Targeting VEGF-A/VEGFR2 Y949 Signaling-Mediated Vascular Permeability Alleviates Hypoxic Pulmonary Hypertension

Distinct Effects of Sevoflurane and Propofol on Vascular Permeability In Vitro and in a Mouse Model

BACKGROUND

General anesthetics may substantially influence endothelium function, potentially affecting outcomes of surgical patients, but their effects are unclear. Here, the authors studied a commonly used inhaled anesthetic, sevoflurane, and an intravenous anesthetic, propofol, on vascular endothelial permeability using multiple in vitro assays and a mouse model.

METHODS

Human umbilical vein endothelial cells and mouse pulmonary endothelial cells (MPECs) were used for in vitro models to test the effect of anesthetics on endothelial permeability. The effect of anesthetics on pulmonary vascular leakage was analyzed using AngioSense 750 (PerkinElmer, USA) fluorescent tracer and rhodamine-labeled 3-kD dextran in a mouse model. Downstream targets were identified using RNA sequencing and confirmed by quantitative real-time polymerase chain reaction and Western blot.

RESULTS

Sevoflurane at clinically relevant concentrations disrupted the endothelial monolayer formed by human umbilical vein endothelial cells and MPECs in transwell permeability models. Sevoflurane, but not propofol, induced a 1.8-fold increase of AngioSense dye accumulation in mouse lung over control, indicating pulmonary vascular leakage in the sevoflurane group. RNA sequencing analysis, quantitative real-time polymerase chain reaction, and Western blot analysis revealed that sevoflurane induced the expression and activation of hypoxia-inducible factor 1α (HIF-1α) in vitro and in vivo . The activation of HIF-1α led to the increased expression of its downstream vascular endothelial growth factor (VEGF). The knockdown of HIF-1α restored the change of endothelial permeability and abolished the increase of VEGF induced by sevoflurane in MPECs.

CONCLUSIONS

The authors' results demonstrate that sevoflurane increased endothelial and pulmonary vascular permeability via HIF-1α and VEGF. Propofol had no significant effect on the permeability of endothelium.

Treg Cells Attenuate Pulmonary Venous Remodeling in PH-LHD via NLRC3 Signaling

BACKGROUND

Pulmonary venous remodeling is a key pathological feature of pulmonary hypertension associated with left heart disease (PH-LHD). This study aims to investigate the role of regulatory T (Treg) cells in this process.

METHODS

We used mouse models with transverse aortic constriction and cell depletion of Foxp3-DTR/tdTomato mice to examine Treg cells' function around pulmonary veins in PH-LHD in vivo. To confirm the effect of Nlrc3-/- Treg cells on PH-LHD, we utilized 3 mouse models: Nlrc3 knockout mice, athymic mice, and endothelial cell lineage tracing Cdh5CreERT2+/--mT/mG+/- mice. The interaction proteins and signaling pathways of Treg cells during endothelial-to-mesenchymal transition were elucidated by protein docking prediction, coimmunoprecipitation and cocultivation of Treg cells with venous endothelial cells.

RESULTS

Treg cells were abundant around pulmonary veins of transverse aortic constriction-induced PH-LHD and were essential for promoting inflammation resolution and inhibiting pulmonary venous remodeling. Nlrc3 expression was reduced in mice and patients with PH-LHD. NLRC3 (nucleotide-oligomerization domain-like receptor family CARD domain containing 3) deficiency inhibited Treg cell proliferation and impaired their immunosuppressive and endothelial-to-mesenchymal transition-protective effects. Mechanistically, NLRC3 interacted with TRAM (TRIF-related adaptor molecule) and regulated interferon regulatory factor 3 (IRF3)/NF-κB (nuclear factor-κB) p65 signaling in cluster differentiation 4+ (CD4+) T cells. NLRC3-deficient Treg cells promoted interleukin (IL)-18 expression through IRF3/NF-κB p65 signaling, and thus IL-18 secretion activated endothelial receptor tyrosine kinase (RTK) signaling, favoring endothelial-to-mesenchymal transition progression in pulmonary veins and PH-LHD progress. This process was reversible with IL-18 binding protein in vivo.

CONCLUSIONS

NLRC3 is crucial for Treg cells to prevent pulmonary venous remodeling in PH-LHD, primarily by modulating IL-18 secretion, which inhibits endothelial-to-mesenchymal transition and thereby improves disease progression and prognosis.

Targeting vascular endothelial growth receptor-2 (VEGFR-2): structural biology, functional insights, and therapeutic resistance

Angiogenesis, the process of new blood vessel formation, is a fundamental physiological process implicated in several pathological disorders. The vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are crucial for angiogenesis and vasculogenesis. Among them, the tyrosine kinase receptor VEGFR-2 is primarily expressed in endothelial cells (ECs). These cells regulate various physiological responses, including differentiation, cell proliferation, migration, and survival, by binding to VEGF mitogens. Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) is a key regulator of this process, making it a prime target for therapeutic intervention. Several drugs targeting VEGFR-2 have been approved and are currently utilized to halt the pathological axis of VEGF-VEGFR. This review will focus on the recent developments in the molecular structure and function of VEGFR-2, the molecular mechanism of VEGFR-2 activation, and its downstream signaling pathway. It will also discuss therapies and experimental drugs approved to inhibit the function of VEGFR-2 and the resistance mechanism.

Mechanism of pulmonary arterial vascular cell dysfunction in pulmonary hypertension in broiler chickens

Broiler ascites syndrome is a common and complex disease in broiler farming, which severely impacts broiler growth performance and health and brings huge economic losses to the breeding industry. Hypoxia has been shown to be an important cause of this disease. Prolonged exposure of broiler chickens to a hypoxic environment induces pulmonary vasoconstriction, which leads to an increase in pulmonary artery pressure, triggering pulmonary artery remodelling and compensatory right ventricular hypertrophy, and ultimately ascites. Pulmonary artery remodelling is a process in which the vascular wall tissue structure and function undergo pathological changes after the pulmonary artery is stimulated by various injuries or hypoxia, including endothelial dysfunction, abnormal proliferation of pulmonary artery smooth muscle cells, vascular fibrosis, etc. When these cells are damaged or stimulated, they may undergo programmed cell death, an orderly and regulated mode of cell death that is important for maintaining the stability of the body's internal environment. It has been demonstrated that death modes such as apoptosis and autophagy are involved in the pathophysiologic process of pulmonary hypertension, but their specific molecular mechanisms are still unclear. In this review, we first describe the pathogenesis of broiler ascites, then describe the specific mechanism of dysfunction of pulmonary artery vascular cells in broiler ascites syndrome, and finally elaborate the progression of different programmed cell death in broiler pulmonary hypertension. This study aims to elucidate the specific mechanisms underlying the dysfunction of pulmonary artery vascular cells in broiler pulmonary hypertension, thereby enhancing our understanding of the pathogenesis of this syndrome.

