Endothelial Cell Junctional Adhesion Molecules: Role and Regulation of Expression in Inflammation

Junctions at the crossroads: the impact of mechanical cues on endothelial cell-cell junction conformations and vascular permeability

Cells depend on precisely regulating barrier function within the vasculature to maintain physiological stability and facilitate essential substance transport. Endothelial cells achieve this through specialized adherens and tight junction protein complexes, which govern paracellular permeability across vascular beds. Adherens junctions, anchored by vascular endothelial (VE)-cadherin and associated catenins to the actin cytoskeleton, mediate homophilic adhesion crucial for barrier integrity. In contrast, tight junctions composed of occludin, claudin, and junctional adhesion molecule A interact with Zonula Occludens proteins, reinforcing intercellular connections essential for barrier selectivity. Endothelial cell-cell junctions exhibit dynamic conformations during development, maturation, and remodeling, regulated by local biochemical and mechanical cues. These structural adaptations play pivotal roles in disease contexts such as chronic inflammation, where junctional remodeling contributes to increased vascular permeability observed in conditions from cancer to cardiovascular diseases. Conversely, the brain microvasculature's specialized junctional arrangements pose challenges for therapeutic drug delivery due to their unique molecular compositions and tight organization. This commentary explores the molecular mechanisms underlying endothelial cell-cell junction conformations and their implications for vascular permeability. By highlighting recent advances in quantifying junctional changes and understanding mechanotransduction pathways, we elucidate how physical forces from cellular contacts and hemodynamic flow influence junctional dynamics.

27-Hydroxycholesterol Negatively Affects the Function of Bone Marrow Endothelial Cells in the Bone Marrow

Hematopoietic stem cells (HSCs) reside in specific microenvironments that facilitate their regulation through both internal mechanisms and external cues. Bone marrow endothelial cells (BMECs), which are found in one of these microenvironments, play a vital role in controlling the self-renewal and differentiation of HSCs during hematological stress. We previously showed that 27-hydroxycholesterol (27HC) administration of exogenous 27HC negatively affected the population of HSCs and progenitor cells by increasing the reactive oxygen species levels in the bone marrow. However, the effect of 27HC on BMECs is unclear. To determine the function of 27HC in BMECs, we employed magnetic-activated cell sorting to isolate CD31+ BMECs and CD31- cells. We demonstrated the effect of 27HC on CD31+ BMECs and HSCs. Treatment with exogenous 27HC led to a decrease in the number of BMECs and reduced the expression of adhesion molecules that are crucial for maintaining HSCs. Our results demonstrate that BMECs are sensitively affected by 27HC and are crucial for HSC survival.

Autophagy as a Guardian of Vascular Niche Homeostasis

The increasing burden of vascular dysfunction on healthcare systems worldwide results in higher morbidity and mortality rates across pathologies, including cardiovascular diseases. Vasculopathy is suggested to be caused by the dysregulation of vascular niches, a microenvironment of vascular structures comprising anatomical structures, extracellular matrix components, and various cell populations. These elements work together to ensure accurate control of the vascular network. In recent years, autophagy has been recognized as a crucial regulator of the vascular microenvironment responsible for maintaining basic cell functions such as proliferation, differentiation, replicative senescence, and apoptosis. Experimental studies indicate that autophagy activation can be enhanced or inhibited in various pathologies associated with vascular dysfunction, suggesting that autophagy plays both beneficial and detrimental roles. Here, we review and assess the principles of autophagy organization and regulation in non-tumor vascular niches. Our analysis focuses on significant figures in the vascular microenvironment, highlighting the role of autophagy and summarizing evidence that supports the systemic or multiorgan nature of the autophagy effects. Finally, we discuss the critical organizational and functional aspects of the vasculogenic niche, specifically in relation to autophagy. The resulting dysregulation of the vascular microenvironment contributes to the development of vascular dysfunction.

Arpin deficiency increases actomyosin contractility and vascular permeability

Arpin was discovered as an inhibitor of the Arp2/3 complex localized at the lamellipodial tip of fibroblasts, where it regulated migration steering. Recently, we showed that arpin stabilizes the epithelial barrier in an Arp2/3-dependent manner. However, the expression and functions of arpin in endothelial cells (EC) have not yet been described. Arpin mRNA and protein are expressed in EC and downregulated by pro-inflammatory cytokines. Arpin depletion in Human Umbilical Vein Endothelial Cells causes the formation of actomyosin stress fibers leading to increased permeability in an Arp2/3-independent manner. Instead, inhibitors of ROCK1 and ZIPK, kinases involved in the generation of stress fibers, normalize the loss-of-arpin effects on actin filaments and permeability. Arpin-deficient mice are viable but show a characteristic vascular phenotype in the lung including edema, microhemorrhage, and vascular congestion, increased F-actin levels, and vascular permeability. Our data show that, apart from being an Arp2/3 inhibitor, arpin is also a regulator of actomyosin contractility and endothelial barrier integrity.

Coupled single-cell and bulk RNA-seq analysis reveals the engulfment role of endothelial cells in atherosclerosis

The clearance of apoptotic cell debris, containing professional phagocytosis and non-professional phagocytosis, is essential for maintaining the homeostasis of healthy tissues. Here, we discovered that endothelial cells could engulf apoptotic cell debris in atherosclerotic plaque. Single-cell RNA sequencing (RNA-seq) has revealed a unique endothelial cell subpopulation in atherosclerosis, which was strongly associated with vascular injury-related pathways. Moreover, integrated analysis of three vascular injury-related RNA-seq datasets showed that the expression of scavenger receptor class B type 1 (SR-B1) was up-regulated and specifically enriched in the phagocytosis pathway under vascular injury circumstances. Single-cell RNA-seq and bulk RNA-seq indicate that SR-B1 was highly expressed in a unique endothelial cell subpopulation of mouse aorta and strongly associated with the reorganization of cellular adherent junctions and cytoskeleton which were necessary for phagocytosis. Furthermore, SR-B1 was strongly required for endothelial cells to engulf apoptotic cell debris in atherosclerotic plaque of both mouse and human aorta. Overall, this study demonstrated that apoptotic cell debris could be engulfed by endothelial cells through SR-B1 and associated with the reorganization of cellular adherent junctions and cytoskeleton.

Single-Cell RNA Sequencing Reveals a Unique Fibroblastic Subset and Immune Disorder in Lichen Sclerosus Urethral Stricture

Purpose

Lichen sclerosus urethral stricture disease (LS USD) is a refractory and progressive disease primarily affecting the anterior urethra in males. Various potential etiological factors, such as genetics, autoimmunity, infection, and exposure to infectious urine, have been suggested. However, the accurate etiology of LS in the male urethra remains unclear.

Patients and Methods

In this study, we conducted single-cell RNA sequencing to identify the transcriptional profiles of three patients with LS USD and three patients with non-LS USD. Immunofluorescence was used to confirm the single-cell sequence results.

Results

Our study revealed distinct subsets of vein endothelial cells (ECs), smooth muscle cells (SMCs), and fibroblasts (FBs) with high proportions in LS USD, contributing to the tissue microenvironment primarily involved in proinflammatory and immune responses. In particular, FBs displayed a unique subset, Fib7, which is exclusively present in LS USD, and exhibited high expression levels of SAA1 and SAA2. The accumulation of macrophages, along with the dysregulated ratios of M1/M2-like phenotype macrophages, may be engaged in the pathogenesis of LS USD. Through cell-cell communication analysis, we identified significant interactions involving CXCL8/ACKR1 and CCR7/CCL19 in LS USD. Remarkably, Fib7 exhibited exclusive communication with IL-1B macrophages through the SAA1/FPR2 receptor-ligand pair.

Conclusion

Our study provides a profound understanding of the tissue microenvironment in LS USD, which may be valuable for understanding the pathogenesis of LS USD.

Endothelial dysfunction of syphilis: Pathogenesis

Treponema pallidum is the causative factor of syphilis, a sexually transmitted disease (STD) characterized by perivascular infiltration of inflammatory cells, vascular leakage, swelling and proliferation of endothelial cells (ECs). The endothelium lining blood and lymphatic vessels is a key barrier separating body fluids from host tissues and is a major target of T. pallidum. In this review, we focus on how T. pallidum establish intimate interactions with ECs, triggering endothelial dysfunction such as endothelial inflammation, abnormal repairment and damage of ECs. In addition, we summarize that migration and invasion of T. pallidum across vascular ECs may occur through two pathways. These two mechanisms of transendothelial migration are paracellular and cholesterol-dependent, respectively. Herein, clarifying the relationship between T. pallidum and endothelial dysfunction is of great significance to provide novel strategies for diagnosis and prevention of syphilis, and has a great potential prospect of clinical application.

