RESUMO
Upon inflammation, leukocytes leave the circulation by crossing the endothelial monolayer at specific transmigration "hotspot" regions. Although these regions support leukocyte transmigration, their functionality is not clear. We found that endothelial hotspots function to limit vascular leakage during transmigration events. Using the photoconvertible probe mEos4b, we traced back and identified original endothelial transmigration hotspots. Using this method, we show that the heterogeneous distribution of ICAM-1 determines the location of the transmigration hotspot. Interestingly, the loss of ICAM-1 heterogeneity either by CRISPR/Cas9-induced knockout of ICAM-1 or equalizing the distribution of ICAM-1 in all endothelial cells results in the loss of TEM hotspots but not necessarily in reduced TEM events. Functionally, the loss of endothelial hotspots results in increased vascular leakage during TEM. Mechanistically, we demonstrate that the 3 extracellular Ig-like domains of ICAM-1 are crucial for hotspot recognition. However, the intracellular tail of ICAM-1 and the 4th Ig-like dimerization domain are not involved, indicating that intracellular signaling or ICAM-1 dimerization is not required for hotspot recognition. Together, we discovered that hotspots function to limit vascular leakage during inflammation-induced extravasation.
Assuntos
Molécula 1 de Adesão Intercelular , Migração Transendotelial e Transepitelial , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Células Endoteliais/metabolismo , Leucócitos/metabolismo , Transdução de Sinais , Endotélio Vascular/metabolismo , Movimento Celular , Adesão CelularRESUMO
Chronic kidney disease (CKD) has emerged as a significant global public health concern. Recent epidemiological studies have highlighted the link between exposure to fine particulate matter (PM2.5) and a decline in renal function. PM2.5 exerts harmful effects on various organs through oxidative stress and inflammation. Acute kidney injury (AKI) resulting from ischaemia-reperfusion injury (IRI) involves biological processes similar to those involved in PM2.5 toxicity and is a known risk factor for CKD. The objective of this study was to investigate the impact of PM2.5 exposure on IRI-induced AKI. Through a unique environmentally controlled setup, mice were exposed to urban PM2.5 or filtered air for 12 weeks before IRI followed by euthanasia 48 h after surgery. Animals exposed to PM2.5 and IRI exhibited reduced glomerular filtration, impaired urine concentration ability, and significant tubular damage. Further, PM2.5 aggravated local innate immune responses and mitochondrial dysfunction, as well as enhancing cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway activation. This increased renal senescence and suppressed the anti-ageing protein klotho, leading to early fibrotic changes. In vitro studies using proximal tubular epithelial cells exposed to PM2.5 and hypoxia/reoxygenation revealed heightened activation of the STING pathway triggered by cytoplasmic mitochondrial DNA, resulting in increased tubular damage and a pro-inflammatory phenotype. In summary, our findings imply a role for PM2.5 in sensitising proximal tubular epithelial cells to IRI-induced damage, suggesting a plausible association between PM2.5 exposure and heightened susceptibility to CKD in individuals experiencing AKI. Strategies aimed at reducing PM2.5 concentrations and implementing preventive measures may improve outcomes for AKI patients and mitigate the progression from AKI to CKD. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Injúria Renal Aguda , Camundongos Endogâmicos C57BL , Material Particulado , Traumatismo por Reperfusão , Animais , Injúria Renal Aguda/patologia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Traumatismo por Reperfusão/patologia , Material Particulado/efeitos adversos , Material Particulado/toxicidade , Camundongos , Masculino , Poluição do Ar/efeitos adversos , Modelos Animais de Doenças , Rim/patologia , Rim/metabolismo , Transdução de Sinais , Taxa de Filtração GlomerularRESUMO