The sprouting angiogenesis and vascular dysfunction triggered by bisphenol S and tetrabromobisphenol S through disrupting vascular endothelial-cadherin in zebrafish

Exogenous chemical toxicants may be important inducers of pathological angiogenesis diseases. However, few studies have investigated the associations between pathological angiogenesis diseases and chemical toxicant exposures, and the specific mechanism by which chemical toxicants induce sprouting angiogenesis is unclear. In this study, zebrafish were exposed to bisphenol S (BPS, 1-100 μg/L) and tetrabromobisphenol S (TBBPS, 0.1 and 10 μg/L) from the embryonic stage to the larval stage to investigate how pollutants interfere with angiogenesis and the function of ectopic sprouting vessels. The results showed that BPS and TBBPS promoted ectopic sprouting angiogenesis in different types of vascular plexuses, including the posterior cardinal vein (PCV) and superficial choroidal vessels (SOVs), at different developmental time points. Proteomic analyses of eGFP-positive endothelial cells (ECs) isolated from Tg(flk1: eGFP) zebrafish revealed that both BPS and TBBPS induced ectopic angiogenesis by acting on vascular endothelial-cadherin (VE-cadherin) and activating downstream proangiogenic signaling. In ectopic sprouting vessels induced by BPS and TBBPS, increased endothelial permeability resulted in white blood cell recruitment. Human oxidized lipids also tended to deposit in these ectopic vessels following BPS and TBBPS exposure. These findings suggest that chemical toxicant-induced ectopic angiogenesis is an important cause of vascular dysfunction and related diseases.

Angiogenesis causes and vasculogenic mimicry formation in the context of cancer stem cells

Tumor occurrence, development, invasion, and metastasis are regulated by multiple mechanisms. Among these, angiogenesis promotes tumor progression mainly by supplying tumor tissue and providing channels for tumor metastasis. Cancer stem cells (CSCs) are another important factor affecting tumor progression by involving in tumor initiation and development, while remaining insensitive to conventional antitumor treatments. Among treatment strategies for them, owing to the existence of alternative angiogenic pathways or the risk of damaging normal stem cells, the clinical effect is not ideal. Angiogenesis and CSCs may influence each other in this process. Tumor angiogenesis can support CSC self-renewal by providing a suitable microenvironment, whereas CSCs can regulate tumor neovascularization and mediate drug resistance to anti-angiogenic therapy. This review summarized the role of vascular niche formed by angiogenesis in CSC self-renewal and stemness maintenance, and the function of CSCs in endothelial progenitor cell differentiation and pro-angiogenic factor upregulation. We also elucidated the malignant loop between CSCs and angiogenesis promoting tumor progression. Additionally, we summarized and proposed therapeutic targets, including blocking tumor-derived endothelial differentiation, inhibiting pro-angiogenic factor upregulation, and directly targeting endothelial-like cells comprising CSCs. And we analyzed the feasibility of these strategies to identify more effective methods to improve tumor treatment.

Endothelial-pericyte interactions regulate angiogenesis via VEGFR2 signaling during retinal development and disease

Pericytes stabilize the microvasculature by enhancing endothelial barrier integrity, resulting in functional networks. During retinal development, pericyte recruitment is crucial for stabilizing nascent angiogenic vasculature. However, in adulthood, disrupted endothelial-pericyte interactions lead to vascular dropout and pathological angiogenesis in ocular microvascular diseases, and strategies to stabilize the retinal vasculature are lacking. We demonstrate that direct endothelial-pericyte contact downregulates pVEGFR2 in endothelial cells, which enhances pericyte migration and promotes endothelial cell barrier function. Intravitreal injection of a VEGFR2 inhibitor in mouse models of the developing retina and oxygen-induced retinopathy increased pericyte recruitment and aided vascular stability. The VEGFR2 inhibitor further rescued ischemic retinopathy by enhancing vascularization and tissue growth while reducing vascular permeability. Our findings offer a druggable target to support the growth of functional and mature microvasculature in ocular microvascular diseases and tissue regeneration overall.

CPHNet: a novel pipeline for anti-HAPE drug screening via deep learning-based Cell Painting scoring

BACKGROUND

High altitude pulmonary edema (HAPE) poses a significant medical challenge to individuals ascending rapidly to high altitudes. Hypoxia-induced cellular morphological changes in the alveolar-capillary barrier such as mitochondrial structural alterations and cytoskeletal reorganization, play a crucial role in the pathogenesis of HAPE. These morphological changes are critical in understanding the cellular response to hypoxia and represent potential therapeutic targets. However, there is still a lack of effective and valid drug discovery strategies for anti-HAPE treatments based on these cellular morphological features. This study aims to develop a pipeline that focuses on morphological alterations in Cell Painting images to identify potential therapeutic agents for HAPE interventions.

METHODS

We generated over 100,000 full-field Cell Painting images of human alveolar adenocarcinoma basal epithelial cells (A549s) and human pulmonary microvascular endothelial cells (HPMECs) under different hypoxic conditions (1%~5% of oxygen content). These images were then submitted to our newly developed segmentation network (SegNet), which exhibited superior performance than traditional methods, to proceed to subcellular structure detection and segmentation. Subsequently, we created a hypoxia scoring network (HypoNet) using over 200,000 images of subcellular structures from A549s and HPMECs, demonstrating outstanding capacity in identifying cellular hypoxia status.

RESULTS

We proposed a deep neural network-based drug screening pipeline (CPHNet), which facilitated the identification of two promising natural products, ferulic acid (FA) and resveratrol (RES). Both compounds demonstrated satisfactory anti-HAPE effects in a 3D-alveolus chip model (ex vivo) and a mouse model (in vivo).

CONCLUSION

This work provides a brand-new and effective pipeline for screening anti-HAPE agents by integrating artificial intelligence (AI) tools and Cell Painting, offering a novel perspective for AI-driven phenotypic drug discovery.

Soluble E-cadherin contributes to inflammation in acute lung injury via VEGF/VEGFR2 signaling

As a gatekeeper of the airway epithelial cells, E-cadherin is not only a critical component for the maintenance of epithelial integrity, but also engaged in pathological processes through the release of a soluble form (sE-cadherin). This study was aimed to investigate the role of sE-cadherin in ALI/ARDS. Serum samples from patients with ARDS and healthy volunteers were collected for the detection of sE-cadherin. An LPS-induced mouse model was induced to analyze the expression of sE-cadherin, and a neutralizing antibody against sE-cadherin (DECMA-1) was given to the LPS-exposed mice. The effects of recombinant sE-cadherin were tested both in vitro and in vivo, and VEGFR2 inhibition was used to explore a possible mechanism for sE-cadherin-induced pulmonary inflammation. We observed an increased level of sE-cadherin in ARDS patients as well as in LPS-exposed mice. In vivo treatment of DECMA-1 significantly attenuated LPS-induced inflammation. In vitro, exogenous sE-cadherin can dramatically upregulate the expression of VEGF in THP1-derived macrophages and human primary macrophages. In addition, intratracheal instillation of recombinant sE-cadherin leads to significant increased infiltration of neutrophils as well as overproduction of IL-6 and IL1β, which could be attenuated by inhibition of VEGF/VEGFR2 signaling. While blockade of the VEGF/VEGFR2 pathway inhibited pulmonary inflammatory responses in LPS-exposed mice. Taken together, our data demonstrated that sE-cadherin contributes to lung inflammation in ALI/ARDS, which is related to activation of the VEGF/VEGFR2 pathway.

