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1.
Eur J Endocrinol ; 181(2): R73-R105, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31242462

RESUMO

In the currently overwhelming era of polypharmacy, the balance of the dynamic and delicate endocrine system can easily be disturbed by interfering pharmaceutical agents like medications. Drugs can cause endocrine abnormalities via different mechanisms, including direct alteration of hormone production, changes in the regulation of the feedback axis, on hormonal transport, binding and signaling, as well as similar changes to counter-regulatory hormone systems. Furthermore, drugs can interfere with the hormonal assays, leading to erroneous laboratory results that disorientate clinicians from the right diagnosis. The purpose of this review is to cover a contemporary topic, the drug-induced endocrinopathies, which was presented in the monothematic annual Combo Endo Course 2018. This challenging part of endocrinology is constantly expanding particularly during the last decade, with the new oncological therapeutic agents, targeting novel molecular pathways in the process of malignancies. In this new context of drug-induced endocrine disease, clinicians should be aware that drugs can cause endocrine abnormalities via different mechanisms and mimic a variety of clinical scenarios. Therefore, it is extremely important for clinicians not only to promptly recognize drug-induced hormonal and metabolic abnormalities, but also to address the therapeutic issues for timely intervention.


Assuntos
Diabetes Mellitus/metabolismo , Doenças do Sistema Endócrino/induzido quimicamente , Doenças do Sistema Endócrino/patologia , Sistema Endócrino/patologia , Endocrinologia/métodos , Animais , Diabetes Mellitus/diagnóstico , Sistema Endócrino/efeitos dos fármacos , Humanos
2.
Nutr Metab Cardiovasc Dis ; 27(10): 881-889, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28851556

RESUMO

BACKGROUND AND AIMS: Visceral adiposity index (VAI) has been proposed as a marker of visceral adipose tissue accumulation/dysfunction. Our aim was to evaluate potential associations between the VAI and the 10-year cardiovascular disease (CVD) incidence. METHODS AND RESULTS: During 2001-2002, 3042 Greek adults (1514 men; age: ≥18 years) without previous CVD were recruited into the ATTICA study, whilst the 10-year study follow-up was performed in 2011-2012, recording the fatal/non-fatal CVD incidence in 2020 (1010 men) participants. The baseline VAI scores for these participants were calculated based on anthropometric and lipid variables, while VAI tertiles were extracted for further analyses. During the study follow-up a total of 317 CVD events (15.7%) were observed. At baseline, the participants' age and the prevalence of hypertension, diabetes, hypercholesterolemia and metabolic syndrome increased significantly across the VAI tertiles. After adjusting for multiple confounders, VAI exhibited a significantly independent positive association with the 10-year CVD incidence (OR = 1.05, 95%CI: 1.01, 1.10), whereas the association of the body mass index (HR = 1.03, 95%CI: 0.99, 1.08), or the waist circumference (HR = 1.01, 95%CI: 0.99, 1.02) was less prominent. Sex-specific analysis further showed that VAI remained significantly predictive of CVD in men alone (HR = 1.06, 95%CI: 1.00, 1.11) but not in women (HR = 1.06, 95%CI: 0.96, 1.10). CONCLUSIONS: Our findings show for the first time in a large-sample, long-term, prospective study in Europe that the VAI is independently associated with elevated 10-year CVD risk, particularly in men. This suggests that the VAI may be utilized as an additional indicator of long-term CVD risk for Caucasian/Mediterranean men without previous CVD.


Assuntos
Adiposidade , Doenças Cardiovasculares/epidemiologia , Gordura Intra-Abdominal/fisiopatologia , Obesidade Abdominal/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/fisiopatologia , Comorbidade , Feminino , Grécia/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/diagnóstico , Obesidade Abdominal/mortalidade , Obesidade Abdominal/fisiopatologia , Prevalência , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Adulto Jovem
5.
Horm Metab Res ; 39(10): 758-63, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17952840

