Expression of E-cadherin, Slug and NCAM and its relationship to tumor invasiveness in patients with acromegaly

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.

Physical activities in daily life and functional capacity compared to disease activity control in acromegalic patients: impact in self-reported quality of life / Avaliação da atividade física na prática de vida diária comparada com o nível de atividade da doença em pacientes acromegálicos: impacto na percepção da qualidade de vida

OBJECTIVE: To evaluate the quality of life and its association with daily physical activity and disease control in acromegalic patients. SUBJECTS AND METHODS: A cross-sectional, case series study, composed of 42 patients recruited from the Neuroendocrinology Unit of the University Hospital of Brasilia. Level of physical activity was accessed by the International Physical Activity Questionnaire (IPAQ 6-short-form), which evaluates the weekly time spent on physical activity of moderate to vigorous intensity in different contexts of life. Quality of life was evaluated by The Medical Outcome Study Questionnaire Short Form (SF-36). Data was compared to growth hormone (GH) and insulin-like growth factor (IGF-1) levels. Students' t test and Fisher test were used, p < 0.05, SPSS 17.0. RESULTS: Twenty-two women, aged 51.33 ± 14.33 and 20 men, aged 46.2 ± 13.18 were evaluated. Arthralgia was present in 83% of cases. In men, the most common sites of pain were the knees (73%), spine (47% lumbar, and 53% thoracic and cervical segments), hands and wrists (40%). Higher scores on SF-36 were observed in patients with intermediate or high levels of physical activity, in the domains social functioning (75 CI 57.3-92.6), general health (75.5 CI 60.4-90.5), mental health (70 CI 57.8-82.1). CONCLUSIONS: In this study, the presence and severity of physical disability and pain were not associated with initial GH and IGF-1 levels or time of exposure to GH excess. However, the patients considered controlled, with normal a normal age-adjusted IGF-1, presented higher scores in SF-36, in physical and emotional domains, compared with patients with persistent hypersomatotrophism. These findings suggest benefits of metabolic control in self-reported quality of life.

OBJETIVO: Avaliar a qualidade de vida e sua associação com a prática de vida diária e controle metabólico em pacientes portadores de acromegalia. SUJEITOS E MÉTODOS: Estudo seccional de série de casos, composto por 42 pacientes recrutados na Unidade de Neuroendocrinologia do Hospital Universitário de Brasília. O nível de atividade física foi estimado pelo Questionário Internacional de Atividade Física (IPAQ-6), que avalia o tempo gasto semanalmente em atividades físicas que variam de intensidade em diferentes contextos de vida. A qualidade de vida foi avaliada pelo questionário SF-36. Os dados obtidos foram comparados aos níveis de hormônio do crescimento (GH) e fator de crescimento semelhante à insulina (IGF-1). Os testes t Students e Fisher foram aplicados e p < 0,05 foram considerados significativos, SPSS 17.0. RESULTADOS: Avaliaram-se 22 mulheres com idades de 51,33 ± 14,33 e 20 homens com idades de 46,2 ±13,18. Artralgia foi relatada em 83% dos pacientes. Em homens, os sítios de dor mais comuns foram os joelhos (73%), coluna vertebral (47% lombar, 53% segmentos torácico e cervical), mãos e quadris (40%). Os maiores escores no SF-36 foram observados em pacientes com níveis intermediário ou alto de atividade física, sobretudo nos domínios social (75 CI 57,3-92,6), saúde geral (75,5 CI 60,4-90,5), saúde mental (70 CI 57,8-82,1). CONCLUSÕES: A presença e a severidade do prejuízo no desempenho físico e dor não se associaram com Gh e IGF-1 no diagnóstico, tempo de exposição prévio à doença. Todavia, pacientes considerados controlados apresentaram melhores escores nos domínios físico e emocional, comparados com pacientes com hipersomatotrofismo persistente. Tais achados sugerem benefícios do controle metabólico na qualidade de vida.

