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1.
Intern Emerg Med ; 15(1): 67-71, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30868444

RESUMO

Some evidence suggests a relationship between thyroid dysfunction and uric acid (UA) metabolism, but the potential influential role of thyroid hormones on UA metabolism is still debated. This report was designed to evaluate the influential role of levothyroxine (L-T4) replacement therapy on circulating levels of UA in patients with recent onset post-thyroidectomy subclinical hypothyroidism. Circulating levels of thyroid hormones, UA and other metabolic parameters were assessed in 155 recently thyroidectomized patients (131 females, mean age 51.1 ± 12.7 years) at baseline (5-7 day after surgery) and after 2 months under replacement therapy with L-T4. At baseline, circulating levels of thyroid hormones were indicative of a subclinical hypothyroidism (TSH 8.2 ± 5.1 mU/mL, FT3 2.1 ± 0.7 pg/mL, FT4 9.2 ± 3.4 pg/mL). The mean serum UA concentration was 5.0 ± 1.3 mg/dL, while the prevalence of hyperuricemia, defined by serum UA levels > 6 mg/dL, was 22.6%. Serum UA levels at baseline were significantly correlated with HOMA-IR index (r = 0.475, p < 0.0001). After 2 months under the replacement therapy with L-T4, both serum UA levels (- 1.2 ± 0.9 mg/dL, p < 0.0001 vs. baseline) and HOMA-IR (- 0.3 ± 1.5 mmol/L, p = 0.0328 vs. baseline) significantly decreased. Multivariate regression analysis revealed that changes in HOMA-IR explained 23% of the variations of serum UA levels under L-T4 replacement therapy (ß = 0.295, p < 0.0001, R2 = 0.230). Our study suggests that thyroid hormones could modulate UA metabolism in patients with recent onset subclinical hypothyroidism likely by improving insulin sensitivity.


Assuntos
Hormônios Tireóideos/farmacologia , Ácido Úrico/metabolismo , Adulto , Idoso , Feminino , Terapia de Reposição Hormonal/métodos , Humanos , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/metabolismo , Masculino , Pessoa de Meia-Idade , Hormônios Tireóideos/análise , Tireoidectomia/estatística & dados numéricos , Ácido Úrico/análise
2.
Hypertension ; 69(5): 942-949, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28289180

RESUMO

Patients with central obesity have impaired insulin-stimulated vasodilation and increased ET-1 (endothelin 1) vasoconstriction, which may contribute to insulin resistance and vascular damage. Apelin enhances insulin sensitivity and glucose disposal but also acts as a nitric oxide (NO)-dependent vasodilator and a counter-regulator of AT1 (angiotensin [Ang] II type 1) receptor-induced vasoconstriction. We, therefore, examined the effects of exogenous (Pyr1)apelin on NO-mediated vasodilation and Ang II- or ET-1-dependent vasoconstrictor tone in obese patients. In the absence of hyperinsulinemia, forearm blood flow responses to graded doses of acetylcholine and sodium nitroprusside were not different during saline or apelin administration (both P>0.05). During intra-arterial infusion of regular insulin, however, apelin enhanced the vasodilation induced by both acetylcholine and nitroprusside (both P<0.05). Interestingly, the vasodilator effect of concurrent blockade of AT1 (telmisartan) and AT2 (PD 123,319) receptors was blunted by apelin (3±5% versus 32±9%; P<0.05). Similarly, during apelin administration, blockade of ETA receptors (BQ-123) resulted in lower vasodilator response than during saline (23±10% versus 65±12%; P<0.05). NO synthase inhibition by L-NMMA (l-N-monometylarginine) during the concurrent blockade of either Ang II or ETA receptors resulted in similar vasoconstriction in the absence or presence of apelin (P>0.05). In conclusion, in patients with central obesity, apelin has favorable effects not only to improve insulin-stimulated endothelium-dependent and endothelium-independent vasodilator responses but also to blunt Ang II- and ET-1-dependent vasoconstriction by a mechanism not involving NO. Taken together, our results suggest that targeting the apelin system might favorably impact some hemodynamic abnormalities of insulin-resistant states like obesity.


