Regulation of angiogenesis by microRNAs in cardiovascular diseases

Chemically Programmed Hydrogels for Spatiotemporal Modulation of the Cardiac Pathological Microenvironment

After myocardial infarction (MI), sustained ischemic events induce pathological microenvironments characterized by ischemia-hypoxia, oxidative stress, inflammatory responses, matrix remodeling, and fibrous scarring. Conventional clinical therapies lack spatially targeted and temporally responsive modulation of the infarct microenvironment, leading to limited myocardial repair. Engineered hydrogels have a chemically programmed toolbox for minimally invasive localization of the pathological microenvironment and personalized responsive modulation over different pathological periods. Chemically programmed strategies for crosslinking interactions, interfacial binding, and topological microstructures in hydrogels enable minimally invasive implantation and in situ integration tailored to the myocardium. This enhances substance exchange and signal interactions within the infarcted microenvironment. Programmed responsive polymer networks, intelligent micro/nanoplatforms, and biological therapeutic cues contribute to the formation of microenvironment-modulated hydrogels with precise targeting, spatiotemporal control, and on-demand feedback. Therefore, this review summarizes the features of the MI microenvironment and chemically programmed schemes for hydrogels to conform, integrate, and modulate the cardiac pathological microenvironment. Chemically programmed strategies for oxygen-generating, antioxidant, anti-inflammatory, provascular, and electrointegrated hydrogels to stimulate iterative and translational cardiac tissue engineering are discussed.

Peripheral whole blood microRNA expression in relation to vascular function: a population-based study

BACKGROUND

As key regulators of gene expression, microRNAs affect many cardiovascular mechanisms and have been associated with several cardiovascular diseases. In this study, we aimed to investigate the relation of whole blood microRNAs with several quantitative measurements of vascular function, and explore their biological role through an integrative microRNA-gene expression analysis.

METHODS

Peripheral whole blood microRNA expression was assessed through RNA-Seq in 2606 participants (45.8% men, mean age: 53.93, age range: 30 to 95 years) from the Rhineland Study, an ongoing population-based cohort study in Bonn, Germany. Weighted gene co-expression network analysis was used to cluster microRNAs with highly correlated expression levels into 14 modules. Through linear regression models, we investigated the association between each module's expression and quantitative markers of vascular health, including pulse wave velocity, total arterial compliance index, cardiac index, stroke index, systemic vascular resistance index, reactive skin hyperemia and white matter hyperintensity burden. For each module associated with at least one trait, one or more hub-microRNAs driving the association were defined. Hub-microRNAs were further characterized through mapping to putative target genes followed by gene ontology pathway analysis.

RESULTS

Four modules, represented by hub-microRNAs miR-320 family, miR-378 family, miR-3605-3p, miR-6747-3p, miR-6786-3p, and miR-330-5p, were associated with total arterial compliance index. Importantly, the miR-320 family module was also associated with white matter hyperintensity burden, an effect partially mediated through arterial compliance. Furthermore, hub-microRNA miR-192-5p was related to cardiac index. Functional analysis corroborated the relevance of the identified microRNAs for vascular function by revealing, among others, enrichment for pathways involved in blood vessel morphogenesis and development, angiogenesis, telomere organization and maintenance, and insulin secretion.

CONCLUSIONS

We identified several microRNAs robustly associated with cardiovascular function, especially arterial compliance and cardiac output. Moreover, our results highlight miR-320 as a regulator of cerebrovascular damage, partly through modulation of vascular function. As many of these microRNAs were involved in biological processes related to vasculature development and aging, our results contribute to the understanding of vascular physiology and provide putative targets for cardiovascular disease prevention.

From Bone Remodeling to Wound Healing: An miR-146a-5p-Loaded Nanocarrier Targets Endothelial Cells to Promote Angiogenesis

Wound healing is a complex challenge that demands urgent attention in the clinical realm. Efficient angiogenesis is a pivotal factor in promoting wound healing. microRNA-146a (miR-146a) inhibitor has angiogenic potential in the periodontal ligament. However, free microRNAs (miRNAs) are poorly delivered into cells due to their limited tissue specificity and low intracellular delivery efficiency. To address this hurdle, we developed a nanocarrier for targeted delivery of the miR-146a inhibitor into endothelial cells. It is composed of a polyethylenimine (PEI)-modified mesoporous silica nanoparticle (MSN) core and a pentapeptide (YIGSR) layer that recognizes endothelial cells. In vitro, we defined that the miR-146a inhibitor and adiponectin (ADP) can modulate angiogenesis and the remodeling of periodontal tissues by activating the ERK and Akt signaling pathways. Then, we confirm the specificity of YIGSR to endothelial cells, and importantly, the nanocarrier effectively delivers the miR-146a inhibitor into endothelial cells, promoting angiogenesis. In a C57 mouse skin wound model, the miR-146a inhibitor is successfully delivered into endothelial cells at the wound site using the nanocarrier, resulting in the formation of new blood vessels with strong CD31 expression. Additionally, no significant differences are found in the expression levels of inflammatory markers interleukin-6 and tumor necrosis factor-α. This outcome not only brings new strategies for angiogenesis but also exhibits broader implications for bone remodeling and wound healing. The breakthrough holds significance for future research and clinical interventions.

Regenerative endodontic therapy: From laboratory bench to clinical practice

BACKGROUND

Maintaining the vitality and functionality of dental pulp is paramount for tooth integrity, longevity, and homeostasis. Aiming to treat irreversible pulpitis and necrosis, there has been a paradigm shift from conventional root canal treatment towards regenerative endodontic therapy.

AIM OF REVIEW

This extensive and multipart review presents crucial laboratory and practical issues related to pulp-dentin complex regeneration aimed towards advancing clinical translation of regenerative endodontic therapy and enhancing human life quality.

KEY SCIENTIFIC CONCEPTS OF REVIEW

In this multipart review paper, we first present a panorama of emerging potential tissue engineering strategies for pulp-dentin complex regeneration from cell transplantation and cell homing perspectives, emphasizing the critical regenerative components of stem cells, biomaterials, and conducive microenvironments. Then, this review provides details about current clinically practiced pulp regenerative/reparative approaches, including direct pulp capping and root revascularization, with a specific focus on the remaining hurdles and bright prospects in developing such therapies. Next, special attention was devoted to discussing the innovative biomimetic perspectives opened in establishing functional tissues by employing exosomes and cell aggregates, which will benefit the clinical translation of dental pulp engineering protocols. Finally, we summarize careful consideration that should be given to basic research and clinical applications of regenerative endodontics. In particular, this review article highlights significant challenges associated with residual infection and inflammation and identifies future insightful directions in creating antibacterial and immunomodulatory microenvironments so that clinicians and researchers can comprehensively understand crucial clinical aspects of regenerative endodontic procedures.

MiR-1909-5p targeting GPX4 affects the progression of aortic dissection by modulating nicotine-induced ferroptosis

OBJECTIVE

Aortic dissection (AD) is a prevalent and acute clinical catastrophe characterized by abrupt manifestation, swift progression, and elevated fatality rates. Despite smoking being a significant risk factor for AD, the precise pathological process remains elusive. This investigation endeavors to explore the mechanisms by which smoking accelerates AD through ferroptosis induction.

METHODOLOGY

In this novel study, we detected considerable endothelial cell death by ferroptosis within the aortic inner lining of both human AD patients with a smoking history and murine AD models induced by β-aminopropionitrile, angiotensin II, and nicotine. Utilizing bioinformatic approaches, we identified microRNAs regulating the expression of the ferroptosis inhibitor Glutathione peroxidase 4 (GPX4). Nicotine's impact on ferroptosis was further assessed in human umbilical vein endothelial cells (HUVECs) through modulation of miR-1909-5p. Additionally, the therapeutic potential of miR-1909-5p antagomir was evaluated in vivo in nicotine-exposed AD mice.

FINDINGS

Our results indicate a predominance of ferroptosis over apoptosis, pyroptosis, and necroptosis in the aortas of AD patients who smoke. Nicotine exposure instigated ferroptosis in HUVECs, where the miR-1909-5p/GPX4 axis was implicated. Modulation of miR-1909-5p in these cells revealed its regulatory role over GPX4 levels and subsequent endothelial ferroptosis. In vivo, miR-1909-5p suppression reduced ferroptosis and mitigated AD progression in the murine model.

CONCLUSIONS

Our data underscore the involvement of the miR-1909-5p/GPX4 axis in the pathogenesis of nicotine-induced endothelial ferroptosis in AD.

