RESUMO

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.

Assuntos

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/análise

RESUMO

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.

Assuntos

Transtornos de Deglutição , Laringectomia , Gravação em Vídeo , Humanos , Masculino , Laringectomia/efeitos adversos , Laringectomia/métodos , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/etiologia , Fluoroscopia/métodos , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Projetos Piloto , Neoplasias Laríngeas/cirurgia , Neoplasias Laríngeas/fisiopatologia , Deglutição/fisiologia , Faringe/fisiopatologia , Faringe/diagnóstico por imagem

RESUMO

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.

RESUMO

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."

Assuntos

Sistema Cardiovascular/fisiopatologia , Ceco/patologia , Síndrome Metabólica/fisiopatologia , Punções , Sepse/etiologia , Animais , Modelos Animais de Doenças , Ligadura , Camundongos , Óxido Nítrico/metabolismo , Análise de Sobrevida

RESUMO

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.

Assuntos

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 fármacos

RESUMO

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 24 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 fármacos

RESUMO

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 Respiratórios

RESUMO

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/farmacologia

RESUMO

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 ∼20%. 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/metabolismo

RESUMO

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.

Assuntos

Movimento Celular/imunologia , Diabetes Mellitus Experimental/metabolismo , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Orosomucoide/metabolismo , Sepse/metabolismo , Animais , Antígeno CD11b/metabolismo , Movimento Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/imunologia , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/metabolismo , Insulina/farmacologia , Insulina/uso terapêutico , Selectina L/metabolismo , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Sepse/imunologia

RESUMO

Thioredoxin reductase (TrxR) isoforms play important roles in cell physiology, protecting cells against oxidative processes. In addition to its endogenous substrates (Trx isoforms), hepatic TrxR can reduce organic selenium compounds such as ebselen and diphenyl diselenide to their selenol intermediates, which can be involved in their hepatoprotective properties. Taking this into account, the aim of the present study was to evaluate the hypothesis that ebselen, diphenyl diselenide and its analogs (4,4'-bistrifluoromethyldiphenyl diselenide, 4,4'-bismethoxydiphenyl diselenide, 4.4'-biscarboxy-diphenyl diselenide, 4,4'-bischlorodiphenyl diselenide, 2,4,6,2',4',6'-hexamethyldiphenyl diselenide) could be substrates of rat brain TrxR. In the presence of partially purified rat brain TrxR, diphenyl diselenide, bismethoxydiphenyl diselenide and bischlorodiphenyl diselenide (at 10, 15 and 20µM) stimulated NADPH oxidation, indicating that they are substrates of brain TrxR. In contrast, ebselen and bistrifluoromethyldiphenyl diselenide, that have been previously demonstrated to be substrate of hepatic TrxR, were not reduced by rat brain TrxR. The results presented here suggest that diphenyl diselenide can exert neuroprotective effects by mimicking glutathione peroxidase activity and also via its reduction by TrxR. However, ebselen was not reduced by brain TrxR, indicating that the neuroprotective properties of this compound is possibly mediate by its glutathione peroxidase-like activity.

Assuntos

Derivados de Benzeno/farmacologia , Córtex Cerebral/enzimologia , Fármacos Neuroprotetores/farmacologia , Compostos Organosselênicos/farmacologia , Tiorredoxina Dissulfeto Redutase/metabolismo , Análise de Variância , Animais , Azóis/metabolismo , Derivados de Benzeno/química , Córtex Cerebral/efeitos dos fármacos , Glutationa Peroxidase , Isoindóis , Modelos Biológicos , Fármacos Neuroprotetores/química , Compostos Organosselênicos/química , Compostos Organosselênicos/metabolismo , Oxirredução/efeitos dos fármacos , Ratos , Especificidade por Substrato/efeitos dos fármacos

RESUMO

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.

Assuntos

Antioxidantes/metabolismo , Derivados de Benzeno/metabolismo , Glutationa Peroxidase/metabolismo , Mamíferos/metabolismo , Compostos Organosselênicos/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo , Animais , Estrutura Molecular , Oxirredução

RESUMO

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.

Assuntos

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/análise

RESUMO

Oxidative stress has been pointed out as an important molecular mechanism in methylmercury (MeHg) intoxication. At low doses, diphenyl diselenide ((PhSe)2), a structurally simple organoselenium compound, has been shown to possess antioxidant and neuroprotective properties. Here we have examined the possible in vivo protective effect of diphenyl diselenide against the potential pro-oxidative effects of MeHg in mouse liver, kidney, cerebrum and cerebellum. The effects of MeHg exposure (2 mg/(kg day) of methylmercury chloride 10 ml/kg, p.o.), as well as the possible antagonist effect of diphenyl diselenide (1 and 0.4 mg/(kg day); s.c.) on body weight gain and on hepatic, cerebellar, cerebral and renal levels of thiobarbituric acid reactive substances (TBARS), non-protein thiols (NPSH), ascorbic acid content, mercury concentrations and activities of antioxidant enzymes (glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD)) were evaluated after 35 days of treatment. MeHg caused an increase in TBARS and decreased NPSH levels in all tissues. MeHg also induced a decrease in hepatic ascorbic acid content and in renal GPx and CAT activities. Diphenyl diselenide (1 mg/kg) conferred protection against MeHg-induced hepatic and renal lipid peroxidation and at both doses prevented the reduction in hepatic NPSH levels. Diphenyl diselenide also conferred a partial protection against MeHg-induced oxidative stress (TBARS and NPSH) in liver and cerebellum. Of particular importance, diphenyl diselenide decreased the deposition of Hg in cerebrum, cerebellum, kidney and liver. The present results indicate that diphenyl diselenide can protect against some toxic effects of MeHg in mice. This protection may be related to its antioxidant properties and its ability to reduce Hg body burden. We posit that formation of a selenol intermediate, which possesses high nucleophilicity and high affinity for MeHg, accounts for the ability of diphenyl diselenide to ameliorate MeHg-induced toxicity.