Assuntos
Anexinas/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Obesidade/fisiopatologia , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Adulto , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 2 de Angiotensina II/farmacologia , Apelina , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Feminino , Antebraço/irrigação sanguínea , Humanos , Imidazóis/farmacologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Nitroprussiato/farmacologia , Piridinas/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Telmisartan , ômega-N-Metilarginina/farmacologia
3.
Diabetes ; 66(5): 1214-1221, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28174289

RESUMO

Obese patients have impaired vasodilator reactivity and increased endothelin 1 (ET-1)-mediated vasoconstriction, two abnormalities contributing to vascular dysfunction. Obestatin, a product of the ghrelin gene, in addition to favorable effects on glucose and lipid metabolism, has shown nitric oxide (NO)-dependent vasodilator properties in experimental models. Given these premises, we compared the effects of exogenous obestatin on forearm flow in lean and obese subjects and assessed its influence on ET-1-dependent vasoconstrictor tone in obesity. In both lean and obese participants, infusion of escalating doses of obestatin resulted in a progressive increase in blood flow from baseline (both P < 0.001). This vasodilation was predominantly mediated by enhanced NO activity, because NG-monomethyl-l-arginine markedly blunted the flow response to obestatin in both groups (both P < 0.05 vs. saline). In obese subjects, antagonism of ETA receptors by BQ-123 increased forearm flow during saline (P < 0.001) but did not induce additional vasodilation (P > 0.05) during obestatin. Circulating obestatin levels were not different between lean and obese participants (P = 0.41). Our findings indicate that obestatin causes NO-dependent vasodilation in the human circulation. This effect is preserved in obesity, where it is accompanied by reduced ET-1-mediated vasoconstriction. These latter observations make obestatin a promising target for vascular prevention in obesity and diabetes.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Grelina/farmacologia , Obesidade Abdominal , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adulto , Estudos de Casos e Controles , Antagonistas do Receptor de Endotelina A/farmacologia , Endotelina-1 , Inibidores Enzimáticos/farmacologia , Feminino , Antebraço/irrigação sanguínea , Humanos , Masculino , Óxido Nítrico/metabolismo , Peptídeos Cíclicos/farmacologia , ômega-N-Metilarginina/farmacologia
4.
Diabetes Care ; 36(3): 683-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23069838

RESUMO

OBJECTIVE: Patients with the metabolic syndrome (MetS) have impaired insulin-induced enhancement of vasodilator responses. The incretin hormone glucagon-like peptide 1 (GLP-1), beyond its effects on blood glucose, has beneficial actions on vascular function. This study, therefore, aimed to assess whether GLP-1 affects insulin-stimulated vasodilator reactivity in patients with the MetS. RESEARCH DESIGN AND METHODS: Forearm blood flow responses to acetylcholine (ACh) and sodium nitroprusside (SNP) were assessed in MetS patients before and after the addition of GLP-1 to an intra-arterial infusion of saline (n = 5) or insulin (n = 5). The possible involvement of oxidative stress in the vascular effects of GLP-1 in this setting was investigated by infusion of vitamin C (n = 5). The receptor specificity of GLP-1 effect during hyperinsulinemia was assessed by infusing its metabolite GLP-1(9-36) (n = 5). The metabolic actions of GLP-1 were also tested by analyzing forearm glucose disposal during hyperinsulinemia (n = 5). RESULTS: In MetS patients, GLP-1 enhanced endothelium-dependent and -independent responses to ACh and SNP, respectively, during hyperinsulinemia (P < 0.001 for both), but not during saline (P > 0.05 for both). No changes in vasodilator reactivity to ACh and SNP were seen after GLP-1 was added to insulin and vitamin C (P > 0.05 for both) and after GLP-1(9-36) was given during hyperinsulinemia (P > 0.05 for both). Also, GLP-1 did not affect forearm glucose extraction and uptake during hyperinsulinemia (P > 0.05 for both). CONCLUSIONS: In patients with the MetS, GLP-1 improves insulin-mediated enhancement of endothelium-dependent and -independent vascular reactivity. This effect may be influenced by vascular oxidative stress and is possibly exerted through a receptor-mediated mechanism.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/farmacologia , Glucose/metabolismo , Hiperinsulinismo/metabolismo , Síndrome Metabólica/metabolismo , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Humanos , Nitroprussiato/farmacologia , Estresse Oxidativo/efeitos dos fármacos
5.
Clin Endocrinol (Oxf) ; 77(4): 531-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22077984