Exosomal miR-423-5p Derived from Cerebrospinal Fluid Pulsation Stress-Stimulated Osteoblasts Improves Angiogenesis of Endothelial Cells via DUSP8/ERK1/2 Signaling Pathway

Exosomes secreted from osteoblasts (OBs) can regulate the angiogenesis of endothelial cells (ECs); however, whether cerebrospinal fluid pulsation (CSFP) stress, a special mechanical stimulation, can influence the cell's communication in the context of angiogenesis remains unknown. In this study, the effect of exosomes derived from CSFP stress-stimulated OBs on facilitating the angiogenesis of ECs was investigated. First, OBs were cultured in a CSFP bioreactor, and exosomes derived from OBs were isolated and identified. Cell Counting Kit 8 assay, transwell migration assay, wound healing migration assay, and tube formation assay were conducted to assess the effects of CSFP stress-stimulated OBs-derived exosomes (CSFP-Exos) on the angiogenesis of ECs. Then high-throughput RNA sequencing was used to determine the miRNA profiles of Non-CSFP stress-stimulated OBs-derived exosomes (NCSFP-Exos) and CSFP-Exos, and the luciferase reporter gene assay was performed to confirm the binging of miR-423-5p to DUSP8. In addition, the Matrigel plug assay was performed to explore whether exosomal miR-423-5p has the same effects in vivo. Our results suggested that CSFP-Exos can promote the angiogenesis of ECs, and miR-423-5p was enriched in CSFP-Exos. Moreover, miR-423-5p could promote the effect of angiogenesis via directly targeting dual-specificity phosphatase 8 (DUSP8), which inhibited the ERK1/2 signaling pathway. In conclusion, exosomal miR-423-5p derived from CSFP stress-stimulated OBs could promote the angiogenesis of ECs by the DUSP8/ERK1/2 signaling pathway.

Bibliometric evaluation of global trends and characteristics of RNA methylation during angiogenesis

Background

RNA methylation is involved in major life processes. Angiogenesis is a normal phenomenon that occurs constantly in the bodies of all mammals, once it is aberrant or something goes wrong, it may lead to pathological changes. The bibliometric analysis could produce a comprehensive overview of RNA methylation during angiogenesis.

Methods

The Web of Science Core Collection (WoSCC) database was used to screen publications about RNA methylation during angiogenesis from Jan 1, 2000 to Nov 24, 2022. Bibliometric and visualization analyses were conducted to understand publication trends by CiteSpace and VOSviewer.

Results

In total, 382 publications from 2000 to 2022 were included in the bibliometric and visualization analyses. On the whole, the number of publications had exponential growth. China was the country and Sun Yat-Sen University was the university associated with the largest number of publications, although publications from the United Kingdom and Soochow University were currently having the strongest impact. Cancer was the most studied topic in this field, and N6-methyladenosine is the most studied RNA methylation type.

Conclusion

There is a continuously increasing trend in publications related to RNA methylation and angiogenesis, which has attracted much attention, particularly since 2011. RNA methylation might be a promising target in the investigation of pathological angiogenesis and related disorders, which deserves further investigation.

Remodelers of the vascular microenvironment: The effect of biopolymeric hydrogels on vascular diseases

Vascular disease is the leading health problem worldwide. Vascular microenvironment encompasses diverse cell types, including those within the vascular wall, blood cells, stromal cells, and immune cells. Initiation of the inflammatory state of the vascular microenvironment and changes in its mechanics can profoundly affect vascular homeostasis. Biomedical materials play a crucial role in modern medicine, hydrogels, characterized by their high-water content, have been increasingly utilized as a three-dimensional interaction network. In recent times, the remarkable progress in utilizing hydrogels and understanding vascular microenvironment have enabled the treatment of vascular diseases. In this review, we give an emphasis on the utilization of hydrogels and their advantages in the various vascular diseases including atherosclerosis, aneurysm, vascular ulcers of the lower limbs and myocardial infarction. Further, we highlight the importance and advantages of hydrogels as artificial microenvironments.

High-density lipoprotein regulates angiogenesis by affecting autophagy via miRNA-181a-5p

We previously demonstrated that normal high-density lipoprotein (nHDL) can promote angiogenesis, whereas HDL from patients with coronary artery disease (dHDL) is dysfunctional and impairs angiogenesis. Autophagy plays a critical role in angiogenesis, and HDL regulates autophagy. However, it is unclear whether nHDL and dHDL regulate angiogenesis by affecting autophagy. Endothelial cells (ECs) were treated with nHDL and dHDL with or without an autophagy inhibitor. Autophagy, endothelial nitric oxide synthase (eNOS) expression, miRNA expression, nitric oxide (NO) production, superoxide anion (O2•-) generation, EC migration, and tube formation were evaluated. nHDL suppressed the expression of miR-181a-5p, which promotes autophagy and the expression of eNOS, resulting in NO production and the inhibition of O2•- generation, and ultimately increasing in EC migration and tube formation. dHDL showed opposite effects compared to nHDL and ultimately inhibited EC migration and tube formation. We found that autophagy-related protein 5 (ATG5) was a direct target of miR-181a-5p. ATG5 silencing or miR-181a-5p mimic inhibited nHDL-induced autophagy, eNOS expression, NO production, EC migration, tube formation, and enhanced O2•- generation, whereas overexpression of ATG5 or miR-181a-5p inhibitor reversed the above effects of dHDL. ATG5 expression and angiogenesis were decreased in the ischemic lower limbs of hypercholesterolemic low-density lipoprotein receptor null (LDLr-/-) mice when compared to C57BL/6 mice. ATG5 overexpression improved angiogenesis in ischemic hypercholesterolemic LDLr-/- mice. Taken together, nHDL was able to stimulate autophagy by suppressing miR-181a-5p, subsequently increasing eNOS expression, which generated NO and promoted angiogenesis. In contrast, dHDL inhibited angiogenesis, at least partially, by increasing miR-181a-5p expression, which decreased autophagy and eNOS expression, resulting in a decrease in NO production and an increase in O2•- generation. Our findings reveal a novel mechanism by which HDL affects angiogenesis by regulating autophagy and provide a therapeutic target for dHDL-impaired angiogenesis.

Oleanolic acid rescues critical features of umbilical vein endothelial cells permanently affected by hyperglycemia

Skin wound healing is a physiological process that involves several cell types. Among them, endothelial cells are required for inflammation resolution and neo-angiogenesis, both necessary for tissue restoration after injury. Primary human umbilical vein endothelial cells (C-HUVECs) are derived from the umbilical cord. When women develop gestational diabetes, chronic exposure to hyperglycemia induces epigenetic modifications in these cells (GD-HUVECs), leading to a permanent pro-inflammatory phenotype and impaired angiogenesis in contrast to control cells. Oleanolic acid (OA) is a bioactive triterpenoid known for its epithelial cell migration promotion stimulation and higher tensile strength of wounds. However, the potentially anti-inflammatory and pro-angiogenic properties of OA are still under investigation. We tested OA on C- and GD-HUVECs under inflammatory conditions induced by low levels of the inflammatory cytokine TNF-α. Reduced expression of adhesion molecules VCAM1, ICAM1, and SELE was obtained in OA-pre-treated C- and GD-HUVECs. Additionally, protein VCAM1 levels were also decreased by OA. Coherently, monocyte adhesion assays showed that a lower number of monocytes adhered to GD-HUVEC endothelium under OA pre-treatment when compared to untreated ones. It is noteworthy that OA improved angiogenesis parameters in both phenotypes, being especially remarkable in the case of GD-HUVECs, since OA strongly rescued their poor tube formation behavior. Moreover, endothelial cell migration was improved in C- and GD-HUVECs in scratch assays, an effect that was further confirmed by focal adhesion (FA) remodeling, revealed by paxillin staining on immunocytochemistry assays. Altogether, these results suggest that OA could be an emergent wound healing agent due to its capacity to rescue endothelial malfunction caused by hyperglycemia.

miR-221-3p targets Ang-2 to inhibit the transformation of HCMECs to tip cells

Postembryonic angiogenesis is mainly induced by various proangiogenic factors derived from the original vascular network. Previous studies have shown that the role of Ang-2 in angiogenesis is controversial. Tip cells play a vanguard role in angiogenesis and exhibit a transdifferentiated phenotype under the action of angiogenic factors. However, whether Ang-2 promotes the transformation of endothelial cells to tip cells remains unknown. Our study found that miR-221-3p was highly expressed in HCMECs cultured for 4 h under hypoxic conditions (1% O2 ). Moreover, miR-221-3p overexpression inhibited HCMECs proliferation and tube formation, which may play an important role in hypoxia-induced angiogenesis. By target gene prediction, we further demonstrated that Ang-2 was a downstream target of miR-221-3p and miR-221-3p overexpression inhibited Ang-2 expression in HCMECs under hypoxic conditions. Subsequently, qRT-PCR and western blotting methods were performed to analyse the role of miR-221-3p and Ang-2 on the regulation of tip cell marker genes. MiR-221-3p overexpression inhibited CD34, IGF1R, IGF-2 and VEGFR2 proteins expression while Ang-2 overexpression induced CD34, IGF1R, IGF-2 and VEGFR2 expression in HCMECs under hypoxic conditions. In addition, we further confirmed that Ang-2 played a dominant role in miR-221-3p inhibitors promoting the transformation of HCMECs to tip cells by using Ang-2 shRNA to interfere with miR-221-3p inhibitor-treated HCMECs under hypoxic conditions. Finally, we found that miR-221-3p expression was significantly elevated in both serum and myocardial tissue of AMI rats. Hence, our data showed that miR-221-3p may inhibit angiogenesis after acute myocardial infarction by targeting Ang-2 to inhibit the transformation of HCMECs to tip cells.

