RESUMO
Infection with the protozoan Trypanosoma cruzi causes Chagas disease and consequently leads to severe inflammatory heart condition; however, the mechanisms driving this inflammatory response have not been completely elucidated. Nitric oxide (NO) is a key mediator of parasite killing in T. cruzi-infected mice, and previous studies have suggested that leukotrienes (LTs) essentially regulate the NO activity in the heart. We used infected 5-lipoxygenase-deficient mice (5-LO-/-) to explore the participation of nitric oxide synthase isoforms, inducible (iNOS) and constitutive (cNOS), in heart injury, cytokine profile, and oxidative stress during the early stage of T. cruzi infection. Our evidence suggests that the cNOS of the host is involved in the resistance of 5-LO-/- mice during T. cruzi infection. iNOS inhibition generated a remarkable increase in T. cruzi infection in the blood and heart of mice, whereas cNOS inhibition reduced cardiac parasitism (amastigote nests). Furthermore, this inhibition associates with a higher IFN-γ production and lower lipid peroxidation status. These data provide a better understanding about the influence of NO-interfering therapies for the inflammatory response toward T. cruzi infection.
Assuntos
Araquidonato 5-Lipoxigenase/sangue , Doença de Chagas/sangue , Doença de Chagas/enzimologia , Animais , Antioxidantes/metabolismo , Citocinas/sangue , Camundongos , Camundongos Knockout , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/sangue , Trypanosoma cruzi/patogenicidadeRESUMO
Objective: To evaluate whether an animal model of mania induced by lisdexamfetamine dimesylate (LDX) has an inflammatory profile and whether immune activation by lipopolysaccharides (LPS) has a cumulative effect on subsequent stimuli in this model. We also evaluated the action of lithium (Li) on inflammatory and neurotrophic factors. Methods: Adult male Wistar rats were subjected to an animal model of mania. After the open-field test, they were given LPS to induce systemic immune activation. Subsequently, the animals' blood was collected, and their serum levels of brain-derived neurotrophic factor and inflammatory markers (tumor necrosis factor [TNF]-α, interleukin [IL]-6, IL-1β, IL-10, and inducible nitric oxide synthase [iNOS]) were measured. Results: LDX induced hyperactivity in the animals, but no inflammatory marker levels increased except brain-derived neurotrophic factor (BDNF). Li had no effect on serum BDNF levels but prevented iNOS levels from increasing in animals subjected to immune activation. Conclusion: Although Li prevented an LPS-induced increase in serum iNOS levels, its potential anti-inflammatory effects in this animal model of mania were conflicting.
Assuntos
Animais , Masculino , Transtorno Bipolar/imunologia , Modelos Animais de Doenças , Dimesilato de Lisdexanfetamina , Lítio/farmacologia , Anti-Inflamatórios/farmacologia , Fatores de Crescimento Neural/efeitos dos fármacos , Fatores de Tempo , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/induzido quimicamente , Ensaio de Imunoadsorção Enzimática , Lipopolissacarídeos/farmacologia , Reprodutibilidade dos Testes , Citocinas/sangue , Resultado do Tratamento , Ratos Wistar , Fator Neurotrófico Derivado do Encéfalo/sangue , Óxido Nítrico Sintase Tipo II/sangue , Locomoção/efeitos dos fármacosRESUMO
OBJECTIVE: To evaluate whether an animal model of mania induced by lisdexamfetamine dimesylate (LDX) has an inflammatory profile and whether immune activation by lipopolysaccharides (LPS) has a cumulative effect on subsequent stimuli in this model. We also evaluated the action of lithium (Li) on inflammatory and neurotrophic factors. METHODS: Adult male Wistar rats were subjected to an animal model of mania. After the open-field test, they were given LPS to induce systemic immune activation. Subsequently, the animals' blood was collected, and their serum levels of brain-derived neurotrophic factor and inflammatory markers (tumor necrosis factor [TNF]-α, interleukin [IL]-6, IL-1ß, IL-10, and inducible nitric oxide synthase [iNOS]) were measured. RESULTS: LDX induced hyperactivity in the animals, but no inflammatory marker levels increased except brain-derived neurotrophic factor (BDNF). Li had no effect on serum BDNF levels but prevented iNOS levels from increasing in animals subjected to immune activation. CONCLUSION: Although Li prevented an LPS-induced increase in serum iNOS levels, its potential anti-inflammatory effects in this animal model of mania were conflicting.
