Upregulation of miR-126-3p promotes human saphenous vein endothelial cell proliferation in vitro and prevents vein graft neointimal formation ex vivo and in vivo

The potential therapeutic effect of human umbilical cord mesenchymal stem cell-derived exosomes in bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a chronic lung disease of preterm infants, with its incidence rising due to improved survival rates of these infants. BPD results from a combination of prenatal and postnatal factors, such as mechanical ventilation, oxygen toxicity, and infections, all of which significantly impact the prognosis and growth of affected infants. Current treatment options for BPD are largely supportive and do not address the underlying pathology. Exosomes are cell-derived bilayer-enclosed membrane structures enclosing proteins, lipids, RNAs, growth factors, cytokines and metabolites. They have become recognized as crucial regulators of intercellular communication in various physiological and pathological processes. Previous studies have revealed the therapeutic potential of human umbilical cord mesenchymal stem cells-derived exosomes (HUCMSCs-Exos) in promoting tissue repair and regeneration. Therefore, HUCMSCs-Exos maybe a promising and effective therapeutic modality for BPD. In this review, we firstly provide a comprehensive overview of BPD, including its etiology and the mechanisms of lung injury. Then we detail the isolation, characterization, and contents of HUCMSCs-Exos, and discuss their potential mechanisms of HUCMSCs-Exos in BPD treatment. Additionally, we summarize current clinical trials and discuss the challenges in translating these findings from bench to bedside. This review aims to lay the groundwork for future clinical applications of HUCMSCs-Exos in treating BPD.

Glutathione S-Transferase α4 Alleviates Hyperlipidemia-Induced Vascular Neointimal Hyperplasia in Arteriovenous Grafts via Inhibiting Endoplasmic Reticulum Stress

ABSTRACT

Neointimal hyperplasia causes the failure of coronary artery bypass grafting. Our previous studies have found that endothelial dysfunction is 1 candidate for triggering neointimal hyperplasia, but which factors are involved in this process is unclear. Glutathione S-transferase α4 (GSTA4) plays an important role in metabolizing 4-hydroxynonenal (4-HNE), a highly reactive lipid peroxidation product, which causes endothelial dysfunction or death. Here, we investigated the role of GSTA4 in neointima formation after arteriovenous grafts (AVGs) with or without high-fat diet (HFD). Compared with normal diet, HFD caused endothelial dysfunction and increased neointima formation, concomitantly accompanied by downregulated expression of GSTA4 at the mRNA and protein levels. In vitro, overexpression of GSTA4 attenuated 4-HNE-induced endothelial dysfunction and knockdown of GSTA4 aggravated endothelial dysfunction. Furthermore, silencing GSTA4 expression facilitated the activation of 4-HNE-induced endoplasmic reticulum stress and inhibition of endoplasmic reticulum stress pathway alleviated 4-HNE-induced endothelial dysfunction. In addition, compared with wild-type mice, mice with knockout of endothelial-specific GSTA4 (GSTA4 endothelial cell KO) exhibited exacerbated vascular endothelial dysfunction and increased neointima formation caused by HFD. Together, these results demonstrate the critical role of GSTA4 in protecting the function of endothelial cells and in alleviating hyperlipidemia-induced vascular neointimal hyperplasia in arteriovenous grafts.

Generation of a novel ex-vivo model to study re-endothelialization

Endothelial dysfunction initiates the pathogenesis of a myriad of cardiovascular diseases, yet the precise underlying mechanisms remain unclear. Current model utilises mechanical denudation of arteries resulting in an arterial-injury model with onset of intimal hyperplasia (IH). Our study shows that 5 min enzymatic denudation of human umbilical artery (hUA) lumen at 37 °C efficiently denudes hUA while maintaining vessel integrity without significantly increase intima-media thickness after 7 days in culture. This ex-vivo model will be a valuable tool in understanding the mechanism of re-endothelialization prior to smooth muscle cells (SMC) activation thus placating IH at an early stage.

