Circulating Levels of MicroRNAs Associated With Hypertension: A Cross-Sectional Study in Male and Female South African Participants

Circulatory miRNAs in essential hypertension

MicroRNAs (miRNAs) are short non-coding RNAs, that regulate gene-expression at post-transcriptional level. Unlike other RNA species, blood miRNAs circulate in a highly stable form, either within extracellular vesicles or bound to proteins. In recent years, circulatory miRNA profiles have been proposed as potential biomarkers for multitude of pathologies, including essential hypertension. However, the evidence of miRNA biomarker potential is limited, mainly due to the scarcity of profiling studies associating miRNA levels with hypertension. Furthermore, most of these studies have been performed with preselected miRNA pool, limiting their discovery potential. Here, we summarize the results of the unbiased profiling studies and additionally discuss findings from targeted miRNA analysis. Only miR-30e has been found to be associated with hypertension in more than one unbiased study. The targeted analyses highlight the association of miR-1, -21, -34a, -92a, -122, -126, -143, -145, -605, -623, -1299, as well as let-7 and miR-30 families with hypertension. Current literature indicates that some of these miRNAs are involved in hypertension-associated vascular dysfunction and the development of atherosclerosis, suggesting a novel mechanism for cardiovascular disease risk posed by hypertension. All in all, studies associating hypertension with circulatory miRNA profiles are scarce, with several limitations affecting the comparability of the studies. This review discusses the functions and potential mechanisms linking the identified miRNAs to hypertension and underscores the need for further research.

Research hotspots and trends regarding microRNAs in hypertension: a bibliometric analysis

To investigate the research levels, hotspots, and development trends regarding microRNAs in hypertension, this study conducted a visual analysis of studies on miRNA in hypertension based on the Web of Science core collection database using CiteSpace and VOSviewer analysis software along with literature from 2005-2023 as information data. Using citation frequency, centrality, and starting year as metrics, this study analyzed the research objects. It revealed the main research bodies and hotspots and evaluated the sources of literature and the distribution of knowledge from journals and authors. Finally, the potential research directions for miRNAs in hypertension are discussed. The results showed that the research field is in a period of vigorous development, and scholars worldwide have shown strong interest in this research field. A comprehensive summary and analysis of the current research status and application trends will prove beneficial for the advancement of this field.

Circulating MicroRNAs Related to Arterial Stiffness in Adults with HIV Infection

People with HIV (PWH) have an elevated risk of cardiovascular disease compared to those without HIV. This study aimed to investigate the relative serum expression of microRNAs (miRNAs) associated with arterial stiffness, a significant marker of cardiovascular disease. A total of 36 male PWH and 36 people without HIV, matched for age, body mass index, pack years, and dyslipidemia, were included in the study. Participants with a history of hypertension, diabetes mellitus, cardiovascular disease, cancer, or intravenous drug use were excluded. Markers of arterial stiffness, including carotid-femoral pulse wave velocity (cfPWV) and augmentation index adjusted to 75 beats per minute (AIx@75), were measured via applanation tonometry. We analyzed the relative expression of 11 circulating miRNAs using real-time PCR: let-7b-5p, miR-19b-3p, miR-21-5p, miR-29a-3p, miR-126-3p, miR-130a-3p, miR-145-5p, miR-181b-5p, miR-221-3p, miR-222-3p, and miR-223-3p. cfPWV was significantly higher in PWH compared to people without HIV (9.3 vs. 8.6 m/s, p = 0.019), while AIx@75, peripheral, and aortic blood pressures did not differ among groups. The relative expression of circulating miRNAs was significantly higher in PWH compared to controls for let-7b-5p (fold change: 5.24, p = 0.027), miR-21-5p (fold change: 3.41, p < 0.001), miR-126-3p (fold change: 1.23, p = 0.019), and miR-222-3p (fold change: 3.31, p = 0.002). Conversely, the relative expression of circulating miR-19b-3p was significantly lower in PWH (fold change: 0.61, p = 0.049). Among HIV-related factors, the nadir CD4+T-cell count of <200 cells/mm3 was independently associated with the relative expression of circulating let-7b-5p (β = 0.344, p = 0.049), while current non-nucleoside reverse transcriptase inhibitor (NNRTI) treatment was independently associated with the relative expression of circulating miR-126-3p (β = 0.389, p = 0.010). No associations were found between the duration of HIV infection or the duration of ART and the serum miRNA expression. This study highlights a distinct circulating miRNA profile in PWH with higher cfPWV compared to those without HIV, which may contribute to increased arterial stiffness.

