The endothelial-specific microRNA miR-126 governs vascular integrity and angiogenesis

Impacts of circulating microRNAs in exercise-induced vascular remodeling

Cardiovascular adaptation underlies all athletic training modalities, with a variety of factors contributing to overall response during exercise-induced stimulation. In this regard the role of circulating biomarkers is a well-established and invaluable tool for monitoring cardiovascular function. Specifically, novel biomarkers such as circulating cell free DNA and RNA are now becoming attractive tools for monitoring cardiovascular function with the advent of next generation technologies that can provide unprecedented precision and resolution of these molecular signatures, paving the way for novel diagnostic and prognostic avenues to better understand physiological remodeling that occurs in trained versus untrained states. In particular, microRNAs are a species of regulatory RNAs with pleiotropic effects on multiple pathways in tissue-specific manners. Furthermore, the identification of cell free microRNAs within peripheral circulation represents a distal signaling mechanism that is just beginning to be explored via a diversity of molecular and bioinformatic approaches. This article provides an overview of the emerging field of sports/performance genomics with a focus on the role of microRNAs as novel functional diagnostic and prognostic tools, and discusses present knowledge in the context of athletic vascular remodeling. This review concludes with current advantages and limitations, touching upon future directions and implications for applying contemporary systems biology knowledge of exercise-induced physiology to better understand how disruption can lead to pathology.

Atrial myxomas arise from multipotent cardiac stem cells

Aims

Cardiac myxomas usually develop in the atria and consist of an acid-mucopolysaccharide-rich myxoid matrix with polygonal stromal cells scattered throughout. These human benign tumours are a valuable research model because of the rarity of cardiac tumours, their clinical presentation and uncertain origin. Here, we assessed whether multipotent cardiac stem/progenitor cells (CSCs) give rise to atrial myxoma tissue.

Methods and results

Twenty-three myxomas were collected and analysed for the presence of multipotent CSCs. We detected myxoma cells positive for c-kit (c-kit^pos) but very rare Isl-1 positive cells. Most of the c-kit^pos cells were blood lineage-committed CD45^pos/CD31^pos cells. However, c-kit^pos/CD45^neg/CD31^neg cardiac myxoma cells expressed stemness and cardiac progenitor cell transcription factors. Approximately ≤10% of the c-kit^pos/CD45^neg/CD31^neg myxoma cells also expressed calretinin, a characteristic of myxoma stromal cells. In vitro, the c-kit^pos/CD45^neg/CD31^neg myxoma cells secrete chondroitin-6-sulfate and hyaluronic acid, which are the main components of gelatinous myxoma matrix in vivo. In vitro, c-kit^pos/CD45^neg/CD31^neg myxoma cells have stem cell properties being clonogenic, self-renewing, and sphere forming while exhibiting an abortive cardiac differentiation potential. Myxoma-derived CSCs possess a mRNA and microRNA transcriptome overall similar to normal myocardium-derived c-kit^pos/CD45^neg/CD31^negCSCs , yet showing a relatively small and relevant fraction of dysregulated mRNA/miRNAs (miR-126-3p and miR-335-5p, in particular). Importantly, myxoma-derived CSCs but not normal myocardium-derived CSCs, seed human myxoma tumours in xenograft’s in immunodeficient NOD/SCID mice.

Conclusion

Myxoma-derived c-kit^pos/CD45^neg/CD31^neg CSCs fulfill the criteria expected of atrial myxoma-initiating stem cells. The transcriptome of these cells indicates that they belong to or are derived from the same lineage as the atrial multipotent c-kit^pos/CD45^neg/CD31^neg CSCs. Taken together the data presented here suggest that human myxomas could be the first-described CSC-related human heart disease.

Race-specific changes in endothelial inflammation and microRNA in response to an acute inflammatory stimulus

Both aberrant vascular reactivity to acute cardiovascular stress and epigenetic mechanisms such as microRNA (miR) may underlie the increased propensity for African Americans (AA) to develop cardiovascular disease. This study assessed racial differences in acute induced endothelial inflammation and related miRs. Cultured human umbilical vein endothelial cells (HUVECs) derived from AA and Caucasian Americans (CA) were exposed to influenza vaccine to determine changes in inflammatory markers, endothelial nitric oxide synthase (eNOS), and miR expression/release. Endothelial function [flow-mediated dilation (FMD)], circulating IL-6, and circulating miR were also measured in young, healthy AA and CA individuals before and after receiving the influenza vaccine. There were no significant racial differences in any parameters at baseline. The vaccine induced increases in IL-6 release (24%, P = 0.02) and ICAM-1 mRNA (40%, P = 0.03), as well as reduced eNOS mRNA (24%, P = 0.04) in AA HUVECs, but not in CA HUVECs (all P > 0.05). Intracellular levels of anti-inflammatory miR-221-3p and miR-222-3p increased specifically in CA HUVECs (72% and 53%, P = 0.04 and P = 0.06), whereas others did not change in either race. HUVEC secretion of several miRs decreased in both races, whereas the release of anti-inflammatory miR-150-5p was decreased only by AA cells (-30%, P = 0.03). In individuals of both races, circulating IL-6 increased approximately twofold 24 h after vaccination (both P < 0.01) and returned to baseline levels by 48 h, whereas FMD remained unchanged. Although macrovascular function was unaffected by acute inflammation in AA and CA individuals, AA endothelial cells exhibited increased susceptibility to acute inflammation and unique changes in related miR.NEW & NOTEWORTHY Used as an acute inflammatory stimulus, the influenza vaccine induced an inflammatory response and decreased eNOS gene expression in endothelial cells derived from African Americans, but not Caucasian Americans. Race-specific changes in intracellular expression and release of specific microRNAs also occurred and may contribute to an exaggerated inflammatory response in African Americans. In vivo, the vaccine caused similar systemic inflammation but had no effect on endothelial function or circulating microRNAs in individuals of either race.

Molecular Mechanisms Associated with ROS-Dependent Angiogenesis in Lower Extremity Artery Disease

Currently, atherosclerosis, which affects the vascular bed of all vital organs and tissues, is considered as a leading cause of death. Most commonly, atherosclerosis involves coronary and peripheral arteries, which results in acute (e.g., myocardial infarction, lower extremities ischemia) or chronic (persistent ischemia leading to severe heart failure) consequences. All of them have a marked unfavorable impact on the quality of life and are associated with increased mortality and morbidity in human populations. Lower extremity artery disease (LEAD, also defined as peripheral artery disease, PAD) refers to atherosclerotic occlusive disease of the lower extremities, where partial or complete obstruction of peripheral arteries is observed. Decreased perfusion can result in ischemic pain, non-healing wounds, and ischemic ulcers, and significantly reduce the quality of life. However, the progressive atherosclerotic changes cause stimulation of tissue response processes, like vessel wall remodeling and neovascularization. These mechanisms of adapting the vascular network to pathological conditions seem to play a key role in reducing the impact of the changes limiting the flow of blood. Neovascularization as a response to ischemia induces sprouting and expansion of the endothelium to repair and grow the vessels of the circulatory system. Neovascularization consists of three different biological processes: vasculogenesis, angiogenesis, and arteriogenesis. Both molecular and environmental factors that may affect the process of development and growth of blood vessels were analyzed. Particular attention was paid to the changes taking place during LEAD. It is important to consider the molecular mechanisms underpinning vessel growth. These mechanisms will also be examined in the context of diseases commonly affecting blood vessel function, or those treatable in part by manipulation of angiogenesis. Furthermore, it may be possible to induce the process of blood vessel development and growth to treat peripheral vascular disease and wound healing. Reactive oxygen species (ROS) play an important role in regulation of essential cellular signaling pathways such as cell differentiation, proliferation, migration and apoptosis. With regard to the repair processes taking place during diseases such as LEAD, prospective therapeutic methods have been described that could significantly improve the treatment of vessel diseases in the future. Summarizing, regenerative medicine holds the potential to transform the therapeutic methods in heart and vessel diseases treatment.

High expression of microRNA-126 relates to favorable prognosis for colon cancer patients

miR-126 has been identified both as a tumor suppressor and an oncogene in different types of cancer. The aim of this study was to investigate the prognostic impact of miR-126-expression in colon cancer patients. Tumor tissue from 452 patients operated for stage I–III colon cancer was retrospectively collected and tissue microarrays were constructed. miR-126 expression was evaluated by in situ hybridization and analyzed using digital pathology. To isolate the compartment specific contribution of miR-126, tumor and adjacent tumor stroma were considered separately. In univariate analyses, high expression of miR-126 in tumor and stroma was related to increased disease-specific survival (p < 0.001 and p = 0.005, respectively). In multivariate analyses, high miR-126 expression in tumor remained a significant independent predictor of improved disease-specific survival (HR = 0.42, CI 0.23–0.75, p = 0.004). Within different TNM-stages there was a tendency towards the same results, but with statistically significant results in stage II only (p = 0.007). High expression of miR-126 is an independent positive prognostic factor in stage I–III colon cancer. This finding may be used to identify patients in need of adjuvant chemotherapy.

