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1.
Molecules ; 29(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257386

RESUMO

Cannabidiol (CBD), a non-psychoactive compound derived from Cannabis Sativa, has garnered increasing attention for its diverse therapeutic potential. This comprehensive review delves into the complex pharmacokinetics of CBD, including factors such as bioavailability, distribution, safety profile, and dosage recommendations, which contribute to the compound's pharmacological profile. CBD's role as a pharmacological inhibitor is explored, encompassing interactions with the endocannabinoid system and ion channels. The compound's anti-inflammatory effects, influencing the Interferon-beta and NF-κB, position it as a versatile candidate for immune system regulation and interventions in inflammatory processes. The historical context of Cannabis Sativa's use for recreational and medicinal purposes adds depth to the discussion, emphasizing CBD's emergence as a pivotal phytocannabinoid. As research continues, CBD's integration into clinical practice holds promise for revolutionizing treatment approaches and enhancing patient outcomes. The evolution in CBD research encourages ongoing exploration, offering the prospect of unlocking new therapeutic utility.


Assuntos
Canabidiol , Cannabis , Alucinógenos , Humanos , Canabidiol/farmacologia , Canabidiol/uso terapêutico , Disponibilidade Biológica , Agonistas de Receptores de Canabinoides , Carbidopa
2.
Circulation ; 148(15): 1165-1178, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37681311

RESUMO

BACKGROUND: Clonal hematopoiesis (CH), which results from an array of nonmalignant driver gene mutations, can lead to altered immune cell function and chronic disease, and has been associated with worse outcomes in patients with heart failure (HF) with reduced ejection fraction. However, the role of CH in the prognosis of HF with preserved ejection fraction (HFpEF) has been understudied. This study aimed to characterize CH in patients with HFpEF and elucidate its causal role in a murine model. METHODS: Using a panel of 20 candidate CH driver genes and a variant allele fraction cutoff of 0.5%, ultradeep error-corrected sequencing identified CH in a cohort of 81 patients with HFpEF (mean age, 71±6 years; ejection fraction, 63±5%) and 36 controls without a diagnosis of HFpEF (mean age, 74±7 years; ejection fraction, 61.5±8%). CH was also evaluated in a replication cohort of 59 individuals with HFpEF. RESULTS: Compared with controls, there was an enrichment of TET2-mediated CH in the HFpEF patient cohort (12% versus 0%, respectively; P=0.02). In the HFpEF cohort, patients with CH exhibited exacerbated diastolic dysfunction in terms of E/e' (14.9 versus 11.7, respectively; P=0.0096) and E/A (1.69 versus 0.89, respectively; P=0.0206) compared with those without CH. The association of CH with exacerbated diastolic dysfunction was corroborated in a validation cohort of individuals with HFpEF. In accordance, patients with HFpEF, an age ≥70 years, and CH exhibited worse prognosis in terms of 5-year cardiovascular-related hospitalization rate (hazard ratio, 5.06; P=0.042) compared with patients with HFpEF and an age ≥70 years without CH. To investigate the causal role of CH in HFpEF, nonconditioned mice underwent adoptive transfer with Tet2-wild-type or Tet2-deficient bone marrow and were subsequently subjected to a high-fat diet/L-NAME (Nω-nitro-l-arginine methyl ester) combination treatment to induce features of HFpEF. This model of Tet2-CH exacerbated cardiac hypertrophy by heart weight/tibia length and cardiomyocyte size, diastolic dysfunction by E/e' and left ventricular end-diastolic pressure, and cardiac fibrosis compared with the Tet2-wild-type condition. CONCLUSIONS: CH is associated with worse heart function and prognosis in patients with HFpEF, and a murine experimental model of Tet2-mediated CH displays greater features of HFpEF.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Camundongos , Animais , Idoso , Idoso de 80 Anos ou mais , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/tratamento farmacológico , Volume Sistólico , Função Ventricular Esquerda , Hematopoiese Clonal/genética , Disfunção Ventricular Esquerda/genética
3.
Curr Atheroscler Rep ; 25(3): 105-111, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36808603