Epigenetics of hypertension as a risk factor for the development of coronary artery disease in type 2 diabetes mellitus

Hypertension, a multifaceted cardiovascular disorder influenced by genetic, epigenetic, and environmental factors, poses a significant risk for the development of coronary artery disease (CAD) in individuals with type 2 diabetes mellitus (T2DM). Epigenetic alterations, particularly in histone modifications, DNA methylation, and microRNAs, play a pivotal role in unraveling the complex molecular underpinnings of blood pressure regulation. This review emphasizes the crucial interplay between epigenetic attributes and hypertension, shedding light on the prominence of DNA methylation, both globally and at the gene-specific level, in essential hypertension. Additionally, histone modifications, including acetylation and methylation, emerge as essential epigenetic markers linked to hypertension. Furthermore, microRNAs exert regulatory influence on blood pressure homeostasis, targeting key genes within the aldosterone and renin-angiotensin pathways. Understanding the intricate crosstalk between genetics and epigenetics in hypertension is particularly pertinent in the context of its interaction with T2DM, where hypertension serves as a notable risk factor for the development of CAD. These findings not only contribute to the comprehensive elucidation of essential hypertension but also offer promising avenues for innovative strategies in the prevention and treatment of cardiovascular complications, especially in the context of T2DM.

Unveiling the regulatory role of miRNAs in stroke pathophysiology and diagnosis

Stroke, a major global cause of mortality, leads to a range of problems for those who survive. Besides its brutal events, stroke also tends to have a characteristic of recurrence, making it a complex disease involving intricate regulatory networks. One of the major cellular regulators is the non-coding RNAs (ncRNA), specifically microRNAs (miRNAs), thus the possible functions of miRNAs in the pathogenesis of stroke are discussed as well as the possibility of using miRNA-based therapeutic approaches. Firstly, the molecular mechanisms by which miRNAs regulate vital physiological processes, including synaptic plasticity, oxidative stress, apoptosis, and the integrity of the blood-brain barrier (BBB) are reviewed. The miRNA indirectly impacts stroke outcomes by regulating BBB function and angiogenesis through the targeting of transcription factors and angiogenic factors. In addition, the tendency for some miRNAs to be upregulated in response to hypoxia, which is a prevalent phenomenon in stroke and various neurological disorders, highlights the possibility that it controls hypoxia-inducible factor (HIF) signaling and angiogenesis, thereby influencing the integrity of the BBB as examples of the discussed mechanisms. Furthermore, this review explores the potential therapeutic targets that miRNAs may offer for stroke recovery and highlights their promising capacity to alleviate post-stroke complications. This review provides researchers and clinicians with valuable resources since it attempts to decipher the complex network of miRNA-mediated mechanisms in stroke. Additionally, the review addresses the interplay between miRNAs and stroke risk factors as well as clinical applications of miRNAs as diagnostic and prognostic markers.

Summary of Known Genetic and Epigenetic Modification Contributed to Hypertension

Hypertension is a multifactorial disease due to a complex interaction among genetic, epigenetic, and environmental factors. Characterized by raised blood pressure (BP), it is responsible for more than 7 million deaths per annum by acting as a leading preventable risk factor for cardiovascular disease. Reports suggest that genetic factors are estimated to be involved in approximately 30 to 50% of BP variation, and epigenetic marks are known to contribute to the initiation of the disease by influencing gene expression. Consequently, elucidating the genetic and epigenetic mediators associated with hypertension is essential for better discernment of its pathophysiology. By deciphering the unprecedented molecular hypertension basis, it could help to unravel an individual's inclination towards hypertension which eventually could result in an arrangement of potential strategies for prevention and therapy. In the present review, we discuss known genetic and epigenetic drivers that contributed to the hypertension development and summarize the novel variants that have currently been identified. The effect of these molecular alterations on endothelial function was also presented.

