Endothelial to mesenchymal transition: at the axis of cardiovascular health and disease

An integrated and multifunctional homemade cell sensor platform based on Si-d-CQDs and CRISPR-Cas12a for CD31 detection during endothelial-to-mesenchymal transition

Endothelial-to-mesenchymal transition (EndMT) plays a crucial role in the initiation and progression of atherosclerosis and various disease processes. Cluster of differentiation 31 (CD31) is a significant marker in EndMT. Detecting CD31 is essential for early-stage monitoring of EndMT and diagnosing atherosclerosis. Herein, we propose a homemade electrochemical array sensor comprising four electrodes, applied for cell cultivation, electrical stimulation, and simultaneous electrochemical detection, offering a three-in-one approach for CD31 detection during EndMT. To enhance the analytical performance of the cell sensor, indium tin oxide/chitosan-MXene/polyaniline (ITO/CS-MXene/PANI) composites were synthesized. The synthesis process involved the polymerization of PANI on the surface of the CS-MXene-modified ITO electrode, resulting in the creation of highly biocompatible active sites for cell immobilization. Si-d-CQDs@acDNA-AptCD31-Fc, with exceptional photophysical and chemical properties, was integrated into the array sensor setup, which enabled the dual-mode detection of fluorescent and electrochemical signals in cultured cells. A CRISPR-Cas12a system was employed to cleave Si-d-CQDs@acDNA-AptCD31-Fc. Subsequently, the fragmented Fc molecules were enriched via electrochemistry to further amplify the electrochemical signals. Through the unique combination of programmable Si-d-CQDs@acDNA-AptCD31-Fc, the CRISPR-Cas12a system, and voltage enrichment, a novel "signal-on-off-super on" signal amplification strategy was developed. The cell sensor exhibited a wide linear range from 1 × 101 particles mL-1 to 1 × 106 particles mL-1 (R2 = 0.9912) and a detection limit of 4 particles mL-1. The proposed strategy presents a promising approach for developing CRISPR-Cas12a-based tools for detecting various stages of EndMT and opens a new window for dual-mode analysis applications.

Vascular Remodeling: The Multicellular Mechanisms of Pulmonary Hypertension

Pulmonary hypertension (PH) is a serious cardiovascular disease caused by a variety of pathogenic factors, which is characterized by increased pulmonary vascular resistance (PVR) and progressive elevation of mean pulmonary artery pressure (mPAP). This disease can lead to right ventricular hypertrophy and, in severe cases, right heart failure and even death. Vascular remodeling-a pathological modification involving aberrant vasoconstriction, cell proliferation, apoptosis resistance, and inflammation in the pulmonary vascular system-is a significant pathological hallmark of PH and a critical process in its progression. Recent studies have found that vascular remodeling involves the participation of a diversity of cellular pathological alterations, such as the dysfunction of pulmonary artery endothelial cells (PAECs), the proliferation and migration of pulmonary artery smooth muscle cells (PASMCs), the phenotypic differentiation of pulmonary artery fibroblasts, the inflammatory response of immune cells, and pericyte proliferation. This review focuses on the mechanisms and the intercellular crosstalk of these cells in the PH process, emphasizing recent advances in knowledge regarding cellular signaling pathways, inflammatory responses, apoptosis, and proliferation. To develop better treatments, a list of possible therapeutic approaches meant to slow down certain biological functions is provided, with the aim of providing new insights into the treatment of PH by simplifying the intricacies of these complex connections. In this review, comprehensive academic databases such as PubMed, Embase, Web of Science, and Google Scholar were systematically searched to discuss studies relevant to human and animal PH, with a focus on vascular remodeling in PH.

Molecular mechanisms of endothelial-mesenchymal transition and its pathophysiological feature in cerebrovascular disease

The phenomenon of endothelial-mesenchymal transition (EndMT), a distinct subtype of epithelial-mesenchymal transition (EMT), has garnered significant attention from scholars. EndMT refers to the process whereby endothelial cells (ECs) transform into mesenchymal cells in response to various stimuli, resulting in the loss of their original characteristics. This process has diverse implications in both physiological and pathological states. Under physiological conditions, EndMT plays a crucial role in the development of the cardiovascular system. Conversely, under pathological conditions, EndMT has been identified as a pivotal factor in the development of cardiovascular diseases. Nonetheless, a comprehensive overview of EndMT in cerebrovascular disease is currently lacking. Here, we discuss the heterogeneity of EndMT occurrence and the regulatory factors involved in its development and analyze the feasibility of EndMT as a therapeutic target, aiming to provide a solid theoretical foundation and evidence to address diseases caused by pathological EndMT.