RESUMO

PURPOSE OF REVIEW: Clonal hematopoiesis (CH) is a prevalent condition that results from the acquisition of somatic mutations in hematopoietic stem cells. When these mutations occur in "driver" genes, they can potentially confer fitness advantages to the cell, leading to a clonal expansion. While most clonal expansions of mutant cells are generally considered to be asymptomatic since they do not impact overall blood cell numbers, CH carriers display long-term risks of all-cause mortality and age-associated diseases including cardiovascular disease (CVD). This review summarizes recent findings in CH related to aging, atherosclerotic CVD, and inflammation, emphasizing epidemiological and mechanistic studies, and potential therapeutic options to treat CVDs that are promoted by CH. RECENT FINDINGS: Epidemiological studies have revealed associations between CH and CVDs. Experimental studies with CH models employing the Tet2- and Jak2-mutant mouse lines display inflammasome activation and a chronic inflammatory state that leads to accelerated atherosclerotic lesion growth. A body of evidence suggests that CH represents a new causal risk factor for CVD. Studies also indicate that understanding an individual's CH status could provide guidance for personalized approaches to treat atherosclerosis and other CVDs with anti-inflammatory drugs.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Humanos , Animais , Camundongos , Hematopoiese Clonal , Hematopoese/genética , Aterosclerose/genética , Inflamação/complicações , Envelhecimento/genética , Envelhecimento/patologia , Doenças Cardiovasculares/etiologia , Mutação
5.
JCI Insight ; 6(13)2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236050

RESUMO

Therapy-related clonal hematopoiesis (t-CH) is often observed in cancer survivors. This form of clonal hematopoiesis typically involves somatic mutations in driver genes that encode components of the DNA damage response and confer hematopoietic stem and progenitor cells (HSPCs) with resistance to the genotoxic stress of the cancer therapy. Here, we established a model of TP53-mediated t-CH through the transfer of Trp53 mutant HSPCs to mice, followed by treatment with a course of the chemotherapeutic agent doxorubicin. These studies revealed that neutrophil infiltration in the heart significantly contributes to doxorubicin-induced cardiac toxicity and that this condition is amplified in the model of Trp53-mediated t-CH. These data suggest that t-CH could contribute to the elevated heart failure risk that occurs in cancer survivors who have been treated with genotoxic agents.


Assuntos
Cardiotoxicidade , Hematopoiese Clonal/genética , Dano ao DNA/efeitos dos fármacos , Doxorrubicina , Infiltração de Neutrófilos/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Cardiotoxicidade/etiologia , Cardiotoxicidade/metabolismo , Cardiotoxicidade/patologia , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Doxorrubicina/toxicidade , Técnicas de Transferência de Genes , Camundongos
7.
Hypertens Res ; 44(7): 791-802, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33612826

RESUMO

ß-Adrenergic blockers are no longer recommended as first-line therapy due to the reduced cardioprotection of traditional ß-blockers compared with other antihypertensive drugs. It is unknown whether third-generation ß-blockers share the limitations of traditional ß-blockers. The aim of the present study was to compare the effects of nebivolol or atenolol on central and peripheral systolic blood pressure (SBP) and its variability and target organ damage (TOD) in N-nitro-L-arginine methyl ester (L-NAME) hypertensive rats. Male Wistar rats were treated with L-NAME for 8 weeks together with oral administration of nebivolol 30 mg/kg (n = 8), atenolol 90 mg/kg (n = 8), or vehicle (n = 8). The control group was composed of vehicle-treated Wistar rats. SBP and its variability, as well as echocardiographic parameters, were assessed during the last 2 weeks of treatment. Tissue levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and transforming growth factor ß (TGF-ß), and histopathological parameters were evaluated in the left ventricle and aorta. Nebivolol had a greater ability than atenolol to decrease central SBP and mid-term and short-term blood pressure variability (BPV) in L-NAME rats. Echocardiographic analysis showed that nebivolol was more effective than atenolol on E/A wave ratio normalization. Compared with atenolol treatment, nebivolol had a greater protective effect on different TOD markers, inducing a decrease in collagen deposition and a reduction in the proinflammatory cytokines IL-6 and TNF-α in the left ventricle and aorta. Our findings suggest that the adverse hemodynamic profile and the reduced cardiovascular protection reported with traditional ß-blockers must not be carried forward to third-generation ß-blockers.