Cancer Metastasis-on-a-Chip for Modeling Metastatic Cascade and Drug Screening

Microfluidic chips are valuable tools for studying intricate cellular and cell-microenvironment interactions. Traditional in vitro cancer models lack accuracy in mimicking the complexities of in vivo tumor microenvironment. However, cancer-metastasis-on-a-chip (CMoC) models combine the advantages of 3D cultures and microfluidic technology, serving as powerful platforms for exploring cancer mechanisms and facilitating drug screening. These chips are able to compartmentalize the metastatic cascade, deepening the understanding of its underlying mechanisms. This article provides an overview of current CMoC models, focusing on distinctive models that simulate invasion, intravasation, circulation, extravasation, and colonization, and their applications in drug screening. Furthermore, challenges faced by CMoC and microfluidic technologies are discussed, while exploring promising future directions in cancer research. The ongoing development and integration of these models into cancer studies are expected to drive transformative advancements in the field.

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.

Echinacoside activates Nrf2/PPARγ signaling pathway to modulate mitochondrial fusion-fission balance to ameliorate ox-LDL-induced dysfunction of coronary artery endothelial cells

As a cardiovascular disease, coronary heart disease (CHD) is characterized by poor prognosis and increasing morbidity and mortality rates. Echinacoside (ECH) can protect against multiple cardiovascular diseases due to its antioxidant and anti-inflammatory properties. However, the role of ECH in CHD remains unclear. In ECH-treated human coronary artery endothelial cells (HCAECs), cell viability, NO production, endothelial nitric oxide synthase (eNOS) expression, and angiogenesis ability were detected using cell counting kit-8 (CCK-8) assay, diaminofluorescein-FM diacetate (DAF-FM DA) staining, western blot, and tube formation assay, respectively. The activities of oxidative stress markers were detected using dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay and corresponding assay kits. Cell apoptosis was detected utilizing flow cytometry and caspase3 assay. Western blot was used to detect the expressions of Nrf2/PPARγ signaling pathway- and mitochondrial dynamics-related proteins. Mitochondrial membrane potential and mitochondrial fusion and fission were detected using JC-1 staining and immunofluorescence (IF) assay. In this study, ECH was found to revive the viability, ameliorate the endothelial dysfunction, suppress oxidative stress, and inhibit the apoptosis in ox-LDL-induced HCAECs via activating Nrf2/PPARγ signaling pathway, which were all abolished following the treatment of Nrf2 inhibitor ML385. It was also identified that ECH regulated mitochondrial fusion-fission balance in ox-LDL-induced HCAECs through the activation of Nrf2/PPARγ signaling pathway. In summary, ECH activated Nrf2/PPARγ signaling pathway to regulate mitochondrial fusion-fission balance, thereby improving ox-LDL-induced dysfunction of HCAECs.

Metrnl inhibits choroidal neovascularization by attenuating the choroidal inflammation via inactivating the UCHL-1/NF-κB signaling pathway

Objective

Choroidal neovascularization (CNV) represents the predominant form of advanced wet Age-related Macular Degeneration (wAMD). Macrophages play a pivotal role in the pathological progression of CNV. Meteorin-like (Metrnl), a novel cytokine known for its anti-inflammatory properties in macrophages, is the focus of our investigation into its mechanism of action and its potential to impede CNV progression.

Methods

Cell viability was evaluated through CCK-8 and EdU assays following Metrnl treatment. Expression levels of inflammatory cytokines and proteins were assessed using quantitative reverse-transcription polymerase chain reaction(qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot techniques. Protein-protein interactions were identified through protein mass spectrometry and co-immunoprecipitation (Co-IP). Additionally, in vivo and in vitro neovascularization models were employed to evaluate angiogenesis.

Results

Our results revealed downregulated Metrnl levels in the choroid-sclera complex of CNV mice, the aqueous humor of wAMD patients, and activated macrophages. Metrnl overexpression demonstrated a reduction in pro-inflammatory cytokine production, influenced endothelial cell function, and suppressed angiogenesis in choroid explants and CNV models. Through protein mass spectrometry and Co-IP, we confirmed Metrnl binds to UCHL-1 to modulate the NF-κB signaling pathway. This interaction inhibited the transcription and expression of pro-inflammatory cytokines, ultimately suppressing angiogenesis.

Conclusion

In summary, our findings indicate that Metrnl down-regulates macrophage pro-inflammatory cytokine secretion via the UCHL-1/NF-κB signaling pathway. This mechanism alleviates the inflammatory microenvironment and effectively inhibits choroidal neovascularization.

The Role of NRF2 in Cerebrovascular Protection: Implications for Vascular Cognitive Impairment and Dementia (VCID)

Vascular cognitive impairment and dementia (VCID) represents a broad spectrum of cognitive decline secondary to cerebral vascular aging and injury. It is the second most common type of dementia, and the prevalence continues to increase. Nuclear factor erythroid 2-related factor 2 (NRF2) is enriched in the cerebral vasculature and has diverse roles in metabolic balance, mitochondrial stabilization, redox balance, and anti-inflammation. In this review, we first briefly introduce cerebrovascular aging in VCID and the NRF2 pathway. We then extensively discuss the effects of NRF2 activation in cerebrovascular components such as endothelial cells, vascular smooth muscle cells, pericytes, and perivascular macrophages. Finally, we summarize the clinical potential of NRF2 activators in VCID.

Investigating the therapeutic effects and mechanisms of Carthamus tinctorius L.-derived nanovesicles in atherosclerosis treatment

BACKGROUND

Carthamus tinctorius L., a traditional herbal medicine used for atherosclerosis (AS), lacks a clear understanding of its therapeutic mechanisms. This study aimed to investigate the therapeutic effects and mechanisms of Carthamus tinctorius L.-derived nanovesicles (CDNVs) in AS treatment.

METHODS

CDNVs were isolated and characterized using improved isolation methods. Transmission electron microscopy, nanoparticle tracking analysis, and protein analysis confirmed their morphology, size, and protein composition. Small RNA sequencing was performed to identify the miRNA profile of CDNVs, and bioinformatics analysis was used to determine their potential biological roles. In vivo biodistribution and toxicity studies were conducted in mice to assess the stability and safety of orally administered CDNVs. The anti-atherosclerotic effects of CDNVs were evaluated in ApoE-/- mice through plaque burden analysis. The protective effects of CDNVs on ox-LDL-treated endothelial cells were assessed through proliferation, apoptosis, reactive oxygen species activation, and monocyte adhesion assays. miRNA and mRNA sequencing of CDNV-treated endothelial cells were performed to explore their regulatory effects and potential target genes.

RESULTS

CDNVs were successfully isolated and purified from Carthamus tinctorius L. tissue lysates. They exhibited a saucer-shaped or cup-shaped morphology, with an average particle size of 142.6 ± 0.7 nm, and expressed EV markers CD63 and TSG101. CDNVs contained proteins, small RNAs, and metabolites, including the therapeutic compound HSYA. Small RNA sequencing identified 95 miRNAs, with 10 common miRNAs accounting for 72.63% of the total miRNAs. These miRNAs targeted genes involved in cell adhesion, apoptosis, and cell proliferation, suggesting their relevance in cardiovascular disease. Orally administered CDNVs were stable in the gastrointestinal tract, absorbed into the bloodstream, and accumulated in the liver, lungs, heart, and aorta. They significantly reduced the burden of atherosclerotic plaques in ApoE-/- mice and exhibited superior effects compared to HSYA. In vitro studies demonstrated that CDNVs were taken up by HUVECs, promoted proliferation, attenuated ox-LDL-induced apoptosis and ROS activation, and reduced monocyte adhesion. CDNV treatment resulted in significant changes in miRNA and mRNA expression profiles of HUVECs, with enrichment in inflammation-related genes. CXCL12 was identified as a potential direct target of miR166a-3p.

CONCLUSION

CDNVs isolated from Carthamus tinctorius L. tissue lysates represent a promising oral therapeutic option for cardiovascular diseases. The delivery of miRNAs by CDNVs regulates inflammation-related genes, including CXCL12, in HUVECs, suggesting their potential role in modulating endothelial inflammation. These findings provide valuable insights into the therapeutic potential of CDNVs and their miRNAs in cardiovascular disease.

