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OBJECTIVE: The prevalence of asthma has gradually increased worldwide in recent years, which has made asthma a global public health problem. However, due to its complexity and heterogeneity, there are a few academic debates on the pathogenic mechanism of asthma. The study of the pathogenesis of asthma through metabolomics has become a new research direction. We aim to uncover the metabolic pathway of children with asthma. METHODS: Liquid chromatography (LC)-mass spectrometry (MS)-based metabolomic analysis was conducted to compare urine metabolic profiles between asthmatic children (n = 30) and healthy controls (n = 10). RESULTS: Orthogonal projections to latent structures-discrimination analysis (OPLS-DA) showed that there were significant differences in metabolism between the asthma group and the control group with three different metabolites screened out, including traumatic acid, dodecanedioic acid, and glucobrassicin, and the levels of traumatic acid and dodecanedioic acid in the urine samples of asthmatic children were lower than those of healthy controls therein. Pathway enrichment analysis of differentially abundant metabolites suggested that α-linolenic acid metabolism was an asthma-related pathway. CONCLUSIONS: This study suggests that there are significant metabolic differences in the urine of asthmatic children and healthy controls, and α-linolenic acid metabolic pathways may be involved in the pathogenesis of asthma.
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Transcriptome-wide association study (TWAS) is an important integrative method for identifying genes that are causally associated with phenotypes. A key step of TWAS involves the construction of expression prediction models for every gene in turn using its cis-SNPs as predictors. Different TWAS methods rely on different models for gene expression prediction, and each such model makes a distinct modeling assumption that is often suitable for a particular genetic architecture underlying expression. However, the genetic architectures underlying gene expression vary across genes throughout the transcriptome. Consequently, different TWAS methods may be beneficial in detecting genes with distinct genetic architectures. Here, we develop a new method, HMAT, which aggregates TWAS association evidence obtained across multiple gene expression prediction models by leveraging the harmonic mean P-value combination strategy. Because each expression prediction model is suited to capture a particular genetic architecture, aggregating TWAS associations across prediction models as in HMAT improves accurate expression prediction and enables subsequent powerful TWAS analysis across the transcriptome. A key feature of HMAT is its ability to accommodate the correlations among different TWAS test statistics and produce calibrated P-values after aggregation. Through numerical simulations, we illustrated the advantage of HMAT over commonly used TWAS methods as well as ad hoc P-value combination rules such as Fisher's method. We also applied HMAT to analyze summary statistics of nine common diseases. In the real data applications, HMAT was on average 30.6% more powerful compared to the next best method, detecting many new disease-associated genes that were otherwise not identified by existing TWAS approaches. In conclusion, HMAT represents a flexible and powerful TWAS method that enjoys robust performance across a range of genetic architectures underlying gene expression.
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Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Locos de Características Quantitativas/genética , Transcriptoma/genética , Regulação da Expressão Gênica/genética , Humanos , Modelos Genéticos , Fenótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Carbon monoxide (CO) is an endogenous gasotransmitter produced by the degradation of heme in the presence of heme oxygenase (HO) in mammals. It has been demonstrated that CO participates in a variety of physiological activities and pathological processes, and is closely related to cell protection and homeostasis maintenance in organ tissues. It has been shown by a growing number of studies that CO may play a regulatory and interventional role in the process of the occurrence and development of pain through a variety of mechanisms of action. However, its mechanism of action is still not fully understood and the uncontrollable factors concerning CO administration also placed considerable limitation to its application. This paper reviews the potential targets and pathways of CO in pain regulation and discusses the challenges and opportunities in the clinical application of CO in order to provide suggestions for further exploration and development of CO analgesics.