RESUMO

Visfatin, is a new adipokine, highly expressed in the visceral fat of both mice and humans. To examine whether visfatin is expressed in human peripheral monocyte-enriched mononuclear cells and whether its expression is altered in type 2 diabetes (DM2), we compared 24 DM2 women [17 overweight (BMI >25) and 7 lean (BMI<25)] to 26 healthy women (14 overweight and 12 lean), all premenopausal. Relative visfatin mRNA levels were significantly higher (approximately 3-fold) in DM2 compared to healthy control women (p<0.02), independently of the presence of overweight/obesity. Mononuclear TNF-alpha and IL-6 mRNA expression was also elevated in DM2 compared to control women (p=0.001 and p=0.004, respectively), an increase observed in both lean and overweight DM2 women. By contrast, circulating visfatin, TNF-alpha, and IL-6 levels showed no difference between DM2 and control women, while adiponectin plasma levels were significantly decreased in the DM2 women (p<0.001). Circulating visfatin and TNF-alpha levels did not differ either between the lean and the overweight subgroups of DM2 and control women, while IL-6 plasma levels were significantly higher in both overweight subgroups compared to their lean counterparts. In conclusion, visfatin, TNF-alpha, and IL-6 mRNA expressions are increased in peripheral mononuclear-monocytic cells from women with type 2 diabetes, independent of their BMI, which may enhance the effects of their adipose-derived levels and may contribute to the increased insulin resistance and atherogenic risk of these patients.


Assuntos
Diabetes Mellitus Tipo 2/genética , Interleucina-6/genética , Leucócitos Mononucleares/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Interleucina-6/sangue , Interleucina-6/metabolismo , Leucócitos Mononucleares/patologia , Pessoa de Meia-Idade , Nicotinamida Fosforribosiltransferase/sangue , Nicotinamida Fosforribosiltransferase/metabolismo , Sobrepeso/sangue , Sobrepeso/complicações , Sobrepeso/genética , Sobrepeso/metabolismo , RNA Mensageiro/metabolismo , Magreza/sangue , Magreza/genética , Magreza/metabolismo , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
6.
Horm Metab Res ; 39(6): 430-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17578760

RESUMO

Stress can be defined as a state of threatened homeostasis or disharmony. An intricate repertoire of physiologic and behavioral responses is mobilized under stressful situations forming the adaptive stress response that aims to reestablish the challenged body equilibrium. The hypothalamic-pituitary-adrenal axis and the central and peripheral components of the autonomic nervous system constitute the two main pillars that subserve the vital functions of the stress system. Chronic stress represents a prolonged threat to homeostasis that can progressively lead to a deleterious overload with various complications caused by both the persistent stressor and the detrimental prolongation of the adaptive response. Recent data indicate that chronic stress is associated to derangement of metabolic homeostasis that contributes to the clinical presentation of visceral obesity, type 2 diabetes, atherosclerosis and metabolic syndrome. Notably, indices of stress in the modern western societies correlate with the increasing incidence of both obesity and the metabolic syndrome which have reached epidemic proportions over the past decades. The pathogenetic mechanisms that accommodate these correlations implicate primarily the chronic hyperactivation of the HPA axis under prolonged stress, which favors accumulation of visceral fat, and VICE VERSA; obesity constitutes a chronic stressful state that may cause HPA axis dysfunction. In addition, obesity is being now recognized as a systemic low grade inflammatory state that contributes to the derangement of the metabolic equilibrium, implicating the adipocyte secretion of adipokines to the pathogenesis of several components of the metabolic syndrome. Understanding the mechanisms that mediate the documented reciprocal relationships between stress and metabolic homeostasis will hopefully provide novel insights to the pathophysiology of obesity, type 2 diabetes, and their cardiometabolic complications, and will help the quest for more specific and effective therapeutic interventions.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Obesidade/etiologia , Estresse Psicológico/complicações , Estresse Psicológico/etiologia , Animais , Encéfalo/fisiologia , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia
7.
Int J Obes (Lond) ; 31(4): 569-77, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17325689

RESUMO

In 2005, for the first time in European history, an extraordinary Expert panel named 'The BSCG' (Bariatric Scientific Collaborative Group), was appointed through joint effort of the major European Scientific Societies which are active in the field of obesity management. Societies that constituted this panel were: IFSO - International Federation for the Surgery of Obesity, IFSO-EC - International Federation for the Surgery of Obesity - European Chapter, EASO - European Association for Study of Obesity, ECOG - European Childhood Obesity Group, together with the IOTF (International Obesity Task Force) which was represented during the completion process by its representative. The BSCG was composed not only of the top officers representing the respective Scientific Societies (four acting presidents, two past presidents, one honorary president, two executive directors), but was balanced with the presence of many other key opinion leaders in the field of obesity. The BSCG composition allowed the coverage of key disciplines in comprehensive obesity management, as well as reflecting European geographical and ethnic diversity. This joint BSCG expert panel convened several meetings which were entirely focused on guidelines creation, during the past two years. There was a specific effort to develop clinical guidelines, which will reflect current knowledge, expertise and evidence based data on morbid obesity treatment.


