146 in Risk Evaluation of Coronary Artery Diseases in Autopsied Samples

Coronary artery disease (CAD) is a common and fatal cardiovascular disease. Among known CAD risk factors, miRNA polymorphisms, such as Has-miR-143 (rs41291957 C>G) and Has-miR-146a (rs2910164 G>A), have emerged as important genetic markers of CAD. Despite many genetic association studies in multiple populations, no study assessing the association between CAD risk and SNPs of miR-143 and miR-146 was documented in the Japanese people. Therefore, using the TaqMan SNP assay, we investigated two SNP genotypes in 151 subjects with forensic autopsy-proven CAD. After pathological observation, we used ImageJ software to assess the degree of coronary artery atresia. Moreover, the genotypes and miRNA content of the two groups of samples with atresia <10% and >10% were analyzed. The results showed that the CC genotype of rs2910164 was more frequent in patients with CAD than in controls, which was associated with the risk of CAD in the study population. However, Has-miR-143 rs41291957 genotype did not show a clear correlation with the risk of CAD.

Differential Expression of Peripheral Circulating MicroRNA-146a Between Patients with Atherosclerotic Vulnerable Plaque and Stable Plaque

Atherosclerotic plaque rupture and subsequent cardiovascular complications threaten the population's health worldwide. The polymorphism of miR-146a rs2910164 was significantly associated with the risk of vulnerable plaques. However, it remains unclear whether the circulating miR-146a is differentially expressed in stable and vulnerable plaques and thus, serves as a potential biomarker.This study aims to analyze the differential expression of circulating miR-146a between patients with stable and vulnerable plaques to explore the potential molecular mechanisms.Public databases were searched from their inception up to November 2022. A study reporting the specific circulating miR-146a levels between patients with stable and vulnerable plaques was included. The study quality was assessed using the modified genetic 8-stars Newcastle-Ottawa scale. The differential expression levels of miR-146a were evaluated using the standardized mean difference (SMD).Eight studies with 978 patients were included and analyzed. The results showed that miR-146a expression levels were significantly higher in the vulnerable plaque population than in the stable plaque population (SMD: 1.91; 95% confidence interval: 1.35, 2.47; P < 0.01). A similar statistical significance was found in subgroup analyses regarding sample source, disease type, and vulnerable plaque characteristics. Sensitivity analysis suggested the robustness of the results. Analysis of downstream genes suggested that miR-146a-targeted regulation of ACTN4, SARM1, and ULK2 may affect intraplaque hemorrhage.Patients with vulnerable plaque have higher circulating miR-146a levels than those with stable plaque. However, based on the limitations of this study, high-quality studies are still needed to confirm the results.

Associations between circulating microRNAs and coronary plaque characteristics: potential impact from physical exercise

Background and aims MicroRNAs (miRs) are involved in different steps in the development of atherosclerosis and are proposed as promising biomarkers of coronary artery disease (CAD). We hypothesized that circulating levels of miRs were associated with coronary plaque components assessed by radiofrequency intravascular ultrasound (RF-IVUS) before and after aerobic exercise intervention. Methods 31 patients with CAD treated with percutaneous coronary intervention (PCI) previously included in a randomized trial with aerobic interval training (AIT) or moderate continuous training (MCT) as post-PCI intervention were included. Coronary plaque characteristics by grayscale and RF-IVUS and predefined circulating candidate miRs in plasma were analysed at baseline and follow-up. Associations between miRs and coronary plaque composition, and the potential effect from exercise, were analysed using linear regression. Results Circulating levels of miR-15a-5p, miR-30e-5p, miR-92a-3p, miR-199a-3p, miR-221-3p, and miR-222-3p were associated with baseline coronary necrotic core volume. Following exercise intervention, decreased levels of miR-15a-5p, miR-93-5p, and miR-451a, and increased levels of miR-146a-5p were associated with an observed regression of coronary plaque burden. A mirPath prediction tool identified that genes regulated by miR-15a-5p, miR-199a-3p, and miR-30e-5p were significantly overrepresented in pathways related to fatty acid biosynthesis and fatty acid metabolism. Conclusion This exploratory study demonstrated six miRs associated with coronary necrotic core, a marker of plaque vulnerability. In addition, changes in four miRs were associated with a regression of coronary plaque burden following exercise intervention. These novel findings may identify potential future biomarkers of CAD and coronary plaque composition.