Follicle-stimulating hormone promotes EndMT in endothelial cells by upregulating ALKBH5 expression

BACKGROUND

The incidence of atherosclerosis markedly rises following menopause. Our previous findings demonstrated that elevated follicle-stimulating hormone (FSH) levels in postmenopausal women accelerate atherosclerosis progression. Plaque instability, the fundamental pathological factor in acute coronary syndrome, primarily results from vascular embolism due to plaque rupture. Recent evidence highlights that endothelial-to-mesenchymal transition (EndMT) exacerbates plaque instability, although the link between FSH and EndMT has not been fully established. This investigation sought to explore the possible influence of FSH in modulating EndMT.

METHODS

In this study, apolipoprotein E-deficient (ApoE-/-) mice served as an atherosclerosis model, while human umbilical vascular endothelial cells (HUVECs) were used as cellular models. Protein levels were assessed through immunochemical techniques, gene expression was quantified via RT-qPCR, and nucleic acid-protein interactions were evaluated using immunoprecipitation. The m6A modification status was determined by MeRIP, and cellular behaviors were analyzed through standard biochemical assays.

RESULTS

Our results indicate that FSH induces EndMT both in vitro and in vivo. Additional investigation suggested that FSH upregulates the transcription factor Forkhead box protein M1 (FOXM1) at both protein and mRNA levels by enhancing the expression of AlkB homolog 5, RNA demethylase (ALKBH5). FSH reduces m6A modifications on FOXM1 through ALKBH5, leading to increased nascent transcript levels and mRNA stability of FOXM1. Dual-luciferase reporter assays highlighted cAMP-response element binding protein (CREB)'s essential function in facilitating the FSH-induced upregulation of ALKBH5.

CONCLUSIONS

These findings suggest that FSH promotes ALKBH5 expression, facilitates N6-methyladenosine (m6A) demethylation on FOXM1, and consequently, induces EndMT. This study elucidates the impact of FSH on plaque instability and provides insights into potential strategies to prevent acute coronary syndrome in postmenopausal women.

Isoforskolin, adenylate cyclase agonist, inhibits endothelial-to-mesenchymal transition in atherosclerosis

BACKGROUND

Atherosclerosis is a common chronic disease characterized by the formation of atheromatous plaques and endothelial dysfunction. Endothelial-to-mesenchymal transition (EndMT) has been identified as a crucial driver of atherosclerosis, with TGF-β serving as a pivotal mediator of EndMT. Isoforskolin (ISOF), derived from the plant Coleus forskohlii, is an effective activator of adenylyl cyclase (AC). AC can catalyze the production of cyclic adenosine monophosphate (cAMP), mediating various biological functions. Several phosphodiesterase (PDE) inhibitors that degrade cAMP have been clinically utilized in the treatment of atherosclerosis. However, the evidence regarding the efficacy and mechanisms of AC agonists in the treatment of atherosclerosis remains inadequate.

PURPOSE

In this study, our primary objective was to examine the therapeutic impact of ISOF on atherosclerosis and elucidate its potential mechanisms.

METHODS

Male ApoE-/- rats were fed a high-fat diet for 18 weeks and then administered ISOF by gavage continuously for 12 weeks. A cell model was established by injuring mouse aortic endothelial cells (MAECs) with ox-LDL. Oil Red O staining and Masson staining were used to assess the plaque area and content of collagen. Aortic vasodilatory function was analyzed using the DMT Myograph system. Immunofluorescence was used to determine the localization of CD31 and α-SMA. Proteomics analysis was utilized to identify potential pharmacological mechanisms of ISOF. Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to detect the mRNA expression levels of AC (1-10) in aortic tissue. AC activity and cAMP concentration were detected using specific kits. The CCK-8 assay, wound-healing, and transwell assays were used to measure cell viability and proliferation. Mechanistically, western blot analysis was used to detect candidate protein expression levels. Finally, the pharmacological knockdown of AC5 was employed to clarify the potential mechanism of ISOF.

RESULTS

ISOF effectively inhibited atherosclerotic plaque progression and improved aortic vasodilatory function in ApoE-/- rats fed a high-fat diet. At the cellular level, ISOF enhanced cell viability and proliferation of MAECs compromised by ox-LDL. These phenotypic improvements were attributed to the inhibitory effect of ISOF on endothelial-to-mesenchymal transition (EndMT); ISOF increased the expression of endothelial markers such as CD31 and E-cadherin while decreasing the expression of mesenchymal markers, including N-cadherin and α-SMA. Mechanistically, and consistent with the results of proteomic analysis, ISOF markedly inhibited the TGF-β/Smad3 signaling pathway both in vivo and in vitro. Furthermore, the expression levels of adenylyl cyclase 5 (AC5) were significantly higher than those of other AC isoforms in rat aorta. ISOF might upregulate the expression of AC5, subsequently activating downstream protein kinase A (PKA) but not cAMP-activated exchange protein-1 (EPAC1). However, when AC5 was silenced, the effects of ISOF on EndMT and the cAMP/PKA/TGF-β pathway were effectively abolished.