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Monóxido de Carbono , Heme Oxigenase (Desciclizante) , Animais , Heme Oxigenase-1 , DorRESUMO
Exosomes are typically involved in cellular communication and signaling. Macrophages play a key role in lipopolysaccharide (LPS)-induced sepsis. However, the molecular comparison of exosomes derived from LPS-induced macrophage has not been well analyzed. The macrophage-exosomes are validated and the protein composition of those exosomes are investigated by isobaric tags for relative and absolute quantification (iTRAQ) mass spectrometry. A total of 5056 proteins are identified in macrophage-exosomes. We discovered 341 increased proteins and 363 reduced proteins in LPS-treated macrophage-exosomes compared with control exosomes. In addition, gene ontology analysis demonstrates that macrophage-exosomes proteins are mostly linked to cell, organelle, extracellular region, and membrane. The bioinformatics analysis also indicates that these proteins are mainly involved in cellular process, single-organism process, metabolic process, and biological regulation. Among these 341 upregulated proteins, Kyoto Encyclopedia of Genes and Genomes analysis reveals that 22 proteins are involved in the NOD-like receptor signaling pathway. Finally, hepatocytes can uptake macrophage-exosomes and subsequently NLRP3 inflammasome is activated in vitro and in vivo. These data emphasize the fundamental importance of macrophage-exosomes in sepsis-induced liver injury. Therefore, the iTRAQ proteomic strategy brings new insights into macrophage-derived exosomes. It may improve our understanding of macrophage-exosomes' functions and their possible use as therapeutic targets for sepsis.
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Lesão Pulmonar Aguda/imunologia , Exossomos/imunologia , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Proteínas/imunologia , Lesão Pulmonar Aguda/patologia , Animais , Exossomos/patologia , Hepatócitos/imunologia , Hepatócitos/patologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas/análise , Proteômica , Células RAW 264.7RESUMO
Arecoline induces oral submucous fibrosis (OSF) via promoting the reactive oxygen species (ROS). Angiotensin (1-7) (Ang-(1-7)) protects against fibrosis by counteracting angiotensin II (Ang-II) via the Mas receptor. However, the effects of Ang-(1-7) on OSF remain unknown. NOD-like receptors (NLRs) family pyrin domain containing 3 (NLRP3) inflammasome is identified as the novel mechanism of fibrosis. Whereas the effects of arecoline on NLRP3 inflammasome remain unclear. We aimed to explore the effect of Ang-(1-7) on NLRP3 inflammasome in human oral myofibroblasts. In vivo, activation of NLRP3 inflammasomes with an increase of Ang-II type 1 receptor (AT1R) protein level and ROS production in human oral fibrosis tissues. Ang-(1-7) improved arecoline-induced rats OSF, reduced protein levels of NADPH oxidase 4 (NOX4) and the NLRP3 inflammasome. In vitro, arecoline increased ROS along with upregulation of the angiotensin-converting enzyme (ACE)/Ang-II/AT1R axis and NLRP3 inflammasome/interleukin-1ß axis in human oral myofibroblasts, which were reduced by NOX4 inhibitor VAS2870, ROS scavenger N-acetylcysteine, and NOX4 small interfering RNA (siRNA). Furthermore, arecoline induced collagen synthesis or migration via the Smad or RhoA-ROCK pathway respectively, which could be inhibited by NLRP3 siRNA or caspase-1 blocker VX-765. Ang-(1-7) shifted the balance of RAS toward the ACE2/Ang-(1-7)/Mas axis, inhibited arecoline-induced ROS and NLRP3 inflammasome activation, leading to attenuation of migration or collagen synthesis. In summary, Ang-(1-7) attenuates arecoline-induced migration and collagen synthesis via inhibiting NLRP3 inflammasome in human oral myofibroblasts.