Suppression of lncRNA HOTAIR alleviates RCC angiogenesis through regulating miR-126/EGFL7 axis

Renal cell carcinoma (RCC) has the highest mortality rate among urological cancers and tumor angiogenesis that plays a critical role in RCC progress. Epidermal growth factor-like domain multiple 7 (EGFL7) has been recently identified as a regulator in RCC tumor angiogenesis and progression. Long noncoding RNA (LncRNA) HOTAIR has been considered as a pro-oncogene in multiple cancers, but its precise mechanism of tumor angiogenesis has rarely been reported. MicroRNA-126 (miR-126) functions as a tumor suppressor in RCC. However, the underlying tumor angiogenesis mechanism of HOTAIR/miR-126 axis in RCC has not been studied. The proliferation, migration, angiogenesis, and expression of EGFL7 and related proteins in extracellular signal-regulated kinase (ERK)/activators of transcription 3 (STAT3) signal pathway were determined to examine the effect and mechanism of HOTAIR and miR-126 on RCC progress. The regulatory relationship of HOTAIR and miR-126, as well as miR-126 and EGFL7 were tested using dual-luciferase reporter assay. Aenograft RCC mice model was used to examine the effect of HOTAIR on RCC tumor growth and metastasis in vivo. HOTAIR knockdown and miR-126 overexpression suppressed the proliferation, migration, and angiogenesis of RCC cells. HOTAIR regulated EGFL7 expression by competitively binding to miR-126. Knockdown of HOTAIR significantly suppressed the RCC tumor progression and lung metastasis in vivo. These findings suggest that lncRNA HOTAIR regulate RCC angiogenesis through miR-126/EGFL7 axis and provide a new perspective on the molecular pathways of angiogenesis in RCC development, which might be potential therapeutic targets for RCC treatment.

Systems biology in cardiovascular disease: a multiomics approach

Omics techniques generate large, multidimensional data that are amenable to analysis by new informatics approaches alongside conventional statistical methods. Systems theories, including network analysis and machine learning, are well placed for analysing these data but must be applied with an understanding of the relevant biological and computational theories. Through applying these techniques to omics data, systems biology addresses the problems posed by the complex organization of biological processes. In this Review, we describe the techniques and sources of omics data, outline network theory, and highlight exemplars of novel approaches that combine gene regulatory and co-expression networks, proteomics, metabolomics, lipidomics and phenomics with informatics techniques to provide new insights into cardiovascular disease. The use of systems approaches will become necessary to integrate data from more than one omic technique. Although understanding the interactions between different omics data requires increasingly complex concepts and methods, we argue that hypothesis-driven investigations and independent validation must still accompany these novel systems biology approaches to realize their full potential.

The Vital Roles of Mesenchymal Stem Cells and the Derived Extracellular Vesicles in Promoting Angiogenesis After Acute Myocardial Infarction

Acute myocardial infarction (AMI) is an event of ischemic myocardial necrosis caused by acute coronary artery occlusion, which ultimately leads to a large loss of cardiomyocytes. The prerequisite of salvaging ischemic myocardium and improving cardiac function of patients is to provide adequate blood perfusion in the infarcted area. Apart from reperfusion therapy, it is also urgent and imperative to promote angiogenesis. Recently, growing evidence based on promising preclinical data indicates that mesenchymal stem cells (MSCs) can provide therapeutic effects on AMI by promoting angiogenesis. Extracellular vesicles (EVs), membrane-encapsulated vesicles with complex cargoes, including proteins, nucleic acids, and lipids, can be derived from MSCs and represent part of their functions, so EVs also possess the ability to promote angiogenesis. However, poor control of the survival and localization of MSCs hindered clinical transformation and made scientists start looking for new approaches based on MSCs. Identifying the role of MSCs and their derived EVs in promoting angiogenesis can provide a theoretical basis for improved MSC-based methods, and ultimately promote the clinical treatment of AMI. This review highlights potential proangiogenic mechanisms of transplanted MSCs and the derived EVs after AMI and summarizes the latest literature concerning the novel methods based on MSCs to maximize the angiogenesis capability.

Evaluation of VEGF-A in platelet and microRNA-126 in serum after coronary artery bypass grafting

Platelet functions are thought to contribute to clinical outcomes after heart surgery. This study was conducted to assess the pivotal roles of vascular endothelial growth factor-A (VEGF-A) and microRNA-126 (miR-126) during coronary artery bypass grafting (CABG). Whole blood was collected for platelet isolation from 67 patients who underwent CABG surgery between July 2013 and March 2014. VEGF-A and miR-126 levels in serum, plasma, and platelets were measured at various time points and compared with clinical characteristics. The platelet count was decreased at 3 days after CABG. This dynamic change in platelet count was larger after conventional coronary artery bypass (CCAB) than off-pump coronary artery bypass (OPCAB). VEGF-A in the same number of platelets (IP-VEGF-A) was increased at 3 days after CABG, followed by an increase of VEGF-A in serum (S-VEGF-A) at 7 days after surgery. The miR-126-3p level in serum (S-miR-126-3p) increased rapidly after CABG and then decreased below preoperative levels. The IP-VEGF-A level on day 7 after CABG in patients with peripheral artery disease (PAD), who suffered from endothelial dysfunction, was higher compared with patients without PAD. Conversely, S-miR-126-3p on day 7 after surgery was lower in patients with PAD than in patients without PAD. Low levels of S-miR-126-3p due to endothelial dysfunction may lead to high IP-VEGF-A, which is closely related to complications after CABG.

Atorvastatin improves the proliferation and migration of endothelial progenitor cells via the miR-221/VEGFA axis

The present study was aimed at investigating the detailed functions of atorvastatin, a lipid-lowering agent, in the pathogenesis of coronary slow flow (CSF), a clinical disease characterized by delayed angiographic coronary opacity without obstructive coronary disease. In the present study, we successfully identified isolated endothelial progenitor cells (EPCs) from the peripheral blood of patients with CSF. Their vascular endothelial growth factor-A (VEGFA) protein levels were determined using immunoblotting analyses. We determined cell viability using MTT assays, cell migration capacity using Transwell assays, and the angiogenic capacity using a tube formation assay. The target association between miR-221 and VEGFA was validated with a luciferase reporter assay. Atorvastatin treatment increased EPC VEGFA protein levels, proliferation, migration, and angiogenesis. miR-221 expression was down-regulated after atorvastatin treatment; miR-221 overexpression exerted an opposing effect to atorvastatin treatment on VEGFA protein, EPC proliferation, migration, and angiogenesis. The protective effects of atorvastatin treatment on VEGFA protein and EPCs could be significantly suppressed by miR-221 overexpression. miR-221 directly bound the VEGFA 3'UTR to inhibit its expression. In conclusion, atorvastatin improves the cell proliferation, migration, and angiogenesis of EPCs via the miR-221/VEGFA axis. Thus, atorvastatin could be a potent agent against CSF, pending further in vivo and clinical investigations.

Fasting-mediated metabolic and toxicity reprogramming impacts circulating microRNA levels in humans

It is well-established that long-term fasting improves metabolic health, enhances the total antioxidant capacity and increases well-being. MicroRNAs oversee energy homeostasis and metabolic processes and are widely used as circulating biomarkers to identify the metabolic state. This study investigated whether the expression levels of twenty-four metabolism-associated microRNAs are significantly altered following long-term fasting and if these changes correlate with biochemical and redox parameters in the plasma. Thirty-two participants with an average BMI of 28 kg/m² underwent a 10-day fasting period with a daily intake of 250 kcal under medical supervision. RT-qPCR on plasma small-RNA extracts revealed that the levels of seven microRNAs (miR-19b-3p, miR-22-3p, miR-122-5p, miR-126-3p, miR-142-3p, miR-143-3p, and miR-145-5p) were significantly altered following fasting. Importantly, the expression levels of these microRNAs have been consistently shown to change in the exact opposite direction in pathological states including obesity, diabetes, nonalcoholic steatohepatitis, and cardiovascular disease. Linear regression analyses revealed that among the microRNAs analyzed, anti-inflammatory miR-146-5p expression displayed most correlations with the levels of different biochemical and redox parameters. In silico analysis of fasting-associated microRNAs demonstrated that they target pathways that are highly enriched for intracellular signaling such mTOR, FoxO and autophagy, as well as extracellular matrix (ECM) interactions and cell-senescence. Overall, these data are consistent with a model in which long-term fasting engages homeostatic mechanisms associated with specific microRNAs to improve metabolic signaling regardless of health status.

The Anticancer Effects of Flavonoids through miRNAs Modulations in Triple-Negative Breast Cancer

Triple- negative breast cancer (TNBC) incidence rate has regularly risen over the last decades and is expected to increase in the future. Finding novel treatment options with minimum or no toxicity is of great importance in treating or preventing TNBC. Flavonoids are new attractive molecules that might fulfill this promising therapeutic option. Flavonoids have shown many biological activities, including antioxidant, anti-inflammatory, and anticancer effects. In addition to their anticancer effects by arresting the cell cycle, inducing apoptosis, and suppressing cancer cell proliferation, flavonoids can modulate non-coding microRNAs (miRNAs) function. Several preclinical and epidemiological studies indicate the possible therapeutic potential of these compounds. Flavonoids display a unique ability to change miRNAs' levels via different mechanisms, either by suppressing oncogenic miRNAs or activating oncosuppressor miRNAs or affecting transcriptional, epigenetic miRNA processing in TNBC. Flavonoids are not only involved in the regulation of miRNA-mediated cancer initiation, growth, proliferation, differentiation, invasion, metastasis, and epithelial-to-mesenchymal transition (EMT), but also control miRNAs-mediated biological processes that significantly impact TNBC, such as cell cycle, immune system, mitochondrial dysregulation, modulating signaling pathways, inflammation, and angiogenesis. In this review, we highlighted the role of miRNAs in TNBC cancer progression and the effect of flavonoids on miRNA regulation, emphasizing their anticipated role in the prevention and treatment of TNBC.

