RESUMO
BACKGROUND AIMS: Prolonged systemic inflammation contributes to poor clinical outcomes in severe alcohol-associated hepatitis (AH) even after the cessation of alcohol use. However, mechanisms leading to this persistent inflammation remain to be understood. APPROACH RESULTS: We show that while chronic alcohol induces nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome activation in the liver, alcohol binge results not only in NLRP3 inflammasome activation but also in increased circulating extracellular apoptosis-associated speck-like protein containing a caspase recruitment domain (ex-ASC) specks and hepatic ASC aggregates both in patients with AH and in mouse models of AH. These ex-ASC specks persist in circulation even after the cessation of alcohol use. Administration of alcohol-induced-ex-ASC specks in vivo in alcohol-naive mice results in sustained inflammation in the liver and circulation and causes liver damage. Consistent with the key role of ex-ASC specks in mediating liver injury and inflammation, alcohol binge failed to induce liver damage or IL-1ß release in ASC-deficient mice. Our data show that alcohol induces ex-ASC specks in liver macrophages and hepatocytes, and these ex-ASC specks can trigger IL-1ß release in alcohol-naive monocytes, a process that can be prevented by the NLRP3 inhibitor, MCC950. In vivo administration of MCC950 reduced hepatic and ex-ASC specks, caspase-1 activation, IL-1ß production, and steatohepatitis in a murine model of AH. CONCLUSIONS: Our study demonstrates the central role of NLRP3 and ASC in alcohol-induced liver inflammation and unravels the critical role of ex-ASC specks in the propagation of systemic and liver inflammation in AH. Our data also identify NLRP3 as a potential therapeutic target in AH.
Assuntos
Hepatite Alcoólica , Hepatite , Animais , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatite/etiologia , Inflamação , Hepatite Alcoólica/etiologia , Etanol/efeitos adversos , Caspase 1/metabolismo , Interleucina-1beta/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismoRESUMO
BACKGROUND AND OBJECTIVES: Patient monitoring systems provide critical information but often produce loud, frequent alarms that worsen patient agitation and stress. This may increase the use of physical and chemical restraints with implications for patient morbidity and autonomy. This study analyzes how augmenting alarm thresholds affects the proportion of alarm-free time and the frequency of medications administered to treat acute agitation. METHODS: Our emergency department's patient monitoring system was modified on June 28, 2022 to increase the tachycardia alarm threshold from 130 to 150 and to remove alarm sounds for several arrhythmias, including bigeminy and premature ventricular beats. A pre-post study was performed lasting 55 days before and 55 days after this intervention. The primary outcome was change in number of daily patient alarms. The secondary outcomes were alarm-free time per day and median number of antipsychotic and benzodiazepine medications administered per day. The safety outcome was the median number of patients transferred daily to the resuscitation area. We used quantile regression to compare outcomes between the pre- and post-intervention period and linear regression to correlate alarm-free time with the number of sedating medications administered. RESULTS: Between the pre- and post-intervention period, the median number of alarms per day decreased from 1332 to 845 (-37%). This was primarily driven by reduced low-priority arrhythmia alarms from 262 to 21 (-92%), while the median daily census was unchanged (33 vs 32). Median hours per day free from alarms increased from 1.0 to 2.4 (difference 1.4, 95% CI 0.8-2.1). The median number of sedating medications administered per day decreased from 14 to 10 (difference - 4, 95% CI -1 to -7) while the number of escalations in level of care to our resuscitation care area did not change significantly. Multivariable linear regression showed a 60-min increase of alarm-free time per day was associated with 0.8 (95% CI 0.1-1.4) fewer administrations of sedating medication while an additional patient on the behavioral health census was associated with 0.5 (95% CI 0.0-1.1) more administrations of sedating medication. CONCLUSION: A reasonable change in alarm parameter settings may increase the time patients and healthcare workers spend in the emergency department without alarm noise, which in this study was associated with fewer doses of sedating medications administered.
Assuntos
Alarmes Clínicos , Serviço Hospitalar de Emergência , Agitação Psicomotora , Humanos , Masculino , Agitação Psicomotora/tratamento farmacológico , Feminino , Pessoa de Meia-Idade , Antipsicóticos/uso terapêutico , Antipsicóticos/administração & dosagem , Adulto , Idoso , Benzodiazepinas/uso terapêutico , Benzodiazepinas/administração & dosagem , Monitorização Fisiológica/métodos , Hipnóticos e Sedativos/uso terapêutico , Hipnóticos e Sedativos/administração & dosagemRESUMO
Dr. Patrick Lowe: Our case today is that of a 47-year-old woman who was referred to our emergency department (ED) due to bloody urine, dark tarry stools, red spots on her skin, and bruising throughout her body. Fourteen days prior to presentation, she began exhibiting intermittent fevers, headache, shortness of breath, and a dry cough, and she tested positive for SARS-CoV-2 (the virus that causes COVID-19 pneumonia). Over the 3 days prior to her ED presentation, she experienced a headache that was more intense than the headaches she had been having in the preceding 2 weeks. She reported episodes of both dark urine as well as bright red blood in her urine. In addition, she had multiple dark stools described as tar-like when asked. On the day of her ED presentation, the patient noted a red rash throughout her body. In addition, earlier in the day, she had atraumatic self-limited epistaxis. She denied any falls or head strikes, vision changes, focal weakness or numbness, shortness of breath, chest pain, abdominal pain, or peripheral swelling.
