Platelet-derived miR-223 promotes a phenotypic switch in arterial injury repair

MicroRNAs in diabetic macroangiopathy

Diabetic macroangiopathy is a leading cause of diabetes-related mortality worldwide. Both genetic and environmental factors, through a multitude of underlying molecular mechanisms, contribute to the pathogenesis of diabetic macroangiopathy. MicroRNAs (miRNAs), a class of non-coding RNAs known for their functional diversity and expression specificity, are increasingly recognized for their roles in the initiation and progression of diabetes and diabetic macroangiopathy. In this review, we will describe the biogenesis of miRNAs, and summarize their functions in diabetic macroangiopathy, including atherosclerosis, peripheral artery disease, coronary artery disease, and cerebrovascular disease, which are anticipated to provide new insights into future perspectives of miRNAs in basic, translational and clinical research, ultimately advancing the diagnosis, prevention, and treatment of diabetic macroangiopathy.

Lung megakaryocytes engulf inhaled airborne particles to promote intrapulmonary inflammation and extrapulmonary distribution

Many lung immune cells are known to respond to inhaled particulate matter. However, current known responses cannot explain how particles induce thrombosis in the lung and how they translocate to distant organs. Here, we demonstrate that lung megakaryocytes (MKs) in the alveolar and interstitial regions display location-determined characteristics and act as crucial responders to inhaled particles. They move rapidly to engulf particles and become activated with upregulation in inflammatory responses and thrombopoiesis. Comprehensive in vivo, in vitro and ex vivo results unraveled that MKs were involved in particle-induced lung damages and shed particle-containing platelets into blood circulation. Moreover, MK-derived platelets exhibited faster clotting, stronger adhesion than normal resting platelets, and inherited the engulfed particles from parent MKs to assist in extrapulmonary particle transportation. Our findings collectively highlight that the specific responses of MKs towards inhaled particles and their roles in facilitating the translocation of particles from the lungs to extrapulmonary organs for clearance.

Early thrombus formation is required for eccentric and heterogeneous neointimal hyperplasia under disturbed flow

BACKGROUND

Anticoagulation and antiplatelet therapy effectively inhibit neointimal hyperplasia (NIH) in both arterial and venous systems but not in arteriovenous fistulae (AVF). The main site of AVF failure is the juxta-anastomotic area that is characterized by disturbed flow compared with laminar flow in the arterial inflow and the venous outflow.

OBJECTIVES

We hypothesized that early thrombus formation is required for eccentric and heterogeneous NIH in the presence of disturbed flow.

METHODS

Needle puncture and sutured AVF were created in C57BL/6 mice, in PF4-Cre × mT/mG reporter mice, and in Wistar rats. Human AVF samples were second-stage basilic vein transpositions. The tissues were examined by histology, immunofluorescence, immunohistochemistry, and en face staining.

RESULTS

In the presence of disturbed flow, both mouse and human AVF showed eccentric and heterogeneous NIH. Maladapted vein wall was characterized by eccentric and heterogeneous neointima that was composed of a different abundance of thrombus and smooth muscle cells. PF4-cre × mT/mG reporter mice AVF showed that green fluorescent protein-labeled platelets deposit on the wall directly facing the fistula exit with endothelial cell loss and continue to accumulate in the presence of disturbed flow. Neither disturbed flow with limited endothelial cell loss nor nondisturbed flow induced heterogeneous neointima in different animal models.

CONCLUSION

Early thrombus contributes to late heterogeneous NIH in the presence of disturbed flow. Disturbed flow, large area of endothelial cell loss, and thrombus formation are critical to form eccentric and heterogeneous NIH. Categorization of adapted or maladapted walls may be helpful for therapy targeting heterogeneous NIH.

Circ_0090231 knockdown protects vascular smooth muscle cells from ox-LDL-induced proliferation, migration and invasion via miR-942-5p/PPM1B axis during atherosclerosis

Atherosclerosis (AS) is a dominant pathological basis of cardiovascular disease. Circular RNAs (circRNAs) have been proposed to have crucial functions in regulating pathological progressions of AS. Hence, the aim of this study was to investigate the potential function of circ_0090231 in AS progression. Oxidized low densitylipoprotein (ox-LDL)-challenged vascular smooth muscle cells (VSMCs) were used for in vitro functional analysis. Levels of genes and proteins were measured by qRT-PCR and Western blot. The proliferation, migration and invasion were assessed using cell counting kit-8, 5-ethynyl-2'-deoxyuridine, and transwell assays. The interaction between miR-942-5p and circ_0090231 or PPM1B (Protein Phosphatase, Mg2+/Mn2+ Dependent 1B) was evaluated by dual-luciferase reporter and pull-down assays. Circ_0090231 is a stable circRNA, and was increased in the serum of AS patients and ox-LDL-challenged VSMCs. Functionally, silencing of circ_0090231 could reverse ox-LDL-induced proliferation, migration and invasion in VSMCs. Mechanistically, circ_0090231 directly targeted miR-942-5p, and PPM1B was a target of miR-942-5p. Besides, circ_0090231 sequestered miR-942-5p to release PPM1B expression, suggesting the circ_0090231/miR-942-5p/PPM1B axis. Further rescue experiments showed that miR-942-5p inhibition or ectopic overexpression of PPM1B dramatically attenuated the suppressing influences of circ_0090231 knockdown on VSMC proliferative, migratory and invasive abilities under ox-LDL treatment. Silencing of circ_0090231 could reverse ox-LDL-induced proliferation, migration and invasion in VSMCs via miR-942-5p/PPM1B axis, providing a theoretical basis for elucidating the mechanism of AS process.

Exosomes derived from induced cardiopulmonary progenitor cells alleviate acute lung injury in mice

Cardiopulmonary progenitor cells (CPPs) constitute a minor subpopulation of cells that are commonly associated with heart and lung morphogenesis during embryonic development but completely subside after birth. This fact offers the possibility for the treatment of pulmonary heart disease (PHD), in which the lung and heart are both damaged. A reliable source of CPPs is urgently needed. In this study, we reprogrammed human cardiac fibroblasts (HCFs) into CPP-like cells (or induced CPPs, iCPPs) and evaluated the therapeutic potential of iCPP-derived exosomes for acute lung injury (ALI). iCPPs were created in passage 3 primary HCFs by overexpressing GLI1, WNT2, ISL1 and TBX5 (GWIT). Exosomes were isolated from the culture medium of passage 6-8 GWIT-iCPPs. A mouse ALI model was established by intratracheal instillation of LPS. Four hours after LPS instillation, ALI mice were treated with GWIT-iCPP-derived exosomes (5 × 109, 5 × 1010 particles/mL) via intratracheal instillation. We showed that GWIT-iCPPs could differentiate into cell lineages, such as cardiomyocyte-like cells, endothelial cells, smooth muscle cells and alveolar epithelial cells, in vitro. Transcription analysis revealed that GWIT-iCPPs have potential for heart and lung development. Intratracheal instillation of iCPP-derived exosomes dose-dependently alleviated LPS-induced ALI in mice by attenuating lung inflammation, promoting endothelial function and restoring capillary endothelial cells and the epithelial cells barrier. This study provides a potential new method for the prevention and treatment of cardiopulmonary injury, especially lung injury, and provides a new cell model for drug screening.

Bergenin alleviates proliferative arterial diseases by modulating glucose metabolism in vascular smooth muscle cells

BACKGROUND

Vascular smooth muscle cell (VSMC) proliferation and phenotypic switching are key mechanisms in the development of proliferative arterial diseases. Notably, reprogramming of the glucose metabolism pattern in VSMCs plays an important role in this process.

PURPOSE

The aim of this study is to investigate the therapeutic potential and the mechanism underlying the effect of bergenin, an active compound found in Bergenia, in proliferative arterial diseases.

METHODS

The effect of bergenin on proliferative arterial disease was evaluated using platelet-derived growth factor (PDGF)-stimulated VSMCs and a mouse model of carotid artery ligation. VSMC proliferation and phenotypic switching were evaluated in vitro using cell counting kit-8, 5-ethynyl-2-deoxyuridine incorporation, scratch, and transwell assays. Carotid artery neointimal hyperplasia was evaluated in vivo using hematoxylin and eosin staining and immunofluorescence. The expression of proliferation and VSMC contractile phenotype markers was evaluated using PCR and western blotting.