Maternal diabetes alters microRNA expression in fetal exosomes, human umbilical vein endothelial cells and placenta

BACKGROUND

Exposure to diabetes in utero influences future metabolic health of the offspring. MicroRNAs (miRNA) are small noncoding RNAs that may contribute mechanistically to the effects on offspring imparted by diabetes mellitus (DM) during pregnancy. We hypothesized that exposure to DM during pregnancy influences select miRNAs in fetal circulation, in human umbilical vein endothelial cells (HUVEC), and placenta.

METHODS

miRNA abundance was quantified using real-time PCR from RNA isolated from umbilical cord serum exosomes, HUVEC, and placenta exposed to diabetes or normoglycemia during pregnancy. The abundance of each of these miRNAs was determined by comparison to a known standard and the relative expression assessed using the 2-ΔΔCt method. Multivariable regression models examined the associations between exposure to diabetes during pregnancy and miRNA expression.

RESULTS

miR-126-3p was highly abundant in fetal circulation, HUVEC, and placenta. Diabetes exposure during pregnancy resulted in lower expression of miR-148a-3p and miR-29a-3p in the HUVEC. In the placenta, for miR-126-3p, there was a differential effect of DM by birth weight between DM versus control group, expression being lower at the lower birth weight, however not different at the higher birth weight.

CONCLUSION

Exposure to DM during pregnancy alters miRNA expression in the offspring in a tissue-specific manner.

IMPACT

miRNAs are differentially expressed in fetal tissues from offspring exposed to in utero diabetes mellitus compared to those who were not exposed. miRNA expression differs among tissue types (human umbilical vein endothelial cells, placenta and circulation exosomes) and response to diabetes exposure varies according to tissue of origin. miRNA expression is also affected by maternal and infant characteristics such as infant birth weight, infant sex, maternal age, and maternal BMI. miRNAs might be one of the potential mechanisms by which offspring's future metabolic status may be influenced by maternal diabetes mellitus.

Therapeutic Biomaterial Approaches to Alleviate Chronic Limb Threatening Ischemia

Chronic limb threatening ischemia (CLTI) is a severe condition defined by the blockage of arteries in the lower extremities that leads to the degeneration of blood vessels and is characterized by the formation of non-healing ulcers and necrosis. The gold standard therapies such as bypass and endovascular surgery aim at the removal of the blockage. These therapies are not suitable for the so-called "no option patients" which present multiple artery occlusions with a likelihood of significant limb amputation. Therefore, CLTI represents a significant clinical challenge, and the efforts of developing new treatments have been focused on stimulating angiogenesis in the ischemic muscle. The delivery of pro-angiogenic nucleic acid, protein, and stem cell-based interventions have limited efficacy due to their short survival. Engineered biomaterials have emerged as a promising method to improve the effectiveness of these latter strategies. Several synthetic and natural biomaterials are tested in different formulations aiming to incorporate nucleic acid, proteins, stem cells, macrophages, or endothelial cells in supportive matrices. In this review, an overview of the biomaterials used alone and in combination with growth factors, nucleic acid, and cells in preclinical models is provided and their potential to induce revascularization and regeneration for CLTI applications is discussed.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles in the Treatment of Diabetic Foot Ulcers: Application and Challenges

Diabetic foot ischemia and ulcer (DFU) persists as a serious diabetes mellitus complication in spite of increased understanding of the pathophysiology and the cellular and molecular responses. Contributing to this pessimistic situation is the lack of effective treatments that are slow to heal the deep chronic wounds and microvascular obstruction. Mesenchymal stromal cells (MSCs) have been tested as a promising cell-based therapy for diabetes in vitro and in vivo, which is able to accelerate wound closure with increased epithelialization, granulation tissue formation and angiogenesis by differentiation into skin cells and paracrine pathways to repair injured cells. The secretomes of MSCs, including cytokines, growth factors, chemokines, and extracellular vesicles containing mRNA, proteins and microRNAs, have immunomodulatory and regenerative effects. This review will shed new light on the therapeutic potential of MSC-derived extracellular vesicles (MSC-EVs) for the treatment of diabetes-induced lower limb ischemia and ulcers. The identification of underlying mechanisms for MSC-EVs regulation on impaired diabetic wound healing might provide a new direction for MSC-centered treatment for diabetic lower limb ischemia and ulcers. Immunomodulatory and angiogenic effects of MSC-derived extracellular vesicles on diabetic foot ulcer.

Lead (Pb) exposure is associated with changes in the expression levels of circulating miRNAS (miR-155, miR-126) in Mexican women

The environmental contamination with lead (Pb) is considered a critical issue worldwide. Therefore, this study aimed to evaluate the expression levels of circulating miRNAs (miR-155, miR-126, and miR-145) in Mexican women exposed to Pb. Blood lead levels (BLL) were assessed in enrolled women (n = 190) using an atomic absorption method. Also, serum miRNAs expression levels were quantified through a real-time PCR assay. A mean BLL of 10.5 ± 4.50 μg/dL was detected. Overexpression of miR-155 was detected in highly exposed women. Besides, a significant simple positive relationship (p < 0.05) was found between BLL and serum miR-155 expression levels. Additionally, a significant inverse correlation (p < 0.05) was determined between BLL and serum miR-126 expression levels, as downregulation of miR-126 expression levels was observed in highly exposed women. The findings in this study are the concern, as epigenetic changes detected may represent a connection between health illnesses and Pb exposure.

Non-coding RNAs related to angiogenesis in gynecological cancer

Gynecological cancer affects the female reproductive system, including ovarian, uterine, endometrial, cervical, vulvar, and vaginal tumors. Non-coding RNAs (ncRNAs), and in particular microRNAs, function as regulatory molecules, which can control gene expression in a post-transcriptional manner. Normal physiological processes like cellular proliferation, differentiation, and apoptosis, and pathological processes such as oncogenesis and metastasis are regulated by microRNAs. Numerous reports have shown a direct role of microRNAs in the modulation of angiogenesis in gynecological cancer, via targeting pro-angiogenic factors and signaling pathways. Understanding the molecular mechanism involved in the regulation of angiogenesis by microRNAs may lead to new treatment options. Recently the regulatory role of some long non-coding RNAs in gynecological cancer has also been explored, but the information on this function is more limited. The aim of this article is to explore the pathways responsible for angiogenesis, and to what extent ncRNAs may be employed as biomarkers or therapeutic targets in gynecological cancer.

High Glucose Treatment Limits Drosha Protein Expression and Alters AngiomiR Maturation in Microvascular Primary Endothelial Cells via an Mdm2-dependent Mechanism

Diabetes promotes an angiostatic phenotype in the microvascular endothelium of skeletal muscle and skin. Angiogenesis-related microRNAs (angiomiRs) regulate angiogenesis through the translational repression of pro- and anti-angiogenic genes. The maturation of micro-RNA (miRs), including angiomiRs, requires the action of DROSHA and DICER proteins. While hyperglycemia modifies the expression of angiomiRs, it is unknown whether high glucose conditions alter the maturation process of angiomiRs in dermal and skeletal muscle microvascular endothelial cells (MECs). Compared to 5 mM of glucose, high glucose condition (30 mM, 6-24 h) decreased DROSHA protein expression, without changing DROSHA mRNA, DICER mRNA, or DICER protein in primary dermal MECs. Despite DROSHA decreasing, high glucose enhanced the maturation and expression of one angiomiR, miR-15a, and downregulated an miR-15a target: Vascular Endothelial Growth Factor-A (VEGF-A). The high glucose condition increased Murine Double Minute-2 (MDM2) expression and MDM2-binding to DROSHA. Inhibition of MDM2 prevented the effects evoked by high glucose on DROSHA protein and miR-15a maturation in dermal MECs. In db/db mice, blood glucose was negatively correlated with the expression of skeletal muscle DROSHA protein, and high glucose decreased DROSHA protein in skeletal muscle MECs. Altogether, our results suggest that high glucose reduces DROSHA protein and enhances the maturation of the angiostatic miR-15a through a mechanism that requires MDM2 activity.

Regulation of endothelial cell differentiation in embryonic vascular development and its therapeutic potential in cardiovascular diseases

During vertebrate development, the cardiovascular system begins operating earlier than any other organ in the embryo. Endothelial cell (EC) forms the inner lining of blood vessels, and its extensive proliferation and migration are requisite for vasculogenesis and angiogenesis. Many aspects of cellular biology are involved in vasculogenesis and angiogenesis, including the tip versus stalk cell specification. Recently, epigenetics has attracted growing attention in regulating embryonic vascular development and controlling EC differentiation. Some proteins that regulate chromatin structure have been shown to be directly implicated in human cardiovascular diseases. Additionally, the roles of important EC signaling such as vascular endothelial growth factor and its receptors, angiopoietin-1 and tyrosine kinase containing immunoglobulin and epidermal growth factor homology domain-2, and transforming growth factor-β in EC differentiation during embryonic vasculature development are briefly discussed in this review. Recently, the transplantation of human induced pluripotent stem cell (iPSC)-ECs are promising approaches for the treatment of ischemic cardiovascular disease including myocardial infarction. Patient-specific iPSC-derived EC is a potential new target to study differences in gene expression or response to drugs. However, clinical application of the iPSC-ECs in regenerative medicine is often limited by the challenges of maintaining cell viability and function. Therefore, novel insights into the molecular mechanisms underlying EC differentiation might provide a better understanding of embryonic vascular development and bring out more effective EC-based therapeutic strategies for cardiovascular diseases.

