LncRNA WTAPP1 Promotes Migration and Angiogenesis of Endothelial Progenitor Cells via MMP1 Through MicroRNA 3120 and Akt/PI3K/Autophagy Pathways

Harnessing pseudogenes for lung cancer: A novel epigenetic target in diagnosis, prognosis and treatment

Pseudogenes are abundantly present in the human genome and are often thought of as nonfunctional nucleotide sequences, but a growing body of research suggests that pseudogenes can play important biological roles through a variety of pathways, and can be involved in the development of cancer. Lung cancer is one of the most prevalent cancers in the world and it is crucial to find new therapeutic strategies for the treatment of lung cancer. In recent years, studies on the effects of pseudogenes on lung carcinogenesis have increased rapidly. This has pointed to new directions in the diagnosis and treatment of lung cancer. Aim of this paper is to comprehensively discuss the role and influence of pseudogenes in the lung cancer, and the potential of pseudogenes as novel epigenetic targets in lung cancer diagnosis and prognosis and treatment, which is significant for realizing the clinical benefits of pseudogenes.

LncRNA AGAP2-AS1 stabilizes ATG9A to promote autophagy in endothelial cells - Implications for burn wound healing

Deep second- or mixed-degree burn lesions are difficult to heal due to the impaired dermis supporting of epidermis renewal and nutrition delivery. Early dermis debridement and preservation speed healing and enhance results, emphasizing the need of knowing processes that promote burn-denatured dermis recovery, notably endothelial cell angiogenesis and autophagy. Integrative bioinformatics investigations identified AGAP2-AS1 as a highly elevated lncRNA in burn tissues. Pearson's correlation study connected AGAP2-AS1 to 112 differently co-expressed protein-coding genes involved in burn healing processes such cell cycle and TGF-beta receptor signaling. Experimental validation showed that heat damage elevated AGAP2-AS1 in HUVECs and HDMECs. Functionally, AGAP2-AS1 overexpression in heat-denatured HUVECs and HDMECs increased cell survival, migration, invasion, and angiogenesis. In addition, AGAP2-AS1 overexpression increased endothelial cell autophagy. Additional investigation showed AGAP2-AS1's association with ATG9A, stabilizing it. Post-heat damage, ATG9A knockdown drastically reduced HUVEC and HDMEC survival, migration, invasion, angiogenesis, and autophagy. More notably, ATG9A knockdown drastically reduced the benefits of AGAP2-AS1 overexpression on endothelial cell functions and autophagy. The positive association between AGAP2-AS1 and ATG9A expression in burn tissue samples highlights their crucial roles in endothelial cell response to heat injury, indicating that targeting this axis may aid burn wound healing. The research found that lncRNA AGAP2-AS1 stabilizes ATG9A and promotes autophagy in endothelial cells. These results imply that targeting the AGAP2-AS1/ATG9A axis may improve angiogenesis and tissue regeneration in burn injuries, revealing burn wound healing molecular pathways.

The Role and Potential Mechanisms of Rehabilitation Exercise Improving Cardiac Remodeling

Rehabilitation exercise is a crucial non-pharmacological intervention for the secondary prevention and treatment of cardiovascular diseases, effectively ameliorating cardiac remodeling in patients. Exercise training can mitigate cardiomyocyte apoptosis, reduce extracellular matrix deposition and fibrosis, promote angiogenesis, and regulate inflammatory response to improve cardiac remodeling. This article presents a comprehensive review of recent research progress, summarizing the pivotal role and underlying mechanism of rehabilitation exercise in improving cardiac remodeling and providing valuable insights for devising effective rehabilitation treatment programs. Graphical Abstract.

The emerging roles of miRNA-mediated autophagy in ovarian cancer

Ovarian cancer is one of the common tumors of the female reproductive organs. It has a high mortality rate, is highly heterogeneous, and early detection and primary prevention are very complex. Autophagy is a cellular process in which cytoplasmic substrates are targeted for degradation in lysosomes through membrane structures called autophagosomes. The periodic elimination of damaged, aged, and redundant cellular molecules or organelles through the sequential translation between amino acids and proteins by two biological processes, protein synthesis, and autophagic protein degradation, helps maintain cellular homeostasis. A growing number of studies have found that autophagy plays a key regulatory role in ovarian cancer. Interestingly, microRNAs regulate gene expression at the posttranscriptional level and thus can regulate the development and progression of ovarian cancer through the regulation of autophagy in ovarian cancer. Certain miRNAs have recently emerged as important regulators of autophagy-related gene expression in cancer cells. Moreover, miRNA analysis studies have now identified a sea of aberrantly expressed miRNAs in ovarian cancer tissues that can affect autophagy in ovarian cancer cells. In addition, miRNAs in plasma and stromal cells in tumor patients can affect the expression of autophagy-related genes and can be used as biomarkers of ovarian cancer progression. This review focuses on the potential significance of miRNA-regulated autophagy in the diagnosis and treatment of ovarian cancer.

Extracellular Vesicles' Role in Angiogenesis and Altering Angiogenic Signaling

Angiogenesis, the process of new blood vessels formation from existing vasculature, plays a vital role in development, wound healing, and various pathophysiological conditions. In recent years, extracellular vesicles (EVs) have emerged as crucial mediators in intercellular communication and have gained significant attention for their role in modulating angiogenic processes. This review explores the multifaceted role of EVs in angiogenesis and their capacity to modulate angiogenic signaling pathways. Through comprehensive analysis of a vast body of literature, this review highlights the potential of utilizing EVs as therapeutic tools to modulate angiogenesis for both physiological and pathological purposes. A good understanding of these concepts holds promise for the development of novel therapeutic interventions targeting angiogenesis-related disorders.

Non-coding RNAs regulating endothelial progenitor cells for venous thrombosis: promising therapy and innovation

Venous thromboembolism, which includes deep venous thrombosis (DVT) and pulmonary embolism, is the third most common vascular disease in the world and seriously threatens the lives of patients. Currently, the effect of conventional treatments on DVT is limited. Endothelial progenitor cells (EPCs) play an important role in the resolution and recanalization of DVT, but an unfavorable microenvironment reduces EPC function. Non-coding RNAs, especially long non-coding RNAs and microRNAs, play a crucial role in improving the biological function of EPCs. Non-coding RNAs have become clinical biomarkers of diseases and are expected to serve as new targets for disease intervention. A theoretical and experimental basis for the development of new methods for preventing and treating DVT in the clinic will be provided by studies on the role and molecular mechanism of non-coding RNAs regulating EPC function in the occurrence and development of DVT. To summarize, the characteristics of venous thrombosis, the regulatory role of EPCs in venous thrombosis, and the effect of non-coding RNAs regulating EPCs on venous thrombosis are reviewed. This summary serves as a useful reference and theoretical basis for research into the diagnosis, prevention, treatment, and prognosis of venous thrombosis.

Evaluation of long noncoding RNA (LncRNA) in pathogenesis of HELLP syndrome: diagnostic and future approach

HELLP syndrome is a disorder during pregnancy which is defined by elevation of liver enzymes, haemolysis, and low platelet count. This syndrome is a multifactorial one and both genetic and environmental components can have a crucial role in this syndrome's pathogenesis. Long noncoding RNAs (lncRNAs), are defined as long non-protein coding molecules (more than 200 nucleotides), which are functional units in most cellular processes such as cell cycle, differentiation, metabolism and some diseases progression. As these markers discovered, there has been some evidence that they have an important role in the function of some organs, such as placenta; therefore, alteration and dysregulation of these RNAs can develop or alleviate HELLP disorder. Although the role of lncRNAs has been shown in HELLP syndrome, the process is still unclear. In this review, our purpose is to evaluate the association between molecular mechanisms of lncRNAs and HELLP syndrome pathogenicity to elicit some novel approaches for HELLP diagnosis and treatment.

Sonic hedgehog signaling promotes angiogenesis of endothelial progenitor cells to improve pressure ulcers healing by PI3K/AKT/eNOS signaling

BACKGROUND

Pressure ulcer is a severe disease in the paralyzed and aging populations. Endothelial progenitor cells (EPCs) are able to regulate ulcer healing by modulating angiogenesis, but the molecular mechanism is still obscure. Sonic hedgehog (SHH) signaling contributes to angiogenesis in various diseases and has been identified to modulate EPCs function. Here, we aimed to explore the significance of SHH signaling in EPCs function during pressure ulcers.