BACKGROUND: Acute respiratory distress syndrome (ARDS) is characterized by alveolar edema that can progress to septal fibrosis. Mechanical ventilation can augment lung injury, termed ventilator-induced lung injury (VILI). Connective tissue growth factor (CTGF), a mediator of fibrosis, is increased in ARDS patients. Blocking CTGF inhibits fibrosis and possibly vascular leakage. This study investigated whether neutralizing CTGF reduces pulmonary edema in VILI. METHODS: Following LPS administration, rats were mechanically ventilated for 6 h with low (6 mL/kg; low VT) or moderate (10 mL/kg; mod VT) tidal volume and treated with a neutralizing CTGF antibody (FG-3154) or placebo lgG (vehicle). Control rats without LPS were ventilated for 6 h with low VT. Lung wet-to-dry weight ratio, FITC-labeled dextran permeability, histopathology, and soluble RAGE were determined. RESULTS: VILI was characterized by reduced PaO2/FiO2 ratio (low VT: 540 [381-661] vs. control: 693 [620-754], p < 0.05), increased wet-to-dry weight ratio (low VT: 4.8 [4.6-4.9] vs. control: 4.5 [4.4-4.6], p < 0.05), pneumonia (low VT: 30 [0-58] vs. control: 0 [0-0]%, p < 0.05) and interstitial inflammation (low VT: 2 [1-3] vs. control: 1 [0-1], p < 0.05). FG-3154 did not affect wet-to-dry weight ratio (mod VT + FG-3154: 4.8 [4.7-5.0] vs. mod VT + vehicle: 4.8 [4.8-5.0], p > 0.99), extravasated dextrans (mod VT + FG-3154: 0.06 [0.04-0.09] vs. mod VT + vehicle: 0.04 [0.03-0.09] µg/mg tissue, p > 0.99), sRAGE (mod VT + FG-3154: 1865 [1628-2252] vs. mod VT + vehicle: 1885 [1695-2159] pg/mL, p > 0.99) or histopathology. CONCLUSIONS: 'Double hit' VILI was characterized by inflammation, impaired oxygenation, pulmonary edema and histopathological lung injury. Blocking CTGF does not improve oxygenation nor reduce pulmonary edema in rats with VILI.
Assuntos
Fator de Crescimento do Tecido Conjuntivo , Edema Pulmonar , Lesão Pulmonar Induzida por Ventilação Mecânica , Animais , Lesão Pulmonar Induzida por Ventilação Mecânica/tratamento farmacológico , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Ratos , Masculino , Edema Pulmonar/etiologia , Edema Pulmonar/metabolismo , Anticorpos Neutralizantes/farmacologia , Ratos Sprague-Dawley , Pulmão/patologia , Pulmão/metabolismo , Modelos Animais de Doenças , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidoresRESUMO
The mechanism of action of bronchial thermoplasty (BT) treatment for patients with severe asthma is incompletely understood. This study investigated the 2.5-year impact of BT on airway smooth muscle (ASM) mass and clinical parameters by paired data analysis in 22 patients. Our findings demonstrate the persistence of ASM mass reduction of >50% after 2.5 years. Furthermore, sustained improvement in asthma control, quality of life and exacerbation rates was found, which is in line with previous reports. An association was found between the remaining ASM and both the exacerbation rate (r=0.61, p=0.04 for desmin, r=0.85, p<0.01 for alpha smooth muscle actin (SMA)) and post-bronchodilator forced expiratory volume in 1 s predicted percentage (r=-0.69, p=0.03 for desmin, r=-0.58, p=0.08 for alpha SMA). This study provides new insight into the long-term impact of BT.
Assuntos
Asma , Termoplastia Brônquica , Humanos , Brônquios/cirurgia , Qualidade de Vida , Desmina/uso terapêutico , Asma/tratamento farmacológico , Resultado do Tratamento , Músculo LisoRESUMO
BACKGROUND AND HYPOTHESIS: The decision for acceptance or discard of the increasingly rare and marginal brain-dead donor kidneys in Eurotransplant (ET) countries has to be made without solid evidence. Thus, we developed and validated flexible clinicopathological scores called 2-Step Scores for the prognosis of delayed graft function (DGF) and one-year death-censored transplant loss (1y-tl) reflecting the current practice of six ET countries including Croatia and Belgium. METHODS: The training set was n=620 for DGF and n=711 for 1y-tl, with validation sets n=158 and n=162. In step 1, stepwise logistic regression models including only clinical predictors were used to estimate the risks. In step 2, risk estimates were updated for statistically relevant intermediate risk percentiles with nephropathology. RESULTS: Step 1 revealed an increased risk of DGF with increased cold ischaemia time, donor and recipient BMI, dialysis vintage, number of HLA-DR mismatches or recipient CMV IgG positivity. On the training and validation set, c-statistics were 0.672 and 0.704, respectively. At a range between 18% and 36%, accuracy of DGF-prognostication improved with nephropathology including number of glomeruli and Banff cv (updated overall c statistics of 0.696 and 0.701, respectively).Risk of 1y-tl increased in recipients with cold ischaemia time, sum of HLA-A. -B, -DR mismatches and donor age. On training and validation sets, c-statistics were 0.700 and 0.769, respectively. Accuracy of 1y-tl prediction improved (c-statistics = 0.706 and 0.765) with Banff ct. Overall, calibration was good on the training, but moderate on the validation set; discrimination was at least as good as established scores when applied to the validation set. CONCLUSION: Our flexible 2-Step Scores with optional inclusion of time-consuming and often unavailable nephropathology should yield good results for clinical practice in ET, and may be superior to established scores. Our scores are adaptable to donation after cardiac death and perfusion pump use.