Oncolytic adenovirus: A tool for reversing the tumor microenvironment and promoting cancer treatment (Review)

Immunogene therapy can enhance the antitumor immune effect by introducing genes encoding co‑stimulation molecules, cytokines, chemokines and tumor‑associated antigens into treatment cells or human cells through genetic engineering techniques. Oncolytic viruses can specifically target tumor cells and replicate indefinitely until they kill tumor cells. If combined with immunogene therapy, oncolytic viruses can play a more powerful antitumor role. The high pressure, hypoxia and acidity in the tumor microenvironment (TME) provide suitable conditions for tumor cells to survive. To maximize the potency of oncolytic viruses, various methods are being developed to promote the reversal of the TME, thereby maximizing transmission of replication and immunogenicity. The aim of the present review was to discuss the basic mechanisms underlying the effects of oncolytic adenoviruses on the TME, and suggest how to combine the modification of the adenovirus with the TME to further combat malignant tumors.

Two novel microRNAs and their association with absolute blood pressure parameters in an urban South African community

MicroRNAs are important in development of disease, and description of novel microRNAs adds to the pool of microRNAs that can be targeted for diagnostic and therapeutic purposes in disease. Herein, we aimed to describe novel microRNAs in a normotensive and hypertensive African population and relate their expression to blood pressure parameters and hypertension status. Previous work using next-generation sequencing showed differential expression of two novel microRNAs in the blood of normotensives and hypertensives. Herein, we have investigated these novel microRNAs by quantitative reverse transcription polymerase chain reaction in a cohort of 881 participants in this study. The relationship between the novel microRNAs and systolic and diastolic blood pressure as well as mean arterial pressure was also investigated. Age and sex-adjusted Spearman’s correlations were used to assess the relationship between microRNAs and cardiovascular risk profile variables whilst multivariable logistic regression models were used to assess the association of microRNAs with screen-detected and known hypertension. The novel microRNAs (miR-novel-chr1_36178 and miR-novel-chr15_18383) were significantly dysregulated by hypertension status. The expression of miR-novel-chr1_36178 differed according to sex, correlated with mean arterial pressure and systolic and diastolic blood pressure at higher levels of expression and was associated with screen-detected hypertension. The association of miR-novel-chr1_36178 expression with mean arterial pressure and systolic and diastolic blood pressure, as well as its dysregulation according to hypertension status suggests its possible utility as a biomarker target for hypertension diagnosis and/or therapeutics. Furthermore, its association with screen detected hypertension and dose-response relationship with blood pressure suggests it may be used to identify and monitor individuals at risk of hypertension.

MicroRNAs as Predictive Biomarkers of Resistance to Targeted Therapies in Gastrointestinal Tumors

The advent of precision therapies against specific gene alterations characterizing different neoplasms is revolutionizing the oncology field, opening novel treatment scenarios. However, the onset of resistance mechanisms put in place by the tumor is increasingly emerging, making the use of these drugs ineffective over time. Therefore, the search for indicators that can monitor the development of resistance mechanisms and above all ways to overcome it, is increasingly important. In this scenario, microRNAs are ideal candidate biomarkers, being crucial post-transcriptional regulators of gene expression with a well-known role in mediating mechanisms of drug resistance. Moreover, as microRNAs are stable molecules, easily detectable in tissues and biofluids, they are the ideal candidate biomarker to identify patients with primary resistance to a specific targeted therapy and those who have developed acquired resistance. The aim of this review is to summarize the major studies that have investigated the role of microRNAs as mediators of resistance to targeted therapies currently in use in gastro-intestinal neoplasms, namely anti-EGFR, anti-HER2 and anti-VEGF antibodies, small-molecule tyrosine kinase inhibitors and immune checkpoint inhibitors. For every microRNA and microRNA signature analyzed, the putative mechanisms underlying drug resistance were outlined and the potential to be translated in clinical practice was evaluated.

Extracellular vesicle microRNA in early versus late pregnancy with birth outcomes in the MADRES study

Circulating miRNA may contribute to the development of adverse birth outcomes. However, few studies have investigated extracellular vesicle (EV) miRNA, which play important roles in intercellular communication, or compared miRNA at multiple time points in pregnancy. In the current study, 800 miRNA were profiled for EVs from maternal plasma collected in early (median: 12.5 weeks) and late (median: 31.8 weeks) pregnancy from 156 participants in the MADRES Study, a health disparity pregnancy cohort. Associations between miRNA and birth weight, birth weight for gestational age (GA), and GA at birth were examined using covariate-adjusted robust linear regression. Differences by infant sex and maternal BMI were also investigated. Late pregnancy measures of 13 miRNA were associated with GA at birth (P_FDR<0.050). Negative associations were observed for eight miRNA (miR-4454+ miR-7975, miR-4516, let-7b-5p, miR-126-3p, miR-29b-3p, miR-15a-5p, miR-15b-5p, miR-19b-3p) and positive associations for five miRNA (miR-212-3p, miR-584-5p, miR-608, miR-210-3p, miR-188-5p). Predicted target genes were enriched (P_FDR<0.050) in pathways involved in organogenesis and placental development. An additional miRNA (miR-107), measured in late pregnancy, was positively associated with GA at birth in infants born to obese women (P_FDR for BMI interaction = 0.011). In primary analyses, the associations between early pregnancy miRNA and birth outcomes were not statistically significant (P_FDR≥0.05). However, sex-specific associations were observed for early pregnancy measures of 37 miRNA and GA at birth (P_FDR for interactions<0.050). None of the miRNA were associated with fetal growth measures (P_FDR≥0.050). Our findings suggest that EV miRNA in both early and late pregnancy may influence gestational duration.

Molecular mechanisms underlying fructose-induced cardiovascular disease: exercise, metabolic pathways and microRNAs

NEW FINDINGS

What is the central question of this study? What are the mechanisms underlying the cardiac protective effect of aerobic training in the progression of a high fructose-induced cardiometabolic disease in Wistar rats? What is the main finding and its importance? At the onset of cardiovascular disease, aerobic training activates the p-p70S6K, ERK and IRβ-PI3K-AKT pathways, without changing the miR-126 and miR-195 levels, thereby providing evidence that aerobic training modulates the insulin signalling pathway. These data contribute to the understanding of the molecular cardiac changes that are associated with physiological left ventricular hypertrophy during the development of a cardiovascular disease.

ABSTRACT

During the onset of cardiovascular disease (CVD), disturbances in myocardial vascularization, cell proliferation and protein expression are observed. Aerobic training prevents CVD, but the underlying mechanisms behind left ventricle (LV) hypertrophy are not fully elucidated. The aim of this study was to investigate the mechanisms by which aerobic training protects the heart from LV hypertrophy during the onset of fructose-induced cardiometabolic disease. Male Wistar rats were allocated to four groups (n = 8/group): control sedentary (C), control training (CT), fructose sedentary (F) and fructose training (FT). The C and CT groups received drinking water, and the F and FT groups received d-fructose (10% in water). After 2 weeks, the CT and FT rats were assigned to a treadmill training protocol at moderate intensity for 8 weeks (60 min/day, 4 days/week). After 10 weeks, LV morphological remodelling, cardiomyocyte apoptosis, microRNAs and the insulin signalling pathway were investigated. The F group had systemic cardiometabolic alterations, which were normalised by aerobic training. The LV weight increased in the FT group, myocardium vascularisation decreased in the F group, and the cardiomyocyte area increased in the CT, F and FT groups. Regarding protein expression, total insulin receptor β-subunit (IRβ) decreased in the F group; phospho (p)-IRβ and phosphoinositide 3-kinase (PI3K) increased in the FT group; total-AKT and p-AKT increased in all of the groups; p-p70S6 kinase (p70S6K) protein was higher in the CT group; and p-extracellular signal-regulated kinase (ERK) increased in the CT and FT groups. MiR-126, miR-195 and cardiomyocyte apoptosis did not differ among the groups. Aerobic training activates p-p70S6K and p-ERK, and during the onset of a CVD, it can activate the IRβ-PI3K-AKT pathway.

The protective role of MiR-206 in regulating cardiomyocytes apoptosis induced by ischemic injury by targeting PTP1B

MicroRNAs play essential roles in the regulation and pathophysiology of acute myocardial infarction (AMI). The purpose of the present study was to assess the expression signature of miR-206 in rat heart with AMI and the corresponding molecular mechanism. The expression of miR-206 significantly decreased in the infarcted myocardial areas and in hypoxia-induced cardiomyocytes, compared with that in the noninfarcted areas. Overexpression of miR-206 decreased cardiomyocytes apoptosis and the down-regulation of miR-206 increased cardiomyocytes apoptosis in vitro. In addition, overexpression of miR-206 in rat heart in vivo remarkably reduced myocardial infarct size and cardiomyocytes apoptosis. We identified that miR-206 had a protective effect on cardiomyocytes apoptosis with the association of its target protein tyrosine phosphatase 1B (PTP1B). Gain-of-function of miR-206 inhibited PTP1B expression and loss-of-function of miR-206 up-regulated PTP1B expression. Furthermore, overexpression of PTP1B significantly increased cardiomyocytes apoptosis. These results together suggest the protective effect of miR-206 against cardiomyocytes apoptosis induced by AMI by targeting PTP1B.