Assuntos
Cirurgia Bariátrica , Obesidade/cirurgia , Adolescente , Adulto , Fatores Etários , Cirurgia Bariátrica/métodos , Índice de Massa Corporal , Criança , Contraindicações , Europa (Continente) , Humanos , Cooperação Internacional , Absorção Intestinal/fisiologia , Pessoa de Meia-Idade , Obesidade/dietoterapia , Equipe de Assistência ao Paciente , Cuidados Pré-Operatórios/métodos , Falha de Tratamento
8.
Ann N Y Acad Sci ; 1083: 214-38, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17148742

RESUMO

Chronic inflammation has been suggested to play an important role in metabolic diseases, such as atherothrombosis and type 2 diabetes. A lot of research has focused on the immunomodulatory effects of several nutrients, such as fatty acids, antioxidants, carbohydrates, specific amino acids, micronutrients, and alcohol, which play a crucial role in the maintenance of an "optimal" immune response. In addition, specific dietary patterns, such as the Mediterranean diet, are evolving as protective against cardiovascular disease, because of their anti-inflammatory properties. In this article, the existing data concerning the nutrients' pro- and anti-inflammatory properties are presented, as well as dietary patterns that could protect from chronic inflammation and its metabolic and atherothrombotic complications.


Assuntos
Dieta Mediterrânea , Inflamação/prevenção & controle , Antioxidantes/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/prevenção & controle , Gorduras na Dieta/metabolismo , Suplementos Nutricionais , Ácidos Graxos Ômega-3/metabolismo , Humanos , Inflamação/imunologia
9.
Horm Metab Res ; 36(8): 559-63, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15326566

RESUMO

AIM: To study the effect of two different isoenergetic meals, one rich in carbohydrates and one rich in fat, on plasma active ghrelin levels in lean or obese subjects. METHODS: Eight obese and eight lean women, strictly matched for age, were fed two isoenergetic meals of different composition, one rich in fat and one rich in carbohydrates (CHO), on separate days. Plasma active ghrelin levels were measured just before and at 1, 2 and 3 hours after meal consumption. RESULTS: Overall, plasma active ghrelin levels were significantly lower in the obese compared to the lean women (71.7 +/- 29.7 vs. 222.2 +/- 127.2 pmol/liter respectively, p < 0.0001). Furthermore, ghrelin levels decreased significantly by 30 % from baseline values in the lean subjects in the first hour after the CHO-rich meal (mean difference +/- SD): -66.2 +/- 49.0 pmol/liter (p = 0.03), returning to near-baseline levels by 2 hours, while no significant change was observed in the obese subjects. After the fat-rich meal, active ghrelin levels did not change significantly in either group (p > 0.05). CONCLUSIONS: A fat-rich meal does not suppress plasma active ghrelin levels in either lean or obese women. Moreover, in obese, unlike lean women, a high carbohydrate meal also fails to suppress plasma ghrelin levels, which are already quite low. This suggests that ghrelin-induced satiety mechanisms may be compromised in these subjects.


Assuntos
Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Obesidade/sangue , Hormônios Peptídicos/sangue , Magreza/sangue , Adulto , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Metabolismo Energético , Feminino , Grelina , Humanos , Pessoa de Meia-Idade , Obesidade/metabolismo , Concentração Osmolar , Magreza/metabolismo
10.
Metabolism ; 52(11): 1426-32, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14624401