Mechanistic insights into the role of EGLN3 in pulmonary vascular remodeling and endothelial dysfunction

Endothelial dysfunction is a pivotal initiating factor in vascular remodeling in pulmonary hypertension. EGLN3, a hypoxia response factor, plays a significant role in cell proliferation and angiogenesis, which are closely related to the pathophysiological conditions of pulmonary hypertension. This study investigates the potential involvement of EGLN3 in the injury response of pulmonary vascular endothelial cells and its contribution to the development of pulmonary arterial hypertension. Research has demonstrated that in patients with pulmonary arterial hypertension and various animal models of the condition, EGLN3 expression is upregulated in the remodeled pulmonary artery endothelium. Notably, the endothelial cell-specific knockout of EGLN3 can decelerate the progression of pulmonary arterial hypertension, whereas its overexpression has the opposite effect. Mechanistic analyses reveal that under hypoxic conditions, JUN initiates the transcription of EGLN3 by binding to its promoter region. Subsequently, EGLN3 interacts with HUR to enhance the stability of EGFR mRNA, thereby activating the PI3K/AKT and MAPK signaling pathways, which ultimately results in endothelial cell damage, proliferation, and migration. These findings suggest that EGLN3 is a critical gene for maintaining endothelial function and vascular homeostasis and holds promise as a novel therapeutic target for the treatment of pulmonary hypertension.

Multi-omics analysis reveals that neutrophil extracellular traps related gene TIMP1 promotes CRC progression and influences ferroptosis

BACKGROUND

Previous studies have found that neutrophil extracellular traps (NETs) are highly expressed in colorectal cancer (CRC) and are associated with poor prognosis. Currently, there are few studies on the relationship between NETs and CRC, so we tried to explore new markers based on NETs to assist in the treatment of CRC.

METHOD

We jointly screened three major NETs genes through machine learning. Large-sample RNA transcriptome and single-cell transcriptome analysis further confirmed that TIMP1 is a core gene in NETs. We used small interfering RNA to knockdown TIMP1, and verified the ability of TIMP1 in CRC proliferation, invasion and migration through western blot, transwell, cell scratch assay, cell clone formation and other experiments.

RESULT

We screened out three major NETs Genes: TIMP1, F3, and CRISPLD2 based on machine learning. The NETs score constructed based on this not only predicts the prognosis of CRC patients but also shows significant differences in MSI status, chenckpoints expression, and predicted efficacy of PD-L1 targeted therapy. Transcriptome and single-cell data reveal that TIMP1 is highly expressed in neutrophils and is associated with poor prognosis in colorectal cancer patients and the occurrence of ferroptosis. Biological experiments have proven that TIMP1 can promote the proliferation, invasion and migration of CRC.

CONCLUDE

Bioinformatics analysis combined with experimental verification showed that TIMP1 is related to ferroptosis and plays a promoting role in the invasion, migration and proliferation of CRC.

Keeping the Ductus Arteriosus Patent: Current Strategy and Perspectives

Patent ductus arteriosus (PDA) continues to be a significant finding among infants, as well as adults. What is widely considered to be a problem though, in a group of patients with congenital heart disease, it is the only lifeline. We will initially study the anatomical and biochemical mechanisms affecting the PDA. The main focus of this review is on ductal-dependent congenital heart disease and biochemical and pharmacological approaches to maintaining ductus arteriosus patency, as well as surgical and interventional options for maintaining circulation. The present review aims to highlight gaps in the knowledge regarding the multifunctional role of ductus arteriosus endothelium and possibly propose a new approach to pharmacological maintenance of ductus arteriosus patency.

PCDH17 induces colorectal cancer metastasis by destroying the vascular endothelial barrier

Compromised vascular integrity facilitates the cancer cells extravasation and metastasis. However, the mechanisms leading to a disruption in vascular integrity in colorectal cancer (CRC) remain unclear. In this study, PCDH17 expression was higher in the vascular endothelial cells of colon cancer with distant metastasis, and the rates of PCDH17+ endothelial cells (ECs) was associated with the M stage in clinical pathological characteristics analysis and correlated with a poor survival prognosis. The liver and lung metastatic dissemination of MC-38 was significantly decreased in PCDH17-/-mice. The ubiquitination and degradation of VEGFR2 was prevented by the interaction between PCDH17 and the E3 ubiquitin ligase MARCH5, which causing the separation of internalized VE-cadherin, and increased the vascular permeability and metastasis of CRC. These results highlight the importance of PCDH17 in maintaining vascular integrity, which has emphasis for endothelial barrier function in metastatic cancer. PCDH17 has the potential to be a marker for predicting tumor metastasis as well as a viable treatment target for CRC.

Relevance of the GH-VEGFB/VEGFA axis in liver grafts from brain-dead donors with alcohol-associated liver disease

Introduction

Grafts with alcohol-associated liver disease (ALD) subjected to prolonged cold ischaemia from donors after brain death (DBD) are typically unsuitable for transplantation. Here, we investigated the role of growth hormone (GH) in livers with ALD from DBDs and its relationship with vascular endothelial growth factor A (VEGFA) and VEGFB.

Methods

Livers from rats fed ethanol for 6 weeks and with brain death (BD) were cold stored for 24 h and subjected to ex vivo reperfusion. Hepatic damage and proliferative and inflammatory parameters were analysed after BD, before graft retrieval, and after reperfusion. Survival was monitored using an in vivo transplantation model.

Results

In DBDs, the administration of GH, which increased the levels in the intestine but not in the liver, induced the generation of both VEGFA and VEGFB in the intestine and protected against hepatic damage caused by BD before retrieving liver grafts from donors. However, VEGFA was the only factor that protected against damage after cold ischemia and reperfusion, which also increased the survival of the recipients.

Discussion

In conclusion, the signalling pathway and beneficial properties of the GH-VEGFA/VEGFB pathway, in which the intestine-liver axis plays a key role, were disrupted when grafts with ALD from DBDs were retrieved from donors and subjected to cold ischemia and reperfusion.