Therapeutic Potentials of MicroRNA-126 in Cerebral Ischemia

Stroke is a leading cause of death and disability worldwide. It is among the most common neurological disorders with an 8-10% lifetime risk. Ischemic stroke accounts for about 85% of all strokes and damages the brain tissue via various damaging mechanisms. Following cerebral ischemia, the disrupted blood-brain barrier (BBB) leads to cerebral edema formation caused by activation of oxidative stress, inflammation, and apoptosis, targeting primarily endothelial cells. Activation of the protective mechanisms might favor fewer damages to the neural tissue. MicroRNA (miR)-126 is an endothelial cell-specific miR involved in angiogenesis. MiR-126 orchestrates endothelial progenitor cell functions under hypoxic conditions and could inhibit ischemia-induced oxidative stress and inflammation. It alleviates the BBB disruption by preventing an augment in matrix metalloproteinase level and halting the decrease in the junctional proteins, including zonula occludens-1 (ZO-1), claudin-5, and occludin levels. Moreover, miR-126 enhances post-stroke angiogenesis and neurogenesis. This work provides a therapeutic perspective for miR-126 as a new approach to treating cerebral ischemia.

miR-126-3p containing exosomes derived from human umbilical cord mesenchymal stem cells promote angiogenesis and attenuate ovarian granulosa cell apoptosis in a preclinical rat model of premature ovarian failure

Background

In our previous research, we found that overexpression of miR-126-3p in human umbilical cord MSCs (hucMSCs) promoted human umbilical vein endothelial cells angiogenic activities through exosome-mediated mechanisms. The present study aimed to investigate the role of miR-126-3p-modified hucMSCs derived exosomes (miR-126-3p-hucMSCs-exosomes) on the treatment of premature ovarian failure (POF).

Methods

Primary hucMSCs were isolated from human umbilical cords and identified by differentiation experiments and flow cytometry. miR-126-3p-hucMSCs were obtained by miR-126-3p lentivirus infection. miR-126-3p-hucMSCs-exosomes were purified by ultracentrifugation method and characterized by transmission electron microscopy and western blot analysis. Primary rat ovarian granulosa cells (OGCs) were collected from ovarian tissues and identified by cell immunohistochemistry. The effects of miR-126-3p-hucMSCs-exosomes and miR-126-3p on OGCs function were determined by cell proliferation and apoptosis assays in a cisplatin induced POF cell model. The levels of suitable target genes were analyzed by PCR and Western blot analysis and subsequent Dual-Luciferase reporter assay. The signal pathway was also analyzed by western blot analysis. A cisplatin-induced POF rat model was used to validate the therapeutic effects of miR-126-3p-hucMSCs-exosomes to treat POF. Ovarian function was evaluated by physical, enzyme-linked immunosorbent assay, and histological examinations in chemotherapy-treated rats. The angiogenesis and apoptosis of ovarian tissues were assessed by immunohistochemical staining and Western blots.

Results

Primary hucMSCs and miR-126-3p-hucMSCs-exosomes and primary rat OGCs were successfully isolated and identified. The cellular uptake experiments indicated that miR-126-3p-hucMSC-exosomes can be internalized into OGCs in vitro. Annexin V-FITC/PI staining and EDU assays revealed that both miR-126-3p-hucMSCs-exosomes and miR-126-3p promoted proliferation and inhibited apoptosis of OGCs damaged by cisplatin. PCR and western blot analysis and subsequent dual-luciferase reporter assay verified that miR-126-3p targets the sequence in the 3' untranslated region of PIK3R2 in OGCs. Further analysis showed that PI3K/AKT/mTOR signaling pathway took part in miR-126-3p/PIK3R2 mediated proliferation and apoptosis in OGCs. In rat POF model, administration of miR-126-3p-hucMSCs-exosomes increased E2 and AMH levels, increased body and reproductive organ weights and follicle counts, and reduced FSH levels. But more importantly, immunohistochemistry results indicated miR-126-3p-hucMSCs-exosomes significantly promoted ovarian angiogenesis and inhabited apoptosis in POF rats. Additionally, the analysis of angiogenic-related factors and apoptosis-related factors showed miR-126-3p-hucMSCs-exosomes had pro-angiogenesis and anti-apoptosis effect in rat ovaries.

