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Open Partial Horizontal Laryngectomy (OPHL) Type IIa surgery is a conservative surgical technique used in the treatment of laryngeal carcinomas. In this pilot study, we aimed to characterize swallowing function and physiology in a series of patients after OPHL Type IIa surgery through comparison to healthy reference values for quantitative measures for videofluoroscopy. We performed retrospective quantitative analysis of videofluoroscopy recordings of thin liquid swallows for a preliminary sample of 10 male patients. Each videofluoroscopy clip was rated in triplicate by trained blinded raters according to the ASPEKT Method (Analysis of Swallowing Physiology: Events, Kinematics and Timing). This preliminary sample of patients with previous OPHL surgery showed functional airway protection, with only 2 patients showing incomplete laryngeal vestibule closure (LVC) and associated airway invasion. However, the majority of patients (90%) showed prolonged latencies to LVC and upper esophageal sphincter (UES) opening. Prolonged durations of LVC and UES opening were also noted, but these were in the direction of compensation rather than impairment. Reduced pharyngeal area at rest was seen in 70% of the sample, and all patients showed poor pharyngeal constriction. Post-swallow residue was a prominent finding in ≥ 75% of these patients. In particular, reduced or absent constriction of the hypopharynx in the region of the pyriform sinuses was noted as a characteristic of swallowing in this sample. The data from these patients suggest that despite functional airway protection, severe swallowing dysfunction involving poor pharyngeal constriction and bolus clearance may be likely after OPHL surgery.
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Arthritis can be defined as a painful musculoskeletal disorder that affects the joints. Hesperidin methyl chalcone (HMC) is a flavonoid with analgesic, anti-inflammatory, and antioxidant effects. However, its effects on a specific cell type and in the zymosan-induced inflammation are unknown. We aimed at evaluating the effects of HMC in a zymosan-induced arthritis model. A dose-response curve of HMC (10, 30, or 100 mg/kg) was performed to determine the most effective analgesic dose after intra-articular zymosan stimuli. Knee joint oedema was determined using a calliper. Leukocyte recruitment was performed by cell counting on knee joint wash as well as histopathological analysis. Oxidative stress was measured by colorimetric assays (GSH, FRAP, ABTS and NBT) and RT-qPCR (gp91phox and HO-1 mRNA expression) performed. In vitro, oxidative stress was assessed by DCFDA assay using RAW 264.7 macrophages. Cytokine production was evaluated in vivo and in vitro by ELISA. In vitro NF-κB activation was analysed by immunofluorescence. We observed HMC reduced mechanical hypersensitivity and knee joint oedema, leukocyte recruitment, and pro-inflammatory cytokine levels. We also observed a reduction in zymosan-induced oxidative stress as per increase in total antioxidant capacity and reduction in gp91phox and increase in HO-1 mRNA expression. Accordingly, total ROS production and macrophage NFκB activation were diminished. HMC interaction with NFκB p65 at Ser276 was revealed using molecular docking analysis. Thus, data presented in this work suggest the usefulness of HMC as an analgesic and anti-inflammatory in a zymosan-induced arthritis model, possibly by targeting NFκB activation in macrophages.
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Artralgia/tratamento farmacológico , Chalconas/farmacologia , Hesperidina/análogos & derivados , Inflamação/tratamento farmacológico , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , NF-kappa B/metabolismo , Zimosan/farmacologia , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/fisiologia , Artralgia/induzido quimicamente , Artralgia/metabolismo , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/metabolismo , Hesperidina/farmacologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Simulação de Acoplamento Molecular/métodos , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacosRESUMO
Type 1 diabetes enhances susceptibility to infection and favors the sepsis development. In addition, diabetic mice produced higher levels of histamine in several tissues and in the blood after LPS stimulation than nondiabetic mice. In this study, we aimed to explore the role of mast cells (MCs) and histamine in neutrophil migration and, consequently, infection control in diabetic mice with mild sepsis (MS) induced by cecum ligation and puncture. We used female BALB/c, MC-sufficient (WB/B6), MC-deficient (W/W(v)), and NOD mice. Diabetic mice given MS displayed 100% mortality within 24 h, whereas all nondiabetic mice survived for at least 5 d. The mortality rate of diabetic mice was reduced to 57% after the depletion of MC granules with compound 48/80. Moreover, this pretreatment increased neutrophil migration to the focus of infection, which reduced systemic inflammatory response and bacteremia. The downregulation of CXCR2 and upregulation of G protein-coupled receptor kinase 2 in neutrophils was prevented by pretreatment of diabetic mice given MS with compound 48/80. In addition, blocking the histamine H2 receptor restored neutrophil migration, enhanced CXCR2 expression, decreased bacteremia, and improved sepsis survival in alloxan-induced diabetic and spontaneous NOD mice. Finally, diabetic W/W(v) mice had neutrophil migration to the peritoneal cavity, increased CXCR2 expression, and reduced bacteremia compared with diabetic WB/B6 mice. These results demonstrate that histamine released by MCs reduces diabetic host resistance to septic peritonitis in mice.
