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1.
Eur J Pharmacol ; 956: 175932, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37536622

RESUMO

Graft-versus-host disease (GVHD) is a serious inflammatory illness that often occurs as a secondary complication of bone marrow transplantation. Current therapies have limited effectiveness and fail to achieve a balance between inflammation and the graft-versus-tumor effect. In this study, we investigate the effects of the endocannabinoid anandamide on the complex pathology of GVHD. We assess the effects of an irreversible inhibitor of fatty acid amine hydrolase or exogenous anandamide and find that they increase survival and reduce clinical signs in GVHD mice. In the intestine of GVHD mice, treatment with exogenous anandamide also leads to a reduction in the number of CD3+, CD3+CD4+, and CD3+CD8+ cells, which reduces the activation of CD3+CD4+ and CD3+CD8+ cells, as assessed by enhanced CD28 expression, a T cell co-stimulatory molecule. Exogenous AEA was also able to reduce TNF-α and increase IL-10 in the intestine of GVHD mice. In the liver, exogenous AEA reduces injury, TNF-α levels, and the number of CD3+CD8+ cells. Interestingly, anandamide reduces Mac-1α, which lowers the adhesion of transplanted cells in mesenteric veins. These effects are mimicked by JWH133-a CB2 selective agonist-and abolished by treatment with a CB2 antagonist. Furthermore, the effects caused by anandamide treatment on survival were related to the CB2 receptor, as the CB2 antagonist abolished it. This study shows the critical role of the CB2 receptor in the modulation of the inflammatory response of GVHD by treatment with anandamide, the most prominent endocannabinoid.


Assuntos
Endocanabinoides , Doença Enxerto-Hospedeiro , Animais , Camundongos , Endocanabinoides/farmacologia , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/prevenção & controle , Intestinos , Linfócitos/metabolismo , Alcamidas Poli-Insaturadas/farmacologia , Receptor CB1 de Canabinoide , Receptor CB2 de Canabinoide , Fator de Necrose Tumoral alfa
2.
Cytokine ; 166: 156192, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37054665

RESUMO

AIMS: The consumption of highly refined carbohydrates increases systemic inflammatory markers, but its potential to exert direct myocardial inflammation is uncertain. Herein, we addressed the impact of a high-refined carbohydrate (HC) diet on mice heart and local inflammation over time. MAIN METHODS: BALB/c mice were fed with a standard chow (control) or an isocaloric HC diet for 2, 4, or 8 weeks (HC groups), in which the morphometry of heart sections and contractile analyses by invasive catheterization and Langendorff-perfused hearts were assessed. Cytokines levels by ELISA, matrix metalloproteinase (MMP) activity by zymography, in situ reactive oxygen species (ROS) staining and lipid peroxidation-induced TBARS levels, were also determined. KEY FINDINGS: HC diet fed mice displayed left ventricular hypertrophy and interstitial fibrosis in all times analyzed, which was confirmed by echocardiographic analyses of 8HC group. Impaired contractility indices of HC groups were observed by left ventricular catheterization, whereas ex vivo and in vitro indices of contraction under isoprenaline-stimulation were higher in HC-fed mice compared with controls. Peak levels of TNF-α, TGF-ß, ROS, TBARS, and MMP-2 occur independently of HC diet time. However, a long-lasting local reduction of the anti-inflammatory cytokine IL-10 was found, which was linearly correlated to the decline of systolic function in vivo. SIGNIFICANCE: Altogether, the results indicate that short-term consumption of HC diet negatively impacts the balance of anti-inflammatory defenses and proinflammatory/profibrotic mediators in the heart, which can contribute to HC diet-induced morphofunctional cardiac alterations.