RESUMO

Food ingestion can influence autonomic nervous system activity. This study compares the effects of 2 different isoenergetic meals on sympathetic nervous system (SNS) activity, assessed by heart rate variability (HRV) and plasma norepinephrine (NE) levels, in lean and obese women. Fifteen lean and 15 obese healthy women were examined on 2 occasions: after a carbohydrate (CHO)-rich and after a fat-rich test meal. Measurements of blood pressure, heart rate, resting energy expenditure, plasma glucose, lipids, insulin, leptin, and NE, as well as spectral analysis of the HRV, were performed at baseline and every 1 hour for 3 hours after meals. At baseline, obese women had higher SNS activity than lean controls (higher values of low-to-high frequency ratio [LF/HF], 1.52 +/- 0.31 v 0.78 +/- 0.13, P=.04; and plasma NE levels, 405.6 +/- 197.9 v 240.5 +/- 95.8 pg/mL, P<.0001). After the CHO-rich meal a greater increase in LF/HF and in plasma NE levels was observed in lean, compared to obese women (1.21 +/- 0.6 v 0.32 +/- 0.06, P=.04; and 102.9 +/- 35.4 v 38.7 +/- 12.3 pg/mL, P=.01, respectively), while no differences were observed after the fat-rich meal. Meal-induced thermogenesis was higher after the CHO-rich as compared to the fat-rich meal and was comparable between lean and obese women. Changes in HRV were not associated with the thermogenic response to the test meals. In conclusion, consumption of a CHO-rich meal causes greater cardiac SNS activation in lean than in obese women, while fat ingestion does not result in any appreciable change in either group. SNS activation does not appear to influence the thermic effect of the food in either lean or obese women.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Coração/fisiologia , Obesidade/fisiopatologia , Adulto , Área Sob a Curva , Sistema Nervoso Autônomo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Regulação da Temperatura Corporal/efeitos dos fármacos , Colesterol/sangue , Estudos Cross-Over , Metabolismo Energético/efeitos dos fármacos , Feminino , Coração/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Insulina/sangue , Leptina/sangue , Pessoa de Meia-Idade , Norepinefrina/sangue , Período Pós-Prandial/fisiologia , Troca Gasosa Pulmonar/fisiologia
11.
J Mol Med (Berl) ; 80(7): 406-11, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12110946

RESUMO

Familial glucocorticoid deficiency (FGD) is an autosomal recessive disorder characterized by a glucocorticoid adrenal insufficiency without mineralocorticoid deficiency. Mutations of the ACTH receptor (MC2-R) gene have been reported in some FGD cases, but only a few of them have been functionally studied. We reported clinical features and MC2-R gene analysis in three families. For each proband, an homozygous mutation was identified after amplification and sequencing of the whole intronless MC2-R gene. One mutation converted Val-142 located in the second intracellular loop to Leu. Another mutation in the sixth transmembrane domain converted Ala-233 to Pro. The last mutation converted the negatively charged Asp-103 in the first extracellular loop to an uncharged Asn. Functional studies of these mutations as well as the S120R mutation were performed after stable transfection of M3 cells and measurement of ACTH-induced cAMP production. For the S120R, V142L, and A233P mutated MC2-R, cAMP production curves were similar to that obtained with M3 parental cells, confirming that these mutations are responsible for the FGD in the affected patients. The D103N-mutated MC2-R had an impaired cAMP response to physiological doses of ACTH, but the maximal response at very high concentrations of ACTH was similar to that obtained for the wild-type MC2-R. All these results demonstrated clear relationships based on functional studies between MC2-R homozygous mutations and FGD phenotype.


Assuntos
Glucocorticoides/deficiência , Mutação , Receptores da Corticotropina/genética , Hormônio Adrenocorticotrópico/sangue , Sequência de Aminoácidos , Animais , Linhagem Celular , Pré-Escolar , AMP Cíclico/metabolismo , Feminino , Glucocorticoides/genética , Homozigoto , Humanos , Hidrocortisona/sangue , Lactente , Masculino , Camundongos , Linhagem , Estrutura Secundária de Proteína , Receptor Tipo 2 de Melanocortina , Receptores da Corticotropina/química , Síndrome , Turquia
12.
J Clin Endocrinol Metab ; 87(4): 1646-53, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11932296