Role of exosome-derived miRNAs in diabetic wound angiogenesis

Chronic wounds with high disability are among the most common and serious complications of diabetes. Angiogenesis dysfunction impair wound healing in patients with diabetes. Compared with traditional therapies that can only provide symptomatic treatment, stem cells-owing to their powerful paracrine properties, can alleviate the pathogenesis of chronic diabetic wounds and even cure them. Exosome-derived microRNAs (miRNAs), important components of stem cell paracrine signaling, have been reported for therapeutic use in various disease models, including diabetic wounds. Exosome-derived miRNAs have been widely reported to be involved in regulating vascular function and have promising applications in the repair and regeneration of skin wounds. Therefore, this article aims to review the current status of the pathophysiology of exosome-derived miRNAs in the diabetes-induced impairment of wound healing, along with current knowledge of the underlying mechanisms, emphasizing the regulatory mechanism of angiogenesis, we hope to document the emerging theoretical basis for improving wound repair by restoring angiogenesis in diabetes.

Nano-drug delivery system targeting tumor microenvironment: A prospective strategy for melanoma treatment

Melanoma, the most aggressive form of cutaneous malignancy arising from melanocytes, is frequently characterized by metastasis. Despite considerable progress in melanoma therapies, patients with advanced-stage disease often have a poor prognosis due to the limited efficacy, off-target effects, and toxicity associated with conventional drugs. Nanotechnology has emerged as a promising approach to address these challenges with nanoparticles capable of delivering therapeutic agents specifically to the tumor microenvironment (TME). However, the clinical approval of nanomedicines for melanoma treatment remains limited, necessitating further research to develop nanoparticles with improved biocompatibility and precise targeting capabilities. This comprehensive review provides an overview of the current research on nano-drug delivery systems for melanoma treatment, focusing on liposomes, polymeric nanoparticles, and inorganic nanoparticles. It discusses the potential of these nanoparticles for targeted drug delivery, as well as their ability to enhance the efficacy of conventional drugs while minimizing toxicity. Furthermore, this review emphasizes the significance of interdisciplinary collaboration between researchers from various fields to advance the development of nanomedicines. Overall, this review serves as a valuable resource for researchers and clinicians interested in the potential of nano-drug delivery systems for melanoma treatment and offers insights into future directions for research in this field.

MicroRNA‑378: An important player in cardiovascular diseases (Review)

Cardiovascular disease (CVD) is a common chronic clinical condition and is the main cause of death in humans worldwide. Understanding the genetic and molecular mechanisms involved in the development of CVD is essential to develop effective prevention strategies and therapeutic measures. An increasing number of CVD‑related genetic studies have been conducted, including those on the potential roles of microRNAs (miRs). These studies have demonstrated that miR‑378 is involved in the pathological processes of CVD, including those of myocardial infarction, heart failure and coronary heart disease. Despite the potential importance of miR‑378 CVD, a comprehensive summary of the related literature is lacking. Thus, the present review aimed to summarize the findings of previous studies on the roles and mechanisms of miR‑378 in a variety of CVDs and provide an up‑to date basis for further r research targeting the prevention and treatment of CVDs.

Post-Transcriptional and Epigenetic Regulation of Estrogen Signaling

Post-translational and epigenetic regulation are important mechanisms controlling functions of genes and proteins. Although the "classic" estrogen receptors (ERs) have been acknowledged to function in mediating estrogen effects via transcriptional mechanisms, estrogenic agents modulate the turnover of several proteins via post-transcriptional and post-translational pathways including epigenetics. For instance, the metabolic and angiogenic action of G-protein coupled estrogen receptor (GPER) in vascular endothelial cells has been recently elucidated. By interacting with GPER, 17β-estradiol and the GPER agonist G1 enhance endothelial stability of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) and capillary tube formation by increasing ubiquitin-specific peptidase 19 levels, thereby reducing PFKFB3 ubiquitination and proteasomal degradation. In addition to ligands, the functional expression and trafficking of ERs can be modulated by post-translational modification, including palmitoylation. MicroRNAs (miRNAs), the most abundant form of endogenous small RNAs in humans, regulate multiple target genes and are at the center of the multi-target regulatory network. This review also discusses the emerging evidence of how miRNAs affect glycolytic metabolism in cancer, as well as their regulation by estrogens. Restoring dysregulated miRNA expression represents a promising strategy to counteract the progression of cancer and other disease conditions. Accordingly, estrogen post-transcriptional regulatory and epigenetic mechanisms represent novel targets for pharmacological and nonpharmacological intervention for the treatment and prevention of hormone-sensitive noncommunicable diseases, including estrogen-sensitive cancers of the reproductive system in women. SIGNIFICANCE STATEMENT: The effects of estrogen are mediated by several mechanisms that are not limited to the transcriptional regulation of target genes. Slowing down the turnover of master regulators of metabolism by estrogens allows cells to rapidly adapt to environmental cues. Identification of estrogen-targeted microRNAs may lead to the development of novel RNA therapeutics that disrupt pathological angiogenesis in estrogen-dependent cancers.

The miR-148/152 family contributes to angiogenesis of human pluripotent stem cell- derived endothelial cells by inhibiting MEOX2

Human pluripotent stem cell-derived endothelial cells (hPSC-ECs) represent a promising source of human ECs urgently needed for the study of cardiovascular disease mechanisms, cell therapy, and drug screening. This study aims to explore the function and regulatory mechanism of the miR-148/152 family consisting of miR-148a, miR-148b, and miR-152 in hPSC-ECs, so as to provide new targets for improving EC function during the above applications. In comparison with the wild-type (WT) group, miR-148/152 family knockout (TKO) significantly reduced the endothelial differentiation efficiency of human embryonic stem cells (hESCs), and impaired the proliferation, migration, and capillary-like tube formatting abilities of their derived ECs (hESC-ECs). Overexpression of miR-152 partially restored the angiogenic capacity of TKO hESC-ECs. Furthermore, the mesenchyme homeobox 2 (MEOX2) was validated as the direct target of miR-148/152 family. MEOX2 knockdown resulted in partial restoration of the angiogenesis ability of TKO hESC-ECs. The Matrigel plug assay further revealed that the in vivo angiogenic capacity of hESC-ECs was impaired by miR-148/152 family knockout, and increased by miR-152 overexpression. Thus, the miR-148/152 family is crucial for maintaining the angiogenesis ability of hPSC-ECs, and might be used as a target to enhance the functional benefit of EC therapy and promote endogenous revascularization.

Cardiac angiogenesis enhances by activating Mir-126 and related target proteins in type 2 diabetic rats: Rescue combination effect of Sodium butyrate and voluntary exercise therapy

Objective

type 2 diabetes, metabolic disorder, is one of the main risk factors for cardiovascular disease, leading to angiogenesis injury. The present study wanted to discover the effect of sodium butyrate (NaB) and voluntary exercise, alone or together, on miR-126 and related proteins in rats with type 2 diabetes.

Methods

thirty-five male Wistar rats (200-250 g) were randomly divided into five groups: control, diabetes, diabetes-NaB, diabetes-exercise, and diabetes-NaB-exercise. Type 2 diabetes was induced by intraperitoneal injection of streptozotocin (35 mg/kg) and high-fat diet. The rats were then administrated NaB (200 mg/kg. ip) or were subjected to voluntary exercise, or combined NaB and voluntary exercise for 8 weeks. MiR-126 expression in the cardiac tissue was determined by real-time PCR, and the SPRED-1 and RAF proteins expression levels were measured by western blot.

Results

NaB and voluntary exercise up-regulated cardiac miR-126 and RAF expression levels and down-regulated SPRED-1 in cardiac tissue of type 2 diabetic rats. Moreover, the combination of NaB and voluntary exercise amplified their effects on those parameters. Both NaB and voluntary exercise or together markedly modulated serum glucose and HbA1c.

Conclusion

The present findings demonstrated that NaB combined with exercise could improve cardiac angiogenesis by increasing miR-126 and affecting related proteins. Thus, NaB together with voluntary exercise might be a promising intervention for the treatment and prevention of type 2 diabetes.

miR-1322 protects against the myocardial ischemia via LRP8/PI3K/AKT pathway

INTRODUCTION

Myocardial infarction is a fatal disease that causes millions of deaths worldwide every year. The damage and recovery of cardiomyocytes are closely related to changes in gene expression. miRNA may be a new therapeutic target of myocardial ischemia-reperfusion.