Assuntos
Tecido Adiposo , Citocinas , Animais , Camundongos , Carboidratos da Dieta , Espécies Reativas de Oxigênio , Substâncias Reativas com Ácido Tiobarbitúrico , Dieta , Inflamação
3.
Peptides ; 157: 170863, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36028074

RESUMO

Vascular dysfunction induced by angiotensin-II can result from direct effects on vascular and inflammatory cells and indirect hemodynamic effects. Using isolated and functional cultured aortas, we aimed to identify the effects of angiotensin-II on cyclooxygenase (COX) and inducible nitric oxide synthase (iNOS) and evaluate their impact on vascular reactivity. Aortic rings from mice were incubated overnight in culture medium containing angiotensin-II (100 nmol/L) or vehicle to induce vascular disfunction. Vascular reactivity of cultured arteries was evaluated in a bath chamber. Immunofluorescence staining for COX-1 and COX-2 was performed. Nitric oxide (NO) formation was approached by the levels of nitrite, a NO end product, and using a fluorescent probe (DAF). Oxidative and nitrosative stress were determined by DHE fluorescence and nitrotyrosine staining, respectively. Arteries cultured with angiotensin-II showed impairment of endothelium-dependent relaxation, which was reversed by the AT1 receptor antagonist. Inhibition of COX and iNOS restored vascular relaxation, suggesting a common pathway in which angiotensin-II triggers COX and iNOS, leading to vasoconstrictor receptors activation. Moreover, using selective antagonists, TP and EP were identified as the receptors involved in this response. Endothelium-dependent contractions of angiotensin-II-cultured aortas were blunted by ibuprofen, and increased COX-2 immunostaining was found in the arteries, indicating endothelium release of vasoconstrictor prostanoids. Angiotensin-II induced increased reactive oxygen species and NO production. An iNOS inhibitor prevented NO enhancement and nitrotyrosine accumulation in arteries stimulated with angiotensin-II. These results confirm that angiotensin-II causes vascular inflammation that culminates in endothelial dysfunction in an iNOS and COX codependent manner.


Assuntos
Angiotensina II , Óxido Nítrico , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Ciclo-Oxigenase 2 , Endotélio Vascular , Corantes Fluorescentes/farmacologia , Ibuprofeno/farmacologia , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/metabolismo , Nitritos/farmacologia , Prostaglandinas , Espécies Reativas de Oxigênio/metabolismo , Vasoconstritores/farmacologia
4.
FASEB J ; 35(10): e21901, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34569665

RESUMO

Chagasic cardiomyopathy (CCC) is one of the main causes of heart failure and sudden death in Latin America. To date, there is no available medication to prevent or reverse the onset of cardiac symptoms. CCC occurs in a scenario of disrupted calcium dynamics and enhanced oxidative stress, which combined, may favor the hyper activation of calcium/calmodulin (Ca2+ /CaM)-calcium/calmodulin-dependent protein kinase II (CaMKII) (Ca2+ /CaM-CaMKII) pathway, which is fundamental for heart physiology and it is implicated in other cardiac diseases. Here, we evaluated the association between Ca2+ /CaM-CaMKII in the electro-mechanical (dys)function of the heart in the early stage of chronic experimental Trypanosoma cruzi infection. We observed that in vitro and ex vivo inhibition of Ca2+ /CaM-CaMKII reversed the arrhythmic profile of isolated hearts and isolated left-ventricles cardiomyocytes. The benefits of the limited Ca2+ /CaM-CaMKII activation to cardiomyocytes' electrical properties are partially related to the restoration of Ca2+ dynamics in a damaged cellular environment created after T. cruzi infection. Moreover, Ca2+ /CaM-CaMKII inhibition prevented the onset of arrhythmic contractions on isolated heart preparations of chagasic mice and restored the responsiveness to the increase in the left-ventricle pre-load. Taken together, our data provide the first experimental evidence for the potential of targeting Ca2+ /CaM-CaMKII pathway as a novel therapeutic target to treat CCC.