MicroRNA-126 inhibits pathological retinal neovascularization via suppressing vascular endothelial growth factor expression in a rat model of retinopathy of prematurity

Vascular endothelial growth factor (VEGF) is the principal growth factor responsible for the retinal neovascularization in the pathogenesis of retinopathy of prematurity (ROP). Current therapies for ROP include laser ablation and intravitreal anti-VEGF injection. However, these treatments either destroy the peripheral retina or associate with problems of persistent peripheral avascular retina or later recurrence of ROP. In the present study we investigated a new therapeutic approach by exploring the potential role of a specific microRNA, miR-126, in regulating VEGFA expression and retinal neovascularization in a rat oxygen-induced retinopathy (OIR) model. We demonstrated that miR-126 mimic and plasmid effectively suppresses VEGFA mRNA expression in both human and rat retinal pigment epithelium cell lines, quantified with qRT-PCR. Animal experiments on rat OIR model revealed that intravitreal injection of miR-126 plasmid efficiently downregulated VEGFA expression in the intraocular fluid and retinal tissues measured by ELISA, and significantly suppressed retinal neovascularization, which was confirmed by calculating sizes of neovascularization areas on fluorescence microscopic images of flat mounted retina stained with Alexa Fluor 594-conjugated isolectin B4 to visualize blood vessels. Together, these results showed that intravitreal injection of miR-126 plasmid could inhibit retinal neovascularization by down-regulating VEGFA expression, suggesting a potential therapeutic effect for ROP.

Trimetazidine Increases Plasma MicroRNA-24 and MicroRNA-126 Levels and Improves Dyslipidemia, Inflammation and Hypotension in Diabetic Rats

Trimetazidine (TMZ) improves endothelial dysfunction. However, its beneficial effect on endothelial miRNAs is unexplored in diabetes. The aim of the present study was to evaluate the effects of TMZ on plasma miRNA-24 and miRNA-126, dyslipidemia, inflammation, and blood pressure in the diabetic rats. Adult male Sprague-Dawley rats were randomly assigned into four groups (250 ± 20 g, n = 8): a control (C), an untreated diabetic (D), a diabetic group administrated with TMZ at 10 mg/kg (T10), and a diabetic group administrated with TMZ at 30 mg/kg (T30) for eight weeks. Diabetes was induced by injection of alloxan (120 mg/kg). The plasma levels of miR-24, miR-126, lipid profile, malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), blood glucose, body weight and systolic blood pressure were measured. The diabetic rats showed decreased plasma miR-24, HDL-c (P < 0.05), miR-126 (P < 0.01), body weight changes percent, body weight, and systolic blood pressure (P < 0.001) and increased triglycerides (TG), VLDL-c (P < 0.05), TNF-α, total cholesterol (TC) (P < 0.01) glucose, MDA and IL-6 (P < 0.001). Interestingly, all these changes were significantly improved by TMZ treatment. Our findings propose that TMZ has protective effects on decreased plasma miR-24 and miR-126 levels, inflammation, dyslipidemia and hypotension, and it may participate in endothelial dysfunction and atherosclerosis.

Long non-coding RNA NEAT1 regulates endothelial functions in subclinical hypothyroidism through miR-126/TRAF7 pathway

Subclinical hypothyroidism (SCH) is associated with increased risks of endothelial dysfunction and atherosclerosis, but the mechanisms remain unclear. In our previous study, microRNA-126-3p was downregulated in SCH, but the role and regulatory mechanism of miR-126 in SCH has not been investigated. A SCH mouse model was established by feeding mice methimazole. Both primary endothelial cells (ECs) and HUVECs were cultured. The expression levels of key molecules were detected via quantitative RT-PCR, western blotting, and immunofluorescence. Wire myography was used to analyze the changes in vascular tones. A dual-luciferase assay was used to investigate the relationship between lncRNAs, microRNAs and target genes. In detail, it was shown that the expression levels of miR-126-3p were significantly decreased in both the SCH vasculature and HUVECs. MiR-126 supplementation suppressed HUVEC apoptosis and improved vascular function. Moreover, miR-126 could bind to the 3'-untranslated region of TRAF7, thus, regulating the C-FLIP pathway and endothelial apoptosis. Furthermore, lncRNA NEAT1 was upregulated upon TSH treatment and could function as a ceRNA and bind to miR-126, thus, modulating its expression level and vascular function. Finally, the NEAT1/miR-126/TRAF7 axis functions in response to TSH and regulates endothelial functions in SCH in vitro and in vivo. In conclusion, dysregulation of the NEAT1/miR-126/TRAF7 axis is responsible for impaired endothelial functions in SCH. Targeting this axis might become a promising treatment strategy or improving endothelial functions in SCH.

miR-130a activates the VEGFR2/STAT3/HIF1α axis to potentiate the vasoregenerative capacity of endothelial colony-forming cells in hypoxia

Hypoxia modulates reparative angiogenesis, which is a tightly regulated pathophysiological process. MicroRNAs (miRNAs) are important regulators of gene expression in hypoxia and angiogenesis. However, we do not yet have a clear understanding of how hypoxia-induced miRNAs fine-tune vasoreparative processes. Here, we identify miR-130a as a mediator of the hypoxic response in human primary endothelial colony-forming cells (ECFCs), a well-characterized subtype of endothelial progenitors. Under hypoxic conditions of 1% O2, miR-130a gain-of-function enhances ECFC pro-angiogenic capacity in vitro and potentiates their vasoreparative properties in vivo. Mechanistically, miR-130a orchestrates upregulation of VEGFR2, activation of STAT3, and accumulation of HIF1α via translational inhibition of Ddx6. These findings unveil a new role for miR-130a in hypoxia, whereby it activates the VEGFR2/STAT3/HIF1α axis to enhance the vasoregenerative capacity of ECFCs.

Regulation of miRNAs by Natural Antioxidants in Cardiovascular Diseases: Focus on SIRT1 and eNOS

Cardiovascular diseases (CVDs) are the most common cause of morbidity and mortality worldwide. The potential benefits of natural antioxidants derived from supplemental nutrients against CVDs are well known. Remarkably, natural antioxidants exert cardioprotective effects by reducing oxidative stress, increasing vasodilation, and normalizing endothelial dysfunction. Recently, considerable evidence has highlighted an important role played by the synergistic interaction between endothelial nitric oxide synthase (eNOS) and sirtuin 1 (SIRT1) in the maintenance of endothelial function. To provide a new perspective on the role of natural antioxidants against CVDs, we focused on microRNAs (miRNAs), which are important posttranscriptional modulators in human diseases. Several miRNAs are regulated via the consumption of natural antioxidants and are related to the regulation of oxidative stress by targeting eNOS and/or SIRT1. In this review, we have discussed the specific molecular regulation of eNOS/SIRT1-related endothelial dysfunction and its contribution to CVD pathologies; furthermore, we selected nine different miRNAs that target the expression of eNOS and SIRT1 in CVDs. Additionally, we have summarized the alteration of miRNA expression and regulation of activities of miRNA through natural antioxidant consumption.

Serum miRNA Signature in Rheumatoid Arthritis and "At-Risk Individuals"

Background

MicroRNAs (miRNAs) are small non-coding RNAs which have been implicated as potential biomarkers or therapeutic targets in autoimmune diseases. This study examines circulatory miRNAs in RA patients and further investigates if a serum miRNA signature precedes clinical manifestations of disease in arthralgia or “at-risk individuals”.

Methods

Serum was collected from HC subjects (N = 20), RA patients (N = 50), and arthralgia subjects (N = 10), in addition to a subgroup of the RA patients post-methotrexate (MTX) (N = 18). The FirePlex miRNA Immunology-V2 panel was selected for multiplex analysis of 68 miRNAs in each sample. DNA intelligent analysis (DIANA)-mirPath and Ingenuity Pathway Analysis (IPA) software were used to predict pathways targeted by the dysregulated miRNAs.

Results

8 miRNA (miR-126-3p, let-7d-5p, miR-431-3p, miR-221-3p, miR-24-3p, miR-130a-3p, miR-339-5p, let-7i-5p) were significantly elevated in RA serum compared to HC (all p < 0.01) and 1 miRNA (miR-17-5p) was significantly lower in RA (p < 0.01). High specificity and sensitivity were determined by receiver operating characteristic (ROC) curve analysis. Both miR-339-5p and let-7i-5p were significantly reduced post-MTX (both p < 0.01). MiR-126-3p, let-7d-5p, miR-431-3p, miR-221-3p, miR-24-3p, miR-130a-3p were also significantly elevated in subjects “at risk” of developing RA (all p < 0.05) compared to HC. IPA analysis of this miRNA signature identified downstream targets including key transcription factors NF-κB, STAT-1, STAT-3, cytokines IL-1β, TNF-α, and matrix-metalloproteases all importantly associated with RA pathogenesis.

