Decreased miR‑92a‑3p expression potentially mediates the pro‑angiogenic effects of oxidative stress‑activated endothelial cell‑derived exosomes by targeting tissue factor

The Role of Tissue Factor In Signaling Pathways of Pathological Conditions and Angiogenesis

Tissue factor (TF) is an integral transmembrane protein associated with the extrinsic coagulation pathway. TF gene expression is regulated in response to inflammatory cytokines, bacterial lipopolysaccharides, and mechanical injuries. TF activity may be affected by phosphorylation of its cytoplasmic domain and alternative splicing. TF acts as the primary initiator of physiological hemostasis, which prevents local bleeding at the injury site. However, aberrant expression of TF, accompanied by the severity of diseases and infections under various pathological conditions, triggers multiple signaling pathways that support thrombosis, angiogenesis, inflammation, and metastasis. Protease-activated receptors (PARs) are central in the downstream signaling pathways of TF. In this study, we have reviewed the TF signaling pathways in different pathological conditions, such as wound injury, asthma, cardiovascular diseases (CVDs), viral infections, cancer and pathological angiogenesis. Angiogenic activities of TF are critical in the repair of wound injuries and aggressive behavior of tumors, which are mainly performed by the actions of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1 (HIF1-α). Pro-inflammatory effects of TF have been reported in asthma, CVDs and viral infections, including COVID-19, which result in tissue hypertrophy, inflammation, and thrombosis. TF-FVII induces angiogenesis via clotting-dependent and -independent mechanisms. Clottingdependent angiogenesis is induced via the generation of thrombin and cross-linked fibrin network, which facilitate vessel infiltration and also act as a reservoir for endothelial cells (ECs) growth factors. Expression of TF in tumor cells and ECs triggers clotting-independent angiogenesis through induction of VEGF, urokinase-type plasminogen activator (uPAR), early growth response 1 (EGR1), IL8, and cysteine-rich angiogenic inducer 61 (Cyr61).

Uncovering the Heterogeneity of Cardiac Lin-KIT+ Cells: A scRNA-seq Study on the Identification of Subpopulations

The reparative potential of cardiac Lin-KIT+ (KIT) cells is influenced by their population, but identifying their markers is challenging due to changes in phenotype during in vitro culture. Resolving this issue requires uncovering cell heterogeneity and discovering new subpopulations. Single-cell RNA sequencing (scRNA-seq) can identify KIT cell subpopulations, their markers, and signaling pathways. We used 10× genomic scRNA-seq to analyze cardiac-derived cells from adult mice and found 3 primary KIT cell populations: KIT1, characterized by high-KIT expression (KITHI), represents a population of cardiac endothelial cells; KIT2, which has low-KIT expression (KITLO), expresses transcription factors such as KLF4, MYC, and GATA6, as well as genes involved in the regulation of angiogenic cytokines; KIT3, with moderate KIT expression (KITMOD), expresses the cardiac transcription factor MEF2C and mesenchymal cell markers such as ENG. Cell-cell communication network analysis predicted the presence of the 3 KIT clusters as signal senders and receivers, including VEGF, CXCL, and BMP signaling. Metabolic analysis showed that KIT1 has the low activity of glycolysis and oxidative phosphorylation (OXPHOS), KIT2 has high glycolytic activity, and KIT3 has high OXPHOS and fatty acid degradation activity, indicating distinct metabolic adaptations of the 3 KIT populations. Through the systemic infusion of KIT1 cells in a mouse model of myocardial infarction, we observed their involvement in promoting the formation of new micro-vessels. In addition, in vitro spheroid culture experiments demonstrated the cardiac differentiation capacity of KIT2 cells.

Cysticercus pisiformis-derived novel-miR1 targets TLR2 to inhibit the immune response in rabbits

Cysticercosis pisiformis, a highly prevalent parasitic disease worldwide, causes significant economic losses in the rabbit breeding industry. Previous investigations have identified a novel microRNA, designated as novel-miR1, within the serum of rabbit infected with Cysticercus pisiformis. In the present study, we found that C. pisiformis-derived novel-miR1 was released into the rabbit serum via exosomes. Through computational analysis using TargetScan, miRanda, and PITA, a total of 634 target genes of novel-miR1 were predicted. To elucidate the functional role of novel-miR1, a dual-luciferase reporter assay was utilized and demonstrated that novel-miR1 targets rabbit Toll-like receptor 2 (TLR2). Rabbit peripheral blood lymphocytes (PBLCs) were transfected with novel-miR1 mimic and mimic NC, and the in vitro experiments confirmed that novel-miR1 suppressed the expression of pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6 through the nuclear factor kappa B (NF-κB) pathway. In vivo experiments demonstrated that novel-miR1 was significantly upregulated during the 1-3 months following infection with C. pisiformis in rabbits. Notably, this upregulation coincided with a downregulation of TLR2, P65, pP65, TNF-α, IL-1β, and IL-6 in PBLCs. Collectively, these results indicate that the novel-miR1 derived from C. pisiformis inhibited the rabbits' immune response by suppressing the NF-κB-mediated immune response. This immune modulation facilitates parasite invasion, survival, and establishment of a persistent infection.