Prostatic disorders in acromegalic patients experience of a Brazilian center

Introduction Published data suggest that patients with acromegaly have an increased prevalence of prostate disorders. Objective To evaluate prostatic disorders in acromegalic patients comparing these results after one year of treatment of acromegaly and with a group of healthy men. Materials and Methods This study was composed of two parts: sectional study comparing patients with healthy controls (baseline) and prospective, longitudinal study (at baseline and after one year of treatment). Forty acromegalic patients were enrolled and evaluated at baseline and after one year with the application of international prostatic symptoms score (IPSS), digital rectal examination, measurements of growth hormone (GH), insulin-like growth factor-I (IGF-I), insulin-like growth factor-binding protein-3 (IGFBP-3), sex hormone-binding globulin (SHBG), prolactin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone, total and free prostate-specific antigen (PSA) levels and prostate ultrasonography (US). Thirty healthy men were selected as control group. Results We stratified patients and controls according to age, considering 40 years-old as cut off. Healthy controls under 40 had IPSS values lower than acromegalic patients. When considering only older patients and controls prostate hyperplasia and structural abnormalities were more frequent in acromegalics. After one year of treatment there was significant decrease in GH, IGF-I and prostate volume in acromegalics over 40 years-old. Conclusions Acromegalics under 40 have more urinary symptoms according to IPSS and above 40 years-old higher frequency of structural changes and increased prostate volume than healthy men. Significant reduction of GH and IGF-I levels during treatment of acromegaly leads to decrease in the prostate volume. .

Resistance to octreotide LAR in acromegalic patients with high SSTR2 expression: analysis of AIP expression / Resistência ao octreotide LAR em pacientes acromegálicos com alta expressão do SSTR2: avaliação da expressão do AIP

We present here the clinical and molecular data of two patients with acromegaly treated with octreotide LAR after non-curative surgery, and who presented different responses to therapy. Somatostatin receptor type 2 and 5 (SSTR2 and SSTR5), and aryl hydrocarbon receptor-interacting protein (AIP) expression levels were analyzed by qPCR. In both cases, high SSTR2 and low SSTR5 expression levels were detected; however, only one of the patients achieved disease control after octreotide LAR therapy. When we analyzed AIP expression levels of both cases, the patient whose disease was controlled after therapy exhibited AIP expression levels that were two times higher than the patient whose disease was still active. These two cases illustrate that, although the currently available somatostatin analogs bind preferentially to SSTR2, some patients are not responsive to therapy despite high expression of this receptor. This difference could be explained by differences in post-receptor signaling pathways, including the recently described involvement of AIP. Arq Bras Endocrinol Metab. 2012;56(8):501-6.

Apresentamos os dados clínicos e moleculares de dois pacientes com acromegalia tratados com octreotide LAR após cirurgia não curativa, com diferentes respostas a essa terapia medicamentosa. As expressões do receptor de somatostatina tipo 2 e 5 (SSTR2 e SSTR5) e da proteína de interação com o receptor aril hidrocarbono (AIP) foram analisadas por qPCR. Em ambos os casos, foi encontrada uma expressão elevada de SSTR2 e baixa do SSTR5. No entanto, o controle da doença foi obtido após tratamento com octreotide LAR em apenas um dos pacientes. Quando analisamos a expressão do AIP em ambos os casos, o paciente cuja doença foi controlada após a terapia medicamentosa apresentou uma expressão duas vezes maior do que a do paciente não controlado com o tratamento. Conclui-se que esses dois casos ilustram que, embora os análogos de somatostatina atualmente disponíveis se liguem preferencialmente ao SSTR2, alguns pacientes não respondem ao tratamento, apesar de uma elevada expressão desse receptor. Isso poderia ser explicado por alterações nas vias de sinalização pós-receptor, incluindo o envolvimento recentemente descrito da AIP. Arq Bras Endocrinol Metab. 2012;56(8):501-6.