METHODS

The differential expression genes were analyzed based on GSE83500, GSE60993 and GSE154733. miRNA expression profile data and clinical data were downloaded from GSE76591. Bioinformatics analysis including limma package, cluster analysis, WGCNA analysis were performed. H9c2 cell hypoxia model and mouse myocardial ischemia model were established. Q-PCR, Western blot and luciferase assay were carried out.

RESULTS

miR-1322 was identified as a significantly differentially expressed miRNA in myocardial ischemi. Yin Yang 1(YY1) was significantly highly expressed in cells with hypoxia treatment (P < 0.05), and myocardial ischemia mice (P < 0.01), which was identified as the transcription factor of miR-1322. The protein expression of LRP8 was lower in cells with hypoxia treatment and myocardial ischemia mice (P < 0.05) and LRP8 was the target gene of miR-1322. The overexpression of LRP8 could significantly increase the expression of p-PI3K, p-AKT, and P70 S6K (P < 0.05). LRP8 regulated PI3K/AKT/P70 S6K signaling pathway, eventually resulting in cell apoptosis.

CONCLUSION

Our results suggested that miR-1322 can protect against the myocardial ischemia via LRP8/PI3K/AKT pathway.

New insights into circRNA and its mechanisms in angiogenesis regulation in ischemic stroke: a biomarker and therapeutic target

Ischemic stroke accounts for about 71% of strokes worldwide. Due to limited recommended therapeutics for ischemic stroke, more attention is focused on angiogenesis in ischemic stroke. Not long after ischemic stroke, angiogenesis arises and is vital for the prognosis. Various pro-angiogenic, anti-angiogenic factors and their downstream pathways engage in angiogenesis regulation. CircRNAs are differentially expressed after ischemic stroke. Up to now, circRNAs have been found to exert many functions in regulating apoptosis, autophagy, proliferation, and differentiation of neurons and neural stem cells mainly as miRNAs sponges or proteins decoy. Thus, many circRNAs are considered promising biomarkers or therapeutic targets for ischemic stroke. Besides, circRNAs participate in the modulation of endothelial-mesenchymal transition and blood-brain barrier maintenance. Moreover, circRNAs play significant roles in endothelial dysfunction concerning inflammation responses, apoptosis, proliferation, and migration. They correlate with many angiogenesis-related signaling pathways and genes via the circRNA/miRNA/mRNA network. Novel insights into circRNAs significance in angiogenesis regulation in ischemic stroke could be provided for further researches on the clinical application of circRNAs in ischemic stroke.

RNA-binding proteins and translation control in angiogenesis

Tissue vascularization through the process of angiogenesis ensures adequate oxygen and nutrient supply during development and regeneration. The complex morphogenetic events involved in new blood vessel formation are orchestrated by a tightly regulated crosstalk between extra and intracellular factors. In this context, RNA-binding protein (RBP) activity and protein translation play fundamental roles during the cellular responses triggered by particular environmental cues. A solid body of work has demonstrated that key RBPs (such as HuR, TIS11 proteins, hnRNPs, NF90, QKIs and YB1) are implicated in both physiological and pathological angiogenesis. These RBPs are critical for the metabolism of messenger (m)RNAs encoding angiogenic modulators and, importantly, strong evidence suggests that RBP-mRNA interactions can be altered in disease. Lesser known, but not less important, the mechanistic aspects of protein synthesis can also regulate the generation of new vessels. In this review, we outline the key findings demonstrating the implications of RBP-mediated RNA regulation and translation control in angiogenesis. Furthermore, we highlight how these mechanisms of post-transcriptional control of gene expression have led to promising therapeutic strategies aimed at targeting undesired blood vessel formation.

Metformin Prevents Endothelial Dysfunction in Endometriosis through Downregulation of ET-1 and Upregulation of eNOS

This study aimed to evaluate if the treatment with metformin affects the morphologic structure, endothelial function, angiogenesis, inflammation and oxidation-responsive pathways in the heart of mice with surgically induced endometriosis. B6CBA/F1 mice (n = 37) were divided into four groups; Sham (S), Metformin (M), Endometriosis (E) and Metformin/Endometriosis (ME). The cross-sectional area of cardiomyocytes was assessed after Hematoxylin-Eosin staining and fibrosis after Picrosirius-Red staining. ET-1, nitric oxide synthases-iNOS and eNOS, and VEGF and VEGFR-2 were detected by immunofluorescence. Semi-quantification of ET-1, eNOS, VEGF, NF-kB, Ikβα and KEAP-1 was performed by Western blotting. MIR199a, MIR16-1, MIR18a, MIR20a, MIR155, MIR200a, MIR342, MIR24-1 and MIR320a were quantified by Real-Time qPCR. The interaction of endometriosis and metformin effects was assessed by a two-way ANOVA test. Compared with the other groups, M-treated mice presented a higher cross-sectional area of cardiomyocytes. Heart fibrosis increased with endometriosis. Treatment of endometriosis with metformin in the ME group downregulates ET-1 and upregulates eNOS expression comparatively with the E group. However, metformin failed to mitigate NF-kB expression significantly incremented by endometriosis. The expression of MIR199a, MIR16-1 and MIR18a decreased with endometriosis, whereas MIR20a showed an equivalent trend, altogether reducing cardioprotection. In summary, metformin diminished endometriosis-associated endothelial dysfunction but did not mitigate the increase in NF-kB expression and cardiac fibrosis in mice with endometriosis.

Phenformin suppresses angiogenesis through the regulation of exosomal microRNA-1246 and microRNA-205 levels derived from oral squamous cell carcinoma cells

Exosomes secreted by cancer cells are important components in the tumor microenvironment, enabling cancer cells to communicate with each other and with noncancerous cells to play important roles in tumor progression and metastasis. Phenformin, a biguanide antidiabetic drug, has been reported to have a strong antitumor function in multiple types of cancer cells, however little research has been reported about whether phenformin can regulate the secretion of exosomes by cancer cells to regulate the tumor microenvironment and contribute to its antitumor function. Here we found that exosomes (Phen-Exo) derived from phenformin-treated oral squamous cell carcinoma (OSCC) cells significantly suppress the proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro. The inhibition of angiogenesis by Phen-Exo was verified in vivo by matrigel plug angiogenesis assays and by chick chorioallantoic membrane assays. Mechanistically, we discovered that the expression of microRNA-1246 (miR-1246) and microRNA-205 (miR-205) was significantly increased in exosomes secreted by OSCC cells treated with phenformin, while high expression levels of miR-1246 or miR-205 in vascular endothelial cells inhibited their angiogenic effects and decreased expression of the angiogenic factor VEGFA. In conclusion, these results reveal that phenformin can inhibit angiogenesis by regulating the levels of miR-1246 and miR-205 in exosomes secreted by OSCC cells, suggesting that phenformin has the potential to alter the tumor microenvironment to antagonize the growth of OSCCs, which provides a theoretical basis for developing new strategies to treat OSCCs in the future.

The Role of Connexin in Ophthalmic Neovascularization and the Interaction between Connexin and Proangiogenic Factors

The formation of new blood vessels is an important physiological process that occurs during development. When the body is injured, new blood vessel formation helps the body recuperate by supplying more oxygen and nutrients. However, this mechanism can have a negative effect. In ophthalmologic diseases, such as corneal new blood vessels, neonatal vascular glaucoma, and diabetes retinopathy, the formation of new blood vessels has become a critical component in patient survival. Connexin is a protein that regulates the cellular and molecular material carried by cells. It has been demonstrated that it is widely expressed in vascular endothelial cells, where it forms a slit connection between adjacent cells to promote cell-cell communication via hemichannels, as well as substance exchange into intracellular environments. Numerous studies have demonstrated that connexin in vascular endothelial cells plays an important role in angiogenesis and vascular leakage. The purpose of this study was to investigate the effect between the angiogenesis-associated factor and the connexin. It also reveals the effect of connexin on ophthalmic neovascularization.

Integrated Analysis of Angiogenesis Related lncRNA-miRNA-mRNA in Patients With Coronary Chronic Total Occlusion Disease

Background: Coronary chronic total occlusion (CTO) disease is common and its specific characteristic is collateral formation. The Integrated analysis of angiogenesis related lncRNA-miRNA-mRNA network remains unclear and might provide target for future studies.

Methods: A total of five coronary artery disease (control group) and five CTO (CTO group) patients were selected for deep RNA and miRNA sequencing. The expression profiles of lncRNAs, mRNAs circRNA and miRNAs were obtained. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were then performed. The expression of a 14q32 miRNA gene cluster, including miRNA-494, miRNA-495 and miRNA-329, were selected to be determined in another larger patient cohort. Analysis of the lncRNA-miRNA495-mRNA network was constructed to find potential targets for future studies.