Assuntos
Atenolol , Hipertensão , Nebivolol , Animais , Anti-Hipertensivos/farmacologia , Atenolol/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Hipertensão/tratamento farmacológico , Masculino , Nebivolol/farmacologia , Ratos , Ratos Wistar , Resultado do Tratamento
8.
J Hypertens ; 38(3): 536-545, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028517

RESUMO

BACKGROUND: ß-blockers are no longer considered as first-line antihypertensive drugs due to their lower cardioprotection. METHOD: Considering the differences in the pharmacological properties of ß-blockers, the present work compared the effects of third-generation ß-blockers - carvedilol and nebivolol - with a first-line agent - amlodipine - on hemodynamic parameters, including short-term blood pressure variability (BPV), and their ability to prevent target organ damage in spontaneously hypertensive rats (SHR). SHR rats were orally treated with carvedilol, nebivolol, atenolol, amlodipine or vehicle for 8 weeks. Wistar Kyoto rats treated with vehicle were used as normotensive group. Echocardiographic evaluation, BP, and short-term BPV measurements were performed. Left ventricle and thoracic aorta were removed for histological evaluations and to assess the expression of transforming growth factor ß (TGF-ß), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). RESULTS: Carvedilol, nebivolol or amlodipine induced a greater reduction of carotid BP, short-term BPV and echocardiography parameters than atenolol in SHR rats. Carvedilol, nebivolol and amlodipine were more effective than atenolol in the prevention of cardiac hypertrophy, and cardiac and aortic collagen deposit. Carvedilol and nebivolol, but not atenolol, reduced the expressions of fibrotic and inflammatory biomarkers - TGF-ß, TNF-α and IL-6 - in SHR rats to a similar extent to that of amlodipine. CONCLUSION: Chronic treatment with carvedilol or nebivolol attenuates carotid BP and short-term BPV, and reduces target organ damage in SHR to a greater extent than atenolol. Our findings suggest that the lower cardiovascular protection of nonvasodilating ß-blockers, as atenolol, in hypertension must not be translated to third-generation ß-blockers.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Anlodipino/farmacologia , Anti-Hipertensivos/farmacologia , Atenolol/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Antagonistas Adrenérgicos beta/efeitos adversos , Anlodipino/efeitos adversos , Animais , Aorta/efeitos dos fármacos , Atenolol/efeitos adversos , Citocinas/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Ratos , Ratos Endogâmicos SHR
9.
Expert Opin Drug Metab Toxicol ; 15(1): 1-13, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30582386

RESUMO

INTRODUCTION: Although main antihypertensive drugs are able to efficiently reduce blood pressure, only a third of treated hypertensive patients achieve optimal blood pressure control. Extensive interpatient variability on drug metabolism and oral disposition of blood pressure lowering drugs can contribute to this failure in hypertension management. Areas covered: The aim of the present review is to update the knowledge on the features of hepatic metabolism of the main antihypertensive agents, including ß-blockers, calcium channel blockers, angiotensin receptor blockers, and angiotensin converting enzyme inhibitors. The factors that contribute to the large interindividual variability of main antihypertensive drugs are also covered. Expert opinion: The variability of plasma concentration of antihypertensive drugs due to the involvement of hepatic metabolism can contribute to the inadequate control of blood pressure in the daily clinical practice. Genotype screening of specific hepatic drug-metabolizing enzymes may contribute to optimize dose selection and to increase the rate of blood pressure control in patients treated with specific ß-blockers, calcium channel blockers, and angiotensin receptor blockers.


Assuntos
Anti-Hipertensivos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/farmacocinética , Antagonistas de Receptores de Angiotensina/administração & dosagem , Antagonistas de Receptores de Angiotensina/farmacocinética , Anti-Hipertensivos/farmacocinética , Anti-Hipertensivos/farmacologia , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/farmacocinética , Relação Dose-Resposta a Droga , Genótipo , Humanos
10.
Curr Pharm Des ; 23(31): 4658-4677, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28911302