Hypertension-related factors in patients with active and inactive acromegaly / Fatores implicados com a hipertensão em pacientes com acromegalia ativa e inativa

INTRODUCTION: There are several complications of the cardiovascular system caused by acromegaly, especially hypertension. OBJECTIVES: To evaluate hypertension characteristics in patients with cured/controlled acromegaly and with the active disease. PATIENTS AND METHODS: Cross-sectional study of the follow-up of forty-four patients with acromegaly submitted to clinical evaluation, laboratory tests and cardiac ultrasound. Patients with cured and controlled disease were evaluated as one group, and individuals with active disease as second one. RESULTS: Forty-seven percent of the patients had active acromegaly, and these patients were younger and had lower blood pressure levels than subjects with controlled/cured disease. Hypertension was detected in 50 percent of patients. Subjects with active disease showed a positive correlation between IGF-1 and systolic and diastolic blood pressure levels (r = 0.48, p = 0.03; and r = 0.42, p = 0.07, respectively), and a positive correlation between IGF-1 and urinary albumin excretion (UAE) rates. In patients with active disease, IGF-1 was a predictor of systolic blood pressure, although it was not independent of UAE rate. For individuals with cured/controlled disease, waist circumference and triglycerides were the predictors associated with systolic and diastolic blood pressure. CONCLUSIONS: Our findings suggest that blood pressure levels in patients with active acromegaly are very similar, and depend on excess GH. However, once the disease becomes controlled and IGF-1 levels decrease, their blood pressure levels will depend on the other cardiovascular risk factors.

INTRODUÇÃO: Existem várias complicações no sistema cardiovascular causadas pela acromegalia, especialmente a hipertensão. OBJETIVOS: Avaliar as características da hipertensão em pacientes com acromegalia curada/controlada e com doença ativa. PACIENTES E MÉTODOS: Estudo transversal com 44 pacientes com acromegalia seguidos em nosso serviço. Eles foram submetidos a avaliação clínica, exames laboratoriais e ecocardiograma. Pacientes com doença curada/controlada foram avaliados como um grupo único e os indivíduos com doença ativa como outro grupo. RESULTADOS: Quarenta e sete por cento dos pacientes apresentaram acromegalia ativa. Esses indivíduos foram mais jovens e apresentaram níveis mais baixos de pressão arterial que os indivíduos com doença controlada/curada. A hipertensão foi detectada em 50 por cento da amostra. Indivíduos com doença ativa mostraram uma correlação positiva entre os níveis de IGF-1 e os níveis de pressão arterial sistólica e de pressão arterial diastólica (r = 0,48, p = 0,03; e r = 0,42, p = 0,07, respectivamente) e também apresentaram uma correlação positiva entre IGF-1 e excreção urinária de albumina (EUA). Em pacientes com doença ativa, o IGF-1 foi um preditor da pressão arterial sistólica, embora não tenha sido independente da taxa de EUA. Para indivíduos com doença curada/controlada, a circunferência da cintura e os triglicérides foram os preditores associados aos níveis de pressão arterial sistólica e diastólica. CONCLUSÕES: Nossos resultados sugerem que os níveis pressóricos em pacientes com acromegalia ativa dependem do excesso de GH. No entanto, uma vez que a doença torna-se controlada e os níveis de IGF-1 reduzem, os níveis de pressão arterial dependerão de outros fatores de risco cardiovasculares.

Distúrbios cardiovasculares na acromegalia: [revisão] / Cardiovascular disturbances in acromegaly: [review]

A acromegalia acarreta uma série de distúrbios ao sistema cardiovascular, decorrentes da exposição crônica a níveis elevados de GH e IGF-1. Estes distúrbios são os principais responsáveis pelo aumento da mortalidade de acromegálicos. Entre as várias formas de acometimento cardiovascular, destaca-se a miocardiopatia acromegálica, entidade caracterizada, inicialmente, pelo estado hiperdinâmico, seguido de hipertrofia ventricular esquerda concêntrica e disfunção diastólica por déficit de relaxamento, culminando com disfunção sistólica e, por vezes, insuficiência cardíaca franca. Além disso, são também relevantes as arritmias, as valvulopatias, sobretudo mitral e aórtica, a cardiopatia isquêmica, a hipertensão e os distúrbios dos metabolismos glicêmico e lipídico. Nesta revisão são abordados os principais aspectos clínicos e prognósticos destas entidades, os efeitos do tratamento da acromegalia sobre elas e as repercussões correspondentes sobre a sobrevida dos pacientes.