Assuntos
Arritmias Cardíacas/metabolismo , Sinalização do Cálcio , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cálcio/metabolismo , Calmodulina/metabolismo , Cardiomiopatia Chagásica/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Arritmias Cardíacas/parasitologia , Cardiomiopatia Chagásica/parasitologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos BALB C
5.
J Pharmacol Exp Ther ; 377(2): 273-283, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33658314

RESUMO

Cannabidiol (CBD) is a highly lipidic phytocannabinoid with remarkable anti-inflammatory effects. The aim of this study was to evaluate CBD's effects and mechanisms of action in the treatment of mice subjected to acute graft-versus-host disease (aGVHD). aGVHD was induced by the transplantation of bone marrow cells and splenocytes from C57BL-6j to Balb-c mice. The recipient mice were treated daily with CBD, and the treatment reduced mouse mortality by decreasing inflammation and injury and promoting immune regulation in the jejunum, ileum, and liver. Analysis of the jejunum and ileum showed that CBD treatment reduced the levels of C-C motif chemokine ligand (CCL) 2, CCL3, CCL5, tumor necrosis factor α, and interferon γ (IFNγ). CCL3 and IFNγ levels were also decreased in the liver. Mechanistically, CBD also increased the number of cannabinoid receptor type 2 (CB2) receptors on CD4+ and forkhead box P3+ cells in the intestine, which may explain the reduction in proinflammatory cytokines and chemokines. Antagonists of the CB2 receptor reduced the survival rates of CBD-treated mice, suggesting the participation of this receptor in the effects of CBD. Furthermore, treatment with CBD did not interfere with the graft-versus-leukemia response. CBD treatment appears to protect aGVHD mice by anti-inflammatory and immunomodulatory effects partially mediated by CB2 receptor interaction. Altogether, our study suggests that CBD represents an interesting approach in the treatment of aGVHD, with potential therapeutic applications in patients undergoing bone marrow transplantation. SIGNIFICANCE STATEMENT: This study provides for the first time a mechanism by which cannabidiol, a phytocannabinoid with no psychoactive effect, induces immunomodulation in the graft-versus-host disease. Enhancing intestinal cannabinoid receptor type 2 (CB2) receptor expression on CD4+ and forkhead box P3+ cells and increasing the number of these regulatory cells, cannabidiol decreases proinflammatory cytokines and increases graft-versus-host disease mice survival. This effect is dependent of CB2 receptor activation. Besides, cannabidiol did not interfere with graft-versus-leukemia response, a central response to avoid primary disease relapse.


Assuntos
Canabidiol/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Mucosa Intestinal/metabolismo , Leucemia/terapia , Receptor CB2 de Canabinoide/metabolismo , Animais , Transplante de Medula Óssea/efeitos adversos , Transplante de Medula Óssea/métodos , Canabidiol/farmacologia , Células Cultivadas , Quimiocinas CC/genética , Quimiocinas CC/metabolismo , Interferon gama/genética , Interferon gama/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Leucemia/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/genética , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
6.
Br J Pharmacol ; 176(12): 2028-2048, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29969833

RESUMO

Arterial hypertension represents a serious public health problem, being a major cause of morbidity and mortality worldwide. The availability of many antihypertensive therapeutic strategies still fails to adequately treat around 20% of hypertensive patients, who are considered resistant to conventional treatment. In the pathogenesis of hypertension, immune system mechanisms are activated and both the innate and adaptive immune responses play a crucial role. However, what, when and how the immune system is triggered during hypertension development is still largely undefined. In this context, this review highlights scientific advances in the manipulation of the immune system in order to attenuate hypertension and end-organ damage. Here, we discuss the potential use of immunosuppressants and immunomodulators as pharmacological tools to control the activation of the immune system, by non-specific and specific mechanisms, to treat hypertension and improve end-organ damage. Nevertheless, more clinical trials should be performed with these drugs to establish their therapeutic efficacy, safety and risk-benefit ratio in hypertensive conditions. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.


Assuntos
Anti-Hipertensivos/farmacologia , Hipertensão/tratamento farmacológico , Sistema Imunitário/efeitos dos fármacos , Animais , Humanos , Hipertensão/imunologia , Sistema Imunitário/imunologia
7.
Estud. interdiscip. envelhec ; 21(1): 35-54, abr. 2016. tab
Artigo em Português | LILACS | ID: biblio-868959