Assuntos
COVID-19 , COVID-19/complicações , Tosse , Dispneia/etiologia , Feminino , Cefaleia , Humanos , Pessoa de Meia-Idade , SARS-CoV-2RESUMO
BACKGROUND: Chronic alcohol consumption is associated with neuroinflammation, neuronal damage, and behavioral alterations including addiction. Alcohol-induced neuroinflammation is characterized by increased expression of proinflammatory cytokines (including TNFα, IL-1ß, and CCL2) and microglial activation. We hypothesized chronic alcohol consumption results in peripheral immune cell infiltration to the CNS. Since chemotaxis through the CCL2-CCR2 signaling axis is critical for macrophage recruitment peripherally and centrally, we further hypothesized that blockade of CCL2 signaling using the dual CCR2/5 inhibitor cenicriviroc (CVC) would prevent alcohol-induced CNS infiltration of peripheral macrophages and alter the neuroinflammatory state in the brain after chronic alcohol consumption. METHODS: C57BL/6J female mice were fed an isocaloric or 5% (v/v) ethanol Lieber DeCarli diet for 6 weeks. Some mice received daily injections of CVC. Microglia and infiltrating macrophages were characterized and quantified by flow cytometry and visualized using CX3CR1eGFP/+ CCR2RFP/+ reporter mice. The effect of ethanol and CVC treatment on the expression of inflammatory genes was evaluated in various regions of the brain, using a Nanostring nCounter inflammation panel. Microglia activation was analyzed by immunofluorescence. CVC-treated and untreated mice were presented with the two-bottle choice test. RESULTS: Chronic alcohol consumption induced microglia activation and peripheral macrophage infiltration in the CNS, particularly in the hippocampus. Treatment with CVC abrogated ethanol-induced recruitment of peripheral macrophages and partially reversed microglia activation. Furthermore, the expression of proinflammatory markers was upregulated by chronic alcohol consumption in various regions of the brain, including the cortex, hippocampus, and cerebellum. Inhibition of CCR2/5 decreased alcohol-mediated expression of inflammatory markers. Finally, microglia function was impaired by chronic alcohol consumption and restored by CVC treatment. CVC treatment did not change the ethanol consumption or preference of mice in the two-bottle choice test. CONCLUSIONS: Together, our data establish that chronic alcohol consumption promotes the recruitment of peripheral macrophages into the CNS and microglia alterations through the CCR2/5 axis. Therefore, further exploration of the CCR2/5 axis as a modulator of neuroinflammation may offer a potential therapeutic approach for the treatment of alcohol-associated neuroinflammation.
Assuntos
Encéfalo/metabolismo , Etanol/toxicidade , Macrófagos/metabolismo , Microglia/metabolismo , Receptores CCR2/metabolismo , Receptores CCR5/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Antagonistas dos Receptores CCR5/farmacologia , Etanol/administração & dosagem , Feminino , Imidazóis/farmacologia , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Receptores CCR2/antagonistas & inibidores , Sulfóxidos/farmacologiaRESUMO
Cellular homeostais, that is normally maintained through autophagy, is disrupted in alcoholic liver disease (ALD). Because autophagy and exosome biogenesis share common elements, we hypothesized that increased exosome production in ALD may be linked to disruption of autophagic function. We found impaired autophagy both in ALD and alcoholic hepatitis (AH) mouse models and human livers with ALD as indicated by increased hepatic p62 and LC3-II levels. Alcohol reduced autophagy flux in vivo in chloroquine-treated mice as well as in vitro in hepatocytes and macrophages treated with bafilomycin A. Our results revealed that alcohol targets multiple steps in the autophagy pathway. Alcohol-related decrease in mechanistic target of rapamycin (mTOR) and Ras homolog enriched in brain (Rheb), that initiate autophagy, correlated with increased Beclin1 and autophagy-related protein 7 (Atg7), proteins involved in phagophore-autophagosome formation, in ALD. We found that alcohol disrupted autophagy function at the lysosomal level through decreased lysosomal-associated membrane protein 1 (LAMP1) and lysosomal-associated membrane protein 2 (LAMP2) in livers with ALD. We identified that micro-RNA 155 (miR-155), that is increased by alcohol, targets mTOR, Rheb, LAMP1, and LAMP2 in the authophagy pathway. Consistent with this, miR-155-deficient mice were protected from alcohol-induced disruption of autophagy and showed attenuated exosome production. Mechanistically, down-regulation of LAMP1 or LAMP2 increased exosome release in hepatocytes and macrophages in the presence and absence of alcohol. These results suggested that the alcohol-induced increase in exosome production was linked to disruption of autophagy and impaired autophagosome and lysosome function. Conclusion: Alcohol affects multiple genes in the autophagy pathway and impairs autophagic flux at the lysosome level in ALD. Inhibition of LAMP1 and LAMP2 promotes exosome release in ALD. We identified miR-155 as a mediator of alcohol-related regulation of autophagy and exosome production in hepatocytes and macrophages.