Acromegaly causes a number of disorders in the cardiovascular system, resulting from chronic exposure to high levels of GH and IGF-1. Such disorders are the main responsible for increased mortality rates among acromegalic patients. Among several forms of cardiovascular impairment is acromegalic cardiomyopathy, an entity that is initially characterized by a hyperdynamic state, followed by concentric left ventricular hypertrophy and diastolic dysfunction due to relaxation deficit, culminating in systolic dysfunction and sometimes heart failure. In addition, arrhythmias and heart valve diseases are also relevant, especially mitral and aortic, ischemic heart disease, hypertension, and glucose and lipid metabolism disorders. This review approaches the main clinical and prognostic aspects of these entities, the effects of acromegaly treatment on them, and the respective consequences on patient survival.

Somatostatin receptors subtypes 2 and 5, dopamine receptor type 2 expression and gsp status as predictors of octreotide LAR® responsiveness in acromegaly / Expressão dos receptores da somatostatina subtipos 2 e 5 e do receptor da dopamina tipo 2 e gsp status como preditores de resposta ao octreotide LAR® na acromegalia

We present two acromegalic patients in which clinical and molecular data are discussed in regard to their ability to predict long term octreotide LAR® therapy response. Case reports: Patient 1: female, 36 years old at diagnosis. Basal GH and IGF-I at diagnosis were 133 ng/mL and 181 percent above the upper limit of reference values (ULRV), respectively. Growth hormone during acute test with subcutaneous octreotide decreased from 133 to 13 ng/mL. Patient started on primary octreotide LAR® therapy (20mg q28 days) and achieved biochemical parameters of disease control after 6 months. Molecular analysis of tumor fragments: gsp +; quantitative analysis of SSTR (somatostatin receptor) and DR (dopamine receptor) mRNA - SSTR2 23954; SSTR5 2407; DR2 total 17016 copies. Patient 2: male, 38 years old at diagnosis. Basal GH and IGF-I at diagnosis were 120 ng/mL and 114 percent ULRV, respectively. Patient underwent non-curative trans-sphenoidal surgery. Post-operative GH and IGF-I were 112 ng/mL and 137 percent ULRV, respectively. Growth hormone during acute test with subcutaneous octreotide decreased from 112 to 7 ng/mL. Octreotide LAR® therapy (20 mg q28 days) was then initiated. After 6 months of treatment, patient did not attain biochemical control of disease and displayed increased tumor volume. Molecular analysis of tumor fragments: gsp not done; quantitative analysis of SSTR and DR mRNA - SSTR2 416; SSTR5 3767; DR2 total 3439 copies. In conclusion, these two cases illustrate how laboratory data can be conflicting as predictors of octreotide LAR® responsiveness and how molecular analysis of tumor fragments can help explain different behaviors in clinically similar patients.

Apresentamos dois pacientes acromegálicos nos quais dados clínicos e moleculares são discutidos quanto à sua capacidade de predizer a resposta a longo prazo ao tratamento com octreotide LAR®. Relato dos casos: Paciente 1: Feminina, 36 anos de idade ao diagnóstico. GH e IGF-I ao diagnóstico 133 ng/mL e 181 por cento acima do limite superior do valor de referência (LSVR), respectivamente. GH durante o teste agudo com octreotide subcutâneo diminuiu de 133 para 13 ng/mL. Foi iniciado tratamento primário com octreotide LAR® (20 mg q28 dias) e a paciente alcançou os parâmetros bioquímicos de controle de doença depois de seis meses. Análise molecular do tumor: gsp +; análise quantitativa do mRNA de SSTR (receptores de somatostatina) e DR (receptor de dopamina) - SSTR2 23.954; SSTR5 2.407; DR2 total 17.016 cópias. Paciente 2: Masculino, 38 anos de idade ao diagnóstico. GH e IGF-I ao diagnóstico 120 ng/mL e 114 por cento LSVR, respectivamente. Paciente foi submetido à cirurgia trans-esfenoidal não-curativa. GH e IGF-I pós-operatórios 112 ng/mL e 137 por cento LSVR, respectivamente. GH durante o teste agudo diminuiu de 112 para 7 ng/mL. Foi iniciado tratamento com octreotide LAR® (20 mg q28 dias). Após seis meses o paciente não alcançou controle bioquímico e apresentou aumento do volume tumoral. Análise molecular do tumor: gsp não estudado; análise quantitativa do mRNA de SSTR e DR - SSTR2 416; SSTR5 3.767; DR2 total 3.439 cópias. Em conclusão, estes dois casos ilustram como dados laboratoriais podem ser conflitantes enquanto preditores de resposta ao tratamento com octreotide LAR® e como a análise molecular de fragmentos do tumor pode ajudar a explicar comportamentos diferentes em pacientes clinicamente semelhantes.