Results: A total of 871 lncRNAs, 1,080 mRNAs, 138 circRNAs and 56 miRNAs were determined as differentially expressed (DE) in CTO patients compared with control patients. GO and KEGG analyses revealed that the top terms included MAPK signaling pathway, HIF-1 signaling pathway, EGFR tyrosine kinase inhibitor resistance, embryonic organ development, wound healing, MAPK signaling pathway and JAK-STAT signaling pathway, which are related to angiogenesis. The expression of miRNA-494, miRNA-495 and miRNA-329 were all significantly down-regulated in CTO patients and they were confirmed to be down-regulated in another cohort of 68 patients. Then we divided the CTO patients into two groups according to CC grade (poor CC group, CC = 0 or one; good CC group, CC = 2). MiRNA-494, miRNA-495 and miRNA-329 were found to be down-regulated in good CC group compared with poor CC group. Analysis of the lncRNA-miRNA495-mRNA network showed 3 DE lncRNA sponges (NONHSAG008675, NONHSAG020957 and NONHSAG010989), 4 DE lncRNA targets (NONHSAT079547.2, NONHSAT081776.2, NONHSAT148555.1 and NONHSAT150928.1) and 2 DE mRNA targets (RAD54L2 and ZC3H4) of miRNA495.

Conclusion: This study revealed that the lncRNA-miRNA-mRNA network might play a critical role in angiogenesis in CTO patients.

Exosomes derived from stem cells of human deciduous exfoliated teeth inhibit angiogenesis in vivo and in vitro via the transfer of miR-100-5p and miR-1246

Background

Anti-angiogenic therapy has been shown to be a promising strategy for anti-tumor treatment. Increasing evidence indicates that tumor angiogenesis is affected by exosomes that are secreted by mesenchymal stem cells (MSCs), but whether exosomes derived from MSCs suppress or promote angiogenesis remain paradoxical. The purpose of this study focused on understanding the potential role of exosomes derived from stem cells of human deciduous exfoliated teeth (SHED-Exos) in regulating angiogenesis and the underlying molecular mechanism.

Methods

Exosomes were isolated from supernatants of SHED cells using an exosome purification kit and were characterized by transmission electron microscopy, nanoparticle tracking analysis and western blot analysis. Cell Counting Kit-8, flow cytometric assays, western blots, wound healing and transwell migration assays were performed to characterize the roles of SHED-Exos on cell proliferation, apoptosis and migration of human umbilical vein endothelial cells (HUVECs). The anti-angiogenic activity of SHED-Exos was assessed via a tube formation assay of endothelial cells and angiogenesis-related factors were analyzed by western blotting. In vivo, we used the chick chorioallantoic membrane (CAM) assay and an oral squamous cell carcinoma (OSCC) xenograft transplantation model with nude mice that received multi-point injections at three-day intervals to evaluate the effects on angiogenesis. Furthermore, the sequencing of microRNAs (miRNAs) in SHED-Exos was performed to investigate the underlying anti-angiogenic mechanism.

Results

The results showed that SHED-Exos inhibit cell proliferation and migration and induce apoptosis in HUVECs. SHED-Exos suppress the tube-like structure formation of HUVECs in vitro. SHED-Exos downregulate several angiogenesis-related factors, including VEGFA, MMP-9 and ANGPT1. In vivo, the chick CAM assay verified that treatment with SHED-Exos inhibits micro-vascular formation, and importantly, significantly reduces the micro-vascular formation of tumors generated from xenografted OSCC cells, which was associated with the inhibition of tumor growth in vivo. Mechanistically, our data suggested that SHED-Exos are enriched with miR-100-5p and miR-1246 and are transferred to endothelial cells, which results in decreased tube formation via the down-regulation of VEGFA expression.

Conclusions

These results demonstrate that SHED-Exos inhibit angiogenesis in vitro and in vivo, which suggests that SHED-Exos could potentially serve as a novel and effective therapeutic approach for anti-angiogenic treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02764-9.

Profiling of exosomal microRNAs expression in umbilical cord blood from normal and preeclampsia patients

Background

Epidemiological and experimental studies suggest that preeclampsia has a negative impact on maternity and offspring health. Previous studies report that dysregulation in utero-environment increases risk for elderly disease such as cardiovascular disease. However, the underlying mechanisms remain elusive. Specific microRNAs (miRNAs) are packaged in exosomes may regulate microvascular dysfunction in offspring of mothers with preeclampsia. The present study aimed to identify the differential expression profiles of microRNAs in the serum exosomes between patients with preeclampsia and normal pregnancies.

Methods

A comprehensive miRNA sequence-based approach was performed to compare exosomes carry miRNAs (Exo-miRNAs) expression levels in umbilical serum between normal and preeclampsia patients. Exosomes were isolated using the ExoQuick precipitation kit. Serum exosomes were then viewed under electron microscopy, and their characteristics determined by western blotting and nanoparticle-tracking analysis. Illumina platform was used to perform sequencing. Bioinformatics analysis was used to explore differentially expressed Exo-miRNAs in umbilical serum.

Results

Based on sequence similarity, 1733 known miRNAs were retrieved. Furthermore, 157 mature miRNAs in serum exosomes were significantly differential expressed between PE and those control groups (P<0.05, log₂|FC| > 1). Out, of the 157 miRNAs, 96 were upregulated miRNAs whereas 61 miRNAs were downregulated. The 157 differentially expressed miRNAs targeted 51,424 differentially expressed genes. Functional analysis through KEGG pathway and Gene Ontology results uncovered that target genes of miRNAs with differential expression were significantly linked to several pathways and biological processes.

Conclusion

The findings of this study showed differential expression of umbilical serum Exo-miRNAs in normal compared with PE patients, implying that these Exo-miRNAs may associate with microvascular dysfunction in offspring of mothers with preeclampsia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04449-w.

The miR-133b/brefeldin A-inhibited guanine nucleotide-exchange protein 1 (ARFGEF1) axis represses proliferation, invasion, and migration in cervical cancer cells

Cervical cancer is a common gynecological malignancy, and miR-133b is an abnormally expressed cervical cancer gene, which suggests that miR-133b may be involved in the occurrence and development of cervical cancer. However, the underlying mechanism is still unclear. miR-133b was overexpressed or silenced in the cervical cancer cell line C33A. Brefeldin A-inhibited guanine nucleotide-exchange protein 1 (ARFGEF1) was combined with overexpression of miR-133b in C33A cells. Cell Counting Kit-8, clone formation, and Transwell assays were performed to determine the influence of miR-133b and ARFGEF1 on clone formation, proliferation, migration, and invasion of C33A cells. The interaction between miR-133b and ARFGEF1 was verified using a luciferase reporter assay. Finally, the mRNA and protein expression of miR-133b and ARFGEF1 in the tumor and adjacent normal tissues of cervical cancer patients was detected by real-time quantitative PCR, Western blotting, and immunohistochemistry. The results indicated that miR-133b up-regulation suppressed the proliferation, invasion, migration, and clone formation abilities of C33A cells (P < 0.05). However, silence of miR-133b promoted the proliferation, invasion, and migration of C33A cells (P < 0.05). Clone formation ability of C33A cells was also elevated by miR-133b deficiency (P < 0.05). Moreover, miR-133b interacted with ARFGEF1 and repressed ARFGEF1 expression in C33A cells (P < 0.05). ARFGEF1 overexpression weakened miR-133b overexpression-mediated inhibition of proliferation, invasion, and migration of C33A cells (P < 0.05). miR-133b expression was decreased, and ARFGEF1 was up-regulated in tumor tissues of cervical cancer patients (P < 0.05). All results revealed that miR-133b suppresses cervical cancer progression by inhibiting proliferation, invasion, and migration of cervical cancer cells via targeting ARFGEF1. Thus, our study determined the mechanism of miR-133b in cervical cancer, and confirmed miR-133b/ARFGEF1 may become a potential therapeutic target for cervical cancer.

Advances in miR-132-Based Biomarker and Therapeutic Potential in the Cardiovascular System

Atherosclerotic cardiovascular disease and subsequent heart failure threaten global health and impose a huge economic burden on society. MicroRNA-132 (miR-132), a regulatory RNA ubiquitously expressed in the cardiovascular system, is up-or down-regulated in the plasma under various cardiac conditions and may serve as a potential diagnostic or prognostic biomarker. More importantly, miR-132 in the myocardium has been demonstrated to be a master regulator in many pathological processes of ischemic or nonischemic heart failure in the past decade, such as myocardial hypertrophy, fibrosis, apoptosis, angiogenesis, calcium handling, neuroendocrine activation, and oxidative stress, through downregulating target mRNA expression. Preclinical and clinical phase 1b studies have suggested antisense oligonucleotide targeting miR-132 may be a potential therapeutic approach for ischemic or nonischemic heart failure in the future. This review aims to summarize recent advances in the physiological and pathological functions of miR-132 and its possible diagnostic and therapeutic potential in cardiovascular disease.

MiR-191-5p Disturbed the Angiogenesis in a Mice Model of Cerebral Infarction by Targeting Inhibition of BDNF

BACKGROUND

miRNAs are crucial regulators of angiogenesis, but there have been no detailed studies on the role of miR-191-5p in cerebral infarct angiogenesis. Here, we investigated the role of miR-191-5p in regulating cerebral infarction angiogenesis.

