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This Position Statement updates the different components of the therapy of obesity (lifestyle intervention, drugs, and surgery) in children and adolescents, previously reported in the consensus position statement on pediatric obesity of the Italian Society of Pediatric Endocrinology and Diabetology and the Italian Society of Pediatrics. Lifestyle intervention is the first step of treatment. In children older than 12 years, pharmacotherapy is the second step, and bariatric surgery is the third one, in selected cases. Novelties are available in the field of the medical treatment of obesity. In particular, new drugs demonstrated their efficacy and safety and have been approved in adolescents. Moreover, several randomized control trials with other drugs are in process and it is likely that some of them will become available in the future. The increase of the portfolio of treatment options for obesity in children and adolescents is promising for a more effective treatment of this disorder.
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Obesidade Infantil , Pediatria , Criança , Humanos , Adolescente , Obesidade Infantil/cirurgia , Consenso , Sociedades Médicas , ItáliaRESUMO
Childhood obesity is a global public health problem. Worldwide, 41 million children under 5 years and 340 million children and adolescents between 5 and 19 years are overweight. In addition, the recent COVID-19 epidemic has further amplified this social phenomenon. Obesity is a condition associated with various comorbidities, such as nonalcoholic fatty liver disease (NAFLD). The pathophysiology of NAFLD in obesity is intricate and involves the interaction and dysregulation of several mechanisms, such as insulin resistance, cytokine signaling, and alteration of the gut microbiota. NAFLD is defined as the presence of hepatic steatosis in more than 5% of hepatocytes, evaluated by histological analysis. It can evolve from hepatic steatosis to steatohepatitis, fibrosis, cirrhosis, hepatocellular carcinoma, and end-stage liver failure. Body weight reduction through lifestyle modification remains the first-line intervention for the management of pediatric NAFLD. Indeed, studies suggest that diets low in fat and sugar and conversely rich in dietary fibers promote the improvement of metabolic parameters. This review aims to evaluate the existing relationship between obesity and NAFLD in the pediatric population and to assess the dietary patterns and nutritional supplementations that can be recommended to prevent and manage obesity and its comorbidities.
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COVID-19 , Doença Hepática Terminal , Hepatopatia Gordurosa não Alcoólica , Obesidade Infantil , Adolescente , Criança , Humanos , Pré-Escolar , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sobrepeso/metabolismo , Obesidade Infantil/metabolismo , COVID-19/metabolismo , Dieta , Fibrose , Doença Hepática Terminal/patologia , Fígado/metabolismoRESUMO
Obesity has reached epidemic proportions, and the World Health Organization defined childhood overweight and obesity as a noncommunicable disease that represents the most serious public health challenges of the twenty-first century. Oxidative stress, defined as an imbalance between oxidants and antioxidants causing an impairment of the redox signals, is linked to the development of metabolic diseases. In addition, reactive oxygen species generated during metabolic disorder could increase inflammation, causing the development of insulin resistance, diabetes, and cardiovascular disease. We analyze serum levels of cysteine (Cys), cysteinyl-glycine (Cys-Gly), homocysteine (Hcy), and glutathione (GSH), and other markers of oxidative stress, such as thiobarbituric acid reactive substances (T-BARS), 8-isoprostane, and protein carbonyl in our children with obesity. Total antioxidant status was also determined. We found lower GSH and Cys-Gly levels, and higher Hcy and oxidative stress markers levels. We also found a positive correlation between Body Mass Index (BMI), Cys, GSH, and Hcy levels, between insulin and Cys levels, and between BMI and the homeostasis model assessment-estimated insulin resistance (HOMA-IR) with 8-isoprostane levels. Finally, we found a correlation between age and GSH and Cys levels. The deficiency of GSH could be restored by dietary supplementation with GSH precursors, supplying an inexpensive approach to oppose oxidative stress, thus avoiding obesity complications.