Assuntos
Diabetes Mellitus Experimental/mortalidade , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Mastócitos/imunologia , Neutrófilos/metabolismo , Receptores de Interleucina-8B/metabolismo , Aloxano , Animais , Bacteriemia/tratamento farmacológico , Movimento Celular , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/microbiologia , Regulação para Baixo/efeitos dos fármacos , Feminino , Histamina/metabolismo , Antagonistas dos Receptores H2 da Histamina , Inflamação/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Receptores Histamínicos H2/metabolismo , Sepse/complicações , Sepse/microbiologia , Sepse/mortalidade , Regulação para Cima/efeitos dos fármacos , p-Metoxi-N-metilfenetilamina/farmacologiaRESUMO
Clearance of apoptotic cells (efferocytosis) is critical to the homeostasis of the immune system by restraining inflammation and autoimmune response to intracellular Ags released from dying cells. TLRs-mediated innate immunity plays an important role in pathogen clearance and in regulation of the adaptive immune response. However, the regulation of efferocytosis by activation of TLRs has not been well characterized. In this study, we found that activation of TLR3 or TLR9, but not of TLR2, enhances engulfment of apoptotic cells by macrophages. We found that the activation of TLR3 upregulates the expression of triggering receptor expressed on myeloid cells (TREM)-like protein 2 (TLT2), a member of the TREM receptor family, on the surface of macrophages. Blocking TLT2 on the macrophage surface by either specific anti-TLT2 Ab or soluble TLT2 extracellular domain attenuated the enhanced ability of macrophages with TLR3 activation to engulf apoptotic cells. To the contrary, overexpression of TLT2 increased the phagocytosis of apoptotic cells. We found that TLT2 specifically binds to phosphatidylserine, a major "eat me" signal that is exposed on the surface of apoptotic cells. Furthermore, we found that TLT2 mediates phagocytosis of apoptotic cells in vivo. Thus, our studies identified TLT2 as an engulfment receptor for apoptotic cells. Our data also suggest a novel mechanism by which TREM receptors regulate inflammation and autoimmune response.
Assuntos
Apoptose/imunologia , Macrófagos/imunologia , Fagocitose/imunologia , Receptores Imunológicos/imunologia , Transdução de Sinais/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunidade Inata/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Receptores Imunológicos/metabolismo , Receptor 3 Toll-Like/imunologia , Receptor 3 Toll-Like/metabolismoRESUMO
BACKGROUND: Sepsis is a complex condition characterized by systemic host inflammation caused by an infection. Experimental and observational studies indicate that obesity, one of the components of metabolic syndrome (MetS), or aspirin (ASA) treatment could be associated with sepsis survival. However, the effects of ASA on septic mice with MetS-induced conditions have not been explored. METHODS: Swiss mice were administered monosodium glutamate (MSG) (4 mg/kg) during their first 5 days of life for MetS induction, while the control mice received an equimolar saline solution. MetS was validated in male mice on their 60th day of life. ASA treatment was administered for 15 days prior to sepsis (40 mg/kg). On the 75th day, sepsis was induced in MetS and control mice through cecal ligation and puncture (CLP). The effects of ASA on septic mice with MSG-induced MetS were assessed by determining survival rates, quantification of nitric oxide (NO), and cytokine levels in the plasma, while correlating these data with hematological, blood glucose and cardiovascular parameters. RESULTS: MetS was validated by Lee-Index (3 body weight/naso-anal length×1000), hypertension, and hyperglycemia in animals receiving MSG as neonates. In control animals, severe sepsis promoted hypoglycemia, which was associated with mortality, as well as increased plasma NO levels, hypotension, hematological alterations, and elevation of proinflammatory cytokines. In contrast, MetS and pre-treatment with ASA were able to prevent sepsis-related alterations. CONCLUSIONS: MetS and ASA pre-treatment provided protection against severe sepsis. However, ASA was ineffective in mice with MetS undergoing severe sepsis.