RESUMO
BACKGROUND: Immunoglobulin A vasculitis with nephritis (IgAVN) is the most common vasculitis in children. Due to a lack of evidence, treatment recommendations are based on expert opinion, resulting in variation. The aim of this study was to describe the clinical presentation, treatment and outcome of an extremely large cohort of children with biopsy-proven IgAVN in order to identify prognostic risk factors and signals of treatment efficacy. METHODS: Retrospective data were collected on 1148 children with biopsy-proven IgAVN between 2005 and 2019 from 41 international paediatric nephrology centres across 25 countries and analysed using multivariate analysis. The primary outcome was estimated glomerular filtration rate (eGFR) and persistent proteinuria at last follow-up. RESULTS: The median follow-up was 3.7 years (interquartile range 2-6.2). At last follow-up, 29% of patients had an eGFR <90 mL/min/1.73 m2, 36% had proteinuria and 3% had chronic kidney disease stage 4-5. Older age, lower eGFR at onset, hypertension and histological features of tubular atrophy and segmental sclerosis were predictors of poor outcome. There was no evidence to support any specific second-line immunosuppressive regimen being superior to others, even when further analysing subgroups of children with reduced kidney function, nephrotic syndrome or hypoalbuminemia at onset. Delayed start of immunosuppressive treatment was associated with a lower eGFR at last follow-up. CONCLUSION: In this large retrospective cohort, key features associated with disease outcome are highlighted. Importantly, there was no evidence to support that any specific immunosuppressive treatments were superior to others. Further discovery science and well-conducted clinical trials are needed to define accurate treatment and improve outcomes of IgAVN.
Assuntos
Taxa de Filtração Glomerular , Imunossupressores , Humanos , Masculino , Criança , Feminino , Estudos Retrospectivos , Adolescente , Imunossupressores/uso terapêutico , Pré-Escolar , Prognóstico , Glomerulonefrite por IGA/tratamento farmacológico , Glomerulonefrite por IGA/patologia , Seguimentos , Terapia de Imunossupressão/métodos , Vasculite por IgA/tratamento farmacológico , Vasculite por IgA/complicações , Vasculite por IgA/diagnóstico , Resultado do Tratamento , Vasculite/tratamento farmacológicoRESUMO
DNA methyltransferase (Dnmt)3b mediates de novo DNA methylation and modulation of Dnmt3b in respiratory epithelial cells has been shown to affect the expression of multiple genes. Respiratory epithelial cells provide a first line of defense against pulmonary pathogens and play a crucial role in the immune response during pneumonia caused by Pseudomonas (P.) aeruginosa, a gram-negative bacterium that expresses flagellin as an important virulence factor. We here sought to determine the role of Dntm3b in respiratory epithelial cells in immune responses elicited by P. aeruginosa. DNMT3B expression was reduced in human bronchial epithelial (BEAS-2B) cells as well as in primary human and mouse bronchial epithelial cells grown in air liquid interface upon exposure to P. aeruginosa (PAK). Dnmt3b deficient human bronchial epithelial (BEAS-2B) cells produced more CXCL1, CXCL8 and CCL20 than control cells when stimulated with PAK, flagellin-deficient PAK (PAKflic) or flagellin. Dnmt3b deficiency reduced DNA methylation at exon 1 of CXCL1 and enhanced NF-ĸB p65 binding to the CXCL1 promoter. Mice with bronchial epithelial Dntm3b deficiency showed increased Cxcl1 mRNA expression in bronchial epithelium and CXCL1 protein release in the airways during pneumonia caused by PAK, which was associated with enhanced neutrophil recruitment and accelerated bacterial clearance; bronchial epithelial Dnmt3b deficiency did not modify responses during pneumonia caused by PAKflic or Klebsiella pneumoniae (an un-flagellated gram-negative bacterium). Dnmt3b deficiency in type II alveolar epithelial cells did not affect mouse pulmonary defense against PAK infection. These results suggest that bronchial epithelial Dnmt3b impairs host defense during Pseudomonas induced pneumonia, at least in part, by dampening mucosal responses to flagellin.