miR-146a contributes to atherosclerotic plaque stability by regulating the expression of TRAF6 and IRAK-1

BACKGROUND

Atherosclerosis is a chronic inflammatory disease. The vulnerable plaque of atherosclerotic can lead to the development of many diseases including acute coronary syndrome and coronary heart disease. It is well known that miR-146a is the key brake miRNA of the inflammatory signal transduction pathway. However, the effect of miR-146a on the stability of atherosclerotic plaque remains to be elucidated.

METHODS AND RESULTS

We constructed animal models of atherosclerosis and foam cell models, and overexpressed and knocked-down miR-146a in models. After staining with Hematoxylin-Eosin (HE), Oil Red O, immunocytochemistry (IHC) and Sirius Red, we used the proportion of (Lipids area + Macrophage area) and (SMCs area + collagen area) to evaluate atherosclerotic plaque stability. TUNEL and flow cytometry were performed to detect the apoptosis level of macrophages. Levels of inflammatory factors were detected via ELISA assay. The results showed that miR-146a, IRAK1 and TRAF6 were abnormally expressed in plaques of atherosclerotic animals. Overexpression of miR-146a contributed to the stability of plaques that inhibited plaque formation, macrophage apoptosis and levels of pro-inflammatory factors. The Dual-luciferase reporter gene assay, IF and FISH were used to verify the regulatory mechanism of miR-146a on IRAK1 and TRAF6. We found that IRAK1 and TRAF6 promoted lipid uptake, apoptosis, and release of pro-inflammatory factors of RAW264.7 macrophages, whereas miR-146a restored RAW264.7 macrophages phenotype by inhibiting IRAK1 and TRAF6 expression.

CONCLUSIONS

We display for the first time that miR-146a inhibits the formation of foam cells, RAW264.7 macrophage apoptosis and pro-inflammatory reaction through negative regulation of IRAK1 and TRAF6 expression, thereby enhancing the stability of atherosclerotic plaques.

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.

Increased plasma miR-146a levels are associated with subclinical atherosclerosis in newly diagnosed type 2 diabetes mellitus

AIMS

The association between circulating miR-146a and subclinical atherosclerosis in type 2 diabetes mellitus (T2DM) remains poorly understood. This study aimed to investigate the correlation between plasma miR-146a levels and subclinical atherosclerosis as measured by the carotid intima-media thickness (CIMT) and brachial-ankle pulse wave velocity (baPWV) in patients with newly diagnosed T2DM.

METHODS

We studied 100 patients with newly diagnosed T2DM. Subclinical atherosclerosis was defined as a thickened CIMT (≥1.0 mm) and high baPWV defined as a value greater than the 75th percentile. Plasma miR-146a levels and metabolic parameters were measured.

RESULTS

Patients with thickened CIMT had higher plasma miR-146a levels than those without thickened CIMT (3.36 ± 1.32 vs 1.38 ± 1.11, P < 0.001). Patients in the high baPWV group had higher plasma miR-146a levels than those in the normal baPWV group (3.43 ± 1.32 vs 1.98 ± 1.48, P < 0.001). Both CIMT (β = 0.569, P < 0.001) and baPWV (β = 0.274, P = 0.001) positively correlated with plasma miR-146a levels after adjustment for confounding factors by multiple stepwise regression. On binary logistic regression, plasma miR-146a level was an independent risk factor for thickened CIMT (OR = 3.890, 95% CI 1.415-7.698, P = 0.008) and high baPWV (OR = 1.954, 95% CI 1.256-3.040, P = 0.002) after adjustment for established cardiovascular risk factors. The area under the receiver operating characteristics curve (AUROC) of plasma miR-146a level for predicting thickened CIMT was 0.795 (95%CI 0.708-0.883, P < 0.001) and for predicting high baPWV was 0.773 (95%CI 0.679-0.867, P < 0.001).