MATERIAL AND METHODS

Mice were injected intracerebroventricularly with antagomir negative control (NC-antagomir), miR-191-5p antagomir, or pcDNA-BDNF 2 h before middle cerebral artery occlusion (MCAO), followed by neurobehavioral score and foot-fault test. The cerebral infarct volume was performed by TTC staining. The microvessel density was detected by FITC-dextran. RT-qPCR was used to detect the levels of miR-191-5p and its target gene BDNF. Western blotting was applied to detect the protein levels of BDNF. The luciferase reporter assay verified that miR-191-5p targeted BDNF.

RESULTS

We found an increased level of miR-191-5p in the brain tissue of mice to MCAO. Down-regulation of miR-191-5p reduced the infarct volume and ameliorated neurological deficits in MCAO mice. Further investigation showed that miR-191-5p directly targeted BDNF and that the protective effect of miR-191-5p inhibition in angiogenesis was achieved by regulating BDNF.

CONCLUSIONS

Our results indicated that miR-191-5p disturbed the angiogenesis in the mouse models of cerebral infarction by inhibiting BDNF.

The Expression Regulatory Network in the Lung Tissue of Tibetan Pigs Provides Insight Into Hypoxia-Sensitive Pathways in High-Altitude Hypoxia

To adapt to a low-oxygen environment, Tibetan pigs have developed a series of unique characteristics and can transport oxygen more effectively; however, the regulation of the associated processes in high-altitude animals remains elusive. We performed mRNA-seq and miRNA-seq, and we constructed coexpression regulatory networks of the lung tissues of Tibetan and Landrace pigs. HBB, AGT, COL1A2, and EPHX1 were identified as major regulators of hypoxia-induced genes that regulate blood pressure and circulation, and they were enriched in pathways related to signal transduction and angiogenesis, such as HIF-1, PI3K-Akt, mTOR, and AMPK. HBB may promote the combination of hemoglobin and oxygen as well as angiogenesis for high-altitude adaptation in Tibetan pigs. The expression of MMP2 showed a similar tendency of alveolar septum thickness among the four groups. These results indicated that MMP2 activity may lead to widening of the alveolar wall and septum, alveolar structure damage, and collapse of alveolar space with remarkable fibrosis. These findings provide a perspective on hypoxia-adaptive genes in the lungs in addition to insights into potential candidate genes in Tibetan pigs for further research in the field of high-altitude adaptation.

Role of the Purinergic P2Y2 Receptor in Pulmonary Hypertension

Pulmonary arterial hypertension (PAH), group 1 pulmonary hypertension (PH), is a fatal disease that is characterized by vasoconstriction, increased pressure in the pulmonary arteries, and right heart failure. PAH can be described by abnormal vascular remodeling, hyperproliferation in the vasculature, endothelial cell dysfunction, and vascular tone dysregulation. The disease pathomechanisms, however, are as yet not fully understood at the molecular level. Purinergic receptors P2Y within the G-protein-coupled receptor family play a major role in fluid shear stress transduction, proliferation, migration, and vascular tone regulation in systemic circulation, but less is known about their contribution in PAH. Hence, studies that focus on purinergic signaling are of great importance for the identification of new therapeutic targets in PAH. Interestingly, the role of P2Y2 receptors has not yet been sufficiently studied in PAH, whereas the relevance of other P2Ys as drug targets for PAH was shown using specific agonists or antagonists. In this review, we will shed light on P2Y receptors and focus more on the P2Y2 receptor as a potential novel player in PAH and as a new therapeutic target for disease management.

Mesenchymal Stem Cell Exosomes in the Treatment of Myocardial Infarction: a Systematic Review of Preclinical In Vivo Studies

Several prior studies have highlighted the promise of mesenchymal stem cells (MSCs) as tools for treating myocardial infarction (MI) patients. While MSCs were initially thought to mediate post-MI repair through differentiation and replacement of injured cells, they are now thought to function by releasing exosomes carrying important cargos which can prevent apoptosis and facilitate revascularization in the context of MI. Herein, we comprehensively survey prior preclinical studies examining MSC-derived exosomes (MSC-Exos) utility for the repair of MI-related tissue injury. In total, 24 relevant studies were identified in the PubMed, Web of Science, Embase, and Cochrane Library databases as per the PRISMA guidelines. In most studies, exosome-treated rodents exhibited improved cardiac function and angiogenesis together with decreased apoptotic cell death. MSC-Exos thus offer beneficial therapeutic efficacy when treating MI injury. However, further work will be necessary to standardize experimental preclinical models and to validate these results. This systematic review provides a comprehensive overview of previous preclinical studies on the utility of exosomes derived from mesenchymal stem cells (MSCs) in the repair of myocardial infarction (MI) injury.

Notch activation promotes endothelial quiescence by repressing MYC expression via miR-218

After angiogenesis-activated embryonic and early postnatal vascularization, endothelial cells (ECs) in most tissues enter a quiescent state necessary for proper tissue perfusion and EC functions. Notch signaling is essential for maintaining EC quiescence, but the mechanisms of action remain elusive. Here, we show that microRNA-218 (miR-218) is a downstream effector of Notch in quiescent ECs. Notch activation upregulated, while Notch blockade downregulated, miR-218 and its host gene Slit2, likely via transactivation of the Slit2 promoter. Overexpressing miR-218 in human umbilical vein ECs (HUVECs) significantly repressed cell proliferation and sprouting in vitro. Transcriptomics showed that miR-218 overexpression attenuated the MYC proto-oncogene, bHLH transcription factor (MYC, also known as c-myc) signature. MYC overexpression rescued miR-218-mediated proliferation and sprouting defects in HUVECs. MYC was repressed by miR-218 via multiple mechanisms, including reduction of MYC mRNA, repression of MYC translation by targeting heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), and promoting MYC degradation by targeting EYA3. Inhibition of miR-218 partially reversed Notch-induced repression of HUVEC proliferation and sprouting. In vivo, intravitreal injection of miR-218 reduced retinal EC proliferation accompanied by MYC repression, attenuated pathological choroidal neovascularization, and rescued retinal EC hyper-sprouting induced by Notch blockade. In summary, miR-218 mediates the effect of Notch activation of EC quiescence via MYC and is a potential treatment for angiogenesis-related diseases.

Exosomes from adipose-derived stem cells alleviate myocardial infarction via microRNA-31/FIH1/HIF-1α pathway

Our previous study has revealed that exosomes from adipose-derived stem cells (ASCs) promote angiogenesis in subcutaneously transplanted gels by delivery of microRNA-31 (miR-31) which targets factor inhibiting hypoxia-inducible factor-1 (FIH1) in recipient cells. Here we hypothesized that ASC exosomes alleviate ischemic diseases through miR-31/FIH1/hypoxia-inducible factor-1α (HIF-1α) signaling pathway. Exosomes from ASCs were characterized with nanoparticle tracking analysis, transmission electron microscopy, and immunoblotting analysis for exosomal markers. Results from immunoblotting and laser imaging of ischemic mouse hindlimb revealed that miR-31 enriched ASC exosomes inhibited FIH1 expression and enhanced the blood perfusion, respectively. These effects were impaired when using miR-31-depleted exosomes. Immunohistochemistry analysis showed that administration of exosomes resulted in a higher arteriole density and larger CD31⁺ area in ischemic hindlimb than miR-31-delpleted exosomes. Similarly, knockdown of miR-31 in exosomes reduced the effects of the exosomes on increasing ventricular fraction shortening and CD31⁺ area, and on decreasing infarct size. Exosomes promoted endothelial cell migration and tube formation. These changes were attenuated when miR-31 was depleted in the exosomes or when FIH1 was overexpressed in the endothelial cells. Furthermore, the results from immunocytochemistry, co-immunoprecipitation, and luciferase reporter assay demonstrated that the effects of exosomes on nuclear translocation, binding with co-activator p300, and activation of HIF-1α were decreased when miR-31 was depleted in the exosomes or FIH1 was overexpressed. Our findings provide evidence that exosomes from ASCs promote angiogenesis in both mouse ischemic hindlimb and heart through transport of miR-31 which targets FIH1 and therefore triggers HIF-1α transcriptional activation.

MiRNAs and Cancer: Key Link in Diagnosis and Therapy

Since the discovery of the first microRNA (miRNA), the exploration of miRNA biology has come to a new era in recent decades. Monumental studies have proven that miRNAs can be dysregulated in different types of cancers and the roles of miRNAs turn out to function to either tumor promoters or tumor suppressors. The interplay between miRNAs and the development of cancers has grabbed attention of miRNAs as novel tools and targets for therapeutic attempts. Moreover, the development of miRNA delivery system accelerates miRNA preclinical implications. In this review, we depict recent advances of miRNAs in cancer and discuss the potential diagnostic or therapeutic approaches of miRNAs.