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Angiotensina I/farmacologia , Anti-Inflamatórios/farmacologia , Arecolina/toxicidade , Movimento Celular/efeitos dos fármacos , Colágeno/biossíntese , Miofibroblastos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/agonistas , Fibrose Oral Submucosa/prevenção & controle , Fragmentos de Peptídeos/farmacologia , Enzima de Conversão de Angiotensina 2 , Animais , Antioxidantes/farmacologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Miofibroblastos/metabolismo , Miofibroblastos/patologia , NADPH Oxidase 4/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fibrose Oral Submucosa/induzido quimicamente , Fibrose Oral Submucosa/metabolismo , Fibrose Oral Submucosa/patologia , Peptidil Dipeptidase A/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/metabolismo , Piroptose/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Epidemiological studies demonstrated that adverse in utero environment was associated with increased risk of offspring high blood pressure, by using birthweight as the proxy of maternal intrauterine exposure; however, the nature of such association remains less understood. METHODS: With maternal/fetal-specific summary statistics of birthweight (n = 297â356 for own birthweight and n = 210â248 for offspring birthweight) and summary statistics of blood pressure [i.e. systolic blood pressure (SBP), diastolic blood pressure (DBP) and pulse pressure (PP)] (n = 757â601), we evaluated the genetic correlation between fetal-specific birthweight and blood pressure using cross-trait linkage disequilibrium score regression, and next detected pleiotropic genes for them with a pleiotropy mapping method called mixture-adjusted intersect-union pleiotropy test. Furthermore, we conducted a genetic risk score (GRS)-based Mendelian randomization analysis in parent-offspring pairs (n = 6031) of the UK Biobank cohort, to assess the causal relation between maternal-specific GRS and blood pressure conditioning on fetal genotypes. RESULTS: We found fetal-specific birthweight had a negative genetic correlation with DBP (ρ^g = -0.174, P = 1.68 × 10-10), SBP (ρ^g = -0.198, P = 8.09 × 10-12), and PP (ρ^g = -0.152, P = 6.04 × 10-8), and detected 143, 137 and 135 pleiotropic genes shared between fetal-specific birthweight and PP, SBP and DBP, respectively. These genes often exhibited opposite genetic effects, and were more likely to be differentially expressed in pancreas, liver, heart, brain, whole blood and muscle skeletal tissues. A causal negative association of maternal-specific birthweight was identified with SBP (P = 2.20 × 10-2) and PP (P = 7.67 × 10-3) but not DBP (P = 0.396) in mother-offspring pairs, after accounting for the influence of fetal-specific GRS; and the two significant relations were robust against the horizontal pleiotropy of instruments and the confounding influence of gestational duration and preterm birth. However, these causal associations could not be detected in father-offspring pairs. CONCLUSIONS: This study revealed common genetic components underlying birthweight and blood pressure, and provided important insight into aetiology and early prevention of high blood pressure.
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Hipertensão , Nascimento Prematuro , Feminino , Recém-Nascido , Humanos , Peso ao Nascer/genética , Pressão Sanguínea/genética , Análise da Randomização Mendeliana , Fatores de Risco , Estudo de Associação Genômica AmplaRESUMO
We present an efficient and easy synthesis method for incorporating organocatalytic moieties into Zr-metal organic frameworks (Zr-MOFs). The catalytic activity and selectivity of the new chiral catalysts were improved by adjusting the aperture of the MOF cavities. The hole size of the Zr-MOF was modulated by adding acid and replacing bridge ligands during synthesis. The difunctional chiral units of amino acid-thiourea are anchored onto the Zr-MOF by a mild synthesis method from an isothiocyanate intermediate which could effectively avoid the racemization of chiral moieties in the synthesis process. By means of specific surface area measurement (BET), scanning electron microscopy (SEM) and powder X-ray Diffraction (PXRD), it was confirmed that Zr-MOFs with different pore sizes were synthesized without breaking the basic octahedral structure of the MOF. Finally, good yields (up to 83%) and ee values (up to 73%) were achieved with the new heterogeneous catalysts in 48 hours for the aldol reaction of 4-nitrobenzaldehyde with acetone. By contrast, using the catalyst support without modulating the synthesis, the yield (30%) and the ee-value (26%) were both low. Experiments have confirmed the important influence on the reaction selectivity of providing a suitable reaction environment by controlling the aperture of MOF cavities.