RESUMO

O envelhecimento da população brasileira trouxe mudanças em seu perfil epidemiológico, como o aumento da ocorrência de doenças crônicas e incapacidades funcionais, além de maior demanda por serviços de saúde, representando um desafio para a Saúde Coletiva no conhecimento das suas especificidades. Nesse sentido, idosos do Programa de Assistência ao Idoso do SESC Minas, na cidade de Governador Valadares (MG), responderam a um questionário semi estruturado para variáveis socioeconômicas, condições de saúde e hábitos de vida a fim de se traçar um diagnóstico desta população e direcionar ações interdisciplinares educativas e preventivas como incentivo ao envelhecimento ativo. Os dados revelaram as principais doenças: hipertensão arterial (63,8%), osteoartrite (25,5%), cardiopatias (17%) e diabetes (10,6%). A poli farmácia foi identificada em 29,8% dos idosos, incluindo o uso de medicamentos alopáticos, fitoterápicos e plantas medicinais. Doze idosos (25,5%) relataram possuir lesões de pele, 72,3% informaram uso de próteses dentárias e 2,1% próteses ortopédicas. A maioria dos idosos classificou sua alimentação como saudável (85,1%), mas todos relataram algum tipo de perda funcional. Os resultados demonstram que o Programa Assistencial conta com idosos com o perfil de saúde semelhante ao da população idosa brasileira, com ampla ocorrência de doenças crônicas, edentulismo, incapacidades funcionais e elevado consumo de medicamentos. O presente estudo reforça a importância do trabalho interdisciplinar como subsídio para o desenvolvimento de intervenções mais sensíveis e eficazes, considerando a perspectiva do próprio indivíduo e suas necessidades.


The aging of the Brazilian population brought changes in their epidemiological profile: increased occurrence of chronic illnesses and functional disabilities; increased demand for health services. The knowledge of the characteristics and elements of such changes have represented a challenge to public health researchers. A preliminary attempt to meet such challenge comes from a program of assistance to the elderly in the city of Governador Valadares, Minas Gerais, Brazil, with the support of an independent agency backed by the commercial sector (SESC-Minas). A sample of individuals aged 60 and above responded to a semi-structured questionnaire to socioeconomic variables, health conditions and life styles. The survey was a research instrument for the proposal of preventive action and active ageing. The data revealed the main diseases: arterial hypertension (63.8 percent); osteoarthritis (25.5 percent); heart diseases (17%) and diabetes (10.6 percent). “`Polipharmacy” was identified in 29.8% of seniors, including the use of allopathic drugs, phytotherapy and medicinal plants. 25.5 percent reported skin lesions, 72.3% wore dentures and 2.1% orthopedic prostheses. Most elderly people claimed to follow a healthy diet (85.1%), but all reported some form of functional loss. The results suggest that the Program relies on the participation of seniors with health profile similar to the general population of Brazilian elderly, with wide occurrence of chronic diseases, edentulism and high consumption of medicines. This study reinforces the importance of interdisciplinary work as subsidy for the development of more effective interventions, taking into account the perspectives of the elderly and their needs.


Assuntos
Humanos , Masculino , Feminino , Idoso , Dinâmica Populacional , Prevenção de Doenças , Saúde do Idoso , Perfil de Saúde , Saúde Pública
8.
Estud. interdiscip. envelhec ; 21(1): 35-54, abr. 2016. tab
Artigo em Português | Index Psicologia - Periódicos | ID: psi-70359

RESUMO

O envelhecimento da população brasileira trouxe mudanças em seu perfil epidemiológico, como o aumento da ocorrência de doenças crônicas e incapacidades funcionais, além de maior demanda por serviços de saúde, representando um desafio para a Saúde Coletiva no conhecimento das suas especificidades. Nesse sentido, idosos do Programa de Assistência ao Idoso do SESC Minas, na cidade de Governador Valadares (MG), responderam a um questionário semiestruturado para variáveis socioeconômicas, condições de saúde e hábitos de vida a fim de se traçar um diagnóstico desta população e direcionar ações interdisciplinares educativas e preventivas como incentivo ao envelhecimento ativo. Os dados revelaram as principais doenças: hipertensão arterial (63,8%), osteoartrite (25,5%), cardiopatias (17%) e diabetes (10,6%). A polifarmácia foi identificada em 29,8% dos idosos, incluindo o uso de medicamentos alopáticos, fitoterápicos e plantas medicinais. Doze idosos (25,5%) relataram possuir lesões de pele, 72,3% informaram uso de próteses dentárias e 2,1% próteses ortopédicas. A maioria dos idosos classificou sua alimentação como saudável (85,1%), mas todos relataram algum tipo de perda funcional. Os resultados demonstram que o Programa Assistencial conta com idosos com o perfil de saúde semelhante ao da população idosa brasileira, com ampla ocorrência de doenças crônicas, edentulismo, incapacidades funcionais e elevado consumo de medicamentos. O presente estudo reforça a importância do trabalho interdisciplinar como subsídio para o desenvolvimento de intervenções mais sensíveis e eficazes, considerando a perspectiva do próprio indivíduo e suas necessidades. (AU)