Amyloid β interferes with wound healing of brain microvascular endothelial cells by disorganizing the actin cytoskeleton

Cerebral amyloid angiopathy (CAA) is a disease in which amyloid β (Aβ) is deposited in the cerebral blood vessels, reducing compliance, tearing and weakening of vessel walls, leading to cerebral hemorrhage. The mechanisms by which Aβ leads to focal wall fragmentation and intimal damage are not well understood. We analyzed the motility of human brain microvascular endothelial cells (hBMECs) in real-time using a wound-healing assay. We observed the suppression of cell migration by visualizing Aβ aggregation using quantum dot (QD) nanoprobes. In addition, using QD nanoprobes and a SiR-actin probe, we simultaneously observed Aβ aggregation and F-actin organization in real-time for the first time. Aβ began to aggregate at the edge of endothelial cells, reducing cell motility. In addition, Aβ aggregation disorganized the actin cytoskeleton and induced abnormal actin aggregation. Aβ aggregated actively in the anterior group, where cell motility was active. Our findings may be a first step toward explaining the mechanism by which Aβ causes vascular wall fragility, bleeding, and rebleeding in CAA.

Blood endothelium transition and phenotypic plasticity: A key regulator of integrity/permeability in response to ischemia

In the human body, the 1013 blood endothelial cells (ECs) which cover a surface of 500-700 m2 (Mai et al., 2013) are key players of tissue homeostasis, remodeling and regeneration. Blood vessel ECs play a major role in the regulation of metabolic and gaz exchanges, cell trafficking, blood coagulation, vascular tone, blood flow and fluid extravasation (also referred to as blood vascular permeability). ECs are heterogeneous in various capillary beds and have the exquisite capacity to cope with environmental changes by regulating their gene expression. Ischemia has major detrimental effects on the endothelium and ischemia-induced regulation of vascular integrity is of paramount importance for human health, as small amounts of fluid accumulation in the interstitium may be responsible for major effects on organ functions and patients outcome. In this review, we will here focus on the stimuli and the molecular mechanisms that control blood endothelium maintenance and phenotypic plasticity/transition involved in controlling blood capillary leakage that might open new avenues for therapeutic applications.

How the immune response to the structural proteins of SARS-CoV-2 affects the retinal vascular endothelial cells: an immune thrombotic and/or endotheliopathy process with in silico modeling

Thrombotic events associated with SARS-CoV-2 at the vascular endothelium still remains unclear. The aim of the current study is to determine the relationship between cellular proteins on the (ocular) vascular endothelial surface and the immune thrombotic and/or endotheliopathy process elicited by SARS-CoV-2 using an in-silico modeling. The structural S (spike glycoprotein), N (nucleocapsid protein), M (membrane protein), and E (envelope protein) proteins, an accessory protein (ORF1ab) of SARS-CoV-2 and 158 cellular proteins associated with retinal vascular endothelial cell surface or structure were included in this study for comparison of three-dimensional (3D) structure and sequence. Sixty-nine of the retinal proteins were obtained from the Uniprot database. Remaining proteins not included in the database were included in the study after they were converted into 3D structures using the RaptorX web tool. Sequence and three-dimensional structure of SARS-COV-2 S, N, M, E, ORF1ab proteins and retinal vascular endothelial proteins were compared with mTM-align server. Proteins with significant similarity (score above 0.5) were validated with the TM-align web server. Immune and thrombosis-related protein-receptor interactions of similar proteins was checked with CABS-dock. We detected a high level of structural similarity between E protein and ACE, ACE2, LAT1, and TM9SF4 endothelial proteins. In addition, PECAM-1 was found to be structurally similar to ORF1ab and S protein. When we evaluated the likelihood/potential to stimulate an immune responses/a cytokine release, TLR-2 and TLR-3, which are highly susceptible to SARS-CoV2, showed a potential receptor-protein interaction with retinal vascular endothelial proteins. Our study demonstrates that SARS-CoV-2 proteins may have structural similarities with vascular endothelial proteins, and therefore, as immunological target sites, the counterpart proteins on the endothelial surface of many organs may also be secondarily affected by any immune response against SARS-CoV-2 structural proteins.

Oleanolic acid rescues critical features of umbilical vein endothelial cells permanently affected by hyperglycemia

Skin wound healing is a physiological process that involves several cell types. Among them, endothelial cells are required for inflammation resolution and neo-angiogenesis, both necessary for tissue restoration after injury. Primary human umbilical vein endothelial cells (C-HUVECs) are derived from the umbilical cord. When women develop gestational diabetes, chronic exposure to hyperglycemia induces epigenetic modifications in these cells (GD-HUVECs), leading to a permanent pro-inflammatory phenotype and impaired angiogenesis in contrast to control cells. Oleanolic acid (OA) is a bioactive triterpenoid known for its epithelial cell migration promotion stimulation and higher tensile strength of wounds. However, the potentially anti-inflammatory and pro-angiogenic properties of OA are still under investigation. We tested OA on C- and GD-HUVECs under inflammatory conditions induced by low levels of the inflammatory cytokine TNF-α. Reduced expression of adhesion molecules VCAM1, ICAM1, and SELE was obtained in OA-pre-treated C- and GD-HUVECs. Additionally, protein VCAM1 levels were also decreased by OA. Coherently, monocyte adhesion assays showed that a lower number of monocytes adhered to GD-HUVEC endothelium under OA pre-treatment when compared to untreated ones. It is noteworthy that OA improved angiogenesis parameters in both phenotypes, being especially remarkable in the case of GD-HUVECs, since OA strongly rescued their poor tube formation behavior. Moreover, endothelial cell migration was improved in C- and GD-HUVECs in scratch assays, an effect that was further confirmed by focal adhesion (FA) remodeling, revealed by paxillin staining on immunocytochemistry assays. Altogether, these results suggest that OA could be an emergent wound healing agent due to its capacity to rescue endothelial malfunction caused by hyperglycemia.

Race and sex differences in ROS production and SOD activity in HUVECs

Black individuals and men are predisposed to an earlier onset and higher prevalence of hypertension, compared with White individuals and women, respectively. Therefore, the influence of race and sex on reactive oxygen species (ROS) production and superoxide dismutase (SOD) activity following induced inflammation was evaluated in female and male human umbilical vein endothelial cells (HUVECs) from Black and White individuals. It was hypothesized that HUVECs from Black individuals and male HUVECs would exhibit greater ROS production and impaired SOD activity. Inflammation was induced in HUVEC cell lines (n = 4/group) using tumor necrosis factor-alpha (TNF-α, 50ng/ml). There were no between group differences in ROS production or SOD activity in HUVECs from Black and White individuals, and HUVECs from Black individuals exhibited similar SOD activity at 24hr compared with 4hr of TNF-α treatment (p>0.05). However, HUVECs from White individuals exhibited significantly greater SOD Activity (p<0.05) at 24hr as compared to 4hr in the control condition but not with TNF-α treatment (p>0.05). Female HUVECs exhibited significantly lower ROS production than male HUVECs in the control condition and following TNF-α induced inflammation (p<0.05). Only female HUVECs exhibited significant increases in SOD activity with increased exposure time to TNF-α induced inflammation (p<0.05). HUVECs from White individuals alone exhibit blunted SOD activity when comparing control and TNF-α conditions. Further, compared to female HUVECs, male HUVECs exhibit a pro-inflammatory state.

Inflammatory responsive neutrophil-like membrane-based drug delivery system for post-surgical glioblastoma therapy

Surgical resection of glioblastoma (GBM) causes brain inflammation that activates and recruits neutrophils (NEs) to residual GBM tissues. NE-based drug delivery using inflammatory chemotaxis is promising for the post-surgical treatment of residual GBM, but its clinical application is limited by the short life span of NEs and lack of in vitro propagation methods. HL60 cells are a type of infinitely multiplying tumor cells that can be induced to differentiate into NE-like cells. We developed a novel NE-like membrane system (NM-PD) by coating NE-like membranes on the surface of poly (lactide-co-glycolide)-poly(ethylene glycol) (PLGA-PEG)-based doxorubicin (DOX)-loaded core (PLGA-PEG-DOX, PD) for post-surgical residual GBM treatment. Cell adhesion proteins were detected on NE-like membranes and endowed NM-PDs with inflammatory chemotaxis similar to mature NEs. The resulting NM-PD shows excellent inflamed in vitro blood-brain barrier (BBB) permeability and anti-proliferative effects on GBM cells. In our intracranial GBM resection model, NM-PD exhibited superior inflammatory chemotaxis and targeted residual GBM cells, thus remarkably improving antitumor capability and prolonging the survival time of the mice. These data suggest that NM-PD, which has sufficient sources and is easy to prepare, can efficiently suppress post-surgical residual GBM and holds potential for clinical transformation in GBM post-surgical adjuvant therapy.