Assuntos
DNA (Citosina-5-)-Metiltransferases/imunologia , Pneumonia Bacteriana/imunologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/microbiologia , Animais , Brônquios/imunologia , Brônquios/microbiologia , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Flagelina/imunologia , Humanos , Imunidade , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Infiltração de Neutrófilos , Pneumonia Bacteriana/microbiologia , Infecções por Pseudomonas/microbiologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/microbiologia , DNA Metiltransferase 3BRESUMO
BACKGROUND AND OBJECTIVES: Transfusion-associated circulatory overload (TACO) is a pulmonary transfusion complication and a leading cause of transfusion-related morbidity and mortality. Volume overload and rising hydrostatic pressure as a consequence of transfusion are seen as the central pathway leading to TACO. A possible preventative measure for TACO could be the use of low-volume blood products like volume-reduced lyophilized plasma. We hypothesize that volume-reduced lyophilized plasma decreases circulatory overload leading to a reduced pulmonary capillary pressure and can therefore be an effective strategy to prevent TACO. MATERIALS AND METHODS: A validated two-hit animal model in rats with heart failure was used. Animals were randomized to receive 4 units of either solvent-detergent pooled plasma (SDP) as control, standard volume lyophilized plasma (LP-S) or hyperoncotic volume-reduced lyophilized plasma (LP-VR). The primary outcome was the difference between pre-transfusion and post-transfusion left ventricular end-diastolic pressure (ΔLVEDP). Secondary outcomes included markers for acute lung injury. RESULTS: LVEDP increased in all randomization groups following transfusion. The greatest elevation was seen in the group receiving LP-VR (+11.9 mmHg [5.9-15.6]), but there were no significant differences when compared to groups receiving either LP-S (+6.3 mmHg [2.9-13.4], p = 0.29) or SDP (+7.7 mmHg [4.5-10.5], p = 0.55). There were no significant differences in markers for acute lung injury, such as pulmonary wet/dry weight ratios, lung histopathology scores or PaO2 /FiO2 ratio between the three groups. CONCLUSION: Transfusion with hyperoncotic volume-reduced plasma did not attenuate circulatory overload compared to standard volume plasma and was therefore not an effective preventative strategy for TACO in this rat model.
Assuntos
Lesão Pulmonar Aguda , Reação Transfusional , Animais , Ratos , Lesão Pulmonar Aguda/etiologia , Transfusão de Sangue , Modelos Animais , Plasma , Reação Transfusional/etiologiaRESUMO
BACKGROUND: Trauma-induced coagulopathy is associated with platelet dysfunction and contributes to early mortality after traumatic injury. Plasma concentrations of the damage molecule high-mobility group box-1 (HMGB-1) increase after trauma, which may contribute to platelet dysfunction. We hypothesised that inhibition of HMGB-1 with a monoclonal antibody (mAb) or with recombinant thrombomodulin (rTM) improves trauma-induced coagulopathy in a murine model of trauma and shock. METHODS: Male 129S2/SvPasOrlRJ mice were anaesthetised, mechanically ventilated, and randomised into five groups: (i) ventilation control (VENT), (ii) trauma/shock (TS), (iii) TS+anti-HMGB-1 mAb (TS+AB), (iv) TS+rTM (TS+TM), and (v) TS+anti-HMGB-1 mAb+rTM (TS+COMBI). Primary outcome was rotational thromboelastometry EXTEM. Secondary outcomes included tail bleeding time, platelet count, plasma HMGB-1 concentration, and platelet activation. RESULTS: Trauma and shock resulted in a hypocoagulable thromboelastometry profile, increased plasma HMGB-1, and increased platelet activation markers. TS+AB was associated with improved clot firmness after 5 min compared with TS (34 [33-37] vs 32 [29-34] mm; P=0.043). TS+COMBI was associated with decreased clot formation time (98 [92-125] vs 122 [111-148] s; P=0.018) and increased alpha angle (77 [72-78] vs 69 [64-71] degrees; P=0.003) compared with TS. TS+COMBI also reduced tail bleeding time compared with TS (P=0.007). The TS+TM and TS+COMBI groups had higher platelet counts compared with TS (P=0.044 and P=0.041, respectively). CONCLUSIONS: Inhibition of HMGB-1 early after trauma in a mouse model improves clot formation and strength, preserves platelet count, and decreases bleeding time.