RESUMO

The role of desmopressin, alone or in combination with CRH, in the differential diagnosis between Cushing's disease (CD) and ectopic ACTH secretion (EAS) still remains uncertain. Based on existing data, the desmopressin test is regarded as an alternative to the CRH stimulation test and, when given in combination with CRH, it has been suggested to completely discriminate between patients with CD and EAS. However, assessment of these tests has been limited in only a small number of patients with EAS. Desmopressin is a relatively specific V2 vasopressin receptor (V2R) agonist. Although expression of V3 vasopressin receptor (V3R) is common in tumors with EAS, the expression of V2R has not been extensively investigated. In the present study, we report our findings of the desmopressin and the combined CRH-desmopressin test in a series of patients with CD and EAS; also, the expression of V2R and V3R was investigated in tumors with EAS by a RT-PCR method. We assessed a cohort of 31 patients with ACTH-dependent Cushing's syndrome, including 26 patients with CD and five cases with histologically confirmed EAS. To avoid bias of predetermined criteria, univariate curves of the receiver operating characteristics (ROC) were constructed by plotting the sensitivity against 1-specificity at each level of the percent cortisol (F) and ACTH responses to these tests. Following desmopressin administration there was an overlap of the percent F and ACTH responses among patients with CD and EAS, and the area under the ROC curve for both these responses was not significantly different than that occurring by chance. This was also true for the percent F response following the combined CRH-desmopressin test. However, the area under the ROC curve for the percent ACTH rise following the combined test was significantly different; the point of the ROC curve closest to 1 corresponded to a percent ACTH rise of 218% (88% sensitivity and 80% specificity). Expression of V2R and V3R mRNA was investigated in four of the five excised tumors with EAS and revealed the presence of the V2R in all, whereas the V3R mRNA was expressed in three of these cases. In conclusion, in this series the desmopressin test produced a significant overlap of responses between CD and patients with EAS and, therefore, is of limited value in the differential diagnosis of the ACTH-dependent Cushing's syndrome. This is most probably due to the expression of the V2R in tumors with EAS. Moreover, following the combined CRH-desmopressin test only the ACTH but not the F responses were diagnostically useful, but still far from completely discriminating patients with CD and EAS.


Assuntos
Síndrome de ACTH Ectópico/diagnóstico , Hormônio Adrenocorticotrópico/fisiologia , Hormônio Liberador da Corticotropina , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/etiologia , Desamino Arginina Vasopressina , Síndrome de ACTH Ectópico/metabolismo , Adulto , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Receptores de Hormônio Liberador da Corticotropina/genética , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo
13.
Int J Obes Relat Metab Disord ; 25(7): 1018-26, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11443501

RESUMO

BACKGROUND: Tumor necrosis factor alpha (TNFalpha), a cytokine produced at inflammatory sites and in adipose tissue, is known primarily for its detrimental effects on insulin action. There is evidence to suggest that TNFalpha may also influence beta-cell function. Leptin is another adipose tissue-derived hormone that might also act on beta-cells. OBJECTIVE: We explored the independent and combined effects of TNFalpha and leptin upon basal and glucose-stimulated insulin transcription and secretion in the HIT-T15 pancreatic beta cell line. METHODS: Cells were cultured for 40 h in the presence of near-normal basal (7 mM) or high (16.7 mM) glucose and treated with either TNFalpha (1, 10 and 50 ng/ml) or leptin (10, 50 and 100 ng/ml) or both together. Insulin concentrations were measured by radioimmunoassay. Insulin mRNA levels were evaluated by a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) method, after normalization with beta-actin mRNA. RESULTS: TNFalpha significantly suppressed basal and glucose-stimulated insulin secretion and proinsulin mRNA transcription in a dose-dependent manner, an effect that was more powerful in the presence of high glucose. Leptin also inhibited dose-dependent insulin mRNA and protein at both glucose concentrations, but did not appear to further potentiate the suppressive effects of TNFalpha. CONCLUSION: TNFalpha suppresses both basal and glucose-stimulated insulin transcription and secretion in HIT-T15 cells, an effect that is enhanced significantly by high glucose. Leptin also independently inhibits basal and glucose-stimulated insulin secretion and transcription but does not modify TNFalpha effects. These effects might contribute to the abnormalities of glucose metabolism that characterize conditions of increased TNFalpha and/or leptin production.


Assuntos
Insulina/genética , Insulina/metabolismo , Leptina/farmacologia , RNA Mensageiro/análise , Fator de Necrose Tumoral alfa/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Glucose , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Radioimunoensaio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
14.
J Clin Endocrinol Metab ; 86(2): 583-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158012