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BACKGROUND: Macrophages are involved in the pathogenesis of idiopathic pulmonary fibrosis, partially by activating lung fibroblasts. However, how macrophages communicate with lung fibroblasts is largely unexplored. Exosomes can mediate intercellular communication, whereas its role in lung fibrogenesis is unclear. Here we aim to investigate whether exosomes can mediate the crosstalk between macrophages and lung fibroblasts and subsequently induce fibrosis. METHODS: In vivo, bleomycin (BLM)-induced lung fibrosis model was established and macrophages infiltration was examined. The effects of GW4869, an exosomes inhibitor, on lung fibrosis were assessed. Moreover, macrophage exosomes were injected into mice to observe its pro-fibrotic effects. In vitro, exosomes derived from angiotensin II (Ang II)-stimulated macrophages were collected. Then, lung fibroblasts were treated with the exosomes. Twenty-four hours later, protein levels of α-collagen I, angiotensin II type 1 receptor (AT1R), transforming growth factor-ß (TGF-ß), and phospho-Smad2/3 (p-Smad2/3) in lung fibroblasts were examined. The Student's t test or analysis of variance were used for statistical analysis. RESULTS: In vivo, BLM-treated mice showed enhanced infiltration of macrophages, increased fibrotic alterations, and higher levels of Ang II and AT1R. GW4869 attenuated BLM-induced pulmonary fibrosis. Mice with exosomes injection showed fibrotic features with higher levels of Ang II and AT1R, which was reversed by irbesartan. In vitro, we found that macrophages secreted a great number of exosomes. The exosomes were taken by fibroblasts and resulted in higher levels of AT1R (0.22â±â0.02 vs. 0.07â±â0.02, tâ=â8.66, Pâ=â0.001), TGF-ß (0.54â±â0.05 vs. 0.09â±â0.06, tâ=â10.00, Pâ<â0.001), p-Smad2/3 (0.58â±â0.06 vs. 0.07â±â0.03, tâ=â12.86, Pâ<â0.001) and α-collagen I (0.27â±â0.02 vs. 0.16â±â0.01, tâ=â7.01, Pâ=â0.002), and increased Ang II secretion (62.27â±â7.32 vs. 9.56â±â1.68, tâ=â12.16, Pâ<â0.001). Interestingly, Ang II increased the number of macrophage exosomes, and the protein levels of Alix (1.45â±â0.15 vs. 1.00â±â0.10, tâ=â4.32, Pâ=â0.012), AT1R (4.05â±â0.64 vs. 1.00â±â0.09, tâ=â8.17, Pâ=â0.001), and glyceraldehyde-3-phosphate dehydrogenase (2.13â±â0.36 vs. 1.00â±â0.10, tâ=â5.28, Pâ=â0.006) were increased in exosomes secreted by the same number of macrophages, indicating a positive loop between Ang II and exosomes production. CONCLUSIONS: Exosomes mediate intercellular communication between macrophages and fibroblasts plays an important role in BLM-induced pulmonary fibrosis.
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Exossomos , Fibrose Pulmonar , Angiotensina II , Animais , Bleomicina/toxicidade , Fibroblastos , Pulmão , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Receptor Tipo 1 de AngiotensinaRESUMO
Extracellular vesicles (EVs) have emerged as important vectors of intercellular dialogue. High mobility group box protein 1 (HMGB1) is a typical damage-associated molecular pattern (DAMP) molecule, which is cytotoxic and leads to cell death and tissue injury. Whether EVs are involved in the release of HMGB1 in lipopolysaccharide (LPS)-induced acute liver injuries need more investigation. EVs were identified by transmission electron microscopy, nanoparticle tracking analysis (NTA), and western blotting. The co-localization of HMGB1, RAGE (receptor for advanced glycation end-products), EEA1, Rab5, Rab7, Lamp1 and transferrin were detected by confocal microscopy. The interaction of HMGB1 and RAGE were investigated by co-immunoprecipitation. EVs were labeled with the PKH67 and used for uptake experiments. The pyroptotic cell death was determined by FLICA 660-YVAD-FMK. The expression of NLRP3 (NOD-like receptor family pyrin domain containing 3) inflammasomes were analyzed by western-blot or immunohistochemistry. Serum HMGB1, ALT (alanine aminotransferase), AST (aspartate aminotransferase), LDH (lactate dehydrogenase) and MPO (myeloperoxidase) were measured using a commercial kit. The extracellular vesicle HMGB1 was detected in the serums of sepsis patients. Macrophages were found to contribute to HMGB1 release through the EVs. HMGB1-RAGE interactions participated in the loading of HMGB1 into the EVs. These EVs shuttled HMGB1 to target cells by transferrin-mediated endocytosis leading to hepatocyte pyroptosis by the activation of NLRP3 inflammasomes. Moreover, a positive correlation was verified between the sepsis serum EVs-HMGB1 level and clinical liver damage. This finding provides insights for the development of novel diagnostic and therapeutic strategies for acute liver injuries.