METHODS

The EPCs were isolated and characterized by the expression of DiI-acLDL and bind fluorescein iso-thiocyanate UEA-1. Cell proliferation was detected by cell counting kit 8 (CCK-8). The DiI-acLDL and bind fluorescein iso-thiocyanate UEA-1 were analyzed by immunofluorescent analysis. The angiogenesis of EPCs was analyzed by tube formation assay. The pressure ulcers rat model was constructed, the wound injury was analyzed by H&E staining and angiogenesis was analyzed by the accumulation of CD31 based on immunofluorescent analysis.

RESULTS

The expression of patched-1 and Gli-1 was enhanced by SHH activator SAG but reduced by SHH inhibitor cyclopamine in the EPCsThe PI3K, Akt, eNOS expression and the Akt phosphorylation were induced by SAG, while the treatment of cyclopamine presented a reversed result. The proliferation and migration of EPCs were enhanced by SAG but repressed by cyclopamine or PI3K/AKT/eNOS signaling inhibitor Y294002, in which the co-treatment of Y294002 could reverse the effect of SAG.

CONCLUSIONS

Thus, we found that SHH signaling activated angiogenesis properties of EPCs to improve pressure ulcers healing by PI3K/AKT/eNOS signaling. SHH signaling may serve as the potential target for attenuating pressure ulcers.

Emerging role of exosome-derived non-coding RNAs in tumor-associated angiogenesis of tumor microenvironment

The tumor microenvironment (TME) is an intricate ecosystem that is actively involved in various stages of cancer occurrence and development. Some characteristics of tumor biological behavior, such as proliferation, migration, invasion, inhibition of apoptosis, immune escape, angiogenesis, and metabolic reprogramming, are affected by TME. Studies have shown that non-coding RNAs, especially long-chain non-coding RNAs and microRNAs in cancer-derived exosomes, facilitate intercellular communication as a mechanism for regulating angiogenesis. They stimulate tumor growth, as well as angiogenesis, metastasis, and reprogramming of the TME. Exploring the relationship between exogenous non-coding RNAs and tumor-associated endothelial cells, as well as their role in angiogenesis, clinicians will gain new insights into treatment as a result.

Crosstalk between long noncoding RNA and microRNA in Cancer

miRNAs and lncRNAs play a central role in cancer-associated gene regulations. The dysregulated expression of lncRNAs has been reported as a hallmark of cancer progression, acting as an independent prediction marker for an individual cancer patient. The interplay of miRNA and lncRNA decides the variation of tumorigenesis that could be mediated by acting as sponges for endogenous RNAs, regulating miRNA decay, mediating intra-chromosomal interactions, and modulating epigenetic components. This paper focuses on the influence of crosstalk between lncRNA and miRNA on cancer hallmarks such as epithelial-mesenchymal transition, hijacking cell death, metastasis, and invasion. Other cellular roles of crosstalks, such as neovascularization, vascular mimicry, and angiogenesis were also discussed. Additionally, we reviewed crosstalk mechanism with specific host immune responses and targeting interplay (between lncRNA and miRNA) in cancer diagnosis and management.

Dimethyloxalylglycine Attenuates Steroid-Associated Endothelial Progenitor Cell Impairment and Osteonecrosis of the Femoral Head by Regulating the HIF-1α Signaling Pathway

Endothelial impairment and dysfunction are closely related to the pathogenesis of steroid-associated osteonecrosis of the femoral head (SONFH). Recent studies have showed that hypoxia inducible factor-1α (HIF-1α) plays a crucial role in endothelial homeostasis maintenance. Dimethyloxalylglycine (DMOG) could suppress HIF-1 degradation and result in nucleus stabilization by repressing prolyl hydroxylase domain (PHD) enzymatic activity. Our results showed that methylprednisolone (MPS) remarkably undermined biological function of endothelial progenitor cells (EPC) by inhibiting colony formation, migration, angiogenesis, and stimulating senescence of EPCs, while DMOG treatment alleviated these effects by promoting HIF-1α signaling pathway, as evidenced by senescence-associated β-galactosidase (SA-β-Gal) staining, colony-forming unit, matrigel tube formation, and transwell assays. The levels of proteins related to angiogenesis were determined by ELISA and Western blotting. In addition, active HIF-1α bolstered the targeting and homing of endogenous EPCs to the injured endothelium in the femoral head. Histopathologically, our in vivo study showed that DMOG not only alleviated glucocorticoid-induced osteonecrosis but also promoted angiogenesis and osteogenesis in the femoral head as detected by microcomputed tomography (Micro-CT) analysis and histological staining of OCN, TRAP, and Factor Ⅷ. However, all of these effects were impaired by an HIF-1α inhibitor. These findings demonstrate that targeting HIF-1α in EPCs may constitute a novel therapeutic approach for the treatment of SONFH.

LINC00659 exacerbates endothelial progenitor cell dysfunction in deep vein thrombosis of the lower extremities by activating DNMT3A-mediated FGF1 promoter methylation

It has been shown that long non-coding RNA (lncRNA) LINC00659 was markedly upregulated in the peripheral blood of patients with deep venous thrombosis (DVT). However, the function of LINC00659 in lower extremity DVT (LEDVT) remains to be largely unrevealed. A total of 30 inferior vena cava (IVC) tissue samples and peripheral blood (60 ml per subject) were obtained from LEDVT patients (n = 15) and healthy donors (n = 15), and then LINC00659 expression was detected by RT-qPCR. The results displayed that LINC00659 is upregulated in IVC tissues and isolated endothelial group cells (EPCs) of patients with LEDVT. LINC00659 knock-down promoted the proliferation, migration, and angiogenesis ability of EPCs, while an pcDNA-eukaryotic translation initiation factor 4A3 (EIF4A3), a EIF4A3 overexpression vector, or fibroblast growth factor 1 (FGF1) small interfering RNA (siRNA) combined with LINC00659 siRNA could not enhance this effect. Mechanistically, LINC00659 bound with EIF4A3 promoter to upregulated EIF4A3 expression. Besides, EIF4A3 could facilitate FGF1 methylation and its downregulated expression by recruiting DNA methyltransferases 3A (DNMT3A) to the FGF1 promoter region. Additionally, LINC00659 inhibition could alleviate LEDVT in mice. In summary, the data indicated the roles of LINC00659 in the pathogenesis of LEDVT, and the LINC00659/EIF4A3/FGF1 axis could be a novel therapeutic target for the treatment of LEDVT.

Injectable MMP1-sensitive microspheres with spatiotemporally controlled exosome release promote neovascularized bone healing

Bone marrow mesenchymal stromal cell-derived exosomes (BMSC-Exos) can recruit stem cells for bone repair, with neovessels serving as the main migratory channel for stem cells to the injury site. However, existing exosome (Exo) delivery strategies cannot reach the angiogenesis phase following bone injury. To that end, an enzyme-sensitive Exo delivery material that responds to neovessel formation during the angiogenesis phase was designed in the present study to achieve spatiotemporally controlled Exo release. Herein, matrix metalloproteinase-1 (MMP1) was found to be highly expressed in neovascularized bone; as a result, we proposed an injectable MMP1-sensitive hydrogel microspheres (KGE) made using a microfluidic chip prepared by mixing self-assembling peptide (KLDL-MMP1), GelMA, and BMSC-Exos. The results revealed that KGE microspheres had a uniform diameter of 50-70 µm, ideal for minimally invasive injection and could release exosomes in response to MMP1 expression. In vitro experiments demonstrated that KGE had less cytotoxicity and could promote the migration and osteodifferentiation of BMSCs. Furthermore, in vivo experiments confirmed that KGE could promote bone repair during angiogenesis by recruiting CD90⁺ stem cells via neovessels. Collectively, our results suggest that injectable enzyme-responsive KGE microspheres could be a promising Exo-secreting material for accelerating neovascularized bone healing. STATEMENT OF SIGNIFICANCE: Exosomes can spread through blood vessels and activate stem cells to participate in bone repair, but under normal circumstances, exosomes lacking sustained-release delivery materials cannot be maintained until the angiogenesis phase. In this study, we found that MMP1 was highly expressed in neovascularized bone, then we proposed an MMP1-sensitive injectable microsphere that carries exosomes and responds temporally and spatially to neovascularization, which maximizes the ability of exosomes to recruit stem cells. Different from previous strategies that focus on promoting angiogenesis to accelerate bone healing, this is a brand new delivery strategy that is stimuli-responsive to neovessel formation. In addition, the preparation of self-assembled peptide microspheres by a microfluidic chip is also proposed for the first time.