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Aspirina , Citocinas , Síndrome Metabólica , Óxido Nítrico , Sepse , Animais , Sepse/tratamento farmacológico , Aspirina/uso terapêutico , Aspirina/administração & dosagem , Camundongos , Masculino , Síndrome Metabólica/tratamento farmacológico , Citocinas/sangue , Óxido Nítrico/metabolismo , Modelos Animais de Doenças , Glutamato de Sódio , Glicemia/análiseRESUMO
Excessive extracellular matrix production by fibroblasts in response to tissue injury contributes to fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF). Epithelial-mesenchymal transition, involving transition of alveolar epithelial cells (AECs) to pulmonary fibroblasts, appears to be an important contributory process to lung fibrosis. Although aberrant expression of microRNAs (miRs) is involved in a variety of pathophysiologic processes, the role of miRs in fibrotic lung diseases is less well understood. In the present study, we found that miR-200a, miR-200b, and miR-200c are significantly down-regulated in the lungs of mice with experimental lung fibrosis. Levels of miR-200a and miR-200c were reduced in the lungs of patients with IPF. miR-200 had greater expression in AECs than in lung fibroblasts, and AECs from mice with experimental pulmonary fibrosis had diminished expression of miR-200. We found that the miR-200 family members inhibit transforming growth factor-ß1-induced epithelial-mesenchymal transition of AECs. miR-200 family members can reverse the fibrogenic activity of pulmonary fibroblasts from mice with experimental pulmonary fibrosis and from patients with IPF. Indeed, the introduction of miR-200c diminishes experimental pulmonary fibrosis in mice. Thus, the miR-200 family members participate importantly in fibrotic lung diseases and suggest that restoring miR-200 expression in the lungs may represent a novel therapeutic approach in treating pulmonary fibrotic diseases.
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Fibrose Pulmonar Idiopática/etiologia , MicroRNAs/fisiologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Células Cultivadas , Regulação para Baixo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Matriz Extracelular/fisiologia , Fibroblastos/metabolismo , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/prevenção & controle , Pulmão/metabolismo , Camundongos , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Alvéolos Pulmonares/metabolismo , Fator de Crescimento Transformador beta/farmacologiaRESUMO
High mobility group box 1 (HMGB1) is a highly conserved protein with multiple intracellular and extracellular functions, including transcriptional regulation, as well as modulation of inflammation, cell migration, and ingestion of apoptotic cells. In these experiments, we examined a potential role for intracellular HMGB1 in modulating phagocytosis. We found that phagocytosis of apoptotic cells resulted in translocation of HMGB1 into the cytoplasm and extracellular space. Transient or stable inhibition of HMGB1 expression in bone marrow-derived macrophages or fibroblasts resulted in increased phagocytosis of apoptotic thymocytes and apoptotic neutrophils. Knockdown of HMGB1 was associated with enhanced activation of Rac-1 and cytoskeletal rearrangement. Intracellular events involved in phagocytosis and upstream of Rac-1 activation, such as phosphorylation of ERK and focal adhesion kinase (FAK), were increased after knockdown of HMGB1. Inhibition of Src kinase activity prevented the increase in phosphorylation of FAK and ERK present during phagocytosis in HMGB1 knockdown cells, and also abrogated the enhancement in phagocytosis associated with HMGB1 knockdown. Interaction between Src and FAK in the cytoplasm of HMGB1 knockdown fibroblasts was enhanced compared with that present in control fibroblasts. Under in vitro conditions, the presence of HMGB1 diminished interactions between purified FAK and Src. These studies demonstrate a novel role for HMGB1 in the regulation of phagocytosis. In particular, these experiments show that intracellular HMGB1, through associating with Src kinase and inhibiting interactions between Src and FAK, diminishes the phagocytic ability of macrophages and other cell populations.