The aging of the Brazilian population brought changes in their epidemiological profile: increased occurrence of chronic illnesses and functional disabilities; increased demand for health services. The knowledge of the characteristics and elements of such changes have represented a challenge to public health researchers. A preliminary attempt to meet such challenge comes from a program of assistance to the elderly in the city of Governador Valadares, Minas Gerais, Brazil, with the support of an independent agency backed by the commercial sector (SESC-Minas). A sample of individuals aged 60 and above responded to a semi-structured questionnaire to socioeconomic variables, health conditions and life styles. The survey was a research instrument for the proposal of preventive action and active ageing. The data revealed the main diseases: arterial hypertension (63.8 percent); osteoarthritis (25.5 percent); heart diseases (17%) and diabetes (10.6 percent). “`Polipharmacy” was identified in 29.8% of seniors, including the use of allopathic drugs, phytotherapy and medicinal plants. 25.5 percent reported skin lesions, 72.3% wore dentures and 2.1% orthopedic prostheses. Most elderly people claimed to follow a healthy diet (85.1%), but all reported some form of functional loss. The results suggest that the Program relies on the participation of seniors with health profile similar to the general population of Brazilian elderly, with wide occurrence of chronic diseases, edentulism and high consumption of medicines. This study reinforces the importance of interdisciplinary work as subsidy for the development of more effective interventions, taking into account the perspectives of the elderly and their needs. (AU)


Assuntos
Humanos , Masculino , Feminino , Idoso , Dinâmica Populacional , Perfil de Saúde , Prevenção de Doenças , Saúde do Idoso , Saúde Pública
9.
Clin Sci (Lond) ; 129(7): 533-45, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25967696

RESUMO

Mineralocorticoid receptors (MRs), which are activated by mineralocorticoids and glucocorticoids, actively participate in mechanisms that affect the structure and function of blood vessels. Although experimental and clinical evidence shows that vascular damage in diabetes is associated with structural alterations in large and small arteries, the role of MR in this process needs further studies. Thus, we tested the hypothesis that MR, through redox-sensitive mechanisms, plays a role in diabetes-associated vascular remodelling. Male, 12-14-weeks-old db/db mice, a model of type 2 diabetes and their non-diabetic counterpart controls (db/+) were treated with spironolactone (MR antagonist, 50 mg/kg/day) or vehicle for 6 weeks. Spironolactone treatment did not affect blood pressure, fasting glucose levels or weight gain, but increased serum potassium and total cholesterol in both, diabetic and control mice. In addition, spironolactone significantly reduced serum insulin levels, but not aldosterone levels in diabetic mice. Insulin sensitivity, evaluated by the HOMA (homoeostatic model assessment)-index, was improved in spironolactone-treated diabetic mice. Mesenteric resistance arteries from vehicle-treated db/db mice exhibited inward hypertrophic remodelling, increased number of smooth muscle cells and increased vascular stiffness. These structural changes, determined by morphometric analysis and with a myography for pressurized arteries, were prevented by spironolactone treatment. Arteries from vehicle-treated db/db mice also exhibited augmented collagen content, determined by Picrosirius Red staining and Western blotting, increased reactive oxygen species (ROS) generation, determined by dihydroethidium (DHE) fluorescence, as well as increased expression of NAD(P)H oxidases 1 and 4 and increased activity of mitogen-activated protein kinases (MAPKs). Spironolactone treatment prevented all these changes, indicating that MR importantly contributes to diabetes-associated vascular dysfunction by inducing oxidative stress and by increasing the activity of redox-sensitive proteins.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides/química , Receptores de Mineralocorticoides/fisiologia , Aldosterona/sangue , Animais , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Colágeno/química , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 2/sangue , Etídio/análogos & derivados , Etídio/química , Glucocorticoides/metabolismo , Insulina/sangue , Masculino , Camundongos , Mineralocorticoides/metabolismo , Potássio/sangue , Espécies Reativas de Oxigênio/química , Espironolactona/uso terapêutico
10.
PLoS One ; 9(6): e98895, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24921930