Orexin-A exerts neuroprotective effect in experimental intracerebral hemorrhage by suppressing autophagy via OXR1-mediated ERK/mTOR signaling pathway

Background

Orexin-A (OXA) is a polypeptide produced in the hypothalamus, which binds to specific receptors and exerts multiple physiological effects. Autophagy plays a vital role in early brain injury (EBI) after intracerebral hemorrhage (ICH). However, the relationship between OXA and autophagy after ICH has not been confirmed.

Methods

In this study, the protective role of OXA was investigated in a model of hemin-induced injury in PC12 cells and blood-injection ICH model in rats, and its potential molecular mechanism was clarified. Neurobehavioral tests, brain water content, and pathologic morphology were assessed after ICH. Cell survival rate was determined using Cell Counting Kit-8 (CCK-8), while apoptosis was detected using flow cytometry. The autophagy protein LC3 that was originally identified as microtubule-associated protein 1 light 3 was evaluated by immunohistochemistry. The ultrastructural changes of cells following ICH were observed by transmission electron microscopy. Western blotting was performed to determine the expression levels of LC3, p62/SQSTM1 (p62), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK_1/2), total extracellular signal-regulated kinase 1/2 (t-ERK_1/2), mammalian target of rapamycin (mTOR), and phosphorylated mammalian target of rapamycin (p-mTOR).

Results

OXA treatment significantly improved neurofunctional outcomes, reduced brain edema, and alleviated neuronal apoptosis. OXA administration upregulated p-mTOR and p62, while it downregulated p-ERK_1/2 and LC3; this effect was reversed by the orexin receptor 1 (OXR1) antagonist SB-334867.

Conclusions

This study demonstrates that OXA suppresses autophagy via the OXR1-mediated ERK/mTOR signaling pathway to exert neuroprotective effects, and it might provide a novel therapeutic approach in patients suffering from ICH.

Non-Coding RNAs in Regulating Plaque Progression and Remodeling of Extracellular Matrix in Atherosclerosis

Non-coding RNAs (ncRNAs) regulate cell proliferation, migration, differentiation, inflammation, metabolism of clinically important biomolecules, and other cellular processes. They do not encode proteins but are involved in the regulatory network of various proteins that are directly related to the pathogenesis of diseases. Little is known about the ncRNA-associated mechanisms of atherosclerosis and related cardiovascular disorders. Remodeling of the extracellular matrix (ECM) is critical in the pathogenesis of atherosclerosis and related disorders; however, its regulatory proteins are the potential subjects to explore with special emphasis on epigenetic regulatory components. The activity of regulatory proteins involved in ECM remodeling is regulated by various ncRNA molecules, as evident from recent research. Thus, it is important to critically evaluate the existing literature to enhance the understanding of nc-RNAs-regulated molecular mechanisms regulating ECM components, remodeling, and progression of atherosclerosis. This is crucial since deregulated ECM remodeling contributes to atherosclerosis. Thus, an in-depth understanding of ncRNA-associated ECM remodeling may identify novel targets for the treatment of atherosclerosis and other cardiovascular diseases.

Autophagy promotes directed migration of HUVEC in response to electric fields through the ROS/SIRT1/FOXO1 pathway

Endogenous electric fields (EFs) have been confirmed to facilitate angiogenesis through guiding directional migration of endothelial cells (ECs), but the underlying mechanisms remain obscure. Recent studies suggest that the directed migration of ECs in angiogenesis is correlated with autophagy, and the latter of which could be augmented by EFs. We hypothesize that autophagy may participate in the EFs-guided migration of ECs during angiogenesis. Herein, we showed that EFs induced human umbilical vein endothelial cells (HUVEC) migration toward the cathode with enhanced autophagy. Genetic ablation of autophagy by silencing the autophagy-related gene (Atg) 5 abolished the EFs-directed migration of HUVEC, indicating that autophagy is definitely required for EFs-guided migration of cells. Mechanistically, we identified the intracellular reactive oxygen species (ROS) as a crucial mediator in EFs-triggered autophagy through augmenting the silencing information regulator 2 related enzyme1 (SIRT1)/forkhead box protein O1 (FOXO1) signaling. Either ROS scavenging or SIRT1 knockdown eliminated the EFs-triggered autophagy in HUVEC. Further study showed that SIRT1 promoted FOXO1 deacetylation, facilitating its nuclear accumulation and transcriptional activity, and thereby activating autophagy in EFs-treated HUVECs. In conclusion, our study demonstrated a pivotal role for autophagy in EFs-induced directed migration of HUVECs through the ROS/SIRT1/FOXO1 pathway, and provided a novel theoretical foundation for angiogenesis.

Mechanical Stretch Induced Skin Regeneration: Molecular and Cellular Mechanism in Skin Soft Tissue Expansion

Skin soft tissue expansion is one of the most basic and commonly used techniques in plastic surgery to obtain excess skin for a variety of medical uses. However, skin soft tissue expansion is faced with many problems, such as long treatment process, poor skin quality, high retraction rate, and complications. Therefore, a deeper understanding of the mechanisms of skin soft tissue expansion is needed. The key to skin soft tissue expansion lies in the mechanical stretch applied to the skin by an inflatable expander. Mechanical stimulation activates multiple signaling pathways through cellular adhesion molecules and regulates gene expression profiles in cells. Meanwhile, various types of cells contribute to skin expansion, including keratinocytes, dermal fibroblasts, and mesenchymal stem cells, which are also regulated by mechanical stretch. This article reviews the molecular and cellular mechanisms of skin regeneration induced by mechanical stretch during skin soft tissue expansion.

The Emerging Role of RNA N6-Methyladenosine Modification in Pancreatic Cancer

Pancreatic cancer (PC) is one of the most common malignant cancers, ranking the seventh highest causes of cancer-related deaths globally. Recently, RNA N6-methyladenosine (m6A) is emerging as one of the most abundant RNA modifications in eukaryote cells, involved in multiple RNA processes including RNA translocation, alternative splicing, maturation, stability, and degradation. As reported, m6A was dynamically and reversibly regulated by its “writers”, “erasers”, and “readers”, Increasing evidence has revealed the vital role of m6A modification in the development of multiple types of cancers including PC. Currently, aberrant m6A modification level has been found in both PC tissues and cell lines. Moreover, abnormal expressions of m6A regulators and m6A-modified genes have been reported to contribute to the malignant development of PC. Here in this review, we will focus on the function and molecular mechanism of m6A-modulated RNAs including coding RNAs as well as non-coding RNAs. Then the m6A regulators will be summarized to reveal their potential applications in the clinical diagnosis, prognosis, and therapeutics of PC.

Oxidative stress-induced endothelial cells-derived exosomes accelerate skin flap survival through Lnc NEAT1-mediated promotion of endothelial progenitor cell function

Background

Flap transplantation is commonly used in reconstructive surgery. A prerequisite for skin flap survival is sufficient blood supply. However, such approaches remain unclear. This study aimed to explore the underlying mechanisms of exosomes derived from human umbilical vascular endothelial cells (HUVECs) exposed to oxidative stress on endothelial progenitor cells (EPCs) and their subsequent influence on the survival of skin flaps.

Methods

HUVECs were treated with various concentrations of H₂O₂ to establish an oxidative stress model. To investigate the effects of H₂O₂-HUVEC-Exos and HUVEC-Exos, Cell Counting Kit-8, tube formation, invasion assays, and quantitative real-time polymerase chain reaction (qRT-PCR) were performed in EPCs. Microarray analysis was used to reveal the differentially expressed long non-coding RNAs (lncRNAs) in the H₂O₂-HUVEC-Exos and HUVEC-Exos. In addition, gene silencing and western blotting were employed to determine the mechanism behind lncRNA nuclear enrichment enriched transcript 1 (Lnc NEAT1) in EPCs. Further, a rat skin flap model was used to determine the role of the exosomes in skin flap survival in vivo.

Results

HUVECs were stimulated with 100 μmol/L H₂O₂ for 12 h to establish an oxidative stress model. H₂O₂-HUVEC-Exos promoted the proliferation, tube formation, and invasion of EPCs and remarkably increased skin flap survival compared to the HUVEC-Exos and control groups. Sequencing of exosome RNAs revealed that the Lnc NEAT1 level was dramatically increased in the H₂O₂-HUVEC-Exos, leading to activation of the Wnt/β-catenin signaling pathway. Comparatively, knockdown of Lnc NEAT1 in HUVEC-Exos and H₂O₂-HUVEC-Exos significantly inhibits the angiogenic capacity of EPCs, reduced the survival area of skin flap and downregulated the expression levels of Wnt/β-catenin signaling pathway proteins, whereas Wnt agonist partly reversed the negative effect of NEAT1 downregulation on EPCs through the Wnt/β-catenin signaling pathway.