Assuntos
Anti-Inflamatórios/farmacologia , Transtorno Bipolar/imunologia , Modelos Animais de Doenças , Dimesilato de Lisdexanfetamina , Lítio/farmacologia , Fatores de Crescimento Neural/efeitos dos fármacos , Animais , Transtorno Bipolar/induzido quimicamente , Transtorno Bipolar/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Lipopolissacarídeos/farmacologia , Locomoção/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase Tipo II/sangue , Ratos Wistar , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do TratamentoRESUMO
Elderly organisms are more susceptible to infectious diseases. However, the impact of aging on antiparasitic mechanisms, especially the nitric oxide pathway, is poorly understood. Using an integrated in vivo and in vitro model, we compared the severity of Trypanosoma cruzi infection in young and elderly (8 or 72 weeks old) mice. Forty C57BL/6 mice were randomized into four groups: Y-inf, young infected; Yn-inf, young uninfected; A-inf, aged infected; An-inf, aged uninfected. Parasitemia was measured daily, and animals were euthanized after 15 days of infection. Trypanosoma cruzi-induced inflammatory processes were analyzed in blood and heart samples, as well as in bone marrow-derived macrophages (BMDMs) co-cultured with splenocytes isolated from young or elderly mice. Our results indicated upregulated IgG2b and IL-17 production in elderly animals, which was not sufficient to reduce parasitemia, parasitic load and myocarditis to levels observed in young animals. The higher susceptibility of elderly mice to T. cruzi infection was accompanied by reduced cardiac inducible nitric oxide synthase (iNOS) gene expression, nitric oxide (NO) and IFN-γ levels, as well as an antagonistic upregulation of arginase-1 expression and arginase activity. The same responses were observed when BMDMs co-cultured with splenocytes from elderly mice were stimulated with T. cruzi antigens. Our findings indicate that elderly mice were more susceptible to T. cruzi infection, which was potentially related to an attenuated response to antigenic stimulation, inhibition of iNOS gene expression and NO production, and antagonistic upregulation of arginase gene expression and activity, which created favorable conditions for heart parasitism and myocarditis development.
Assuntos
Envelhecimento/genética , Arginase/genética , Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Óxido Nítrico Sintase Tipo II/genética , Parasitemia/genética , Trypanosoma cruzi/patogenicidade , Envelhecimento/imunologia , Animais , Antígenos de Protozoários/farmacologia , Arginase/sangue , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Técnicas de Cocultura , Regulação da Expressão Gênica , Coração/parasitologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/genética , Interferon gama/sangue , Interferon gama/genética , Interleucina-10/sangue , Interleucina-10/genética , Interleucina-17/sangue , Interleucina-17/genética , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/sangue , Parasitemia/imunologia , Índice de Gravidade de Doença , Transdução de Sinais , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/parasitologia , Trypanosoma cruzi/imunologiaRESUMO
BACKGROUND: Brain death elicits microvascular dysfunction and inflammation, and thereby compromises lung viability for transplantation. As 17ß-estradiol was shown to be anti-inflammatory and vascular protective, we investigated its effects on lung injury after brain death in male rats. METHODS: Wistar rats were assigned to: sham-operation by trepanation only (SH, n = 7); brain death (BD, n = 7); administration of 17ß-estradiol (280 µg/kg, iv) at 60 minutes after brain death (BD-E2, n = 7). Experiments were performed 180 minutes thereafter. Histopathological changes in the lung were evaluated by histomorphometry. Gene expression of inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and endothelin-1 was measured by real-time polymerase chain reaction. Protein expression of NO synthases, endothelin-1, platelet endothelial cell adhesion molecule-1 (PECAM-1), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), BCL-2, and caspase 3 was assessed by immunohistochemistry. Cytokines were quantified by enzyme-linked immunosorbent assay. RESULTS: Treatment with 17ß-estradiol after brain death decreased lung edema and hemorrhage (p < 0.0001), and serum levels of cytokine-induced neutrophil chemoattractant-1 (CINC-1; p = 0.0020). iNOS (p < 0.0001) and VCAM-1 (p < 0.0001) also diminished at protein levels, while eNOS accumulated (p = 0.0002). However, gene expression of iNOS, eNOS, and endothelin-1 was comparable among groups, as was protein expression of endothelin-1, ICAM-1, BCL-2, and caspase 3. CONCLUSIONS: 17ß-Estradiol effectively reduces lung injury in brain-dead rats mainly due to its ability to regulate NO synthases. Thus, the drug may improve lung viability for transplantation.