Assuntos
Autofagia/fisiologia , Exossomos/fisiologia , Hepatopatias Alcoólicas/fisiopatologia , Lisossomos/fisiologia , MicroRNAs/fisiologia , Animais , Feminino , Hepatite Alcoólica/genética , Hepatite Alcoólica/fisiopatologia , Hepatócitos/fisiologia , Humanos , Hepatopatias Alcoólicas/genética , Proteína 1 de Membrana Associada ao Lisossomo/fisiologia , Proteína 2 de Membrana Associada ao Lisossomo/fisiologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Serina-Treonina Quinases TOR/fisiologiaRESUMO
Although mortality due to acute alcoholic hepatitis (AH) correlates with Model for End-Stage Liver Disease (MELD) scores, biomarkers are critically needed to manage this disease. Increases in inflammatory markers and macrophage activation are associated with acute AH and could be potential biomarkers of clinical events and/or mortality. We enrolled 89 clinically diagnosed AH patients in four US academic medical centers. Plasma from AH patients had a significant increase in gut microbial translocation indicators (endotoxin, bacterial 16S ribosomal DNA) and host response indicators (soluble cluster of differentiation 14 [sCD14] and lipopolysaccharide binding protein [LBP]) compared to controls. Patient MELD score and Glasgow Alcoholic Hepatitis score (GAHS) correlated with endotoxin levels. AH patients also had a significant increase in high mobility group protein 1 (HMGB1), a sterile danger signal molecule, and osteopontin (OPN), a multifunctional phosphoprotein involved in neutrophil activation, compared to controls. Increased levels of OPN positively correlated with increasing MELD score, GAHS, and LBP levels. Consistent with these results, AH patients had significantly increased circulating levels of macrophage activation (sCD163 and sCD206) markers compared to healthy controls, and sCD163 and sCD206 significantly and positively correlated with OPN, HMGB1, and LBP levels as well as with MELD score and GAHS. These findings indicate a connection between microbial translocation, immune cell activation, and AH severity. Plasma sCD14, OPN, sCD163, and sCD206 levels were significantly higher in nonsurvivors than survivors. In multivariate regression models, we identified sCD14, sCD163, and OPN as independent predictors of 90-day mortality, infection, and organ failure development, respectively. Conclusion: Our study suggests that sCD14, LBP, OPN, sCD163, and sCD206 are biomarkers to indicate severity and predict clinical outcomes in AH.
Assuntos
Proteínas de Fase Aguda/metabolismo , Antígenos CD/metabolismo , Proteínas de Transporte/metabolismo , Progressão da Doença , Hepatite Alcoólica/mortalidade , Hepatite Alcoólica/fisiopatologia , Ativação de Macrófagos/imunologia , Glicoproteínas de Membrana/metabolismo , Centros Médicos Acadêmicos , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Causas de Morte , Ensaio de Imunoadsorção Enzimática , Hepatite Alcoólica/sangue , Humanos , Estimativa de Kaplan-Meier , Testes de Função Hepática , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Medição de Risco , Índice de Gravidade de Doença , Análise de Sobrevida , Estados UnidosRESUMO
Kupffer cell and macrophage (MØ) activation contributes to steatosis, inflammation, and fibrosis in alcoholic liver disease (ALD). We found increased frequency of MØ, T cells, and expression of C-C chemokine receptor type 2 (Ccr2) and C-C chemokine receptor type 5 (Ccr5) in the livers of patients with ALD, and increased circulating chemokines, C-C chemokine ligand types 2 (CCL2), and C-C chemokine ligand types 5 (CCL5) in patients with alcoholic hepatitis. We hypothesized that inhibition of CCL2 signaling with the dual CCR2/5 inhibitor, cenicriviroc (CVC), would attenuate ALD. In a mouse model of ALD, liver injury (alanine aminotransferase [ALT]) and steatosis were prevented by CVC whether administered as "prevention" throughout the alcohol feeding or as "treatment" started after the development of ALD. Alcohol-induced increases in early liver fibrosis markers (sirius red, hydroxyproline, and collagen-1) were normalized by both modes of CVC administration. We found that prevention and treatment with CVC reversed alcohol-related increases in liver mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and CCL2. CVC administration regimens prevented the increase in infiltrating MØ (F4/80lo CD11bhi ) and reduced proinflammatory Ly6Chi MØ in livers of alcohol-fed mice. CVC increased liver T-cell numbers and attenuated Il-2 expression without an effect on CD69+ or CD25+ T-cell expression. In vitro, CVC inhibited CCL2-induced increases in hepatocyte fatty acid synthase (Fasn) and adipose differentiation-related protein (Adrp), whereas it augmented acyl-coenzyme A oxidase 1 (Acox-1), proliferator-activated receptor gamma co-activator alpha (Pgc1α) and uncoupling protein 2 expression, suggesting mechanisms for attenuated hepatocyte steatosis. We found that CCL2 and CCL5 sensitized hepatocytes to lipopolysaccharide-induced liver injury (TNF-α, ALT, and lactate dehydrogenase release). Alcohol feeding induced apoptosis (poly ADP-ribose polymerase [PARP] and caspase-3 [CASP-3] cleavage) and pyroptosis (gasdermin D [GSDMD] cleavage) in livers, and CVC prevented both of these forms of cell death. Conclusion: Together, our data demonstrate preclinical evidence for CCR2/CCR5 inhibition with CVC as a potent intervention to ameliorate alcohol-induced steatohepatitis and liver damage.