Endothelial cell plasticity in kidney fibrosis and disease

Renal endothelial cells demonstrate an impressive remodeling potential during angiogenic sprouting, vessel repair or while transitioning into mesenchymal cells. These different processes may play important roles in both renal disease progression or regeneration while underlying signaling pathways of different endothelial cell plasticity routes partly overlap. Angiogenesis contributes to wound healing after kidney injury and pharmaceutical modulation of angiogenesis may home a great therapeutic potential. Yet, it is not clear whether any differentiated endothelial cell can proliferate or whether regenerative processes are largely controlled by resident or circulating endothelial progenitor cells. In the glomerular compartment for example, a distinct endothelial progenitor cell population may remodel the glomerular endothelium after injury. Endothelial-to-mesenchymal transition (EndoMT) in the kidney is vastly documented and often associated with endothelial dysfunction, fibrosis, and kidney disease progression. Especially the role of EndoMT in renal fibrosis is controversial. Studies on EndoMT in vivo determined possible conclusions on the pathophysiological role of EndoMT in the kidney, but whether endothelial cells really contribute to kidney fibrosis and if not what other cellular and functional outcomes derive from EndoMT in kidney disease is unclear. Sequencing data, however, suggest no participation of endothelial cells in extracellular matrix deposition. Thus, more in-depth classification of cellular markers and the fate of EndoMT cells in the kidney is needed. In this review, we describe different signaling pathways of endothelial plasticity, outline methodological approaches and evidence for functional and structural implications of angiogenesis and EndoMT in the kidney, and eventually discuss controversial aspects in the literature.

Exploring the crosstalk between endothelial cells, immune cells, and immune checkpoints in the tumor microenvironment: new insights and therapeutic implications

The tumor microenvironment (TME) is a highly intricate milieu, comprising a multitude of components, including immune cells and stromal cells, that exert a profound influence on tumor initiation and progression. Within the TME, angiogenesis is predominantly orchestrated by endothelial cells (ECs), which foster the proliferation and metastasis of malignant cells. The interplay between tumor and immune cells with ECs is complex and can either bolster or hinder the immune system. Thus, a comprehensive understanding of the intricate crosstalk between ECs and immune cells is essential to advance the development of immunotherapeutic interventions. Despite recent progress, the underlying molecular mechanisms that govern the interplay between ECs and immune cells remain elusive. Nevertheless, the immunomodulatory function of ECs has emerged as a pivotal determinant of the immune response. In light of this, the study of the relationship between ECs and immune checkpoints has garnered considerable attention in the field of immunotherapy. By targeting specific molecular pathways and signaling molecules associated with ECs in the TME, novel immunotherapeutic strategies may be devised to enhance the efficacy of current treatments. In this vein, we sought to elucidate the relationship between ECs, immune cells, and immune checkpoints in the TME, with the ultimate goal of identifying novel therapeutic targets and charting new avenues for immunotherapy.

Transcriptome Profiling Based at Different Time Points after Hatching Deepened Our Understanding on Larval Growth and Development of Amphioctopus fangsiao

As the quality of life improves, there is an increasing demand for nutrition-rich marine organisms like fish, shellfish, and cephalopods. To address this, artificial cultivation of these organisms is being explored along with ongoing research on their growth and development. A case in point is Amphioctopus fangsiao, a highly valued cephalopod known for its tasty meat, nutrient richness, and rapid growth rate. Despite its significance, there is a dearth of studies on the A. fangsiao growth mechanism, particularly of its larvae. In this study, we collected A. fangsiao larvae at 0, 4, 12, and 24 h post-hatching and conducted transcriptome profiling. Our analysis identified 4467, 5099, and 4181 differentially expressed genes (DEGs) at respective intervals, compared to the 0 h sample. We further analyzed the expression trends of these DEGs, noting a predominant trend of continuous upregulation. Functional exploration of this trend entailed GO and KEGG functional enrichment along with protein-protein interaction network analyses. We identified GLDC, DUSP14, DPF2, GNAI1, and ZNF271 as core genes, based on their high upregulation rate, implicated in larval growth and development. Similarly, CLTC, MEF2A, PPP1CB, PPP1R12A, and TJP1, marked by high protein interaction numbers, were identified as hub genes and the gene expression levels identified via RNA-seq analysis were validated through qRT-PCR. By analyzing the functions of key and core genes, we found that the ability of A. fangsiao larvae to metabolize carbohydrates, lipids, and other energy substances during early growth may significantly improve with the growth of the larvae. At the same time, muscle related cells in A. fangsiao larvae may develop rapidly, promoting the growth and development of larvae. Our findings provide preliminary insights into the growth and developmental mechanism of A. fangsiao, setting the stage for more comprehensive understanding and broader research into cephalopod growth and development mechanisms.

Monocyte-endothelial cell interactions in vascular and tissue remodeling

Monocytes are circulating leukocytes of innate immunity derived from the bone marrow that interact with endothelial cells under physiological or pathophysiological conditions to orchestrate inflammation, angiogenesis, or tissue remodeling. Monocytes are attracted by chemokines and specific receptors to precise areas in vessels or tissues and transdifferentiate into macrophages with tissue damage or infection. Adherent monocytes and infiltrated monocyte-derived macrophages locally release a myriad of cytokines, vasoactive agents, matrix metalloproteinases, and growth factors to induce vascular and tissue remodeling or for propagation of inflammatory responses. Infiltrated macrophages cooperate with tissue-resident macrophages during all the phases of tissue injury, repair, and regeneration. Substances released by infiltrated and resident macrophages serve not only to coordinate vessel and tissue growth but cellular interactions as well by attracting more circulating monocytes (e.g. MCP-1) and stimulating nearby endothelial cells (e.g. TNF-α) to expose monocyte adhesion molecules. Prolonged tissue accumulation and activation of infiltrated monocytes may result in alterations in extracellular matrix turnover, tissue functions, and vascular leakage. In this review, we highlight the link between interactions of infiltrating monocytes and endothelial cells to regulate vascular and tissue remodeling with a special focus on how these interactions contribute to pathophysiological conditions such as cardiovascular and chronic liver diseases.

Common and distinct functions of mouse Dot1l in the regulation of endothelial transcriptome

Epigenetic mechanisms are mandatory for endothelial called lymphangioblasts during cardiovascular development. Dot1l-mediated gene transcription in mice is essential for the development and function of lymphatic ECs (LECs). The role of Dot1l in the development and function of blood ECs blood endothelial cells is unclear. RNA-seq datasets from Dot1l-depleted or -overexpressing BECs and LECs were used to comprehensively analyze regulatory networks of gene transcription and pathways. Dot1l depletion in BECs changed the expression of genes involved in cell-to-cell adhesion and immunity-related biological processes. Dot1l overexpression modified the expression of genes involved in different types of cell-to-cell adhesion and angiogenesis-related biological processes. Genes involved in specific tissue development-related biological pathways were altered in Dot1l-depleted BECs and LECs. Dot1l overexpression altered ion transportation-related genes in BECs and immune response regulation-related genes in LECs. Importantly, Dot1l overexpression in BECs led to the expression of genes related to the angiogenesis and increased expression of MAPK signaling pathways related was found in both Dot1l-overexpressing BECs and LECs. Therefore, our integrated analyses of transcriptomics in Dot1l-depleted and Dot1l-overexpressed ECs demonstrate the unique transcriptomic program of ECs and the differential functions of Dot1l in the regulation of gene transcription in BECs and LECs.

The Role of Punicalagin and Its Metabolites in Atherosclerosis and Risk Factors Associated with the Disease

Atherosclerotic cardiovascular disease (ACVD) is the leading cause of death worldwide. Although current therapies, such as statins, have led to a marked reduction in morbidity and mortality from ACVD, they are associated with considerable residual risk for the disease together with various adverse side effects. Natural compounds are generally well-tolerated; a major recent goal has been to harness their full potential in the prevention and treatment of ACVD, either alone or together with existing pharmacotherapies. Punicalagin (PC) is the main polyphenol present in pomegranates and pomegranate juice and demonstrates many beneficial actions, including anti-inflammatory, antioxidant, and anti-atherogenic properties. The objective of this review is to inform on our current understanding of the pathogenesis of ACVD and the potential mechanisms underlying the beneficial actions of PC and its metabolites in the disease, including the attenuation of dyslipidemia, oxidative stress, endothelial cell dysfunction, foam cell formation, and inflammation mediated by cytokines and immune cells together with the regulation of proliferation and migration of vascular smooth muscle cells. Some of the anti-inflammatory and antioxidant properties of PC and its metabolites are due to their strong radical-scavenging activities. PC and its metabolites also inhibit the risk factors of atherosclerosis, including hyperlipidemia, diabetes mellitus, inflammation, hypertension, obesity, and non-alcoholic fatty liver disease. Despite the promising findings that have emerged from numerous in vitro, in vivo, and clinical studies, deeper mechanistic insights and large clinical trials are required to harness the full potential of PC and its metabolites in the prevention and treatment of ACVD.