Conclusions

Exosomes derived from HUVECs stimulated by oxidative stress significantly promoted the pro-angiogenic ability of EPCs through the Wnt/β-catenin signaling pathway mediated by Lnc NEAT1 and hence enhanced random flap survival in vivo. Therefore, the application of H₂O₂-HUVEC-Exos may serve as an alternative therapy for improving random skin flap survival.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03013-9.

PINK1-Dependent Mitophagy Reduced Endothelial Hyperpermeability and Cell Migration Capacity Under Simulated Microgravity

The effect of cardiovascular dysfunction including orthostatic intolerance and disability on physical exercise is one of the health problems induced by long-term spaceflight astronauts face. As an important part of vascular structure, the vascular endothelium, uniquely sensitive to mechanical force, plays a pivotal role in coordinating vascular functions. Our study found that simulated microgravity induced PINK1-dependent mitophagy in human umbilical vein endothelial cells (HUVECs). Here, we explored the underlying mechanism of mitophagy induction. The ER stress induced by proteostasis failure in HUVECs promoted the Ca2+ transfer from ER to mitochondria, resulting in mitochondria Ca2+ overload, decreased mitochondrial membrane potential, mitochondria fission, and accumulation of Parkin and p62 in mitochondria and mitophagy under simulated microgravity. Moreover, we assumed that mitophagy played a vital role in functional changes in endothelial cells under simulated microgravity. Using mdivi-1 and PINK1 knockdown, we found that NLRP3 inflammasome activation was enhanced after mitophagy was inhibited. The NLRP3 inflammasome contributed to endothelial hyperpermeability and cellular migration by releasing IL-1β. Thus, mitophagy inhibited cell migration ability and hyperpermeability in HUVECs exposed to clinostat-simulated microgravity. Collectively, we here clarify the mechanism of mitophagy induction by simulated microgravity in vitro and demonstrate the relationship between mitophagy and vascular endothelial functional changes including cellular migration and permeability. This study deepens the understanding of vascular functional changes under microgravity.

Suppression of long intergenic non-protein coding RNA 1123 constrains lower extremity deep vein thrombosis via microRNA-125a-3p to target interleukin 1 receptor type 1

Lower extremity deep vein thrombosis (LEDVT) is a disorder of venous return caused by abnormal blood clotting. LEDVT can obstruct the lumen and is the third most common vascular disease after cerebrovascular disease and coronary artery disease. LncRNAs are associated with thrombosis and potentially affect the pathogenesis of DVT. However, no studies have reported the effect of LINC01123 on LEDVT. The aim of this study was to investigate the effect of LINC01123 on LEDVT in rats via the miR-125a-3p/interleukin 1 receptor type 1 (IL1R1) axis. Lentiviral vectors that altering LINC01123, miR-125a-3p and IL1R1 expression were pre-injected into the tail vein of rats, and an LEDVT model was established 1 day later. Detection of LINC01123, miR-125a-3p and IL1R1 expression was performed. Inflammatory factors in femoral venous blood, the length and weight of the thrombus, the histomorphological changes were determined in the rat model. The targeting relation of miR-125a-3p with LINC01123 or IL1R1 was verified. The results presented that LEDVT rats expressed high LINC01123 and IL1R1 and low miR-125a-3p expression levels. After silencing LINC01123 or elevating miR-125a-3p, the rate of thrombosis, length and weight of thrombus, and levels of inflammatory factors were reduced. The targeting relation was presented between miR-125a-3p with LINC01123 or IL1R1. Elevating IL1R1 was available to turn around the action of silence of LINC01123 on LEDVT rats. All in all, suppression of LINC01123 restrains LEDVT via miR-125a-3p to target IL1R1.

Regulation of Endothelial Progenitor Cell Functions in Ischemic Heart Disease: New Therapeutic Targets for Cardiac Remodeling and Repair

Ischemic heart disease (IHD) is the leading cause of morbidity and mortality worldwide. Ischemia and hypoxia following myocardial infarction (MI) cause subsequent cardiomyocyte (CM) loss, cardiac remodeling, and heart failure. Endothelial progenitor cells (EPCs) are involved in vasculogenesis, angiogenesis and paracrine effects and thus have important clinical value in alternative processes for repairing damaged hearts. In fact, this study showed that the endogenous repair of EPCs may not be limited to a single cell type. EPC interactions with cardiac cell populations and mesenchymal stem cells (MSCs) in ischemic heart disease can attenuate cardiac inflammation and oxidative stress in a microenvironment, regulate cell survival and apoptosis, nourish CMs, enhance mature neovascularization, alleviate adverse ventricular remodeling after infarction and enhance ventricular function. In this review, we introduce the definition and discuss the origin and biological characteristics of EPCs and summarize the mechanisms of EPC recruitment in ischemic heart disease. We focus on the crosstalk between EPCs and endothelial cells (ECs), smooth muscle cells (SMCs), CMs, cardiac fibroblasts (CFs), cardiac progenitor cells (CPCs), and MSCs during cardiac remodeling and repair. Finally, we discuss the translation of EPC therapy to the clinic and treatment strategies.

Non-coding RNAs as new autophagy regulators in cancer progression

Recent advances highlight that non-coding RNAs (ncRNAs) are emerging as fundamental regulators in various physiological as well as pathological processes by regulating macro-autophagy. Studies have disclosed that macro-autophagy, which is a highly conserved process involving cellular nutrients, components, and recycling of organelles, can be either selective or non-selective and ncRNAs show their regulation on selective autophagy as well as non-selective autophagy. The abnormal expression of ncRNAs will result in the impairment of autophagy and contribute to carcinogenesis and cancer progression by regulating both selective autophagy as well as non-selective autophagy. This review focuses on the regulatory roles of ncRNAs in autophagy and their involvement in cancer which may provide valuable therapeutic targets for cancer management.

MicroRNA‑126 and VEGF enhance the function of endothelial progenitor cells in acute myocardial infarction

Previous studies have found that microRNA-126 (miR-126) overexpression can exert beneficial effects on endothelial function and angiogenesis. The role of miR-126 was previously reported to be by directly limiting the activities of negative regulators of the vascular endothelial growth factor (VEGF) pathway, such as PI3K regulation subunit 2 (PIK3R2). The aim of the present study was to investigate the role of the miR-126/PIK3R2/VEGF axis in endothelial progenitor cells (EPCs) under hypoxic conditions. An in vitro hypoxia model in EPCs was established by exposing EPCs to hypoxia (O²/N²/CO², 1/94/5) for 72 h, before reverse transcription-quantitative PCR (RT-qPCR) and western blot analyzes were used to measure miR-126 and PIK3R2 expression in EPCs. The proliferation, migration and tube-forming ability of the transfected cells were measured using MTT, Transwell and tube formation assays, respectively. miR-126 expression was found to be lower in EPCs in the hypoxia group compared with that in the control group (P<0.01). The expression of PIK3R2, a direct target gene of miR-126, was found to be higher in the hypoxia group compared with that in the control group (P<0.01). miR-126 mimic and VEGF-plasmid co-transfection improved the proliferation, migration, tube-forming ability and restored the phosphorylation of AKT in EPCs under hypoxic conditions (all P<0.01). In addition, the effects of miR-126 mimic on hypoxia-induced EPCs were reversed by PIK3R2-plasmid co-transfection, whilst the effects of VEGF-plasmid were enhanced further by co-transfection with the miR-126 mimic. In conclusion, miR-126 promoted the functions of EPCs under hypoxic conditions by negatively targeting PIK3R2, whilst the combined overexpression of miR-126 and VEGF enhanced these aforementioned effects.

Identification of Hub Genes Associated with Abnormal Endothelial Function in Early Coronary Atherosclerosis

Abnormal coronary endothelial function is an important step in the development of atherosclerosis. Coronary atherosclerosis is one of the main causes of death worldwide. We constructed a co-expression network to identify hub genes associated with abnormal coronary endothelial function in early coronary atherosclerosis. In brief, we used the GSE132651 dataset from the gene expression omnibus database. The top 5000 genes with greatest variances were used for weighted gene co-expression network analysis, and the module most strongly correlated with abnormal coronary endothelial function was chosen as key module. Functional enrichment analysis was performed for genes in the key module, a protein-protein interaction network was constructed to find hub genes, and gene set enrichment analysis (GSEA) was also performed. Genes were classified into 7 modules, with the midnightblue module being the one that was most related to abnormal coronary endothelial function and containing genes enriched in DNA replication, cell cycle, nucleotide excision repair, and Human T-cell leukemia virus 1 infection. We identified nine hub genes (HOXC5, PRND, PADI3, RC3H1, DAPP1, SIT1, DRICH1, GPRIN2, and RHO), which differently expressed in abnormal and normal coronary endothelial function samples. GSEA suggested that samples associated with abnormal coronary endothelial function and highly expressed hub genes were linked with immune, coagulation, hypoxia, and angiogenesis processes. These hub genes, their expression pattern, and pathways may be involved in the development of abnormal coronary endothelial function and promotion of early coronary atherosclerosis.