Assuntos
Transtornos da Coagulação Sanguínea , Choque , Masculino , Camundongos , Animais , Modelos Animais de Doenças , Transtornos da Coagulação Sanguínea/etiologia , Transtornos da Coagulação Sanguínea/terapia , Testes de Coagulação Sanguínea , Tromboelastografia/métodos , HemorragiaRESUMO
Pancreatic ductal adenocarcinoma (PDAC) is a dismal disease with a poor clinical prognosis and unsatisfactory treatment options. We previously found that the transcription factor CCAAT/Enhancer-Binding Protein Delta (C/EBPδ) is lowly expressed in PDAC compared to healthy pancreas duct cells, and that patient survival and lymph node involvement in PDAC is correlated with the expression of C/EBPδ in primary tumor cells. C/EBPδ shares a homologous DNA-binding sequence with other C/EBP-proteins, leading to the presumption that other C/EBP-family members might act redundantly and compensate for the loss of C/EBPδ. This implies that patient stratification could be improved when expression levels of multiple C/EBP-family members are considered simultaneously. In this study, we assessed whether the quantification of C/EBPß or C/EBPγ in addition to that of C/EBPδ might improve the prediction of patient survival and lymph node involvement using a cohort of 68 resectable PDAC patients. Using Kaplan-Meier analyses of patient groups with different C/EBP-expression levels, we found that both C/EBPß and C/EBPγ can partially compensate for low C/EBPδ and improve patient survival. Further, we uncovered C/EBPß as a novel predictor of a decreased likelihood of lymph node involvement in PDAC, and found that C/EBPß and C/EBPδ can compensate for the lack of each other in order to reduce the risk of lymph node involvement. C/EBPγ, on the other hand, appears to promote lymph node involvement in the absence of C/EBPδ. Altogether, our results show that the redundancy of C/EBP-family members might have a profound influence on clinical prognoses and that the expression of both C/EPBß and C/EBPγ should be taken into account when dichotomizing patients according to C/EBPδ expression.
Assuntos
Proteínas Estimuladoras de Ligação a CCAAT , Carcinoma Ductal Pancreático , Regulação da Expressão Gênica , Neoplasias Pancreáticas , Humanos , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT/genética , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Linfonodos/metabolismo , Linfonodos/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Metástase Linfática/genética , Metástase Linfática/patologia , Metástase Linfática/fisiopatologia , PrognósticoRESUMO
BACKGROUND: Liver kinase B1 (LKB1) has been studied extensively as a tumor suppressor gene (Stk11) in the context of cancer. We hypothesized that myeloid LKB1 plays a role in innate immunity during pneumonia. METHODS: Mice deficient for LKB1 in myeloid cells (LysM-cre × Stk11fl/fl) or neutrophils (Mrp8-cre × Stk11fl/fl) were infected with Klebsiella pneumoniae via the airways. LysM-cre × Stk11fl/fl mice were also intranasally challenged with lipopolysaccharide (LPS). RESULTS: Mice with myeloid LKB1 deficiency, but not those with neutrophil LKB1 deficiency, had increased bacterial loads in lungs 6-40 hours after infection, compared with control mice, pointing to a role for LKB1 in macrophages. Myeloid LKB1 deficiency was associated with reduced cytokine release into the airways on local LPS instillation. The number of classic (SiglecFhighCD11bneg) alveolar macrophages (AMs) was reduced by approximately 50% in the lungs of myeloid LKB1-deficient mice, which was not caused by increased cell death or reduced proliferation. Instead, these mice had AMs with a "nonclassic" (SiglecFlowCD11bpos) phenotype. AMs did not up-regulate glycolysis in response to LPS, irrespective of LKB1 presence. CONCLUSION: Myeloid LKB1 is important for local host defense during Klebsiella pneumonia by maintaining adequate AM numbers in the lung.
Assuntos
Infecções por Klebsiella , Pneumonia Bacteriana , Animais , Infecções por Klebsiella/microbiologia , Fígado/patologia , Macrófagos Alveolares , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Peritonitis and abdominal sepsis remain major health problems and challenge for clinicians. Bruton's tyrosine kinase (Btk) is a versatile signaling protein involved in the regulation of B cell development and function, as well as innate host defense. In the current study, we aimed to explore the role of Btk in the host response during peritonitis and sepsis in mice induced by a gradually growing pathogenic strain of Escherichia coli bacteria. We found that Btk deficiency ameliorated antibacterial host defense during the late stage of E. coli-induced peritonitis. Btk was not required for cytokine and chemokine release in response to either E. coli or lipopolysaccharide and did not impact organ damage evoked by E. coli. Btk deficiency also did not alter neutrophil influx to the primary site of infection. However, the absence of Btk modestly enhanced phagocytosis of E. coli by neutrophils. These results indicate that Btk-mediated signaling is superfluous for inflammatory responses and remarkably detrimental for antibacterial defense during E. coli-induced peritonitis.