Conclusion

This study identified six miRNAs that are altered in both RA and “at-risk individuals,” which potentially regulate key downstream pathways involved in regulating inflammation. These may have potential as predictive signature for disease onset and early progression.

Inhibition of miR-200b Promotes Angiogenesis in Endothelial Cells by Activating The Notch Pathway

Objective

Patients with diabetes mellitus frequently have chronic wounds or diabetic ulcers as a result of impaired wound healing, which may lead to limb amputation. Human umbilical vein endothelial cell (HUVEC) dysfunction also delays wound healing. Here, we investigated the mechanism of miR-200b in HUVECs under high glucose conditions and the potential of miR-200b as a therapeutic target.

Materials and Methods

In this experimental study, HUVECs were cultured with 5 or 30 mM glucose for 48 hours. Cell proliferation was evaluated by CCK-8 assays. Cell mobility was tested by wound healing and Transwell assays. Angiogenesis was analyzed in vitro Matrigel tube formation assays. Luciferase reporter assays were used to test the binding of miR-200b with Notch1.

Results

miR-200b expression was induced by high glucose treatment of HUVECs (P<0.01), and it significantly repressed cell proliferation, migration, and tube formation (P<0.05). Notch1 was directly targeted and repressed by miR-200b at both the mRNA and protein levels. Inhibition of miR-200b restored Notch1 expression (P<0.05) and reactivated the Notch pathway. The effects of miR-200b inhibition in HUVECs could be reversed by treatment with a Notch pathway inhibitor (P<0.05), indicating that the miR-200b/Notch axis modulates the proliferation, migration, and tube formation ability of HUVECs.

Conclusion

Inhibition of miR-200b activated the angiogenic ability of endothelial cells and promoted wound healing through reactivation of the Notch pathway in vitro. miR-200b could be a promising therapeutic target for treating HUVEC dysfunction.

Endothelium-dependent remote signaling in ischemia and reperfusion: Alterations in the cardiometabolic continuum

Intact endothelial function plays a fundamental role for the maintenance of cardiovascular (CV) health. The endothelium is also involved in remote signaling pathway-mediated protection against ischemia/reperfusion (I/R) injury. However, the transfer of these protective signals into clinical practice has been hampered by the complex metabolic alterations frequently observed in the cardiometabolic continuum, which affect redox balance and inflammatory pathways. Despite recent advances in determining the distinct roles of hyperglycemia, insulin resistance (InR), hyperinsulinemia, and ultimately diabetes mellitus (DM), which define the cardiometabolic continuum, our understanding of how these conditions modulate endothelial signaling remains challenging. It is widely accepted that endothelial cells (ECs) undergo functional changes within the cardiometabolic continuum. Beyond vascular tone and platelet-endothelium interaction, endothelial dysfunction may have profound negative effects on outcome during I/R. In this review, we summarize the current knowledge of the influence of hyperglycemia, InR, hyperinsulinemia, and DM on endothelial function and redox balance, their influence on remote protective signaling pathways, and their impact on potential therapeutic strategies to optimize protective heterocellular signaling.

Mucosal microRNAs relate to age and severity of disease in ulcerative colitis

Despite significant evidence that the expression of several microRNAs (miRNAs) impacts disease activity in patients with ulcerative colitis (UC), it remains unknown if the more severe disease phenotype seen in pediatric onset UC can be explained by an altered miRNA expression. In this study, we assessed the relationship between miRNA expression, age, and disease severity in pediatric and adult patients with UC. Using RT-qPCR, we analyzed the expression of miR-21, miR-31, miR-126, miR-142 and miR-155 in paraffin embedded rectum biopsies from 30 pediatric and 30 adult-onset UC patients. We found that lesions from adult patients had significantly higher expression levels of miR-21 compared to pediatric patients and that the expression levels of miR-31 (all patients) and miR-155 (pediatric patients only) correlated inversely with histological assessed disease severity. Using in situ hybridization followed by image analysis, the expression level estimates of miR-21 and miR-126 correlated with histological assessed disease severity. In conclusion, we found that the expression of miRNAs depends on the age of the patient and/or the severity of the disease, suggesting that miRNAs may contribute to the regulation of inflammation in UC and could be useful biomarkers in the surveillance of disease severity.

Low-activity programming of the PDGFRβ/FAK pathway mediates H-type vessel dysplasia and high susceptibility to osteoporosis in female offspring rats after prenatal dexamethasone exposure

Dexamethasone is a common synthetic glucocorticoid drug that can promote foetal lung maturity. An increasing number of studies have shown that prenatal dexamethasone exposure (PDE) can cause a variety of short-term and long-term hazards to offspring, including bone development toxicity. H-type vessels are a newly discovered subtype of blood vessels associated with promoted bone formation and maintenance of bone mass. In this study, we aimed to explore whether H-type blood vessels are involved in PDE-induced long bone development toxicity in offspring and its mechanism. In vivo, we injected dexamethasone (0.2 mg/kg.d) subcutaneously at gestational days 9-20 and observed the H-type vessel abundance and bone mass at different time points in the offspring rats. In vitro, we investigated the effect of dexamethasone (0, 20, 100, and 500 nM) on the tube formation function of rat bone marrow-derived endothelial progenitor cells (EPCs) and explored its mechanism. Our results showed that the adult PDE female offspring rats were susceptible to osteoporosis. In addition, PDE inhibited bone mass, H-type vessel formation and the expression of bone platelet-derived growth factor receptor β (PDGFRβ)/focal adhesion kinase (FAK) pathway-related genes in antenatal and postnatal female offspring. Moreover, PDE promoted the expression of bone glucocorticoid receptor (GR), CCAAT and enhancer binding protein α (C/EBPα) and miR-34c in female foetuses. Dexamethasone suppressed the tube formation of rat bone marrow-derived EPCs and the activity of the PDGFRβ/FAK pathway, which was mediated by GR/C/EBPα/miR-34c signalling activation. In summary, PDE can cause H-type vessel dysplasia and high susceptibility to osteoporosis in female offspring, and its mechanism is related to the low-activity programming of the PDGFRβ/FAK pathway induced by GR/C/EBPα/miR-34c signalling activation. This study enhances the understanding of the molecular mechanism of dexamethasone-induced bone development toxicity and provides new insights for exploring the early intervention and therapeutic targets of foetal-derived osteoporosis.

The vasculature: a therapeutic target in heart failure?

It is well established that the vasculature plays a crucial role in maintaining oxygen and nutrients supply to the heart. Increasing evidence further suggest that the microcirculation has additional roles in supporting a healthy microenvironment. Heart failure is well known to be associated with changes and functional impairment of the microvasculature. The specific ablation of protective signals in endothelial cells in experimental models is sufficient to induce heart failure. Therefore, restoring a healthy endothelium and microcirculation may be a valuable therapeutic strategy to treat heart failure. The present review article will summarize the current understanding of the vascular contribution to heart failure with reduced or preserved ejection fraction. Novel therapeutic approaches including next generation pro-angiogenic therapies and non-coding RNA therapeutics, as well as the targeting of metabolites or metabolic signaling, vascular inflammation and senescence will be discussed.

A Comprehensive miRNome Analysis of Macrophages Isolated from db/db Mice and Selected miRNAs Involved in Metabolic Syndrome-Associated Cardiac Remodeling

Cardiac macrophages are known from various activities, therefore we presume that microRNAs (miRNAs) produced or released by macrophages in cardiac tissue have impact on myocardial remodeling in individuals with metabolic syndrome (MetS). We aim to assess the cardiac macrophage miRNA profile by selecting those miRNA molecules that potentially exhibit regulatory functions in MetS-related cardiac remodeling. Cardiac tissue macrophages from control and db/db mice (an animal model of MetS) were counted and sorted with flow cytometry, which yielded two populations: CD45+CD11b+CD64+Ly6Chi and CD45+CD11b+CD64+Ly6Clow. Total RNA was then isolated, and miRNA expression profiles were evaluated with Next Generation Sequencing. We successfully sequenced 1400 miRNAs in both macrophage populations: CD45+CD11b+CD64+Ly6Chi and CD45+CD11b+CD64+Ly6Clow. Among the 1400 miRNAs, about 150 showed different expression levels in control and db/db mice and between these two subpopulations. At least 15 miRNAs are possibly associated with MetS pathology in cardiac tissue due to direct or indirect regulation of the expression of miRNAs for proteins involved in angiogenesis, fibrosis, or inflammation. In this paper, for the first time we describe the miRNA transcription profile in two distinct macrophage populations in MetS-affected cardiac tissue. Although the results are preliminary, the presented data provide a foundation for further studies on intercellular cross-talk/molecular mechanism(s) involved in the regulation of MetS-related cardiac remodeling.

Cell type-specific microRNA therapies for myocardial infarction

Current interventions fail to recover injured myocardium after infarction and prompt the need for development of cardioprotective strategies. Of increasing interest is the therapeutic use of microRNAs to control gene expression through specific targeting of mRNAs. In this Review, we discuss current microRNA-based therapeutic strategies, describing the outcomes and limitations of key microRNAs with a focus on target cell types and molecular pathways. Last, we offer a perspective on the outlook of microRNA therapies for myocardial infarction, highlighting the outstanding challenges and emerging strategies.

