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Aims: Expanded hemodialysis (HDx) therapy with improved molecular cut-off dialyzers exerts beneficial effects on lowering uremia-associated chronic systemic microinflammation, a driver of endothelial dysfunction and cardiovascular disease (CVD) in hemodialysis (HD) patients with end-stage renal disease (ESRD). However, studies on the underlying molecular mechanisms are still at an early stage. Here, we identify the (endothelial) transcription factor Krüppel-like factor 2 (KLF2) and its associated molecular signalling pathways as key targets and regulators of uremia-induced endothelial micro-inflammation in the HD/ESRD setting, which is crucial for vascular homeostasis and controlling detrimental vascular inflammation. Methods and results: First, we found that human microvascular endothelial cells (HMECs) and other typical endothelial and kidney model cell lines (e.g. HUVECs, HREC, and HEK) exposed to uremic serum from patients treated with two different hemodialysis regimens in the Permeability Enhancement to Reduce Chronic Inflammation II (PERCI-II) crossover clinical trial - comparing High-Flux (HF) and Medium Cut-Off (MCO) membranes - exhibited strongly reduced expression of vasculoprotective KLF2 with HF dialyzers, while dialysis with MCO dialyzers led to the maintenance and restoration of physiological KLF2 levels in HMECs. Mechanistic follow-up revealed that the strong downmodulation of KLF2 in HMECs exposed to uremic serum was mediated by a dominant engagement of detrimental ERK instead of beneficial AKT signalling, with subsequent AP1-/c-FOS binding in the KLF2 promoter region, followed by the detrimental triggering of pleiotropic inflammatory mediators, while the introduction of a KLF2 overexpression plasmid could restore physiological KLF2 levels and downmodulate the detrimental vascular inflammation in a mechanistic rescue approach. Conclusion: Uremia downmodulates vasculoprotective KLF2 in endothelium, leading to detrimental vascular inflammation, while MCO dialysis with the novel improved HDx therapy approach can maintain physiological levels of vasculoprotective KLF2.
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Fallo Renal Crónico , Uremia , Humanos , Células Endoteliales , Diálisis Renal/efectos adversos , Diálisis Renal/métodos , Uremia/terapia , Uremia/complicaciones , Fallo Renal Crónico/terapia , Factores de Transcripción , Inflamación/complicaciones , Factores de Transcripción de Tipo Kruppel/genéticaRESUMEN
Early identification of allograft vasculopathy and the concomitant elimination of adverse risk factors is essential for improving the long-term prognosis of heart transplant (HTx) recipients with underlying cardiovascular disease (CVD). The major aim of this pilot study was to conduct a non-invasive imaging evaluation of the HTx patient microcirculation by employing nailfold video-capillaroscopy (NVC) in a well-characterized patient and control cohort, and to correlate these data with endothelial cell function, accompanied by studies of traditional cardiovascular risk factors and non-HLA antibodies in HTx recipients. Ten patients undergoing HTx (mean age of 38 ± 14 years) were recruited for the study and compared to a control group of 12 well-matched healthy volunteers (mean age 35 ± 5 years) with normal body mass index (BMI). Detailed medical records were collected from all individuals. NVC was performed using CapillaryScope 200 MEDL4N microscope. For functional readout and correlation analysis, endothelial cell network formation in conjunction with measurements of patient serum levels of vascular endothelial growth factor (VEGF) and non-HLA autoantibodies directed against the angiotensin II type-1-receptor (anti-AT1R-Ab), endothelin-1 type-A-receptor (anti-ETAR-Ab), protease-activated receptor-1 (anti-PAR-1-Ab), and VEGF-A (anti-VEGF-A-Ab) were studied. Our NVC analysis found that the average apical loop diameter of nailfold capillaries was significantly increased in HTx recipients (p = 0.001). In addition, HTx patients with more prominent changes in capillaroscopic patterns were characterized by the presence of traditional cardiovascular risk factors, and HTx patients had increased levels of anti-AT1R-ab, anti-ETAR-ab, and anti-VEGF-A-Ab (p = 0.017, p = 0.025, and p = 0.003, respectively). Capillary diameters most strongly correlated with elevated serum levels of troponin T and triglycerides (R = 0.69, p = 0.028 and R = 0.81, p = 0.004, respectively). In conclusion, we found that an abnormal NVC pattern in HTx patients is associated with traditional CVD risk factors and that NVC is a useful non-invasive tool to conveniently monitor changes in the microvasculature of HTx patients.
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This publication has been retracted by the Editor due to non-original content and deficiencies in the conduct of the study. Reference: Dashan Wu, Jiawei Lin, Yingbin Zhu, Haotian Zhang, Yuanfu Zhong. Expression of Testis-Specific Gene Antigen 10 (TSGA10) is Associated with Apoptosis and Cell Migration in Bladder Cancer Cells and Tumor Stage and Overall Survival in Patients with Bladder Cancer. Med Sci Monit, 2019; 25: 5289-5298. DOI: 10.12659/MSM.915682.