CONCLUSION

The study showed that ISOF effectively combats atherosclerosis by inhibiting EndMT through the regulation of the AC5-dependent cAMP/PKA/TGF-β axis. This finding suggests a potential promising therapeutic strategy for treating atherosclerosis.

Cardiac Fibrosis in the Multi-Omics Era: Implications for Heart Failure

Cardiac fibrosis, a hallmark of heart failure and various cardiomyopathies, represents a complex pathological process that has long challenged therapeutic intervention. High-throughput omics technologies have begun revolutionizing our understanding of the molecular mechanisms driving cardiac fibrosis and are providing unprecedented insights into its heterogeneity and progression. This review provides a comprehensive analysis of how techniques-encompassing genomics, epigenomics, transcriptomics, proteomics, and metabolomics-are providing insight into our understanding of cardiac fibrosis. Genomic studies have identified novel genetic variants and regulatory networks associated with fibrosis susceptibility and progression, and single-cell transcriptomics has unveiled distinct cardiac fibroblast subpopulations with unique molecular signatures. Epigenomic profiling has revealed dynamic chromatin modifications controlling fibroblast activation states, and proteomic analyses have identified novel biomarkers and potential therapeutic targets. Metabolomic studies have uncovered important alterations in cardiac energetics and substrate utilization during fibrotic remodeling. The integration of these multi-omic data sets has led to the identification of previously unrecognized pathogenic mechanisms and potential therapeutic targets, including cell-type-specific interventions and metabolic modulators. We discuss how these advances are driving the development of precision medicine approaches for cardiac fibrosis while highlighting current challenges and future directions in translating multi-omic insights into effective therapeutic strategies. This review provides a systems-level perspective on cardiac fibrosis that may inform the development of more effective, personalized therapeutic approaches for heart failure and related cardiovascular diseases.

PD-1 inhibition disrupts collagen homeostasis and aggravates cardiac dysfunction through endothelial-fibroblast crosstalk and EndMT

Introduction

Cardiac immune-related adverse events (irAEs) from PD-1-targeting immune check-point inhibitors (ICIs) are an increasing concern due to their high mortality rate. Collagen plays a crucial role in maintaining cardiac structure, elasticity, and signal transduction; however, the effects and mechanisms of PD-1 inhibitor on cardiac collagen remodeling remain poorly understood.

Methods

C57BL/6 mice were injected with anti-mouse PD-1 antibody to create a PD-1 inhibitor-treated model. Cardiac function was measured by echocardiography, and collagen distribution was analyzed with Masson's trichrome staining and Sirius Red staining. Single-nucleus RNA sequencing was performed to examine the effects of PD-1 inhibition on gene expression in cardiac fibroblasts (CFs) and endothelial cells (ECs). EC-CF crosstalk was assessed using co-culture experiments and ELISA. ChIP assay was performed to analyze the regulation of TCF12 on TGF-β1 promoter. Western blot, qRT-PCR, and immunofluorescence staining were used to detect the expression of TCF12, TGF-β1, and endothelial-to-mesenchymal transition (EndMT) markers. Reactive oxygen species (ROS) levels were evaluated by DHE staining, MDA content, and SOD activity assays.

Results

We report a newly discovered cardiotoxic effect of PD-1 inhibitor, which causes aberrant collagen distribution in the heart, marked by a decrease in interstitial collagen and an increase in perivascular collagen deposition. Mechanistically, PD-1 inhibitor does not directly affect CFs but instead impact them through EC-CF crosstalk. PD-1 inhibitor reduces TGF-β1 secretion in ECs by downregulating TCF12, which we identify as a transcriptional promoter of TGF-β1. This subsequently decreases CF activity, leading to reduced interstitial collagen deposition. Additionally, PD-1 inhibitor induces EndMT, increasing perivascular collagen deposition. The endothelial dysfunction induced by PD-1 inhibitor results from ROS accumulation in ECs. Inhibiting ROS with N-acetylcysteine (NAC) preserves normal collagen distribution and cardiac function in PD-1 inhibitor-treated mice by reversing TCF12 downregulation and EndMT in ECs.

Conclusion

Our results suggest that PD-1 inhibitor causes ROS accumulation in cardiac ECs, leading to imbalanced collagen distribution (decrease in interstitial collagen and increase in perivascular collagen) in the heart by modulating TCF12/TGF-β1-mediated EC-CF crosstalk and EndMT. NAC supplementation could be an effective clinical strategy to mitigate PD-1 inhibitor-induced imbalanced collagen distribution and cardiac dysfunction.