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Regulação para Baixo/imunologia , Proteína HMGB1/fisiologia , Líquido Intracelular/imunologia , Líquido Intracelular/metabolismo , Animais , Apoptose/genética , Apoptose/imunologia , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Linhagem Celular , Citofagocitose/genética , Citofagocitose/imunologia , Regulação para Baixo/genética , Fibroblastos/citologia , Fibroblastos/imunologia , Fibroblastos/metabolismo , Técnicas de Silenciamento de Genes , Células HEK293 , Proteína HMGB1/biossíntese , Proteína HMGB1/deficiência , Humanos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3RESUMO
Clearance of apoptotic cells by macrophages and other phagocytic cells, called efferocytosis, is a central process in the resolution of inflammation. Although the receptor for advanced glycation end products (RAGE) has been shown to participate in a variety of acute and chronic inflammatory processes in the lungs and other organs, a role for RAGE in efferocytosis has not been reported. In the present studies, we examined the potential involvement of RAGE in efferocytosis. Macrophages from transgenic RAGE(-/-) mice showed a decreased ability to engulf apoptotic neutrophils and thymocytes. Pretreatment of RAGE(+/+) macrophages with advanced glycation end products, which competitively bind to RAGE, or Abs against RAGE diminished phagocytosis of apoptotic cells. Overexpression of RAGE in human embryonic kidney 293 cells resulted in an increased ability to engulf apoptotic cells. Furthermore, we found that incubation with soluble RAGE enhances phagocytosis of apoptotic cells by both RAGE(+/+) and RAGE(-/-) macrophages. Direct binding of RAGE to phosphatidylserine (PS), an "eat me" signal highly expressed on apoptotic cells, was shown by using solid-phase ELISA. The ability of RAGE to bind to PS on apoptotic cells was confirmed in an adhesion assay. Decreased uptake of apoptotic neutrophils by macrophages was found under in vivo conditions in the lungs and peritoneal cavity of RAGE(-/-) mice. These results demonstrate a novel role for RAGE in which it is able to enhance efferocytosis through binding to PS on apoptotic cells.
Assuntos
Apoptose/imunologia , Macrófagos/imunologia , Fagócitos/imunologia , Receptores Imunológicos/imunologia , Animais , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/farmacologia , Células HEK293 , Humanos , Interleucina-10/imunologia , Interleucina-10/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Neutrófilos/metabolismo , Fagócitos/metabolismo , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Fosfatidilserinas/imunologia , Fosfatidilserinas/metabolismo , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Timo/citologia , Timo/imunologia , Timo/metabolismoRESUMO
This study emphasizes the importance of monitoring the microbiological quality of animal products, such as raw sheep's milk and cheese, to ensure food safety. In Brazil, there is currently no legislation governing the quality of sheep's milk and its derivatives. Therefore, this study aimed to evaluate: (i) the hygienic-sanitary quality of raw sheep's milk and cheese produced in southern Brazil; (ii) the presence of enterotoxins and Staphylococcus spp. in these products; and (iii) the susceptibility of the isolated Staphylococcus spp. to antimicrobial drugs and the presence of resistance genes. A total of 35 samples of sheep's milk and cheese were examined. The microbiological quality and presence of enterotoxins were accessed using Petrifilm and VIDAS SET2 methods, respectively. Antimicrobial susceptibility tests were conducted using VITEK 2 equipment and the disc diffusion method. The presence of resistance genes tet(L), sul1, sul2, ermB, tetM, AAC(6)', tetW, and strA were evaluated through PCR. In total, 39 Staphylococcus spp. were obtained. The resistance genes tetM, ermB, strA, tetL, sul1, AAC(6)', and sul2 were detected in 82%, 59%, 36%, 28%, 23%, 3%, and 3% of isolates, respectively. The findings revealed that both raw sheep's milk and cheese contained Staphylococcus spp. that exhibited resistance to antimicrobial drugs and harbored resistance genes. These results underscore the immediate need for specific legislation in Brazil to regulate the production and sale of these products.
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A large multi-institutional case series of laryngeal cancer (LC) T4a was carried out, including 134 cases treated with open partial horizontal laryngectomies (OPHL) +/- post-operative radiation therapy (PORT). The goal was to understand better whether OPHL can be included among the viable options in selected pT4a LC patients who refuse a standard approach, represented by total laryngectomy (TL) + PORT. All 134 patients underwent OPHL type I (supraglottic), II (supracricoid), or III (supratracheal), according to the European Laryngological Society Classification. Comparing clinical and pathological stages showed pT up-staging in 105 cases (78.4%) and pN up-staging in 19 patients (11.4%). Five-year data on overall survival, disease-specific survival, disease-free survival, freedom from laryngectomy, and laryngo-esophageal dysfunction-free survival (rate of patients surviving without a local recurrence or requiring total laryngectomy and without a feeding tube or a tracheostomy) were, respectively, 82.1%, 89.8%, 75.7%, 89.7%, and 78.3%. Overall, complications were observed in 22 cases (16.4%). Sequelae were observed in 28 patients (20.9%). No patients died during the postoperative period. This large series highlights the good onco-functional results of low-volume pT4a laryngeal tumors, with minimal or absent cartilage destruction, treated with OPHLs. The level of standardization of the indication for OPHL should allow consideration of OPHL as a valid therapeutic option in cases where the patient refuses total laryngectomy or non-surgical protocols with concomitant chemo-radiotherapy.