RESUMO

OBJECTIVE: This review covers the pharmacokinetics and pharmacodynamic of ß-blockers, the rationale for their use, some recent controversies in its use for managing hypertension, as well as, the beneficial properties of the third-generation ß-blockers beyond hypertension. BACKGROUND: The efficacy and safety of ß-blockers in the treatment of hypertension and other cardiovascular diseases have been established during more than 50 years of clinical experience. Recent updates of clinical guidelines have downgraded the use of ß-blockers for the treatment of uncomplicated hypertension to second and third line therapy. It is a well-known fact that ß-blockers exhibit heterogeneous pharmacokinetic and pharmacodynamic properties that clearly influence their clinical efficacy and tolerability in the management of essential hypertension. Conventional nonvasodilating ß-blockers (atenolol and metoprolol) are inferior to first-line antihypertensive agents in terms of cardioprotection due to lower ability to reduce central blood pressure and its variability and the adverse effects on glycemic and lipid metabolism. CONCLUSION: New vasodilating ß-blockers, mainly carvedilol and nebivolol, show enhanced hemodynamic and metabolic properties, which probably result in a higher prevention of major cardiovascular events in hypertensive patients. Despite head-to-head clinical trials comparing the effects of vasodilating vs nonvasodilating ß-blockers on hard clinical endpoints are lacking, the current evidence suggests that third-generation ß-blockers are superior to conventional ß-blockers for the prevention of cardiovascular events in patients with essential hypertension. Moreover, beyond their antihypertensive properties, third-generation ß-blockers also have pleiotropic, antioxidant and antiinflammatory effects that warrant a "promissory new era" of this newly group.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão Essencial/tratamento farmacológico , Antagonistas Adrenérgicos beta/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Índice Glicêmico/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos
11.
J Nutr Biochem ; 46: 109-116, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28499147

RESUMO

Metabolic syndrome is an array of closely metabolic disorders that includes glucose intolerance/insulin resistance, central obesity, dyslipidemia, and hypertension. Fructose, a highly lipogenic sugar, has profound metabolic effects in adipose tissue, and has been associated with the etiopathology of many components of the metabolic syndrome. In adipocytes, the enzyme 11 ß-HSD1 amplifies local glucocorticoid production, being a key player in the pathogenesis of central obesity and metabolic syndrome. 11 ß-HSD1 reductase activity is dependent on NADPH, a cofactor generated by H6PD inside the endoplasmic reticulum. Our focus was to explore the effect of fructose overload on epididymal white adipose tissue (EWAT) machinery involved in glucocorticoid production and NADPH and oxidants metabolism. Male Sprague-Dawley rats fed with a fructose solution (10% (w/v) in tap water) during 9 weeks developed some characteristic features of metabolic syndrome, such as hypertriglyceridemia, and hypertension. In addition, high levels of plasma and EWAT corticosterone were detected. Activities and expressions of H6PD and 11 ß-HSD1, NAPDH content, superoxide anion production, expression of NADPH oxidase 2 subunits, and indicators of oxidative metabolism were measured. Fructose overloaded rats showed an increased potential in oxidant production respect to control rats. In parallel, in EWAT from fructose overloaded rats we found higher expression/activity of H6PD and 11 ß-HSD1, and NADPH/NADP+ ratio. Our in vivo results support that fructose overload installs in EWAT conditions favoring glucocorticoid production through higher H6PD expression/activity supplying NADPH for enhanced 11 ß-HSD1 expression/activity, becoming this tissue a potential extra-adrenal source of corticosterone under these experimental conditions.


Assuntos
Tecido Adiposo Branco/metabolismo , Corticosterona/metabolismo , Frutose/efeitos adversos , NADP/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Pressão Sanguínea , Peso Corporal , Corticosterona/sangue , Ingestão de Alimentos , Epididimo/efeitos dos fármacos , Epididimo/metabolismo , Frutose/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Masculino , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , NADPH Oxidase 2/metabolismo , Ratos Sprague-Dawley
12.
Sci Signal ; 4(200): pt7, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22114142

RESUMO

The vertebrate Hedgehog (Hh) pathway has essential functions during development and tissue homeostasis in normal physiology, and its dysregulation is a common theme in cancer. The Hh ligands (Sonic Hh, Indian Hh, and Desert Hh) bind to the receptors Patched1 and Patched2, resulting in inhibition of their repressive effect on Smoothened (Smo). Smo is a seven-transmembrane protein, which was only recently shown to function as a G protein-coupled receptor (GPCR) with specificity toward the heterotrimeric guanine nucleotide-binding protein G(i). In addition to activating G(i), Smo signals through its C-terminal tail to inhibit Suppressor of Fused, resulting in stabilization and activation of the Gli family of transcription factors, which execute a transcriptional response to so-called "canonical Hh signaling." In this Presentation, we illustrate two outcomes of Hh signaling that are independent of Gli transcriptional activity and, thus, are defined as "noncanonical." One outcome is dependent on Smo coupling to G(i) proteins and exerts changes to the actin cytoskeleton through stimulation of the small guanosine triphosphatases (GTPases) RhoA and Rac1. These cytoskeletal changes promote migration in fibroblasts and tubulogenesis in endothelial cells. Signaling through the other noncanonical Hh pathway is independent of Smo and inhibits Patched1-induced cell death.