Association between Behavioural Risks and Alzheimer's Disease: Elucidated with an Integrated Analysis of Gene Expression Patterns and Molecular Mechanisms

Alzheimer's disease (AD) remains a global health challenge. Previous studies have reported linkages between AD and multiple behavioural risk exposures, however, the underlying biological mechanisms and crucial genes of gene expression patterns driven by behavioural risks on the onset or progression of AD remains ambiguous. In this study, we performed an integrated analysis on the influence of behavioural risks including smoking, excessive alcohol consumption, physical inactivity, and non-healthy dietary pattern on AD with a comprehensive strategy. Our results demonstrated that multiple behavioural risk exposures could independently or collectively influence diverse hierarchical levels of gene expression patterns through multiple biological mechanisms such as Wnt, mitogen-activated protein kinase (MAPK), AMP-activated protein kinase (AMPK), nuclear factor (NF)-κB, phosphatidylinositol 3-kinase (PI3K)-Akt, and insulin (INS) signalling pathways-mediated pathological processes, thereby prodromally or intermediately impacting AD. Our study provided insights into understanding the association of behavioural risk exposures with AD and informative support for further studies.

Hyperforin regulates renal fibrosis via targeting the PI3K-AKT/ICAM1 axis

OBJECTIVE

To explore the role and mechanism of hyperforin (one of the active components of Sophora flavescens) in renal fibrosis.

METHODS

The active compounds and target proteins of Sophora flavescens were first screened through TCMSP (https://tcmsp-e.com/). The renal fibrosis-related genes were analyzed through GeneCards (https://www.genecards.org/). The differentially expressed genes (DEGs) in renal fibrosis in GEO dataset GSE156181 were obtained. Metascape was applied for target protein enrichment analysis. TGF-β1-stimulated renal tubular epithelial cells were used for renal fibrosis cell model establishment. The unilateral ureteral obstruction (UUO) mouse model was used for the renal fibrosis in vivo model. Cell viability was detected using an MTT assay. Immunofluorescence staining was employed to detect cell morphology changes and the expression of α-SMA and collagen I. Hematoxylin and eosin (H&E) and Masson staining were employed to determine the renal morphologic change. qRT-PCR or Western blotting was applied to determine the expression levels of the target proteins.

RESULTS

After intersecting the analysis results of TCMSP, GeneCards, and dataset GSE156181, hyperforin targeting ICAM1 was identified. Metascape pathway enrichment analysis results revealed that the effective compounds of Sophora flavescens were tightly associated with extracellular matrix (ECM) remodeling and inflammatory response. MTT assay demonstrated that hyperforin had no toxic effect on cells. Immunofluorescence staining results evidenced that hyperforin could partially restore TGF-β1-induced epithelial-mesenchymal transition (EMT), the PI3K/AKT pathway activation, and ICAM1 upregulation, and these effects of hyperforin could be reversed by ICAM1 overexpression. While the PI3K/AKT pathway activator IGF-1 effectively reversed the EMT inhibition effect of hyperforin on renal tubular epithelial cells. Moreover, the UUO mouse model further confirmed that hyperforin reduced renal fibrosis.

CONCLUSION

Hyperforin inhibited renal fibrosis via the PI3K/AKT/ICAM1 axis.

PIEZO1 and PECAM1 interact at cell-cell junctions and partner in endothelial force sensing

Two prominent concepts for the sensing of shear stress by endothelium are the PIEZO1 channel as a mediator of mechanically activated calcium ion entry and the PECAM1 cell adhesion molecule as the apex of a triad with CDH5 and VGFR2. Here, we investigated if there is a relationship. By inserting a non-disruptive tag in native PIEZO1 of mice, we reveal in situ overlap of PIEZO1 with PECAM1. Through reconstitution and high resolution microscopy studies we show that PECAM1 interacts with PIEZO1 and directs it to cell-cell junctions. PECAM1 extracellular N-terminus is critical in this, but a C-terminal intracellular domain linked to shear stress also contributes. CDH5 similarly drives PIEZO1 to junctions but unlike PECAM1 its interaction with PIEZO1 is dynamic, increasing with shear stress. PIEZO1 does not interact with VGFR2. PIEZO1 is required in Ca2+-dependent formation of adherens junctions and associated cytoskeleton, consistent with it conferring force-dependent Ca2+ entry for junctional remodelling. The data suggest a pool of PIEZO1 at cell junctions, the coming together of PIEZO1 and PECAM1 mechanisms and intimate cooperation of PIEZO1 and adhesion molecules in tailoring junctional structure to mechanical requirement.

Role of CD34 in inflammatory bowel disease

Inflammatory bowel disease (IBD) is caused by a variety of pathogenic factors, including chronic recurrent inflammation of the ileum, rectum, and colon. Immune cells and adhesion molecules play an important role in the course of the disease, which is actually an autoimmune disease. During IBD, CD34 is involved in mediating the migration of a variety of immune cells (neutrophils, eosinophils, and mast cells) to the inflammatory site, and its interaction with various adhesion molecules is involved in the occurrence and development of IBD. Although the function of CD34 as a partial cell marker is well known, little is known on its role in IBD. Therefore, this article describes the structure and biological function of CD34, as well as on its potential mechanism in the development of IBD.

Snake venom, a potential treatment for melanoma. A systematic review

Despite advances in treating patients with melanoma, there are still many treatment challenges to overcome. Studies with snake venom-derived proteins/peptides describe their binding potential, and inhibition of some proliferative mechanisms in melanoma. The combined use of these compounds with current therapies could be the strategic gap that will help us discover more effective treatments for melanoma. The present study aimed to carry out a systematic review identifying snake venom proteins and peptides described in the literature with antitumor, antimetastatic, or antiangiogenic effects on melanoma and determine the mechanisms of action that lead to these anti-tumor effects. Snake venoms contain proteins and peptides which are antiaggregant, antimetastatic, and antiangiogenic. The in vivo results are encouraging, considering the reduction of metastases and tumor size after treatment. In addition to these results, it was reported that these venom compounds could act in combination with chemotherapeutics (Acurhagin-C; Macrovipecetin), sensitizing and preparing tumor cells for treatment. There is a consensus that snake venom is a promising strategy for the improvement of antimelanoma therapies, but it has been little explored in the current context, combined with inhibitors, immunotherapy or tumor microenvironment, for example. We suggest Lebein as a candidate for combination therapy with BRAF inhibitors.

Impact of spatial and temporal stability of flow vortices on vascular endothelial cells

PURPOSE

Intracranial aneurysms (IAs) are pathological dilations of cerebrovascular vessels due to degeneration of the mechanical strength of the arterial wall, precluded by altered cellular functionality. The presence of swirling hemodynamic flow (vortices) is known to alter vascular endothelial cell (EC) morphology and protein expression indicative of IAs. Unfortunately, less is known if vortices with varied spatial and temporal stability lead to differing levels of EC change. The aim of this work is to investigate vortices of varying spatial and temporal stability impact on ECs.

METHODS

Vortex and EC interplay was investigated by a novel combination of parallel plate flow chamber (PPFC) design and computational analysis. ECs were exposed to laminar (7.5 dynes/[Formula: see text] wall shear stress) or low (<1 dynes/[Formula: see text]) stress vortical flow using PPFCs. Immunofluorescent imaging analyzed EC morphology, while ELISA tests quantified VE-cadherin (cell-cell adhesion), VCAM-1 (macrophage-EC adhesion), and cleaved caspase-3 (apoptotic signal) expression. PPFC flow was simulated, and vortex stability was calculated via the temporally averaged degree of (volume) overlap (TA-DVO) of vortices within a given area.

RESULTS

EC morphological changes were independent of vortex stability. Increased stability promoted VE-cadherin degradation (correlation coefficient r = [Formula: see text]0.84) and 5-fold increased cleaved caspase-3 post 24 h in stable (TA-DVO 0.736 ± 0.05) vs unstable (TA-DVO 0.606 [Formula: see text]0.2) vortices. ECs in stable vortices displayed a 4.5-fold VCAM-1 increase than unstable counterparts after 12 h.

CONCLUSION

This work demonstrates highly stable disturbed flow imparts increased inflammatory signaling, degraded cell-cell adhesion, and increased cellular apoptosis than unstable vortices. Such knowledge offers novel insight toward understanding IA development and rupture.