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The uptake and clearance of apoptotic cells by macrophages and other phagocytic cells, a process called efferocytosis, is a major component in the resolution of inflammation. Increased concentrations of extracellular histones are found during acute inflammatory states and appear to contribute to organ system dysfunction and mortality. In these studies, we examined the potential role of histones in modulating efferocytosis. We found that phagocytosis of apoptotic neutrophils or thymocytes by macrophages was significantly diminished in the presence of histones H3 or H4, but not histone H1. Histone H3 demonstrated direct binding to macrophages, an effect that was diminished by preincubation of macrophages with the opsonins growth arrest-specific gene 6 (Gas6) and milk fat globule-epidermal growth factor (EGF) 8 (MFG-E8). Incubation of histone H3 with soluble α(v)ß5 integrin and Mer, but not with α(v)ß3, diminished its binding to macrophages. Phagocytosis of apoptotic cells by alveolar macrophages in vivo was diminished in the presence of histone H3. Incubation of histone H3 with activated protein C, a treatment that degrades histones, abrogated its inhibitory effects on efferocytosis under both in vitro and in vivo conditions. The present studies demonstrate that histones have inhibitory effects on efferocytosis, suggesting a new mechanism by which extracellular histones contribute to acute inflammatory processes and tissue injury.
Assuntos
Histonas/metabolismo , Fagocitose/fisiologia , Animais , Antígenos de Superfície/metabolismo , Espaço Extracelular , Histonas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Cinética , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Leite/metabolismo , Proteínas Opsonizantes/metabolismo , Fagocitose/efeitos dos fármacos , Ligação Proteica , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Vitronectina/metabolismo , c-Mer Tirosina QuinaseRESUMO
INTRODUCTION: Tracheoesophageal puncture (TEP) with voice prosthesis (VP) is considered the gold standard in vocal rehabilitation of total laryngectomized patients, for generating better speech intelligibility and good vocal result. The aspects of aging that may be related to the success of this method of rehabilitation are rarely discussed in the literature. OBJECTIVE: To describe the factors that influence the rehabilitation outcome of the total laryngectomized older patients with voice prosthesis. METHODS: A retrospective cohort study enrolled in the Head and Neck Cancer Surgery Section of the Brazilian National Cancer Institute. Secondary data were collected through physical and electronic medical records of patients undergoing vocal rehabilitation using tracheoesophageal prosthesis, from 2006 to 2019. Descriptive analysis presented the distribution of the demographic and clinical characteristics of this population. RESULTS: Thirty patients rehabilitated with VP over 70 years old (mean age: 73.7 years), of which 93.3% were male. Married (73.3%), with low education (70%) and had a tumor of size T4a (60%). Adjuvant radiotherapy was performed in 66.7% of patients, 16.7% to previous radical radiotherapy, Complication rate was 53.3%, (68.7% granuloma and 18.7% shunt enlargement). All patients with shunt enlargement removed the prosthesis, whereas the prevalence of removal among those patients without complications was 14.3%. Logistic regression indicated that secondary TEP had 96% less chance of failure for phonation than primary TEP. CONCLUSIONS: Patients with more complications are more likely to have phonation issues and to remove the prosthesis. Older patients with larger tumors and who underwent salvage laryngectomy or were submitted to a primary puncture seem to be more likely to have complications and/or aphonia.
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AIMS: Sepsis is a potentially fatal systemic inflammatory response and its underlying pathophysiology is still poorly understood. Studies suggest that obesity, a component of metabolic syndrome (MS), is associated with sepsis survival. Therefore, this study focused on investigating the influence of MS on mortality and cardiovascular dysfunction induced by sublethal cecal ligation and puncture (SL-CLP). MAIN METHODS: Newborn Swiss mice received monosodium glutamate (MSG) (4 mg kg-1 day-1, s.c.) during the first 5 d of life for MS induction, while the control pups received equimolar saline solution. On the 75th day, SL-CLP was used to induce mild sepsis (M-CLP) in the MS (MS-M-CLP) and control (SAL-M-CLP) mice. The effect of MS on sepsis in mice was assessed by determining the survival rate and quantification of nitric oxide (NO) in the plasma, and associating this data with hematological and cardiovascular parameters. KEY FINDINGS: MS improved the survival of septic mice, preventing impairment to hematological and cardiovascular parameters. In addition, MS attenuated plasmatic NO increase, which is a typical feature of sepsis. SIGNIFICANCE: These findings provide new insights into the relationship between obesity and mild sepsis in mice, thus revealing an approach in favor of the "obesity paradox."
