Comparative microRNA profiling in relation to urinary albumin excretion in newly diagnosed hypertensive patients

MicroRNAs: The Missing Link between Hypertension and Periodontitis?

Cardiovascular diseases are the leading cause of death worldwide, and arterial hypertension is a recognized cardiovascular risk factor that is responsible for high morbidity and mortality. Arterial hypertension is the result of an inflammatory process that results in the remodeling and thickening of the vascular walls, which is associated with an immunological response. Previous studies have attempted to demonstrate the relationship between oral disease, inflammation, and the development of systemic diseases. Currently, the existence of an association between periodontitis and hypertension is a controversial issue because the underlying pathophysiological processes and inflammatory mechanisms common to both diseases are unknown. This is due to the fact that periodontitis is a chronic inflammatory disease that affects the interface of teeth and surrounding tissues. However, the most likely explanation for understanding this association is related to low-grade chronic inflammation. An initial path in the study of the relationship between the mentioned pathologies is the possibility of an epigenetic influence, mediated by noncoding RNAs as microRNAs. Thus, in the present review we describe the role of microRNAs related to arterial hypertension and/or periodontitis. In addition, we identified 13 common microRNAs between periodontitis and hypertension. According to the predictions of the DIANA-mirPath program, they can regulate genes involved in 52 signaling pathways.

Potential roles of circulatory microRNAs in the onset and progression of renal and cardiac diseases: a focussed review for clinicians

The signalling mechanisms involving the kidney and heart are a niche of networks causing pathological conditions inducing inflammation, reactive oxidative species, cell apoptosis, and organ dysfunction during the onset of clinical complications. The clinical manifestation of the kidney and heart depends on various biochemical processes that influence organ dysfunction coexistence through circulatory networks, which hold utmost importance. The cells of both organs also influence remote communication, and evidence states that it may be explicitly by circulatory small noncoding RNAs, i.e. microRNAs (miRNAs). Recent developments target miRNAs as marker panels for disease diagnosis and prognosis. Circulatory miRNAs expressed in renal and cardiac disease can reveal relevant information about the niche of networks and gene transcription and regulated networks. In this review, we discuss the pertinent roles of identified circulatory miRNAs regulating signal transduction pathways critical in the onset of renal and cardiac disease, which can hold promising future targets for clinical diagnostic and prognostic purposes.

Extracellular Vesicles in Essential Hypertension: Hidden Messengers

PURPOSE OF REVIEW

Hypertension affects about half of all Americans, yet in the vast majority of cases, the factors causing the hypertension cannot be clearly delineated. Developing a more precise understanding of the molecular pathogenesis of HTN and its various phenotypes is therefore a pressing priority. Circulating and urinary extracellular vesicles (EVs) are potential novel candidates as biomarkers and bioactivators in HTN. EVs are a heterogeneous population of small membrane fragments shed from various cell types into various body fluids. As EVs carry protein, RNA, and lipids, they also play a role as effectors and novel cell-to-cell communicators. In this review, we discuss the diagnostic, functional, and regenerative role of EVs in essential HTN and focus on EV protein and RNA cargo as the most extensively studied EV cargo.

RECENT FINDINGS

The field of EVs in HTN is still a young one and earlier studies have not used the novel EV detection tools currently available. More rigor and transparency in EV research are needed. Current data suggest that EVs represent potential novel biomarkers in HTN. EVs correlate with HTN severity and possibly end-organ damage. However, it has yet to be discerned which specific subtype(s) of EV reflects best HTN pathophysiology. Evolving studies are also showing that EVs might be novel regulators in vascular and renal tubular function and also be therapeutic. RNA in EVs has been studied in the context of hypertension, largely in the form of studies of miRNA, which are reviewed herein. Beyond miRNAs, mRNA in urinary EVs changed in response to sodium loading in humans. EVs represent promising novel biomarkers and bioactivators in essential HTN. Novel tools are being developed to apply more rigor in EV research including more in vivo models and translation to humans.