RESUMO

INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) has been described in adult GH deficiency syndrome. Furthermore, chronic liver disease can be associated with significant changes in levels of IGF-I, GH-binding protein (GHBP), IGF-binding proteins (IGFBPs) and acid-labile subunit (ALS). However, the effect of liver steatosis on the GHBP production has not been investigated yet. AIM OF THE STUDY: To explore whether GH secretion and/or levels of IGF-I, IGFBP-3, ALS and GHBP could be altered in obese patients in relation to the presence of liver steatosis. MATERIALS AND METHODS: A total of 115 obese patients (BMI > 30) were enrolled in the protocol (65 patients with liver steatosis and 50 age- and BMI-matched controls). In all patients, the following parameters were studied: serum levels of glucose, insulin, the HOMA index, IGF-I, GHBP, IGFBP-3, ALS and GH after GHRH and arginine stimulation test. RESULTS: As expected, patients with NAFLD had blood glucose, insulin, HOMA-R significantly higher than controls, indicating a more severe insulin-resistance state in NAFLD. Furthermore, patients with NAFLD had higher levels of GHBP and IGFBP-3 and lower GH peak and IGF-I levels as compared to controls. No difference was found in ALS levels between the groups. In a multivariate analysis, GHBP was positively associated with hepatic steatosis while IGF-1 was negatively associated with hepatic steatosis. CONCLUSIONS: This study demonstrates that in patients with NAFLD, the GHBP levels are increased, and that the GH/IGF-I axis is significantly altered probably leading to reduced IGF-I bioavailability at tissue level.


Assuntos
Proteínas de Transporte/sangue , Fígado Gorduroso/sangue , Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Adulto , Glicemia/metabolismo , Estudos Transversais , Feminino , Glicoproteínas/sangue , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Obesidade/sangue
6.
J Nutr Biochem ; 22(3): 259-68, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20573495

RESUMO

It is now well accepted that oxysterols play important roles in the formation of atherosclerotic plaque, involving cytotoxic, pro-oxidant and proinflammatory processes. It has been recently suggested that tomato lycopene may act as a preventive agent in atherosclerosis, although the exact mechanism of such a protection is not clarified. The main aim of this study was to investigate whether lycopene is able to counteract oxysterol-induced proinflammatory cytokines cascade in human macrophages, limiting the formation of atherosclerotic plaque. Therefore, THP-1 macrophages were exposed to two different oxysterols, such as 7-keto-cholesterol (4-16 µM) and 25-hydroxycholesterol (2-4 µM), alone and in combination with lycopene (0.5-2 µM). Both oxysterols enhanced pro-inflammatory cytokine [interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor α) secretion and mRNA levels in a dose-dependent manner, although at different extent. These effects were associated with an increased reactive oxygen species (ROS) production through an enhanced expression of NAD(P)H oxidase. Moreover, a net increment of phosphorylation of extracellular regulated kinase 1/2, p-38 and Jun N-terminal kinase and of nuclear factor kB (NF-κB) nuclear binding was observed. Lycopene prevented oxysterol-induced increase in pro-inflammatory cytokine secretion and expression. Such an effect was accompanied by an inhibition of oxysterol-induced ROS production, mitogen-activated protein kinase phosphorylation and NF-κB activation. The inhibition of oxysterol-induced cytokine stimulation was also mimicked by the specific NF-κB inhibitor pyrrolidine dithiocarbamate. Moreover, the carotenoid increased peroxisome proliferator-activated receptor γ levels in THP-1 macrophages. Taken all together, these data bring new information on the anti-atherogenic properties of lycopene, and on its mechanisms of action in atherosclerosis prevention.