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Anti-Infecciosos , Infecções por Escherichia coli , Peritonite , Sepse , Tirosina Quinase da Agamaglobulinemia/metabolismo , Animais , Antibacterianos , Escherichia coli/metabolismo , CamundongosRESUMO
BACKGROUND: Liver kinase B1 (Lkb1, gene name Stk11) functions as a tumor suppressor in cancer. Myeloid cell Lkb1 potentiates lung inflammation induced by the Gram-negative bacterial cell wall component lipopolysaccharide and in host defense during Gram-negative pneumonia. Here, we sought to investigate the role of myeloid Lkb1 in lung inflammation elicited by the Gram-positive bacterial cell wall component lipoteichoic acid (LTA) and during pneumonia caused by the Gram-positive respiratory pathogen Streptococcus pneumoniae (Spneu). METHODS: Alveolar and bone marrow derived macrophages (AMs, BMDMs) harvested from myeloid-specific Lkb1 deficient (Stk11-ΔM) and littermate control mice were stimulated with LTA or Spneu in vitro. Stk11-ΔM and control mice were challenged via the airways with LTA or infected with Spneu in vivo. RESULTS: Lkb1 deficient AMs and BMDMs produced less tumor necrosis factor (TNF)α upon activation by LTA or Spneu. During LTA-induced lung inflammation, Stk11-ΔM mice had reduced numbers of AMs in the lungs, as well as diminished cytokine release and neutrophil recruitment into the airways. During pneumonia induced by either encapsulated or non-encapsulated Spneu, Stk11-ΔM and control mice had comparable bacterial loads and inflammatory responses in the lung, with the exception of lower TNFα levels in Stk11-ΔM mice after infection with the non-encapsulated strain. CONCLUSION: Myeloid Lkb1 contributes to LTA-induced lung inflammation, but is not important for host defense during pneumococcal pneumonia.
Assuntos
Pneumonia Bacteriana , Pneumonia Pneumocócica , Streptococcus pneumoniae , Proteínas Quinases Ativadas por AMP , Animais , Lipopolissacarídeos/imunologia , Fígado , Camundongos , Pneumonia Bacteriana/induzido quimicamente , Streptococcus pneumoniae/patogenicidade , Ácidos Teicoicos , Fator de Necrose Tumoral alfaRESUMO
BACKGROUND AND OBJECTIVES: Transfusion-associated circulatory overload (TACO) is the primary cause of transfusion-related mortality. Speed and volume of transfusion are major risk factors. The aim of this study was to investigate the interaction of red blood cell (RBC) transfusion speed and volume on the development of TACO. MATERIALS AND METHODS: A validated model for TACO in anaemic Lewis rats with an acute myocardial infarction was used. The effect on pulmonary hydrostatic pressure of one, two or four units of packed RBCs transfused in either 30 or 60 min was evaluated (3.3-26.6 ml·kg-1 ·hr-1 ). Pulmonary capillary pressure was measured as left ventricular end-diastolic pressure (LVEDP). Cardiac stress biomarkers atrial natriuretic-peptide (ANP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured 1-h post-transfusion. RESULTS: Thirty animals were included (n = 5 per group). Transfusion of RBCs increased LVEDP in a volume-dependent manner (ΔLVEDP [mmHg]: -0.95, +0.50, +6.26, p < 0.001). Fast transfusion increased overall ΔLVEDP by +3.5 mmHg and up to +11.8 mmHg in the four units' group (p = 0.016). Doubling transfusion speed increased ΔLVEDP more than doubling volume in the larger volume groups. No difference in ANP or NT-proBNP were seen in high transfusion volume or groups. CONCLUSION: Transfusion volume dose-dependently increased LVEDP, with speed of transfusion rapidly elevating LVEDP at higher transfusion volumes. ANP and NT-proBNP were not impacted by transfusion volume or speed in this model. TACO is seen as purely volume overload, however, this study emphasizes that limiting transfusion speed, as a modifiable risk factor, might aid in preventing TACO.