RESULTS

Bergenin treatment inhibited PDGF-induced VSMC proliferation and phenotypic switching and reduced neointimal hyperplasia in the carotid artery ligation model. Additionally, bergenin partially reversed the PDGF-induced Warburg-like glucose metabolism pattern in VSMCs. RNA-sequencing data revealed that bergenin treatment significantly upregulated Ndufs2, an essential subunit of mitochondrial complex I. Ndufs2 knockdown attenuated the inhibitory effect of bergenin on PDGF-induced VSMC proliferation and phenotypic switching, and suppressed neointimal hyperplasia in vivo. Conversely, Ndufs2 overexpression enhanced the protective effect of bergenin. Moreover, Ndufs2 knockdown abrogated the effects of bergenin on the regulation of glucose metabolism in VSMCs.

CONCLUSION

These findings suggest that bergenin is effective in alleviating proliferative arterial diseases. The reversal of the Warburg-like glucose metabolism pattern in VSMCs during proliferation and phenotypic switching may underlie this therapeutic mechanism.

High glucose promotes atherosclerosis by regulating miRNA let7d-5p level

BACKGROUND

MiRNA let7d-5p has been recently reported to be abnormally expressed in diabetes-associated atherosclerosis (AS). However, it still remains unknown how let7d-5p contributes to the process of atherosclerosis.

METHODS

Twenty fresh tissues and a total of 28 wax block specimens from carotid endarterectomy procedures were obtained from the Luoyang Central Hospital affiliated to Zhengzhou University. The expression of let7d-5p was assessed using quantitative RT-PCR (qRT-PCR). A series of in vitro experiments was used to determine the roles of let7d-5p knockdown and overexpression in vascular smooth muscle cells (VSMCs).

RESULTS

We discovered that the carotid plaques from diabetic patients had lower expression levels of miR let7d-5p. In VSMCs, the expression of miRNA let7d-5p was significantly lower in high glucose conditions compared with low glucose situations. The proliferation and migration of VSMCs were also inhibited by the overexpression of let7d-5p, whereas the opposite was true when let7d-5p was inhibited, according to gain and loss of function studies. Mechanically, let7d-5p might activate the GSK3β/β-catenin signaling pathway via binding to the high mobility group AT-Hook 2 (HMGA2) mRNA in VSMCs. Additionally, GLP-1RA liraglutide may prevent the migration and proliferation of VSMCs by raising let7d-5p levels.

CONCLUSIONS

High glucose stimulated the proliferation and migration of VSMCs by regulating the let7d-5p/HMGA2/GSK3β/β-catenin pathway, and liraglutide may slow atherosclerosis by increasing the levels of miR let7d-5p.

Disturbed flow in the juxta-anastomotic area of an arteriovenous fistula correlates with endothelial loss, acute thrombus formation, and neointimal hyperplasia

Clinical failure of arteriovenous neointimal hyperplasia (NIH) fistulae (AVF) is frequently due to juxta-anastomotic NIH (JANIH). Although the mouse AVF model recapitulates human AVF maturation, previous studies focused on the outflow vein distal to the anastomosis. We hypothesized that the juxta-anastomotic area (JAA) has increased NIH compared with the outflow vein. AVF was created in C57BL/6 mice without or with chronic kidney disease (CKD). Temporal and spatial changes of the JAA were examined using histology and immunofluorescence. Computational techniques were used to model the AVF. RNA-seq and bioinformatic analyses were performed to compare the JAA with the outflow vein. The jugular vein to carotid artery AVF model was created in Wistar rats. The neointima in the JAA shows increased volume compared with the outflow vein. Computational modeling shows an increased volume of disturbed flow at the JAA compared with the outflow vein. Endothelial cells are immediately lost from the wall contralateral to the fistula exit, followed by thrombus formation and JANIH. Gene Ontology (GO) enrichment analysis of the 1,862 differentially expressed genes (DEG) between the JANIH and the outflow vein identified 525 overexpressed genes. The rat jugular vein to carotid artery AVF showed changes similar to the mouse AVF. Disturbed flow through the JAA correlates with rapid endothelial cell loss, thrombus formation, and JANIH; late endothelialization of the JAA channel correlates with late AVF patency. Early thrombus formation in the JAA may influence the later development of JANIH.NEW & NOTEWORTHY Disturbed flow and focal endothelial cell loss in the juxta-anastomotic area of the mouse AVF colocalizes with acute thrombus formation followed by late neointimal hyperplasia. Differential flow patterns between the juxta-anastomotic area and the outflow vein correlate with differential expression of genes regulating coagulation, proliferation, collagen metabolism, and the immune response. The rat jugular vein to carotid artery AVF model shows changes similar to the mouse AVF model.

Non-Coding RNA-Targeted Therapy: A State-of-the-Art Review

The use of non-coding RNAs (ncRNAs) as drug targets is being researched due to their discovery and their role in disease. Targeting ncRNAs, including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), is an attractive approach for treating various diseases, such as cardiovascular disease and cancer. This seminar discusses the current status of ncRNAs as therapeutic targets in different pathological conditions. Regarding miRNA-based drugs, this approach has made significant progress in preclinical and clinical testing for cardiovascular diseases, where the limitations of conventional pharmacotherapy are evident. The challenges of miRNA-based drugs, including specificity, delivery, and tolerability, will be discussed. New approaches to improve their success will be explored. Furthermore, it extensively discusses the potential development of targeted therapies for cardiovascular disease. Finally, this document reports on the recent advances in identifying and characterizing microRNAs, manipulating them, and translating them into clinical applications. It also addresses the challenges and perspectives towards clinical application.

MTMR7 suppresses the phenotypic switching of vascular smooth muscle cell and vascular intimal hyperplasia after injury via regulating p62/mTORC1-mediated glucose metabolism

BACKGROUND AND AIMS

Myotubularin-related protein 7 (MTMR7) suppresses proliferation in various cell types and is associated with cardiovascular and cerebrovascular diseases. However, whether MTMR7 regulates vascular smooth muscle cell (VSMC) and vascular intimal hyperplasia remains unclear. We explored the role of MTMR7 in phenotypic switching of VSMC and vascular intimal hyperplasia after injury.

METHODS AND RESULTS

MTMR7 expression was significantly downregulated in injured arteries. Compared to wild type (WT) mice, Mtmr7-transgenic (Mtmr7-Tg) mice showed reduced intima/media ratio, decreased percentage of Ki-67-positive cells within neointima, and increased Calponin expression in injured artery. In vitro, upregulating MTMR7 by Len-Mtmr7 transfection inhibited platelet derived growth factor (PDGF)-BB-induced proliferation, migration of VSMC and reversed PDGF-BB-induced decrease in expression of Calponin and SM-MHC. Microarray, single cell sequence, and other bioinformatics analysis revealed that MTMR7 is highly related to glucose metabolism and mammalian target of rapamycin complex 1 (mTORC1). Further experiments confirmed that MTMR7 markedly repressed glycolysis and mTORC1 activity in PDGF-BB-challenged VSMC in vitro. Restoring mTORC1 activity abolished MTMR7-mediated suppression of glycolysis, phenotypic shift in VSMC in vitro and protection against vascular intimal hyperplasia in vivo. Furthermore, upregulating MTMR7 in vitro led to dephosphorylation and dissociation of p62 from mTORC1 in VSMC. External expression of p62 in vitro also abrogated the inhibitory effects of MTMR7 on glycolysis and phenotypic switching in PDGF-BB-stimulated VSMC.

CONCLUSIONS

Our study demonstrates that MTMR7 inhibits injury-induced vascular intimal hyperplasia and phenotypic switching of VSMC. Mechanistically, the beneficial effects of MTMR7 are conducted via suppressing p62/mTORC1-mediated glycolysis.