Assuntos
Carotenoides/farmacologia , Citocinas/biossíntese , Hidroxicolesteróis/efeitos adversos , Cetocolesteróis/efeitos adversos , Macrófagos/metabolismo , NF-kappa B/metabolismo , PPAR gama/metabolismo , Linhagem Celular , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Licopeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidases/metabolismo , NF-kappa B/genética , PPAR gama/genética , Fosforilação , Placa Aterosclerótica/metabolismo , Ligação Proteica , RNA Mensageiro/análise , Espécies Reativas de Oxigênio/análise , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
7.
Pituitary ; 14(4): 351-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19152032

RESUMO

Prolactinomas in males can be voluminous macroadenomas invading the surrounding structures. Medical therapy with dopamine agonists (the treatment of choice for these tumours) may be ineffective in the case of pharmacological resistance. In such cases, even surgical and/or radiation therapy cannot be curative due to the invasive potential of the adenoma. Hence, the appropriate therapeutic approach for these tumours is still a relevant clinical problem for endocrinologists. We report the history of an adolescent male who was diagnosed with a large invasive macroprolactinoma in 2002. He had severe bitemporal hemianopsia and hypopituitarism; prolactin levels at diagnosis were higher than 8,000 ng/ml. Medical therapy with cabergoline was initiated and resulted in decreased prolactin levels but not complete normalisation (maximal tolerated dose 3 mg/day). However, due to the worsening of the visual defect, the patient was operated in July 2004 through the trans-nasal approach and 2 years later through both the transcranial and the transphenoidal approaches. After the second surgery, a significant reduction of tumour mass was obtained. Immunohistochemistry for somatostatin receptors (sstr) subtypes showed a positive staining with the anti-sstr5 antibody. A scintigraphy with 111In-pentetreotide (Octreoscan) revealed a very intense tracer uptake in the sellar region. The administration of long-acting octreotide was initiated. After 12 months of therapy, prolactin levels normalised for the first time. Pituitary MRI did not reveal any tumor progression during a 2-year follow-up. This is a case of an invasive dopamine-resistant macroprolactinoma that was successfully controlled by extensive surgery and combined treatment with cabergoline and octreotide. The expression and functionality of sstr should be investigated in these tumours since a combined therapy with cabergoline and octreotide may be a good therapeutic course of action for select cases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Ergolinas/administração & dosagem , Octreotida/administração & dosagem , Neoplasias Hipofisárias/tratamento farmacológico , Prolactinoma/tratamento farmacológico , Adolescente , Antineoplásicos Hormonais/administração & dosagem , Cabergolina , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Masculino , Resultado do Tratamento
8.
Diabetes Care ; 31(7): 1439-41, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18390795

RESUMO

OBJECTIVE: Obesity is associated with chronic inflammation due to overproduction of proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha. We assessed the effects of TNF-alpha neutralization by infliximab on vascular reactivity during hyperinsulinemia in obesity-related metabolic syndrome. RESEARCH DESIGN AND METHODS: Vascular responses to intra-arterial infusion of acetylcholine (ACh) and sodium nitroprusside (SNP) were assessed in patients with metabolic syndrome, before and after administration of infliximab. RESULTS: Patients had blunted vasodilator responses to ACh and SNP during hyperinsulinemia compared with control subjects; a potentiation of the responsiveness to both ACh and SNP, however, was observed in patients following infliximab. The antioxidant vitamin C improved the vasodilator response to ACh in patients with metabolic syndrome, but its effect was not further enhanced by concurrent administration of infliximab. CONCLUSIONS: TNF-alpha neutralization ameliorates vascular reactivity in metabolic syndrome during hyperinsulinemia, likely in relation to decreased oxidative stress, thereby suggesting an involvement of inflammatory cytokines in vascular dysfunction of these patients.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Hiperinsulinismo/fisiopatologia , Síndrome Metabólica/fisiopatologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Análise de Variância , Glicemia/metabolismo , Colesterol/sangue , Humanos , Hiperinsulinismo/tratamento farmacológico , Infliximab , Síndrome Metabólica/tratamento farmacológico , Nitroprussiato/farmacologia , Valores de Referência , Triglicerídeos/sangue
9.
Ann N Y Acad Sci ; 1069: 257-62, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16855152

RESUMO

Testosterone (T), sex hormone-binding globulin, (SHBG), dehydroepiandrosterone sulfate (DHEAS), and prolactin (Prl) serum levels were measured by electrochemiluminescense immunoassay (ECLIA) in 39 patients with systemic sclerosis (SSc) and compared with serum hormonal levels in control subjects matched for sex and reproductive status. A possible relationship with disease duration and disease severity was examined. Our data show an altered androgen and prolactin (Prl) status in SSc patients, in most cases related to disease duration and disease severity score. We can hypothesize that hormonal dysregulation is a consequence of the chronicity of the disease. The altered hormonal status could result in relative immunological hyperactivity contributing to enhance tissue damage and disease severity.