The Role of MicroRNA-126 in Atherosclerotic Cardiovascular Diseases

Atherosclerotic cardiovascular diseases remain the leading cause of morbidity and mortality worldwide despite all efforts made towards their management. Other than targeting the traditional risk factors for their development, scientific interest has been shifted towards epigenetic regulation, with microRNAs (miRs) being at the forefront. MiR-126, in particular, has been extensively studied in the context of cardiovascular diseases. Downregulated expression of this miR has been associated with highly prevalent cardiovascular risk factors such as arterial hypertension and diabetes mellitus. At the same time, its diagnostic and prognostic capability concerning coronary artery disease is still under investigation, with up-to-date data pointing towards a dysregulated expression in a stable disease state and acute myocardial infarction. Moreover, a lower expression of miR-126 may indicate a higher disease complexity, as well as an increased risk for future major adverse cardiac and cerebrovascular events. Ultimately, overexpression of miR-126 may emerge as a novel therapeutic target in atherosclerotic cardiovascular diseases due to its potential in promoting therapeutic angiogenesis and anti-inflammatory effects. However, the existing challenges in miR therapeutics need to be resolved before translation to clinical practice.

The key roles of non-coding RNAs in the pathophysiology of hypertension

Hypertension is a multifactorial condition in which several genetic and environmental elements contribute. Recent investigations have revealed contribution of non-coding region of the transcriptome in this trait. CDKN2B-AS1, AK098656, MEG3, H19, PAXIP1-AS1, TUG1, GAS5, CASC2 and CPS1-IT are among long non-coding RNAs participating in the pathophysiology of hypertension. Several miRNAs have also been found to be implicated in this disorder. miR-296, miR-637, miR-296, miR-637, hsa-miR-361-5p, miR-122-5p, miR-199a-3p, miR-208a-3p, miR-423-5p, miR-223-5p and miR-140-5p are among dysregulated miRNAs in this condition whose application as diagnostic biomarkers for hypertension has been evaluated. Finally, hsa-circ-0005870, hsa_circ_0037911 and hsa_circ_0014243 are examples of dysregulated circular RNAs in hypertensive patients. In the current review, we describe the role of these non-coding RNAs in the pathophysiology of hypertension.

MicroRNA-126-3p/5p and Aortic Stiffness in Patients with Turner Syndrome

Background: Turner Syndrome (TS) is a relatively rare X-chromosomal disease with increased cardiovascular morbidity and mortality. This study aimed to identify whether the circulating miR-126-3p/5p are involved in the pathophysiology of vascular dysfunction in TS. Methods: Using the RT-qPCR, the abundance levels of miR-126-3p and miR-126-5p were determined in 33 TS patients and 33 age-matched healthy volunteers (HVs). Vascular screening, including the assessment of blood pressure, pulse wave velocity, augmentation index, aortic deformation, arterial distensibility, and arterial elastance, was conducted in TS patients and HVs. Results: The abundance levels of miR-126-3p and miR-126-5p were significantly higher in TS patients compared to HVs (p < 0.0001). Within the TS cohort, miR-126-3p/5p correlated significantly with aortic deformation (r = 0.47, p = 0.01; r = 0.48, p < 0.01) and arterial distensibility (r = 0.55, p < 0.01; r = 0.48, p < 0.01). In addition, a significant negative correlation was demonstrated between miR-126-3p and arterial elastance (r = −0.48, p = 0.01). The receiver operating characteristic analysis showed that miR-126-3p and miR-126-5p separated the tested groups with high sensitivity and specificity. Conclusions: The abundance levels of miR-126-3p and miR-126-5p were significantly higher in TS patients compared to HVs. Within the TS cohort, a lower abundance level of miR-126-3p and miR-126-5p was linked with a significantly higher aortic stiffness.

Biofluid Specificity of Long Non-Coding RNA Profile in Hypertension: Relevance of Exosomal Fraction

Non-coding RNA (ncRNA)-mediated targeting of various genes regulates the molecular mechanisms of the pathogenesis of hypertension (HTN). However, very few circulating long ncRNAs (lncRNAs) have been reported to be altered in essential HTN. The aim of our study was to identify a lncRNA profile in plasma and plasma exosomes associated with urinary albumin excretion in HTN by next-generation sequencing and to assess biological functions enriched in response to albuminuria using GO and KEGG analysis. Plasma exosomes showed higher diversity and fold change of lncRNAs than plasma, and low transcript overlapping was found between the two biofluids. Enrichment analysis identified different biological pathways regulated in plasma or exosome fraction, which were implicated in fatty acid metabolism, extracellular matrix, and mechanisms of sorting ncRNAs into exosomes, while plasma pathways were implicated in genome reorganization, interference with RNA polymerase, and as scaffolds for assembling transcriptional regulators. Our study found a biofluid specific lncRNA profile associated with albuminuria, with higher diversity in exosomal fraction, which identifies several potential targets that may be utilized to study mechanisms of albuminuria and cardiovascular damage.