Circ-Klhl8 overexpression increased the therapeutic effect of EPCs in diabetic wound healing via the miR-212-3p/SIRT5 axis

Previous studies found that hypoxic pretreatment of endothelial progenitor cells (EPCs) prior to transplantation had a greater therapeutic effect than untreated EPCs in promoting diabetic wound healing. However, the exact mechanism is uncertain. Here, circRNA expression in EPCs after hypoxic treatment was investigated. High-throughput sequencing was used to assess abnormal expression by EPCs of circular RNAs (circRNAs) following hypoxic pretreatment. Additionally, an in vivo full-thickness skin defect mouse model was used to assess the effects of transplanted EPCs on diabetic wound closure. Subsequently, the regulatory mechanism and targets were studied. The results showed that circ-Klhl8 overexpression suppressed hyper glucose-induced endothelial cell damage by activating autophagy. MiR-212-3p and SIRT5 were identified as the downstream targets of circ-Klhl8. Circ-Klhl8 overexpression promoted skin wound healing by regulating SIRT5-mediated autophagy. In conclusion, the study found that circ-Klhl8 overexpression increased the EPC therapeutic effect in promoting diabetic wound healing by targeting the miR-212-3p/SIRT5 axis.

The impact of cardiomotor rehabilitation on endothelial function in elderly patients with chronic heart failure

Background

To explore the effects of cardiac exercise rehabilitation on peripheral blood endothelial progenitor cells (EPC) in elderly patients with chronic heart failure.

Methods

80 elderly patients with chronic heart failure were selected from March 2017 to March 2019 and randomly divided into two groups (N = 40). The control group was treated routinely and walked freely for 30–60 min every day. The patients in the exercise rehabilitation group developed a cardiac exercise rehabilitation plan. Then, cardiac function and peripheral blood B-natriuretic peptide (BNP) levels in the two groups were compared. The cell viability, proliferation, apoptosis, and invasion ability of EPCs were detected. The levels of the PI3K/AKT pathway and eNOS and VEGF were compared.

Results

There were no significant differences in all indexes between the two groups before treatment (P > 0.05), and both improved significantly after treatment (P < 0.05). After treatment, LVEF and LVFS in the exercise rehabilitation group were significantly higher than those in the control group (P < 0.05), and LVEDD and LVESD were significantly lower than those in the control group (P < 0.05). The BNP level in the exercise rehabilitation group was significantly lower than that in the control group (P < 0.05). The cell viability, proliferation, invasion ability of EPC, and the levels of PI3K, AKT, eNOS, and VEGF mRNA and protein in the exercise rehabilitation group were significantly higher than those in the control group. Apoptosis rate was significantly lower than those in the control group (P < 0.05).

Conclusions

Visceral exercise rehabilitation can improve cardiac ejection and myocardial function in elderly patients with chronic heart failure, and can promote the vitality, proliferation, and invasion of peripheral blood EPC, and promote the expression of eNOS and VEGF by upregulating the PI3K/AKT pathway to promote angiogenesis and endothelial function.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02327-5.

Extracorporeal Cardiac Shock Waves Therapy Improves the Function of Endothelial Progenitor Cells After Hypoxia Injury via Activating PI3K/Akt/eNOS Signal Pathway

Background: Extracorporeal cardiac shock waves (ECSW) have great potential in the treatment of coronary heart disease. Endothelial progenitor cells (EPCs) are a class of pluripotent progenitor cells derived from bone marrow or peripheral blood, which have the capacity to migrate to ischemic myocardium and differentiate into mature endothelial cells and play an important role in neovascularization and endothelial repair. In this study, we investigated whether ECSW therapy can improve EPCs dysfunction and apoptosis induced by hypoxia and explored the underlying mechanisms.

Methods: EPCs were separated from ApoE gene knockout rat bone marrow and identified using flow cytometry and fluorescence staining. EPCs were used to produce in vitro hypoxia-injury models which were then divided into six groups: Control, Hypoxia, Hypoxia + ECSW, Hypoxia + LY294002 + ECSW, Hypoxia + MK-2206 + ECSW, and Hypoxia + L-NAME + ECSW. EPCs from the Control, Hypoxia, and Hypoxia + ECSW groups were used in mRNA sequencing reactions. mRNA and protein expression levels were analyzed using qRT-PCR and western blot analysis, respectively. Proliferation, apoptosis, adhesion, migration, and angiogenesis were measured using CCK-8, flow cytometry, gelatin, transwell, and tube formation, respectively. Nitric oxide (NO) levels were measured using an NO assay kit.

Results: Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis showed that differentially expressed genes were enriched in cancer signaling, PI3K-Akt signaling, and Rap1 signaling pathways. We selected differentially expressed genes in the PI3K-Akt signaling pathway and verified them using a series of experiments. The results showed that ECSW therapy (500 shots at 0.09 mJ/mm²) significantly improved proliferation, adhesion, migration, and tube formation abilities of EPCs following hypoxic injury, accompanied by upregulation of p-PI3K, p-Akt, p-eNOS, Bcl-2 protein and NO, PI3K, and Akt mRNA expression, and downregulation of Bax and Caspase3 protein expression. All these effects of ECSW were eliminated using inhibitors specific to PI3K (LY294002), Akt (MK-2206), and eNOS (L-NAME).

Conclusion: ECSW exerted a strong repaired effect on EPCs suffering inhibited hypoxia injury by inhibiting cell apoptosis and promoting angiogenesis, mainly through activating the PI3K/Akt/eNOS signaling pathway, which provide new evidence for ECSW therapy in CHD.

Mesenchymal stem cell-derived extracellular vesicles as probable triggers of radiation-induced heart disease

BACKGROUND

Radiation-induced heart disease has been reported, but the underlying mechanisms remain unclear. Mesenchymal stem cells (MSCs), also residing in the heart, are highly susceptible to radiation. We examined the hypothesis that the altered secretion of extracellular vesicles (EVs) from MSCs is the trigger of radiation-induced heart disease.

METHODS

By exposing human placental tissue-derived MSCs to 5 Gy γ-rays, we then isolated EVs from the culture medium 48 h later and evaluated the changes in quantity and quality of EVs from MSCs after radiation exposure. The biological effects of EVs from irradiated MSCs on HUVECs and H9c2 cells were also examined.

RESULTS

Although the amount and size distribution of EVs did not differ between the nonirradiated and irradiated MSCs, miRNA sequences indicated many upregulated or downregulated miRNAs in irradiated MSCs EVs. In vitro experiments using HUVEC and H9c2 cells showed that irradiated MSC-EVs decreased cell proliferation (P < 0.01), but increased cell apoptosis and DNA damage. Moreover, irradiated MSC-EVs impaired the HUVEC tube formation and induced calcium overload in H9c2 cells.

CONCLUSIONS

EVs released from irradiated MSCs show altered miRNA profiles and harmful effects on heart cells, which provides new insight into the mechanism of radiation-related heart disease risks.

Autophagy-related signaling pathways are involved in cancer (Review)

Autophagy is a self-digestion process in cells that can maintain energy homeostasis under normal circumstances. However, misfolded proteins, damaged mitochondria and other unwanted components in cells can be decomposed and reused via autophagy in some specific cases (including hypoxic stress, low energy states or nutrient deprivation). Therefore, autophagy serves a positive role in cell survival and growth. However, excessive autophagy may lead to apoptosis. Furthermore, abnormal autophagy may lead to carcinogenesis and promote tumorigenesis in normal cells. In tumor cells, autophagy may provide the energy required for excessive proliferation, promote the growth of cancer cells, and evade apoptosis caused by certain treatments, including radiotherapy and chemotherapy, resulting in increased treatment resistance and drug resistance. On the other hand, autophagy leads to an insufficient nutrient supply in cancer cells and the destruction of energy homeostasis, thereby inducing cancer cell apoptosis. Therefore, understanding the mechanism of the double-edged sword of autophagy is crucial for the treatment of cancer. The present review summarizes the signaling pathways and key factors involved in autophagy and cancer to provide possible strategies for treating tumors.