Assuntos

Derivados de Benzeno/farmacologia , Encéfalo/metabolismo , Rim/metabolismo , Fígado/metabolismo , Mercúrio/metabolismo , Compostos de Metilmercúrio/toxicidade , Compostos Organosselênicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Fármacos Neuroprotetores/farmacologia , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Aumento de Peso/efeitos dos fármacos

RESUMO

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/metabolismo

RESUMO

OBJECTIVE: We have documented an impaired neutrophil migration toward the infectious focus in severe sepsis. This phenomenon appears to be mediated by nitric oxide, the release of which is stimulated by circulating inflammatory cytokines released by immune cells after stimulation by bacteria and/or their products. Toll-like receptor 4 (TLR4) is the major recognition receptor for lipopolysaccharide, a component of Gram-negative bacterial cell walls. In the present study, we investigated whether TLR4 is involved in the failure of neutrophil migration in mice subjected to polymicrobial or Gram-negative sepsis. DESIGN: Controlled animal study. SETTING: University research laboratory. SUBJECTS: Male C3H/HeJ (TLR4-deficient) and C3H/HePas (TLR4-normal) mice. INTERVENTIONS: Mice were subjected to sublethal or lethal polymicrobial sepsis, both induced by cecal ligation and puncture or intraperitoneal polymicrobial inoculation, and subjected to sublethal Gram-negative sepsis induced by intraperitoneal Salmonella typhimurium inoculation (GNI). Survival was monitored for 5 days. In separate experiments, mice were killed 6 hrs after sepsis induction, and intraperitoneal neutrophil migration, bacteremia, lung neutrophil sequestration, and levels of cytokines, chemokines, and nitrate were evaluated. MEASUREMENTS AND RESULTS: TLR4-deficient (C3H/HeJ) mice presented incapacity to promote neutrophil recruitment to the infectious site after sublethal GNI, resulting in high mortality. However, TLR4 signaling is not essential to display neutrophil migration in sublethal polymicrobial sepsis induced by both cecal ligation and puncture and polymicrobial inoculation models, but surprisingly, it is crucial to establish the impairment of neutrophil migration in lethal polymicrobial sepsis, since TLR4-deficient mice that underwent lethal cecal ligation and puncture or polymicrobial inoculation did not present failure of neutrophil migration to infectious focus. As a consequence, these animals presented low bacteremia and a high survival rate and did not display systemic inflammation, determined by high levels of circulating cytokines and lung neutrophil sequestration and chemokine production. CONCLUSION: These results highlight the harmful role of TLR4 signaling in polymicrobial severe sepsis.

Assuntos

Neutrófilos/fisiologia , Óxido Nítrico/fisiologia , Sepse/fisiopatologia , Receptor 4 Toll-Like/fisiologia , Animais , Movimento Celular , Masculino , Camundongos , Neutrófilos/metabolismo , Fagocitose , Receptor 4 Toll-Like/deficiência

RESUMO

A auto-imunidade se manifesta quando ocorre uma falha nos mecanismos de auto-tolerância responsáveis pela discriminação entre o próprio e o não próprio, desencadeando uma resposta imune adaptativa específica contra os auto-antígenos. A doença de Graves (DG), uma doença auto-imune associada com atividade excessiva da tireóide, podendo vir associada a outras doenças auto-imunes endócrinas, como Diabetes mellitus tipo 1, e não endócrinas como Lupus Eritematoso Sistêmico (LES) ou Artrite Reumatóide (AR). As doenças auto-imunes são caracterizadas pela etiologia multifatorial, onde fatores genéticos, endócrinos, imunológicos, infecciosos, ambientais e emocionais contribuem para o desencadeamento e agravamento dos processos lesivos. Tem-se pesquisado cada vez mais a influência de fatores genéticos sobre o desenvolvimento de doenças auto-imunes e é neste contexto que se observa a forte associação do HLA-DR, tanto com DG como com AR. O presente trabalho tem como objetivo descrever as alterações laboratoriais observadas em uma paciente do sexo feminino, 22 anos, branca, com o diagnóstico das duas doenças auto-imunes de evolução crônica, a DG e AR, correlacionar os resultados laboratoriais com os sinais e sintomas clínicos apresentados e avaliar os exames laboratoriais realizados para o monitoramento clínico e terapêutico.

Assuntos

Humanos , Feminino , Adulto , Antígenos HLA-DR/análise , Artrite Reumatoide , Doença de Graves/diagnóstico , Doenças Autoimunes , Técnicas de Laboratório Clínico , Hipertireoidismo