Opportunities and challenges for the use of human samples in translational cardiovascular research: a scientific statement of the ESC Working Group on Cellular Biology of the Heart, the ESC Working Group on Cardiovascular Surgery, the ESC Council on Basic Cardiovascular Science, the ESC Scientists of Tomorrow, the European Association of Percutaneous Cardiovascular Interventions of the ESC, and the Heart Failure Association of the ESC

Animal models offer invaluable insights into disease mechanisms but cannot entirely mimic the variability and heterogeneity of human populations, nor the increasing prevalence of multi-morbidity. Consequently, employing human samples-such as whole blood or fractions, valvular and vascular tissues, myocardium, pericardium, or human-derived cells-is essential for enhancing the translational relevance of cardiovascular research. For instance, myocardial tissue slices, which preserve crucial structural and functional characteristics of the human heart, can be used in vitro to examine drug responses. Human blood serves as a rich source of biomarkers, including extracellular vesicles, various types of RNA (miRNA, lncRNA, and circRNAs), circulating inflammatory cells, and endothelial colony-forming cells, facilitating detailed studies of cardiovascular diseases. Primary cardiomyocytes and vascular cells isolated from human tissues are invaluable for mechanistic investigations in vitro. In cases where these are unavailable, human induced pluripotent stem cells serve as effective substitutes, albeit with specific limitations. However, the use of human samples presents challenges such as ethical approvals, tissue procurement and storage, variability in patient genetics and treatment regimens, and the selection of appropriate control samples. Biobanks are central to the efficient use of these scarce and valuable resources. This scientific statement discusses opportunities to implement the use of human samples for cardiovascular research within specific clinical contexts, offers a practical framework for acquiring and utilizing different human materials, and presents examples of human sample applications for specific cardiovascular diseases, providing a valuable resource for clinicians, translational and basic scientists engaged in cardiovascular research.

Diabetes-Driven Atherosclerosis: Updated Mechanistic Insights and Novel Therapeutic Strategies

The global rise in diabetes prevalence has significantly contributed to the increasing burden of atherosclerotic cardiovascular disease (ASCVD), a leading cause of morbidity and mortality in this population. Diabetes accelerates atherosclerosis through mechanisms such as hyperglycemia, oxidative stress, chronic inflammation, and epigenetic dysregulation, leading to unstable plaques and an elevated risk of cardiovascular events. Despite advancements in controlling traditional risk factors like dyslipidemia and hypertension, a considerable residual cardiovascular risk persists, highlighting the need for innovative therapeutic approaches. Emerging treatments, including sodium-glucose cotransporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, epigenetic modulators, and RNA-based therapies, are showing promise in addressing the unique challenges of diabetes-associated ASCVD. Precision medicine strategies, such as nanoparticle-based drug delivery and cell-specific therapies, offer further potential for mitigating cardiovascular complications. Advances in multiomics and systems biology continue to deepen our understanding of the molecular mechanisms driving diabetes-associated atherosclerosis. This review synthesizes recent advances in understanding the pathophysiology and treatment of diabetes-related atherosclerosis, offering a roadmap for future research and precision medicine approaches to mitigate cardiovascular risk in this growing population.

Characterization of the Temporal Dynamics of the Endothelial-Mesenchymal-like Transition Induced by Soluble Factors from Dengue Virus Infection in Microvascular Endothelial Cells

Dengue virus (DV) infection poses a severe life-threatening risk in certain cases. This is mainly due to endothelial dysregulation, which causes plasma leakage and hemorrhage. However, the etiology of DV-induced endothelial dysregulation remains incompletely understood. To identify the potential mechanisms of endothelial dysregulation caused by DV, the effects of conditioned media from Dengue virus (CMDV) on the mechanics and transcriptional profile of the endothelial cells were examined using permeability assays, atomic force microscopy, In-Cell Western blot and in silico transcriptomics. Exposure of HMEC-1 cells to the CMDV increased endothelial permeability and cellular stiffness. It also induced the expression of the key proteins associated with endothelial-to-mesenchymal transition (EndMT). These data support the notion that the DV promotes endothelial dysfunction by triggering transcriptional programs that compromise the endothelial barrier function. Understanding the molecular mechanisms underlying DV-induced endothelial dysregulation is crucial for developing targeted therapeutic strategies to mitigate the severe outcomes associated with dengue infection.

Endothelial-mesenchymal crosstalk drives osteogenic differentiation of human osteoblasts through Notch signaling

BACKGROUND

Angiogenesis and osteogenesis are closely interrelated. The interaction between endothelial and bone-forming cells, such as osteoblasts, is crucial for normal bone development and repair. Juxtacrine and paracrine mechanisms play key roles in cell differentiation towards the osteogenic direction, assuming the direct effect of endothelium on osteogenic differentiation. However, the mechanisms of this interplay have yet to be thoroughly studied.