Assuntos
Antagonistas dos Receptores CCR5/uso terapêutico , Hepatopatias Alcoólicas/tratamento farmacológico , Receptores CCR2/antagonistas & inibidores , Animais , Fígado Gorduroso Alcoólico/tratamento farmacológico , Feminino , Hepatite Alcoólica/tratamento farmacológico , Cirrose Hepática Alcoólica/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacosRESUMO
Inflammatory cell activation drives diverse cellular programming during hepatic diseases. Hypoxia-inducible factors (HIFs) have recently been identified as important regulators of immunity and inflammation. In nonalcoholic steatohepatitis (NASH), HIF-1α is upregulated in hepatocytes, where it induces steatosis; however, the role of HIF-1α in macrophages under metabolic stress has not been explored. In this study, we found increased HIF-1α levels in hepatic macrophages in methionine-choline-deficient (MCD) diet-fed mice and in macrophages of patients with NASH compared with controls. The HIF-1α increase was concomitant with elevated levels of autophagy markers BNIP3, Beclin-1, LC3-II, and p62 in both mouse and human macrophages. LysMCre HIFdPA fl/fl mice, which have HIF-1α levels stabilized in macrophages, showed higher steatosis and liver inflammation compared with HIFdPA fl/fl mice on MCD diet. In vitro and ex vivo experiments reveal that saturated fatty acid, palmitic acid (PA), both induces HIF-1α and impairs autophagic flux in macrophages. Using small interfering RNA-mediated knock-down and overexpression of HIF-1α in macrophages, we demonstrated that PA impairs autophagy via HIF-1α. We found that HIF-1α mediates NF-κB activation and MCP-1 production and that HIF-1α-mediated impairment of macrophage autophagy increases IL-1ß production, contributing to MCD diet-induced NASH. Conclusion: Palmitic acid impairs autophagy via HIF-1α activation in macrophages. HIF-1α and impaired autophagy are present in NASH in vivo in mouse macrophages and in human blood monocytes. We identified that HIF-1α activation and decreased autophagic flux stimulate inflammation in macrophages through upregulation of NF-κB activation. These results suggest that macrophage activation in NASH involves a complex interplay between HIF-1α and autophagy as these pathways promote proinflammatory overactivation in MCD diet-induced NASH.
Assuntos
Autofagia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Macrófagos/metabolismo , Hepatopatia Gordurosa não Alcoólica/imunologia , Animais , Estudos de Casos e Controles , Feminino , Masculino , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ácido PalmíticoRESUMO
BACKGROUND: Alcohol use disorder is a significant societal and medical burden that is associated with both organ pathology and addiction. Excessive alcohol use results in neuroinflammation characterized by activation of the inflammasome, a multiprotein complex, and IL-1ß increase in the brain. Recent studies suggest that inflammation could contribute to alcohol addiction. Here, we targeted components of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome cascade, which senses and responds to immunologic stimuli, to determine whether NLRP3 inhibition modulates alcohol consumption. METHODS: C57BL/6J male and female mice were provided a 2-bottle choice of alcohol at increasing concentrations (3, 6, 9, and 12%, 4 days each) or water, and some were treated with daily injections of an NLRP3 inhibitor (MCC950), a caspase-1 inhibitor (VX765), IL-1 receptor antagonist (IL-1ra; anakinra), or vehicle injection. RESULTS: Treatment with VX765, MCC950, and IL-1ra significantly reduced alcohol consumption and preference in female mice (p < 0.05). Treatment with MCC950 and IL-1ra reduced alcohol consumption, while IL-1ra reduced alcohol preference in male mice (p < 0.05). VX765 did not affect alcohol consumption or preference in male mice. CONCLUSIONS: These findings highlight gender differences in alcohol preference and demonstrate that inhibition of different steps in inflammasome signaling can reduce alcohol consumption in females. Inhibition of NLRP3 inflammasome activation and the inflammasome-IL-1ß cascade opens novel insights into the development of new therapies to address alcohol use disorder in an era of targeted and precision medicine.