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Resistência à Insulina , Estresse Oxidativo , Obesidade Infantil , Compostos de Sulfidrila , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Criança , Cisteína/metabolismo , Glutationa/metabolismo , Humanos , Obesidade Infantil/metabolismo , Compostos de Sulfidrila/metabolismoRESUMO
PURPOSE OF REVIEW: Prader-Willi syndrome (PWS) is a rare and complex genetic disorder with multiple effects on the metabolic, endocrine, and neurological systems, as well as behavioral and intellectual difficulties. Despite advances in understanding the genetic basis of obesity in PWS, there are conflicting data on its management. Therefore, the present manuscript aims to provide an update on the nutritional treatment and pharmacological approach in adult patients with PWS. RECENT FINDINGS: The management of obesity in patients with PWS is challenging and requires the cooperation of an experienced multidisciplinary team, including the nutritionist. An adequate clinical evaluation including nutritional and biochemical parameters should be performed to tailor the best therapeutic strategy. Both lifestyle and pharmacological interventions may represent useful strategies to prevent the high rate of morbidity and mortality related to PWS. The use of bariatric surgery is still controversial. Although it is imperative to adopt an obesity prevention strategy in childhood, there is promising evidence for the treatment of obesity in adulthood with current obesity medications in conjunction with lifestyle interventions.
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Síndrome de Prader-Willi , Humanos , Adulto , Síndrome de Prader-Willi/terapiaRESUMO
The characteristics of scoliosis were investigated in a large cohort of children and adults with Prader-Willi syndrome (PWS), analysing the role of age, gender, puberty, body mass index (BMI), genotype and growth hormone therapy (GHT) on its onset and severity. A retrospective cross-sectional study was performed in 180 patients with genetically confirmed PWS (96 females), aged 17.6 ± 12 years. Eighty-five subjects (47%) were obese. One hundred and fifty subjects (83.3%) were on GHT, while 30 patients had never been treated. Overall, 150 subjects (83.3%) were affected by scoliosis, 80.2% of children and adolescents and 87.8% of adults. A mild degree of scoliosis was observed in 58 patients (38.7%), moderate in 43 (28.7%) and severe in 49 (32.6%). Median age at diagnosis of scoliosis was 6.3 years, while the severe forms were diagnosed earlier (median age: 3.8 years). The cumulative probability at 5 years of age was equal to 0.403 and almost doubled at 15 years. No significant associations were found between scoliosis and genotype, gender, pubertal stage, GHT and BMI. A corset was prescribed to 75 subjects (50%) at a median age of 7.5 years, while 26 subjects (17.3%) underwent surgery at a median age of 13.1 years. Our data indicate that scoliosis is one of the major concerns for PWS patients that increases with age, and therefore suggest the need for regular systematic monitoring of spinal deformity from paediatric age.
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Excess body weight has been considered beneficial to bone health because of its anabolic effect on bone formation; however, this results in a poor quality bone structure. In this context, we evaluated the involvement of circulating extracellular vesicles in the impairment of the bone phenotype associated with obesity. Circulating extracellular vesicles were collected from the plasma of participants with normal weight, as well as overweight and obese participants, quantified by flow cytometry analysis and used to treat mesenchymal stromal cells and osteoblasts to assess their effect on cell differentiation and activity. Children with obesity had the highest amount of circulating extracellular vesicles compared to controls. The treatment of mesenchymal stromal cells with extracellular vesicles from obese participants led to an adipogenic differentiation in comparison to vesicles from controls. Mature osteoblasts treated with extracellular vesicles from obese participants showed a reduction in differentiation markers in comparison to controls. Children with obesity who regularly performed physical exercise had a lower circulating extracellular vesicle amount in comparison to those with a sedentary lifestyle. This pilot study demonstrates how the high amount of circulating extracellular vesicles in children with obesity affects the bone phenotype and that physical activity can partially rescue this phenotype.
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Vesículas Extracelulares , Células-Tronco Mesenquimais , Obesidade Infantil , Humanos , Osteogênese , Projetos Piloto , Diferenciação Celular , Adipogenia , Osteoblastos , Células CultivadasRESUMO
Childhood, adolescent, and young adult cancer survivors are at increased risk of reduced bone mineral density. Clinical practice surveillance guidelines are important for timely diagnosis and treatment of these survivors, which could improve bone mineral density parameters and prevent fragility fractures. Discordances across current late effects guidelines necessitated international harmonisation of recommendations for bone mineral density surveillance. The International Late Effects of Childhood Cancer Guideline Harmonization Group therefore established a panel of 36 experts from ten countries, representing a range of relevant medical specialties. The evidence of risk factors for very low and low bone mineral density and fractures, surveillance modality, timing of bone mineral density surveillance, and treatment of very low and low bone mineral density were evaluated and critically appraised, and harmonised recommendations for childhood, adolescent, and young adult cancer survivors were formulated. We graded the recommendations based on the quality of evidence and balance between potential benefits and harms. Bone mineral density surveillance is recommended for survivors treated with cranial or craniospinal radiotherapy and is reasonable for survivors treated with total body irradiation. Due to insufficient evidence, no recommendation can be formulated for or against bone mineral density surveillance for survivors treated with corticosteroids. This surveillance decision should be made by the survivor and health-care provider together, after careful consideration of the potential harms and benefits and additional risk factors. We recommend to carry out bone mineral density surveillance using dual-energy x-ray absorptiometry at entry into long-term follow-up, and if normal (Z-score > -1), repeat when the survivor is aged 25 years. Between these measurements and thereafter, surveillance should be done as clinically indicated. These recommendations facilitate evidence-based care for childhood, adolescent, and young adult cancer survivors internationally.