Lactobacillus reuteri Alleviates Hyperoxia-Induced BPD by Activating IL-22/STAT3 Signaling Pathway in Neonatal Mice

Bronchopulmonary dysplasia (BPD) is the most common chronic respiratory disease in preterm infants. Little is known about the regulatory effect of lung Lactobacillus and its mechanism in BPD. This study explored the effect of L. reuteri on hyperoxia-induced mice lung injuries and examined whether L. reuteri played a role via the IL-22/STAT3 pathway. We found that the intranasal administration of L. reuteri and its tryptophan metabolite indole-3-aldehyde (3-IAld) ameliorated hyperoxia-induced mice lung BPD-like changes, deceased proinflammatory cytokines (IL-1β, IL-6, and TNF-α), and increased the levels of surfactant-associated protein C (SPC), aquaporin 5 (AQP5), and vascular endothelial growth factor receptor 2 (VEGFR2, also known as FLK-1). Furthermore, L. reuteri and 3-IAld increased the expression of IL-22. IL-22 was also confirmed to ameliorate hyperoxia-induced mice lung pathological changes, and the protective effects of L. reuteri could be inhibited by anti-IL-22 neutralizing antibody. Finally, we confirmed STAT3 activation by IL-22 in MLE-12 cells. In summary, our study confirmed L. reuteri alleviated hyperoxia-induced lung BPD-like changes in mice by activating the IL-22/STAT3 signaling pathway via IL-22 production. Probiotics Lactobacillus is a potential treatment for hyperoxia-induced lung injury in newborns.

Exploring the bidirectional causal association between Sleep Apnea Syndrome and Depression: A Mendelian randomization study involving gut microbiota, serum metabolites, and inflammatory factors

OBJECTIVE

This study aimed to investigate the potential causal association between Sleep Apnea Syndrome (SAS) and Depression, focusing on the roles of gut microbiota, serum metabolites, and inflammatory factors in these conditions.

METHODS

Mendelian Randomization (MR) analysis was performed using data from genome-wide association studies to assess 211 types of gut microbiota, 1400 serum metabolites, and 91 inflammatory factors as potential contributing factors. Causal inference was conducted using the Inverse Variance Weighted (IVW) method, with additional robustness checks through Cochran's Q test, MR-Egger regression intercept test, MR-PRESSO global test, and leave-one-out analysis.

RESULTS

The MR analysis indicated a positive correlation between the risk of SAS and Depression (OR = 1.12, 95 % CI: 1.05-1.19, P < 0.001), with a reciprocal analysis showing a similar positive correlation between Depression and the risk of SAS (OR = 1.19, 95 % CI: 1.07-1.31, P = 0.001). Additionally, causal associations were identified between 15 types of gut microbiota, 36 serum metabolites, and 2 inflammatory factors with SAS, and between 11 types of gut microbiota, 23 serum metabolites, and 3 inflammatory factors with Depression (IVW, all P < 0.05). The robustness of these findings was confirmed through the MR-Egger regression intercept test and MR-PRESSO global test.

CONCLUSION

This study provides epidemiological evidence of a bidirectional causal association between SAS and Depression, emphasizing the potential roles of gut microbiota, serum metabolites, and inflammatory factors in the pathogenesis of these disorders. These findings may inform the development of new therapeutic strategies.

Regulatory roles of RNA methylation in vascular lesions in ocular and cardiopulmonary diseases

RNA methylation is a widespread regulatory mechanism that controls gene expression in physiological processes. In recent years, the mechanisms and functions of RNA methylation under diseased conditions have been increasingly unveiled by RNA sequencing technologies with large scale and high resolution. In this review, the fundamental concept of RNA methylation is introduced, and the common types of transcript methylation and their machineries are described. Then, the regulatory roles of RNA methylation, particularly N6-methyladenosine and 5-methylcytosine, in the vascular lesions of ocular and cardiopulmonary diseases are discussed and compared. The ocular diseases include corneal neovascularization, retinopathy of prematurity, diabetic retinopathy, and pathologic myopia; whereas the cardiopulmonary ailments involve atherosclerosis and pulmonary hypertension. This review hopes to shed light on the common regulatory mechanisms underlying the vascular lesions in these ocular and cardiopulmonary diseases, which may be conducive to developing therapeutic strategies in clinical practice.

Plasma exosomes from patients with coronary artery disease promote atherosclerosis via impairing vascular endothelial junctions

The underlying mechanism of vascular endothelial hyperpermeability caused by decrease of endothelial junctions occurring in atherosclerosis remains elusive. Our findings identified that plasma exosomes from patients with stable coronary artery disease (ExoSCAD) contain differentially expressed miRNAs that are clustered with genes related to cell junctions, prompting us to investigate the role of ExoSCAD in regulating vascular endothelial junctions and to elucidate the underlying mechanisms. Here, we show that ExoSCAD markedly impair vascular endothelial junctions via suppressing VE-Cadherin and ZO-1 in endothelial cells in vitro and in vivo, consequently increases endothelial permeability. Critically, exosomal miR-140-3p plays a crucial role in ExoSCAD-induced inhibition of ZO-1, and may be an important causative factor in the development of endothelial hyperpermeability during atherosclerosis. Additionally, exosomal miR-140-3p level coordinates with severity of SCAD. Targeting miR-140-3p in circulating exosomes might open novel options for treatment of atherosclerosis.

Searching for Old and New Small-Molecule Protein Kinase Inhibitors as Effective Treatments in Pulmonary Hypertension-A Systematic Review

Treatment options for pulmonary arterial hypertension (PAH) have improved substantially in the last 30 years, but there is still a need for novel molecules that can regulate the excessive accumulation of pulmonary artery smooth muscle cells (PASMCs) and consequent vascular remodeling. One set of possible candidates are protein kinases. The study provides an overview of existing preclinical and clinical data regarding small-molecule protein kinase inhibitors in PAH. Online databases were searched from 2001 to 2023 according to PRISMA. The corpus included preclinical studies demonstrating alterations in at least one PH-related parameter following chronic exposure to an individual protein kinase inhibitor, as well as prospective clinical reports including healthy adults or those with PAH, with primary outcomes defined as safety or efficacy of an individual small-molecule protein kinase inhibitor. Several models in preclinical protocols (93 papers) have been proposed for studying small-molecule protein kinase inhibitors in PAH. In total, 51 kinase inhibitors were tested. Meta-analysis of preclinical results demonstrated seralutinib, sorafenib, fasudil hydrochloride, and imatinib had the most comprehensive effects on PH with anti-inflammatory, anti-oxidant, and anti-proliferative potential. Fasudil demonstrated more than 70% animal survival with the longest experimental period, while dasatinib, nintedanib, and (R)-crizotinib could deteriorate PAH. The substances targeting the same kinases often varied considerably in their activity, and such heterogeneity may be due to the variety of causes. Recent studies have addressed the molecules that affect multiple networks such as PDG-FRα/β/CSF1R/c-KIT/BMPR2 or FKBP12/mTOR. They also focus on achieving a satisfactory safety profile using innovative inhalation formulations Many small-molecule protein kinase inhibitors are able to control migration, proliferation and survival in PASMCs in preclinical observations. Standardized animal models can successfully reduce inter-study heterogeneity and thereby facilitate successful identification of candidate drugs for further evaluations.