Assuntos
Consumo de Bebidas Alcoólicas/tratamento farmacológico , Consumo de Bebidas Alcoólicas/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Caracteres Sexuais , Transdução de Sinais/efeitos dos fármacos , Animais , Dipeptídeos/administração & dosagem , Feminino , Furanos , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Indenos , Inflamassomos/antagonistas & inibidores , Inflamassomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/fisiologia , Sulfonamidas , Sulfonas/administração & dosagem , para-Aminobenzoatos/administração & dosagemRESUMO
BACKGROUND & AIMS: Chronic, excessive alcohol consumption leads to alcoholic liver disease (ALD) characterized by steatosis, inflammation, and eventually cirrhosis. The hepatocyte specific microRNA 122 (MIR122) regulates hepatocyte differentiation and metabolism. We investigated whether an alcohol-induced decrease in level of MIR122 contributes to development of ALD. METHODS: We obtained liver samples from 12 patients with ALD and cirrhosis and 9 healthy individuals (controls) and analyzed them by histology and immunohistochemistry. C57Bl/6 mice were placed on a Lieber-DeCarli liquid diet, in which they were fed ethanol for 8 weeks, as a model of ALD, or a control diet. These mice were also given injections of CCl4, to increase liver fibrosis, for 8 weeks. On day 28, mice with ethanol-induced liver disease and advanced fibrosis, and controls, were given injections of recombinant adeno-associated virus 8 vector that expressed the primary miR-122 transcript (pri-MIR122, to overexpress MIR122 in hepatocytes) or vector (control). Two weeks before ethanol feeding, some mice were given injections of a vector that expressed an anti-MIR122, to knock down its expression. Serum and liver tissues were collected; hepatocytes and liver mononuclear cells were analyzed by histology, immunoblots, and confocal microscopy. We performed in silico analyses to identify targets of MIR122 and chromatin immunoprecipitation quantitative polymerase chain reaction analyses in Huh-7 cells. RESULTS: Levels of MIR122 were decreased in liver samples from patients with ALD and mice on the Lieber-DeCarli diet, compared with controls. Transgenic expression of MIR122 in hepatocytes of mice with ethanol-induced liver disease and advanced fibrosis significantly reduced serum levels of alanine aminotransferase (ALT) and liver steatosis and fibrosis, compared with mice given injections of the control vector. Ethanol feeding reduced expression of pri-MIR122 by increasing expression of the spliced form of the transcription factor grainyhead like transcription factor 2 (GRHL2) in liver tissues from mice. Levels of GRHL2 also were increased in liver tissues from patients with ALD, compared with controls; increases correlated with decreases in levels of MIR122 in human liver. Mice given injections of the anti-MIR122 before ethanol feeding had increased steatosis, inflammation, and serum levels of alanine aminotransferase compared with mice given a control vector. Levels of hypoxia-inducible factor 1 alpha (HIF1α) mRNA, a target of MIR122, were increased in liver tissues from patients and mice with ALD, compared with controls. Mice with hepatocyte-specific disruption of Hif1α developed less-severe liver injury following administration of ethanol, injection of anti-MIR122, or both. CONCLUSIONS: Levels of MIR122 decrease in livers from patients with ALD and mice with ethanol-induced liver disease, compared with controls. Transcription of MIR122 is inhibited by GRHL2, which is increased in livers of mice and patients with ALD. Expression of an anti-MIR122 worsened the severity of liver damage following ethanol feeding in mice. MIR122 appears to protect the liver from ethanol-induced damage by reducing levels of HIF1α. These processes might be manipulated to reduce the severity of ALD in patients.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/prevenção & controle , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Adulto , Idoso , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Feminino , Hepatócitos/metabolismo , Humanos , Hepatopatias Alcoólicas/patologia , Masculino , Camundongos , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Alcoholic liver disease (ALD) is a global health problem with limited therapeutic options. Intestinal barrier integrity and the microbiota modulate susceptibility to ALD. Akkermansia muciniphila, a Gram-negative intestinal commensal, promotes barrier function partly by enhancing mucus production. The aim of this study was to investigate microbial alterations in ALD and to define the impact of A. muciniphila administration on the course of ALD. DESIGN: The intestinal microbiota was analysed in an unbiased approach by 16S ribosomal DNA (rDNA) sequencing in a Lieber-DeCarli ALD mouse model, and faecal A. muciniphila abundance was determined in a cohort of patients with alcoholic steatohepatitis (ASH). The impact of A. muciniphila on the development of experimental acute and chronic ALD was determined in a preventive and therapeutic setting, and intestinal barrier integrity was analysed. RESULTS: Patients with ASH exhibited a decreased abundance of faecal A. muciniphila when compared with healthy controls that indirectly correlated with hepatic disease severity. Ethanol feeding of wild-type mice resulted in a prominent decline in A. muciniphila abundance. Ethanol-induced intestinal A. muciniphila depletion could be restored by oral A. muciniphila supplementation. Furthermore, A. muciniphila administration when performed in a preventive setting decreased hepatic injury, steatosis and neutrophil infiltration. A. muciniphila also protected against ethanol-induced gut leakiness, enhanced mucus thickness and tight-junction expression. In already established ALD, A. muciniphila used therapeutically ameliorated hepatic injury and neutrophil infiltration. CONCLUSION: Ethanol exposure diminishes intestinal A. muciniphila abundance in both mice and humans and can be recovered in experimental ALD by oral supplementation. A. muciniphila promotes intestinal barrier integrity and ameliorates experimental ALD. Our data suggest that patients with ALD might benefit from A. muciniphila supplementation.