Assuntos
Androgênios/sangue , Prolactina/sangue , Escleroderma Sistêmico/sangue , Escleroderma Sistêmico/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esteroides/sangue
10.
Menopause ; 13(3): 462-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16735943

RESUMO

OBJECTIVE: Osteoarthritis and osteoporosis are two major health problems affecting postmenopausal women. Epidemiological observations seem to demonstrate a possible inverse relationship between osteoarthritis and osteoporosis. Erosive osteoarthritis (EOA) of the hand is a destructive form of primary osteoarthritis. This study evaluated bone mineral density and bone metabolism changes in erosive and nonerosive hand osteoarthritis women. DESIGN: Fifty-five women (mean age, 59 years; body mass index, 23 +/- 1.4 kg/m) who had been postmenopausal for an average of 9 years and who presented with hand osteoarthritis according to American College of Rheumatology criteria were enrolled in the study; 15 women showed clinical and radiological evidence of hand EOA. Twenty women matched for age, age at menopause, and body mass index formed the control group. Bone mineral density (g/cm) was measured at the hip and lumbar spine using dual-energy x-ray absorptiometry. Serum and urinary calcium and phosphate, serum 25-hydroxyvitamin D, parathyroid hormone, osteocalcin, and urinary breakdown products of bone matrix (CrossLaps) were analyzed. RESULTS: Women with hand EOA had a statistically significant lower T- and Z-score L2-L4 value than non-hand EOA women and controls (P < 0.01). Moreover, postmenopausal women with hand EOA had higher significant percentage of osteoporosis at lumbar spine when compared with non-hand EOA postmenopausal women and controls. Any statistically significant difference in osteocalcin and CrossLaps serum levels was noted among women with hand EOA, hand osteoarthritis, and controls. CONCLUSIONS: Our data suggest that postmenopausal women with clinical and radiological EOA are at risk for development of osteoporosis.


Assuntos
Osteoartrite/epidemiologia , Osteoporose Pós-Menopausa/epidemiologia , Densidade Óssea , Reabsorção Óssea , Estudos de Casos e Controles , Colágeno , Feminino , Fêmur/diagnóstico por imagem , Mãos/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Osteoartrite/sangue , Osteoartrite/diagnóstico por imagem , Osteoartrite/etiologia , Osteoartrite/fisiopatologia , Osteocalcina/sangue , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/diagnóstico por imagem , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/fisiopatologia , Radiografia
11.
Fertil Steril ; 81(4): 1047-54, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15066462

RESUMO

OBJECTIVE: To determine the effect of naltrexone (an opiate receptor blocker) on insulin metabolism in postmenopausal women with different insulinemic patterns. DESIGN: Randomized placebo-controlled study. SETTING: Academic research environment. PATIENT(S): Forty-one healthy normoinsulinemic or hyperinsulinemic postmenopausal women. INTERVENTION(S): Oral glucose tolerance test (OGTT) before and after 5 weeks of the opioid antagonist (naltrexone, 50 mg/d orally) or the placebo administration; euglycemic-hyperinsulinemic glucose clamp. MAIN OUTCOME MEASURE(S): Glucose, insulin, and C-peptide plasma levels assessed in fasting condition and during the OGTT. Insulin sensitivity was calculated as total body glucose utilization. RESULT(S): Naltrexone reduced fasting and stimulated insulin response to the glucose load while inducing a significant improvement of the hepatic extraction, only in the hyperinsulinemic patients. No differences were found in the C-peptide pancreatic secretion and in the peripheral insulin sensitivity. No net change in the glycoinsulinemic metabolism was observed in normoinsulinemic patients or in placebo-controlled normoinsulinemic and hyperinsulinemic subjects. CONCLUSION(S): Similar to that reported in premenopausal women, endogenous opioid peptides are involved in the modulation of glycoinsulinemic metabolism in postmenopause. Through a prevalent action on liver insulin metabolism, without any clear improvement of insulin resistance and pancreatic beta-cell function, the chronic administration of naltrexone appears to reduce the hyperinsulinemia in those women with an exaggerated insulin response to the OGTT.