CONCLUSION

Plasma miR-146a levels correlate with CIMT and baPWV and could act as a biomarker for early diagnosis and as a therapeutic target for atherosclerosis in T2DM.

Puerarin alleviates cisplatin-induced acute renal damage and upregulates microRNA-31-related signaling

Cisplatin (DDP) is a commonly used chemotherapy drug; however, the side effects associated with its use, particularly acute kidney injury (AKI), limit its clinical application. Puerarin is a natural flavonoid extracted from the Chinese medical herb Radix puerariae, which has been reported to alleviate DDP-induced nephrotoxicity. However, the mechanisms underlying puerarin regulation on microRNA (miR)-31-mediated signaling pathways in AKI remain unknown. Thus, the present study aimed to investigate the function of puerarin in a DDP-induced AKI rat model via reverse transcription-quantitative PCR and western blot analyses. The results demonstrated that DDP upregulated the levels of miR-31 in a concentration-dependent manner, both in vitro and in vivo. Furthermore, DDP significantly increased blood urea nitrogen and malondialdehyde content, serum creatinine and histopathological changes, while significantly decreasing the expression levels of superoxide dismutase, catalase and glutathione S-transferase in kidney tissues. TUNEL and western blot analyses indicated that DDP increased the expression levels of apoptotic proteins and affected the Numb/Notch1 signaling pathway, which is downstream of miR-31. The effects induced by DDP were counteracted following treatment with puerarin. Taken together, the results of the present study suggest that puerarin exhibits a renal protective effect against DDP-induced AKI by upregulating miR-31 expression and inhibiting the Numb/Notch1 signaling pathway.

Emerging Challenges of Radiation-Associated Cardiovascular Dysfunction (RACVD) in Modern Radiation Oncology: Clinical Practice, Bench Investigation, and Multidisciplinary Care

Radiotherapy (RT) is a crucial treatment modality in managing cancer patients. However, irradiation dose sprinkling to tumor-adjacent normal tissues is unavoidable, generating treatment toxicities, such as radiation-associated cardiovascular dysfunction (RACVD), particularly for those patients with combined therapies or pre-existing adverse features/comorbidities. Radiation oncologists implement several efforts to decrease heart dose for reducing the risk of RACVD. Even applying the deep-inspiration breath-hold (DIBH) technique, the risk of RACVD is though reduced but still substantial. Besides, available clinical methods are limited for early detecting and managing RACVD. The present study reviewed emerging challenges of RACVD in modern radiation oncology, in terms of clinical practice, bench investigation, and multidisciplinary care. Several molecules are potential for serving as biomarkers and therapeutic targets. Of these, miRNAs, endogenous small non-coding RNAs that function in regulating gene expression, are of particular interest because low-dose irradiation, i.e., 200 mGy (one-tenth of conventional RT daily dose) induces early changes of pro-RACVD miRNA expression. Moreover, several miRNAs, e.g., miR-15b and miR21, involve in the development of RACVD, further demonstrating the potential bio-application in RACVD. Remarkably, many RACVDs are late RT sequelae, characterizing highly irreversible and progressively worse. Thus, multidisciplinary care from oncologists and cardiologists is crucial. Combined managements with commodities control (such as hypertension, hypercholesterolemia, and diabetes), smoking cessation, and close monitoring are recommended. Some agents show abilities for preventing and managing RACVD, such as statins and angiotensin-converting enzyme inhibitors (ACEIs); however, their real roles should be confirmed by further prospective trials.