RESUMO

BACKGROUND/AIMS: The aim of this study was to evaluate whether supplementation of high doses of cholecalciferol for two months in normotensive rats results in increased systolic arterial pressure and which are the mechanisms involved. Specifically, this study assesses the potential effect on cardiac output as well as the changes in aortic structure and functional properties. METHODS: Male Wistar rats were divided into three groups: 1) Control group (C, n = 20), with no supplementation of vitamin D, 2) VD3 (n = 19), supplemented with 3,000 IU vitamin D/kg of chow; 3) VD10 (n = 21), supplemented with 10,000 IU vitamin D/kg of chow. After two months, echocardiographic analyses, measurements of systolic arterial pressure (SAP), vascular reactivity, reactive oxygen species (ROS) generation, mechanical properties, histological analysis and metalloproteinase-2 and -9 activity were performed. RESULTS: SAP was higher in VD3 and VD10 than in C rats (p = 0.001). Echocardiographic variables were not different among groups. Responses to phenylephrine in endothelium-denuded aortas was higher in VD3 compared to the C group (p = 0.041). Vascular relaxation induced by acetylcholine (p = 0.023) and sodium nitroprusside (p = 0.005) was impaired in both supplemented groups compared to the C group and apocynin treatment reversed impaired vasodilation. Collagen volume fraction (<0.001) and MMP-2 activity (p = 0.025) was higher in VD10 group compared to the VD3 group. Elastin volume fraction was lower in VD10 than in C and yield point was lower in VD3 than in C. CONCLUSION: Our findings support the view that vitamin D supplementation increases arterial pressure in normotensive rats and this is associated with structural and functional vascular changes, modulated by NADPH oxidase, nitric oxide, and extracellular matrix components.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Colecalciferol/farmacologia , Vasodilatação/efeitos dos fármacos , Vitaminas/farmacologia , Acetilcolina/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/fisiologia , Colecalciferol/administração & dosagem , Colágeno/genética , Colágeno/metabolismo , Suplementos Nutricionais , Elastina/genética , Elastina/metabolismo , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Vasodilatadores/farmacologia , Vitaminas/administração & dosagem
11.
Exp Parasitol ; 120(4): 385-90, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18823980

RESUMO

Through a continuous in vivo drug pressure protocol, using mice as experimental model, we induced benznidazole resistance in Trypanosoma cruzi stocks. Full resistance was obtained for four out of five T. cruzi stocks analyzed. However, the number of benznidazole doses (40-180), as well as the time (4-18 months) necessary to induce resistance varied among the different T. cruzi stocks. The resistance phenotype remained stable after T. cruzi stocks has been maintained by 12 passages in mice (six months) and in acellular culture for the same time. However, the maintenance of resistant parasite for 12 months in acellular culture induces a reduction in its level of benznidazole resistance, while no alteration was detected in parasite maintained for the same time in mice. The data showed the stability of the resistance acquired by drug pressure, but suggest the possibility of reversible changes in the resistance levels after maintenance for long time in acellular culture.