Assuntos
Reação Transfusional , Animais , Transfusão de Sangue , Transfusão de Eritrócitos/efeitos adversos , Ratos , Ratos Endogâmicos Lew , Fatores de Risco , Reação Transfusional/etiologiaRESUMO
Lipid accumulation is associated with various forms of acute renal injury; however, the causative factors and pathways underpinning this lipid accumulation have not been thoroughly investigated. In this study, we performed lipidomic profiling of renal tissue following ischaemia-reperfusion injury (IRI). We identified a significant accumulation of cholesterol and specific phospholipids and sphingolipids in kidneys 24 h after IRI. In light of these findings, we hypothesised that pathways involved in lipid metabolism may also be altered. Through the analysis of published microarray data, generated from sham and ischaemic kidneys, we identified nephron-specific metabolic pathways affected by IRI and validated these findings in ischaemic renal tissue. In silico analysis revealed the downregulation of several energy and lipid metabolism pathways, including mitochondrial fatty acid beta-oxidation (FAO), peroxisomal lipid metabolism, fatty acid (FA) metabolism, and glycolysis. The pentose phosphate pathway (PPP), which is fuelled by glycolysis, was the only metabolic pathway that was upregulated 24 h following IRI. In this study, we describe the effect of renal IRI on metabolic pathways and how this contributes to lipid accumulation. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
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Injúria Renal Aguda/metabolismo , Via de Pentose Fosfato/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Patients with interstitial lung diseases (ILDs) frequently present with nondiagnostic high-resolution CT (HRCT) scan and bronchoalveolar lavage (BAL) results, resulting in the need for invasive surgical or cryo-lung biopsy that is associated with significant morbidity. Confocal laser endomicroscopy (CLE) and optical coherence tomography (OCT) are high-resolution laser and light-based techniques that provide real-time imaging of the alveolar compartment during bronchoscopy with a different depth and field of view. OBJECTIVES: The aim of the study was to correlate OCT and CLE imaging to HRCT imaging in ILD. METHODS: This is a retrospective case series of 20 ILD patients who underwent alveolar CLE and OCT imaging during a standard bronchoscopy with BAL, followed by a lung biopsy when indicated. CLE and OCT imaging were compared to four main HRCT patterns and histology. The final diagnosis was based on the multidisciplinary discussion diagnosis. RESULTS: Bronchoscopic CLE and OCT imaging were feasible and safe and provided additional high-detailed anatomical information compared to the HRCT. Bronchoscopic real-time CLE was capable of identification of "alveolar cells" (ground glass opacities) and lung fibrosis (increased alveolar elastin fibers). Bronchoscopic real-time OCT allowed for visualization of "patchy fibrotic disease", "honeycombing" (microcysts), and mucosal granulomas in the airways. CONCLUSIONS: Bronchoscopic CLE and OCT of the alveolar compartment is feasible and safe and enables minimally invasive, high-resolution detection of specific ILD features with the potential to improve ILD diagnostics and monitoring and decrease the need for surgical or cryo-lung biopsies.
Assuntos
Doenças Pulmonares Intersticiais , Humanos , Estudos Retrospectivos , Doenças Pulmonares Intersticiais/diagnóstico , Broncoscopia/métodos , Lavagem Broncoalveolar , Biópsia/métodosRESUMO
Rationale: Bronchial thermoplasty (BT) is a bronchoscopic treatment for severe asthma targeting airway smooth muscle (ASM). Observational studies have shown ASM mass reduction after BT, but appropriate control groups are lacking. Furthermore, as treatment response is variable, identifying optimal candidates for BT treatment is important.Objectives: First, to assess the effect of BT on ASM mass, and second, to identify patient characteristics that correlate with BT response.Methods: Patients with severe asthma (n = 40) were randomized to immediate (n = 20) or delayed (n = 20) BT treatment. Before randomization, clinical, functional, blood, and airway biopsy data were collected. In the delayed control group, reassessment, including biopsies, was performed after 6 months of standard clinical care, followed by BT. In both groups, post-BT data including biopsies were obtained after 6 months. ASM mass (% positive desmin or α-smooth muscle actin area in the total biopsy) was calculated with automated digital analysis software. Associations between baseline characteristics and Asthma Control Questionnaire and Asthma Quality of Life Questionnaire (AQLQ) improvement were explored.Measurements and Main Results: Median ASM mass decreased by >50% in the immediate BT group (n = 17) versus no change in the delayed control group (n = 19) (P = 0.0004). In the immediate group, Asthma Control Questionnaire scores improved with -0.79 (interquartile range [IQR], -1.61 to 0.02) compared with 0.09 (IQR, -0.25 to 1.17) in the delayed group (P = 0.006). AQLQ scores improved with 0.83 (IQR, -0.15 to 1.69) versus -0.02 (IQR, -0.77 to 0.75) (P = 0.04). Treatment response in the total group (n = 35) was positively associated with serum IgE and eosinophils but not with baseline ASM mass.Conclusions: ASM mass significantly decreases after BT when compared with a randomized non-BT-treated control group. Treatment response was associated with serum IgE and eosinophil levels but not with ASM mass.