Rosmarinic Acid Activates the Nrf2/ARE Signaling Pathway via the miR-25-3p/SIRT6 Axis to Inhibit Vascular Remodeling

The vital pathological processes in intimal hyperplasia include aberrant vascular smooth muscle cells (VSMCs) proliferation, migration, and phenotypic switching. Rosmarinic acid (RA) is a natural phenolic acid compound. Nevertheless, the underlying mechanism of RA in neointimal hyperplasia is still unclear. Our analysis illustrated that miR-25-3p mimics significantly enhanced PDGF-BB-mediated VSMCs proliferation, migration, and phenotypic switching while RA partially weakened the effect of miR-25-3p. Mechanistically, we found that miR-25-3p directly targets sirtuin (SIRT6). The suppressive effect of the miR-25-3p inhibitor on PDGF-BB-induced VSMCs proliferation, migration, and phenotypic switch was partially eliminated by SIRT6 knockdown. The suppression of the PDGF-BB-stimulated Nrf2/ARE signaling pathway that was activated by the miR-25-3p inhibitor was exacerbated by the SIRT6 knockdown. In in vivo experiments, RA reduced the degree of intimal hyperplasia while miR-25-3p agomir partially reversed the suppressive effect of RA in vascular remodeling. Our results indicate that RA activates the Nrf2/ARE signaling pathway via the miR-25-3p/SIRT6 axis to inhibit vascular remodeling.

MiR-411-5p Promotes Vascular Smooth Muscle Cell Phenotype Switch by Inhibiting Expression of Calmodulin Regulated Spectrin-Associated Protein-1

When stimulated, vascular smooth muscle cells (VSMCs) change from a differentiated to a dedifferentiated phenotype. Dedifferentiated VSMCs have a key activity in cardiovascular diseases such as in-stent restenosis. MicroRNAs (miRNAs) have crucial functions in conversion of differentiated VSMCs to a dedifferentiated phenotype. We investigated the activity of miR-411-5p in the proliferation, migration, and phenotype switch of rat VSMCs.Based on a microRNA array assay, miR-411-5p expression was found to be significantly increased in cultured VSMCs stimulated by platelet-derived growth factor-BB (PDGF-BB). A CCK-8 assay, transwell assay, and scratch test were performed to measure the effect of miR-411-5p on the proliferation and migration of PDGF-BB-treated VSMCs. MiR-411-5p promoted expression of dedifferentiated phenotype markers such as osteopontin and tropomyosin 4 in PDGF-BB-treated VSMCs. Using mimics and inhibitors, we identified the target of miR-411-5p in PDGF-BB-treated VSMCs and found that calmodulin-regulated spectrin-associated protein-1 (CAMSAP1) was involved in the phenotypic switch mediated by PDGF-BB.By inhibiting expression of CAMSAP1, miR-411-5p enhanced the proliferation, migration, and phenotype switch of VSMCs.Blockade of miR-411-5p interaction with CAMSAP1 is a promising approach to treat in-stent restenosis.

Platelet-derived extracellular vesicles aggravate septic acute kidney injury via delivering ARF6

Circulating plasma extracellular vesicles (EVs) mostly originate from platelets and may promote organ dysfunction in sepsis. However, the role of platelet-derived EVs in sepsis-induced acute kidney injury (AKI) remains poorly understood. The present study extracted EVs from the supernatant of human platelets treated with phosphate buffer saline (PBS) or lipopolysaccharide (LPS). Then, we subjected PBS-EVs or LPS-EVs to cecal ligation and puncture (CLP) mice in vivo or LPS-stimulated renal tubular epithelial cells (RTECs) in vitro. Our results indicated that LPS-EVs aggravate septic AKI via promoting apoptosis, inflammation and oxidative stress. Further, ADP-ribosylation factor 6 (ARF6) was identified as a differential protein between PBS-EVs and LPS-EVs by quantitative proteomics analysis. Mechanistically, ARF6 activated ERK/Smad3/p53 signaling to exacerbate sepsis-induced AKI. LPS upregulated ARF6 in RTECs was dependent on TLR4/MyD88 pathway. Both genetically and pharmacologically inhibition of ARF6 attenuated septic AKI. Moreover, platelets were activated by TLR4 and its downstream mediator IKK controlled platelet secretion during sepsis. Inhibition of platelet secretion alleviated septic AKI. Collectively, our study demonstrated that platelet-derived EVs may be a therapeutic target in septic AKI.

The Roles of microRNAs in the Cardiovascular System

The discovery of miRNAs and their role in disease represent a significant breakthrough that has stimulated and propelled research on miRNAs as targets for diagnosis and therapy. Cardiovascular disease is an area where the restrictions of early diagnosis and conventional pharmacotherapy are evident and deserve attention. Therefore, miRNA-based drugs have significant potential for development. Research and its application can make considerable progress, as seen in preclinical and clinical trials. The use of miRNAs is still experimental but has a promising role in diagnosing and predicting a variety of acute coronary syndrome presentations. Its use, either alone or in combination with currently available biomarkers, might be adopted soon, particularly if there is diagnostic ambiguity. In this review, we examine the current understanding of miRNAs as possible targets for diagnosis and treatment in the cardiovascular system. We report on recent advances in recognising and characterising miRNAs with a focus on clinical translation. The latest challenges and perspectives towards clinical application are discussed.

Dipyridamole and vascular healing following stent implantation

Introduction

Patients undergoing coronary stent implantation incur a 2% annual rate of adverse events, largely driven by in-stent restenosis (ISR) due to neointimal (NI) tissue proliferation, a process in which smooth muscle cell (SMC) biology may play a central role. Dipyridamole (DP) is an approved therapeutic agent with data supporting improved vascular patency rates. Pre-clinical data supports that DP may enact its vasculoprotective effects via adenosine receptor-A2B (ADOR-A2B). We sought to evaluate the efficacy of DP to mitigate ISR in a pre-clinical rabbit stent model.

Methods & Results

24 New Zealand White Rabbits were divided into two cohorts-non-atherosclerosis and atherosclerosis (n = 12/cohort, 6 male and 6 female). Following stent implantation, rabbits were randomized 1:1 to control or oral dipyridamole therapy for 6 weeks followed by optical coherence tomography (OCT) and histology assessment of NI burden and stent strut healing. Compared to control, DP demonstrated a 16.6% relative reduction in NI volume (14.7 ± 0.8% vs. 12.5 ± 0.4%, p = 0.03) and a 36.2% relative increase in optimally healed stent struts (37.8 ± 2.8% vs. 54.6 ± 2.5%, p < 0.0001). Atherosclerosis demonstrated attenuated effect with no difference in NI burden (15.2 ± 1.0% vs. 16.9 ± 0.8%, p = 0.22) and only a 14.2% relative increase in strut healing (68.3 ± 4.1% vs. 78.7 ± 2.5%, p = 0.02). DP treated rabbits had a 44.6% (p = 0.045) relative reduction in NI SMC content. In vitro assessment of DP and coronary artery SMCs yielded dose-dependent reduction in SMC migration and proliferation. Selective small molecule antagonism of ADOR-A2B abrogated the effects of DP on SMC proliferation. DP modulated SMC phenotypic switching with ADOR-A2B siRNA knockdown supporting its role in the observed effects.

Conclusion

Dipyridamole reduces NI proliferation and improves stent healing in a preclinical model of stent implantation with conventional antiplatelets. Atherosclerosis attenuates the observed effect. Clinical trials of DP as an adjunctive agent may be warranted to evaluate for clinical efficacy in stent outcomes.

The downstream network of STAT6 in promoting vascular smooth muscle cell phenotypic switch and neointimal formation

Intimal thickening caused by the excessive multiplication of vascular smooth muscle cells (VSMCs) is the pathological process central to cardiovascular diseases, including restenosis. In response to vascular injury, VSMCs would undergo phenotypic switching from a fully differentiated, low proliferative rate phenotype to a more pro-proliferative, promigratory, and incompletely-differentiated state. The lack of a full understanding of the molecular pathways coupling the vascular injury stimuli to VSMCs phenotype switching largely limits the development of medical therapies for treating intima hyperplasia-related diseases. The role of signal transducers and activators of transcription 6 (STAT6) in modulating the proliferation and differentiation of various cell types, especially macrophage, has been well investigated, but little is known about its pathophysiological role and target genes in restenosis after vascular injury. In the present work, Stat6-/- mice were observed to exhibit less severe intimal hyperplasia compared with Stat6+/+ mice after carotid injury. The expression of STAT6 was upregulated in VSMCs located in the injured vascular walls. STAT6 deletion leads to decreased proliferation and migration of VSMCs while STAT6 overexpression enhances the proliferation and migration of VSMCs companies with reduced expression of VSMCs marker genes and organized stress fibers. The effect of STAT6 in mouse VSMCs was conserved in human aortic SMCs. RNA-deep-sequencing and experiments verification revealed LncRNA C7orf69/LOC100996318-miR-370-3p/FOXO1-ER stress signaling as the downstream network mediating the pro-dedifferentiation effect of STAT6 in VSMCs. These findings broaden our understanding of vascular pathological molecules and throw a beam of light on the therapy of a variety of proliferative vascular diseases.