Assuntos
Hiperinsulinismo/tratamento farmacológico , Naltrexona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Pós-Menopausa , Glicemia/análise , Peptídeo C/sangue , Jejum/sangue , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Hiperinsulinismo/sangue , Insulina/sangue , Resistência à Insulina , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
12.
Hum Reprod ; 19(4): 1031-5, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15016776

RESUMO

BACKGROUND: Higher than normal homocysteine levels are associated with an increased incidence of adverse cardiovascular events in post-menopausal women, perhaps via hyperhomocysteinaemia-induced vascular endothelial damage. Because folic acid supplementation reduces homocysteine levels, we attempted to evaluate whether folic acid supplementation may affect endothelial function in post-menopausal women. METHODS: Brachial artery flow-mediated dilatation (endothelium-dependent) and nitroglycerin-induced dilatation (endothelium-independent) before and after a methionine load were analysed in 15 healthy post-menopausal women. Plasma levels of folate, homocysteine, glucose, insulin and lipids were measured, as was blood pressure. All studies were repeated after 1 month supplementation with 7.5 mg/day of folic acid. RESULTS: After folate, endothelial function rose 37% over pre-folic acid supplementation value (P < 0.001), and flow-mediated dilation before folic acid was reduced by 62% subsequent to methionine loading (P < 0.0001); this reduction was still present after folic acid, but was only 19% (P < 0.001). Nitroglycerin-induced dilatation did not change in response to methionine loading before or after folic acid supplementation. Among the other cardiovascular risk factors studied, only high-density lipoprotein (HDL)-cholesterol and low-density lipoprotein (LDL)-cholesterol showed significant changes after folic acid supplementation, with a 6% increase (P < 0.03) and a 9% decrease (P < 0.03) respectively. CONCLUSIONS: Although preliminary, these results indicate that folic acid supplementation may improve endothelial function and lipid profile in post-menopausal women, thus contributing to reduce their cardiovascular risk.


Assuntos
Artéria Braquial/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Ácido Fólico/farmacologia , Metionina/farmacologia , Nitroglicerina/farmacologia , Pós-Menopausa/fisiologia , Vasodilatação/efeitos dos fármacos , Artéria Braquial/fisiologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/sangue
13.
Fertil Steril ; 78(5): 994-1000, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12413983

RESUMO

OBJECTIVE: To investigate the effect of naloxone, an opioid receptor antagonist, on the release of growth hormone (GH) induced by the growth hormone-releasing hormone (GHRH) in normal-weight and obese women with PCOS in relation to feeding. DESIGN: Prospective clinical study. SETTING: Academic research center. PATIENT(S): Seventeen women with PCOS (10 who were normal weight and 7 who were obese) and 14 control women (7 who were normal weight and 7 who were obese). INTERVENTION(S): A GHRH test (50 microg i.v.) and, on a different day, a GHRH test during a naloxone infusion (1.6 mg/h) during fasting. The same tests were repeated after a standard meal. MAIN OUTCOME MEASURE(S): GH response to GHRH (expressed as the area under the curve [AUC]) in different experimental conditions. RESULT(S): All normal-weight women showed a significantly higher AUC-GH compared with obese women in the fasting state. Normal-weight controls had a decrease in GH response to GHRH after feeding, and naloxone did not reverse the decrease. In obese controls, feeding increased the GH response but naloxone induced a decrease in the AUC. In fasting, normal-weight women with PCOS, naloxone significantly decreased the AUC-GH; in these patients, food intake induced an inhibition of GH response to GHRH, reversed by naloxone infusion. In obese PCOS patients, GH levels did not increase significantly after GHRH stimulation, either in the fasting state or after a meal, and naloxone did not affect these responses. CONCLUSION(S): Factors other than obesity and insulin may be involved in disruption of GH secretion in women with PCOS.