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Genome-wide association studies (GWAS) have identified multiple causal genes associated with amyotrophic lateral sclerosis (ALS); however, the genetic architecture of ALS remains completely unknown and a large number of causal genes have yet been discovered. To full such gap in part, we implemented an integrative analysis of transcriptome-wide association study (TWAS) for ALS to prioritize causal genes with summary statistics from 80,610 European individuals and employed 13 GTEx brain tissues as reference transcriptome panels. The summary-level TWAS analysis with single brain tissue was first undertaken and then a flexible p-value combination strategy, called summary data-based Cauchy Aggregation TWAS (SCAT), was proposed to pool association signals from single-tissue TWAS analysis while protecting against highly positive correlation among tests. Extensive simulations demonstrated SCAT can produce well-calibrated p-value for the control of type I error and was often much more powerful to identify association signals across various scenarios compared with single-tissue TWAS analysis. Using SCAT, we replicated three ALS-associated genes (i.e., ATXN3, SCFD1, and C9orf72) identified in previous GWASs and discovered additional five genes (i.e., SLC9A8, FAM66D, TRIP11, JUP, and RP11-529H20.6) which were not reported before. Furthermore, we discovered the five associations were largely driven by genes themselves and thus might be new genes which were likely related to the risk of ALS. However, further investigations are warranted to verify these results and untangle the pathophysiological function of the genes in developing ALS.
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PURPOSE: To evaluate the technical efficacy and safety of the pull-through technique in recanalization of transjugular intrahepatic portosystemic shunt (TIPS) when standard transjugular approach is inaccessible. MATERIALS AND METHODS: A retrospective review of patients underwent TIPS revision via the pull-through technique was performed. Transhepatic directly punctured stent was conducted if the portal vein could not be accessed via standard transjugular approach. Technical success was defined by recanalization of shunt. Clinical success was defined as bleeding interruption and ascites regression without pharmacological support. All patients were followed up by clinical evaluation and Doppler ultrasound. RESULTS: Between January 2010 and December 2016, a total of 63 patients underwent TIPS revision, and 14 of them could not be accessed via standard transjugular approaches owing to stenosis or occlusion of the hepatic vein. The pull-through technique was successful in 13 patients, and one patient underwent parallel TIPS. No procedure-related complication was observed. One patient died of liver failure one week after the procedure. During the follow-up, three patients developed hepatic encephalopathy, and one patient developed TIPS dysfunction again and experienced variceal bleeding. The primary patency rate after TIPS revision was 92% (11/12) at 12 months. CONCLUSION: The pull-through technique was effective and safe for recanalization of TIPS inaccessible via standard transjugular approach.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Human beings are increasingly exposed to phthalates, which are a group of chemicals used to make plastics more flexible and harder to break, and simultaneously ingesting abundant food emulsifiers via daily diet. The purpose of this study was to investigate the effect of the food emulsifier glycerin monostearate (GMS) on male reproductive toxicity caused by di(2-ethylhexyl) phthalate (DEHP, one of the phthalates) and explore the underlying mechanism. Thirty male Sprague-Dawley rats were randomly divided into control group, DEHP group and DEHP+GMS group. Rats in the DEHP group and DEHP+GMS group were orally administered with 200 mg/kg/d DEHP with or without 20 mg/kg/d GMS. After 30 days of continuous intervention, it was found that the serum testosterone level was significantly lowered in DEHP group and DEHP+GMS group than that in control group (P<0.01). The serum testosterone level and the relative testis weight were significantly decreased in the DEHP+GMS group as compared with those in the DEHP group and control group (P<0.05). More spermatids were observed to be shed off in DEHP+GMS group than in DEHP group. The expression levels of cell cycle checkpoint kinase 1 (Chk1), cell division cycle gene 2 (Cdc2), and cyclin-dependent kinase 2 (CDK2) were down-regulated in DEHP group, and this tendency was more significant in DEHP+GMS group (P<0.05 or P<0.01). There was no significant difference in the P-glycoprotein (P-gp) expression between DEHP group and control group. However, P-gp was markedly down-regulated in DEHP+GMS group (P<0.01). The results indicated that the food emulsifier GMS aggravated the toxicity of DEHP on male reproduction by inhibiting the cell cycle of testicular cells and the expression of P-gp in testis tissues.