Assuntos
Etanol/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Hepatopatias Alcoólicas/microbiologia , Verrucomicrobia/efeitos dos fármacos , Adulto , Idoso , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Feminino , Imunofluorescência , Microbioma Gastrointestinal/genética , Humanos , Imuno-Histoquímica , Fígado , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Verrucomicrobia/fisiologiaRESUMO
BACKGROUND & AIMS: Neutrophil extracellular traps (NETs) are an important strategy utilized by neutrophils to immobilize and kill invading microorganisms. Herein, we studied NET formation and the process of neutrophil cell death (NETosis), as well as the clearance of NETs by macrophages (MΦ) (efferocytosis) in acute sepsis following binge drinking. METHODS: Healthy volunteers consumed 2â¯ml of vodka/kg body weight, before blood endotoxin and 16â¯s rDNA were measured. Peripheral neutrophils were isolated and exposed to alcohol followed by phorbol 12-myristate 13-acetate (PMA) stimulation. Mice were treated with three alcohol binges and intraperitoneal lipopolysaccharide (LPS) to assess the dynamics of NET formation and efferocytosis. In vivo, anti-Ly6G antibody (IA8) was used for neutrophil depletion. RESULTS: Inducers of NETs (endotoxin and bacterial DNA) significantly increased in the circulation after binge alcohol drinking in humans. Ex vivo, alcohol alone increased NET formation, but upon PMA stimulation alcohol attenuated NET formation. Binge alcohol in mice resulted in a biphasic response to LPS. Initially, binge alcohol reduced LPS-induced NET formation and resulted in a diffuse distribution of neutrophils in the liver compared to alcohol-naïve mice. Moreover, indicators of NET formation including citrullinated histone H3, neutrophil elastase, and neutrophil myeloperoxidase were decreased at an early time point after LPS challenge in mice receiving binge alcohol, suggesting decreased NET formation. However, in the efferocytosis phase (15â¯h after LPS) citrullinated histone-H3 was increased in the liver in alcohol binge mice, suggesting decreased clearance of NETs. In vitro alcohol treatment reduced efferocytosis and phagocytosis of NETotic neutrophils and promoted expression of CD206 on MΦ. Finally, depletion of neutrophils prior to binge alcohol ameliorated LPS-induced systemic inflammation and liver injury in mice. CONCLUSIONS: Dysfunctional NETosis and efferocytosis following binge drinking exacerbate liver injury associated with sepsis. LAY SUMMARY: Disease severity in alcoholic liver disease (ALD) is associated with a significant presence of neutrophils (a type of immune cell) in the liver. It remains unknown how alcohol affects the capacity of neutrophils to control infection, a major hallmark of ALD. We found that binge alcohol drinking impaired important strategies used by neutrophils to contain and resolve infection, resulting in increased liver injury during ALD.
Assuntos
Consumo Excessivo de Bebidas Alcoólicas/complicações , Armadilhas Extracelulares/fisiologia , Hepatite Alcoólica/etiologia , Macrófagos/fisiologia , Fagocitose , Sepse/etiologia , Animais , Proteína HMGB1/fisiologia , Humanos , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: The end-organ effects of alcohol span throughout the entire body, from the gastrointestinal tract to the central nervous system (CNS). In the intestine, alcohol use changes the microbiome composition and increases gut permeability allowing translocation of microbial components into the circulation. Gut-derived pathogen-associated signals initiate inflammatory responses in the liver and possibly elsewhere in the body. Because previous studies showed that the gut microbiome contributes to alcohol-induced liver disease, we hypothesized that antibiotic administration to reduce the gut microbiome would attenuate alcohol-induced inflammation in the brain and small intestine (SI). METHODS: Six- to 8-week-old C57BL/6J female mice were fed alcohol in a liquid diet or a calorie-matched control diet for 10 days with an acute alcohol binge or sugar on the final day (acute-on-chronic alcohol administration). Some mice were treated with oral antibiotics daily to diminish the gut microbiome. We compared serum levels of TNFα, IL-6, and IL-1ß by ELISA; expression of cytokines Tnfα, Mcp1, Hmgb1, Il-17, Il-23, Il-6, and Cox2; and inflammasome components Il-1ß, Il-18, Casp1, Asc, and Nlrp3 in the CNS and SI by qRT-PCR. Microglial morphology was analyzed using immunohistochemical IBA1 staining in the cortex and hippocampus. RESULTS: Antibiotics dramatically reduced the gut microbiome load in both alcohol- and pair-fed mice. Alcohol-induced neuroinflammation and increase in SI cytokine expression were attenuated in mice with antibiotic treatment. Acute-on-chronic alcohol did not induce serum TNFα, IL-6, and IL-1ß. Alcohol feeding significantly increased the expression of proinflammatory cytokines such as Tnfα, Mcp1, Hmgb1, Il-17, and Il-23 in the brain and intestine. Reduction in the gut bacterial load, as a result of antibiotic treatment, attenuated the expression of all of these alcohol-induced proinflammatory cytokines in both the brain and SI. Alcohol feeding resulted in microglia activation and morphologic changes in the cortex and hippocampus characterized by a reactive phenotype. These alcohol-induced changes were abrogated following an antibiotic-induced reduction in the gut microbiome. Unexpectedly, antibiotic treatment increased the mRNA expression of some inflammasome components in both the brain and intestine. CONCLUSIONS: Our data show for the first time that the acute-on-chronic alcohol administration in mice induces both neuroinflammation and intestinal inflammation and that reduction in the intestinal bacterial load can attenuate alcohol-associated CNS and gut inflammation. Gut microbiome-derived signals contribute to neuroinflammation in acute-on-chronic alcohol exposure.