Assuntos
Ingestão de Alimentos/fisiologia , Hormônio Liberador de Hormônio do Crescimento/uso terapêutico , Hormônio do Crescimento Humano/metabolismo , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Adulto , Área Sob a Curva , Peso Corporal , Jejum/fisiologia , Feminino , Humanos , Obesidade/complicações , Obesidade/patologia , Síndrome do Ovário Policístico/complicações , Estudos Prospectivos , Valores de Referência
14.
Fertil Steril ; 78(5): 1017-24, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12413987

RESUMO

OBJECTIVE: To evaluate the influence of the opioid system on glyco-regulation in postmenopausal women before and after hormone replacement therapy (HRT). DESIGN: Prospective nonrandomized clinical study. SETTING: Academic research environment. PATIENT(S): Twenty-one healthy normo- or hyperinsulinemic postmenopausal women. INTERVENTION(S): Oral glucose tolerance test (OGTT) (saline study), OGTT with IV injection of naloxone (naloxone study), and hyperinsulinemic euglycemic clamp performed before treatment, after 12 weeks of estrogen replacement therapy (ERT), and after 12 additional weeks of estro-progestin combined therapy (i.e., HRT). MAIN OUTCOME MEASURE(S): Glucose, insulin, and c-peptide plasma levels assessed in fasting condition and during the two OGTTs (area under the curve [AUC]). Evaluation of fractional hepatic insulin extraction (FHIE) and peripheral sensitivity to insulin. RESULT(S): At baseline, there is a greater increase of the FHIE and a more significant reduction of the insulin AUC in the hyperinsulinemic patients during the naloxone study compared with the saline study. In these women, ERT enhanced the c-peptide AUC and improved the FHIE; naloxone infusion mainly increased these two parameters. HRT did not induce any further change. CONCLUSION(S): Endogenous opioid peptides are involved in the modulation of carbohydrate metabolism in menopause in hyperinsulinemic patients more than in other patients. The favorable changes of the glyco-insulinemic metabolism induced by HRT may be partially due to the induction of the opioidergic activity.


Assuntos
Terapia de Reposição de Estrogênios , Hiperinsulinismo/tratamento farmacológico , Hiperinsulinismo/metabolismo , Antagonistas da Insulina/uso terapêutico , Insulina/metabolismo , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Pós-Menopausa , Área Sob a Curva , Peptídeo C/sangue , Sinergismo Farmacológico , Feminino , Teste de Tolerância a Glucose , Humanos , Secreção de Insulina , Pessoa de Meia-Idade , Estudos Prospectivos , Cloreto de Sódio/uso terapêutico
15.
Ann N Y Acad Sci ; 966: 508-12, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12114312

RESUMO

Prolactin (PRL) and glucocorticoids are hormones involved in the regulation of the immune system. Rheumatoid arthritis (RA) is an inflammatory condition that presents a diurnal rhythm of disease activity. PRL/cortisol ratio, and IL-1beta and TNF-alpha levels were determined in patients with RA and in control subjects at 0600, 1000, 1400, 1800, 2200, and 0200 hours. In patients with RA we observed higher PRL/cortisol ratio at 0200 hours, whereas IL-1beta and TNF-alpha reached their highest serum levels at 0200 and 0600 hours. In patients with RA we observed an imbalance in favor of proinflammatory hormones as opposed to levels of antiinflammatory hormones during nocturnal hours together with increased levels of IL-1beta and TNF-alpha of the diurnal rhythm of disease activity.