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Dietilexilftalato/toxicidade , Emulsificantes/toxicidade , Glicerol/toxicidade , Reprodução/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Animais , Proteína Quinase CDC2/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Dietilexilftalato/administração & dosagem , Regulação para Baixo , Emulsificantes/administração & dosagem , Glicerol/administração & dosagem , Masculino , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testosterona/sangueRESUMO
The Lidanpaidu Prescription (LDP), a hospital preparation, composed of Chinese classical preparations, has been reported to have antiendotoxin, anticoagulant and other effects. However, its therapeutic effect on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) and the mechanisms remain unclear. Therefore, we administered LPD pretreatment at different doses to examine the protective effects and mechanisms in LPS-induced AKI in mice. The kidney injury induced by LPS was assessed by histological examination. ELISA was used to detect the levels of inflammatory cytokines. The mRNA expression of the inflammatory genes IKKß and TNF-α in kidney tissues was assessed by RT-PCR. Finally, Western blot was performed to assess the NF-κB signaling pathway related proteins, and the nuclear translocation of NF-kB P65 was detected by immunofluorescence laser confocal microscopy. The findings suggested that LDP significantly improved at 48â¯h animal survival (66.7%), compared with the LPS group (26.7%), determined by a Kaplan-Meier analysis. LDP attenuated the kidney histopathological changes induced by LPS and decreased the inflammatory cytokine levels in serum and renal tissue. Moreover, LDP markedly inhibited the expression of inflammatory genes and suppressed the activation of relevant proteins in the nucleus. In summary, these findings suggest that LDP reduces LPS-induced AKI via a mechanism related to the suppression of the NF-κB signaling pathway.
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Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , NF-kappa B/metabolismo , Transdução de Sinais , Injúria Renal Aguda/sangue , Injúria Renal Aguda/induzido quimicamente , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Camundongos Endogâmicos BALB C , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sepse/sangue , Sepse/complicações , Sepse/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Análise de Sobrevida , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Autophagy, interacting with actin cytoskeleton and the NO-dependent pathway, may affect the phenotype and function of endothelial cells. Moreover, caveolin-1 (Cav-1), as a structure protein in liver sinusoidal endothelial cells (LSECs), is closely related to autophagy. Hence, we aim to explore the role of autophagic degradation of Cav-1 in LSECs defenestration. In vivo, we found the increase of autophagy in liver sinusoidal endothelium in human fibrotic liver. Furthermore, autophagy, degradation of Cav-1, and actin filament (F-actin) remodeling were triggered during the process of CCl4-induced LSECs defenestration; in contrast, autophagy inhibitor 3MA diminished the degradation of Cav-1 to maintain fenestrae and relieve CCl4-induced fibrosis. In vitro, during LSECs defenestration, the NO-dependent pathway was down-regulated through the reduction of the PI3K-AKT-MTOR pathway and initiation of autophagic degradation of Cav-1; while, these effects were aggravated by starvation. However, VEGF inhibited autophagic degradation of Cav-1 and F-actin remodeling to maintain LSECs fenestrae via activating the PI3K-AKT-MTOR pathway. Additionally, inhibiting autophagy, such as 3MA, bafilomycin, or ATG5-siRNA, could attenuate the depletion of Cav-1 and F-actin remodeling to maintain LSECs fenestrae and improve the NO-dependent pathway; in turn, eNOS-siRNA and L-NAME, for blocking the NO-dependent pathway, could elevate autophagic degradation of Cav-1 to aggravate defenestration. Finally, overexpressed Cav-1 rescued rapamycin-induced autophagic degradation of Cav-1 to maintain LSECs fenestrae; whereas knockdown of Cav-1 facilitated defenestration due to the activation of the AMPK-dependent autophagy. Consequently, autophagic degradation of Cav-1 promotes LSECs defenestration via inhibiting the NO-dependent pathway and F-actin remodeling.