Assuntos
Anti-Inflamatórios/farmacologia , Morte Encefálica/patologia , Estradiol/farmacologia , Lesão Pulmonar/prevenção & controle , Transplante de Pulmão , Animais , Quimiocina CXCL1/sangue , Hemorragia/patologia , Hemorragia/prevenção & controle , Pneumopatias/patologia , Pneumopatias/prevenção & controle , Lesão Pulmonar/patologia , Masculino , Óxido Nítrico Sintase Tipo II/sangue , Óxido Nítrico Sintase Tipo III/sangue , Edema Pulmonar/patologia , Edema Pulmonar/prevenção & controle , Ratos , Ratos Wistar , Molécula 1 de Adesão de Célula Vascular/sangueRESUMO
Oxidative stress plays a role in the pathophysiology of rheumatoid arthritis (RA). The aim of the present study was to verify the influence of metabolic syndrome (MetS) and disease-modifying antirheumatic drugs on nitrosative and oxidative biomarkers in patients with RA. A total of 177 patients with RA and 150 healthy volunteers participated in this study, which measured lipid hydroperoxides, advanced oxidation protein products (AOPP), nitric oxide metabolites (NOx), carbonyl protein, total radical-trapping antioxidant parameter (TRAP), uric acid (UA), and C-reactive protein (CRP). NOx and the NOx/TRAP ratio were significantly increased in RA, while no significant differences in lipid hydroperoxides, AOPP, UA, and TRAP levels were found between both groups. Treatment with leflunomide was associated with increased levels of carbonyl protein, and lowered levels in TRAP and UA, while the NOx/TRAP ratio further increased. NOx and the NOx/TRAP ratio were significantly higher in women than in men, while TRAP and UA were significantly lower in women. MetS was accompanied by increased AOPP and UA levels. RA was best predicted by increased NOx/TRAP ratio, CRP, and BMI. In conclusion, our data demonstrated that NOx and NOx/TRAP are strongly associated with RA physiopathology. Our findings suggest that inhibition of iNOS may become an interesting therapeutic approach for the treatment of RA. In addition, the presence of MetS and a decrease in levels of UA by leflunomide favor redox imbalance in RA patients. More studies are needed to evaluate the impact of antioxidant capacity reduction on RA progression.
Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Isoxazóis/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Ácido Úrico/sangue , Adolescente , Adulto , Produtos da Oxidação Avançada de Proteínas/sangue , Produtos da Oxidação Avançada de Proteínas/genética , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/complicações , Artrite Reumatoide/patologia , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Leflunomida , Peróxidos Lipídicos/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/complicações , Síndrome Metabólica/patologia , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/sangue , Óxido Nítrico Sintase Tipo II/genética , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica , Fatores Sexuais , Ácido Úrico/antagonistas & inibidoresRESUMO
PURPOSE: The aim of this study was to evaluate serum levels of inducible nitric oxide synthase (INOS), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidative status (TOS) in women with primary ovarian insufficiency (POI) and to compare them with healthy fertile women. We also examined the possible risk factors associated with POI. METHODS: This cross-sectional case control study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. The study population consisted of 44 women with POI (study group) and 36 healthy fertile women (control group). In all patients, serum levels of INOS, MPO, TAS, and TOS were determined. INOS and MPO levels were measured by enzyme-linked immunosorbent assay whereas colorimetric method was used for evaluating TAS and TOS levels. Age, body mass index (BMI), obstetric history, smoking status, family history, comorbidities, sonographic findings, complete blood count values, C-reactive protein and baseline hormone levels were also analyzed. Student's t-test or Mann-Whitney U test was used to compare continuous variables between the groups; categorical data were evaluated by using Pearson χ2 or Fisher exact test, when appropriate. Binary logistic regression method was used to identify risk factors for POI. RESULTS: We found significantly elevated levels of INOS (234.1±749.5 versus133.8±143.0; p=0.005), MPO (3,438.7±1,228.6 versus 2,481.9±1,230.1; p=0.001), and TOS (4.3±1.4 versus 3.6±1.4; p=0.02) in the sera of the study group when compared to the BMI-age matched control group. However, difference in serum levels of TAS were not significant between the 2 groups (1.7±0.2 versus 1.6±0.2; p=0.15). Logistic regression method demonstrated that BMI <25 kg/m2, nulliparity, family history of POI, smoking, and elevated serum levels of INOS, MPO, and TOS were independent risk factors for POI. CONCLUSION: We found an increase in INOS, MPO, and TOS in women with POI. These serum markers may be promising in early diagnosis of POI. Further large-scale studies are required to determine whether oxidative stress markers have a role in diagnosing POI.