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Densidade Óssea , Sobreviventes de Câncer/estatística & dados numéricos , Monitoramento Epidemiológico , Adolescente , Adulto , Doenças Ósseas Metabólicas/complicações , Criança , Humanos , Fatores de Risco , Adulto JovemRESUMO
Excess adiposity in childhood may affect bone development, ultimately leading to bone frailty. Previous reports showing an increased rate of extremity fractures in children with obesity support this fear. On the other hand, there is also evidence suggesting that bone mineral content is higher in obese children than in normal weight peers. Both adipocytes and osteoblasts derive from multipotent mesenchymal stem cells (MSCs) and obesity drives the differentiation of MSCs toward adipocytes at the expense of osteoblast differentiation. Furthermore, adipocytes in bone marrow microenvironment release a number of pro-inflammatory and immunomodulatory molecules that up-regulate formation and activation of osteoclasts, thus favoring bone frailty. On the other hand, body adiposity represents a mechanical load, which is beneficial for bone accrual. In this frame, bone quality, and structure result from the balance of inflammatory and mechanical stimuli. Diet, physical activity and the hormonal milieu at puberty play a pivotal role on this balance. In this review, we will address the question whether the bone of obese children and adolescents is unhealthy in comparison with normal-weight peers and discuss mechanisms underlying the differences in bone quality and structure. We anticipate that many biases and confounders affect the clinical studies conducted so far and preclude us from achieving robust conclusions. Sample-size, lack of adequate controls, heterogeneity of study designs are the major drawbacks of the existing reports. Due to the increased body size of children with obesity, dual energy absorptiometry might overestimate bone mineral density in these individuals. Magnetic resonance imaging, peripheral quantitative CT (pQCT) scanning and high-resolution pQCT are promising techniques for the accurate estimate of bone mineral content in obese children. Moreover, no longitudinal study on the risk of incident osteoporosis in early adulthood of children and adolescents with obesity is available. Finally, we will address emerging dietary issues (i.e., the likely benefits for the bone health of polyunsaturated fatty acids and polyphenols) since an healthy diet (i.e., the Mediterranean diet) with balanced intake of certain nutrients associated with physical activity remain the cornerstones for achieving an adequate bone accrual in young individuals regardless of their adiposity degree.
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Desenvolvimento Ósseo/fisiologia , Osso e Ossos/fisiologia , Obesidade Infantil , Adolescente , Densidade Óssea/fisiologia , Criança , Exercício Físico/fisiologia , Humanos , Osteoporose/etiologia , Osteoporose/metabolismo , Obesidade Infantil/complicações , Obesidade Infantil/metabolismo , Obesidade Infantil/fisiopatologia , Puberdade/fisiologiaRESUMO
Prader-Willi syndrome (PWS) is a complex multisystem disorder due to the absent expression of the paternally active genes in the PWS critical region on chromosome 15 (15q11.2-q13). The syndrome is considered the most common genetic cause of obesity, occurring in 1:10,000-1:30,000 live births. Its main characteristics include neonatal hypotonia, poor feeding, and lack of appetite in infancy, followed by weight gain, lack of satiety, and uncontrolled appetite, frequently after the age of 2-3 years. The clinical picture includes short stature, multiple endocrine abnormalities (hypogonadism, growth hormone/insulin-like growth factor-I axis dysfunction, hypothyroidism, central adrenal insufficiency), dysmorphic features, scoliosis, osteoporosis, mental retardation, and behavioral and psychiatric problems. Subjects with PWS will become severely obese unless their food intake is strictly controlled. Constant and obsessive food seeking behavior can make life very difficult for both the family and caretakers. Prevention of obesity is mandatory in these patients from the first years of life, because once obesity develops it is difficult to maintain the control of food intake. In fact, PWS subjects die prematurely from complications conventionally related to obesity, including diabetes mellitus, metabolic syndrome, sleep apnea, respiratory insufficiency, and cardiovascular disease. The mechanisms underlying hyperphagia in PWS are not completely known, and to date no drugs have proven their efficacy in controlling appetite. Consequently, dietary restriction, physical activity, and behavior management are fundamental in the prevention and management of obesity in PWS. In spite of all available therapeutic tools, however, successful weight loss and maintenance are hardly accomplished. In this context, clinical trials with new drugs have been initiated in order to find new possibilities of a therapy for obesity in these patients. The preliminary results of these studies seem to be encouraging. On the other hand, until well-proven medical treatments are available, bariatric surgery can be taken into consideration, especially in PWS patients with life-threatening comorbidities.