METHODS

Isolated endothelial cells (EC) from human umbilical vein and human osteoblasts (OB) from the epiphysis of the femur or tibia were cultured in direct and indirect (separated by membrane) contact in vitro under the osteogenic differentiation conditions. Osteogenic differentiation was verified by RT-PCR, and alizarin red staining. Shotgun proteomics and RNA-sequencing were used to compare both EC and OB under different co-culture conditions to assess the mechanisms of EC-OB interplay. To verify the role of Notch signaling, experiments with Notch modulation in EC were performed by EC lentiviral transduction with further co-cultivation with OB. Additionally, the effect of Notch modulation in EC was assessed by RNA-sequencing.

RESULTS

EC have opposite effects on osteogenic differentiation depending on the co-culture conditions with OB. In direct contact, EC enhance osteogenic differentiation, but in indirect cultures, EC suppress it. Our proteotranscriptomic analysis revealed that the osteosuppressive effect is related to the action of paracrine factors secreted by EC, while the osteoinductive properties of EC are mediated by the Notch signaling pathway, which can be activated only upon a physical contact of EC with OB. Indeed, in the direct co-culture, the knockdown of Notch1 and Notch3 receptors in EC has an inhibitory effect on the OB osteogenic differentiation, whereas activation of Notch by intracellular domain of either Notch1 or Notch3 in EC has an inductive effect on the OB osteogenic differentiation.

CONCLUSION

The data indicate the dual role of the endothelium in regulating osteogenic differentiation and highlight the unique role of the Notch signaling pathway in inducing osteogenic differentiation during cell-to-cell interactions. The findings of the study emphasize the importance of intercellular communication in the regulation of osteoblast differentiation during bone development and maintenance.

Uncovering endothelial to mesenchymal transition drivers in atherosclerosis via multi-omics analysis

PURPOSE

This study aimed to identify novel candidates that regulate Endothelial to mesenchymal transition(EndMT) in atherosclerosis by integrating multi-omics data.

METHODS

The single-cell RNA sequencing (scRNA-seq) dataset GSE159677, bulk RNA-seq dataset GSE118446 and microarray dataset GSE56309 were obtained from the Gene Expression Omnibus (GEO) database. The uniform manifold approximation and projection (UMAP) were used for downscaling and cluster identification. Differentially expressed genes (DEGs) from GSE118446 and GSE56309 were analyzed using limma package. Functional enrichment analysis was applied by DAVID functional annotation tool. Quantitative real-time polymerase chain reaction (qPCR) and western blotting were used for further validation.

RESULTS

Nine endothelial cell (EC) clusters were identified in human plaques, with EC cluster 5 exhibiting an EndMT phenotype. The intersection of genes from EC cluster 5 and common DEGs in vitro EndMT models revealed seven mesenchymal candidates: PTGS2, TPM1, SERPINE1, FN1, RASD1, SEMA3C, and ESM1. Validation of these findings was carried out through qPCR analysis.

CONCLUSION

Through the integration of multi-omics data using bioinformatics methods, our study identified seven novel EndMT candidates: PTGS2, TPM1, SERPINE1, FN1, RASD1, SEMA3C, and ESM1.

Cardiotoxicity Beyond Cardiomyocytes-Focus on the Role of Cardiac Fibroblasts and Endothelial Cells

INTRODUCTION

Anti-cancer treatments frequently have serious adverse effects on the cardiovascular system. Understanding the mechanisms underlying these cancer therapy-related cardiovascular toxicities is essential for their prevention and potential treatment. While research often centres on cardiomyocyte damage as the primary cause of cardiac injury, the roles of cardiac fibroblasts and endothelial cells are often neglected. In this study, we aimed to investigate the direct toxicity in cardiac fibroblast and endothelial cells of 35 FDA-approved anti-cancer drugs, of which the effects previously only had been explored in cardiomyocytes.

METHODS AND RESULTS

Metabolic cell viability in cardiac fibroblasts and endothelial cells was first determined using the CellTiter-Glo luminescence assay. If metabolic cell viability was reduced, lactate dehydrogenase was measured in the supernatant to assess cytotoxicity. Interestingly, certain anti-cancer treatments were able to increase metabolic cell viability. For these drugs, gene expression analysis assessing for myofibroblast differentiation and endothelial-to-mesenchymal transition was performed.

CONCLUSION

Our study demonstrates that anti-cancer therapies indeed exhibited different toxicity profiles in cardiac fibroblasts and endothelial cells compared to cardiomyocytes and triggers specific pathophysiological transformations in response to anti-cancer drug exposure.