Blood microRNA 202-3p associates with the risk of essential hypertension by targeting soluble ST2

MicroRNA (miR)-202-3p has attracted a great deal of attention in the fields of oncology, gynecology, and metabolic disorders. However, its role in cardiovascular diseases remains to be clarified. We previously found that disruption of miR-202-3p mediated regulation of expression of soluble (s)ST2, a decoy receptor for interleukin (IL)-33, promotes essential hypertension (EH). In the present study, we first measured miR-202-3p expression levels in the blood of 182 EH cases and 159 healthy controls using TaqMan assays. miR-202-3p levels were shown to be significantly higher in EH cases than controls (fold change = 3.58, P<0.001). Logistic regression analysis revealed that higher miR-202-3p expression was associated with an increased occurrence of EH (adjusted odds ratio (OR): 1.57; 95% confidence interval (CI), 1.36-1.82; P<0.001). Addition of miR-202-3p to traditional risk factors showed an additive prediction value for EH. Further functional experiments indicated that miR-202-3p could be induced by angiotensin II (Ang II) and inhibited by Ang II-triggered soluble ST2 (sST2) expression in a negative feedback manner. Moreover, blood miR-202-3p levels were negatively correlated with sST2 expression in vivo. Our study shows that blood miR-202-3p levels were significantly associated with the occurrence of EH. These findings indicate that miR-202-3p exerts a protective role against EH by antagonizing the induction of sST2 by Ang II.

Extracellular vesicles as a novel diagnostic and research tool for patients with HTN and kidney disease

Hypertension (HTN) affects one in three adults in the United States and is a major risk factor for cardiovascular disease and kidney failure. There is emerging evidence that more intense blood pressure lowering reduces mortality in patients with kidney disease who are at risk of cardiovascular disease and progression to end-stage renal disease. However, the ideal blood pressure threshold for patients with kidney disease remains a question of debate. Novel tools to more precisely diagnose HTN, tailor treatment, and predict the risk of end-organ damage such as kidney disease are needed. Analysis of circulating and urinary extracellular vesicles (EVs) and their cargo (protein and RNA) has the potential to identify novel noninvasive biomarkers that can also reflect a specific pathological mechanism of different HTN phenotypes. We will discuss the use of extracellular vesicles as markers of HTN severity and explain their profile change with antihypertensive medicine and potential to detect early end-organ damage. However, more studies with enhanced rigor in this field are needed to define the blood pressure threshold to prevent or delay kidney disease progression and decrease cardiovascular risk.

Endothelial dysfunction in diabetes and hypertension: Role of microRNAs and long non-coding RNAs

The vascular endothelium acts as a barrier between the blood flow and the inner lining of the vessel wall, and it functions as a filtering machinery to filter out any unwanted transfer of materials from both sides (i.e. the blood and the surrounding tissues). It is evident that diseases such as diabetes, obesity, and hypertension disturb the normal endothelial functions in humans and lead to endothelial dysfunction, which may further precede to the development of atherosclerosis. Long non-coding RNAs and micro RNAs both are types of non-coding RNAs which, in the recent years, have increasingly been studied in the pathophysiology of many diseases including diabetes, obesity, cardiovascular diseases, neurological diseases, and others. Recent findings have pointed out important aspects on their relevance to endothelial function as well as dysfunction of the system which may arise from presence of diseases such as diabetes and hypertension. Diabetes or hypertension-mediated endothelial dysfunction show characteristics such as reduced nitric oxide synthesis through suppression of endothelial nitric oxide synthase activity in endothelial cells, reduced sensitivity of nitric oxide in smooth muscle cells, and inflammation - all of which have been either shown to be directly caused by gene regulatory mechanisms of non-coding RNAs or shown to be having a correlation with them. In this review, we aim to discuss such findings on the role of these non-coding RNAs in diabetes or hypertension-associated endothelial dysfunction and the related mechanisms that may pave the way for alleviating endothelial dysfunction and its related complications such as atherosclerosis.

The association of miR-29a with proteinuria in essential hypertension

Recently, miRNAs have emerged as new indirect markers of inflammation that are associated with adverse outcomes in cardiovascular disease. The aim of the study was to evaluate the relationship between miR29a and proteinuria in hypertension. Fifty patients with normal albuminuria, fifty patients with micro-albuminuria, and fifty patients with macro-albuminuria were enrolled. The highest levels of miR-29a and transforming growth factor-β1 (TGF-β1) were observed in the macro-albuminuria group, followed by the micro-albuminuria and the normal albuminuria groups. The level of miR-29a was negatively correlated with the glomerular filtration rate, but was positively correlated with C-reactive protein, TGF-β1, and the urinary albumin to creatinine ratio (UACR). Circulating miR-29a was found to be significantly and independently associated with proteinuria. Our findings showed that miR-29a reflects the pathogenesis of hypertensive nephropathy and may serve as a potential non-invasive marker for detecting early stages of hypertensive nephropathy.