Platelet Membrane-Fused Circulating Extracellular Vesicles Protect the Heart from Ischemia/Reperfusion Injury

Myocardial ischemia/reperfusion injury (I/RI) may potentiate cardiac remodeling and heart failure, while effective therapies for I/RI remain lacking. Circulating human plasma-derived extracellular vesicles (hEV) have great potential to protect against I/RI. However, the effective delivery of hEV in vivo remains a limiting factor for clinical application. The present study constructs a biomimetic delivery system of platelet membrane-fused hEV (P-hEV), utilizing the natural affinity of platelets for hEV delivery to the injured vascular and myocardial sites. The results show that platelet membrane and hEV membrane fusion can be achieved through repeated extrusion. Compared to non-modified hEV, P-hEV uptake is greatly enhanced in human umbilical vein endothelial cells (HUVECs) stressed by oxygen-glucose deprivation/reperfusion (OGD/R). Functionally, P-hEV inhibits HUVEC and neonatal rat cardiomyocyte (NRCM) apoptosis and promotes HUVECs migration and tube formation under OGD/R stress in vitro. Intravenous delivery of P-hEV more effectively targets and accumulates at injury sites in the heart. Furthermore, P-hEV significantly enhances protection against acute I/RI and attenuates cardiac remodeling at three weeks post-I/RI. In conclusion, the platelet membrane-fused hEV delivery system enhances the target delivery of EV to protect against myocardial I/RI, presenting a novel drug delivery system for ischemic heart diseases.

PBMC MicroRNAs: Promising Biomarkers for the Differential Diagnosis of COVID-19 Patients with Abnormal Coagulation Indices

MicroRNAs, or miRNAs, may involve in coagulation and inflammation pathways caused by severe Coronavirus disease (COVID-19). Accordingly, this attempt was made to explore the behavior of peripheral blood mononuclear cells (PBMCs) miRNAs as effective biomarkers to diagnose COVID-19 patients with normal and abnormal coagulation indices. We selected the targeted miRNAs (miR-19a-3p, miR-223-3p, miR-143-5p, miR-494-3p and miR-301a-5p) according to previous reports, whose PBMC levels were then determined by real-time PCR. Receiver operating characteristic (ROC) curve was obtained to clarify the diagnostic potency of studied miRNAs. The differentially expressed miRNA profiles and corresponding biological activities were predicted in accordance with bioinformatics data. Targeted miRNAs' expression profiles displayed a significant difference between COVID-19 subjects with normal and abnormal coagulation indices. Moreover, the average miR-223-3p level expressed in COVID-19 cases with normal coagulation indices was significantly lower than that in healthy controls. Based on data from ROC analysis, miR-223-3p and miR-494-3p are promising biomarkers to distinguish the COVID-19 cases with normal or abnormal coagulation indices. Bioinformatics data highlighted the prominent role of selected miRNAs in the inflammation and TGF-beta signaling pathway. The differences existed in the expression profiles of selected miRNAs between the groups introduced miR-494-3p and miR-223-3p as potent biomarkers to prognosis the incidence of COVID-19.

The Role of TGF-β Signaling in Saphenous Vein Graft Failure after Peripheral Arterial Disease Bypass Surgery

Saphenous vein bypass grafting is an effective technique used to treat peripheral arterial disease (PAD). However, restenosis is the major clinical challenge for the graft vessel among people with PAD postoperation. We hypothesize that there is a common culprit behind arterial occlusion and graft restenosis. To investigate this hypothesis, we found TGF-β, a gene specifically upregulated in PAD arteries, by bioinformatics analysis. TGF-β has a wide range of biological activities and plays an important role in vascular remodeling. We discuss the molecular pathway of TGF-β and elucidate its mechanism in vascular remodeling and intimal hyperplasia, including EMT, extracellular matrix deposition, and fibrosis, which are the important pathways contributing to stenosis. Additionally, we present a case report of a patient with graft restenosis linked to the TGF-β pathway. Finally, we discuss the potential applications of targeting the TGF-β pathway in the clinic to improve the long-term patency of vein grafts.

MicroRNA regulation of phenotypic transformations in vascular smooth muscle: relevance to vascular remodeling

Alterations in the vascular smooth muscle cells (VSMC) phenotype play a critical role in the pathogenesis of several cardiovascular diseases, including hypertension, atherosclerosis, and restenosis after angioplasty. MicroRNAs (miRNAs) are a class of endogenous noncoding RNAs (approximately 19-25 nucleotides in length) that function as regulators in various physiological and pathophysiological events. Recent studies have suggested that aberrant miRNAs' expression might underlie VSMC phenotypic transformation, appearing to regulate the phenotypic transformations of VSMCs by targeting specific genes that either participate in the maintenance of the contractile phenotype or contribute to the transformation to alternate phenotypes, and affecting atherosclerosis, hypertension, and coronary artery disease by altering VSMC proliferation, migration, differentiation, inflammation, calcification, oxidative stress, and apoptosis, suggesting an important regulatory role in vascular remodeling for maintaining vascular homeostasis. This review outlines recent progress in the discovery of miRNAs and elucidation of their mechanisms of action and functions in VSMC phenotypic regulation. Importantly, as the literature supports roles for miRNAs in modulating vascular remodeling and for maintaining vascular homeostasis, this area of research will likely provide new insights into clinical diagnosis and prognosis and ultimately facilitate the identification of novel therapeutic targets.

Glycolysis and de novo fatty acid synthesis cooperatively regulate pathological vascular smooth muscle cell phenotypic switching and neointimal hyperplasia

Switching of vascular smooth muscle cells (VSMCs) from a contractile phenotype to a dedifferentiated (proliferative) phenotype contributes to neointima formation, which has been demonstrated to possess a tumor-like nature. Dysregulated glucose and lipid metabolism is recognized as a hallmark of tumors but has not thoroughly been elucidated in neointima formation. Here, we investigated the cooperative role of glycolysis and fatty acid synthesis in vascular injury-induced VSMC dedifferentiation and neointima formation. We found that the expression of hypoxia-inducible factor-1α (HIF-1α) and its target 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3), a critical glycolytic enzyme, were induced in the neointimal VSMCs of human stenotic carotid arteries and wire-injured mouse carotid arteries. HIF-1α overexpression led to elevated glycolysis and resulted in a decreased contractile phenotype while promoting VSMC proliferation and activation of the mechanistic target of rapamycin complex 1 (mTORC1). Conversely, silencing Pfkfb3 had the opposite effects. Mechanistic studies demonstrated that glycolysis generates acetyl coenzyme A to fuel de novo fatty acid synthesis and mTORC1 activation. Whole-transcriptome sequencing analysis confirmed the increased expression of PFKFB3 and fatty acid synthetase (FASN) in dedifferentiated VSMCs. More importantly, FASN upregulation was observed in neointimal VSMCs of human stenotic carotid arteries. Finally, interfering with PFKFB3 or FASN suppressed vascular injury-induced mTORC1 activation, VSMC dedifferentiation, and neointima formation. Together, this study demonstrated that PFKFB3-mediated glycolytic reprogramming and FASN-mediated lipid metabolic reprogramming are distinctive features of VSMC phenotypic switching and could be potential therapeutic targets for treating vascular diseases with neointima formation. © 2023 The Pathological Society of Great Britain and Ireland.