Involvement of USP7 in aggravating Kawasaki disease by promoting TGFβ2 signaling mediated endothelial-mesenchymal transition and coronary artery remodeling

Kawasaki disease (KD), characterized by systematic vasculitis, is a leading cause of pediatric heart disease. Although recent studies have highlighted the critical role of deubiquitinases in vascular pathophysiology, their specific contribution to KD remains largely unknown. Herein, we investigated the function of the deubiquitinase USP7 in both KD patients and a CAWS-induced KD murine model. USP7 expression level is increased both in HCAECs induced by KD sera and cardiac CD31+ endothelial cells of KD mice. Whereas knockout of USP7 increases the cellular proportion of endothelial cells and potentially attenuates the elevated EndoMT, fibrosis, and inflammation in cardiac tissue of KD mice, consistently with the in vitro experiment observed in HCAECs induced by TGF-β2. Mechanistically, USP7 interacts with SMAD2/3, enhancing their protein stability by removing the K48 ubiquitin chain from both proteins and preventing their proteasome degradation, thus increasing the p-SMAD2 levels and nuclear entry. Importantly, intraperitoneal injection of USP7 inhibitor, P22077 elicited a robust anti-EndoMT and anti-vascular inflammation effect in KD model mice. Therefore, our study uncovered a previously unrecognized function of increased USP7 in KD by augmenting TGFβ2/SMAD2/SMAD3 signaling, thus facilitating the transcription of genes implicated in the EndoMT, cardiac fibrosis, and vascular remodeling. Our finding suggests that USP7 could serve as a potential therapeutic target for the prevention and treatment of coronary artery lesions in KD and related vascular diseases.

Targeting fibroblast phenotype switching in cardiac remodelling as a promising antifibrotic strategy

Myocardial fibrosis, a common feature of heart disease, remains an unsolved clinical challenge. Fibrosis resolution requires activation of cardiac fibroblasts exhibiting context-dependent beneficial and detrimental dichotomy. Here, we explored the hypothesis of fibroblast reversible transition between quiescence and activated myofibroblastic states as a manifestation of cell phenotypic switching in myocardial remodelling. In support, gene regulatory networks executing conversion of cardiac fibroblasts to myofibroblasts and vice versa in fibrosis resolution are reconstructed using TRANSPATH database. In a scenario of fibroblast activation triggered by transforming growth factor β, a cardinal mediator of tissue fibrosis, signalling cascades governing entry into or exit from specific fibroblast statures in cardiac fibrotic remodelling were dissected. It is suggested that fibroblast phenotypic switching constitutes the central gait toward guiding cell state-gating strategies to counteract adverse cardiac fibrosis, a devastating disorder with no approved therapeutic option.

Atherosclerosis in diabetes mellitus: novel mechanisms and mechanism-based therapeutic approaches

Atherosclerosis is a disease of large and medium arteries that can lead to life-threatening cardiovascular and cerebrovascular consequences, such as myocardial infarction and stroke. Moreover, atherosclerosis is a major contributor to cardiovascular-related mortality in individuals with diabetes mellitus. Diabetes aggravates the pathobiological mechanisms that underlie the development of atherosclerosis. Currently available anti-atherosclerotic drugs or strategies solely focus on optimal control of systemic risk factors, including hyperglycaemia and dyslipidaemia, but do not adequately target the diabetes-exacerbated mechanisms of atherosclerotic cardiovascular disease, highlighting the need for targeted, mechanism-based therapies. This Review focuses on emerging pathological mechanisms and related novel therapeutic targets in atherosclerotic cardiovascular disease in patients with diabetes.

Reconceptualizing Endothelial-to-mesenchymal transition in atherosclerosis: Signaling pathways and prospective targeting strategies

BACKGROUND

The modification of endothelial cells (ECs) biological function under pathogenic conditions leads to the expression of mesenchymal stromal cells (MSCs) markers, defined as endothelial-to-mesenchymal transition (EndMT). Invisible in onset and slow in progression, atherosclerosis (AS) is a potential contributor to various atherosclerotic cardiovascular diseases (ASCVD). By triggering AS, EndMT, the "initiator" of AS, induces the progression of ASCVD such as coronary atherosclerotic heart disease (CHD) and ischemic cerebrovascular disease (ICD), with serious clinical complications such as myocardial infarction (MI) and stroke. In-depth research of the pathomechanisms of EndMT and identification of potential targeted therapeutic strategies hold considerable research value for the prevention and treatment of ASCVD-associated with delayed EndMT. Although previous studies have progressively unraveled the complexity of EndMT and its pathogenicity triggered by alterations in vascular microenvironmental factors, systematic descriptions of the most recent pathogenic roles of EndMT in the progression of AS, targeted therapeutic strategies, and their future research directions are scarce.

AIM OF REVIEW

We aim to provide new researchers with comprehensive knowledge of EndMT in AS. We exhaustively review the latest research advancements in the field and provide a theoretical basis for investigating EndMT, a biological process with sophisticated mechanisms.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review summarized that altered hemodynamics with microenvironmental crosstalk consisting of inflammatory responses or glycolysis, oxidative stress, lactate or acetyl-CoA (Ac-CoA), fatty acid oxidation (FAO), intracellular iron overload, and transcription factors, including ELK1 and STAT3, modulate the EndMT and affect AS progression. In addition, we provide new paradigms for the development of promising therapeutic agents against these disease-causing processes and indicate promising directions and challenges that need to be addressed to elucidate the EndMT process.