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Peritoneal dialysis (PD) is a valuable 'home treatment' option, even more so during the ongoing Coronavirus pandemic. However, the long-term use of PD is limited by unfavourable tissue remodelling in the peritoneal membrane, which is associated with inflammation-induced angiogenesis. This appears to be driven primarily through vascular endothelial growth factor (VEGF), while the involvement of other angiogenic signaling pathways is still poorly understood. Here, we have identified the crucial contribution of mesothelial cell-derived angiogenic CXC chemokine ligand 1 (CXCL1) to peritoneal angiogenesis in PD. CXCL1 expression and peritoneal microvessel density were analysed in biopsies obtained by the International Peritoneal Biobank (NCT01893710 at www.clinicaltrials.gov), comparing 13 children with end-stage kidney disease before initiating PD to 43 children on chronic PD. The angiogenic potential of mesothelial cell-derived CXCL1 was assessed in vitro by measuring endothelial tube formation of human microvascular endothelial cells (HMECs) treated with conditioned medium from human peritoneal mesothelial cells (HPMCs) stimulated to release CXCL1 by treatment with either recombinant IL-17 or PD effluent. We found that the capillary density in the human peritoneum correlated with local CXCL1 expression. Both CXCL1 expression and microvessel density were higher in PD patients than in the age-matched patients prior to initiation of PD. Exposure of HMECs to recombinant CXCL1 or conditioned medium from IL-17-stimulated HPMCs resulted in increased endothelial tube formation, while selective inhibition of mesothelial CXCL1 production by specific antibodies or through silencing of relevant transcription factors abolished the proangiogenic effect of HPMC-conditioned medium. In conclusion, peritoneal mesothelium-derived CXCL1 promotes endothelial tube formation in vitro and associates with peritoneal microvessel density in uremic patients undergoing PD, thus providing novel targets for therapeutic intervention to prolong PD therapy.
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Quimiocina CXCL1/metabolismo , Neovascularización Patológica/patología , Diálisis Peritoneal/métodos , Peritoneo/irrigación sanguínea , Terapia de Reemplazo Renal/métodos , COVID-19/patología , Células Cultivadas , Niño , Preescolar , Epitelio/metabolismo , Humanos , Lactante , Interleucina-17/metabolismo , Fallo Renal Crónico/terapia , Peritoneo/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Remodelación Vascular/fisiologíaRESUMEN
Atherosclerotic artery disease is the major cause of death and an immense burden on healthcare systems worldwide. The formation of atherosclerotic plaques is promoted by high levels of low-density lipoproteins (LDL) in the blood, especially in the oxidized form. Circulating LDL is taken up by conventional and non-classical endothelial cell receptors and deposited in the vessel wall. The exact mechanism of LDL interaction with vascular endothelial cells is not fully understood. Moreover, it appears to depend on the type and location of the vessel affected and the receptor involved. Here, we analyze how native LDL (nLDL) and oxidized LDL (oxLDL) modulate the expression of their receptors-classical LDLR and alternative LOX-1-in endothelial cells derived from human umbilical artery (HUAECs), used as an example of a medium-sized vessel, which is typically affected by atherosclerosis. Exposure of HUAECs to nLDL resulted in moderate nLDL uptake and gradual increase in LDLR, but not LOX-1, expression over 24 h. Conversely, exposure of HUAECs to oxLDL, led to significant accumulation of oxLDL and rapid induction of LOX-1, but not LDLR, within 7 h. These activation processes were associated with phosphorylation of protein kinases ERK1/2 and p38, followed by activation of the transcription factor AP-1 and its binding to the promoters of the respective receptor genes. Both nLDL-induced LDLR mRNA expression and oxLDL-induced LOX-1 mRNA expression were abolished by blocking ERK1/2, p-38 or AP-1. In addition, oxLDL, but not nLDL, was capable of inducing LOX-1 through the NF-κB-controlled pathway. These observations indicate that in arterial endothelial cells nLDL and oxLDL signal mainly via LDLR and LOX-1 receptors, respectively, and engage ERK1/2 and p38 kinases, and AP-1, as well as NF-κB transcription factors to exert feed-forward regulation and increase the expression of these receptors, which may perpetuate endothelial dysfunction in atherosclerosis.