Assuntos
Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Proteínas Hedgehog/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Fatores de Transcrição/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Morte Celular/fisiologia , Movimento Celular/fisiologia , Citoesqueleto/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Ativação Enzimática/fisiologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Receptores Patched , Receptor Patched-1 , Receptor Patched-2 , Estrutura Terciária de Proteína , Receptores de Superfície Celular/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/fisiologia , Receptor Smoothened , Proteína GLI1 em Dedos de Zinco
13.
Redox Rep ; 16(2): 49-55, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21722412

RESUMO

We have previously demonstrated that the induction of heme oxygenase-1 (HO-1) (EC 1.14.99.3) plays a protective role against oxidative stress in leaves and nodules of soybean plants subjected to cadmium, UV-B radiation, and salt stress. Here, we investigated HO-1, localization and their relationship with oxidative stress in different growth stages of soybean plants roots inoculated with Bradyrhizobium japonicum (3, 5, 7, 10, and 20 days post-inoculation) and nodules. After 7 days of inoculation, we observed a 70% increase in thiobarbituric acid-reactive substances that correlates with an enhancement in the gene expression of HO-1, catalase, and superoxide dismutase. Furthermore, the inhibition of HO-1 activity by Zn-protoporphyrin IX produced an increase in lipid peroxidation and a decrease in glutathione content suggesting that, in this symbiotic process, HO-1 may act as a signal molecule that protects the root against oxidative stress. We determined, for the first time, the tissular localization of HO-1 in nodules by electron-microscope examination. These results undoubtedly demonstrated that this enzyme is localized only in the plant tissue and its overexpression may play an important role as antioxidant defense in the plant. Moreover, we demonstrate that, in roots, HO-1 is induced by oxidative stress produced by inoculation of B. japonicum and exerts an antioxidant response against it.


Assuntos
Bradyrhizobium/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Glycine max/enzimologia , Heme Oxigenase-1/metabolismo , Estresse Oxidativo , Simbiose , Bradyrhizobium/efeitos dos fármacos , Catalase/genética , Catalase/metabolismo , Glutationa/metabolismo , Heme Oxigenase-1/genética , Técnicas Imunoenzimáticas , Peroxidação de Lipídeos/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Protoporfirinas/farmacologia , RNA Mensageiro/genética , RNA de Plantas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sais/farmacologia , Glycine max/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
14.
Pharmacology ; 87(5-6): 341-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21646819

RESUMO

Heme oxygenase (HO) is an enzyme that is involved in numerous secondary actions. One of its products, CO, seems to have an important but unclear role in blood pressure regulation. CO exhibits a vasodilator action through the activation of soluble guanylate cyclase and the subsequent production of cyclic guanosine monophosphate (cGMP). The aim of the present study was to determine whether pathological and pharmacological HO-1 overexpression has any regulatory role on blood pressure in a renovascular model of hypertension. We examined the effect of zinc protoporyphyrin IX (ZnPP-IX) administration, an inhibitor of HO activity, on mean arterial pressure (MAP) and heart rate in sham-operated and aorta-coarcted (AC) rats and its interaction with the nitric oxide synthase (NOS) pathway. Inhibition of HO increased MAP in normotensive rats with and without hemin pretreatment but not in hypertensive rats. Pretreatment with NG-nitro-L-arginine methyl ester blocked the pressor response to ZnPP-IX, suggesting a key role of NOS in the cardiovascular action of HO inhibition. In the same way, AC rats, an experimental model of hypertension with impaired function and low expression of endothelial NOS (eNOS), did not show any cardiovascular response to inhibition or induction of HO. This finding suggests that eNOS was necessary for modulating the CO response in the hypertensive group. In conclusion, the present study suggests that HO regulates blood pressure through CO only when the NOS pathway is fully operative. In addition, chronic HO induction fails to attenuate the hypertensive stage induced by coarctation as a consequence of the impairment of the NOS pathway.