Assuntos
Asma/cirurgia , Brônquios/cirurgia , Termoplastia Brônquica , Músculo Liso/cirurgia , Adolescente , Adulto , Idoso , Remodelação das Vias Aéreas , Asma/diagnóstico , Asma/patologia , Asma/fisiopatologia , Biópsia , Brônquios/patologia , Broncoscopia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Liso/patologia , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto JovemRESUMO
Diabetic kidney disease (DKD) is among the most common microvascular complications in patients with diabetes, and it currently accounts for the majority of end-stage kidney disease cases worldwide. The pathogenesis of DKD is complex and multifactorial, including systemic and intra-renal inflammatory and coagulation processes. Activated platelets play a pivotal role in inflammation, coagulation, and fibrosis. Mounting evidence shows that platelets play a role in the pathogenesis and progression of DKD. The potentially beneficial effects of antiplatelet agents in preventing progression of DKD has been studied in animal models and clinical trials. This review summarizes the current knowledge on the role of platelets in DKD, including the potential therapeutic effects of antiplatelet therapies.
Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Falência Renal Crônica , Animais , Plaquetas/patologia , Nefropatias Diabéticas/patologia , Inflamação/complicações , Rim/patologia , Falência Renal Crônica/complicaçõesRESUMO
Diabetic nephropathy (DN) is a major complication of diabetes and is associated with high risk for cardiovascular mortality, which is partially related to elevated platelet activity. Platelets are also active players in inflammation and fibrosis. In this study, we examine the effect of ticagrelor-induced platelet inhibition on the development of DN. DN was induced by unilateral nephrectomy followed by streptozotocin injections for 5 days. Mice received ticagrelor (300 mg/kg) or vehicle every other day, for 16 weeks. Experimental groups: non-diabetic control, diabetic control, non-diabetic ticagrelor, and diabetic ticagrelor. Ticagrelor treatment in diabetic mice lowered urinary albumin excretion, it prevented diabetes-induced mesangial matrix expansion, podocyte effacement, and glomerular endothelial cell injury, which includes loss of endothelial fenestrations, ICAM-1 expression, and PECAM expression. In addition, ticagrelor treatment prevented collagen IV deposition and macrophage infiltration in the tubulointerstitium and these diabetic mice showed lower systemic and tubular inflammation and tubular apoptosis. This tubular protection is likely to be a result of protection to the glomerular endothelium by ticagrelor, which reduces albuminuria and albumin toxicity to the tubules and reduced tubular and interstitial inflammation and fibrosis. In conclusion, ticagrelor-induced platelet inhibition protects against renal injury in diabetic mice, likely by protecting the glomerular endothelial cells.
Assuntos
Nefropatias Diabéticas/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Ticagrelor/uso terapêutico , Animais , Apoptose , Colágeno/metabolismo , Nefropatias Diabéticas/etiologia , Células Endoteliais/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/farmacologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Podócitos/efeitos dos fármacos , Ticagrelor/administração & dosagem , Ticagrelor/farmacologiaRESUMO
Introduction: Placental site trophoblastic tumor (PSTT) is a rare subtype of gestational trophoblastic disease. Association of PSTT and nephrotic syndrome is exceedingly rare and has been described in 8 cases thus far. In all cases hysterectomy was performed within months after onset of symptoms, leading to immediate remission of nephrotic syndrome, except for one patient who died of complications of PSTT. Case: We describe the history of a woman in which PSTT was discovered years after onset of nephrotic syndrome. Kidney biopsy revealed lupus-like mesangiocapillary nephritis and over time the patient developed additional symptoms mimicking systemic lupus erythematosus (SLE). Discussion: We provide an overview of the literature on this clinical entity and elaborate on its pathophysiology. In addition, we reflect on the phenomenon of anchoring bias, that led physicians to assume the patient had SLE without questioning this diagnosis in the light of the unexplained finding of increased tumor markers.