Differential Expression of LOXL1-AS1 in Coronary Heart Disease and its Regulatory Mechanism in ox-LDL-Induced Human Coronary Artery Endothelial Cell Pyroptosis

OBJECTIVE

Coronary heart disease (CHD) is a notable contributor to the burden of human health. Dysregulated long non-coding RNAs (lncRNAs) are implicated in the pathogenesis of CHD. This study investigated the expression pattern of lncRNA LOXL1-AS1 in CHD and its regulatory mechanism in oxidized low-density lipoprotein (ox-LDL)-induced human coronary artery endothelial cell (HCAEC) pyroptosis.

METHODS

Serum was collected from 62 CHD patients and 62 healthy volunteers for the detection of LOXL1-AS1 expression. The value of LOXL1-AS1 in CHD diagnosis and major cardiovascular adverse event (MACE) prediction was analyzed using the ROC curve. LOXL1-AS1, miR-16-5p, and SNX16 expressions in ox-LDL-treated HCAECs were determined using RT-qPCR. NLPR3, cleaved-caspase-1, and GSDMD-N protein levels were measured using Western blot. IL-1β and IL-18 concentrations were measured using ELISA. The binding relationships between LOXL1-AS1 and miR-16-5p and miR-16-5p and SNX16 were verified. Functional rescue experiment was performed to verify the role of miR-16-5p in HCAEC pyroptosis.

RESULTS

LOXL1-AS1 was highly expressed in CHD patients. LOXL1-AS1 had diagnostic value for CHD and predictive value for MACE occurrence. ox-LDL-treated HCAECs showed reduced viability, increased IL-1β and IL-18 concentrations, and elevated NLPR3, cleaved-caspase-1, and GSDMD-N levels. LOXL1-AS1 silencing promoted cell viability and reduced pyroptosis. LOXL1-AS1 bound to miR-16-5p and miR-16-5p targeted SNX16. Inhibition of miR-16-5p reversed the inhibitory effect of LOXL1-AS1 silencing on HCAEC pyroptosis.

CONCLUSION

LOXL1-AS1 was elevated in CHD patients with a good diagnostic value for CHD and predictive value for MACE. LOXL1-AS1 downregulated miR-16-5p expression by binding to miR-16-5p to enhance ox-LDL-induced HCAEC pyroptosis, which may be associated with upregulation of SNX16 transcription.

The Molecular Basis of the Anti-Inflammatory Property of Astragaloside IV for the Treatment of Diabetes and Its Complications

Astragali Radix is a significant traditional Chinese medication, and has a long history of clinical application in the treatment of diabetes mellitus (DM) and its complications. AS-IV is an active saponin isolated from it. Modern pharmacological study shows that AS-IV has anti-inflammatory, anti-oxidant and immunomodulatory activities. The popular inflammatory etiology of diabetes suggests that DM is a natural immune and low-grade inflammatory disease. Pharmacological intervention of the inflammatory response may provide promising and alternative approaches for the prevention and treatment of DM and its complications. Therefore, this article focuses on the potential of AS-IV in the treatment of DM from the perspective of an anti-inflammatory molecular basis. AS-IV plays a role by regulating a variety of anti-inflammatory pathways in multiple organs, tissues and target cells throughout the body. The blockade of the NF-κB inflammatory signaling pathway may be the central link of AS-IV's anti-inflammatory effect, resulting in a reduction in the tissue structure and function damage stimulated by inflammatory factors. In addition, AS-IV can delay the onset of DM and its complications by inhibiting inflammation-related oxidative stress, fibrosis and apoptosis signals. In conclusion, AS-IV has therapeutic prospects from the perspective of reducing the inflammation of DM and its complications. An in-depth study on the anti-inflammatory mechanism of AS-IV is of great significance for the effective use of Chinese herbal medicine and the promotion of its status and influence on the world.

Extracellular Vesicles and Vascular Inflammation

Vascular inflammation is the most common pathological feature in the pathogenesis of human disease. It is a complex immune process involved with many different types of cells including platelet, monocytes, macrophages, endothelial cells, and others. It is widely accepted that both innate and adaptive immune responses are important for the initiation and progression of vascular inflammation. The cell-cell interaction constitutes an important aspect of those immune responses in the vascular inflammation. Extracellular vesicles (EVs) are nanometer-sized double-layer lipid membrane vesicles released from most types of cells. They have been proved to play critical roles in intercellular communication in the occurrence and development of multisystem diseases. With the advancement of basal medical science, the biological roles of EVs in vascular inflammation have been clearer today. In this chapter, we will summarize the advance progress of extracellular vesicles in regulating vascular inflammation and its potential application in the clinical.

Hyperglycemia-induced endothelial exosomes trigger trophoblast dysregulation and abnormal placentation through PUM2-mediated repression of SOX2

BACKGROUND

Hyperglycemia is closely related to adverse pregnancy outcomes including pre-eclampsia (PE), a life-threatening complication with a substantial morbidity and mortality. However, the pathogenesis of abnormal placentation in gestational diabetes mellitus (GDM)-associated PE remains elusive.

METHOD

Here we isolated exosomes from the human umbilical vein endothelial cells (HUVECs) treated with normal level of glucose (NG) and high levels of glucose (HG). The exosomes were added to HTR-8a/SVneo cells, a trophoblast cell line. High-throughput RNA-sequencing was performed to analyzed the changed RNAs in the exosomes and exosome-treated HTR-8a/SVneo cells. HTR-8a/SVneo cell phenotypes were evaluated from the aspects of cell proliferation, cell invasion and DNA damage.

RESULTS

After treatment with HG, the changed RNAs in exosomes was enriched in RNA stabilization and oxidative stress. The altered RNAs in the HTR-8a/SVneo cells treated with exosomes from HG-induced HUVECs were enriched in pathways related to cell adhesion, migration, DNA damage response and angiogenesis. The HG-induced exosomes impaired the proliferation and invasion of HTR-8a cells and caused the DNA damage. HG up-regulated PUM2 in the exosomes and exosome-treated HTR-8a/SVneo cells. PUM2 interacted with SOX2 mRNA, resulting in the mRNA degradation. Overexpression of SOX2 prevented the damage to HTR-8a/SVneo cells caused by the exosomes from HG-induced HUVECs.

CONCLUSIONS

We demonstrate that high glucose-induced endothelial exosomes mediate abnormal phenotypes of trophoblasts through PUM2-mediated repression of SOX2. Our results reveal a novel regulatory mechanism of hyperglycemia in development of abnormal placentation and provide potential targets for preventing adverse pregnancy outcomes.

Neutrophil dynamics and inflammaging in acute ischemic stroke: A transcriptomic review

Stroke is among the leading causes of death and disability worldwide. Restoring blood flow through recanalization is currently the only acute treatment for cerebral ischemia. Unfortunately, many patients that achieve a complete recanalization fail to regain functional independence. Recent studies indicate that activation of peripheral immune cells, particularly neutrophils, may contribute to microcirculatory failure and futile recanalization. Stroke primarily affects the elderly population, and mortality after endovascular therapies is associated with advanced age. Previous analyses of differential gene expression across injury status and age identify ischemic stroke as a complex age-related disease. It also suggests robust interactions between stroke injury, aging, and inflammation on a cellular and molecular level. Understanding such interactions is crucial in developing effective protective treatments. The global stroke burden will continue to increase with a rapidly aging human population. Unfortunately, the mechanisms of age-dependent vulnerability are poorly defined. In this review, we will discuss how neutrophil-specific gene expression patterns may contribute to poor treatment responses in stroke patients. We will also discuss age-related transcriptional changes that may contribute to poor clinical outcomes and greater susceptibility to cerebrovascular diseases.

Roles of Resolvins in Chronic Inflammatory Response

An inflammatory response is beneficial to the organism, while an excessive uncontrolled inflammatory response can lead to the nonspecific killing of tissue cells. Therefore, promoting the resolution of inflammation is an important mechanism for protecting an organism suffering from chronic inflammatory diseases. Resolvins are a series of endogenous lipid mediums and have the functions of inhibiting a leukocyte infiltration, increasing macrophagocyte phagocytosis, regulating cytokines, and alleviating inflammatory pain. By promoting the inflammation resolution, resolvins play an irreplaceable role throughout the pathological process of some joint inflammation, neuroinflammation, vascular inflammation, and tissue inflammation. Although a large number of experiments have been conducted to study different subtypes of resolvins in different directions, the differences in the action targets between the different subtypes are rarely compared. Hence, this paper reviews the generation of resolvins, the characteristics of resolvins, and the actions of resolvins under a chronic inflammatory response and clinical translation of resolvins for the treatment of chronic inflammatory diseases.