A double-edged sword of platelet-derived extracellular vesicles in tissues, injury or repair: The current research overview

Extracellular vesicles (EVs) are vesicular bodies with a double-layered membrane structure that are detached from the cell membrane or secreted by the cells. EVs secreted by platelets account for the main part in the blood circulation, which account for about 30% or even more. Many types of cells are regulated by PEVs, including endothelial cells, leukocytes, smooth muscle cells, etc. Nevertheless, despite the growing interest in the study of extracellular vesicles, there are still only a few studies on the role of PEVs. Therefore, this overview mainly focuses on one method of isolation and the functions of PEVs in tissues found so far, including promoting tissue repair and mediating tissue damage, which can be used for researchers to continue to explore the role of PEVs in other fields.

Thymic stromal lymphopoietin induces platelet mitophagy and promotes thrombosis in Kawasaki disease

Kawasaki disease (KD) is an acute systemic vasculitis primarily affecting infants and children. Activated platelets predispose patients to coronary artery structural lesions that may lead to thrombotic cardiovascular events. To discover potential proteins underlying platelet activation in KD, we conducted a protein chip assay of 34 cytokines and discovered thymic stromal lymphopoietin (TSLP) was aberrantly expressed, which remained elevated after intravenous immunoglobulin G (IVIG) treatment and during convalescence in KD patients in comparison to healthy controls. Enzyme-linked immunosorbent assay (ELISA) corroborated the upregulation of TSLP in KD patients, which was exacerbated in convalescent patients complicated with thrombosis. TSLP receptors on platelets were also significantly upregulated in KD patients complicated with thrombosis. Platelet activation, apoptosis, and mitochondrial autophagy (mitophagy) were increased in convalescence KD patients complicated with thrombosis. In vitro, TSLP induced platelet activation and platelet mitophagy in healthy blood donors, as observed in KD patients. TSLP, similar to mitophagy agonist carbonyl cyanide 3-chlorophenyl hydrazone (CCCP), promoted thrombosis, which was attenuated by the mitophagy inhibitor Mdivi-1. Co-immunoprecipitation in TSLP-treated platelets revealed TSLP receptor (TSLPR) bound to mitophagy regulators, Parkin and Voltage Dependent Anion Channel Protein 1 (VDAC1).Thus, our results demonstrated that TSLP induced platelet mitophagy via a novel TSLPR/Parkin/VDAC1 pathway that promoted thrombosis in KD. These results suggest TSLP as a novel therapeutic target against KD-associated thrombosis.

Platelet Internalization Mediates Ferroptosis in Myocardial Infarction

BACKGROUND

Myocardial cell death is the hallmark of myocardial infarction. In the process of myocardial injury, platelets contribute to the pathogenesis by triggering intense inflammatory responses. Yet, it is still unclear if platelets regulate cardiomyocyte death directly, thereby exacerbating myocardial injury in myocardial infarction.

METHODS

We describe a mechanism underlying the correlative association between platelets accumulation and myocardial cell death by using myocardial infarction mouse model and patient specimens.

RESULTS

Myocardial infarction induces platelets internalization, resulting in the release of miR-223-3p, a platelet-enriched miRNA. By targeting the ACSL3, miR-223-3p delivered by internalized platelets cause the reduction of stearic acid-phosphatidylcholine in cardiomyocytes. The presence of stearic acid-phosphatidylcholine protects cardiomyocytes against ferroptosis.

CONCLUSIONS

Our work reveals a novel mechanism of platelet-mediated myocardial injury, highlighting antiplatelet therapies could potentially represent a multimechanism treatment of myocardial infarction, and implying ferroptosis being considered as novel target for therapeutics.

Vascular smooth muscle cells in intimal hyperplasia, an update

Arterial occlusive disease is the leading cause of death in Western countries. Core contemporary therapies for this disease include angioplasties, stents, endarterectomies and bypass surgery. However, these treatments suffer from high failure rates due to re-occlusive vascular wall adaptations and restenosis. Restenosis following vascular surgery is largely due to intimal hyperplasia. Intimal hyperplasia develops in response to vessel injury, leading to inflammation, vascular smooth muscle cells dedifferentiation, migration, proliferation and secretion of extra-cellular matrix into the vessel's innermost layer or intima. In this review, we describe the current state of knowledge on the origin and mechanisms underlying the dysregulated proliferation of vascular smooth muscle cells in intimal hyperplasia, and we present the new avenues of research targeting VSMC phenotype and proliferation.

MicroRNAs as Biomarkers for Coronary Artery Disease Related to Type 2 Diabetes Mellitus-From Pathogenesis to Potential Clinical Application

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease with still growing incidence among adults and young people worldwide. Patients with T2DM are more susceptible to developing coronary artery disease (CAD) than non-diabetic individuals. The currently used diagnostic methods do not ensure the detection of CAD at an early stage. Thus, extensive research on non-invasive, blood-based biomarkers is necessary to avoid life-threatening events. MicroRNAs (miRNAs) are small, endogenous, non-coding RNAs that are stable in human body fluids and easily detectable. A number of reports have highlighted that the aberrant expression of miRNAs may impair the diversity of signaling pathways underlying the pathophysiology of atherosclerosis, which is a key player linking T2DM with CAD. The preclinical evidence suggests the atheroprotective and atherogenic influence of miRNAs on every step of T2DM-induced atherogenesis, including endothelial dysfunction, endothelial to mesenchymal transition, macrophage activation, vascular smooth muscle cells proliferation/migration, platelet hyperactivity, and calcification. Among the 122 analyzed miRNAs, 14 top miRNAs appear to be the most consistently dysregulated in T2DM and CAD, whereas 10 miRNAs are altered in T2DM, CAD, and T2DM-CAD patients. This up-to-date overview aims to discuss the role of miRNAs in the development of diabetic CAD, emphasizing their potential clinical usefulness as novel, non-invasive biomarkers and therapeutic targets for T2DM individuals with a predisposition to undergo CAD.

Noncoding RNAs in Vascular Cell Biology and Restenosis

In-stent restenosis (ISR), characterised by ≥50% re-narrowing of the target vessel, is a common complication following stent implantation and remains a significant challenge to the long-term success of angioplasty procedures. Considering the global burden of cardiovascular diseases, improving angioplasty patient outcomes remains a key priority. Noncoding RNAs (ncRNAs) including microRNA (miRNA), long noncoding RNA (lncRNA) and circular RNA (circRNA) have been extensively implicated in vascular cell biology and ISR through multiple, both distinct and overlapping, mechanisms. Vascular smooth muscle cells, endothelial cells and macrophages constitute the main cell types involved in the multifactorial pathophysiology of ISR. The identification of critical regulators exemplified by ncRNAs in all these cell types and processes makes them an exciting therapeutic target in the field of restenosis. In this review, we will comprehensively explore the potential functions and underlying molecular mechanisms of ncRNAs in vascular cell biology in the context of restenosis, with an in-depth focus on vascular cell dysfunction during restenosis development and progression. We will also discuss the diagnostic biomarker and therapeutic target potential of ncRNAs in ISR. Finally, we will discuss the current shortcomings, challenges, and perspectives toward the clinical application of ncRNAs.

Pancreatic Cancer Cells Induce MicroRNA Deregulation in Platelets

Pancreatic cancer is a pathology with a high mortality rate since it is detected at advanced stages, so the search for early-stage diagnostic biomarkers is essential. Liquid biopsies are currently being explored for this purpose and educated platelets are a good candidate, since they are known to present a bidirectional interaction with tumor cells. In this work, we analyzed the effects of platelets on cancer cells’ viability, as determined by MTT, migration using transwell assays, clonogenicity in soft agar and stemness by dilution assays and stem markers’ expression. We found that the co-culture of platelets and pancreatic cancer cells increased the proliferation and migration capacity of BXCP3 cells, augmented clonogenicity and induced higher levels of Nanog, Sox2 and Oct4 expression. As platelets can provide horizontal transfer of microRNAs, we also determined the differential expression of miRNAs in platelets obtained from a small cohort of pancreatic cancer patients and healthy subjects. We found clear differences in the expression of several miRNAs between platelets of patients with cancer healthy subjects. Moreover, when we analyzed microRNAs from the platelets of the pancreatic juice and blood derived from each of the cancer patients, interestingly we find differences between the blood- and pancreatic juice-derived platelets suggesting the presence of different subpopulations of platelets in cancer patients, which warrant further analysis.