Assuntos
Doença de Chagas/parasitologia , Nitroimidazóis/farmacologia , Parasitemia/parasitologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Doença de Chagas/tratamento farmacológico , Doença de Chagas/imunologia , Ciclofosfamida/farmacologia , Cães , Resistência a Medicamentos , Humanos , Terapia de Imunossupressão , Imunossupressores/farmacologia , Camundongos , Nitroimidazóis/uso terapêutico , Parasitemia/tratamento farmacológico , Parasitemia/imunologia , Tripanossomicidas/uso terapêutico
12.
J Bras Pneumol ; 34(6): 412-9, 2008 Jun.
Artigo em Português | MEDLINE | ID: mdl-18622509

RESUMO

Nitric oxide (NO) is an endogenous vasoactive compound that contributes to pulmonary vascular homeostasis and is produced by three nitric oxide synthase (NOS) isoforms-neuronal NOS (nNOS); inducible NOS (iNOS); and endothelial NOS (eNOS)-all three of which are present in the lung. Studies using pharmacological inhibitors or knockout mice have shown that eNOS-derived NO plays an important role in modulating pulmonary vascular tone and attenuating pulmonary hypertension. However, studies focusing on the role of iNOS have shown that this isoform contributes to the pathophysiology of acute lung injury and acute respiratory distress syndrome. This review aimed at outlining the role played by NO in the control of pulmonary circulation, both under physiological and pathophysiological conditions. In addition, we review the evidence that the L-arginine-NO-cyclic guanosine monophosphate pathway is a major pharmacological target in the treatment of pulmonary vascular diseases.


Assuntos
Hipertensão Pulmonar/fisiopatologia , Óxido Nítrico/fisiologia , Circulação Pulmonar/fisiologia , Animais , Arginina/fisiologia , Ensaios Clínicos como Assunto , GMP Cíclico/fisiologia , Humanos , Camundongos , Camundongos Knockout , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
13.
J. bras. pneumol ; 34(6): 412-419, jun. 2008.
Artigo em Inglês, Português | LILACS | ID: lil-485902

RESUMO

O nitric oxide (NO, óxido nítrico) é um mediador endógeno vasoativo que contribui para a homeostase vascular pulmonar. O NO é produzido por três isoformas das nitric oxide synthases (NOS, óxido nítrico sintases)-NOS neuronial (nNOS); NOS induzida (iNOS); e NOS endotelial (eNOS)-estando as três presentes no pulmão. Estudos que utilizaram inibidores farmacológicos ou camundongos knockout têm demonstrado que o NO derivado da eNOS desempenha importantes papéis ao modular o tônus vascular pulmonar e atenuar a hipertensão pulmonar. Por outro lado, estudos focados no papel da iNOS têm mostrado que essa isoforma contribui para a fisiopatologia da lesão pulmonar aguda e da síndrome do desconforto respiratório agudo. Esta revisão objetivou delinear o papel desempenhado pelo NO no controle da circulação pulmonar, tanto em condições fisiológicas como fisiopatológicas. Além disso, revisamos as evidências de que a via L-arginina-NO-guanosina monofosfato cíclico seja um importante alvo farmacológico para a terapia de doenças vasculares pulmonares.


Nitric oxide (NO) is an endogenous vasoactive compound that contributes to pulmonary vascular homeostasis and is produced by three nitric oxide synthase (NOS) isoforms-neuronal NOS (nNOS); inducible NOS (iNOS); and endothelial NOS (eNOS)-all three of which are present in the lung. Studies using pharmacological inhibitors or knockout mice have shown that eNOS-derived NO plays an important role in modulating pulmonary vascular tone and attenuating pulmonary hypertension. However, studies focusing on the role of iNOS have shown that this isoform contributes to the pathophysiology of acute lung injury and acute respiratory distress syndrome. This review aimed at outlining the role played by NO in the control of pulmonary circulation, both under physiological and pathophysiological conditions. In addition, we review the evidence that the L-arginine-NO-cyclic guanosine monophosphate pathway is a major pharmacological target in the treatment of pulmonary vascular diseases.


Assuntos
Animais , Humanos , Camundongos , Hipertensão Pulmonar/fisiopatologia , Óxido Nítrico/fisiologia , Circulação Pulmonar/fisiologia , Arginina/fisiologia , Ensaios Clínicos como Assunto , GMP Cíclico/fisiologia , Camundongos Knockout , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/biossíntese
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