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Sistema Cardiovascular/fisiopatologia , Ceco/patologia , Síndrome Metabólica/fisiopatologia , Punções , Sepse/etiologia , Animais , Modelos Animais de Doenças , Ligadura , Camundongos , Óxido Nítrico/metabolismo , Análise de SobrevidaRESUMO
Innate immune responses against microorganisms may be mediated by Toll-like receptors (TLRs). Intestinal ischemia-reperfusion (i-I/R) leads to the translocation of bacteria and/or bacterial products such as endotoxin, which activate TLRs leading to acute intestinal and lung injury and inflammation observed upon gut trauma. Here, we investigated the role of TLR activation by using mice deficient for the common TLR adaptor protein myeloid differentiation factor 88 (MyD88) on local and remote inflammation following intestinal ischemia. Balb/c and MyD88(-/-) mice were subjected to occlusion of the superior mesenteric artery (45 min) followed by intestinal reperfusion (4 h). Acute neutrophil recruitment into the intestinal wall and the lung was significantly diminished in MyD88(-/-) after i-I/R, which was confirmed microscopically. Diminished neutrophil recruitment was accompanied with reduced concentration of TNF-alpha and IL-1beta level. Furthermore, diminished microvascular leak and bacteremia were associated with enhanced survival of MyD88(-/-) mice. However, neither TNF-alpha nor IL-1beta neutralization prevented neutrophil recruitment into the lung but attenuated intestinal inflammation upon i-I/R. In conclusion, our data demonstrate that disruption of the TLR/MyD88 pathway in mice attenuates acute intestinal and lung injury, inflammation, and endothelial damage allowing enhanced survival.
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Enteropatias/complicações , Enteropatias/patologia , Isquemia/complicações , Pneumopatias/patologia , Fator 88 de Diferenciação Mieloide/imunologia , Traumatismo por Reperfusão/complicações , Receptores Toll-Like/imunologia , Animais , Bacteriemia , Bactérias/imunologia , Toxinas Bacterianas/imunologia , Permeabilidade Capilar , Histocitoquímica , Interleucina-1beta/análise , Intestinos/patologia , Isquemia/patologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Microscopia , Fator 88 de Diferenciação Mieloide/deficiência , Neutrófilos/imunologia , Traumatismo por Reperfusão/patologia , Análise de Sobrevida , Fator de Necrose Tumoral alfa/análiseRESUMO
Since the successful use of the organoselenium drug ebselen in clinical trials for the treatment of neuropathological conditions associated with oxidative stress, there have been concerted efforts geared towards understanding the precise mechanism of action of ebselen and other organoselenium compounds, especially the diorganyl diselenides such as diphenyl diselenide, and its analogs. Although the mechanism of action of ebselen and other organoselenium compounds has been shown to be related to their ability to generally mimic native glutathione peroxidase (GPx), only ebselen however has been shown to serve as a substrate for the mammalian thioredoxin reductase (TrxR), demonstrating another component of its pharmacological mechanisms. In fact, there is a dearth of information on the ability of other organoselenium compounds, especially diphenyl diselenide and its analogs, to serve as substrates for the mammalian enzyme thioredoxin reductase. Interestingly, diphenyl diselenide shares several antioxidant and neuroprotective properties with ebselen. Hence in the present study, we tested the hypothesis that diphenyl diselenide and some of its analogs (4,4'-bistrifluoromethyldiphenyl diselenide, 4,4'-bismethoxy-diphenyl diselenide, 4.4'-biscarboxydiphenyl diselenide, 4,4'-bischlorodiphenyl diselenide, 2,4,6,2',4',6'-hexamethyldiphenyl diselenide) could also be substrates for rat hepatic TrxR. Here we show for the first time that diselenides are good substrates for mammalian TrxR, but not necessarily good mimetics of GPx, and vice versa. For instance, bis-methoxydiphenyl diselenide had no GPx activity, whereas it was a good substrate for reduction by TrxR. Our experimental observations indicate a possible dissociation between the two pathways for peroxide degradation (either via substrate for TrxR or as a mimic of GPx). Consequently, the antioxidant activity of diphenyl diselenide and analogs can be attributed to their capacity to be substrates for mammalian TrxR and we therefore conclude that subtle changes in the aryl moiety of diselenides can be used as tool for dissociation of GPx or TrxR pathways as mechanism triggering their antioxidant activities.