microRNA-21 and hypertension

Hypertension, a multifactorial disease, is a major risk factor for the development of stroke, coronary artery disease, heart failure, and chronic renal failure. However, its underlying cellular and molecular mechanisms remain largely elusive. Numerous studies have shown that microRNAs (miRNAs) are involved in a variety of cellular processes, including cellular proliferation, apoptosis, differentiation, and the development of diseases. microRNA-21 (miR-21), a conserved single-stranded non-coding RNA that is composed of approximately 22 nucleotides, is one of the most intensively studied miRNAs in recent years, and it can regulate gene expression at the post-transcriptional level. miR-21 is expressed in many kinds of tumors and in the cardiovascular system, and it plays an important role in the occurrence and development of cardiovascular diseases. In recent years, more and more evidence indicates that miR-21 plays an important role in hypertension. This article reviews the source, function, and altered levels of miR-21 in hypertension and the role of miR-21 in the pathogenesis of hypertension and target organ damage (TOD). The potential role of miR-21 as a new target for predicting and treating hypertension is also explored.

Urinary miRNA-377 and miRNA-216a as biomarkers of nephropathy and subclinical atherosclerotic risk in pediatric patients with type 1 diabetes

BACKGROUND

Urinary microRNAs (miRNAs) play a role in the pathogenesis of chronic kidney disease (CKD).

AIM

To identify the expression of urinary miR-377 and miR-216a in 50 children and adolescents with type 1 diabetes (T1DM) compared with 50 healthy controls and assess their relation to the degree of albuminuria, glycemic control and carotid intimal thickness (CIMT) as an index of atherosclerosis.

METHODS

Diabetic subjects were divided into normoalbuminuric and microalbuminuric groups according to urinary albumin creatinine ration (UACR). Urinary miRNAs were assessed using real time polymerase chain reaction. CIMT was measured using high resolution carotid ultrasound.

RESULTS

The expression of urinary miR-377 was significantly higher in patients with microalbumiuria (median, 3.8) compared with 2.65 and 0.98 in normoalbuminic patients and healthy controls, respectively (p<0.05). Urinary miR-216a was significantly lower in all patients with type 1 diabetes and the lowest levels were among the microalbumiuric group. Significant positive correlations were found between urinary miR-377 and HbA1C, UACR and CIMT while urinary miR-216a was negatively correlated to these variables.

CONCLUSIONS

Urinary miR-377 and miR-216a can be considered early biomarkers of nephropathy in pediatric type 1 diabetes. Their correlation with CIMT provides insights on the subclinical atherosclerotic process that occurs in diabetic nephropathy.

The Future of "Omics" in Hypertension

Despite decades of research and clinical practice, the pathogenesis of hypertension remains incompletely understood, and blood pressure is often suboptimally controlled. “Omics” technologies allow the description of a large number of molecular features and have the potential to identify new factors that contribute to blood pressure regulation and how they interact. In this review, we focus on the potential of genomics, transcriptomics, proteomics, and metabolomics and explore their roles in unraveling the pathophysiology and diagnosis of hypertension, the prediction of organ damage and treatment response, and monitoring treatment effect. Substantial progress has been made in the area of genomics, in which genome-wide association studies have identified > 50 blood pressure–related, single-nucleotide polymorphisms, and sequencing studies (especially in secondary forms of hypertension) have discovered novel regulatory pathways. In contrast, other omics technologies, despite their ability to provide detailed insights into the physiological state of an organism, have only more recently demonstrated their impact on hypertension research and clinical practice. The majority of current proteomic studies focus on organ damage resulting from hypertension and may have the potential to help us understand the link between blood pressure and organ failure but also serve as biomarkers for early detection of cerebrovascular or coronary disease. Examples include signatures for early detection of left ventricular dysfunction or albuminuria. Metabolomic studies have the potential to integrate environmental and intrinsic factors and are particularly suited to monitor the response to treatment. We discuss examples of omics studies in hypertension and explore the challenges related to these novel technologies.