Assuntos
Artrite Reumatoide/sangue , Doenças Autoimunes/sangue , Hidrocortisona/sangue , Prolactina/sangue , Artrite Reumatoide/imunologia , Artrite Reumatoide/fisiopatologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/fisiopatologia , Índice de Massa Corporal , Ritmo Circadiano , Feminino , Humanos , Hidrocortisona/metabolismo , Hiperprolactinemia/sangue , Hiperprolactinemia/etiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Interleucina-1/sangue , Pessoa de Meia-Idade , Neuroimunomodulação , Sistema Hipófise-Suprarrenal/fisiopatologia , Pós-Menopausa/sangue , Prolactina/metabolismo , Taxa Secretória , Fator de Necrose Tumoral alfa/análise
16.
Metabolism ; 51(2): 137-43, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11833038

RESUMO

To assess the effect of transdermal estrogen substitution on the hypothalamic-pituitary-adrenal (HPA) axis responsiveness/sensitivity and the impact of the antrophometric characteristics on these parameters, 20 postmenopausal women seeking treatment for the relief of postemenopausal symptoms were studied. They received transdermal 50 microg/d estradiol for 12 weeks (estrogen replacement therapy [ERT]). Patients were classified as low waist-to-hip ratio (WHR) (peripheral fat distribution women; n = 12) and high WHR (central fat distribution women; n = 8) according to the cut-off value of 0.85. Plasma hormone and lipid concentration were assessed at baseline and after 12 weeks of treatment. Results were compared with a group of 8 placebo-treated patients who served as controls. Corticotropin (ACTH) and cortisol (F) were expressed as fasting values, area under the curve (AUC), and time course over 90 minutes after corticotropin-releasing hormone (CRH) intravenous (IV) bolus (1 microg/kg body weight [BW]). Adrenal sensitivity to CRH stimulus was expressed as time course over 90 minutes and AUC of the F/ACTH molar ratio. The plasma F levels in response to ACTH stimulation did not change after ERT; however, a highly significant improvement of adrenal sensitivity was observed (P <.01). In fact, estrogen treatment significantly decreased the amount of ACTH produced after CRH stimulation, both as absolute time course and AUC (P <.01). No significant change was observed in controls. Considering body fat distribution, the high WHR group showed higher ACTH (P <.01), lower F/ACTH values, and superimposable F plasma values compared with the low WHR group. Estrogen treatment induced a significant ACTH reduction after CRH (P <.01) only in the high WHR group, whereas cortisol response was similar in both groups both before and after treatment. A significant negative correlation was found between WHR and adrenal sensitivity before treatment. ERT significantly improved adrenal sensitivity only in the low WHR group (P <.01). These data suggest that different mechanisms can prevail in the control of the HPA axis in menopause. Estrogens could exert different effects on the hypothalamic-pituitary axis, as well as on adrenal function, and these changes seem to be partially dependent on the pattern of body fat distribution.


Assuntos
Tecido Adiposo , Hormônio Adrenocorticotrópico/fisiologia , Composição Corporal , Hormônio Liberador da Corticotropina/fisiologia , Estradiol/administração & dosagem , Hidrocortisona/fisiologia , Pós-Menopausa , Administração Cutânea , Glândulas Suprarrenais/fisiologia , Estradiol/fisiologia , Feminino , Humanos , Sistema Hipotálamo-Hipofisário , Placebos
17.
Arq. gastroenterol ; 23(4): 242-5, out.-dez. 1986. tab
Artigo em Português | LILACS | ID: lil-42503

RESUMO

Utilizando-se o método ELISA (Enzyme Linked Immuno Sorbent Assay) para detecçäo de rotavírus em fezes de crianças com "doença diarréica aguda infecciosa" internadas na enfermaria de diarréia do Hospital Infantil Menino Jesus (SP), obtivemos 12 casos positivos para rotavírus em 70 crianças estudadas no período de março de 1983 a junho de 1984 (17,1% de positividade para o rotavírus). Além desses casos, encontramos o rotavírus em dois casos associados com bactéria enteropatogênica (Shighella). A idade das crianças positivas para o rotavírus variou de 2 meses a 4 anos e meio. Todas as crianças positivas para o rotavírus apresentaram vômitos e febre, e a relaçäo com infecçäo de vias aéreas superiores foi significante (dois casos). A maioria dos casos positivos foi colhida em dias de clima frio ou temperado. Apenas uma criança era eutrófica


Assuntos
Lactente , Pré-Escolar , Humanos , Diarreia Infantil/microbiologia , Infecções por Rotavirus/diagnóstico , Rotavirus/isolamento & purificação , Brasil , Diarreia/microbiologia , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia
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