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Antioxidantes/metabolismo , Derivados de Benzeno/metabolismo , Glutationa Peroxidase/metabolismo , Mamíferos/metabolismo , Compostos Organosselênicos/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo , Animais , Estrutura Molecular , OxirreduçãoRESUMO
We hypothesized that long-term ethanol consumption would increase the mortality and aggravate the deleterious effects of sub-lethal cecal ligation and puncture (SL-CLP) in the vasculature by inducing the expression of inducible nitric oxide (NO) synthase (iNOS). Male C57BL/6J wild-type (WT) or iNOS-deficient mice (iNOS-/-) were treated with ethanol (20% v/v) for 12 weeks and then subjected to SL-CLP. Mice were killed 24â¯h post-operatively or followed six days for survival. Septic ethanol-treated mice showed a higher mortality than septic WT mice. However, septic iNOS-deficient mice treated with ethanol showed a decreased mortality rate when compared to ethanol-treated WT mice. Ethanol and SL-CLP augmented superoxide anion (O2-) generation in the mesenteric arterial bed (MAB) of both WT and iNOS-deficient mice. Treatment with ethanol and SL-CLP enhanced lipoperoxidation in the MAB of WT, but not iNOS-deficient mice. SL-CLP enhanced nitrate/nitrite (NOx) concentrations in the MAB of WT, but not iNOS-deficient mice. Both, ethanol and SL-CLP increased TNF-α and IL-6 levels in the MAB. Treatment with ethanol as well as SL-CLP up-regulated the expression of iNOS in the MAB of WT mice. The major finding of our study is that chronic ethanol consumption increases the mortality induced by SL-CLP and that iNOS plays a role in such response. Although ethanol led to vascular alterations, it did not aggravate the vascular injury induced by SL-CLP. Finally, iNOS mediated the increase in oxidative stress and pro-inflammatory cytokines induced by SL-CLP in the vasculature.
Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Consumo de Bebidas Alcoólicas/mortalidade , Etanol/efeitos adversos , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sepse/metabolismo , Sepse/patologia , Animais , Citocinas/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitratos/metabolismo , Nitritos/metabolismo , Superóxidos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
In this study, we tested the potential use of a lectin from Lonchocarpus sericeus seeds (LSL), to control neutrophil migration and inflammatory hypernociception (decrease of nociceptive threshold). Pretreatment of the animals intravenously (15 min before) with LSL inhibited neutrophil migration to the peritoneal cavity in a dose-dependent fashion confirmed by an inhibition of rolling and adhesion of leukocytes by intravital microscopy. We also tested the ability of the pretreatment with LSL to inhibit neutrophil migration on immunised mice, and it was observed that a strong inhibition of neutrophil migration induced by ovoalbumin in immunized mice. Another set of experiments showed that pretreatment of the animals with LSL, inhibited the mechanical hypernociception in mice induced by the i.pl. injection of OVA in immunized mice and of carrageenan in naïve mice, but not that induced by prostaglandin E(2) (PGE(2)) or formalin. This anti-nociceptive effect correlated with an effective blockade of neutrophil influx, as assessed by the hind paw tissue myeloperoxidase levels. In addition, we measured cytokines (TNF-alpha and IL-1beta) and chemokines (MIP-1alpha [CCL3] and KC [CXCL1]) from the peritoneal exudates and i.pl. tissue. Animals treated with LSL showed inhibition of cytokines and chemokines release in a dose-dependent manner. In conclusion, we demonstrated that the inhibitory effects of LSL on neutrophil migration and mechanical inflammatory hypernocicepetion are associated with the inhibition of the production of cytokines and chemokines.
Assuntos
Analgésicos/farmacologia , Neutrófilos/efeitos dos fármacos , Dor/tratamento farmacológico , Lectinas de Plantas/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Carragenina , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Citocinas/imunologia , Dinoprostona , Fabaceae/química , Formaldeído , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Ovalbumina/imunologia , Dor/induzido quimicamente , Dor/imunologia , Peroxidase/metabolismoRESUMO
Patients with chronic obstructive pulmonary disease (COPD) may have poor inspiratory muscle function, which reduces minute and alveolar ventilation, leading to increased hypoxemia and slow pulmonary oxygen uptake kinetics. However, little is known about the effect of inspiratory muscle weakness (IMW) on oxygen uptake kinetics in patients with COPD. Thus, we tested the hypothesis that COPD patients with IMW have slowed oxygen uptake kinetics. An observational study was conducted that included COPD patients with moderate to severe airflow limitation and a history of intolerance to exercise. Participants were divided into 2 groups: (IMW+; n = 22) (IMW-; n = 23) of muscle weakness. The maximal inspiratory, expiratory, and sustained inspiratory strength as well as the maximal endurance of the inspiratory muscles were lower in IMW+ patients (36 ± 9.5 cm H2O; 52 ± 14 cm H2O; 20 ± 6.5 cm H2O; 94 ± 84 s, respectively) than in IMW- patients (88 ± 12 cm H2O; 97 ± 28 cm H2O; 82.5 ± 54 cm H2O; 559 ± 92 s, respectively; p < 0.05). Moreover, the 6-min walk test and peak oxygen uptake were reduced in the IMW+ patients. During the constant work test, oxygen uptake kinetics were slowed in the IMW+ compared with IMW- patients (88 ± 29 vs 61 ± 18 s, p < 0.05). Our findings demonstrate that inspiratory muscle weakness in COPD is associated with slowed oxygen uptake kinetics, and thus, reduced functional capacity.