Vascular Transcriptomics: Investigating Endothelial Activation and Vascular Dysfunction Using Blood Outgrowth Endothelial Cells, Organ-Chips, and RNA Sequencing

Vascular organ-chip or vessel-chip technology has significantly impacted our ability to model microphysiological vasculature. These biomimetic platforms have garnered significant interest from scientists and pharmaceutical companies as drug screening models. However, these models still lack the inclusion of patient-specific vasculature in the form of patient-derived endothelial cells. Blood outgrowth endothelial cells are patient blood-derived endothelial progenitors that have gained interest from the vascular biology community as an autologous endothelial cell alternative and have also been incorporated with the vessel-chip model. Next-generation sequencing techniques like RNA sequencing can further unlock the potential of personalized vessel-chips in discerning patient-specific hallmarks of endothelial dysfunction. Here we present a detailed protocol for (1) isolating blood outgrowth endothelial cells from patient blood samples, (2) culturing them in microfluidic vessel-chips, (3) isolating and preparing RNA from individual vessel-chips for sequencing, and (4) performing differential gene expression and bioinformatics analyses of vascular dysfunction and endothelial activation pathways. This method focuses specifically on identification of pathways and genes involved in vascular homeostasis and pathology, but can easily be adapted for the requirements of other systems. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Isolation of blood outgrowth endothelial cells from patient blood Basic Protocol 2: Culture of blood outgrowth endothelial cells in microfluidic vessel-chips Basic Protocol 3: Isolation of RNA from autologous vessel-chips Basic Protocol 4: Differential gene expression and bioinformatics analyses of endothelial activation pathways.

The Gelatinase Inhibitor ACT-03 Reduces Gliosis in the Rapid Kindling Rat Model of Epilepsy, and Attenuates Inflammation and Loss of Barrier Integrity In Vitro

Matrix metalloproteinases (MMPs) are endopeptidases responsible for the cleavage of intra- and extracellular proteins. Several brain MMPs have been implicated in neurological disorders including epilepsy. We recently showed that the novel gelatinase inhibitor ACT-03 has disease-modifying effects in models of epilepsy. Here, we studied its effects on neuroinflammation and blood–brain barrier (BBB) integrity. Using the rapid kindling rat model of epilepsy, we examined whether ACT-03 affected astro- and microgliosis in the brain using immunohistochemistry. Cellular and molecular alterations were further studied in vitro using human fetal astrocyte and brain endothelial cell (hCMEC/D3) cultures, with a focus on neuroinflammatory markers as well as on barrier permeability using an endothelial and astrocyte co-culture model. We observed less astro- and microgliosis in the brains of kindled animals treated with ACT-03 compared to control vehicle-treated animals. In vitro, ACT-03 treatment attenuated stimulation-induced mRNA expression of several pro-inflammatory factors in human fetal astrocytes and brain endothelial cells, as well as a loss of barrier integrity in endothelial and astrocyte co-cultures. Since ACT-03 has disease-modifying effects in epilepsy models, possibly via limiting gliosis, inflammation, and barrier integrity loss, it is of interest to further evaluate its effects in a clinical trial.

Wound Healing from an Actin Cytoskeletal Perspective

Wound healing requires a complex cascade of highly controlled and conserved cellular and molecular processes. These involve numerous cell types and extracellular matrix molecules regulated by the actin cytoskeleton. This microscopic network of filaments is present within the cytoplasm of all cells and provides the shape and mechanical support required for cell movement and proliferation. Here, an overview of the processes of wound healing are described from the perspective of the cell in relation to the actin cytoskeleton. Key points of discussion include the role of actin, its binding proteins, signaling pathways, and events that play significant roles in the phases of wound healing. The identification of cytoskeletal targets that can be used to manipulate and improve wound healing is included as an emerging area of focus that may inform future therapeutic approaches to improve healing of complex wounds.

Modulation of mTOR Signaling in Cardiovascular Disease to Target Acute and Chronic Inflammation

Inflammation is a key component in the pathogenesis of cardiovascular diseases causing a significant burden of morbidity and mortality worldwide. Recent research shows that mammalian target of rapamycin (mTOR) signaling plays an important role in the general and inflammation-driven mechanisms that underpin cardiovascular disease. mTOR kinase acts prominently in signaling pathways that govern essential cellular activities including growth, proliferation, motility, energy consumption, and survival. Since the development of drugs targeting mTOR, there is proven efficacy in terms of survival benefit in cancer and allograft rejection. This review presents current information and concepts of mTOR activity in myocardial infarction and atherosclerosis, two important instances of cardiovascular illness involving acute and chronic inflammation. In experimental models, inhibition of mTOR signaling reduces myocardial infarct size, enhances functional remodeling, and lowers the overall burden of atheroma. Aside from the well-known effects of mTOR inhibition, which are suppression of growth and general metabolic activity, mTOR also impacts on specific leukocyte subpopulations and inflammatory processes. Inflammatory cell abundance is decreased due to lower migratory capacity, decreased production of chemoattractants and cytokines, and attenuated proliferation. In contrast to the generally suppressed growth signals, anti-inflammatory cell types such as regulatory T cells and reparative macrophages are enriched and activated, promoting resolution of inflammation and tissue regeneration. Nonetheless, given its involvement in the control of major cellular pathways and the maintenance of a functional immune response, modification of this system necessitates a balanced and time-limited approach. Overall, this review will focus on the advancements, prospects, and limits of regulating mTOR signaling in cardiovascular disease.

Nox2 underpins microvascular inflammation and vascular contributions to cognitive decline

Chronic microvascular inflammation and oxidative stress are inter-related mechanisms underpinning white matter disease and vascular cognitive impairment (VCI). A proposed mediator is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2), a major source of reactive oxygen species (ROS) in the brain. To assess the role of Nox2 in VCI, we studied a tractable model with white matter pathology and cognitive impairment induced by bilateral carotid artery stenosis (BCAS). Mice with genetic deletion of Nox2 (Nox2 KO) were compared to wild-type (WT) following BCAS. Sustained BCAS over 12 weeks in WT mice induced Nox2 expression, indices of microvascular inflammation and oxidative damage, along with white matter pathology culminating in a marked cognitive impairment, which were all protected by Nox2 genetic deletion. Neurovascular coupling was impaired in WT mice post-BCAS and restored in Nox2 KO mice. Increased vascular expression of chemoattractant mediators, cell-adhesion molecules and endothelial activation factors in WT mice post-BCAS were ameliorated by Nox2 deficiency. The clinical relevance was confirmed by increased vascular Nox2 and indices of microvascular inflammation in human post-mortem subjects with cerebral vascular disease. Our results support Nox2 activity as a critical determinant of VCI, whose targeting may be of therapeutic benefit in cerebral vascular disease.

JAML promotes acute kidney injury mainly through a macrophage-dependent mechanism

Although macrophages are undoubtedly attractive therapeutic targets for acute kidney injury (AKI) because of their critical roles in renal inflammation and repair, the underlying mechanisms of macrophage phenotype switching and efferocytosis in the regulation of inflammatory responses during AKI are still largely unclear. The present study elucidated the role of junctional adhesion molecule–like protein (JAML) in the pathogenesis of AKI. We found that JAML was significantly upregulated in kidneys from 2 different murine AKI models including renal ischemia/reperfusion injury (IRI) and cisplatin-induced AKI. By generation of bone marrow chimeric mice, macrophage-specific and tubular cell–specific Jaml conditional knockout mice, we demonstrated JAML promoted AKI mainly via a macrophage-dependent mechanism and found that JAML-mediated macrophage phenotype polarization and efferocytosis is one of the critical signal transduction pathways linking inflammatory responses to AKI. Mechanistically, the effects of JAML on the regulation of macrophages were, at least in part, associated with a macrophage-inducible C-type lectin–dependent mechanism. Collectively, our studies explore for the first time to our knowledge new biological functions of JAML in macrophages and conclude that JAML is an important mediator and biomarker of AKI. Pharmacological targeting of JAML-mediated signaling pathways at multiple levels may provide a novel therapeutic strategy for patients with AKI.

Sphingosine-1-phosphate in mitochondrial function and metabolic diseases

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid metabolite. The past decade has witnessed exponential growth in the field of S1P research, partly attributed to drugs targeting its receptors or kinases. Accumulating evidence indicates that changes in the S1P axis (i.e., S1P production, transport, and receptors) may modify metabolism and eventually mediate metabolic diseases. Dysfunction of the mitochondria on a master monitor of cellular metabolism is considered the leading cause of metabolic diseases, with aberrations typically induced by abnormal biogenesis, respiratory chain complex disorders, reactive oxygen species overproduction, calcium deposition, and mitophagy impairment. Accordingly, we discuss decades of investigation into changes in the S1P axis and how it controls mitochondrial function. Furthermore, we summarize recent scientific advances in disorders associated with the S1P axis and their involvement in the pathogenesis of metabolic diseases in humans, including type 2 diabetes mellitus and cardiovascular disease, from the perspective of mitochondrial function. Finally, we review potential challenges and prospects for S1P axis application to the regulation of mitochondrial function and metabolic diseases; these data may provide theoretical guidance for the treatment of metabolic diseases.