Platelet-derived microRNA-223 attenuates TNF-α induced monocytes adhesion to arterial endothelium by targeting ICAM-1 in Kawasaki disease

Background

Kawasaki disease (KD) is an acute vasculitis that may result in permanent coronary artery damage with unknown etiology. Endothelial cell (EC) dysfunction and platelet hyperactivity are the hallmarks of KD. Platelets are involved in the development of endothelial dysfunction. MiR-223 transferred by platelet microparticles (PMPs) has been found to involve in the functional regulation of endothelial cells in sepsis. However, the role of platelet-derived miR-223 in endothelial dysfunction has not yet been investigated in KD.

Objectives

We seek to investigate the role of platelet-derived miR-223 in endothelial dysfunction of KD vasculopathy.

Methods and results

Forty-five acute KD patients and 45 matched controls were randomly recruited in the study. When co-cultured with human coronary artery endothelial cells (HCAECs), KD platelets with higher levels of miR-223 were incorporated into HCAECs, resulting in the horizontal transfer of miR-223. Using KD platelets, PMPs, and platelet-releasate from the same amount of blood co-cultured with HCAECs, we found the increased expression of miR-223 in HCAECs was primarily derived from KD platelets, rather than PMPs or free miRNAs from platelet- releasate. KD platelet-derived miR-223 attenuated TNF-α induced intercellular cell adhesion molecule-1 (ICAM-1) expression in HCAECs. KD platelet-derived miR-223 also suppressed the monocyte adhesion to HCAECs. In vivo, platelet-specific miR-223 knockout (PF4-cre: miR-223^flox/flox) C57BL/6 mice and miR-223^flox/flox C57BL/6 mice were used. Using Lactobacillus casei cell wall extract (LCWE) to establish KD murine model, we showed that in LCWE-injected PF4-cre: miR-223^flox/flox mice, deficiency of platelet-miR-223 exacerbates the medial thickening of the abdominal aorta, increased ICAM-1 expression with concomitant CD45⁺ inflammatory cells infiltration into the endothelium compared to LCWE-injected miR-223^flox/flox mice.

Conclusions

The horizontal transfer of platelet-derived miR-223 suppresses the expression of ICAM-1 in HCAECs, which at least in part attenuates leukocyte adhesion, thereby reducing endothelial damage in KD vasculitis

Platelet TGF-β1 inhibits the migration and proliferation of smooth muscle cells in aneurysms

BACKGROUND

The study explored the role of platelet TGF-β1 from the perspective of inhibiting the excessive proliferation, migration and invasion of murine aortic vascular smooth muscle cells (MASMCs).

METHOD

The platelets were first extracted from C57BL/6 mice, and the TGF-β1 protein was obtained after the purification of protein. In vitro, the concentrations of angiotensin Ⅱ (Ang Ⅱ) and TGF-β1 for intervention were screened by testing the viability of MASMCs, followed by the analysis concerning the effects of platelets, Ang Ⅱ and TGF-β1 on the proliferation, migration, invasion, and the expressions of pathway-related proteins in MASMCs. In vivo, an Ang Ⅱ-induced mouse model was established. TGF-β1 was injected into the tail of mice as a therapeutic agent, and its action mechanism was further verified by the treatment of inhibitor SB505124. The results of the cell experiment were validated by evaluating the maximum diameter of abdominal aorta, the proportion of total weight, the changes of both pathology and the expressions of pathway-related proteins in the mice.

RESULT

0.5 ng/mL Ang Ⅱ and 15 ng/mL TGF-β1 were chosen for treatment. The following results of cell functional experiments and Western blot assay demonstrated that Ang Ⅱ promoted the proliferation, migration and invasion of MASMCs via regulating related pathways, the effects of which were evidently reversed by TGF-β1 and platelets. Consistent results were also observed in the animal experiments, where TGF-β1 effectively alleviated Ang Ⅱ-induced abdominal aortic injury in mice.

CONCLUSION

TGF-β1 in platelets inhibits Ang Ⅱ-induced proliferation, migration and invasion of MASMCs.

MicroRNAs as therapeutic targets in cardiovascular disease

The discovery of microRNAs and their role in diseases was a breakthrough that inspired research into microRNAs as drug targets. Cardiovascular diseases are an area in which limitations of conventional pharmacotherapy are highly apparent and where microRNA-based drugs have appreciably progressed into preclinical and clinical testing. In this Review, we summarize the current state of microRNAs as therapeutic targets in the cardiovascular system. We report recent advances in the identification and characterization of microRNAs, their manipulation and clinical translation, and discuss challenges and perspectives toward clinical application.

Mechanosensitive channel Piezo1 is required for pulmonary artery smooth muscle cell proliferation

Concentric pulmonary vascular wall thickening due partially to increased pulmonary artery (PA) smooth muscle cell (PASMC) proliferation contributes to elevating pulmonary vascular resistance (PVR) in patients with pulmonary hypertension (PH). Although pulmonary vasoconstriction may be an early contributor to increasing PVR, the transition of contractile PASMCs to proliferative PASMCs may play an important role in the development and progression of pulmonary vascular remodeling in PH. A rise in cytosolic Ca2+ concentration ([Ca2+]cyt) is a trigger for PASMC contraction and proliferation. Here, we report that upregulation of Piezo1, a mechanosensitive cation channel, is involved in the contractile-to-proliferative phenotypic transition of PASMCs and potential development of pulmonary vascular remodeling. By comparing freshly isolated PA (contractile PASMCs) and primary cultured PASMCs (from the same rat) in a growth medium (proliferative PASMCs), we found that Piezo1, Notch2/3, and CaSR protein levels were significantly higher in proliferative PASMCs than in contractile PASMCs. Upregulated Piezo1 was associated with an increase in expression of PCNA, a marker for cell proliferation, whereas downregulation (with siRNA) or inhibition (with GsMTx4) of Piezo1 attenuated PASMC proliferation. Furthermore, Piezo1 in the remodeled PA from rats with experimental PH was upregulated compared with PA from control rats. These data indicate that PASMC contractile-to-proliferative phenotypic transition is associated with the transition or adaptation of membrane channels and receptors. Upregulated Piezo1 may play a critical role in PASMC phenotypic transition and PASMC proliferation. Upregulation of Piezo1 in proliferative PASMCs may likely be required to provide sufficient Ca2+ to assure nuclear/cell division and PASMC proliferation, contributing to the development and progression of pulmonary vascular remodeling in PH.

LncRNA LINC00281/Annexin A2 Regulates Vascular Smooth Muscle Cell Phenotype Switching via the Nuclear Factor-Kappa B Signaling Pathway

Abnormal phenotype switch in vascular smooth muscle cells (VSMCs) plays an important role in the initiation and progression of vascular proliferative diseases. Annexin A2 (ANXA2), related to the pro-inflammatory response, contributes to the proliferation and migration of VSMCs. This study explored the mechanisms involved in the regulation of VSMC phenotype modulation via ANXA2. The results revealed that ANXA2 promotes the phosphorylation of p65 and co-translocates with p65 into the nucleus, resulting in VSMC proliferation, migration, and dedifferentiation. Based on bioinformatics predictions and RNA immunoprecipitation assays, LINC00281 was confirmed to be an upstream regulator of ANXA2. Taken together, ANXA2, which is negatively regulated by the long noncoding RNA (lncRNA) LINC00281, has significant importance in the regulation of VSMC proliferation, migration, and phenotype switching via the nuclear factor-kappa B (NF-кB) p65 signaling pathway. This indicates that the lncRNA LINC00281/ANXA2/NF-кB p65 signaling pathway might be a new therapeutic target for vascular proliferative diseases.

Intimal Hyperplasia of Arteriovenous Fistula

Intimal hyperplasia (IH), a crucial histopathological injury, forms the basis of vascular stenosis and thrombogenesis. In addition, it is common in maladies such as stenosis at the anastomosis of arteriovenous fistula and restenosis after angioplasty. Various cellular and noncellular components play critical parts in the advancement of IH. This article reviews the distinctive components of IH, such as endothelial dysfunction, multiplication, and movement of vascular smooth muscle cells. Finally, in addition to synthesis of large amounts of extracellular matrix and inflammatory responses, which have frequently been studied in recent years, we offer a premise for clinical treatment with vascular smooth muscle cells.