A hybrid CNN-LSTM model for pre-miRNA classification

miRNAs (or microRNAs) are small, endogenous, and noncoding RNAs construct of about 22 nucleotides. Cumulative evidence from biological experiments shows that miRNAs play a fundamental and important role in various biological processes. Therefore, the classification of miRNA is a critical problem in computational biology. Due to the short length of mature miRNAs, many researchers are working on precursor miRNAs (pre-miRNAs) with longer sequences and more structural features. Pre-miRNAs can be divided into two groups as mirtrons and canonical miRNAs in terms of biogenesis differences. Compared to mirtrons, canonical miRNAs are more conserved and easier to be identified. Many existing pre-miRNA classification methods rely on manual feature extraction. Moreover, these methods focus on either sequential structure or spatial structure of pre-miRNAs. To overcome the limitations of previous models, we propose a nucleotide-level hybrid deep learning method based on a CNN and LSTM network together. The prediction resulted in 0.943 (%95 CI ± 0.014) accuracy, 0.935 (%95 CI ± 0.016) sensitivity, 0.948 (%95 CI ± 0.029) specificity, 0.925 (%95 CI ± 0.016) F1 Score and 0.880 (%95 CI ± 0.028) Matthews Correlation Coefficient. When compared to the closest results, our proposed method revealed the best results for Acc., F1 Score, MCC. These were 2.51%, 1.00%, and 2.43% higher than the closest ones, respectively. The mean of sensitivity ranked first like Linear Discriminant Analysis. The results indicate that the hybrid CNN and LSTM networks can be employed to achieve better performance for pre-miRNA classification. In future work, we study on investigation of new classification models that deliver better performance in terms of all the evaluation criteria.

The Effects on Angiogenesis of Relevant Inorganic Chemotherapeutics

Angiogenesis is a key process allowing the formation of blood vessels. It is crucial for all the tissues and organs, ensuring their function and growth. Angiogenesis is finely controlled by several mechanisms involving complex interactions between pro- or antiangiogenic factors, and an imbalance in this control chain may result in pathological conditions. Metals as copper, zinc and iron cover an essential role in regulating angiogenesis, thus therapies having physiological metals as target have been proposed. In addition, some complexes of heavier metal ions (e.g., Pt, Au, Ru) are currently used as established or experimental anticancer agents targeting genomic or non-genomic targets. These molecules may affect the angiogenic mechanisms determining different effects that have been only poorly and non-systematically investigated so far. Accordingly, in this review article, we aim to recapitulate the impact on the angiogenic process of some reference anticancer drugs, and how it is connected to the overall pharmacological effects. In addition, we highlight how the activity of these drugs can be related to the role of biological essential metal ions. Overall, this may allow a deeper description and understanding of the antineoplastic activity of both approved or experimental metal complexes, providing important insights for the synthesis of new inorganic drugs able to overcome resistance and recurrence phenomena.

Oncologic feasibility for negative pressure wound therapy application in surgical wounds: A meta-analysis

Negative pressure wound therapy (NPWT) decreases postoperative complications of various surgeries. However, the use of NPWT for oncological surgical wounds remains controversial. To evaluate the association of NPWT with oncologic recurrence in surgical wounds without residual malignancy, we analysed studies that compared NPWT with conventional non‐pressure dressings for cancer surgical wounds without residual tumour by August 12, 2020. We compared tumour recurrence rates and postoperative complications between the two procedures. The six studies included 118 patients who received NPWT, and 149 patients who received conventional non‐pressure wound care. The overall quality of the included studies was high based on the Newcastle–Ottawa scale score of 7.5. Tumour recurrence after NPWT was not significantly different compared with conventional non‐negative pressure wound care (9.3% versus 11.4%, P = 0.40). There was no significant heterogeneity between the studies (I² = 3%). Although NTWT was associated with a lower complication rate compared with the control group, the result was non‐significant (P = 0.15). Application of NPWT in oncologic resection wounds without residual malignancy revealed no difference in local recurrence and may reduce the risk of postoperative complications compared with conventional non‐negative pressure dressings. NPWT can be considered an alternative method for reconstruction in challenging cases.

SHED aggregate exosomes shuttled miR-26a promote angiogenesis in pulp regeneration via TGF-β/SMAD2/3 signalling

OBJECTIVES

Pulp regeneration brings big challenges for clinicians, and vascularization is considered as its determining factor. We previously accomplished pulp regeneration with autologous stem cells from deciduous teeth (SHED) aggregates implantation in teenager patients, however, the underlying mechanism needs to be clarified for regenerating pulp in adults. Serving as an important effector of mesenchymal stem cells (MSCs), exosomes have been reported to promote angiogenesis and tissue regeneration effectively. Here, we aimed to investigate the role of SHED aggregate-derived exosomes (SA-Exo) in the angiogenesis of pulp regeneration.

MATERIALS AND METHODS

We extracted exosomes from SHED aggregates and utilized them in the pulp regeneration animal model. The pro-angiogenetic effects of SA-Exo on SHED and human umbilical vein endothelial cells (HUVECs) were evaluated. The related mechanisms were further investigated.

RESULTS

We firstly found that SA-Exo significantly improved pulp tissue regeneration and angiogenesis in vivo. Next, we found that SA-Exo promoted SHED endothelial differentiation and enhanced the angiogenic ability of HUVECs, as indicated by the in vitro tube formation assay. Mechanistically, miR-26a, which is enriched in SA-Exo, improved angiogenesis both in SHED and HUVECs via regulating TGF-β/SMAD2/3 signalling.

CONCLUSIONS

In summary, these data reveal that SA-Exo shuttled miR-26a promotes angiogenesis via TGF-β/SMAD2/3 signalling contributing to SHED aggregate-based pulp tissue regeneration. These novel insights into SA-Exo may facilitate the development of new strategies for pulp regeneration.

Geniposide alleviates choroidal neovascularization by downregulating HB-EGF release from RPE cells by downregulating the miR-145-5p/NF-κB axis

Age-related macular degeneration (AMD), mainly wet AMD, is the major reason for nonreversible vision loss worldwide. Choroidal neovascularization (CNV) is a characteristic pathological manifestation of wet AMD. Stress or injury to the retinal pigment epithelium (RPE) induces proangiogenic factors that drive CNV. An iridoid glycoside extracted from the fruit of gardenia, geniposide (GEN) plays an antiangiogenic role. In this study, GEN inhibited the transcription and expression of heparin-binding epidermal growth factor (HB-EGF), a proangiogenic factor, in hypoxic RPE cells and a mouse laser-induced CNV model. Inhibition of glucagon-like peptide-1 receptor (GLP-1R), a GEN receptor blocker, eliminated the protective effect of GEN. Additionally, GEN decreased the transcription and expression of HB-EGF in hypoxia-exposed RPE cells by downregulating the miR-145-5p/NF-κB axis. Therefore, our research provides a promising novel strategy for wet AMD therapy.

Revascularization After Traumatic Spinal Cord Injury

Traumatic spinal cord injury (SCI) is a complex pathological process. The initial mechanical damage is followed by a progressive secondary injury cascade. The injury ruptures the local microvasculature and disturbs blood-spinal cord barriers, exacerbating inflammation and tissue damage. Although endogenous angiogenesis is triggered, the new vessels are insufficient and often fail to function normally. Numerous blood vessel interventions, such as proangiogenic factor administration, gene modulation, cell transplantation, biomaterial implantation, and physical stimulation, have been applied as SCI treatments. Here, we briefly describe alterations and effects of the vascular system on local microenvironments after SCI. Therapies targeted at revascularization for SCI are also summarized.

Umbilical Mesenchymal Stem Cell-Derived Exosome-Encapsulated Hydrogels Accelerate Bone Repair by Enhancing Angiogenesis

Repair of large bone defects represents a major challenge for orthopedic surgeons. The newly formed microvessels inside grafts play a crucial role in successful bone tissue engineering. Previously, an active role for mesenchymal stem cell (MSC)-derived exosomes in blood vessel development and progression was suggested in the repair of multiple tissues. However, the reports on the application of MSC-derived exosomes in the repair of large bone defects are sparse. In this study, we encapsulated umbilical MSC-derived exosomes (^uMSCEXOs) in hyaluronic acid hydrogel (HA-Gel) and combined them with customized nanohydroxyapatite/poly-ε-caprolactone (nHP) scaffolds to repair cranial defects in rats. Imaging and histological evaluation indicated that the ^uMSCEXOs/Gel/nHP composites markedly enhanced bone regeneration in vivo, and the ^uMSCEXOs might play a key role in this process. Moreover, the in vitro results demonstrated that ^uMSCEXOs promoted the proliferation, migration, and angiogenic differentiation of endothelial progenitor cells (EPCs) but did not significantly affect the osteogenic differentiation of BMSCs. Importantly, mechanistic studies revealed that exosomal miR-21 was the potential intercellular messenger that promoted angiogenesis by upregulating the NOTCH1/DLL4 pathway. In conclusion, our findings exhibit a promising exosome-based strategy in repairing large bone defects through enhanced angiogenesis, which potentially regulated by the miR-21/NOTCH1/DLL4 signaling axis.