Deficiency of miR-409-3p improves myocardial neovascularization and function through modulation of DNAJB9/p38 MAPK signaling

Angiogenesis is critical for tissue repair following myocardial infarction (MI), which is exacerbated under insulin resistance or diabetes. MicroRNAs are regulators of angiogenesis. We examined the metabolic regulation of miR-409-3p in post-infarct angiogenesis. miR-409-3p was increased in patients with acute coronary syndrome (ACS) and in a mouse model of acute MI. In endothelial cells (ECs), miR-409-3p was induced by palmitate, while vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) decreased its expression. Overexpression of miR-409-3p decreased EC proliferation and migration in the presence of palmitate, whereas inhibition had the opposite effects. RNA sequencing (RNA-seq) profiling in ECs identified DNAJ homolog subfamily B member 9 (DNAJB9) as a target of miR-409-3p. Overexpression of miR-409-3p decreased DNAJB9 mRNA and protein expression by 47% and 31% respectively, while enriching DNAJB9 mRNA by 1.9-fold after Argonaute2 microribonucleoprotein immunoprecipitation. These effects were mediated through p38 mitogen-activated protein kinase (MAPK). Ischemia-reperfusion (I/R) injury in EC-specific miR-409-3p knockout (KO) mice (miR-409ECKO) fed a high-fat, high-sucrose diet increased isolectin B4 (53.3%), CD31 (56%), and DNAJB9 (41.5%). The left ventricular ejection fraction (EF) was improved by 28%, and the infarct area was decreased by 33.8% in miR-409ECKO compared with control mice. These findings support an important role of miR-409-3p in the angiogenic EC response to myocardial ischemia.

Role of Circulating Exosomes in Cerebrovascular Diseases: A Comprehensive Review

Exosomes are lipid bilayer vesicles that contain multiple macromolecules secreted by the parent cells and play a vital role in intercellular communication. In recent years, the function of exosomes in cerebrovascular diseases (CVDs) has been intensively studied. Herein, we briefly review the current understanding of exosomes in CVDs. We discuss their role in the pathophysiology of the diseases and the value of the exosomes for clinical applications as biomarkers and potential therapies.

Exosomes: mediators regulating the phenotypic transition of vascular smooth muscle cells in atherosclerosis

Cardiovascular disease is one of the leading causes of human mortality worldwide, mainly due to atherosclerosis (AS), and the phenotypic transition of vascular smooth muscle cells (VSMCs) is a key event in the development of AS. Exosomes contain a variety of specific nucleic acids and proteins that mediate intercellular communication. The role of exosomes in AS has attracted attention. This review uses the VSMC phenotypic transition in AS as the entry point, introduces the effect of exosomes on AS from different perspectives, and discusses the status quo, deficiencies, and potential future directions in this field to provide new ideas for clinical research and treatment of AS. Video Abstract.

Long noncoding RNA TUG1 induces angiogenesis of endothelial progenitor cells and dissolution of deep vein thrombosis

Objective

Long non-coding RNA (lncRNA) essentially controls many physiological and pathological processes of deep vein thrombosis (DVT). Based on that, lncRNA taurine upregulated gene 1 (TUG1)-involved angiogenesis of endothelial progenitor cells (EPCs) and dissolution of DVT was explored.

Methods

In the in-vitro experiments, EPCs were engineered with mimic, inhibitor, siRNA, and plasmid, after which tube formation, proliferation, migration, and apoptosis were checked. In the in-vivo experiments, a DVT mouse model was established. Before the DVT operation, the mice were injected with agomir, antagomir, siRNA, and plasmid. Subsequently, thrombosis and damage to the femoral vein were pathologically evaluated. TUG1, miR-92a-3p, and 3-Hydroxy-3-methylglutaryl coenzyme A reductase (Hmgcr) expression in the femoral vein was tested. The relationship between TUG1, miR-92a-3p, and Hmgcr was validated.

Results

DVT mice showed suppressed TUG1 and Hmgcr expression, and elevated miR-92a-3p expression. In EPCs, TUG1 overexpression or miR-92a-3p inhibition promoted cellular angiogenesis, whereas Hmgcr silencing blocked cellular angiogenesis. In DVT mice, elevated TUG1 or inhibited miR-92a-3p suppressed thrombosis and damage to the femoral vein whilst Hmgcr knockdown acted oppositely. In both cellular and animal models, TUG1 overexpression-induced effects could be mitigated by miR-92a-3p up-regulation. Mechanically, TUG1 interacted with miR-92a-3p to regulate Hmgcr expression.

Conclusion

Evidently, TUG1 promotes the angiogenesis of EPCs and dissolution of DVT via the interplay with miR-92a-3p and Hmgcr.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00413-y.

Characteristics of culture-condition stimulated exosomes or their loaded hydrogels in comparison with other extracellular vesicles or MSC lysates

Recently, it has become popular to study the use of extracellular vesicles (EVs) secreted by stem cells to repair damaged tissues or lost cells. Various cell types and physiological fluids release EVs, and they play an important role in cell-to-cell communication. Moreover, EVs have been implicated in important processes, such as immune responses, homeostasis maintenance, coagulation, inflammation, cancer progression, angiogenesis, and antigen presentation. Thus, EVs participate in both physiological and pathological progression. The main classes of EVs include exosomes, microvesicles (MVs), and apoptotic bodies (ApoBDs). Exosomes, which carry a mass of signal molecules such as RNA, DNA, proteins, and lipids, are the most important of these EVs subsets. Currently, exosomes are generating substantial interest in the scientific community. Exosomes loaded hydrogels or under different cultural environments exhibit different properties and functions. Therefore, the exosomes obtained from different sources and conditions are worth reviewing. More importantly, no review article has compared the different EVs, such as exosomes, MVs, ApoBDs, and mesenchymal stem cell (MSC) lysates, which are special soluble substances. The differentiation between EVs and MSC lysates is a logical approach. Accordingly, this review provides an update on the latest progress in studying the roles of culture-condition stimulated exosomes or their loaded hydrogels and the differentiation between exosomes, MVs, ApoBDs, and MSC lysates. Published studies were retrieved from the PubMed® database for review.

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.