Vascular endothelial growth factor (VEGF) polymorphism rs3025039 and atherosclerosis among older with hypertension

Angiogenesis inhibition therapy causes hypertension by increasing peripheral vascular resistance. Vasa vasorum angiogenesis plays a crucial role in the development of atherosclerosis. Since vascular endothelial growth factor (VEGF), which contributes to the progress of angiogenesis, is reported to be inversely associated with the minor allele of polymorphism rs3025039, the minor allele of rs3025039 could be inversely associated with atherosclerosis among individuals with hypertension. A cross-sectional study of 1793 older Japanese adults aged 60–89 years with hypertension who participated in general health check-ups was conducted. Atherosclerosis was defined as carotid intima-media thickness (CIMT) ≥ 1.1 mm. The minor allele of polymorphism rs3025020 was positively associated with VEGF. Therefore, in addition to known cardiovascular risk factors, rs3025020 genotype acted as a confounding factor in the present study. Independent of known confounding factors, the minor allele of rs3025039 was inversely associated with atherosclerosis among older Japanese adults with hypertension. The fully adjusted odds ratio (OR) and 95% confidence interval (CI) for atherosclerosis with the minor allele of rs3025039 was 0.78 (0.64, 0.96). The angiogenesis-related polymorphism rs3025039 was associated with the development of atherosclerosis among older Japanese individuals. This study indicates that the development of atherosclerosis among older individuals might partly indicate a capacity for angiogenesis.

Plin5 inhibits proliferation and migration of vascular smooth muscle cell through interacting with PGC-1α following vascular injury

Abnormal proliferation and migration of vascular smooth muscle cell (VSMC) is a hallmark of vascular neointima hyperplasia. Perilipin 5 (Plin5), a regulator of lipid metabolism, is also confirmed to be involved in vascular disorders, such as microvascular endothelial dysfunction and atherosclerosis. To investigate the regulation and function of plin5 in the phenotypic alteration of VSMC, -an animal model of vascular intima hyperplasia was established in C57BL/6 J and Plin5 knockdown (Plin5±) mice by wire injure. Immunohistochemical staining was used to analyze neointima hyperplasia in artery. Ki-67, dihydroethidium immunofluorescence staining and wound healing assay were used to measure proliferation, reactive oxygen species (ROS) generation and migration of VSMC, respectively. Plin5 was downregulated in artery subjected to vascular injury and in VSMC subjected to platelet-derived growth factor (PDGF)-BB. Plin5 knockdown led to accelerated neointima hyperplasia, excessive proliferation and migration of VSMC after injury. In vitro, we observed increased ROS content in VSMC isolated from Plin5± mice. Antioxidative N-acetylcysteine (NAC) inhibited VSMC proliferation and migration induced by PDGF-BB or plin5 knockdown. More importantly, plin5-peroxlsome proliferator-activated receptor-γ coactivator (PGC)-1α interaction was also attenuated in VSMC after knockdown of plin5. Overexpression of PGC-1α suppressed PDGF-BB-induced ROS generation, proliferation, and migration in VSMC isolated from Plin5± mice. These data suggest that plin5 serves as a potent regulator of VSMC proliferation, migration, and neointima hyperplasia by interacting with PGC-1α and affecting ROS generation.

Non-coding RNAs in Kawasaki disease: Molecular mechanisms and clinical implications

Kawasaki disease (KD) is an acute self-limiting vasculitis with coronary complications, usually occurring in children. The incidence of KD in children is increasing year by year, mainly in East Asian countries, but relatively stably in Europe and America. Although studies on KD have been reported, the pathogenesis of KD is unknown. With the development of high-throughput sequencing technology, growing number of regulatory noncoding RNAs (ncRNAs) including microRNA (miRNA), long noncoding RNA (lncRNA), and circular RNA (circRNA) have been identified to involved in KD. However, the role of ncRNAs in KD has not been comprehensively elucidated. Therefore, it is significative to study the regulatory role of ncRNA in KD, which might help to uncover new and effective therapeutic strategies for KD. In this review, we summarize recent studies on ncRNA in KD from the perspectives of immune disorders, inflammatory disorders, and endothelial dysfunction, and highlight the potential of ncRNAs as therapeutic targets for KD.

A guide to molecular and functional investigations of platelets to bridge basic and clinical sciences

Platelets have been shown to be associated with pathophysiological process beyond thrombosis, demonstrating critical additional roles in homeostatic processes, such as immune regulation, and vascular remodeling. Platelets themselves can have multiple functional states and can communicate and regulate other cells including immune cells and vascular smooth muscle cells, to serve such diverse functions. Although traditional platelet functional assays are informative and reliable, they are limited in their ability to unravel platelet phenotypic heterogeneity and interactions. Developments in methods such as electron microscopy, flow cytometry, mass spectrometry, and 'omics' studies, have led to new insights. In this Review, we focus on advances in platelet biology and function, with an emphasis on current and promising methodologies. We also discuss technical and biological challenges in platelet investigations. Using coronavirus disease 2019 (COVID-19) as an example, we further describe the translational relevance of these approaches and the possible 'bench-to-bedside' utility in patient diagnosis and care.

Does hsa-miR-223-3p from platelet-derived extracellular vesicles regulate tissue factor expression in monocytic cells?

Extracellular vesicles (EVs) released from activated platelets contain microRNAs, the most abundant of which is hsa-miR-223-3p. Endogenous hsa-miR-223-3p suppresses the expression of tissue factor (TF), the initiator of the extrinsic coagulation pathway, in endothelial cells. Monocytes can be induced to express TF to enhance coagulation, but the role of hsa-miR-223-3p in regulating monocyte TF remains unknown. This study examined whether hsa-miR-223-3p from platelet-derived EVs (pdEVs) affects TF expression in monocytes. THP-1 cells, differentiated into a monocyte-like phenotype with 1α,25-dihydroxyvitaminD3, were transfected with hsa-miR-223-3p mimic or control microRNA. Alternatively, THP-1 cells were incubated with pdEVs from PAR1-agonist peptide activated-platelets, as platelet releasate, or pdEVs isolated by ultracentrifugation. Transfection with hsa-miR-223-3p mimic resulted in significant reductions in TF protein, determined by western blotting and flow cytometry and reduced procoagulant activity, measured by a TF-specific factor Xa generation assay, compared to cells transfected with control microRNA. This reduction was reversed by co-transfection with hsa-miR-223-3p inhibitor, AntagomiR-223. Incubation of THP-1 cells with pdEVs also decreased TF expression; however, this was not reversed by AntagomiR-223. Taken together, monocyte TF expression is downregulated by hsa-miR-223-3p, but when transferred via pdEVs the effect was not reversed with Antagomir-223, suggesting other pdEV components may contribute to TF regulation.Abbreviations: Tissue factor (TF), Factor VII (FVII), activated Factor VII (FVIIa), Factor X (FX), activated Factor X (FXa), extracellular vesicles (EVs), microvesicles (MVs), platelet-derived extracellular vesicles (pdEVs), protease-activated receptor 1 agonist peptide (PAR1-AP), lipopolysaccharide (LPS), P-selectin glycoprotein ligand-1 (PSGL-1), Tris-Buffered Saline Tween (TBST), room temperature (RT)[Figure: see text].

Platelets in the pathogenesis of flavivirus disease

Research on the role of platelets in modulating innate and adaptive host immune responses has gaining importance in the last two decades. Since the virus can directly interact with platelet receptors and modulate the host immune response, understanding the role of platelets in viral pathogenesis would pave way for novel therapeutic means. The present review aims at presenting the important molecular aspects of platelet-flavivirus interactions and how it leads to platelet activation, thrombocytopenia, and vascular endothelial leakage. Besides, the role of some of the platelet-derived factors as biomarkers for the early prediction of disease outcome taking dengue infection as an example is reviewed.