H2O2 down-regulates SIRT7's protective role of endothelial premature dysfunction via microRNA-335-5p

Endothelial senescence is believed to constitute the initial pathogenesis of the atherosclerotic cardiovascular disease (ASCVD). MicroRNA-335-5p (miR-335-5p) expression is significantly up-regulated in oxidative stress-induced endothelial cells (ECs). Sirtuin7 (SIRT7) is considered to prevent EC senescence, yet data on its response to ASCVD risk factors are limited. The present study analyzed the elevated levels of miR-335-5p and the decreased levels of SIRT7 in human umbilical vein endothelial cells (HUVECs), and found that high glucose, tumor necrosis factor-α (TNF-α), and H2O2 are the three contributing factors that induced cellular senescence. The current study also assessed premature endothelial senescence and decreased proliferation, adhesion, migration, and nitric oxide (NO) secretion in HUVECs with these risk factors together with SIRT7-siRNA transfection. It found that the miR-335-5p inhibitor attenuated the down-regulation of SIRT7 expression induced by oxidative stress in HUVECs, and SIRT7 overexpression exerts a rescue effect against miR-335-5p-induced endothelial dysfunction. Furthermore, the direct binding of miR-335-5p to SIRT7 was observed in human embryonic kidney cells 293T (HEK 293T). Therefore, it can be inferred that miR-335-5p down-regulates the expression of SIRT7 in human cells. Current findings may provide deeper insights into the underlying mechanisms of endothelial senescence and potential therapeutic targets of ASCVD as well as other age-related diseases.

JAM-A is a multifaceted regulator in hepatic fibrogenesis, supporting LSEC integrity and stellate cell quiescence

BACKGROUND AND AIMS

Leukocyte infiltration is a hallmark of hepatic inflammation. The Junctional Adhesion Molecule A (JAM-A) is a crucial regulator of leukocyte extravasation and is upregulated in human viral fibrosis. Reduced shear stress within hepatic sinusoids and the specific phenotype of liver sinusoidal endothelial cells (LSEC) cumulate in differing adhesion characteristics during liver fibrosis. The aim of this study was to define the functional role of cell-specific adhesion molecule JAM-A during hepatic fibrogenesis.

METHODS

Complete, conditional (intestinal epithelial; endothelial) and bone marrow chimeric Jam-a knockout animals and corresponding C57Bl/6 wild-type animals were treated with carbon tetrachloride (CCl₄ , 6 weeks). For functional analyses of JAM-A, comprehensive in vivo studies, co-culture models and flow-based adhesion assays were performed.

RESULTS

Complete and bone marrow-derived Jam-a^-/- animals showed aggravated fibrosis with increased non-sinusoidal, perivascular accumulation of CD11b⁺ F4/80⁺ monocyte-derived macrophages in contrast to wild-type mice. Despite being associated with disturbed epithelial barrier function, an intestinal epithelial Jam-a knockout did not affect fibrogenesis. In endothelial-specific Jam-a^-/- animals, liver fibrosis was aggravated alongside sinusoid capillarization and hepatic stellate cell (HSC) activation. HSC activation is induced via Jam-a^-/- LSEC-derived secretion of soluble factors. Sinusoid CD31 expression and hedgehog gene signalling were increased, but leukocyte infiltration and adhesion to LSECs remained unaffected.

CONCLUSIONS

Our models decipher cell-specific JAM-A to exert crucial functions during hepatic fibrogenesis. JAM-A on bone marrow-derived cells regulates non-sinusoidal vascular immune cell recruitment, while endothelial JAM-A controls liver sinusoid capillarization and HSC quiescence.

Rosmarinic acid downregulates the oxLDL‑induced interaction between monocytes and endothelial cells, in addition to monocyte diapedesis, under high glucose conditions

Endothelial dysfunction during diabetes has been previously reported to be at least in part attributed to increased oxidized low‑density lipoprotein (oxLDL) levels mediated by high glucose (HG) levels. Endothelial inflammation increases the adhesiveness of monocytes to the endothelium in addition to increasing vascular permeability, promoting diabetic atherogenesis. In a previous study, it was reported that oxLDL treatment induced nucleotide‑binding domain and leucine‑rich repeat containing family, pyrin domain‑containing 3 inflammasome activation in endothelial cells (ECs) under HG conditions, in a manner that could be effectively reversed by rosmarinic acid. However, it remains unclear whether oxLDL‑mediated inflammasome activation can regulate the interaction between monocytes and ECs. The effects of oxLDL‑mediated inflammasome activation on endothelial permeability under HG conditions, in addition to the effects of rosmarinic acid on these oxLDL‑mediated processes, also remain poorly understood. Therefore, the present study aimed to elucidate the mechanisms involved in oxLDL‑induced endothelial permeability and monocyte diapedesis under HG conditions, in addition to the potential effects of rosmarinic acid. ECs were treated with oxLDL under HG conditions in the presence or absence of ROS scavengers mitoTEMPO and NAC, p38 inhibitor SB203580, FOXO1 inhibitor AS1842856 or transfected with the TXNIP siRNA, before protein expression levels of intercellular adhesion molecule 1 (ICAM‑1), vascular cell adhesion molecule‑1 (VCAM‑1), phosphorylated vascular endothelial‑cadherin (VE‑cadhedrin), VE‑cadherin and zonula occludens‑1 (ZO‑1) were measured by western blotting. In addition, adhesion assay and Transwell assays were performed. oxLDL was found to significantly increase the expression of ICAM‑1 and VCAM‑1 in ECs under HG conditions whilst also enhancing the adhesion of monocytes to ECs. This was found to be dependent on the reactive oxygen species (ROS)/p38 MAPK/forkhead box O1 (FOXO1)/thioredoxin interacting protein (TXNIP) signaling pathway. In addition, oxLDL‑stimulated ECs under HG conditions exhibited increased phosphorylated VE‑cadherin protein levels and decreased ZO‑1 protein expression levels compared with those in untreated ECs, suggesting increased endothelial permeability. Furthermore, monocyte transmigration through the endothelial monolayer was significantly increased by oxLDL treatment under HG conditions. These oxLDL‑mediated effects under HG conditions were also demonstrated to be dependent on this ROS/p38 MAPK/FOXO1/TXNIP signaling pathway. Subsequently, rosmarinic acid treatment significantly reversed oxLDL‑induced overexpression of adhesion molecules and monocyte‑EC adhesion, oxLDL‑induced endothelial junction hyperpermeability and monocyte transmigration through the endothelial monolayer under HG conditions, in a dose‑dependent manner. These results suggest that rosmarinic acid can exert a protective effect against oxLDL‑mediated endothelial dysfunction under HG conditions by reducing the interaction between monocytes and ECs in addition to preventing monocyte diapedesis.

Subsets of Cytokines and Chemokines from DENV-4-Infected Patients Could Regulate the Endothelial Integrity of Cultured Microvascular Endothelial Cells

Introduction: It is a consensus that inflammatory mediators produced by immune cells contribute to changes in endothelial permeability in dengue. We propose to relate inflammatory mediators seen in dengue patients with the in vitro alteration of endothelial cells (ECs) cultured with serum from these patients. Methods: Patients with mild (DF) to moderate and severe dengue (DFWS/Sev) were selected. ELISA quantified inflammatory mediators. Expression of adhesion molecules and CD147 were evaluated in the ECs cultured with the patient’s serum by flow cytometry. We assessed endothelial permeability by measuring transendothelial electrical resistance in cocultures of ECs with patient serum. Results: Dengue infection led to an increase in inflammatory mediators—the IL-10 distinguished DF from DFWS/Sev. There were no changes in CD31, CD54, and CD106 but decreased CD147 expression in ECs. DFWS/Sev sera induced a greater difference in endothelial permeability than DF sera. Correlation statistical test indicated that low IL-10 and IFN-γ and high CCL5 maintain the integrity of ECs in DF patients. In contrast, increased TNF, IFN-γ, CXCL8, and CCL2 maintain EC integrity in DFWS/Sev patients. Conclusions: Our preliminary data suggest that a subset of inflammatory mediators may be related to the maintenance or loss of endothelial integrity, reflecting the clinical prognosis.