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Autofagia , Caveolina 1/metabolismo , Células Endoteliais/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Proteólise , Animais , Tetracloreto de Carbono/toxicidade , Intoxicação por Tetracloreto de Carbono/metabolismo , Intoxicação por Tetracloreto de Carbono/patologia , Células Endoteliais/patologia , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Aldosterone, with pro-oxidation and pro-autophagy capabilities, plays a key role in liver fibrosis. However, the mechanisms underlying aldosterone-promoted liver sinusoidal endothelial cells (LSECs) defenestration remain unknown. Caveolin 1 (Cav1) displays close links with autophagy and fenestration. Hence, we aim to investigate the role of Cav1-related autophagy in LSECs defenestration. We found the increase of aldosterone/MR (mineralocorticoid receptor) level, oxidation, autophagy, and defenestration in LSECs in the human fibrotic liver, BDL or hyperaldosteronism models; while antagonizing aldosterone or inhibiting autophagy relieved LSECs defenestration in BDL-induced fibrosis or hyperaldosteronism models. In vitro, fenestrae of primary LSECs gradually shrank, along with the down-regulation of the NO-dependent pathway and the augment of the AMPK-dependent autophagy; these effects were aggravated by rapamycin (an autophagy activator) or aldosterone treatment. Additionally, aldosterone increased oxidation mediated by Cav1, reduced ATP generation, and subsequently induced the AMPK-dependent autophagy, leading to the down-regulation of the NO-dependent pathway and LSECs defenestration. These effects were reversed by MR antagonist spironolactone, antioxidants or autophagy inhibitors. Besides, aldosterone enhanced the co-immunoprecipitation of Cav1 with p62 and ubiquitin, and induced Cav1 co-immunofluorescence staining with LC3, ubiquitin, and F-actin in the perinuclear area of LSECs. Furthermore, aldosterone treatment increased the membrane protein level of Cav1, whereas decrease the cytoplasmic protein level of Cav1, indicating that aldosterone induced Cav1-related selective autophagy and F-actin remodeling to promote defenestration. Consequently, Cav1-related selective autophagy initiated by aldosterone-induced oxidation promotes LSECs defenestration via activating the AMPK-ULK1 pathway and inhibiting the NO-dependent pathway.
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Aldosterona/farmacologia , Autofagia , Caveolina 1/metabolismo , Células Endoteliais/metabolismo , Cirrose Hepática/metabolismo , Estresse Oxidativo , Quinases Proteína-Quinases Ativadas por AMP , Actinas/metabolismo , Animais , Capilares/citologia , Capilares/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Humanos , Fígado/irrigação sanguínea , Fígado/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Ubiquitina/metabolismoRESUMO
AIMS: Angiotensin II (AngII), a vasoconstrictive peptide of the renin-angiotensin system (RAS), promotes hepatic fibrogenesis and induces microRNA-21(mir-21) expression. Angiotensin-(1-7) [Ang-(1-7)] is a peptide of the RAS, which attenuates liver fibrosis. Recently, it was reported that the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome participated in liver fibrosis. However, it remains unclear how mir-21 mediates AngII-induced NLRP3 inflammasome activation. We investigate the role of AngII-induced mir-21 in the regulation of NLRP3 inflammasome/IL-1ß axis in liver fibrosis. RESULTS: In vivo, circulating mir-21 was upregulated in patients with liver fibrosis and was positively correlated with liver fibrosis and oxidation. Treatment with Ang-(1-7) inhibited mir-21, NLRP3 inflammasome, and liver fibrosis after bile duct ligation (BDL) or AngII infusion. Inhibition of mir-21 suppressed the Smad7/Smad2/3/NOX4, Spry1/ERK/NF-κB pathway, NLRP3 inflammasome, and liver fibrosis induced by AngII infusion. In vitro, AngII upregulated mir-21 expression via targeting Smad7 and Spry1 in primary hepatic stellate cells (HSCs). In contrast, Ang-(1-7) suppressed mir-21 expression and oxidation induced by AngII. Overexpression of mir-21 promoted oxidation, and collagen production enhanced the effect of AngII on NLRP3 inflammasome activation via the Spry1/ERK/NF-κB, Smad7/Smad2/3/NOX4 pathways. However, downregulation of mir-21 exerted the opposite effects. Innovation and Conclusions: Mir-21 mediates AngII-activated NLRP3 inflammasome and resultant HSC activation via targeting Spry1 and Smad7. Ang-(1-7) protected against BDL or AngII infusion-induced hepatic fibrosis and inhibited mir-21 expression. Antioxid. Redox Signal. 27, 1-20.