Correlation between pre-operative VE-cadherin and DLL4 and the maturation after primary arteriovenous fistula in uremic patients

Aims

Uremic patients require dialysis to replace the declined kidney function, and arteriovenous fistula (AVF) is a commonly used dialysis access route. Our study aimed to explore vascular endothelial cells cadherin (VE-cadherin) and Delta-like ligand 4 (DLL4) expression in uremic patients undergoing primary AVF surgery and their correlation with AVF maturation.

Methods

We conducted a prospective study that included n = 55 voluntary uremic patients receiving their initial AVF procedure for renal replacement therapy, subjects were divided into a mature group and a failure group based on whether the AVF matured within 3 months post-operatively. We analyzed the association of VE-cadherin and DLL4 with AVF maturation by examining their expression levels in serum and the endothelium of cephalic veins.

Results

Pre-operative serum VE-cadherin, in the mature group measured 125.07 (106.77-167.65) ng/L, and DLL4 was 92.78 (83.83-106.72) pg/mL, while the failure group had VE-cadherin at 95.40 (79.03-107.16) ng/L (P = 0.001), and DLL4 at 60.42 (43.98-80.15) pg/mL with a statistical significant; (P = 0.002), binary logistic regression analysis indicated a significant association between cephalic vein diameter, VE-cadherin, DLL4 levels, and AVF immaturity (P = 0.024, P = 0.014 respectively). Immunohistochemical staining showed slightly higher VE-cadherin levels in the mature group than in the failure group (P = 0.366). DLL4 was primarily located in the cell membrane and cytoplasm, concentrated in the inner membrane, with significantly higher levels in the mature group compared to the failure group (P = 0.027).

Conclusion

The failure group exhibited lower levels of VE-cadherin and DLL4 in serum and vascular tissue, these results suggest that VE-cadherin and DLL4 might play pivotal regulatory roles in the onset and the progression of fistula immaturity, potentially serving as promising targets for future interventions.

BNIP3+ fibroblasts associated with hypoxia and inflammation predict prognosis and immunotherapy response in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors that lacks effective treatment options. Cancer-associated fibroblasts (CAFs), an important component of the tumor microenvironment, associated with tumor progression, prognosis, and treatment response. This work aimed to explore the novel CAFs-associated target to improve treatment strategies in PDAC.

METHODS

The PDAC single-cell sequencing data (CRA001160, n = 35) were downloaded and integrated based on GSA databases to classify fibroblasts into fine subtypes. Functional enrichment analysis and coexpression regulatory network analysis were used to identify the functional phenotypes and biological properties of the different fibroblast subtypes. Fibroblast differentiation trajectories were constructed using pseudochronological analysis to identify initial and terminally differentiated subtypes of fibroblasts. The changes in the proportions of different fibroblast subtypes before and after PDAC immunotherapy were compared in responsive and nonresponding patients, and the relationships between fibroblast subtypes and PDAC immunotherapy responsiveness were determined based on GSA and GEO database. Using molecular biology methods to confirm the effects of BNIP3 on hypoxia and inflammation in CAFs. CAFs were co cultured with pancreatic cancer cells to detect their effects on migration and invasion of pancreatic cancer.

RESULTS

Single-cell data analysis divided fibroblasts into six subtypes. The differentiation trajectory suggested that BNIP3+ Fibro subtype exhibited terminal differentiation, and the expression of genes related to hypoxia and the inflammatory response increased gradually with differentiation time. The specific overexpressed genes in the BNIP3+ Fibro subtype were significantly associated with overall and disease progression-free survival in the patients with PDAC. Interestingly, the greater the proportion of the BNIP3+ Fibro subtype was, the worse the response of PDAC patients to immunotherapy, and the CRTL treatment regimen effectively reduced the proportion of the BNIP3+ Fibro subtype. After knocking out BNIP3, the hypoxia markers and inflammatory factors of CAFs were inhibited. Co-culture of CAFs with pancreatic cancer cells can increase the migration and invasion of pancreatic cancer, but this could be reversed by knocking out BNIP3.

CONCLUSIONS

This study revealed the BNIP3+ Fibro subtype associated with hypoxia and inflammatory responses, which was closely related to the poor prognosis of patients with PDAC, and identified signature genes that predict the immunotherapy response in PDAC.

Chitosan-based biomaterial delivery strategies for hepatocellular carcinoma

Background

Hepatocellular carcinoma accounts for 80% of primary liver cancers, is the most common primary liver malignancy. Hepatocellular carcinoma is the third leading cause of tumor-related deaths worldwide, with a 5-year survival rate of approximately 18%. Chemotherapy, although commonly used for hepatocellular carcinoma treatment, is limited by systemic toxicity and drug resistance. Improving targeted delivery of chemotherapy drugs to tumor cells without causing systemic side effects is a current research focus. Chitosan, a biopolymer derived from chitin, possesses good biocompatibility and biodegradability, making it suitable for drug delivery. Enhanced chitosan formulations retain the anti-tumor properties while improving stability. Chitosan-based biomaterials promote hepatocellular carcinoma apoptosis, exhibit antioxidant and anti-inflammatory effects, inhibit tumor angiogenesis, and improve extracellular matrix remodeling for enhanced anti-tumor therapy.

Methods

We summarized published experimental papers by querying them.

Results and Conclusions

This review discusses the physicochemical properties of chitosan, its application in hepatocellular carcinoma treatment, and the challenges faced by chitosan-based biomaterials.

Enhancing the Inhibition of Corneal Neovascularization Efficacy by Self-Assembled into Supramolecular Hydrogel of Anti-Angiogenic Peptide

Background

Corneal neovascularization (CNV) is a common eye disease that leads to blindness. New treatment strategies are urgently needed due to the limitations of current treatment methods.

Methods

We report the synthesis of peptide Nap-FFEEPCAIWF ( Comp.3 ) via chemical conjugation of Nap-FFEE ( Comp.2 ) to antiangiogenic peptide PCAIWF (Comp.1). Comp.3 self-assembled into a hydrogel ( gel of 3 ) composed of nanofibers, which enhanced the antiangiogenic function of the epitope.

Results

We developed a novel peptide with an amphiphilic framework, Comp.3 , which could self-assemble into a supramolecular hydrogel with a well-ordered nanofiber structure. The nanofibers exhibited good biocompatibility with corneal epithelial cells, presenting a promising strategy to enhance the efficacy of free peptide-based drugs in the treatment of ocular vascular diseases, such as CNV and other angiogenesis-related diseases.