RESUMO

Aberrant gastric inhibitory polypeptide (GIP) receptor expression in bilaterally hyperplastic adrenals or unilateral adrenal adenomas is a rare form of adrenal hyperfunction. So far, only few cases have been described. In all these cases, cortisol was the predominant steroid released in a food-dependent manner, leading to the development of non-ACTH-dependent Cushing's syndrome. In the present study, we describe a novel case of a GIP receptor-expressive adrenocortical adenomatous nodule, detected incidentally by computed tomography scanning in a 41-yr-old lady with hirsutism but no clinical signs of Cushing's syndrome, on physical examination. Hormonal investigations in morning fasting samples showed slightly elevated androgen levels, low-normal baseline cortisol, normal suppression of cortisol after dexamethasone administration, and ACTH levels that were not suppressed and did stimulate after CRH administration. The elevated urinary free cortisol excretion, in conjunction with an atypical cortisol diurnal rhythm, raised the possibility of an aberrant stimulation of cortisol production by the adrenal tumor. Further studies demonstrated food-dependent secretion of cortisol, which was abolished by prior octreotide administration. Notably, substantial amounts of adrenal androgens were also secreted after food consumption. Removal of the tumor resulted in undetectable cortisol and androgen levels that did not respond to food consumption. Histological examination of the excised tumor revealed an adrenocortical adenomatous nodule originating from the inner zona reticularis, consisting mainly of compact cells. A steroidogenic secretory pattern, indicating the concomitant release of adrenal androgens and cortisol, was also observed in vitro from tumor cells cultured in the presence of GIP. The in vitro secretory response to GIP was higher for the adrenal androgen DHEA, compared with cortisol. The expression of the GIP receptor in tumor cells, but not in the adjacent normal adrenal, was demonstrated by RT-PCR), using specific oligonucleotide probes for this receptor. In summary, we describe a patient with a GIP-expressive cortisol and androgen oversecreting adrenocortical nodule with the unusual presentation of hirsutism and not the typical clinical signs of Cushing's syndrome. It is of note that food intake in this patient provoked a substantial increase in both adrenal androgen and cortisol levels that, together with the histological appearance of this nodule, was compatible with a zona reticularis-derived tumor. Thus, aberrant expression of the GIP receptor does not exclusively involve cells of a zona fasciculata phenotype, as previously reported, but may also occur in other types of differentiated adrenocortical cells.


Assuntos
Adenoma/fisiopatologia , Neoplasias do Córtex Suprarrenal/fisiopatologia , Androgênios/metabolismo , Síndrome de Cushing/etiologia , Hirsutismo/etiologia , Hidrocortisona/metabolismo , Receptores dos Hormônios Gastrointestinais/genética , 17-alfa-Hidroxiprogesterona/sangue , Adenoma/sangue , Adenoma/patologia , Adenoma/cirurgia , Neoplasias do Córtex Suprarrenal/sangue , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Hormônio Adrenocorticotrópico/farmacologia , Adulto , Androgênios/sangue , Ritmo Circadiano , Síndrome de Cushing/fisiopatologia , Desidroepiandrosterona/sangue , Ingestão de Alimentos , Feminino , Hirsutismo/fisiopatologia , Humanos , Hidrocortisona/sangue , Octreotida , Receptores dos Hormônios Gastrointestinais/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Metabolism ; 49(12): 1537-41, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11145113

RESUMO

Leptin, the adipocyte-derived hormone, is secreted into the blood and regulates body weight via its receptors in the hypothalamus. Leptin receptors are also present in many peripheral tissues implicating leptin in the regulation of other body functions, including reproduction, liver and enteric metabolism, hematopoiesis, and immunity. Four splice variants of the leptin receptor have been identified in humans: the long isoform that has full intracellular signaling capacity and 3 shorter isoforms that differ in the length of their cytoplasmic tail. Here, we report the quantification by reverse transcriptase-polymerase chain reaction (RT-PCR) of the relative expression levels of the 2 major leptin receptor splice variants, the long (OB-RL) and the shortest membrane bound variant (OB-RS) in mononuclear cells from peripheral blood of 15 healthy human subjects (9 women and 6 men), with a body mass index (BMI) that ranged from 19.7 to 41.6. Both OB-RL and OB-RS were coexpressed in all mRNAs tested. However, the expression of the short form (OB-RS), was on average 8-fold higher than the expression of the long form (OB-RL) (120.8 +/- 12.9 v 14.6 +/- 3.0 relative intensity units, P < .001). The predominance of the short splice variant over the long one was apparent in all samples and ranged from 4- to 27-fold. There was no significant difference in the expression of either isoform between men and women. However, the relative expression of both OB-RS and OB-RL isoforms was significantly lower in the overweight (BMI > 26), compared with the lean subjects (BMI < 25) (78.8 +/- 9.1 and 6.2 +/- 1.1 v148.8 +/- 14.4 and 18.9 +/- 4.0 relative intensity units, respectively, P < .03) and was inversely correlated with the BMI and plasma leptin levels (P < .01). In conclusion, the expression of OB-RS and OB-RL leptin receptor isoforms appears to be reduced in human peripheral blood mononuclear cells from obese individuals, with OB-RS remaining the predominant leptin receptor isoform. This might have implications for the bioavailability and/or action of circulating leptin not only on these cells, but also on other target tissues.