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BACKGROUND: Thyroid gland disorders are variably associated with Prader-Willi syndrome (PWS). Many of the clinical features in newborns with PWS are similar to those found in congenital hypothyroidism (CH). CASE PRESENTATION: We report a case of a girl with CH and PWS. At the age of 9 months CH caused by an ectopic sublingual thyroid was diagnosed, and hormone replacement therapy was started. In spite of this treatment a decrease in growth velocity, weight excess and delayed development were observed. At the age of 9 years PWS was suspected on the basis of phenotype and genetic tests confirmed a maternal uniparental disomy of chromosome 15. This is the second reported case of hypothyroidism due to an ectopic sublingual thyroid gland in PWS suggesting that, although rare, an association between CH and PWS may exist. In our case diagnosis of PWS was delayed because mental retardation, hypotonia, obesity and short stature were initially attributed to hypothyroidism. CONCLUSIONS: In this context PWS should be considered in obese children with CH who do not improve adequately with l-thyroxine therapy. Also, thyroid function in all PWS children should be assessed regularly in order to avoid delayed diagnosis of hypothyroidism.
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Coristoma , Hipotireoidismo Congênito/etiologia , Diagnóstico Tardio , Síndrome de Prader-Willi/diagnóstico por imagem , Doenças da Língua/diagnóstico , Adulto , Hipotireoidismo Congênito/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Síndrome de Prader-Willi/fisiopatologia , Cintilografia/métodos , Doenças Raras , Glândula TireoideRESUMO
UNLABELLED: The aim of this study was to analyse the relationship between insulin-glucose metabolism, nocturnal blood pressure dipping and nonalcoholic fatty liver disease (NAFLD) in obese adolescents without diabetes. One hundred one consecutive children, with biopsy-proven NAFLD, were included in this study. Blood samples were drawn for the analyses of liver function tests, insulin-glucose metabolism and lipid profile appraisal. An ambulatory blood pressure measurement (ABPM) was performed. Seventy-six children (75.3 %) were systolic nondippers, and 23 of them were diastolic nondippers (30.3 %). No differences were found in the anthropometric parameters between the two groups. When compared to the systolic dippers, the systolic nondippers had higher medians of mean nocturnal blood pressure, glucose at 0, 60 and 120 min in the oral glucose tolerance test (OGTT), OGTT insulin at all time points and insulin-resistance values. No correlation of histopathological features with dipping/nondipping statuses was found. CONCLUSIONS: We found an association between a nocturnal blood pressure fall and measures of insulin levels, independent of obesity, or daytime blood pressure levels, among the obese patients with NAFLD. Although no association between nondipping profiles and NAFLD was observed in our study, further studies with a longer term follow-up are needed, to better elucidate the complex link between these particular entities.