Assuntos
Estresse Oxidativo , Insuficiência Ovariana Primária/metabolismo , Adulto , Biomarcadores , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Óxido Nítrico Sintase Tipo II/sangue , Peroxidase/sangue , Insuficiência Ovariana Primária/sangue , Medição de Risco , Fatores de RiscoRESUMO
PURPOSE: The aim of this study was to evaluate serum levels of inducible nitric oxide synthase (INOS), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidative status (TOS) in women with primary ovarian insufficiency (POI) and to compare them with healthy fertile women. We also examined the possible risk factors associated with POI.METHODS: This cross-sectional case control study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. The study population consisted of 44 women with POI (study group) and 36 healthy fertile women (control group). In all patients, serum levels of INOS, MPO, TAS, and TOS were determined. INOS and MPO levels were measured by enzyme-linked immunosorbent assay whereas colorimetric method was used for evaluating TAS and TOS levels. Age, body mass index (BMI), obstetric history, smoking status, family history, comorbidities, sonographic findings, complete blood count values, C-reactive protein and baseline hormone levels were also analyzed. Student's t-test or Mann-Whitney U test was used to compare continuous variables between the groups; categorical data were evaluated by using Pearson χ2 or Fisher exact test, when appropriate. Binary logistic regression method was used to identify risk factors for POI.RESULTS: We found significantly elevated levels of INOS (234.1±749.5 versus133.8±143.0; p=0.005), MPO (3,438.7±1,228.6 versus 2,481.9±1,230.1; p=0.001), and TOS (4.3±1.4 versus 3.6±1.4; p=0.02) in the sera of the study group when compared to the BMI-age matched control group. However, difference in serum levels of TAS were not significant between the 2 groups (1.7±0.2 versus 1.6±0.2; p=0.15). Logistic regression method demonstrated that BMI <25 kg/m2, nulliparity, family history of POI, smoking, and elevated serum levels of INOS, MPO, and TOS were independent risk factors for POI.CONCLUSION: We found an increase in INOS, MPO, and TOS in women with POI. These serum markers may be promising in early diagnosis of POI. Further large-scale studies are required to determine whether oxidative stress markers have a role in diagnosing POI.
OBJETIVO: Avaliar os níveis séricos da sintetase nítrica induzível (INOS), da mieloperoxidase (MPO), do estado antioxidante total (EAT) e do estado oxidante total (EOT) em mulheres portadoras de insuficiência ovariana primária (IOP) e compará-las às mulheres férteis. Também examinamos os possíveis fatores de risco associados à IOP.MÉTODOS: Trata-se de estudo transversal caso-controle desenvolvido no Zekai Tahir Burak Women's Health Education and Research Hospital. A população de estudo abrangeu 44 mulheres portadoras de IOP (grupo de estudo) e 36 mulheres férteis hígidas (grupo controle). Em todas as pacientes, foram determinados os níveis séricos de INOS, MPO, EAT e EOT.Os níveis de INOS e MPO foram determinados com o uso do teste ELISA e os níveis de EAT e EOT foram determinados mediante método colorimétrico. Analisou-se também a idade, o índice de massa corporal (IMC), os antecedentes obstétricos, tabagismo, histórico familiar, comorbidades, achados sonográficos, valores completos do hemograma, proteína C-reativa e níveis hormonais basais. O teste t de Student ou o teste U de Mann-Whitney foi utilizado para comparar as variáveis contínuas entre os grupos; os dados categóricos foram avaliados pelo teste do χ2 de Pearson ou o teste exato de Fisher, conforme o caso. O método de regressão logística binária foi utilizado para identificar os fatores de risco para IOP.RESULTADOS: Encontramos níveis significativamente elevados de INOS (234,1±749,5 versus133,8±143,0; p=0,005), MPO (3.438,7±1.228,6 versus 2.481,9±1.230,1; p=0,001) e EOT (4,3±1,4 versus 3,6±1,4; p=0,02) nos soros do grupo estudo em relação ao grupo controle pareado por IMC e idade. Entretanto, as diferenças entre os níveis séricos de EAT nos dois grupos não foram significantes (1,7±0,2 versus 1,6±0,2; p=0,15). O método de regressão logística demonstrou que IMC <25 kg/m2, nuliparidade, histórico familiar de IOP, tabagismo e níveis séricos elevados de INOS, MPO e EOT foram fatores de risco independentes para IOP.CONCLUSÃO: Foram encontrados níveis aumentados de INOS, MPO e EOT em mulheres portadoras de IOP. Estes marcadores séricos podem ser promissores para o diagnóstico precoce de IOP. Novos estudos em larga escala são necessários para determinar se os marcadores de estresse oxidativo desempenham um papel no diagnóstico da IOP.