Can Be miR-126-3p a Biomarker of Premature Aging? An Ex Vivo and In Vitro Study in Fabry Disease

Fabry disease (FD) is a lysosomal storage disorder (LSD) characterized by lysosomal accumulation of glycosphingolipids in a wide variety of cytotypes, including endothelial cells (ECs). FD patients experience a significantly reduced life expectancy compared to the general population; therefore, the association with a premature aging process would be plausible. To assess this hypothesis, miR-126-3p, a senescence-associated microRNA (SA-miRNAs), was considered as an aging biomarker. The levels of miR-126-3p contained in small extracellular vesicles (sEVs), with about 130 nm of diameter, were measured in FD patients and healthy subjects divided into age classes, in vitro, in human umbilical vein endothelial cells (HUVECs) "young" and undergoing replicative senescence, through a quantitative polymerase chain reaction (qPCR) approach. We confirmed that, in vivo, circulating miR-126 levels physiologically increase with age. In vitro, miR-126 augments in HUVECs underwent replicative senescence. We observed that FD patients are characterized by higher miR-126-3p levels in sEVs, compared to age-matched healthy subjects. We also explored, in vitro, the effect on ECs of glycosphingolipids that are typically accumulated in FD patients. We observed that FD storage substances induced in HUVECs premature senescence and increased of miR-126-3p levels. This study reinforces the hypothesis that FD may aggravate the normal aging process.

Systematic review of microRNA biomarkers in acute coronary syndrome and stable coronary artery disease

The aim of this systematic review was to assess dysregulated miRNA biomarkers in coronary artery disease (CAD). Dysregulated microRNA (miRNAs) have been shown to be linked to cardiovascular pathologies including CAD and may have utility as diagnostic and prognostic biomarkers. We compared miRNAs identified in acute coronary syndrome (ACS) compared with stable CAD and control populations. We conducted a systematic search of controlled vocabulary and free text terms related to ACS, stable CAD and miRNA in Biosis Previews (OvidSP), The Cochrane Library (Wiley), Embase (OvidSP), Global Health (OvidSP), Medline (PubMed and OvidSP), Web of Science (Clarivate Analytics), and ClinicalTrials.gov which yielded 7370 articles. Of these, 140 original articles were appropriate for data extraction. The most frequently reported miRNAs in any CAD (miR-1, miR-133a, miR-208a/b, and miR-499) are expressed abundantly in the heart and play crucial roles in cardiac physiology. In studies comparing ACS cases with stable CAD patients, miR-21, miR-208a/b, miR-133a/b, miR-30 family, miR-19, and miR-20 were most frequently reported to be dysregulated in ACS. While a number of miRNAs feature consistently across studies in their expression in both ACS and stable CAD, when compared with controls, certain miRNAs were reported as biomarkers specifically in ACS (miR-499, miR-1, miR-133a/b, and miR-208a/b) and stable CAD (miR-215, miR-487a, and miR-502). Thus, miR-21, miR-133, and miR-499 appear to have the most potential as biomarkers to differentiate the diagnosis of ACS from stable CAD, especially miR-499 which showed a correlation between the level of their concentration gradient and myocardial damage. Although these miRNAs are potential diagnostic biomarkers, these findings should be interpreted with caution as the majority of studies conducted predefined candidate-driven assessments of a limited number of miRNAs (PROSPERO registration: CRD42017079744).

Reciprocal Antagonism between MicroRNA-138 and SIRT1 and Its Implications for the Angiogenesis of Endothelial Cells

MicroRNAs and sirtuins are important epigenetic regulators of gene expression and both contribute significantly to postnatal vascular development. However, the crosstalk between miRNAs and sirtuins in the modulation of angiogenesis has rarely been discussed. Here, we investigated the interactions between miR-138 and sirtuins in the process of angiogenesis. We found that overexpression of miR-138 markedly suppressed the proliferation, migration, and tube-forming capacities of the endothelial cells. And, miR-138 inhibitor-treated endothelial cells showed a reversed phenotype. Furthermore, miR-138 plays a negative role in vascular development in vivo. Western blot and qPCR assays demonstrated that SIRT1 was silenced by miR-138, and a luciferase reporter assay showed that miR-138 bound to the 3'-UTR of SIRT1. The re-expression of SIRT1 alleviated miR-138-mediated suppression of angiogenesis. Furthermore, silencing SIRT1 could boost the level of miR-138. And, upon miR-138 inhibitor treatment, SIRT1 silencing no longer reduced the angiogenic ability of endothelial cells significantly. These results demonstrated that the circuitry involving miR-138 and SIRT1 may participate in vascular homeostasis and also offered the possibility of identifying a new approach in the treatment of angiogenic diseases.

miR-24 targets SARS-CoV-2 co-factor Neuropilin-1 in human brain microvascular endothelial cells: Insights for COVID-19 neurological manifestations

Neuropilin-1 is a transmembrane glycoprotein that has been implicated in several processes including angiogenesis and immunity. Recent evidence has also shown that it is implied in the cellular internalization of the severe acute respiratory syndrome coronavirus (SARS-CoV-2), which causes the coronavirus disease 2019 (COVID-19). We hypothesized that specific microRNAs can target Neuropilin-1. By combining bioinformatic and functional approaches, we identified miR-24 as a regulator of Neuropilin-1 transcription. Since Neuropilin-1 has been shown to play a key role in the endothelium-mediated regulation of the blood-brain barrier, we validated miR-24 as a functional modulator of Neuropilin-1 in human brain microvascular endothelial cells (hBMECs), which are the most suitable cell line for an in vitro bloodâ€"brain barrier model.

miR-24 Targets the Transmembrane Glycoprotein Neuropilin-1 in Human Brain Microvascular Endothelial Cells

Neuropilin-1 is a transmembrane glycoprotein that has been implicated in several processes including angiogenesis and immunity. Recent evidence has also shown that it is implied in the cellular internalization of the severe acute respiratory syndrome coronavirus (SARS-CoV-2), which causes the coronavirus disease 2019 (COVID-19). We hypothesized that specific microRNAs can target Neuropilin-1. By combining bioinformatic and functional approaches, we identified miR-24 as a regulator of Neuropilin-1 transcription. Since Neuropilin-1 has been shown to play a key role in the endothelium-mediated regulation of the blood-brain barrier, we validated miR-24 as a functional modulator of Neuropilin-1 in human brain microvascular endothelial cells (hBMECs), which are the most suitable cell line for an in vitro blood-brain barrier model.

Exosomes from microRNA-126 overexpressing mesenchymal stem cells promote angiogenesis by targeting the PIK3R2-mediated PI3K/Akt signalling pathway

microRNA-126 (miR-126), an endothelial-specific miRNA, is associated with vascular homeostasis and angiogenesis. However, the efficiency of miR-126-based treatment is partially compromised due to the low efficiency of miRNA delivery in vivo. Lately, exosomes have emerged as a natural tool for therapeutic molecule delivery. Herein, we investigated whether exosomes derived from bone marrow mesenchymal stem cells (BMMSCs) can be utilized to deliver miR-126 to promote angiogenesis. Exosomes were isolated from BMMSCs overexpressed with miR-126 (Exo-miR-126) by ultracentrifugation. In vitro study, Exo-miR-126 treatment promoted the proliferation, migration and angiogenesis of human umbilical vein endothelial cells (HUVECs). Furthermore, the gene/protein expression of angiogenesis-related vascular endothelial growth factor (VEGF) and angiotensin-1 (Ang-1) were up-regulated after incubation with Exo-miR-126. Additionally, the expression level of phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2) showed an inverse correlation with miR-126 in HUVECs. Particularly, the Exo-miR-126 treatment contributed to enhanced angiogenesis of HUVECs by targeting PIK3R2 to activate the PI3K/Akt signalling pathway. Similarly, Exo-miR-126 administration profoundly increased the number of newly formed capillaries in wound sites and accelerated the wound healing in vivo. The results demonstrate that exosomes derived from BMMSCs combined with miR-126 may be a promising strategy to promote angiogenesis.

Downregulation of miR-126-3p expression contributes to increased inflammatory response in placental trophoblasts in preeclampsia

MiR-126-3p is a prototype of an endothelial miRNA and has protective effects on endothelial cells. However, little is known about the effects of miR-126-3p on placental trophoblasts. In the present study, we tested the hypothesis that aberrant miR-126-3p expression is present in preeclamptic placenta which contributes to increased inflammatory response in trophoblasts. Placentas were obtained immediately after delivery from normotensive and preeclamptic pregnancies. Villous tissue was either fixed with formalin or used for trophoblast isolation. Trophoblast miR-126-3p expression was assessed by in situ hybridization of formalin-fixed tissue sections and by RT-PCR in cultured syncytiotrophoblasts. Culture medium was collected for measurement of IL-6, TNFα, and 8-Isoprostane production by ELISA and total cellular protein was collected for evaluation of HIF1α expression by Western blot. Effects of overexpression of miR-126-3p in trophoblasts on cytokine production were tested by transfection of pre-mir-126, a precursor of miR-126, into primary isolated trophoblasts. We found that downregulation of miR-126-3p expression was associated with increased IL-6 and TNFα production in trophoblasts from preeclamptic placentas vs. normal placentas. Moreover, transient overexpression of miR-126-3p significantly reduced IL-6 and TNFα production in trophoblasts from both normal and preeclamptic placentas. We further found that increase in miR-126-3p expression not only suppressed hypoxia-induced increases in IL-6 and TNFα production, but also attenuated hypoxia-induced increases in HIF1α expression and 8-Isoprostane production in trophoblasts cultured under hypoxic condition. These results provide plausible evidence that downregulation of miR-126-3p expression reduces anti-inflammatory and anti-oxidative stress activities in placental trophoblasts in preeclampsia.