Intracellular endothelial cell metabolism in vascular function and dysfunction

Endothelial cells (ECs) form the inner lining of blood vessels that is crucial for vascular function and homeostasis. They regulate vascular tone, oxidative stress, and permeability. Dysfunction leads to increased permeability, leukocyte adhesion, and thrombosis. ECs undergo metabolic changes in conditions such as wound healing, cancer, atherosclerosis, and diabetes, and can influence disease progression. We discuss recent research that has revealed diverse intracellular metabolic pathways in ECs that are tailored to their functional needs, including lipid handling, glycolysis, and fatty acid oxidation (FAO). Understanding EC metabolic signatures in health and disease will be crucial not only for basic biology but can also be exploited when designing new therapies to target EC-related functions in different vascular diseases.

PCSK9 inhibitor alleviates experimental pulmonary fibrosis-induced pulmonary hypertension via attenuating epithelial-mesenchymal transition by suppressing Wnt/β-catenin signaling in vivo and in vitro

Background

The co-occurrence of pulmonary hypertension (PH) in patients with pulmonary fibrosis (PF) is linked to a more unfavorable prognosis and increased mortality compared to PF cases without PH. Early intervention and comprehensive management are pivotal for improving survival outcomes. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protein essential in cholesterol metabolism. However, the potential for PCSK9 inhibition to alleviate PF-induced PH has not been previously reported.

Methods

A mouse model of PF-induced PH was established using intratracheal injection of bleomycin (BLM), followed by administration of a PCSK9 inhibitor every other day. Data on right ventricle (RV) remodeling and changes in pulmonary arteries were collected and analyzed. Transforming growth factor-beta (TGF-β) was also administered to MLE-12 cells as an experimental lung fibrosis model. The mechanisms of PCSK9's impact on lung fibrosis were examined both in vivo and in vitro.

Results

Inhibition of PCSK9 significantly reduced pulmonary artery thickening and RV remodeling in the BLM-induced mouse model. Moreover, the blockage of PCSK9 effectively attenuated the migration and epithelial-mesenchymal transition (EMT) process of TGF-β-induced MLE-12 cells. We also observed that the PCSK9 inhibitor suppressed the expression of the Wnt/β-catenin pathway in both animal and cell experiments.

Conclusion

PCSK9 plays a crucial role in the progression of PF-induced PH by regulating cell EMT and Wnt/β-catenin signaling. Targeting PCSK9 expression or activity could effectively control lung fibrosis and its PH complication.

Heat shock protein 27 downregulation attenuates isoprenaline-induced myocardial fibrosis and diastolic dysfunction by modulating the endothelial-mesenchymal transition

Heart failure (HF), an end-stage clinical syndrome secondary to cardiac impairment, significantly affects patients' quality of life and long-term prognosis. Myocardial fibrosis leads to systolic and diastolic dysfunction, and promotes the progression of HF. Several studies involving the modulation of myocardial fibrosis have been conducted in an effort to improve cardiac function. Heat shock protein 27 (HSP27) is a small chaperone protein that is overexpressed in cellular stress states. HSP27 modulates epithelial-mesenchymal transition, playing a crucial role in the pathology of several fibrotic diseases. However, its association with myocardial fibrosis regulation is unknown. This study aimed to investigate the mechanisms by which HSP27 regulates myocardial fibrosis. We created cardiac-specific HSP25 (the murine ortholog of human HSP27) knockout mice and found that HSP25 knockdown inhibited endothelial-mesenchymal transition (EndMT), attenuated myocardial fibrosis, and ameliorated diastolic dysfunction in isoproterenol-induced HF mice via echocardiography, histology, and western bloting. In vitro, HSP27 knockdown attenuated transforming growth factor beta-induced EndMT, whereas HSP27 overexpression promoted EndMT. Furthermore, the SMAD3/SNAIL1 pathway was found to be crucial for HSP27-mediated EndMT regulation. As an essential molecule in EndMT regulation and myocardial fibrosis modulation, HSP27 may hold promise as a therapeutic target for patients with HF.