Conclusions

Our findings revealed that hucMSCs-derived exosomes carrying miR-126-3p promote angiogenesis and attenuate OGCs apoptosis in POF, which highlighted the potential of exosomes containing miR-126-3p as an effective therapeutic strategy for POF treatment.

Recent advances in inhibiting atherosclerosis and restenosis: from pathogenic factors, therapeutic agents to nano-delivery strategies

Due to dominant atherosclerosis etiology, cardiovascular diseases (CVDs) remain the leading cause of morbidity and mortality worldwide. In clinical trials, advanced atherosclerotic plaques can be removed by angioplasty and vascular...

Diagnostic and Prognostic Value of miRNAs after Coronary Artery Bypass Grafting: A Review

MiRNAs are noncoding, 21-24 nucleotide-long RNA particles that control over 60% of genes. MiRNAs affect gene expression through binding to the 3'-untranslated region of messenger RNA (mRNA), thus inhibiting mRNA translation or inducing mRNA degradation. MiRNAs have been associated with various cardiovascular diseases, including heart failure, hypertension, left ventricular hypertrophy, or ischemic heart disease. In addition, miRNA expression alters during coronary artery bypass grafting (CABG) surgery, which could be used to predict perioperative outcomes. CABG is an operation in which complex coronary arteries stenosis is treated by bypassing atherosclerotic lesions with venous or arterial grafts. Despite a very low perioperative mortality rate and excellent long-term survival, CABG is associated with postoperative complications, including reperfusion injury, graft failure, atrial fibrillation and perioperative myocardial infarction. So far, no reliable diagnostic and prognostic tools to predict prognosis after CABG have been developed. Changes in the perioperative miRNA expression levels could improve the diagnosis of post-CABG myocardial infarction and atrial fibrillation and could be used to stratify risk after CABG. Herein, we describe the expression changes of different subtypes of miRNAs during CABG and review the diagnostic and prognostic utility of miRNAs in patients undergoing CABG.

Contribution of platelet-derived microRNAs to serum microRNAs in healthy men

Platelets are a major source of microRNAs (miRNAs) in blood. Relationships between circulating platelet-derived miRNAs were investigated to elucidate their significance as biomarkers. Total miRNAs in serum were analyzed using the 3D-Gene miRNA Oligo chip. Among 22 miRNAs that are included in platelets and play functional roles, sufficient miRNA levels for comparison were detected for 11 miRNAs (let-7b-5p, miR-16-5p, miR-17-5p, miR-24-3p, miR-107, miR-126-3p, miR-150-3p, miR-191-5p, miR-197-3p, miR-223-3p, and miR-326). Among 55 pairs prepared by these miRNAs, relatively strong correlations (Spearman's correlation coefficient >0.8) were shown between miRNAs of 7 pairs including let-7b-5p and miR-16-5p, let-7b-5p and miR-17-5p, let-7b-5p and miR-107, miR-16-5p and miR-17-5p, miR-16-5p and miR-107, miR-17-5p and miR-107, and miR-107 and miR-126-3p. In principal component analysis, the first principal component consisted of let-7b-5p, miR-16-5p, miR-17-5p, miR-107, miR-126-3p, and miR-191-5p. These six miRNAs may be useful biomarkers that reflect platelet condition and function.