Assuntos
Debilidade Muscular/complicações , Consumo de Oxigênio , Doença Pulmonar Obstrutiva Crônica/metabolismo , Músculos Respiratórios , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenômenos Fisiológicos RespiratóriosRESUMO
A reduction of the neutrophil migration into the site of infection during cecal ligation and puncture-induced sepsis increases host mortality. Inhibition of heme oxygenase (HO) prevents this neutrophil paralysis and improves host survival in the cecal ligation and puncture model. Taking into account that almost 50% of all sepsis cases are a consequence of pneumonia, we designed the present study to determine the role of HO in an experimental model of pneumonia-induced sepsis. The objective of this study was to evaluate whether the inhibition of HO improves the outcome and pathophysiologic changes of sepsis induced by an intratracheal instillation of Klebsiella pneumoniae. The pretreatment of mice subjected to pneumonia-induced sepsis with ZnDPBG (zinc deuteroporphyrin 2,4-bis glycol), a nonspecific HO inhibitor, increased the number of neutrophils in the bronchoalveolar spaces, reduced the bacterial load at the site of infection, and prevented the upregulation of CD11b and the downregulation of CXCR2 on blood neutrophils. Moreover, the pretreatment with ZnDPBG decreased alveolar collapse, attenuating the deleterious changes in pulmonary mechanics and gas exchanges and, as a consequence, improved the survival rate of mice from 0% to â¼20%. These results show that heme oxygenase is involved in the pathophysiology of pneumonia-induced sepsis and suggest that HO inhibitors could be helpful for the management of this disease.
Assuntos
Bacteriemia/enzimologia , Heme Oxigenase (Desciclizante)/antagonistas & inibidores , Doenças do Sistema Imunitário/enzimologia , Infecções por Klebsiella/enzimologia , Transtornos Leucocíticos/enzimologia , Pneumonia Bacteriana/enzimologia , Alvéolos Pulmonares/enzimologia , Lesão Pulmonar Aguda/prevenção & controle , Animais , Bacteriemia/microbiologia , Brônquios/enzimologia , Quimiocinas/metabolismo , Creatina Quinase Forma MB/metabolismo , Citocinas/metabolismo , Deuteroporfirinas/farmacologia , Inibidores Enzimáticos/farmacologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae , Camundongos , Pneumonia Bacteriana/microbiologia , Receptores de Interleucina-8B/metabolismoRESUMO
The mechanisms underlying immune deficiency in diabetes are largely unknown. In the present study, we demonstrate that diabetic mice are highly susceptible to polymicrobial sepsis due to reduction in rolling, adhesion, and migration of leukocytes to the focus of infection. In addition, after sepsis induction, CXCR2 was strongly downregulated in neutrophils from diabetic mice compared with nondiabetic mice. Furthermore, CXCR2 downregulation was associated with increased G-protein-coupled receptor kinase 2 (GRK2) expression in these cells. Different from nondiabetic mice, diabetic animals submitted to mild sepsis displayed a significant augment in α1-acid glycoprotein (AGP) hepatic mRNA expression and serum protein levels. Administration of AGP in nondiabetic mice subjected to mild sepsis inhibited the neutrophil migration to the focus of infection, as well as induced l-selectin shedding and rise in CD11b of blood neutrophils. Insulin treatment of diabetic mice reduced mortality rate, prevented the failure of neutrophil migration, impaired GRK2-mediated CXCR2 downregulation, and decreased the generation of AGP. Finally, administration of AGP abolished the effect of insulin treatment in diabetic mice. Together, these data suggest that AGP may be involved in reduction of neutrophil migration and increased susceptibility to sepsis in diabetic mice.