Assuntos
Encéfalo/metabolismo , Depressores do Sistema Nervoso Central/toxicidade , Citocinas/sangue , Encefalite/induzido quimicamente , Etanol/toxicidade , Inflamassomos/metabolismo , Animais , Antibacterianos/uso terapêutico , Encéfalo/patologia , Modelos Animais de Doenças , Encefalite/tratamento farmacológico , Feminino , Microbioma Gastrointestinal , Inflamassomos/genética , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Intestinos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Fatores de TempoRESUMO
Amyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disorder resulting from motor neuron death. Approximately 10% of cases are familial (FALS), typically with a dominant inheritance mode. Despite numerous advances in recent years, nearly 50% of FALS cases have unknown genetic aetiology. Here we show that mutations within the profilin 1 (PFN1) gene can cause FALS. PFN1 is crucial for the conversion of monomeric (G)-actin to filamentous (F)-actin. Exome sequencing of two large ALS families showed different mutations within the PFN1 gene. Further sequence analysis identified 4 mutations in 7 out of 274 FALS cases. Cells expressing PFN1 mutants contain ubiquitinated, insoluble aggregates that in many cases contain the ALS-associated protein TDP-43. PFN1 mutants also display decreased bound actin levels and can inhibit axon outgrowth. Furthermore, primary motor neurons expressing mutant PFN1 display smaller growth cones with a reduced F/G-actin ratio. These observations further document that cytoskeletal pathway alterations contribute to ALS pathogenesis.
Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Predisposição Genética para Doença/genética , Proteínas Mutantes/metabolismo , Mutação/genética , Profilinas/genética , Profilinas/metabolismo , Actinas/metabolismo , Sequência de Aminoácidos , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/metabolismo , Animais , Axônios/metabolismo , Axônios/patologia , Células Cultivadas , Exoma/genética , Feminino , Cones de Crescimento/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Judeus/genética , Masculino , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Neurônios Motores/citologia , Neurônios Motores/metabolismo , Proteínas Mutantes/genética , Linhagem , Conformação Proteica , Ubiquitinação , População Branca/genéticaRESUMO
Fibrosis, driven by inflammation, marks the transition from benign to progressive stages of chronic liver diseases. Although inflammation promotes fibrogenesis, it is not known whether other events, such as hepatocyte death, are required for the development of fibrosis. Interferon regulatory factor 3 (IRF3) regulates hepatocyte apoptosis and production of type I IFNs. In the liver, IRF3 is activated via Toll-like receptor 4 (TLR4) signaling or the endoplasmic reticulum (ER) adapter, stimulator of interferon genes (STING). We hypothesized that IRF3-mediated hepatocyte death is an independent determinant of chemically induced liver fibrogenesis. To test this, we performed acute or chronic CCl4 administration to WT and IRF3-, Toll/Interleukin-1R (TIR) domain-containing adapter-inducing interferon-ß (TRIF)-, TRIF-related adaptor molecule (TRAM)-, and STING-deficient mice. We report that acute CCl4 administration to WT mice resulted in early ER stress, activation of IRF3, and type I IFNs, followed by hepatocyte apoptosis and liver injury, accompanied by liver fibrosis upon repeated administration of CCl4 Deficiency of IRF3 or STING prevented hepatocyte death and fibrosis both in acute or chronic CCl4 In contrast, mice deficient in type I IFN receptors or in TLR4 signaling adaptors, TRAM or TRIF, upstream of IRF3, were not protected from hepatocyte death and/or fibrosis, suggesting that the pro-apoptotic role of IRF3 is independent of TLR signaling in fibrosis. Hepatocyte death is required for liver fibrosis with causal involvement of STING and IRF3. Thus, our results identify that IRF3, by its association with STING in the presence of ER stress, couples hepatocyte apoptosis with liver fibrosis and indicate that innate immune signaling regulates outcomes of liver fibrosis via modulation of hepatocyte death in the liver.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Estresse do Retículo Endoplasmático , Hepatócitos/patologia , Fator Regulador 3 de Interferon/fisiologia , Cirrose Hepática/etiologia , Proteínas de Membrana/fisiologia , Receptor de Interferon alfa e beta/fisiologia , Animais , Tetracloreto de Carbono/toxicidade , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Hepatócitos/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismoRESUMO
UNLABELLED: The spectrum of alcoholic liver disease (ALD) is a major cause of mortality with limited therapies available. Because alcohol targets numerous signaling pathways in hepatocytes and in immune cells, the identification of a master regulatory target that modulates multiple signaling processes is attractive. In this report, we assessed the role of spleen tyrosine kinase (SYK), a nonreceptor tyrosine kinase, which has a central modulatory role in multiple proinflammatory signaling pathways involved in the pathomechanism of ALD. Using mouse disease models that represent various phases in the progression of human ALD, we found that alcohol, in all of these models, induced SYK activation in the liver, both in hepatocytes and liver mononuclear cells. Furthermore, significant SYK activation also occurred in liver samples and peripheral blood mononuclear cells of patients with ALD/alcoholic hepatitis compared to controls. Functional inhibition of SYK activation in vivo abrogated alcohol-induced hepatic neutrophil infiltration, resident immune cell activation, as well as inflammasome and extracellular signal-regulated kinase 1 and 2-mediated nuclear factor kappa B activation in mice. Strikingly, inhibition of SYK activation diminished alcohol-induced hepatic steatosis and interferon regulatory factor 3-mediated apoptosis. CONCLUSION: Our data demonstrate a novel, functional, and multicellular role for SYK phosphorylation in modulating immune cell-driven liver inflammation, hepatocyte cell death, and steatosis at different stages of ALD. These novel findings highlight SYK as a potential multifunctional target in the treatment of alcoholic steatohepatitis. (Hepatology 2016;64:1057-1071).