Conclusion

Nap-FFEEPCAIWF nanofibers provide an alternative approach to enhancing the therapeutic efficiency of free peptide-based drugs against ocular vascular diseases.

Synergistic promotion of angiogenesis after intracerebral hemorrhage by ginsenoside Rh2 and chrysophanol in rats

BACKGROUND

Intracerebral hemorrhage (ICH) is a debilitating condition characterized by the rupture of cerebral blood vessels, resulting in profound neurological deficits. A significant challenge in the treatment of ICH lies in the brain's limited capacity to regenerate damaged blood vessels. This study explores the potential synergistic effects of Ginsenoside Rh2 and Chrysophanol in promoting angiogenesis following ICH in a rat model.

METHODS

Network pharmacology was employed to predict the potential targets and pathways of Ginsenoside Rh2 and Chrysophanol for ICH treatment. Molecular docking was utilized to assess the binding affinity between these compounds and their respective targets. Experimental ICH was induced in male Sprague-Dawley rats through stereotactic injection of type VII collagenase into the right caudate putamen (CPu). The study encompassed various methodologies, including administration protocols, assessments of neurological function, magnetic resonance imaging, histological examination, observation of brain tissue ultrastructure, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), immunofluorescence staining, Western blot analysis, and statistical analyses.

RESULTS

Network pharmacology analysis indicated that Ginsenoside Rh2 and Chrysophanol may exert their therapeutic effects in ICH by promoting angiogenesis. Results from animal experiments revealed that rats treated with Ginsenoside Rh2 and Chrysophanol exhibited significantly improved neurological function, reduced hematoma volume, and diminished pathological injury compared to the Model group. Immunofluorescence analysis demonstrated enhanced expression of vascular endothelial growth factor receptor 2 (VEGFR2) and CD31, signifying augmented angiogenesis in the peri-hematomal region following combination therapy. Importantly, the addition of a VEGFR2 inhibitor reversed the increased expression of VEGFR2 and CD31. Furthermore, Western blot analysis revealed upregulated expression of angiogenesis-related factors, including VEGFR2, SRC, AKT1, MAPK1, and MAPK14, in the combination therapy group, but this effect was abrogated upon VEGFR2 inhibitor administration.

CONCLUSION

The synergistic effect of Ginsenoside Rh2 and Chrysophanol demonstrated a notable protective impact on ICH injury in rats, specifically attributed to their facilitation of angiogenesis. Consequently, this research offers a foundation for the utilization of Ginsenosides Rh2 and Chrysophanol in medical settings and offers direction for the advancement of novel pharmaceuticals for the clinical management of ICH.

Upregulation of eIF2α by m6A modification accelerates the proliferation of pulmonary artery smooth muscle cells in MCT-induced pulmonary arterial hypertension rats

Pulmonary arterial hypertension (PAH) is a malignant cardiovascular disease. Eukaryotic initiation factor 2α (eIF2α) plays an important role in the proliferation of pulmonary artery smooth muscle cells (PASMCs) in hypoxia-induced pulmonary hypertension (HPH) rats. However, the regulatory mechanism of eIF2α remains poorly understood in PAH rats. Here, we discover eIF2α is markedly upregulated in monocrotaline (MCT)-induced PAH rats, eIF2α can be upregulated by mRNA methylation, and upregulated eIF2α can promote PASMC proliferation in MCT-PAH rats. GSK2606414, eIF2α inhibitor, can downregulate the expression of eIF2α and alleviate PASMC proliferation in MCT-PAH rats. And we further discover the mRNA of eIF2α has a common sequence with N 6-methyladenosine (m6A) modification by bioinformatics analysis, and the expression of METTL3, WTAP, and YTHDF1 is upregulated in MCT-PAH rats. These findings suggest a potentially novel mechanism by which eIF2α is upregulated by m6A modification in MCT-PAH rats, which is involved in the pathogenesis of PAH.

Functional EPAS1/HIF2A missense variant is associated with hematocrit in Andean highlanders

Hypoxia-inducible factor pathway genes are linked to adaptation in both human and nonhuman highland species. EPAS1, a notable target of hypoxia adaptation, is associated with relatively lower hemoglobin concentration in Tibetans. We provide evidence for an association between an adaptive EPAS1 variant (rs570553380) and the same phenotype of relatively low hematocrit in Andean highlanders. This Andean-specific missense variant is present at a modest frequency in Andeans and absent in other human populations and vertebrate species except the coelacanth. CRISPR-base-edited human cells with this variant exhibit shifts in hypoxia-regulated gene expression, while metabolomic analyses reveal both genotype and phenotype associations and validation in a lowland population. Although this genocopy of relatively lower hematocrit in Andean highlanders parallels well-replicated findings in Tibetans, it likely involves distinct pathway responses based on a protein-coding versus noncoding variants, respectively. These findings illuminate how unique variants at EPAS1 contribute to the same phenotype in Tibetans and a subset of Andean highlanders despite distinct evolutionary trajectories.

Activation of Src Kinase Mediates the Disruption of Adherens Junction in the Blood-labyrinth Barrier after Acoustic Trauma

BACKGROUND

Adherens junction in the blood-labyrinth barrier is largely unexplored because it is traditionally thought to be less important than the tight junction. Since increasing evidence indicates that it actually functions upstream of tight junction adherens junction may potentially be a better target for ameliorating the leakage of the blood-labyrinth barrier under pathological conditions such as acoustic trauma.

AIMS

This study was conducted to investigate the pathogenesis of the disruption of adherens junction after acoustic trauma and explore potential therapeutic targets.

METHODS

Critical targets that regulated the disruption of adherens junction were investigated by techniques such as immunofluorescence and Western blotting in C57BL/6J mice.

RESULTS

Upregulation of Vascular Endothelial Growth Factor (VEGF) and downregulation of Pigment Epithelium-derived Factor (PEDF) coactivated VEGF-PEDF/VEGF receptor 2 (VEGFR2) signaling pathway in the stria vascularis after noise exposure. Downstream effector Src kinase was then activated to degrade VE-cadherin and dissociate adherens junction, which led to the leakage of the blood-labyrinth barrier. By inhibiting VEGFR2 or Src kinase, VE-cadherin degradation and blood-labyrinth barrier leakage could be attenuated, but Src kinase represented a better target to ameliorate blood-labyrinth barrier leakage as inhibiting it would not interfere with vascular endothelium repair, neurotrophy and pericytes proliferation mediated by upstream VEGFR2.

CONCLUSION

Src kinase may represent a promising target to relieve noise-induced disruption of adherens junction and hyperpermeability of the blood-labyrinth barrier.