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Pressão Sanguínea/fisiologia , Resistência à Insulina/fisiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Obesidade Infantil/fisiopatologia , Adolescente , Antropometria , Glicemia , Determinação da Pressão Arterial , Monitorização Ambulatorial da Pressão Arterial , Criança , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Estudos ProspectivosAssuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Adolescente , Antipsicóticos/efeitos adversos , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Resistência à Insulina , Masculino , Metformina/efeitos adversos , Metformina/farmacocinética , Hepatopatia Gordurosa não Alcoólica , Obesidade/tratamento farmacológico , Síndrome do Ovário Policístico/tratamento farmacológico , Puberdade Precoce/tratamento farmacológicoRESUMO
UNLABELLED: A long pre-diabetic phase of abnormal glucose tolerance is described in subjects with cystic fibrosis (CF) since childhood. OBJECTIVE: The aims of the study were to compare oral glucose tolerance test (OGTT) and continuous glucose monitoring system (CGMS) in the diagnosis of altered glucose metabolism, and to longitudinally evaluate the role of CGMS in predicting glucose metabolism deterioration in children with CF. METHODS: Seventeen children with CF and 14 controls were enrolled (mean age 13.3+/-3.0 years). All subjects underwent OGTT and CGMS registration. On the basis of OGTT, children were classified as normal glucose tolerance, impaired glucose tolerance (IGT), IGT plus at least one glucose value above 200 mg/dl at intermediate OGTT points (IGT+200) and CF-related diabetes (CFRD). HbA1c, glucose area under the curve, insulin sensitivity, and insulinogenic and disposition indexes were also considered. Subjects with CF underwent another OGTT after 2.5 years. RESULTS: Baseline OGTT revealed 3/17 (7.6%) children with CF with at least one glucose value above 200 mg/dl (1 CFRD and 2 IGT+200), while CGMS revealed 6/17 (35.3%) children with glucose excursions above 200 mg/dl (P=0.010). None of the controls showed glucose over 200 mg/dl either at OGTT or at CGMS. At the 2.5-year follow-up OGTT, all the six subjects who had diabetic glucose excursion (i.e. >200 mg/dl) at baseline CGMS presented IGT+200 or CFRD. In logistic regression analysis, CGMS diabetic excursion was the strongest predictor of IGT+200 and CFRD (P<0.001). CONCLUSIONS: CGMS could be a useful tool to predict glucose metabolism derangements in children affected by CF.
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Automonitorização da Glicemia/métodos , Glicemia/metabolismo , Fibrose Cística/sangue , Intolerância à Glucose/sangue , Adolescente , Área Sob a Curva , Criança , Feminino , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Modelos Logísticos , Estudos Longitudinais , Masculino , Valor Preditivo dos TestesAssuntos
Síndrome de ACTH Ectópico/diagnóstico por imagem , Neoplasias Brônquicas/diagnóstico por imagem , Tumor Carcinoide/diagnóstico por imagem , Síndrome de Cushing/diagnóstico por imagem , Síndrome de ACTH Ectópico/etiologia , Adulto , Neoplasias Brônquicas/etiologia , Tumor Carcinoide/etiologia , Síndrome de Cushing/etiologia , Diagnóstico Diferencial , Humanos , Radioisótopos de Índio , Masculino , Octreotida/análogos & derivados , Ácido Pentético/análogos & derivados , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: To report a case of ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) in a patient with two distinct neuroendocrine tumors and to highlight the difficulties of establishing the differential diagnosis of EAS. METHODS: We describe the clinical presentation of the current case, discuss its management, and report the results of molecular studies undertaken to determine whether the two tumors had a common origin. RESULTS: A 52-year-old woman presented with obvious features of Cushing's syndrome. Findings on hormonal evaluation were consistent with EAS. Pituitary magnetic resonance imaging revealed normal findings. Computed tomographic imaging disclosed two masses, one in the lung and one in the pancreas. Somatostatin receptor scintigraphy showed uptake only in the pancreatic mass, which was surgically removed. It was a well-differentiated neuroendocrine tumor, with negative immunostaining for ACTH. Hypercortisolemia did not resolve after removal of the pancreatic tumor. The lung mass was subsequently excised, and pathology examination showed a carcinoid tumor with immunostaining for ACTH. Thereafter, plasma ACTH became immeasurable. The two tumors had similar patterns of X-chromosome inactivation; thus, whether they arose independently could be neither confirmed nor excluded. CONCLUSION: This case demonstrates that, in the presence of more than one neuroendocrine tumor, somatostatin receptor scintigraphy may misguide the decision regarding the appropriate surgical course in patients with EAS, and it highlights the need for accurate studies to determine the source of ACTH in patients with EAS.