MiR-126-3p Is Dynamically Regulated in Endothelial-to-Mesenchymal Transition during Fibrosis

In fibrotic diseases, myofibroblasts derive from a range of cell types including endothelial-to-mesenchymal transition (EndMT). Increasing evidence suggests that miRNAs are key regulators in biological processes but their profile is relatively understudied in EndMT. In human umbilical vein endothelial cells (HUVEC), EndMT was induced by treatment with TGFβ2 and IL1β. A significant decrease in endothelial markers such as VE-cadherin, CD31 and an increase in mesenchymal markers such as fibronectin were observed. In parallel, miRNA profiling showed that miR-126-3p was down-regulated in HUVECs undergoing EndMT and over-expression of miR-126-3p prevented EndMT, maintaining CD31 and repressing fibronectin expression. EndMT was investigated using lineage tracing with transgenic Cdh5-Cre-ERT2; Rosa26R-stop-YFP mice in two established models of fibrosis: cardiac ischaemic injury and kidney ureteric occlusion. In both cardiac and kidney fibrosis, lineage tracing showed a significant subpopulation of endothelial-derived cells expressed mesenchymal markers, indicating they had undergone EndMT. In addition, miR-126-3p was restricted to endothelial cells and down-regulated in murine fibrotic kidney and heart tissue. These findings were confirmed in patient kidney biopsies. MiR-126-3p expression is restricted to endothelial cells and is down-regulated during EndMT. Over-expression of miR-126-3p reduces EndMT, therefore, it could be considered for miRNA-based therapeutics in fibrotic organs.

miR-126-3p is essential for CXCL12-induced angiogenesis

Atherosclerosis, in the ultimate stage of cardiovascular diseases, causes an obstruction of vessels leading to ischemia and finally to necrosis. To restore vascularization and tissue regeneration, stimulation of angiogenesis is necessary. Chemokines and microRNAs (miR) were studied as pro-angiogenic agents. We analysed the miR-126/CXCL12 axis and compared impacts of both miR-126-3p and miR-126-5p strands effects in CXCL12-induced angiogenesis. Indeed, the two strands of miR-126 were previously shown to be active but were never compared together in the same experimental conditions regarding their differential functions in angiogenesis. In this study, we analysed the 2D-angiogenesis and the migration assays in HUVEC in vitro and in rat's aortic rings ex vivo, both transfected with premiR-126-3p/-5p or antimiR-126-3p/-5p strands and stimulated with CXCL12. First, we showed that CXCL12 had pro-angiogenic effects in vitro and ex vivo associated with overexpression of miR-126-3p in HUVEC and rat's aortas. Second, we showed that 2D-angiogenesis and migration induced by CXCL12 was abolished in vitro and ex vivo after miR-126-3p inhibition. Finally, we observed that SPRED-1 (one of miR-126-3p targets) was inhibited after CXCL12 treatment in HUVEC leading to improvement of CXCL12 pro-angiogenic potential in vitro. Our results proved for the first time: 1-the role of CXCL12 in modulation of miR-126 expression; 2-the involvement of miR-126 in CXCL12 pro-angiogenic effects; 3-the involvement of SPRED-1 in angiogenesis induced by miR-126/CXCL12 axis.

The role of extracellular vesicles in neointima formation post vascular injury

Pathological neointimal growth can develop in patients as a result of vascular injury following percutaneous coronary intervention and coronary artery bypass grafting using autologous saphenous vein, leading to arterial or vein graft occlusion. Neointima formation driven by intimal hyperplasia occurs as a result of a complex interplay between molecular and cellular processes involving different cell types including endothelial cells, vascular smooth muscle cells and various inflammatory cells. Therefore, understanding the intercellular communication mechanisms underlying this process remains of fundamental importance in order to develop therapeutic strategies to preserve endothelial integrity and vascular health post coronary interventions. Extracellular vesicles (EVs), including microvesicles and exosomes, are membrane-bound particles secreted by cells which mediate intercellular signalling in physiological and pathophysiological states, however their role in neointima formation is not fully understood. The purification and characterization techniques currently used in the field are associated with many limitations which significantly hinder the ability to comprehensively study the role of specific EV types and make direct functional comparisons between EV subpopulations. In this review, the current knowledge focusing on EV signalling in neointima formation post vascular injury is discussed.

miRNA-126-3p carried by human umbilical cord mesenchymal stem cell enhances endothelial function through exosome-mediated mechanisms in vitro and attenuates vein graft neointimal formation in vivo

BACKGROUND

The aim of this study was to determine whether the combination of MSC implantation with miRNA-126-3p overexpression would further improve the surgical results after vein grafting.