Avaliação do metabolismo da glicose em pacientes acromegálicos antes e após tratamento com octreotide LAR / Evaluation of glucose metabolism in acromegalic patients before and after treatment with octreotide LAR

OBJETIVO: Avaliar o metabolismo da glicose em pacientes acromegálicos antes e após o tratamento com octreotide LAR. PACIENTES E MÉTODOS: Este foi um estudo longitudinal e prospectivo com 30 pacientes do ambulatório de pesquisa em acromegalia do Serviço de Endocrinologia do Hospital Universitário Clementino Fraga Filho da Universidade Federal do Rio de Janeiro (HUCFF/UFRJ). Eles foram submetidos à avaliação clínica e laboratorial com dosagens de hormônio do crescimento (GH), fator de crescimento semelhante à insulina tipo I (IGF-I), insulina, pró-insulina, peptídeo C, hemoglobina glicosilada (HbA1c), proteína de ligação do IGF tipo 1 (IGFBP-1) e a um teste oral de tolerância à glicose (TOTG), antes e após seis meses de tratamento com octreotide LAR. Foi aplicado o teste dos postos sinalizados de Wilcoxon e o critério de determinação de significância adotado foi o nível de 5 por cento. RESULTADOS: Encontraram-se 16 pacientes (54 por cento) com tolerância normal à glicose, sete (23 por cento) com intolerância à glicose e sete (23 por cento) com diabetes melito (DM). Doze pacientes completaram os seis meses de tratamento, sendo que houve piora da tolerância à glicose em três e piora do controle glicêmico dos dois pacientes diabéticos. Houve aumento da circunferência abdominal (p = 0,03) e queda do GH (p = 0,04), por cento IGF-I acima do limite superior do valor de referência ( por centoLSVR) (p = 0,001), insulina (p = 0,019), peptídeo C (p = 0,002) e do modelo de avaliação homeostática (HOMA-IR) (p = 0,039). CONCLUSÕES: Nesta série, o tratamento com octreotide LAR acarretou piora da tolerância à glicose em três pacientes não-diabéticos e piora do controle glicêmico em dois diabéticos, apesar da diminuição da resistência insulínica (RI).

AIM OF THE STUDY: To evaluate the glucose metabolism in acromegalic patients before and after treatment with octreotide LAR. PATIENTS AND METHODS: This was a prospective and longitudinal study involving 30 patients from the acromegaly research outpatient clinic of the Endocrinology unit of the HUCFF/UFRJ. They underwent clinical and laboratorial evaluations, with measurements of growth hormone (GH), insulin-like growth factor type I (IGF-I), insulin, proinsulin, C peptide, glycosylated hemoglobin (HbA1c), IGF binding protein type 1 (IGFBP-1) and glucose, during oral glucose tolerance test (OGTT), before and after six months of treatment with octreotide LAR. The Wilcoxon signed-rank test was used and values of 5 percent were considered statistically significant. RESULTS: We found 16 (54 percent) patients with normal glucose tolerance, 7 (23 percent) with impaired glucose tolerance and 7 (23 percent) diabetics. Twelve patients completed the six-month treatment, out of which three showed worsening of glucose tolerance and two (diabetics) had worse blood glucose control. Whereas there was an increase in waist circumference (p=0.03), there was a decrease in GH (p=0.04), with percentIGF-I above the upper limit of reference values ( percent ULRV) [p=0.001], insulin (p=0.019), C peptide levels (p=0.002) and homeostatic model assessment (HOMA-IR) [p=0.039]. CONCLUSIONS: In this series, treatment with octreotide LAR led to a worsening of glucose tolerance in three non-diabetic patients and worsened glycemic control in two diabetics, in spite of reducing insulin resistance.