The lncRNA PAHRF functions as a competing endogenous RNA to regulate MST1 expression by sponging miR-23a-3p in pulmonary arterial hypertension

BACKGROUND

Emerging evidence has shown that long non-coding RNA (lncRNA) plays important roles in the development of pulmonary arterial hypertension (PAH). However, some new lncRNAs in patients with PAH are still lacking research. Herein, we examined the expression and role of lncRNA (pulmonary arterial hypertension related factor, PAHRF) in PAH.

METHODS

LncRNA PAHRF expression and localization were analyzed by realtime PCR and fluorescence in situ hybridization. Proliferation and apoptosis were detected by MTT, CCK-8, EDU staining, JC-1 assay, flow cytometry and western blotting. Luciferase activity assay was used to identify PAHRF/ miR-23a-3p/serine/threonine kinase 4 (STK4/MST1) interaction.

RESULTS

LncRNA PAHRF was down-regulated in both the PAs of PAH patients and hypoxic human pulmonary artery smooth muscle cells (PASMCs). The overexpression of PAHRF inhibited the proliferation and promoted the apoptosis of PASMCs. Similarly, we also found PAHRF overexpression decreased the proliferation under hypoxia condition. Knockdown of PAHRF exerted the opposite effects. Luciferase activity assay proved molecular binding between PAHRF and hsa-miR-23a-3p. Moreover, MST1 was confirmed to be the putative target gene and regulated by PAHRF/miR-23a-3p. In addition, we explored the molecular mechanism regulating the expression of miR-23a-3p, and found that lncRNA PAHRF acted as an endogenous sponge for miR-23a-3p, and silencing lncRNA PAHRF could up-regulate the expression of miR-23a-3p. On the contrary, PAHRF-overexpressing plasmid inhibited the expression of miR-23a-3p in hypoxia.

CONCLUSIONS

Our present study reveals a novel PAH regulating model that is composed of PAHRF, miR-23a-3p, and MST1. The aim of this study is probably going to provide a new explanation and give a further understanding of the occurrence of vascular remodeling in PAH from the perspective competing endogenous RNA hypothesis.

Low-Energy Shockwave Treatment Promotes Endothelial Progenitor Cell Homing to the Stenotic Pig Kidney

Endothelial progenitor cells (EPCs) patrols the circulation and contributes to endothelial cell regeneration. Atherosclerotic renal artery stenosis (ARAS) induces microvascular loss in the stenotic kidney (STK). Low-energy shockwave therapy (SW) can induce angiogenesis and restore the STK microcirculation, but the underlying mechanism remains unclear. We tested the hypothesis that SW increases EPC homing to the swine STK, associated with capillary regeneration. Normal pigs and pigs after 3 wk of renal artery stenosis were treated with six sessions of low-energy SW (biweekly for three consecutive weeks) or left untreated. Four weeks after completion of treatment, we assessed EPC (CD34+/KDR+) numbers and levels of the homing-factor stromal cell-derived factor (SDF)-1 in the inferior vena cava and the STK vein and artery, as well as urinary levels of vascular endothelial growth factor (VEGF) and integrin-1β. Subsequently, we assessed STK morphology, capillary count, and expression of the proangiogenic growth factors angiopoietin-1, VEGF, and endothelial nitric oxide synthase ex vivo. A 3-wk low-energy SW regimen improved STK structure, capillary count, and function in ARAS+SW, and EPC numbers and gradients across the STK decreased. Plasma SDF-1 and renal expression of angiogenic factors were increased in ARAS+SW, and urinary levels of VEGF and integrin-1β tended to rise during the SW regimen. In conclusion, SW improves ischemic kidney capillary density, which is associated with, and may be at least in part mediated by, promoting EPCs mobilization and homing to the stenotic kidney.

LncRNAs as Therapeutic Targets for Autophagy-involved Cardiovascular Diseases: A Review of Molecular Mechanism and T herapy Strategy

BACKGROUND

Cardiovascular diseases (CVDs) remain the leading cause of death worldwide. The concept of precision medicine in CVD therapy today requires the incorporation of individual genetic and environmental variability to achieve personalized disease prevention and tailored treatment. Autophagy, an evolutionarily conserved intracellular degradation process, has been demonstrated to be essential in the pathogenesis of various CVDs. Nonetheless, there have been no effective treatments for autophagy- involved CVDs. Long noncoding RNAs (lncRNAs) are noncoding RNA sequences that play versatile roles in autophagy regulation, but much needs to be explored about the relationship between lncRNAs and autophagy-involved CVDs.

SUMMARY

Increasing evidence has shown that lncRNAs contribute considerably to modulate autophagy in the context of CVDs. In this review, we first summarize the current knowledge of the role lncRNAs play in cardiovascular autophagy and autophagy-involved CVDs. Then, recent developments of antisense oligonucleotides (ASOs) designed to target lncRNAs to specifically modulate autophagy in diseased hearts and vessels are discussed, focusing primarily on structure-activity relationships of distinct chemical modifications and relevant clinical trials.

PERSPECTIVE

ASOs are promising in cardiovascular drug innovation. We hope that future studies of lncRNA-based therapies would overcome existing technical limitations and help people who suffer from autophagy-involved CVDs.

Down-regulation of miR-361-5p promotes the viability, migration and tube formation of endothelial progenitor cells via targeting FGF1

Transplantion of bone marrow-derived endothelial progenitor cells (EPCs) may be a novel treatment for deep venous thrombosis (DVT). The present study probed into the role of microRNA (miR)-361-5p in EPCs and DVT recanalization. EPCs were isolated from male Sprague-Dawley (SD) rats and identified using confocal microscopy and flow cytometry. The viability, migration and tube formation of EPCs were examined using MTT assay, wound-healing assay and tube formation assay, respectively. Target gene and potential binding sites between miR-361-5p and fibroblast growth factor 1 (FGF1) were predicted by StarBase and confirmed by dual-luciferase reporter assay. Relative expressions of miR-361-5p and FGF1 were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot as needed. A DVT model in SD rats was established to investigate the role of EPC with miR-361-5p antagomir in DVT by Hematoxylin-Eosin (H&E) staining. EPC was identified as 87.1% positive for cluster of difference (CD)31, 2.17% positive for CD133, 85.6% positive for von Willebrand factor (vWF) and 94.8% positive for vascular endothelial growth factor receptor-2 (VEGFR2). MiR-361-5p antagomir promoted proliferation, migration and tube formation of EPCs and up-regulated FGF1 expression, thereby dissolving thrombus in the vein of DVT rats. FGF1 was the target of miR-361-5p, and overexpressed FGF1 reversed the effects of up-regulating miR-361-5p on suppressing EPCs. Down-regulation of miR-361-5p enhanced thrombus resolution in vivo and promoted EPC viability, migration and angiogenesis in vitro through targeting FGF1. Therefore, miR-361-5p may be a potential therapeutic target for DVT recanalization.

Promotion of Aerobic Exercise Induced Angiogenesis Is Associated With Decline in Blood Pressure in Hypertension: Result of EXCAVATION-CHN1

[Figure: see text].

Control of Gene Expression by Exosome-Derived Non-Coding RNAs in Cancer Angiogenesis and Lymphangiogenesis

Abstract: Tumour angiogenesis and lymphangiogenesis are hallmarks of cancer and have been associated with tumour progression, tumour metastasis and poor patient prognosis. Many factors regulate angiogenesis and lymphangiogenesis in cancer including non-coding RNAs which are a category of RNAs that do not encode proteins and have important regulatory functions at transcriptional and post-transcriptional levels. Non-coding RNAs can be encapsulated in extracellular vesicles called exosomes which are secreted by tumour cells or other cells in the tumour microenvironment and can then be taken up by the endothelial cells of blood vessels and lymphatic vessels. The "delivery" of these non-coding RNAs to endothelial cells in tumours can facilitate tumour angiogenesis and lymphangiogenesis. Here we review recent findings about exosomal non-coding RNAs, specifically microRNAs and long non-coding RNAs, which regulate tumour angiogenesis and lymphangiogenesis in cancer. We then focus on the potential use of these molecules as cancer biomarkers and opportunities for exploiting ncRNAs for the treatment of cancer.