METHODS

human umbilical cord MSCs (hucMSCs) and human umbilical vein endothelial cells (HUVECs) were isolated from human umbilical cords and characterized by a series of experiments. Lentivirus vector encoding miRNA-126-3p was transfected into hucMSCs and verified by PCR. We analyzed the miRNA-126-3p-hucMSC function in vascular endothelial cells by using a series of co-culture experiments. miRNA-126-3p-hucMSCs-exosomes were separated from cell culture supernatants and identified by WB and TEM. We validated the role of miRNA-126-3p-hucMSCs-exosomes on HUVECs proliferative and migratory and angiogenic activities by using a series of function experiments. We further performed co-culture experiments to detect downstream target genes and signaling pathways of miRNA-126-3p-hucMSCs in HUVECs. We established a rat vein grafting model, CM-Dil-labeled hucMSCs were injected intravenously into rats, and the transplanted cells homing to the vein grafts were detected by fluorescent microscopy. We performed historical and immunohistochemical experiments to exam miRNA-126-3p-hucMSC transplantation on vein graft neointimal formation and reendothelialization in vitro.

RESULTS

We successfully isolated and identified primary hucMSCs and HUVECs. Primary hucMSCs were transfected with lentiviral vectors carrying miRNA-126-3p at a MOI 75. Co-culture studies indicated that overexpression of miRNA-126-3p in hucMSCs enhanced HUVECs proliferation, migration, and tube formation in vivo. We successfully separated hucMSCs-exosomes and found that miRNA-126-3p-hucMSCs-exosomes can strengthen the proliferative, migratory, and tube formation capacities of HUVECs. Further PCR and WB analysis indicated that, SPRED-1/PIK3R2/AKT/ERK1/2 pathways are involved in this process. In the rat vein arterialization model, reendothelialization analysis showed that transplantation with hucMSCs modified with miRNA-126-3p had a higher reendothelialization of the vein grafts. The subsequent historical and immunohistochemical examination revealed that delivery with miRNA-126-3p overexpressed hucMSCs significantly reduced vein graft intimal hyperplasia in rats.

CONCLUSION

These results suggest hucMSC-based miRNA-126-3p gene therapy may be a novel option for the treatment of vein graft disease after CABG.

Differentially Expressed MicroRNAs Associated with Vein Graft Restenosis in Rats

Objective: Intimal hyperplasia is the main cause of restenosis of vein grafts after venous transplantation. MicroRNAs are considered to play a role in vein graft restenosis; however, the expression profile of microRNAs in neointima has not been reported in detail. We wanted to investigate the differentially expressed microRNAs in the restenosis of vein grafts in rats.Methods: We established a rat model for vein transplantation to explore the pathogenic roles of microRNAs during intimal hyperplasia. Hematoxylin and eosin staining was used to confirm intimal hyperplasia in the vein grafts. Changes in microRNA expression in the vein grafts were detected 3 and 14 days after surgery by sequencing, reverse transcription‐quantitative polymerase chain reaction, and bioinformatics analyses for functional annotation.Results: We detected 711 newly predicted microRNAs among all the comparisons. Among these comparisons, 437 differentially expressed microRNAs were detected in the postoperative day 3 group versus the control group, 265 were detected in the postoperative day 14 group versus the control group, and 158 were detected in the postoperative day 14 group versus the postoperative day 3 group. Pathway analysis revealed significant enrichment of target genes that mediate Wnt, mitogen-activated protein kinase, vascular smooth muscle contraction, and regulation of actin cytoskeleton signaling.Conclusion: Our results provide insight into the pathogenesis of restenosis and will help develop novel targets in the prevention and treatment of vein graft restenosis.