Assuntos
Humanos , Feminino , Adulto , Estresse Oxidativo , Insuficiência Ovariana Primária/metabolismo , Biomarcadores , Estudos de Casos e Controles , Estudos Transversais , Óxido Nítrico Sintase Tipo II/sangue , Peroxidase/sangue , Insuficiência Ovariana Primária/sangue , Medição de Risco , Fatores de RiscoRESUMO
We investigated whether physical exercise can affect platelet L-arginine - nitric oxide pathway in spontaneously hypertensive rats (SHR). Sixteen male SHR and 16 Wistar Kyoto rats (WKY) were divided among exercise (EX) and sedentary (SED) groups. After 20 weeks of treadmill training, systolic blood pressure (mm Hg) was significantly lower in exercised spontaneously hypertensive rats (SHR/EX; 138 ± 8) than in sedentary spontaneously hypertensive rats (SHR/SED; 214 ± 9). Exercise significantly increased platelet L-arginine transport (pmol L-arginine·(10(9) cells)(-1)·min(-1)), assessed by incubation with L-[(3)H]-arginine, in both WKY (SED, 0.196 ± 0.054 compared with EX, 0.531 ± 0.052) and SHR (SED, 0.346 ± 0.076 compared with EX, 0.600 ± 0.049). Nitric oxide synthase (NOS) activity (pmol L-citrulline·(10(8) cells)(-1)), measured by the conversion of L-[(3)H]-arginine to L-[(3)H]-citrulline, was significantly increased in SHR/EX (0.072 ± 0.007) compared with SHR/SED (0.038 ± 0.007), but no changes were observed in WKY. The iNOS and eNOS protein levels assessed by Western blot were not affected by exercise. This upregulation of the platelet L-arginine-NO pathway may attenuate the risk of thromboembolic events, supporting the role of exercise in hypertension management.
Assuntos
Arginina/sangue , Plaquetas/metabolismo , Hipertensão/metabolismo , Óxido Nítrico/sangue , Condicionamento Físico Animal/fisiologia , Animais , Pressão Sanguínea/fisiologia , Hipertensão/sangue , Hipertensão/fisiopatologia , Masculino , Óxido Nítrico Sintase Tipo II/sangue , Óxido Nítrico Sintase Tipo III/sangue , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transdução de Sinais/fisiologia , Regulação para CimaRESUMO
Nitric oxide (NO) production occurs through oxidation of the amino acid L-arginine by NO synthase (NOS). NO inhibits platelet activation by increasing the levels of cyclic guanosine monophosphate (cGMP), thus maintaining vascular homeostasis. Our group previously demonstrated (da Silva et al. 2005) an enhancement of the L-arginine-NO-cGMP pathway in platelets taken from chronic renal failure (CRF) patients on haemodialysis associated with reduced platelet aggregation. We investigate the platelet L-arginine-NO-cGMP pathway, platelet function, and inflammation from patients in CRF on conservative treatment. A total of 42 CRF patients and 42 controls (creatinine clearance = 27 ± 3 vs. 93 ± 1 mL per min per 1.73 m2, respectively) participated in this study. NOS activity and expression and cGMP concentration were measured in platelets. Platelet aggregation induced by collagen or ADP was evaluated and plasma levels of fibrinogen were determined by the Clauss method. A marked increase in basal NOS activity was seen in undialysed CRF patients compared with controls, accompanied by an elevation of fibrinogen plasma levels. There were no differences in expression of NOS and in cGMP levels. In this context, platelet aggregation was not affected. We provide the first evidence of increased intraplatelet NO biosynthesis in undialysed CRF patients, which can be an early marker of future haemostatic abnormalities during dialysis treatment.