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Hormônio Adrenocorticotrópico/metabolismo , Síndrome de Cushing/etiologia , Neoplasias Pulmonares/metabolismo , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/metabolismo , Síndrome de ACTH Ectópico/diagnóstico , Hormônio Adrenocorticotrópico/sangue , Síndrome de Cushing/diagnóstico , Análise Mutacional de DNA , Diagnóstico Diferencial , Feminino , Hormônios Ectópicos/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Receptores de Somatostatina/análise , Somatostatina/metabolismo , Inativação do Cromossomo XRESUMO
In women who are growth hormone (GH) deficient, exogenous estrogens increase the dosage of GH that is needed to normalize circulating levels of insulin-like growth factor (IGF-1). Serum IGF-1 derives mostly from the liver, and it is unknown whether the peripheral effects of GH are also impaired by estrogens. Because the ultimate effect of GH is longitudinal growth, we have investigated the influence of estrogen administration on the growth response to recombinant mouse GH therapy in prepubertal GH-deficient (GHD) GHRH knockout (GHRHKO) female mice. Twenty-four GHRHKO female mice (4 animals/group) were treated for 4 weeks (from the second to sixth week of age) with the following schedules: Group I, GH only (25 microg/day); Group II, subcutaneous (sc) ethynil estradiol (EE) (0.035 ES01247g/day); Group III, GH + scEE; Group IV, oral (po) EE (0.035 microg/day); Group V, GH + poEE; Group VI, placebo. At the end of the treatment period, we measured uterine weight, total body weight (TBW), body length (nose-anus, N-A), and femur length. In addition, serum IGF-1 levels were measured. Uteri of mice treated with oral or scEE showed similar increases in weight. There was no difference in the increase in longitudinal growth parameters between mice treated with GH alone or with GH in association with oral or scEE. Serum IGF-1 decreased in animals treated with GH + scEE, compared with GH group, but no group was significantly different from placebo. These results show that subcutaneous or oral EE does not reduce the growth response to GH in female GHD mice.
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Tamanho Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Estrogênios/farmacologia , Etinilestradiol/administração & dosagem , Hormônio do Crescimento/fisiologia , Animais , Etinilestradiol/farmacologia , Feminino , Hormônio do Crescimento/genética , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Knockout , Radioimunoensaio , Proteínas Recombinantes , Fatores de TempoRESUMO
Growth hormone (GH) secretagogues (GHS) stimulate GH secretion in vivo in humans and in animals. They act on the ghrelin receptor, expressed in both the hypothalamus and the pituitary. It is unknown whether GHSs act predominantly by increasing the release of hypothalamic GH-releasing hormone (GHRH) or by acting directly on the somatotroph cells. We studied whether a potent GHS could stimulate growth in the absence of endogenous GHRH. To this end, we used GHRH knockout (GHRH-KO) mice. These animals have proportionate dwarfism due to severe GH deficiency (GHD) and pituitary hypoplasia due to reduced somatotroph cell mass. We treated male GHRH-KO mice for 6 wk (from week 1 to week 7 of age) with GH-releasing peptide-2 (GHRP-2, 10 microg s.c. twice a day). Chronic treatment with GHRP-2 failed to stimulate somatotroph cell proliferation and GH secretion and to promote longitudinal growth. GHRP-2-treated mice showed an increase in total body weight compared with placebo-treated animals, due to worsening of the body composition alterations typical of GHD animals. These data demonstrate that GHRP-2 failed to reverse the severe GHD caused by lack of GHRH.
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Hormônio Liberador de Gonadotropina/deficiência , Oligopeptídeos/farmacologia , Animais , Northern Blotting , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio do Crescimento/sangue , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Imuno-Histoquímica , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tamanho do Órgão/efeitos dos fármacos , Hipófise/metabolismo , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: The aim of the study was to identify the factors that are predictive of recurrence after thyroid lobectomy for unilateral non-toxic thyroid goiter in an endemic region through a multivariate analysis. METHODS: Two hundred sixty-eight consecutive patients who underwent thyroid lobectomy and who were evaluated by the same endocrinologist were included. Univariate and multivariate analysis analyzed the relationship between sex, age, preoperative thyroid-stimulating hormone, duration of disease, duration of levothyroxine (LT4) preoperative therapy, cytologic results, histologic results, resected thyroid weight, numbers and diameters of thyroid nodules, morphologic alterations of the remnant lobe, follow-up length, postoperative LT4 therapy, ultrasonographic evidence of recurrence, and reoperation. RESULTS: The incidence of recurrence was 33.9% (91/268 patients) after a mean follow-up time of 79.9 months (range, 12-251 months), female sex ( P = .016), multiple nodules ( P = .017), and lack of postoperative LT4 therapy ( P = .0009) were predictive factors of recurrence. Reoperation was performed in 20 patients (7.4%); factors that were predictive of reoperation were the presence of multiple nodules ( P = .008), resected thyroid weight ( P = .00006), and lack of postoperative hormonal therapy ( P = .0005). CONCLUSIONS: Thyroid lobectomy for unilateral non-toxic goiter, when combined with suppressive or substitutive thyroxin therapy, resulted in a low rate of recurrence and reoperation in an endemic area.