The State of Art of Regenerative Therapy in Cardiovascular Ischemic Disease: Biology, Signaling Pathways, and Epigenetics of Endothelial Progenitor Cells

Ischemic heart disease is currently a major cause of mortality and morbidity worldwide. Nevertheless, the actual therapeutic scenario does not target myocardial cell regeneration and consequently, the progression toward the late stage of chronic heart failure is common. Endothelial progenitor cells (EPCs) are bone marrow-derived stem cells that contribute to the homeostasis of the endothelial wall in acute and chronic ischemic disease. Calcium modulation and other molecular pathways (NOTCH, VEGFR, and CXCR4) contribute to EPC proliferation and differentiation. The present review provides a summary of EPC biology with a particular focus on the regulatory pathways of EPCs and describes promising applications for cardiovascular cell therapy.

Application of tissue-engineered interventions for coronary artery bypass grafts

Coronary artery bypass graft is one of the extensively conducted procedures to release occlusion in the coronary vessel. Various biological grafts are used for this purpose, superiorly, saphenous vein graft, if unavailable, other vessels in the body, with likewise characteristics are exploited for the purpose. The choice of graft is yet under discovery that could impeccably meet all the requirements. Variation in perioperative and postoperative results have given uneven clinical inferences of these conduits. Alternatively, tissue-engineering is also being applied in this area for clinical improvements. This review underlines some of the commonly used grafts for coronary artery bypass graft and advancements in tissue engineering for this purpose.

Exosomes derived from human umbilical cord mesenchymal stem cells inhibit vein graft intimal hyperplasia and accelerate reendothelialization by enhancing endothelial function

Background

In our previous research, we found that mesenchymal stem cell (MSC) transplantation therapy can inhibit intimal hyperplasia and enhance endothelial function in arterialized vein grafts in rats. However, whether MSC-derived exosomes (MSC-exosomes) can reduce neointimal formation and its possible mechanism is still unclear.

Methods

The primary human umbilical cord MSCs (hucMSCs) and human umbilical vein endothelial cells (HUVECs) were isolated and characterized by flow cytometry and immunofluorescence. The exosomes derived from hucMSCs (hucMSC-exosomes) were identified by transmission electron microscopy and western blots. hucMSC-exosomes were intravenously injected into a rat model of vein grafting, and its effect on vein grafts reendothelialization and intimal hyperplasia was assessed by physical, histological, immunohistochemistry, and immunofluorescence examinations. The effects of hucMSC-exosomes on endothelial cells were evaluated by integrated experiment, EdU staining, scratch assay, and Transwell assay. The expression levels of key gene and pathways associated with the biological activity of vascular endothelial cells were evaluated following the stimulation of hucMSC-exosomes.

Results

We successfully isolated and characterized primary hucMSCs and hucMSC-exosomes and primary HUVECs. We verified that the systemic administration of hucMSC-exosomes accelerates reendothelialization and decreases intimal hyperplasia of autologous vein graft in a rat model. We also identified that hucMSC-exosomes can be uptaken by endothelial cells to stimulate cell proliferative and migratory activity in vitro. Furthermore, we detected that vascular endothelial growth factor (VEGF) plays an important part in hucMSC-exosome-mediated proliferation and migration in HUVECs. In addition, we also provided evidence that the signalling pathways of PI3K/AKT and MAPK/ERK1/2 take part in hucMSC-exosome-induced VEGF regulation.

Conclusion

Our data suggest that hucMSC-exosomes exert a vasculoprotective role in the setting of vein graft disease, which may provide a new clue to protect against vein graft failure in the future.

Circulating exosomes from patients with peripheral artery disease influence vascular cell migration and contain distinct microRNA cargo

Objective

Peripheral artery disease (PAD) is a chronic condition characterized by inflammation. Emerging literature suggests that circulating exosomes and their microRNA (miRNA) contents may influence atherosclerosis and vascular remodeling. We hypothesize that circulating exosomes in patients with PAD directly modulate vascular cell phenotype and contain proinflammatory miRNAs.