Exosomes derived from plasma: promising immunomodulatory agents for promoting angiogenesis to treat radiation-induced vascular dysfunction

Ionizing radiation (IR)-induced vascular disorders slow down tissue regeneration. Exosomes derived from plasma exhibit potential to promote angiogenesis; meanwhile, the immune microenvironment plays a significant role in the process. This study aimed to test the hypothesis that plasma exosomes promote angiogenesis in irradiated tissue by mediating the immune microenvironment. First, we explored the impact of IR on macrophages. We found that cell viability and capacity for promoting angiogenesis were decreased in irradiated macrophages compared to control macrophages. Then, we isolated and characterized rat plasma-derived exosomes (RP-Exos) which were defined as 40-160 nm extracellular vesicles extracted from rat plasma. Afterward, we evaluated the effects of RP-Exos on the behaviors of irradiated macrophages. Our results show that RP-Exos promoted cell proliferation. More importantly, we found that RP-Exos stimulated the immune microenvironment in a manner that improved the angiogenesis-related genes and proteins of irradiated macrophages. The supernatant of macrophage cell cultures was used as conditioned medium to treat human primary umbilical vein endothelial cells, further confirming the pro-angiogenic ability of macrophages receiving RP-Exo intervention. RP-Exos were used in vivo to treat irradiated skin or calvarial defects in irradiated Sprague-Dawley male rats. The results indicated the ability of RP-Exos to enhance angiogenesis and promote tissue regeneration. Our research suggested the potential of plasma exosomes to be used as immunomodulatory agents with angiogenic capacity to treat radiation-associated vascular disorders and facilitate tissue repair.

Cellular Senescence Affects Cardiac Regeneration and Repair in Ischemic Heart Disease

Ischemic heart disease (IHD) is defined as a syndrome of ischemic cardiomyopathy. Myogenesis and angiogenesis in the ischemic myocardium are important for cardiomyocyte (CM) survival, improving cardiac function and decreasing the progression of heart failure after IHD. Cellular senescence is a state of permanent irreversible cell cycle arrest caused by stress that results in a decline in cellular functions, such as proliferation, migration, homing, and differentiation. In addition, senescent cells produce the senescence-associated secretory phenotype (SASP), which affects the tissue microenvironment and surrounding cells by secreting proinflammatory cytokines, chemokines, growth factors, and extracellular matrix degradation proteins. The accumulation of cardiovascular-related senescent cells, including vascular endothelial cells (VECs), vascular smooth muscle cells (VSMCs), CMs and progenitor cells, is an important risk factor of cardiovascular diseases, such as vascular aging, atherosclerotic plaque formation, myocardial infarction (MI) and ventricular remodeling. This review summarizes the processes of angiogenesis, myogenesis and cellular senescence after IHD. In addition, this review focuses on the relationship between cellular senescence and cardiovascular disease and the mechanism of cellular senescence. Finally, we discuss a potential therapeutic strategy for MI targeting senescent cells.

Hydrogel-mediated delivery of microRNA-92a inhibitor polyplex nanoparticles induces localized angiogenesis

Localized stimulation of angiogenesis is an attractive strategy to improve the repair of ischemic or injured tissues. Several microRNAs (miRNAs) such as miRNA-92a (miR-92a) have been reported to negatively regulate angiogenesis in ischemic disease. To exploit the clinical potential of miR-92a inhibitors, safe and efficient delivery needs to be established. Here, we used deoxycholic acid-modified polyethylenimine polymeric conjugates (PEI-DA) to deliver a locked nucleic acid (LNA)-based miR-92a inhibitor (LNA-92a) in vitro and in vivo. The positively charged PEI-DA conjugates condense the negatively charged inhibitors into nano-sized polyplexes (135 ± 7.2 nm) with a positive net charge (34.2 ± 10.6 mV). Similar to the 25 kDa-branched PEI (bPEI₂₅) and Lipofectamine RNAiMAX, human umbilical vein endothelial cells (HUVECs) significantly internalized PEI-DA/LNA-92a polyplexes without any obvious cytotoxicity. Down-regulation of miR-92a following the polyplex-mediated delivery of LNA-92a led to a substantial increase in the integrin subunit alpha 5 (ITGA5), the sirtuin-1 (SIRT1) and Krüppel-like factors (KLF) KLF2/4 expression, formation of capillary-like structures by HUVECs, and migration rate of HUVECs in vitro. Furthermore, PEI-DA/LNA-92a resulted in significantly enhanced capillary density in a chicken chorioallantoic membrane (CAM) model. Localized angiogenesis was substantially induced in the subcutaneous tissues of mice by sustained release of PEI-DA/LNA-92a polyplexes from an in situ forming, biodegradable hydrogel based on clickable poly(ethylene glycol) (PEG) macromers. Our results indicate that PEI-DA conjugates efficiently deliver LNA-92a to improve angiogenesis. Localized delivery of RNA interference (RNAi)-based therapeutics via hydrogel-laden PEI-DA polyplex nanoparticles appears to be a safe and effective approach for different therapeutic targets.

Current Status of Angiogenic Cell Therapy and Related Strategies Applied in Critical Limb Ischemia

Critical limb ischemia (CLI) constitutes the most severe form of peripheral arterial disease (PAD), it is characterized by progressive blockade of arterial vessels, commonly correlated to atherosclerosis. Currently, revascularization strategies (bypass grafting, angioplasty) remain the first option for CLI patients, although less than 45% of them are eligible for surgical intervention mainly due to associated comorbidities. Moreover, patients usually require amputation in the short-term. Angiogenic cell therapy has arisen as a promising alternative for these "no-option" patients, with many studies demonstrating the potential of stem cells to enhance revascularization by promoting vessel formation and blood flow recovery in ischemic tissues. Herein, we provide an overview of studies focused on the use of angiogenic cell therapies in CLI in the last years, from approaches testing different cell types in animal/pre-clinical models of CLI, to the clinical trials currently under evaluation. Furthermore, recent alternatives related to stem cell therapies such as the use of secretomes, exosomes, or even microRNA, will be also described.

Tumor-derived exosomal miRNA-141 promote angiogenesis and malignant progression of lung cancer by targeting growth arrest-specific homeobox gene (GAX)

Previous researches have suggested that exosomal miRNA-141 has association with metastatic lung cancer, however, its role and regulatory mechanism require further study. In this study, exosomes were isolated from lung cancer patients and normal human serum and identified. We found that the expression of miRNA-141 was up-regulated in the lung cancer serum exosomes compared with the normal serum exosomes. When the exosomes were extracted for co-culture with HUVECs, they were absorbed and distributed around the nucleus by confocal microscopy. Moreover, exosomal miRNA-141 from A549 significantly not only promoted the migration and invasion of A549 but also increased the cell proliferation, tube formation of HUVECs. In order to reveal the mechanism of exosomal miRNA-141, bioinformatics analysis revealed that miRNA-141 targeted the binding of Growth arrest-specific homeobox gene (GAX) in the 3'UTR region, and confirmed by MS2-RIP assay and dual-luciferase assay. Exosome miRNA-141 could down-regulate the expression of GAX. Taken together, our results demonstrate that tumor-derived exosomal miRNA-141 promote angiogenesis and malignant progression of lung cancer by targeting GAX. It provides a new possibility for the treatment of lung cancer.

miR-3574 ameliorates intermittent hypoxia-induced cardiomyocyte injury through inhibiting Axin1

Objective: miRNAs play critical roles in the regulation of many cardiovascular diseases. However, its role and potential mechanism in cardiac injury caused by obstructive sleep apnea (OSA) remain poorly elucidated. In the present study, we aimed to investigate the effects of miR-3574 on cardiomyocyte injury under intermittent hypoxia (IH).

Results: We confirmed that IH inhibited cell viability, induced cell apoptosis and suppressed miR-3574 expression in the H9c2. miR-3574 overexpression could ameliorate the effects of IH on the cell viability and cell apoptosis in the H9c2. Axin1 was a target gene of miR-3574, and miR-3574 overexpression reduced the expression of Axin1. miR-3574 could inhibit the IH-induced cardiomyocyte injury via downregulating Axin1. However, Axin1 could partially reverse these effects of miR-3574.

Conclusion: Our study first reveals that miR-3574 could alleviate IH-induced cardiomyocyte injury by targeting Axin1, which may function as a novel and promising therapy target for OSA-associated cardiovascular diseases.

Methods: H9c2 were exposed to IH condition. CCK-8 assay was applied to determine cell viability of H9c2. qRT-PCR was conducted to measure the expression level of mRNA and miRNA. Western blot assay was then performed to detect the protein levels. Finally, we used dual-luciferase reporter assay identify the potential target of miR-3574.

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.