Tom70-regulated mitochondrial biogenesis via TFAM improves hypoxia-induced dysfunction of pulmonary vascular endothelial cells and alleviates hypoxic pulmonary hypertension

BACKGROUND

Hypoxic pulmonary hypertension (HPH) is a common type of pulmonary hypertension and characterized by pulmonary vascular remodeling and constriction. A large number of studies have shown that pulmonary vascular endothelial cells (PVECs) dysfunction plays an important role in the initiation and development stages of HPH, but the mechanism of PVECs dysfunction after hypoxia remains unclear. In this study, we explored the exact mechanism of PVECs dysfunction after hypoxia.

METHODS

In vitro, we used primary cultured PVECs hypoxia model to mimic HPH injury. We detected the expressions of mitochondrial biogenesis markers, mitochondrial transcription factor A (TFAM) level inside mitochondria, mitochondrial quantity and function, and the components expressions of translocase of outer mitochondrial membrane (TOM) at 24 h after hypoxia. To explore the effects of Tom70 on mitochondrial biogenesis and functions of PVECs after hypoxia, Tom70 overexpression adenovirus was constructed, and the expressions of mitochondrial biogenesis markers, TFAM level inside mitochondria, mitochondrial quantity and function, and the functions of PVECs were detected. And in vivo, we used cre-dependent overexpression adenovirus of Tom70 in the Cdh5-CreERT2 mouse model of HPH to verify the role of upregulating PVECs Tom70 in improving HPH.

RESULTS

Hypoxia obviously increased the expressions of mitochondrial biogenesis markers for PGC-1α, NRF-1 and TFAM, but reduced the content of TFAM in mitochondria and the quantity and functions of mitochondria. In addition, only Tom70 expression among the TOM components was significantly decreased after hypoxia, and up-regulation of Tom70 significantly increased the content of TFAM in mitochondria of PVECs by transporting TFAM into mitochondria after hypoxia, enhanced the quantity and functions of mitochondria, improved the functions of PVECs, and ultimately alleviated HPH.

CONCLUSION

The findings of present study demonstrated that hypoxia induced the decreased expression of Tom70 in PVECs, reduced the mitochondrial biogenesis-associated TFAM protein transporting into mitochondria, inhibited mitochondrial biogenesis, caused PVECs injury, and prompted the formation of HPH. However, up-regulation of Tom70 abolished the hypoxia-induced injurious effects on PVECs and alleviated HPH.

BCLAF1-induced HIF-1α accumulation under normoxia enhances PD-L1 treatment resistances via BCLAF1-CUL3 complex

Bcl-2-associated transcription factor-1 (BCLAF1), an apoptosis-regulating protein of paramount significance, orchestrates the progression of various malignancies. This study reveals increased BCLAF1 expression in hepatocellular carcinoma (HCC) patients, in whom elevated BCLAF1 levels are linked to escalated tumor grades and diminished survival rates. Moreover, novel BCLAF1 expression is particularly increased in HCC patients who were not sensitive to the combined treatment of atezolizumab and bevacizumab, but not in patients who had tumors that responded to the combined regimen. Notably, overexpression of BCLAF1 increases HCC cell proliferation in vitro and in vivo, while the conditioned medium derived from cells overexpressing BCLAF1 strikingly enhances the tube-formation capacity of human umbilical vein endothelial cells. Furthermore, compelling evidence demonstrates that BCLAF1 attenuates the expression of prolyl hydroxylase domain protein 2 (PHD2) and governs the stability of hypoxia-inducible factor-1α (HIF-1α) under normoxic conditions without exerting any influence on transcription, as determined by Western blot and RT‒qPCR analyses. Subsequently, employing coimmunoprecipitation and immunofluorescence, we validated the reciprocal interaction between BCLAF1 and Cullin 3 (CUL3), through which BCLAF1 actively upregulates the ubiquitination and degradation of PHD2. The Western blot and RT‒qPCR results suggests that programmed death ligand-1 (PD-L1) is one of the downstream responders to HIF-1α in HCC. Thus, we reveal the pivotal role of BCLAF1 in promoting PD-L1 transcription and, through binding to CUL3, in promoting the accumulation of HIF-1α under normoxic conditions, thereby facilitating the ubiquitination and degradation of PHD2.

Pentastatin, a matrikine of the collagen IVα5, is a novel endogenous mediator of pulmonary endothelial dysfunction

Deposition of basement membrane components, such as collagen IVα5, is associated with altered endothelial cell function in pulmonary hypertension. Collagen IVα5 harbors a functionally active fragment within its C-terminal noncollageneous (NC1) domain, called pentastatin, whose role in pulmonary endothelial cell behavior remains unknown. Here, we demonstrate that pentastatin serves as a mediator of pulmonary endothelial cell dysfunction, contributing to pulmonary hypertension. In vitro, treatment with pentastatin induced transcription of immediate early genes and proinflammatory cytokines and led to a functional loss of endothelial barrier integrity in pulmonary arterial endothelial cells. Mechanistically, pentastatin leads to β1-integrin subunit clustering and Rho/ROCK activation. Blockage of the β1-integrin subunit or the Rho/ROCK pathway partially attenuated the pentastatin-induced endothelial barrier disruption. Although pentastatin reduced the viability of endothelial cells, smooth muscle cell proliferation was induced. These effects on the pulmonary vascular cells were recapitulated ex vivo in the isolated-perfused lung model, where treatment with pentastatin-induced swelling of the endothelium accompanied by occasional endothelial cell apoptosis. This was reflected by increased vascular permeability and elevated pulmonary arterial pressure induced by pentastatin. This study identifies pentastatin as a mediator of endothelial cell dysfunction, which thus might contribute to the pathogenesis of pulmonary vascular disorders such as pulmonary hypertension.NEW & NOTEWORTHY This study is the first to show that pentastatin, the matrikine of the basement membrane (BM) collagen IVα5 polypeptide, triggers rapid pulmonary arterial endothelial cell barrier disruption, activation, and apoptosis in vitro and ex vivo. Mechanistically, pentastatin partially acts through binding to the β1-integrin subunit and the Rho/ROCK pathway. These findings are the first to link pentastatin to pulmonary endothelial dysfunction and, thus, suggest a major role for BM-matrikines in pulmonary vascular diseases such as pulmonary hypertension.