Usefulness of insulin-like growth factor binding protein-3 levels to determine acromegaly activity and effectiveness of transsphenoidal pituitary surgery

Background. Several series reported in the literature concerning the results of the treatment of acromegaly have difficult to evaluated because the indicators are inaccurate Methods. We investigated the usefulness of insulin. Like growth factor binding protein-3 (IGFBP) levels to determine disease activity after surgical treatment of acromegaly in 13 patients with confirmed somatotroph adenoma. Results. Before surgery, all 13 non-treated patients had levated serum levels of IGFBP-3 as well as total and free IGF-I. In addition, there was no overlap with the normal controls (p < 0.001). IGFBP-3 levels correlated significantly (0.91, p < 0.001) with GH suppressibility by glucose after surgery. Conclusions. These data confirm that IGFBP-3 is a better indicator of acromegalic activity than either total or free IGF-i. There was a high correlation with GH suppressibility by glucose after surgery; both free and total IGF-I could be considered sensitive markers only for diagnosis of active acromegaly but not for efficacy of surgery

Níveis plasmáticos de somatomedina C como indicadores de atividade acromegálica em pacientes submetidos a tratamento / Somatomedin C plasmatic levels as indicators of acromegalic activity in patients submitted to treatment

Foram estudados 11 pacientes acromegálicos submetidos à adenomectomia transesfenoidal no Serviço de Neurocirurgia da UERJ. Os níveis plasmáticos de Somatomedina C (SmC) após o tratamento foram utilizados como indicadores de atividade acromegálica residual e as variaçoes nos níveis de hormônio do crescimento (GH) na fase pós-operatória foram consideradas como indicadores da eficácia do tratamento. A possibilidade de persistência de resíduos tumorais foi analisada com a realizaçao de tomografia computadorizada da sela turca. As médias dos valores de SmC e GH dos pacientes acromegálicos, após a cirurgia, foram comparadas com as médias desses hormônios de um grupo-controle com 9 indivíduos normais. Houve sensível melhora nas manifestaçoes clínicas. A média dos valores plasmáticos basais de GH variou de 109,23 ng/ml+ 37,17 na fase pré-operatória para 21,11 ng/ml + 4,14, diferença sem significância estatística; ambas foram significativamente maiores do que a média dos valores basais de GH do grupo-controle, 1,33 ng/ml + 0,42 (p< 0,00l). A média dos valores plasmáticos de somatomedina C nos pacientes acromegálicos, após o tratamento, foi de 244,09 ng/ml + 27,35, significativamente maior do que a média dos valores desses hormônios nos indivíduos do grupo-controle, 98,44 ng/ml + 8,39 (p< 0,00l).Três pacientes (27 por cento) apresentaram resíduos tumorais na tomografia computadorizada de controle. A dosagem de SmC mostrou-se extremamente confiável na avaliaçao pós-operatória dos pacientes acromegálicos.

Effect of glucose-dependent insulinotropic polypeptide (GIP) on insulin response to glucose in acromegalics

The pancreatic beta-cell response to stimulation with glucose and GIP, single and combined, was studied in acromegalics and in normal subjects. Acromegalics had higher IRI and GIP basal values with glucose levels and glucose disposal in the normal range. Further, acromegalics showed a greater IRI response to glucose, GIP and glucose combined with GIP. The results suggested that high growth hormone levels cause a greater activity of the entero-insular axis both in the basal state and after meal ingestion, as mimicked by GIP infusion. From these and previous observations, it can be assumed that growth hormone induces a facilitation of the IRI response to metabolite substrates and hormones

Determinaçäo indireta da testosterona livre através de diálise em equílibrio e sua aplicaçåo em adultos normais e com alteraçöes nos níveis da globulina transportadora dos esteróides sexuais / Indirect determination of free testosterone through equilibrium dialysis, its application in adults with normal and abnormal SHBG levels