MicroRNA-126 enhances the biological function of endothelial progenitor cells under oxidative stress via PI3K/Akt/GSK3β and ERK1/2 signaling pathways

Endothelial progenitor cell (EPC) transplantation is a safe and effective method to treat acute myocardial infarction (AMI). However, oxidative stress leads to the death of a large number of EPCs in the early stage of transplantation, severely weakening the therapeutic effect. Previous studies demonstrated that microRNAs regulate the biological function of EPCs. The aim of the current study was to investigate the effect of microRNA on the biological function of EPCs under oxidative stress. Quantitative reverse transcription PCR was performed to detect the expression of miR-126, miR-508-5p, miR-150, and miR-16 in EPCs from rats, among which miR-126 showed a relatively higher expression. Treatment with H₂O₂ decreased miR-126 expression in EPCs in a dose-dependent manner. EPCs were further transfected with miR-126 mimics or inhibitors, followed by H₂O₂ treatment. Overexpression of miR-126 enhanced the proliferation, migration, and tube formation of H₂O₂-treated EPCs. MiR-126 overexpression also inhibited reactive oxygen species and malondialdehyde levels and enhanced superoxide dismutase levels, as well as increased angiopoietin (Ang)1 expression and decreased Ang2 expression in H₂O₂-treated EPCs. Moreover, miR-126 participated in the regulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase 3β (GSK3β) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling in EPCs, where both pathways were activated after miR-126 overexpression in H₂O₂-treated EPCs. Overall, we showed that miR-126 promoted the biological function of EPCs under H₂O₂-induced oxidative stress by activating the PI3K/Akt/GSK3β and ERK1/2 signaling pathway, which may serve as a new therapeutic approach to treat AMI.

Intercellular Communication by Vascular Endothelial Cell-Derived Extracellular Vesicles and Their MicroRNAs in Respiratory Diseases

Respiratory diseases and their comorbidities, such as cardiovascular disease and muscle atrophy, have been increasing in the world. Extracellular vesicles (EVs), which include exosomes and microvesicles, are released from almost all cell types and play crucial roles in intercellular communication, both in the regulation of homeostasis and the pathogenesis of various diseases. Exosomes are of endosomal origin and range in size from 50 to 150 nm in diameter, while microvesicles are generated by the direct outward budding of the plasma membrane in size ranges of 100-2,000 nm in diameter. EVs can contain various proteins, metabolites, and nucleic acids, such as mRNA, non-coding RNA species, and DNA fragments. In addition, these nucleic acids in EVs can be functional in recipient cells through EV cargo. The endothelium is a distributed organ of considerable biological importance, and disrupted endothelial function is involved in the pathogenesis of respiratory diseases such as chronic obstructive pulmonary disease, pulmonary hypertension, and acute respiratory distress syndrome. Endothelial cell-derived EVs (EC-EVs) play crucial roles in both physiological and pathological conditions by traveling to distant sites through systemic circulation. This review summarizes the pathological roles of vascular microRNAs contained in EC-EVs in respiratory diseases, mainly focusing on chronic obstructive pulmonary disease, pulmonary hypertension, and acute respiratory distress syndrome. Furthermore, this review discusses the potential clinical usefulness of EC-EVs as therapeutic agents in respiratory diseases.

miR-92a-3p promotes ox-LDL induced-apoptosis in HUVECs via targeting SIRT6 and activating MAPK signaling pathway

Atherosclerosis could be induced by multiple factors, including hypertension, hyperlipidemia, and smoking, and its pathogenesis has not been fully elucidated. MicroRNAs have been shown to possess great anti-atherosclerotic potential, but the precise function of miR-92a-3p in atherosclerosis and its potential molecular mechanism have not been well clarified. Flow cytometry assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT) assay were performed to evaluate effects of oxidized low-density lipoprotein (ox-LDL) on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs), respectively. Malondialdehyde and superoxide dismutase levels in cell lysate were assessed with biochemical kits. The expression levels of miR-92a-3p and Sirtuin6 (SIRT6) in HUVECs exposed to ox-LDL were estimated by real-time quantitative polymerase chain reaction (RT-qPCR). In addition, the protein levels of SIRT6, c-Jun N-terminal kinase (JNK), phosphorylation JNK (p-JNK), p38 mitogen activated protein kinase (p38 MAPK), and phosphorylation p38 MAPK (p-p38 MAPK) were measured by western blot assays. The relationship between miR-92a-3p and SIRT6 was confirmed by dual-luciferase reporter assay. Ox-LDL induced apoptosis and oxidative stress in HUVECs in concentration- and time-dependent manners. Conversely, miR-92a-3p silencing inhibited apoptosis and SIRT6 expression in HUVECs. The overexpression of miR-92a-3p enhanced apoptosis and phosphorylation levels of JNK and p38 MAPK as well as inhibited proliferation in ox-LDL-induced HUVECs. In addition, SIRT6 was a target of miR-92a-3p. miR-92a-3p negatively regulated SIRT6 expression in ox-LDL-induced HUVECs to activate MAPK signaling pathway in vitro. In summary, miR-92a-3p promoted HUVECs apoptosis and suppressed proliferation in ox-LDL-induced HUVECs by targeting SIRT6 expression and activating MAPK signaling pathway.

Cardiac parameters affect prognosis in patients with non-large atherosclerotic infarction

Background

Although large artery atherosclerosis (LAA) is the most common type of cerebral infarction, non-LAA is not uncommon. The purpose of this paper is to investigate the prognosis of patients with non-LAA and to establish a corresponding nomogram.

Patients and methods

Between June 2016 and June 2017, we had 1101 admissions for acute ischemic stroke (AIS). Of these, 848 were LAA and 253 were non-LAA. Patients were followed up every 3 months with a minimum of 1 year of follow-up. After excluding patients who were lost follow-up and patients who did not meet the inclusion criteria, a total of 152 non-LAA patients were included in this cohort study. After single-factor analysis and multifactor logistic regression analysis, the risk factors associated with prognosis were derived and different nomograms were developed based on these risk factors. After comparison, the best model is derived.

Results

Logistics regression found that the patient’s National Institutes of Health Stroke Scale (NIHSS) score, ejection fraction (EF), creatine kinase-MB (CK-MB), age, neutrophil-to-lymphocyte ratio (NLR), aspartate aminotransferase (AST), and serum albumin were independently related to the patient’s prognosis. We thus developed three models: model 1: single NIHSS score, AUC = 0.8534; model 2, NIHSS + cardiac parameters (CK-MB, EF), AUC = 0.9325; model 3, NIHSS + CK−MB + EF + age + AST + NLR + albumin, AUC = 0.9598. We compare the three models: model 1 vs model 2, z = − 2.85, p = 0.004; model 2 vs model 3, z = − 1.58, p = 0.122. Therefore, model 2 is considered to be the accurate and convenient model.

Conclusions

Predicting the prognosis of patients with non-LAA is important, and our nomogram, built on the NIHSS and cardiac parameters, can predict the prognosis accurately and provide a powerful reference for clinical decision making.

Acute ischemic stroke biomarkers: a new era with diagnostic promise?

Stroke is considered as the first cause of neurological dysfunction and second cause of death worldwide. Recombinant tissue plasminogen activator is the only chemical treatment for ischemic stroke approved by the US Food and Drug Administration. It was the only standard of care for a long time with a very narrow therapeutic window, which usually ranges from 3 to 4.5 h of stroke onset; until 2015, when multiple trials demonstrated the benefit of mechanical thrombectomy during the first 6 h. In addition, recent trials showed that mechanical thrombectomy can be beneficial up to 24 h if the patients meet certain criteria including the presence of magnetic resonance imaging/computed tomography perfusion mismatch, which allows better selectivity and higher recruitment of eligible stroke patients. However, magnetic resonance imaging/computed tomography perfusion is not available in all stroke centers. Hence, physicians need other easy and available diagnostic tools to select stroke patients eligible for mechanical thrombectomy. Moreover, stroke management is still challenging for physicians, particularly those dealing with patients with "wake-up" stroke. The resulting brain tissue damage of ischemic stroke and the subsequent pathological processes are mediated by multiple molecular pathways that are modulated by inflammatory markers and post-transcriptional activity. A considerable number of published works suggest the role of inflammatory and cardiac brain-derived biomarkers (serum matrix metalloproteinase, thioredoxin, neuronal and glial markers, and troponin proteins) as well as different biomarkers including the emerging roles of microRNAs. In this review, we assess the accumulating evidence regarding the current status of acute ischemic stroke diagnostic biomarkers that could guide physicians for better management of stroke patients. Our review could give an insight into the roles of the different emerging markers and microRNAs that can be of high diagnostic value in patients with stroke. In fact, the field of stroke research, similar to the field of traumatic brain injury, is in immense need for novel biomarkers that can stratify diagnosis, prognosis, and therapy.