Transient Focal Cerebral Ischemia Leads to miRNA Alterations in Different Brain Regions, Blood Serum, Liver, and Spleen

Ischemic stroke is characterized by an occlusion of a cerebral blood vessel resulting in neuronal cell death due to nutritional and oxygen deficiency. Additionally, post-ischemic cell death is augmented after reperfusion. These events are paralleled by dysregulated miRNA expression profiles in the peri-infarct area. Understanding the underlying molecular mechanism in the peri-infarct region is crucial for developing promising therapeutics. Utilizing a tMCAo (transient Middle Cerebral Artery occlusion) model in rats, we studied the expression levels of the miRNAs (miR) 223-3p, 155-5p, 3473, and 448-5p in the cortex, amygdala, thalamus, and hippocampus of both the ipsi- and contralateral hemispheres. Additionally, the levels in the blood serum, spleen, and liver and the expression of their target genes, namely, Nlrp3, Socs1, Socs3, and Vegfa, were assessed. We observed an increase in all miRNAs on the ipsilateral side of the cerebral cortex in a time-dependent manner and increased miRNAs levels (miR-223-3p, miR-3473, and miR-448-5p) in the contralateral hemisphere after 72 h. Besides the cerebral cortex, the amygdala presented increased expression levels, whereas the thalamus and hippocampus showed no alterations. Different levels of the investigated miRNAs were detected in blood serum, liver, and spleen. The gene targets were altered not only in the peri-infarct area of the cortex but selectively increased in the investigated non-affected brain regions along with the spleen and liver during the reperfusion time up to 72 h. Our results suggest a supra-regional influence of miRNAs following ischemic stroke, which should be studied to further identify whether miRNAs are transported or locally upregulated.

An update on the phenotypic switching of vascular smooth muscle cells in the pathogenesis of atherosclerosis

Vascular smooth muscle cells (VSMCs) are involved in phenotypic switching in atherosclerosis. This switching is characterized by VSMC dedifferentiation, migration, and transdifferentiation into other cell types. VSMC phenotypic transitions have historically been considered bidirectional processes. Cells can adopt a physiological contraction phenotype or an alternative "synthetic" phenotype in response to injury. However, recent studies, including lineage tracing and single-cell sequencing studies, have shown that VSMCs downregulate contraction markers during atherosclerosis while adopting other phenotypes, including macrophage-like, foam cell, mesenchymal stem-like, myofibroblast-like, and osteochondral-like phenotypes. However, the molecular mechanism and processes regulating the switching of VSMCs at the onset of atherosclerosis are still unclear. This systematic review aims to review the critical outstanding challenges and issues that need further investigation and summarize the current knowledge in this field.

Association Between Platelet Levels on Admission and 90-day Mortality in Patients With Exertional Heatstroke, a 10 Years Cohort Study

Background: Heatstroke is a common clinical symptom in summer with high mortality requiring identification of appropriate and rapid methods of assessment.

Method: This is a retrospective study that included the recent 10 years clinical data of heatstroke patients. A total of n = 186 patients were included in this study and grouped based on platelet (PLT) abnormality observed on admission.

Results: In the study group, n = 120 patients (64.5%) patients had normal PLT and n = 66 patients (35.5%) had abnormal PLT. Compared with PLT-normal group, PLT-abnormal group had higher Acute Physiology and Chronic Health Evaluation II (APACHE II) scores [median 15.0 (IQR 11.5–21.5) vs. 9.0 (IQR 7.0–12.5)] and SOFA scores [median 6.0 (IQR 4.0–10.0) vs. 2.0 (IQR 2.0–4.0)], lower Sequential Organ Failure Assessment (GCS)[median 8.0 (IQR 5.0–12.0) vs. 13.0 (IQR 9.0–14.0)]. The PLT-abnormal group had severe organ damage, including damage to the coagulation system, liver, and kidney (all p < 0.05). Significant differences were noted in 90-day survival between the two groups even after correction for Age, GCS, White blood cell count (WBC), Neutrophil, International normalized ratio (INR), Activated partial thromboplastin time (APTT), Procalcitonin (PCT), Alanine aminotransferase (ALT), Creatine (CR), D-Dime (D-D) (Before correction P < 0.001; After correction P = 0.009).The area under the ROC curve for the prediction of mortality based on PLT was 80.7% (95% CI 0.726–0.888, P < 0.001), the optimal cutoff value was 94, the sensitivity was 77.3%, and the specificity was 82.6%.

Conclusion: Patients with heatstroke with platelet abnormalities during admission have more severe organ impairment and a lower 90-day survival rate even when adjusted for other factors.

LncRNA H19 abrogates the protective effects of curcumin on rat carotid balloon injury via activating Wnt/β-catenin signaling pathway

Intimal hyperplasia-induced restenosis is a common response to vascular endothelial damage caused by mechanical force or other stimulation, and is closely linked to vascular remodeling. Curcumin, a traditional Chinese medicine, exhibits potent protective effects in cardiovascular diseases; for example, it attenuates vascular remodeling. Although the suppressive effects of curcumin on diseases caused by vascular narrowing have been investigated, the underlying mechanisms remain unknown. Long non-coding RNAs (lncRNAs) regulate various pathological processes and affect the action of drugs. In the present study, we found that the curcumin remarkably downregulated the expression of lncRNA H19 and thereby inhibited intimal hyperplasia-induced vascular restenosis. Furthermore, the inhibition of the expression of H19 by curcumin resulted in the inactivation of the Wnt/β-catenin signaling. Overall, we show that curcumin suppresses intimal hyperplasia via the H19/Wnt/β-catenin pathway, implying that H19 is a critical molecule in the suppression of intimal hyperplasia after balloon injury by curcumin. These insights should be useful for potential application of curcumin as a therapeutic intervention in vascular stenosis.

Secreted modular calcium-binding protein 1 binds and activates thrombin to account for platelet hyperreactivity in diabetes

Secreted modular calcium-binding protein 1 (SMOC1) is an osteonectin/SPARC-related matricellular protein, whose expression is regulated by microRNA-223 (miR-223). Given that platelets are rich in miR-223, this study investigated the expression of SMOC1 and its contribution to platelet function. Human and murine platelets expressed SMOC1, whereas platelets from SMOC1+/- mice did not present detectable mature SMOC1 protein. Platelets from SMOC1+/- mice demonstrated attenuated responsiveness to thrombin (platelet neutrophil aggregate formation, aggregation, clot formation, Ca2+ increase, and β3 integrin phosphorylation), whereas responses to other platelet agonists were unaffected. SMOC1 has been implicated in transforming growth factor-β signaling, but no link to this pathway was detected in platelets. Rather, the SMOC1 Kazal domain directly bound thrombin to potentiate its activity in vitro, as well as its actions on isolated platelets. The latter effects were prevented by monoclonal antibodies against SMOC1. Platelets from miR-223-deficient mice expressed high levels of SMOC1 and exhibited hyperreactivity to thrombin that was also reversed by preincubation with monoclonal antibodies against SMOC1. Similarly, SMOC1 levels were markedly upregulated in platelets from individuals with type 2 diabetes, and the SMOC1 antibody abrogated platelet hyperresponsiveness to thrombin. Taken together, we have identified SMOC1 as a novel thrombin-activating protein that makes a significant contribution to the pathophysiological changes in platelet function associated with type 2 diabetes. Thus, strategies that target SMOC1 or its interaction with thrombin may be attractive therapeutic approaches to normalize platelet function in diabetes.

UTMD promoted local delivery of miR-34a-mimic for ovarian cancer therapy

MicroRNA-mediated gene therapy is emerging as a promising method for the treatment of ovarian cancer, but the development of miRNA mimic delivery vectors is still in its infancy, where the safety and efficacy of miR-34a-mimic remain unknown. Ultrasound-targeted microbubble destruction (UTMD) can be an effective and minimally invasive tool for the delivery of miR-34a-mimic in vitro and in vivo. Here, we describe a high-efficiency gene delivery strategy by using miR-34a-mimic loaded folate modified microbubbles (miR-34a-FM) with a portable ultrasonic irradiation system. Ultrasonic parameters, including acoustic intensity (AI), exposure time (ET) and duty cycle (DC), were optimized and the optimal acoustic condition (1.0 W/cm², 20 s, and 15% DC) was used to deliver miRNA-34a into cells in vitro. MiR-34a mimic was successfully introduced into the cytoplasm and was found to inhibit proliferation and induce apoptosis of SK-OV-3 cells. Next, miR-34a-mimic was delivered to tumor tissue via UTMD, inhibiting tumor growth and prolonging the survival time of mice. In summary, UTMD-mediated miR-34a-mimic delivery has potential application in the clinical treatment of ovarian cancer.