Assuntos
Heme Oxigenase-1/biossíntese , Hipertensão/enzimologia , Óxido Nítrico Sintase/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Monóxido de Carbono/farmacologia , GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hemina/metabolismo , Hipertensão/genética , Hipertensão/metabolismo , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Protoporfirinas/farmacologia , Ratos , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/metabolismo , Guanilil Ciclase Solúvel
15.
J Biol Chem ; 286(22): 19589-96, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21474452

RESUMO

Evidence supporting the functionality of Smoothened (SMO), an essential transducer in most pathways engaged by Hedgehog (Hh), as a G(i)-coupled receptor contrasts with the lack of an apparently consistent requirement for G(i) in Hh signal transduction. In the present study, we sought to evaluate the role of SMO-G(i) coupling in fibroblast migration induced by Sonic Hedgehog (Shh). Our results demonstrate an absolute requirement for G(i) in Shh-induced fibroblast migration. We found that Shh acutely stimulates the small Rho GTPases Rac1 and RhoA via SMO through a G(i) protein- and PI3K-dependent mechanism, and that these are required for cell migration. These responses were independent of transcription by Gli and of the C-terminal domain of SMO, as we show using a combination of molecular and genetic tools. Our findings provide a mechanistic model for fibroblast migration in response to Shh and underscore the role of SMO-G(i) coupling in non-canonical Hh signaling.


Assuntos
Movimento Celular/fisiologia , Fibroblastos/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Proteínas Hedgehog/metabolismo , Neuropeptídeos/metabolismo , Transdução de Sinais/fisiologia , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Animais , Fibroblastos/citologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Proteínas Hedgehog/genética , Camundongos , Camundongos Knockout , Células NIH 3T3 , Neuropeptídeos/genética , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptor Smoothened , Proteínas rac de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP , Proteínas rho de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP
16.
Phytochemistry ; 71(14-15): 1700-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20708206

RESUMO

Heme oxygenase (HO) has antioxidant properties and is up-regulated by reactive oxygen species (ROS) in ultraviolet-B-irradiated soybean plants. This study shows that nitric oxide (NO) protects against oxidative damage and that nitric oxide synthase (NOS)-like activity is also required for HO-1 induction under UV-B radiation. Pre-treatments with sodium nitroprussiate (SNP), a NO-donor, prevented chlorophyll loss, H(2)O(2) and O(2)(*-) accumulation, and ion leakage in UV-B-treated plants. HO activity was significantly enhanced by NO and showed a positive correlation with HO-1 transcript levels. In fact, HO-1 mRNA levels were increased 2.1-fold in 0.8 mM SNP-treated plants, whereas subsequent UV-B irradiation augmented this expression up to 3.5-fold with respect to controls. This response was not observed using ferrocyanide, a SNP inactive analog, and was effectively blocked by 2-(4-carboxyphenil)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), a specific NO-scavenger. In addition, experiments carried out in the presence of N(G)-nitro-L-arginine methyl ester (L-NAME) or tungsten, well-known inhibitors of NOS and nitrate reductase, showed that NOS is the endogenous source of NO that mediates HO-1 expression. In summary, we found that NO is involved in the signaling pathway leading to HO-1 up-regulation under UV-B, and that a balance between NO and ROS is important to trigger the antioxidant response against oxidative stress.


Assuntos
Glycine max/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/biossíntese , Raios Ultravioleta , Clorofila/análise , Clorofila/metabolismo , Clorofila/efeitos da radiação , Heme Oxigenase (Desciclizante)/efeitos da radiação , Peróxido de Hidrogênio/análise , NG-Nitroarginina Metil Éster/química , Óxido Nítrico Sintase/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Folhas de Planta/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Glycine max/genética , Glycine max/efeitos da radiação , Substâncias Reativas com Ácido Tiobarbitúrico/análise
17.
J Cardiovasc Pharmacol ; 54(4): 348-54, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19687745