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Células Endoteliales/metabolismo , Regulación de la Expresión Génica , Lipoproteínas LDL/farmacología , Receptores de LDL/metabolismo , Receptores Depuradores de Clase E/metabolismo , Arterias Umbilicales/citología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/metabolismo , Oxidación-Reducción , Regiones Promotoras Genéticas/genética , Receptores de LDL/genética , Receptores Depuradores de Clase E/genética , Factor de Transcripción AP-1/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
BACKGROUND: Scleroderma renal crisis (SRC) is a life-threatening complication of systemic sclerosis (SSc). Autoantibodies (Abs) against endothelial cell antigens have been implicated in SSc and SRC. However, their detailed roles remain poorly defined. Pro-inflammatory cytokine interleukin-6 (IL-6) has been found to be increased in SSc, but its role in SRC is unclear. Here, we aimed to determine how the autoantibodies from patients with SSc and SRC affect IL-6 secretion by micro-vascular endothelial cells (HMECs). METHODS: Serum IgG fractions were isolated from either SSc patients with SRC (n = 4) or healthy individuals (n = 4) and then each experiment with HMECs was performed with SSc-IgG from a separate patient or separate healthy control. IL-6 expression and release by HMECs was assessed by quantitative reverse transcription and quantitative PCR (RT-qPCR) and immunoassays, respectively. The mechanisms underlying the production of IL-6 were analyzed by transient HMEC transfections with IL-6 promoter constructs, electrophoretic mobility shift assays, Western blots and flow cytometry. RESULTS: Exposure of HMECs to IgG from SSc patients, but not from healthy controls, resulted in a time- and dose-dependent increase in IL-6 secretion, which was associated with increased AKT, p70S6K, and ERK1/2 signalling, as well as increased c-FOS/AP-1 transcriptional activity. All these effects could be reduced by the blockade of the endothelial PAR-1 receptor and/or c-FOS/AP-1silencing. CONCLUSIONS: Autoantibodies against PAR-1 found in patients with SSc and SRC induce IL-6 production by endothelial cells through signalling pathways controlled by the AP-1 transcription factor. These observations offer a greater understanding of adverse endothelial cell responses to autoantibodies present in patients with SRC.
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Autoanticuerpos/inmunología , Células Endoteliales/inmunología , Interleucina-6/inmunología , Enfermedades Renales/inmunología , Sistema de Señalización de MAP Quinasas/inmunología , Receptor PAR-1/inmunología , Esclerodermia Sistémica/inmunología , Adulto , Línea Celular , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Thrombin, the ligand of the protease-activated receptor 1 (PAR1), is a well-known stimulator of proangiogenic responses in vascular endothelial cells (ECs), which are mediated through the induction of vascular endothelial growth factor (VEGF). However, the transcriptional events underlying this thrombin-induced VEGF induction and angiogenic response are less well understood at present. As reported here, we conducted detailed promotor activation and signal transduction pathway studies in human microvascular ECs, to decipher the transcription factors and the intracellular signaling events underlying the thrombin and PAR-1-induced endothelial VEGF induction. We found that c-FOS is a key transcription factor controlling thrombin-induced EC VEGF synthesis and angiogenesis. Upon the binding and internalization of its G-protein-coupled PAR-1 receptor, thrombin triggers ERK1/2 signaling and activation of the nuclear AP-1/c-FOS transcription factor complex, which then leads to VEGF transcription, extracellular secretion, and concomitant proangiogenic responses of ECs. In conclusion, exposure of human microvascular ECs to thrombin triggers signaling through the PAR-1-ERK1/2-AP-1/c-FOS axis to control VEGF gene transcription and VEGF-induced angiogenesis. These observations offer a greater understanding of endothelial responses to thromboinflammation, which may help to interpret the results of clinical trials tackling the conditions associated with endothelial injury and thrombosis.
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Regulación de la Expresión Génica , Neovascularización Fisiológica/genética , Trombina/farmacología , Transcripción Genética/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Microvasos/patología , Neovascularización Fisiológica/efectos de los fármacos , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-jun/metabolismo , Receptor PAR-1/metabolismo , Factor de Transcripción AP-1/metabolismo , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
BACKGROUND Testis-specific gene antigen 10 (TSGA10) is a tumor suppressor in several types of human malignancy. However, there have been few studies that have investigated the role of TSGA10 in bladder cancer. This study aimed to investigate the expression of TSGA10 in human bladder cancer cell lines and bladder cancer tissues and its effects on patient prognosis. MATERIAL AND METHODS The expression of TSGA10 in 40 tissue samples of bladder cancer and matched normal adjacent bladder tissue, and five human bladder cancer cell lines was assessed by immunohistochemistry, Western blot, quantitative reverse transcription polymerase chain reaction (qRT-PCR), and flow cytometry. The correlation between the expression level of TSGA10 and the clinicopathological features of patients with bladder cancer was analyzed and overall survival (OS) in patients with bladder cancer was determined by Kaplan-Meier curves. RESULTS Upregulation of TSGA10 expression in tissues from patients with bladder cancer was compared with normal adjacent bladder tissue and was significantly correlated with gender, metastasis, lymphovascular invasion, and tumor stage in bladder cancer. In bladder cancer cell lines, down-regulation of TSGA10 reduced cell apoptosis and increased cell migration, and resulted in the formation of an epithelial-mesenchymal transition (EMT) phenotype. Overexpression of TSGA10 resulted in an increased apoptosis rate of tumor cells, reduced cell migration, and contributed to the reversal of the EMT phenotype. CONCLUSIONS These findings support that TSGA10 deserves further study as a potential novel prognostic biomarker in bladder cancer.