Assuntos
Proteínas de Transporte/sangue , Monócitos/metabolismo , Receptores de Superfície Celular , Adulto , Índice de Massa Corporal , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , DNA Recombinante , Feminino , Variação Genética , Humanos , Leptina/sangue , Masculino , Isoformas de Proteínas/sangue , RNA Mensageiro/sangue , Receptores para Leptina , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Magreza
17.
Mol Genet Metab ; 71(4): 646-50, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11136558

RESUMO

Isolated glucocorticoid deficiency (IGD) is an autosomal recessive disorder characterized by primary adrenocortical insufficiency, without mineralocorticoid deficiency. Mutations of the ACTH receptor gene have been reported in several families with IGD. We have amplified and directly sequenced the entire intronless ACTH receptor gene in a new family with IGD. The proband was found to be compound heterozygote for two different point mutations, one in each allele: (a) a substitution (360C>G) which changed neutral serine at position 120 in the apolar third transmembrane domain of the receptor to a positively charged arginine (S120R), probably disrupting the ligand-binding site; and (b) a substitution (761A>G) changing tyrosine at position 254 to cysteine (Y254C) in the third extracellular loop of the receptor protein, that also likely disrupts its structure and interferes with ligand binding. Each of the two mutations in the proband has previously been described in a different family, S120R in compound heterozygosity with a stop codon (R201X) and Y254C in homozygote form. Thus, in the absence of in vitro functional studies, our findings confirm the pathogenetic role of the S120R and Y254C mutants in the development of resistance to ACTH.


Assuntos
Glândulas Suprarrenais/patologia , Glucocorticoides/deficiência , Mutação Puntual/genética , Receptores da Corticotropina/genética , Glândulas Suprarrenais/metabolismo , Negro ou Afro-Americano , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Sequência de Bases , Criança , Análise Mutacional de DNA , Feminino , Genes Recessivos , Heterozigoto , Humanos , Linhagem
18.
J Interferon Cytokine Res ; 19(11): 1271-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10574620

RESUMO

Inflammatory cytokines are soluble mediators of immune function that also regulate intermediate metabolism and several endocrine axes. To examine the effects of interleukin-6 (IL-6), the main circulating cytokine, on the hypothalamic-pituitary-testicular axis in men, we performed dose-response studies of recombinant human IL-6 (rHuIL-6) in normal volunteers. Increasing single doses of IL-6 (0.1, 0.3, 1.0, 3.0, and 10.0 microg/kg body weight) were injected subcutaneously into 15 healthy male volunteers (3 at each dose) in the morning. We measured the circulating levels of testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and sex hormone binding globulin (SHBG) at baseline and then at 24 h, 48 h, and 7 days after the IL-6 injection. LH and FSH levels were also measured half-hourly for the first 4 h after the IL-6 injection. All IL-6 doses were tolerated well and produced no significant adverse effects. Mean peak plasma IL-6 levels achieved after IL-6 administration were 8 +/- 1, 22 +/- 5, 65 +/- 22, 290 +/- 38, and 4050 +/- 149 pg/ml, respectively for the five doses. We observed no significant changes in plasma testosterone levels after the two smaller IL-6 doses. The three higher IL-6 doses, however, caused significant decreases in testosterone levels by 24 h, which persisted at 48 h and returned to baseline by 7 days. The higher testosterone suppression was after the 3.0 microg/kg dose, making the dose-response curve bell-shaped. There also appeared to be small but not significant increases in LH levels after the three higher IL-6 doses, which were not acute and seemed to follow temporally the testosterone decreases. The concurrent plasma levels of FSH and SHBG were not appreciably affected by any IL-6 dose. In conclusion, subcutaneous IL-6 administration, which caused acute elevations in circulating IL-6 levels of a similar magnitude to those observed in severe inflammatory and noninflammatory stress, induced prolonged suppression in testosterone levels in healthy men without apparent changes in gonadotropin levels. This suggests that IL-6 might induce persistent testicular resistance to LH action or suppression of Leydig cell steroidogenesis or both, with potential adverse effects on male reproductive function.