RESUMO

Oxidative stress produced through reactive oxygen species (ROS) enhancement is considered to play a key role in the development and maintenance of hypertension. In the vasculature, the most important source of ROS is the reduced nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase enzyme. The principal stimulus of this enzyme is angiotensin II (Ang II). However, oxidative stress seems to be present in virtually all forms of hypertension including low-renin hypertension, where the levels of Ang II are reduced. For this reason, the question is if ROS generation is induced by Ang II or it is a consequence of hypertension. We used as hypertensive model the aortic coarctated rats, which were treated with losartan or minoxidil for 7 days. Thoracic aortic segments were excised, and the NAD(P)H oxidase subunits expression, oxidative stress parameters, and heme oxygenase-1 abundance were evaluated. Hypertensive animals had an increase in the activity and expression of NAD(P)H oxidase and, as a consequence, in the oxidative stress parameters. Interestingly, either losartan or minoxidil administration blunted those parameters, indicating that arterial pressure is the key factor in the development of oxidative stress in the hypertensive aorta. We suggest that antihypertensive drug administration at the beginning of this pathology delays the oxidative stress generation, thus preventing the aggravation of this disease.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão Renal/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Animais , Anti-Hipertensivos/administração & dosagem , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/enzimologia , Aorta Torácica/metabolismo , Modelos Animais de Doenças , Heme Oxigenase (Desciclizante)/metabolismo , Hipertensão Renal/metabolismo , Hipertensão Renal/fisiopatologia , Losartan/administração & dosagem , Losartan/uso terapêutico , Masculino , Minoxidil/administração & dosagem , Minoxidil/uso terapêutico , NADPH Oxidases/biossíntese , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
18.
Regul Pept ; 156(1-3): 28-33, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19445972

RESUMO

This study was performed to provide insight into the regulatory role of angiotensin II and arterial pressure on the activity of antioxidant enzymes and oxidative stress generation in the hypertensive kidney from an experimental animal model of renovascular hypertension. Aortic coarcted and sham-operated rats received vehicle, losartan or minoxidil in their drinking water. After 7 d of treatment rats were sacrificed; hypertensive kidneys were excised, and the NAD(P)H oxidase subunits expression, TBARS production, glutathione level and the activity of heme oxygenase-1 and classical antioxidant enzymes, were evaluated. Losartan administration significantly reduced oxidative stress generation decreasing NAD(P)H oxidase expression, independently of the drop in arterial pressure. On the other hand, antioxidant enzymes were regulated by arterial pressure and they were not implicated in kidney protection against oxidative damage. Findings here reported strongly suggest that clinical therapeutics with the Ang II type 1 receptor blocker prevents oxidative stress generation and may attenuate the kidney oxidative damage in the renovascular hypertension. We hypothesize that the pathway followed by the Ang II blocker to achieve this renoprotection, though independent of the primary antioxidant enzymatic system, depends on NAD(P)H oxidase downregulation.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Losartan/farmacologia , NADPH Oxidases/metabolismo , Animais , Western Blotting , Glutationa/metabolismo , Heme Oxigenase-1/metabolismo , Peróxido de Hidrogênio/metabolismo , Hipertensão Renovascular/tratamento farmacológico , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
19.
Hypertens Res ; 31(2): 325-34, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18360053

RESUMO

The aim of this study was to provide new insights into the role of angiotensin II and arterial pressure in the regulation of antioxidant enzyme activities in a renovascular model of cardiac hypertrophy. For this purpose, aortic coarcted rats were treated with losartan or minoxidil for 7 days. Angiotensin II induced cardiac hypertrophy and oxidative stress via Nox4, p22(phox) and p47(phox), which are components of the NAD(P)H oxidase. Antioxidant enzymes were regulated by arterial pressure and were not implicated in cardiac hypertrophy. Heme oxygenase-1, the rate-limiting enzyme in heme catabolism, behaved as a catalase and glutathione peroxidase, and is regulated by arterial pressure. In summary, the present report indicates that cardiac hypertrophy, induced by renovascular hypertension, depends on angiotensin II through reactive oxygen species and is not prevented by the action of antioxidant enzymes.


Assuntos
Angiotensina II/fisiologia , Cardiomegalia/etiologia , Hipertensão Renovascular/complicações , Estresse Oxidativo , Animais , Pressão Sanguínea , Catalase/metabolismo , Glutationa/análise , Hipertensão Renovascular/metabolismo , Losartan/farmacologia , Masculino , NADPH Oxidases/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
20.
Antioxid Redox Signal ; 9(3): 393-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17184180

RESUMO

Lisinopril is an inhibitor of the renin-angiotensin system. Does lisinopril minimize oxidative damage in spontaneously hypertensive rats (SHR) in comparison with the normotensive genetic controls Wistar Kyoto (WKY)? The authors note that lisinopril contained lipid peroxidation, elevated tissue glutathione levels, and influenced the activity of antioxidant enzymes such as catalase and glutathione peroxidase. Studies in humans testing the hypothesis that lisinopril has antioxidant function in vivo are warranted.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Antioxidantes/farmacologia , Lisinopril/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
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