Mechanical loading stimulates bone angiogenesis through enhancing type H vessel formation and downregulating exosomal miR-214-3p from bone marrow-derived mesenchymal stem cells

Exosomes are important transporters of miRNAs, which play varying roles in the healing of the bone fracture. Angiogenesis is one of such critical events in bone healing, and we previously reported the stimulatory effect of mechanical loading in vessel remodeling. Focusing on type H vessels and exosomal miR-214-3p, this study examined the mechanism of loading-driven angiogenesis. MiRNA sequencing and qRT-PCR revealed that miR-214-3p was increased in the exosomes of the bone-losing ovariectomized (OVX) mice, while it was significantly decreased by knee loading. Furthermore, compared to the OVX group, exosomes, derived from the loading group, promoted the angiogenesis of endothelial cells. In contrast, exosomes, which were transfected with miR-214-3p, decreased the angiogenic potential. Notably, knee loading significantly improved the microvascular volume, type H vessel formation, and bone mineral density and contents, as well as BV/TV, Tb.Th, Tb.N, and Tb.Sp. In cell cultures, the overexpression of miR-214-3p in endothelial cells reduced the tube formation and cell migration. Collectively, this study demonstrates that knee loading promotes angiogenesis by enhancing the formation of type H vessels and downregulating exosomal miR-214-3p.

Orexin-A protects against cerebral ischemia-reperfusion injury by inhibiting excessive autophagy through OX1R-mediated MAPK/ERK/mTOR pathway

Orexin A (OXA) is a neuroprotective peptide that exerts protective effects on multiple physiological and pathological processes. Activation of autophagy is linked to the occurrence of cerebral ischemia-reperfusion injury (CIRI); however, its function remains incompletely understood. In this study, OXA was sought to exert its neuroprotective role by regulating autophagy in oxygen and glucose deprivation and reoxygenation (OGD/R) model and middle cerebral artery occlusion (MCAO) model of rats, and to elucidate the underlying molecular mechanisms. Acridine orange (AO) staining was used to evaluate autophagic vacuoles. Cell viability was measured by CCK8. The levels of p-ERK_1/2, t-ERK_1/2, p-mTOR, LC3B, Beclin 1, and p62 were evaluated by western blotting. Apoptosis rate was detected by Hoechst 33342 staining and Terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL). OXA treatment alleviated neuronal apoptosis and significantly inhibited autophagy activity. Mechanistically, OXA exerted its neuroprotective effects in vivo and in vitro by suppressing over-activated autophagy by modulating OX1R-mediated MAPK/ERK/mTOR pathway. The results of this study elucidate the roles of autophagy in CIRI and the mechanisms underlying the neuroprotective action of OXA. Our findings could facilitate the development of novel therapeutics for ischemic stroke.

MMP-1 promotes osteogenic differentiation of human bone marrow mesenchymal stem cells via the JNK and ERK pathway

Enhancing the functions of mesenchymal stem cells (MSCs) is considered a potential approach for promoting tissue regeneration. In this study, we investigated the effects of Matrix Metalloproteinase-1 (MMP-1) on bone marrow mesenchymal stem cells (BMSCs) and its mechanism. Our results showed that knockdown of MMP-1 impeded scratch closure, attenuated proliferation, inhibited ALP activity, ALP denser staining and mineralization in vitro, and decreased expression of RUNX2, OSX, OPN and OCN in BMSCs, while 20 ng/mL recombinant human MMP-1 protein (rhMMP-1) significantly accelerated scratch closure, enhanced proliferation, ALP activity, ALP denser staining and mineralization in vitro, and increased expression of RUNX2, OSX, OPN and OCN. In addition, knockdown of MMP-1 inhibited the expression of phosphorylated c-Jun N-terminal kinase (p-JNK) and phosphorylated extracellular regulated protein kinases (p-ERK), while 20 ng/mL rhMMP-1 increased the expression of p-JNK and p-ERK in BMSCs. Furthermore, inhibition of c-Jun N-terminal kinase (JNK) and extracellular regulated protein kinases (ERK) by their inhibitor SP600125 and PD98059 dramatically blocked MMP-1-enhanced ALP activity and mineralization in BMSCs. Our results revealed that MMP-1 could accelerate the osteogenic differentiation potentials of BMSCs via the JNK and ERK pathway, providing the mechanism underlying MSC biology and identifying a potential target for improving bone tissue regeneration.

Exogenous bone marrow derived-putative endothelial progenitor cells attenuate ischemia reperfusion-induced vascular injury and renal fibrosis in mice dependent on pericytes

Rationale: Capillaries are composed of endothelial cells and the surrounding mural cells, pericytes. Microvascular repair after injury involves not only the proliferation of endothelial cells but also pericyte-based vessel stabilization. Exogenous bone marrow derived-putative endothelial progenitor cells (b-pEPCs) have the potential for vascular repair; however, their effect on vascular structure stabilization and pericyte-related pathobiological outcomes in the injured kidney has not been fully examined.

Methods: We applied ischemia-reperfusion (IR) to induce renal vascular injury and renal fibrosis in mice. Platelet-derived growth factor receptor β (PDGFR-β)-DTR-positive mice were generated to deplete pericytes, and exogenous b-pEPCs and the PDGFR-β ligand, PDGF chain B (PDGF-BB), were employed to explore the relationship among b-pEPCs, pericytes, vascular repair, and early renal fibrosis.

Results: Administration of b-pEPCs reduced IR-induced pericyte-endothelial detachment, pericyte proliferation, and myofibroblast transition via a paracrine mode, which preserved not only vascular stabilization but also ameliorated IR-initiated renal fibrosis. PDGF-BB upregulated the expression of PDGFR-β, exacerbated vascular abnormality, and pericyte-myofibroblast transition, which were ameliorated by b-pEPCs administration. The exogenous b-pEPCs and their culture medium (CM) induced vascular injury protection, and renal fibrosis was blocked by selective deletion of pericytes.

Conclusion: Exogenous b-pEPCs directly protect against IR-induced vascular injury and prevent renal fibrosis by inhibiting the activation of PDGFR-β-positive pericytes.

TUG1 enhances high glucose-impaired endothelial progenitor cell function via miR-29c-3p/PDGF-BB/Wnt signaling

BACKGROUND

Diabetes is associated with the dysfunction of endothelial progenitor cells (EPCs), characterized as impaired angiogenesis, a phenomenon thought to be involved in the development of diabetic foot. lncRNA plays an essential role in microvascular dysfunction and signaling pathways in patients with diabetes. lncRNA taurine upregulated gene 1 (TUG1) participates in angiogenesis in various cells. However, the mechanisms of TUG1 activity in EPCs have not been elucidated.

METHODS

We isolated and then characterized EPCs from the peripheral blood of mice using immunofluorescence and flow cytometry. Western blot detected the wnt/β-catenin pathway in high glucose-treated EPCs. Bioinformatics analysis predicted a putative binding site for TUG1 on miR-29c-3p. The interactions among TUG1, platelet-derived growth factor-BB (PDGF-BB), and miR-29c-3p were analyzed by luciferase assays. In vivo, diabetic mouse ischemic limb was treated with normal saline or TUG1 overexpression lentiviruses.

RESULTS

We found that EPC migration, invasion, and tube formation declined after treatment with high glucose, but improved with TUG1 overexpression. Mechanically, wnt/β-catenin pathway and autophagy were involved in the function of TUG1 overexpression in high glucose-treated EPCs. Moreover, TUG1 regulates the PDGF-BB/wnt pathway and function of high glucose-treated EPCs via miR-29c-3p. In vivo, injection of TUG1 lentivirus in a diabetic mouse ischemic limb model stimulated angiogenesis.

CONCLUSIONS

Our findings suggest that TUG1 restores high glucose-treated EPC function by regulating miR-29c-3p/PDGF-BB/Wnt signaling.

Clarification of the Role of miR-9 in the Angiogenesis, Migration, and Autophagy of Endothelial Progenitor Cells Through RNA Sequence Analysis

We have previously reported that miR-9 promotes the homing, proliferation, and angiogenesis of endothelial progenitor cells (EPCs) by targeting transient receptor potential melastatin 7 via the AKT autophagy pathway. In this way, miR-9 promotes thrombolysis and recanalization following deep vein thrombosis (DVT). However, the influence of miR-9 on messenger RNA (mRNA) expression profiles of EPCs remains unclear. The current study comprises a comprehensive exploration of the mechanisms underlying the miR-9-regulated angiogenesis of EPCs and highlights potential treatment strategies for DVT. We performed RNA sequence analysis, which revealed that 4068 mRNAs were differentially expressed between EPCs overexpressing miR-9 and the negative control group, of which 1894 were upregulated and 2174 were downregulated. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicated that these mRNAs were mainly involved in regulating cell proliferation/migration processes/pathways and the autophagy pathway, both of which represent potential EPC-based treatment strategies for DVT. Reverse transcriptase quantitative polymerase chain reaction confirmed the changes in mRNA expression related to EPC angiogenesis, migration, and autophagy. We also demonstrate that miR-9 promotes EPC migration and angiogenesis by regulating FGF5 directly or indirectly. In summary, miR-9 enhances the expression of VEGFA, FGF5, FGF12, MMP2, MMP7, MMP10, MMP11, MMP24, and ATG7, which influences EPC migration, angiogenesis, and autophagy. We provide a comprehensive evaluation of the miR-9-regulated mRNA expression in EPCs and highlight potential targets for the development of new therapeutic interventions for DVT.