Methods

Exosomes (particle size, 30-150 nm) were isolated from plasma of healthy individuals (n = 6), patients with mild PAD (mPAD; median Rutherford class, 2.5; n = 6), and patients with severe PAD (sPAD; median Rutherford class, 4; n = 5). Exosome identity, size, and concentration were determined by Western blot and nanoparticle tracking analysis. Human vascular smooth muscle cell (VSMC) and endothelial cell (EC) migration was assessed by a standard wound closure assay after exposure to exosome preparations. Monocyte-derived macrophages isolated from healthy volunteers were exposed to exosome preparations, and targeted gene expression was analyzed using quantitative polymerase chain reaction. Exosome miRNA cargos were isolated, and a panel of defined, vascular-active miRNAs was assessed by quantitative polymerase chain reaction.

Results

There was no difference in overall exosome particle concentration or size between the three groups (one-way analysis of variance [ANOVA], P > .05). Compared with exosomes from healthy individuals, exosomes from mPAD and sPAD patients increased VSMC migration (1.0 ± 0.09-fold vs 1.5 ± 0.09-fold vs 2.0 ± 0.12-fold wound closure; ANOVA, P < .0001) and inhibited EC migration (1.8 ± 0.07-fold vs 1.5 ± 0.04-fold vs 1.3 ± 0.02-fold wound closure; ANOVA, P < .01) in a stepwise fashion. Exosomes also induced changes in monocyte-derived macrophage gene expression that did not appear PAD specific. Hierarchical analysis of exosome miRNA revealed distinct clustering of vascular-active miRNAs between the three groups. Several miRNAs that promote inflammatory pathways in vascular cells were expressed at higher levels in exosomes from sPAD patients.

Conclusions

Circulating exosomes from individuals with PAD exert in vitro functional effects on VSMCs and ECs that may promote adverse vessel remodeling. Exosomes from healthy individuals, mPAD patients, and sPAD patients contain distinct signatures of immune-regulatory miRNA. Together these data suggest that the proinflammatory cargo of circulating exosomes correlates with atherosclerosis severity in PAD patients and could influence vascular injury and repair.

Exosomes and their cargo have been implicated in several vascular remodeling processes including atherosclerosis, angiogenesis, and neointimal hyperplasia. In this study, we demonstrate that circulating exosomes from individuals with peripheral artery disease exert in vitro effects on vascular cells that may adversely affect vessel remodeling. Moreover, these exosomes contain elevated levels of vascular-active microRNA. Our results suggest that exosomes may serve as both biomarkers and effectors of vascular disease in patients with peripheral artery disease and motivate further investigation into the role of exosomes and their contents in aberrant remodeling in vascular diseases.

Upregulation of miR‑423 improves autologous vein graft restenosis via targeting ADAMTS‑7

Coronary artery bypass graft (CABG) is one of the primary methods of treating coronary heart disease (CHD); however, vein graft restenosis is a major limiting factor of the effectiveness of CABG. Emerging evidence has indicated that miR‑423 is associated with vascular diseases. Additionally, upregulation of a disintegrin and metalloproteinase with thrombospondin motifs‑7 (ADAMTS‑7) contributes to neointima formation by promoting the proliferation and migration of vascular smooth muscle cells and inhibiting the proliferation and migration of endothelial cells. The aim of the present study was to examine the effects of miR‑423 target, ADAMTS‑7, on regulating vein graft disease and identify novel biomarkers for use in therapy of vein graft failure (VGF). Aberrant expression of miR‑423 in plasma of patients with CHD prior to and following CABG confirms that miR‑423 may be a suitable target for preventing VGF. Furthermore, a dual‑luciferase reporter gene assay indicated that miR‑423 directly interacted with ADAMTS‑7 and suppressed its expression. Ectopic expression of miR‑423 suppressed ADAMTS‑7, resulting in decreased proliferation and migration rates of human umbilical vein smooth muscle cells by targeting ADAMTS‑7, but resulted in increased proliferation and migration of human umbilical vein endothelial cells in vitro. Overexpression of miR‑423 also enhanced re‑endothelialization and decreased neointimal formation in a rat vein graft model. In conclusion, the results of the present study demonstrated that the miR‑423/ADAMTS‑7 axis may possess potential clinical value for the prevention and treatment of restenosis in patients with CHD following CABG.