Assuntos
Morte Celular , Fígado Gorduroso/prevenção & controle , Hepatócitos/patologia , Inflamação/prevenção & controle , Hepatopatias Alcoólicas/enzimologia , Oxazinas/farmacologia , Oxazinas/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Quinase Syk/antagonistas & inibidores , Animais , Fígado Gorduroso/etiologia , Feminino , Humanos , Inflamação/etiologia , Hepatopatias Alcoólicas/complicações , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Several studies have suggested an increased frequency of variants in the gene encoding angiogenin (ANG) in patients with amyotrophic lateral sclerosis (ALS). Interestingly, a few ALS patients carrying ANG variants also showed signs of Parkinson disease (PD). Furthermore, relatives of ALS patients have an increased risk to develop PD, and the prevalence of concomitant motor neuron disease in PD is higher than expected based on chance occurrence. We therefore investigated whether ANG variants could predispose to both ALS and PD. METHODS: We reviewed all previous studies on ANG in ALS and performed sequence experiments on additional samples, which allowed us to analyze data from 6,471 ALS patients and 7,668 controls from 15 centers (13 from Europe and 2 from the USA). We sequenced DNA samples from 3,146 PD patients from 6 centers (5 from Europe and 1 from the USA). Statistical analysis was performed using the variable threshold test, and the Mantel-Haenszel procedure was used to estimate odds ratios. RESULTS: Analysis of sequence data from 17,258 individuals demonstrated a significantly higher frequency of ANG variants in both ALS and PD patients compared to control subjects (p = 9.3 × 10(-6) for ALS and p = 4.3 × 10(-5) for PD). The odds ratio for any ANG variant in patients versus controls was 9.2 for ALS and 6.7 for PD. INTERPRETATION: The data from this multicenter study demonstrate that there is a strong association between PD, ALS, and ANG variants. ANG is a genetic link between ALS and PD.
Assuntos
Esclerose Lateral Amiotrófica/genética , Predisposição Genética para Doença , Variação Genética/genética , Doença de Parkinson/genética , Ribonuclease Pancreático/genética , Bases de Dados Factuais/estatística & dados numéricos , Europa (Continente) , Feminino , Humanos , Masculino , Estudos Multicêntricos como Assunto , Estados UnidosRESUMO
A higher prevalence of intermediate ataxin-2 CAG repeats in amyotrophic lateral sclerosis (ALS) patients has raised the possibility that CAG expansions in other polyglutamine disease genes could contribute to ALS neurodegeneration. We sought to determine whether expansions of the CAG repeat of the HTT gene that causes Huntington's disease, are associated with ALS. We compared the HTT CAG repeat length on a total of 3144 chromosomes from 1572 sporadic ALS patients and 4007 control chromosomes, and also tested its possible effects on ALS-specific parameters, such as age and site of onset and survival rate. Our results show that the CAG repeat in the HTT gene is not a risk factor for ALS nor modifies its clinical presentation. These findings suggest that distinct neuronal degeneration processes are involved in these two different neurodegenerative disorders.
Assuntos
Esclerose Lateral Amiotrófica/genética , Doença de Huntington/genética , Proteínas do Tecido Nervoso/genética , Expansão das Repetições de Trinucleotídeos , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Esclerose Lateral Amiotrófica/metabolismo , Humanos , Proteína Huntingtina , Pessoa de Meia-Idade , Peptídeos/metabolismo , Prevalência , Fatores de Risco , Adulto JovemRESUMO
Massive inflammation and liver failure are main contributors to the high mortality in alcohol-associated hepatitis (AH). In recent clinical trials, granulocyte colony-stimulating factor (G-CSF) therapy improved liver function and survival in patients with AH. However, the mechanisms of G-CSF-mediated beneficial effects in AH remain elusive. In this study, we evaluated effects of in vivo G-CSF administration, using a mouse model of AH. G-CSF treatment significantly reduced liver damage in alcohol-fed mice even though it increased the numbers of liver-infiltrating immune cells, including neutrophils and inflammatory monocytes. Moreover, G-CSF promoted macrophage polarization toward an M2-like phenotype and increased hepatocyte proliferation, which was indicated by an increased Ki67-positive signal colocalized with hepatocyte nuclear factor 4 alpha (HNF-4α) and cyclin D1 expression in hepatocytes. We found that G-CSF increased G-CSF receptor expression and resulted in reduced levels of phosphorylated ß-catenin in hepatocytes. In the presence of an additional pathogen-associated molecule, lipopolysaccharide (LPS), which is significantly increased in the circulation and liver of patients with AH, the G-CSF-induced hepatoprotective effects were abolished in alcohol-fed mice. We still observed increased Ki67-positive signals in alcohol-fed mice following G-CSF treatment; however, Ki67 and HNF-4α did not colocalize in LPS-challenged mice. Conclusion: G-CSF treatment increases immune cell populations, particularly neutrophil counts, and promotes M2-like macrophage differentiation in the liver. More importantly, G-CSF treatment reduces alcohol-induced liver injury and promotes hepatocyte proliferation in alcohol-fed mice. These data provide new insights into the understanding of mechanisms mediated by G-CSF and its therapeutic effects in AH.
Assuntos
Hepatite Alcoólica , Proliferação de Células , Etanol/metabolismo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Hepatite Alcoólica/tratamento farmacológico , Hepatócitos , Humanos , Antígeno Ki-67/metabolismo , Lipopolissacarídeos/metabolismo , MacrófagosRESUMO
[This corrects the article DOI: 10.1371/journal.pone.0174544.].