Non-coding RNAs regulate angiogenic processes

Angiogenesis has critical roles in numerous physiologic processes during embryonic and adult life such as wound healing and tissue regeneration. However, aberrant angiogenic processes have also been involved in the pathogenesis of several disorders such as cancer and diabetes mellitus. Vascular endothelial growth factor (VEGF) is implicated in the regulation of this process in several physiologic and pathologic conditions. Notably, several non-coding RNAs (ncRNAs) have been shown to influence angiogenesis through modulation of expression of VEGF or other angiogenic factors. In the current review, we summarize the function and characteristics of microRNAs and long non-coding RNAs which regulate angiogenic processes. Understanding the role of these transcripts in the angiogenesis can facilitate design of therapeutic strategies to defeat the pathogenic events during this process especially in the human malignancies. Besides, angiogenesis-related mechanisms can improve tissue regeneration after conditions such as arteriosclerosis, myocardial infarction and limb ischemia. Thus, ncRNA-regulated angiogenesis can be involved in the pathogenesis of several disorders.

miR-22-3p Suppresses Endothelial Progenitor Cell Proliferation and Migration via Inhibiting Onecut 1 (OC1)/Vascular Endothelial Growth Factor A (VEGFA) Signaling Pathway and Its Clinical Significance in Venous Thrombosis

Background

Proliferation and migration play crucial roles in various physiological processes, especially in injured endothelial repair. Endothelial progenitor cells (EPCs), as the precursors of endothelial cell, are involved in the regeneration of the endothelial lining of blood vessels. Furthermore, EPCs were found to be a potential choice for venous thrombosis (VT) treatment.

Material/Methods

EPCs were isolated from human peripheral blood of healthy adults and VT patients. Differently expressed micro(mi)RNAs were examined by quantitative real-time polymerase chain reaction, after which proliferative capacity and migration effect were tested by Cell-Counting Kit 8, scratch wound assay, and transwell assays. Bioinformatic analysis was applied to investigate the potential target messenger ribonucleic acid and a dual-luciferase reporting system was utilized to confirm the binding of miR-22-3p to its target gene. Western blot was carried out to detect candidate protein expression level. Finally, miR-22-3p expression was monitored in VT patients during follow-up to assess its correlation with prognosis of VT.

Results

Our data revealed that miR-22-3p was upregulated in EPCs derived from deep VT (DVT) individuals and suppression of miR-22-3p contributed to proliferation and migration of EPCs. In addition, miR-22-3p/onecut 1 (OC1)/vascular endothelial growth factor A (VEGFA) signaling pathway was involved in regulating EPC migration and proliferation. In addition, lower expression of miR-22-3p in DVT patients indicated decreased risk of VT recurrence.

Conclusions

Our results suggest that miR-22-3p regulates OC1/VEGFA signaling and is involved in regulating EPC proliferation and migration. The expression level of miR-22-3p could be monitored to predict DVT patients’ prognosis.

Metformin inhibits angiogenesis of endothelial progenitor cells via miR-221-mediated p27 expression and autophagy

Aim: To explore the underlying mechanisms of metformin on the angiogenic capacity of endothelial progenitor cells (EPCs). Results: EPC growth and miR-221 expression decreased concentration-dependence with metformin, and a negative correlation was observed between miR-221 expression and metformin concentration (p < 0.001). miR-221 overexpression using a mimic decreased the metformin-mediated angiogenic effects in EPCs (p < 0.01). Metformin increased p27 and LC3II expression and AMP-activated protein kinase (AMPK) phosphorylation, and decreased p62 expression, while miR-221 overexpression reversed the effects of metformin. Additionally, AMPK inhibition by compound C reversed the increase in p27 and LC3II levels and AMPK phosphorylation or miR-221 siRNA treatment. Conclusion: Metformin inhibits the angiogenic capacity of EPCs. The underlying mechanism involves AMPK-mediated autophagy pathway activity and increases miR-221-mediated p27 expression.

hsa_circ_0058092 protects against hyperglycemia‑induced endothelial progenitor cell damage via miR‑217/FOXO3

Circular RNAs (circRNAs) regulate the expression of genes that are critical for various biological and pathological processes. Previous studies have reported that the expression of hsa_circ_0058092 is decreased in patients with diabetes mellitus (DM); however, the specific role of this circRNA in DM is unknown. In the present study, endothelial progenitor cells (EPCs) were isolated and a decreased hsa_circ_0058092 expression was found under conditions of hyperglycemia (HG). The overexpression of hsa_circ_0058092 protected the EPCs against HG‑induced damage by preserving cell survival, proliferation, migration and angiogenic differentiation. The overexpression of hsa_circ_0058092 also decreased the HG‑induced increase in NADPH‑oxidase proteins and inflammatory cytokines. Further investigation revealed that the overexpression of hsa_circ_0058092 enhanced FOXO3 expression, which was mediated through the interaction with miR‑217. Furthermore, the upregulation of miR‑217 or the downregulation of FOXO3 abolished the protective effects of hsa_circ_0058092 against HG‑induced EPC damage. On the whole, these data suggest that hsa_circ_0058092 acts via the miR‑217/FOXO3 pathway to protect against EPCs HG‑induced damage, and to preserve the migration and angiogenesis of EPCs.

LncRNA WTAPP1 promotes cancer cell invasion and migration in NSCLC by downregulating lncRNA HAND2-AS1

BACKGROUND

Long non-coding RNA (lncRNA) Wilms Tumor 1 Associated Protein Pseudogene 1 (WTAPP1) has been reported to be a critical player in the angiogenesis and migration of endothelial progenitor cells, while its involvement in cancer biology remains unknown. This study was carried out to investigate the role of WTAPP1 in non-small cell lung cancer (NSCLC).

METHODS

The expression of WTAPP1 and lncRNA HAND2 Antisense RNA 1 (HAND2-AS1) in plasma and tissues from NSCLC patients was detected by qRT-PCR. A 5-year follow-up study was carried out to explore the prognostic value of WTAPP1 for NSCLC. Overexpression experiments were performed to analyze the interaction between WTAPP1 and HAND2-AS1. Cell invasion and migration were evaluated by Transwell assays.

RESULTS

The expression of WTAPP1 was upregulated in NSCLC. The survival analysis showed that low plasma levels of WTAPP1 were accompanied with high survival rate. HAND2-AS1 was downregulated in NSCLC and inversely correlated with WTAPP1 across tumor tissues. Overexpression of WTAPP1 resulted in downregulation of HAND2-AS1 in NSCLC cells, while overexpression of HAND2-AS1 did not affect the expression of WTAPP1. Overexpression of WTAPP1 led to promoted, while overexpression of HAND2-AS1 resulted in inhibited invasion and migration of NSCLC cells. In addition, overexpression of HAND2-AS1 partially attenuated the effects of overexpressing WTAPP1. In addition, WTAPP1 did not affect cancer cell proliferation.

CONCLUSION

WTAPP1 may promote cancer cell invasion and migration in NSCLC by downregulating lncRNA HAND2-AS1.

Long non-coding RNA TPT1-AS1 promotes angiogenesis and metastasis of colorectal cancer through TPT1-AS1/NF90/VEGFA signaling pathway

LncRNAs have been proven closely correlated to tumor progression. A recent study identified LncRNA TPT1-AS1 (TPT1-AS1) as one of the liver-metastasis associated LncRNAs in colorectal cancer (CRC). In this study, we report that TPT1-AS1 is upregulated in CRC tissues, which is associated with poor prognosis. Functional assays unravel a pro-angiogenesis and metastasis role of TPT1-AS1. Mechanistically, Flexmap 3D assays reveal that TPT1-AS1 upregulates the VEGFA secretion in CRC cells. RNA immunoprecipitation and mRNA stability assays further show that TPT1-AS1 interacts with nuclear factor 90 (NF90) and subsequently promotes the association between NF90 and VEGFA mRNA, which leads to the upregulation of VEGFA mRNA stability. Therefore, we elucidate a new regulatory mechanism of TPT1-AS1 in CRC angiogenesis and targeting the TPT1-AS1/NF90/VEGFA axis may provide a useful strategy for diagnosis and treatment for colorectal cancer patients.