Assuntos
Angiotensina II/farmacologia , Inflamassomos/metabolismo , Cirrose Hepática/genética , MicroRNAs/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Interleucina-1beta/metabolismo , Cirrose Hepática/metabolismo , Proteínas de Membrana , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fosfoproteínas , Ratos , Proteína Smad7/metabolismoRESUMO
OBJECTIVE: To investigate the effect of angiotension II (AngII) on the activation of NLRP3 inflammasome and the expression of interleukin-1ß (IL-1ß) in human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs cultured in vitro were treated with different concentrations of AngII for varying lengths of time to determine the optimal concentration and time for AngII exposure. To test the impact of different agents on the effect of AngII exposure, HUVECs were pretreated with AngII receptor blocker losartan, NAD(P)H inhibitor DPI and H(2)O(2) scavenger CAT, caspase 1 inhibitor YVAD, or NLRP3 siRNA for silencing NLRP3, and the protein levels of NOX4, NLRP3, caspase-1 and IL-1ß in HUVECs were analyzed by Western blotting. RESULTS: AngII treatment at the optimal concentration (10(-9) mol/L) for 12 h significantly increased the protein levels of NOX4, NLRP3, caspase1 and IL-1ß in HUVECs. Pretreatment with losartan, DPI, CAT, YVAD, or NLRP3 siRNA all attenuated the effects of AngII on the cells. CONCLUSION: AngII can induce vascular inflammation by promoting the production of reactive oxygen species and activating NLRP3 inflammasome to increase the protein expression of IL-1ß in HUVECs.
Assuntos
Angiotensina II/farmacologia , Proteínas de Transporte/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/farmacologia , Western Blotting , Caspase 1/metabolismo , Humanos , Peróxido de Hidrogênio , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismoRESUMO
Epithelial-mesenchymal transition (EMT) is correlated with NAPDH oxidase (NOX)-derived reactive oxygen species (ROS). The ROS-induced NOD-like receptor pyrin domain containing-3 (NLRP3) inflammasome is a novel mechanism of EMT. Angiotensin II (AngII) induces EMT by regulating intracellular ROS. Nevertheless, it has not been reported whether AngII could induce hepatocyte EMT. Angiotensin-(1-7) [Ang-(1-7)] can inhibit the effects of AngII via a counter-regulatory mechanism. However, whether Ang-(1-7) attenuated the effects of AngII on hepatocyte EMT remains unclear. The aim of this study was to determine whether Ang-(1-7) attenuated AngII-induced hepatocyte EMT by inhibiting the NOX-derived ROS-mediated NLRP3 inflammasome/IL-1ß/Smad circuit. In vivo, two animal models were established. In the first model, rats were infused AngII. In the second model, Ang-(1-7) was constantly infused into double bile duct ligated (BDL) rats. In vitro, hepatocytes were pretreated with antioxidant, NLRP3 siRNA, NOX4 siRNA, or Ang-(1-7) before exposure to AngII. In vitro, AngII induced hepatocyte EMT, which was inhibited by N-acetylcysteine (NAC), diphenylene iodonium (DPI), and NOX4 siRNA. NLRP3 inflammasome, which was activated by hydrogen peroxide (H2O2), mediated AngII-induced hepatocyte EMT. Ang-(1-7) suppressed AngII-induced EMT by inhibiting the NOX-derived H2O2-activated NLRP3 inflammasome/IL-1ß/Smad circuit. In vivo, infusion of AngII induced activation of H2O2-correlated NLRP3 inflammasome in rat livers and accumulation of α-collagen I (Col1A1) in hepatocytes. Infusion of Ang-(1-7) alleviated BDL-induced liver fibrosis and inhibited the expression of Col1A1 and the activation of NLRP3 inflammasome in hepatocytes. Ang-(1-7) attenuated AngII-induced hepatocyte EMT by inhibiting the NOX-derived H2O2-activated NLRP3 inflammasome/IL-1ß/Smad circuit.