A fraçåo livre de testosterona é biologicamente ativa, portnato, importante para avaliaçåo da atividade androogêica. Desenvolvemos uma metodologia para determinaçåo indireta da testosterona livre, baseada em diálise por equilíbrio em soro nåo diluído. Foram dosadas testosterona total e livre, além de SHGB em 54 adultos normais (41 homens e 13 mulheres). Amostras provenientes de 15 pacientes masculinos: 8 acromegálicos e 7 hipertireóideos também foram analisadas e serviram de modelo, respectivamente para as situçöes de diminuiçåo e aumento de SHGB. A reprodutividade do método foi conseguida com a purificaçåo periódica da testosterona triciada, uniformizaçåo do ensaio quanto a duraçåo e temperatura, além da nåo diluiçåo da amostra. Os coeficientes de variaçåo intra e interensaio foram, respectivamente, 0,4 a 22,2 e 4,34 a 43,7 por cento. A técnica, de fácil execuçåo e reprodutibilidade, apresenta sensibilidade para discrimar valores de adultos normais de ambos os sexos, além de evidenciar a distribuiçåo da testosterona em patologias que alteram SHBG

Biochemical markers of acromegalic activity

Tomando como base un score clínico comparamos la efectividad de tres marcadores bioquímicos de actividad de acromegalia: a) la respuesta de hormona de crecimiento a la inyección endovenosa de TRH, b) el grado de supresión de los niveles de hormona de crecimiento una hora después de una sobrecarga oral de glucosa, c) los niveles plasmáticos basales de IGF-I. en 21 pacientes se realizaron 39 observaciones que comprendían los cuatro parámetros. De acuerdo con su score clínico los pacientes se dividieron en tres grupos: grupo I = prequirúrgicos; grupo II = mejorados pero aún clínicamente activos, grupo III = clínicamente inactivos. Como la frecuencia de resultados anormales luego de la inyección de TRH aumentó en vez de disminuir cuando los pacientes mejoraban clínicamente, este test se excluyó del análisis estadístico. En los grupos I, II y III tanto la presencia de valores de IGF-I plasmático por en cima de lo normal como la falta de supresión adecuada de hormona de crecimiento luego de una sobrecarga de glucosa aparecieron con frecuencias muy semejantes: la misma en el grupo I (100 por ciento) en el grupo II (71.4 por ciento); y 27.3 por ciento vs. 18.2 por ciento en el grupo III (p > 0.05). La contribución de un test al poder de detección del otro fue igual para ambos: 3 observaciones sobre un total de 39(5.1 por ciento). Considerando que el nivel plasmático basal de IGF-I es estadísticamente tan útil como la supresión de hormona de crecimiento y teniendo en cuenta que el primero es mucho más simple para el paciente y el laboratorio, concluímos que el nivel plasmático basal de IGF-I es el mejor marcador bioquímico de actividad de acromegalia

Metabolic factors for urolithiasis in acromegalic patients

Acromegaly is associated with metabolic disturbances of calcium and phosphorus which can also contribute to renal lithogenesis. In order to characterize these disturbances more precisely, an oral calcium load test was performed on 14 active acromegalic patients. Serum and urinary levels of calcium, phosphorus, uric acid, creatinine and urinary cyclic AMP were determined. Of the 14 patients, 5 (36%) presented hypercalciuria, 5 (36%) presented intestinal calciumhyperabsorption and 6 (43%) had uric acid hyperexcretion. Two patients (14%) presented nephrolithiasis. The medical records of 32 additional acromegalic patients with or without active disease were reviewed for a history of previous stones, which was observed in three cases (9.5%). The present data suggest that nephrolithiasis occurs more frequently among acromegalic patients because of the underlying metabolic disturbances of calcium presented by this population

Endogenous hyperinsulinemia and release of growth hormone following a glucose load as well as in reponse to thyrotropin relasisng hormone in acromegaly

This study was designed to determine the relationship between endogenous hyperinsulinemia or free fatty acid (FFA) levels and the abnormal release of growth hormone (GH) during the oral glucose tolerance test (OGTT) or in response to thyrotropin releasing hormone (TRH) in acromegalic patients. Seventeen patients with acromegaly and nine healthy control subjects were studied. The 12 acromegalic patients who did not show the paradoxical response of increased GH secretion to the OGTT an/or to TRH exhibited higher insulin levels (total area under the curve during the OGTT) than patients who did. However, the FFA levels of the groups of acromegalic patients were similar. These data suggest that the endogenous hyperinsulinemia exhibited by many patients with acromegaly is associated with the absence of the paradoxical increase in GH secretion during the OGTT and/or after TRH