Pathophysiology in Brain Arteriovenous Malformations: Focus on Endothelial Dysfunctions and Endothelial-to-Mesenchymal Transition

Brain arteriovenous malformations (bAVMs) substantially increase the risk for intracerebral hemorrhage (ICH), which is associated with significant morbidity and mortality. However, the treatment options for bAVMs are severely limited, primarily relying on invasive methods that carry their own risks for intraoperative hemorrhage or even death. Currently, there are no pharmaceutical agents shown to treat this condition, primarily due to a poor understanding of bAVM pathophysiology. For the last decade, bAVM research has made significant advances, including the identification of novel genetic mutations and relevant signaling in bAVM development. However, bAVM pathophysiology is still largely unclear. Further investigation is required to understand the detailed cellular and molecular mechanisms involved, which will enable the development of safer and more effective treatment options. Endothelial cells (ECs), the cells that line the vascular lumen, are integral to the pathogenesis of bAVMs. Understanding the fundamental role of ECs in pathological conditions is crucial to unraveling bAVM pathophysiology. This review focuses on the current knowledge of bAVM-relevant signaling pathways and dysfunctions in ECs, particularly the endothelial-to-mesenchymal transition (EndMT).

The Role of Endothelial Cell Mitophagy in Age-Related Cardiovascular Diseases

Aging is a major risk factor for cardiovascular diseases (CVD), and mitochondrial autophagy impairment is considered a significant physiological change associated with aging. Endothelial cells play a crucial role in maintaining vascular homeostasis and function, participating in various physiological processes such as regulating vascular tone, coagulation, angiogenesis, and inflammatory responses. As aging progresses, mitochondrial autophagy impairment in endothelial cells worsens, leading to the development of numerous cardiovascular diseases. Therefore, regulating mitochondrial autophagy in endothelial cells is vital for preventing and treating age-related cardiovascular diseases. However, there is currently a lack of systematic reviews in this area. To address this gap, we have written this review to provide new research and therapeutic strategies for managing aging and age-related cardiovascular diseases.

Extracellular Vesicles Derived from Type 2 Diabetic Mesenchymal Stem Cells Induce Endothelial Mesenchymal Transition under High Glucose Conditions Through the TGFβ/Smad3 Signaling Pathway

Type 2 diabetes mellitus (T2DM) is associated with endothelial dysfunction, which results in delayed wound healing. Mesenchymal stem cells (MSCs) play a vital role in supporting endothelial cells (ECs) and promoting wound healing by paracrine effects through their secretome-containing extracellular vesicles. We previously reported the impaired wound healing ability of adipose tissue-derived MSC from T2DM donors; however, whether extracellular vesicles isolated from T2DM adipose tissue-derived MSCs (dEVs) exhibit altered functions in comparison to those derived from healthy donors (nEVs) is still unclear. In this study, we found that nEVs induced EC survival and angiogenesis, whereas dEVs lost these abilities. In addition, under high glucose conditions, nEV protected ECs from endothelial-mesenchymal transition (EndMT), whereas dEV significantly induced EndMT by activating the transforming growth factor-β/Smad3 signaling pathway, which impaired the tube formation and in vivo wound healing abilities of ECs. Interestingly, the treatment of dEV-internalized ECs with nEVs rescued the induced EndMT effects. Of note, the internalization of nEV into T2DM adipose tissue-derived MSC resulted in the production of an altered n-dEV, which inhibited EndMT and supported the survival of T2DM db/db mice from severe wounds. Taken together, our findings suggest the role of dEV in endothelial dysfunction and delayed wound healing in T2DM by the promotion of EndMT. Moreover, nEV treatment can be considered a promising candidate for cell-free therapy to protect ECs in T2DM.

Tectorigenin protects against cardiac fibrosis in diabetic mice heart via activating the adiponectin receptor 1-mediated AMPK pathway

Diabetic cardiomyopathy (DCM) is a common severe complication of diabetes that occurs independently of hypertension, coronary artery disease, and valvular cardiomyopathy, eventually leading to heart failure. Previous studies have reported that Tectorigenin (TEC) possesses extensive anti-inflammatory and anti-oxidative stress properties. In this present study, the impact of TEC on diabetic cardiomyopathy was examined. The model of DCM in mice was established with the combination of a high-fat diet and STZ treatment. Remarkably, TEC treatment significantly attenuated cardiac fibrosis and improved cardiac dysfunction. Concurrently, TEC was also found to mitigate hyperglycemia and hyperlipidemia in the DCM mouse. At the molecular level, TEC is involved in the activation of AMPK, both in vitro and in vivo, by enhancing its phosphorylation. This is achieved through the regulation of endothelial-mesenchymal transition via the AMPK/TGFβ/Smad3 pathway. Furthermore, it was demonstrated that the level of ubiquitination of the adiponectin receptor 1 (AdipoR1) protein is associated with TEC-mediated improvement of cardiac dysfunction in DCM mice. Notably the substantial reduction of myocardial fibrosis. In conclusion, TEC improves cardiac fibrosis in DCM mice by modulating the AdipoR1/AMPK signaling pathway. These findings suggest that TEC could be an effective therapeutic agent for the treatment of diabetic cardiomyopathy.