Roxadustat promotes hypoxia-inducible factor-1α/vascular endothelial growth factor signalling to enhance random skin flap survival in rats

Random skin flaps have limited clinical application as a broad surgical reconstruction treatment because of distal necrosis. The prolyl hydroxylase domain-containing protein inhibitor roxadustat (RXD) enhances angiogenesis and reduces oxidative stress and inflammation. This study explored the function of RXD in the survival of random skin flaps. Thirty-six male Sprague-Dawley rats were randomly divided into low-dose RXD group (L-RXD group, 10 mg/kg/2 day), high-dose RXD group (H-RXD group, 25 mg/kg/2 day), and control group (1 mL of solvent, 1:9 DMSO:corn oil). The proportion of surviving flaps was determined on day 7 after surgery. Angiogenesis was assessed by lead oxide/gelatin angiography, and microcirculation blood perfusion was evaluated by laser Doppler flow imaging. Specimens in zone II were obtained, and the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured as indicators of oxidative stress. Histopathological status was evaluated with haematoxylin and eosin staining. The levels of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), and the inflammatory factors interleukin (IL)-1β, IL-6, and tumour necrosis factor-α (TNF-α) were detected by immunohistochemistry. RXD promoted flap survival and microcirculatory blood perfusion. Angiogenesis was detected distinctly in the experimental group. SOD activity increased and the MDA level decreased in the experimental group. Immunohistochemistry indicated that the expression levels of HIF-1α and VEGF were increased while the levels of IL-6, IL-1β, and TNF-α were decreased after RXD injection. RXD promoted random flap survival by reinforcing vascular hyperplasia and decreasing inflammation and ischaemia-reperfusion injury.

Sex-biased TGFβ signalling in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a rare cardiovascular disorder leading to pulmonary hypertension and, often fatal, right heart failure. Sex differences in PAH are evident, which primarily presents with a female predominance and increased male severity. Disturbed signalling of the transforming growth factor-β (TGFβ) family and gene mutations in the bone morphogenetic protein receptor 2 (BMPR2) are risk factors for PAH development, but how sex-specific cues affect the TGFβ family signalling in PAH remains poorly understood. In this review, we aim to explore the sex bias in PAH by examining sex differences in the TGFβ signalling family through mechanistical and translational evidence. Sex hormones including oestrogens, progestogens, and androgens, can determine the expression of receptors (including BMPR2), ligands, and soluble antagonists within the TGFβ family in a tissue-specific manner. Furthermore, sex-related genetic processes, i.e. Y-chromosome expression and X-chromosome inactivation, can influence the TGFβ signalling family at multiple levels. Given the clinical and mechanistical similarities, we expect that the conclusions arising from this review may apply also to hereditary haemorrhagic telangiectasia (HHT), a rare vascular disorder affecting the TGFβ signalling family pathway. In summary, we anticipate that investigating the TGFβ signalling family in a sex-specific manner will contribute to further understand the underlying processes leading to PAH and likely HHT.

Advances in the research of sulfur dioxide and pulmonary hypertension

Pulmonary hypertension (PH) is a fatal disease caused by progressive pulmonary vascular remodeling (PVR). Currently, the mechanisms underlying the occurrence and progression of PVR remain unclear, and effective therapeutic approaches to reverse PVR and PH are lacking. Since the beginning of the 21st century, the endogenous sulfur dioxide (SO2)/aspartate transaminase system has emerged as a novel research focus in the fields of PH and PVR. As a gaseous signaling molecule, SO2 metabolism is tightly regulated in the pulmonary vasculature and is associated with the development of PH as it is involved in the regulation of pathological and physiological activities, such as pulmonary vascular cellular inflammation, proliferation and collagen metabolism, to exert a protective effect against PH. In this review, we present an overview of the studies conducted to date that have provided a theoretical basis for the development of SO2-related drug to inhibit or reverse PVR and effectively treat PH-related diseases.

Inhibition of LPA-LPAR1 and VEGF-VEGFR2 Signaling in IPF Treatment

Due to the complex mechanism and limited treatments available for pulmonary fibrosis, the development of targeted drugs or inhibitors based on their molecular mechanisms remains an important strategy for prevention and treatment. In this paper, the downstream signaling pathways mediated by VEGFR and LPAR1 in pulmonary cells and the role of these pathways in pulmonary fibrosis, as well as the current status of drug research on the targets of LPAR1 and VEGFR2, are described. The mechanism by which these two pathways regulate vascular leakage and collagen deposition leading to the development of pulmonary fibrosis are analyzed, and the mutual promotion of the two pathways is discussed. Here we propose the development of drugs that simultaneously target LPAR1 and VEGFR2, and discuss the important considerations in targeting and safety.

The Role of Eosinophil-Derived Neurotoxin and Vascular Endothelial Growth Factor in the Pathogenesis of Eosinophilic Asthma

Asthma is a chronic complex pulmonary disease characterized by airway inflammation, remodeling, and hyperresponsiveness. Vascular endothelial growth factor (VEGF) and eosinophil-derived neurotoxin (EDN) are two significant mediators involved in the pathophysiology of asthma. In asthma, VEGF and EDN levels are elevated and correlate with disease severity and airway hyperresponsiveness. Diversity in VEGF polymorphisms results in the variability of responses to glucocorticosteroids and leukotriene antagonist treatment. Targeting VEGF and eosinophils is a promising therapeutic approach for asthma. We identified lichochalcone A, bevacizumab, azithromycin (AZT), vitamin D, diosmetin, epigallocatechin gallate, IGFBP-3, Neovastat (AE-941), endostatin, PEDF, and melatonin as putative add-on drugs in asthma with anti-VEGF properties. Further studies and clinical trials are needed to evaluate the efficacy of those drugs. AZT reduces the exacerbation rate and may be considered in adults with persistent symptomatic asthma. However, the long-term effects of AZT on community microbial resistance require further investigation. Vitamin D supplementation may enhance corticosteroid responsiveness. Herein, anti-eosinophil drugs are reviewed. Among them are, e.g., anti-IL-5 (mepolizumab, reslizumab, and benralizumab), anti-IL-13 (lebrikizumab and tralokinumab), anti-IL-4 and anti-IL-13 (dupilumab), and anti-IgE (omalizumab) drugs. EDN over peripheral blood eosinophil count is recommended to monitor the asthma control status and to assess the efficacy of anti-IL-5 therapy in asthma.

Updated perspective of EPAS1 and the role in pulmonary hypertension

Pulmonary hypertension (PH) is a group of syndromes characterized by irreversible vascular remodeling and persistent elevation of pulmonary vascular resistance and pressure, leading to ultimately right heart failure and even death. Current therapeutic strategies mainly focus on symptoms alleviation by stimulating pulmonary vessel dilation. Unfortunately, the mechanism and interventional management of vascular remodeling are still yet unrevealed. Hypoxia plays a central role in the pathogenesis of PH and numerous studies have shown the relationship between PH and hypoxia-inducible factors family. EPAS1, known as hypoxia-inducible factor-2 alpha (HIF-2α), functions as a transcription factor participating in various cellular pathways. However, the detailed mechanism of EPAS1 has not been fully and systematically described. This article exhibited a comprehensive summary of EPAS1 including the molecular structure, biological function and regulatory network in PH and other relevant cardiovascular diseases, and furthermore, provided theoretical reference for the potential novel target for future PH intervention.