Assuntos
Interleucina-6/uso terapêutico , Hipófise/efeitos dos fármacos , Testículo/efeitos dos fármacos , Adulto , Relação Dose-Resposta a Droga , Hormônio Foliculoestimulante/sangue , Humanos , Interleucina-6/efeitos adversos , Hormônio Luteinizante/sangue , Masculino , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Valores de Referência , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue
19.
Metabolism ; 48(10): 1332-5, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10535400

RESUMO

Fat tissue is a significant source of endogenous tumor necrosis factor alpha (TNFalpha), the pluripotent cytokine that plays an important role as a mediator of the peripheral insulin resistance found in obesity. The majority of evidence for this role of TNFalpha is from studies in animal models of obesity. To explore further the role of TNFalpha in the pathogenesis of obesity-related insulin resistance in humans, we compared plasma levels of TNFalpha and the other main endocrine cytokine, interleukin-6 ([IL-6] both measured by enzyme-linked immunosorbent assay), in 26 obese women (body mass index [BMI] > 30 kg/m2) and 13 female controls (BMI < 26 kg/m2) without a history of recent or active infection. Glucose and insulin levels were measured at 0, 1, and 2 hours after a 75-g oral glucose load. There was no significant difference in plasma TNFalpha or IL-6 levels between obese and non-obese subjects overall (2.10 +/- 0.19 v 1.65 +/- 0.18 pg/mL and 2.06 +/- 0.29 v 1.50 +/- 0.17 pg/mL, respectively). However, TNFalpha levels were significantly elevated in obese subjects with a 2-hour glucose level more than 140 mg/dL (n = 8) compared with the other obese subjects (n = 18) and the non-obese controls (2.88 +/- 0.46 v 1.75 +/- 0.10 and 1.65 +/- 0.18 pg/mL, respectively, P < .01). Furthermore, the TNFalpha level correlated significantly with the waist to hip ratio ([WHR] r = .53, P < .01) and fasting and post-oral glucose tolerance test (OGTT) insulin levels (r = .47, P < .02), but not with the BMI, and was higher in obese women with a WHR more than 0.90 (n = 14) in comparison to those with a WHR less than 0.90 (n = 12, 2.47 +/- 0.29 v 1.66 +/- 0.18 pg/mL, respectively, P < .03). The corresponding plasma leptin level was significantly higher in obese women versus the control group (41.6 +/- 2.5 v22.3 +/- 2.9 ng/mL, P < .001) and was related to the BMI (r = .60, P < .01) but not to TNFalpha or the WHR. There were no significant differences in the corresponding IL-6 concentration between groups, and IL-6 did not correlate with TNFalpha, leptin, BMI, WHR, or insulin levels. In conclusion, circulating TNFalpha levels are higher in abdominal obesity compared with peripheral obesity, and may contribute to the insulin resistance that more commonly complicates the former pattern of fat distribution.


Assuntos
Tecido Adiposo/anatomia & histologia , Interleucina-6/sangue , Obesidade/sangue , Obesidade/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo , Abdome , Adulto , Glicemia/metabolismo , Constituição Corporal , Índice de Massa Corporal , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Insulina/sangue , Pessoa de Meia-Idade , Análise de Regressão , Fator de Necrose Tumoral alfa/análise
20.
J Clin Endocrinol Metab ; 84(9): 3010-2, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10487656

RESUMO

Nontraumatic avascular necrosis (AVN) of the hip is commonly caused by exogenous glucocorticoid administration, whereas it has rarely been associated with endogenous hypercortisolism. We report a 30-yr-old woman with Cushing's disease whose presenting manifestation was early AVN of the hip. Although plain x-ray was negative, magnetic resonance imaging (MRI) of the hip showed stage 2 AVN. Her orthopedic disease was considered an emergency, and thus, it was treated with core decompression before the diagnosis of Cushing's syndrome (CS) was pursued further. The femur recovered fully, as demonstrated by her improved clinical picture and a subsequent MRI. AVN carries a poor prognosis, if not treated early. The diagnostic procedure of choice is MRI, because plain radiographs are falsely negative in early stages. This case illustrates that AVN can be the presenting manifestation of CS; to prevent irreversible effects on the femoral head, core decompression should not be delayed for the purpose of evaluation and treatment of CS.


Assuntos
Síndrome de Cushing/diagnóstico , Necrose da Cabeça do Fêmur/diagnóstico , Necrose da Cabeça do Fêmur/cirurgia , Adulto , Síndrome de Cushing/complicações , Descompressão Cirúrgica , Tratamento de Emergência , Feminino , Necrose da Cabeça do Fêmur/etiologia , Humanos , Imageamento por Ressonância Magnética
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