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1.
Int J Behav Med ; 26(5): 461-473, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30993601

RESUMEN

BACKGROUND: Stress can lead to excessive weight gain. Mindfulness-based stress reduction that incorporates mindful eating shows promise for reducing stress, overeating, and improving glucose control. No interventions have tested mindfulness training with a focus on healthy eating and weight gain during pregnancy, a period of common excessive weight gain. Here, we test the effectiveness of such an intervention, the Mindful Moms Training (MMT), on perceived stress, eating behaviors, and gestational weight gain in a high-risk sample of low income women with overweight/obesity. METHOD: We conducted a quasi-experimental study assigning 115 pregnant women to MMT for 8 weeks and comparing them to 105 sociodemographically and weight equivalent pregnant women receiving treatment as usual. Our main outcomes included weight gain (primary outcome), perceived stress, and depression. RESULTS: Women in MMT showed significant reductions in perceived stress (ß = - 0.16) and depressive symptoms (ß = - 0.21) compared to the treatment as usual (TAU) control group. Consistent with national norms, the majority of women (68%) gained excessive weight according to Institute of Medicine weight-gain categories, regardless of group. Slightly more women in the MMT group gained below the recommendation. Among secondary outcomes, women in MMT reported increased physical activity (ß = 0.26) and had lower glucose post-oral glucose tolerance test (ß = - 0.23), being 66% less likely to have impaired glucose tolerance, compared to the TAU group. CONCLUSION: A short-term intervention led to significant improvements in stress, and showed promise for preventing glucose intolerance. However, the majority of women gained excessive weight. A longer more intensive intervention may be needed for this high-risk population. Clinical Trials.gov #NCT01307683.


Asunto(s)
Glucemia/metabolismo , Atención Plena/métodos , Complicaciones del Embarazo/terapia , Aumento de Peso/fisiología , Adulto , Depresión/terapia , Dieta Saludable/psicología , Femenino , Humanos , Hiperfagia/terapia , Obesidad/terapia , Sobrepeso/terapia , Proyectos Piloto , Pobreza , Embarazo , Adulto Joven
2.
Matern Child Health J ; 22(5): 670-678, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29455384

RESUMEN

Background High stress and depression during pregnancy are risk factors for worsened health trajectories for both mother and offspring. This is also true for pre-pregnancy obesity and excessive gestational weight gain. Reducing stress and depression may be one path to prevent excessive caloric intake and gestational weight gain. Study Purpose We tested the feasibility of two novel interventions aimed at reducing stress and overeating during pregnancy. Reflecting different theoretical underpinnings, the interventions target different mechanisms. Mindful Moms Training (MMT) uses mindfulness to improve awareness and acceptance of experiences and promote conscious rather than automatic behavior choices. Emotional Brain Training (EBT) uses active coping to change perceptions of negative experience and promote positive affective states. Methods Forty-six overweight/obese low-income women were assigned to either MMT (n = 24) or EBT (n = 22) for an 8-week feasibility study. Pre-post changes in perceived stress, eating and presumed mechanisms were assessed. Results Women reported high levels of stress at baseline. Both interventions were well attended and demonstrated clinically significant pre-post reductions in stress, depressive symptoms, and improved eating behaviors. MMT significantly decreased experiential avoidance, whereas EBT significantly increased positive reappraisal; these changes were marginally significantly different by group. Conclusions This feasibility study found that both interventions promoted meaningful reductions in stress and depressive symptoms and improved reported eating behaviors in a high-risk group of pregnant women. Each intervention has a potentially different pathway-acceptance for MMT and reappraisal for EBT. Larger studies are needed to test efficacy on longer term reductions in stress and overeating.


Asunto(s)
Depresión/terapia , Conducta Alimentaria/psicología , Hiperfagia/terapia , Atención Plena/métodos , Complicaciones del Embarazo/terapia , Mujeres Embarazadas/psicología , Estrés Psicológico/terapia , Adolescente , Adulto , Depresión/psicología , Emociones , Estudios de Factibilidad , Femenino , Humanos , Hiperfagia/psicología , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/prevención & control , Sobrepeso/complicaciones , Sobrepeso/prevención & control , Embarazo , Complicaciones del Embarazo/psicología , Estrés Psicológico/psicología , Resultado del Tratamiento , Adulto Joven
3.
Am J Transplant ; 16(6): 1909-16, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26751054

RESUMEN

Metabolic syndrome is associated with long-term morbidity and mortality after adult liver transplantation (LT). Whether pediatric LT recipients have a higher prevalence of metabolic syndrome remains controversial. In a cross-sectional study, we evaluated pediatric LT recipients aged 8-30 years using National Health and Nutrition Examination Survey (NHANES) protocols. LT recipients were matched by gender, race/ethnicity, and age with controls from NHANES. Pediatric LT recipients (n = 83), after adjusting for overweight/obesity and glucocorticoid use, had increased prevalence of prehypertension and hypertension, impaired glucose tolerance (IGT; 2-h glucose after oral glucose tolerance test ≥140 mg/dL), and low high-density lipoprotein compared to matched NHANES controls (n = 235) despite a lower prevalence of overweight/obesity. Among LT recipients, the adjusted odds of IGT doubled for every 7.5 years taking calcineurin inhibitors (odds ratio = 2.10, 95% confidence interval 1.06-4.17 per 7.5 years taking calcineurin inhibitors, p = 0.03). Among all subjects with IGT, LT recipients had a lower prevalence of overweight/obesity and less insulin resistance (homeostatic model assessment of insulin resistance) than did controls with IGT. Among normal weight subjects, LT recipients were significantly more likely than controls to have prehypertension/hypertension, IGT, low high-density lipoprotein, and metabolic syndrome. Pediatric LT recipients have unique metabolic syndrome profiles and risk factors and will require tailored screening and management protocols.


Asunto(s)
Terapia de Inmunosupresión/efectos adversos , Trasplante de Hígado/efectos adversos , Síndrome Metabólico/etiología , Obesidad/fisiopatología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Síndrome Metabólico/patología , Prevalencia , Factores de Riesgo , Estados Unidos/epidemiología , Adulto Joven
4.
Hum Reprod Open ; 2023(2): hoad013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37265937

RESUMEN

STUDY QUESTIONS: The primary objective of this study is to determine what parental factors or specific ART may influence the risk for adverse cardiometabolic outcomes among children so conceived and their parents. The secondary objective of this study is to prospectively examine the effects of infertility or ART on the intrauterine environment, obstetric and neonatal outcomes. WHAT IS KNOWN ALREADY: Pregnancies conceived with ART are at an increased risk of being affected by adverse obstetric and neonatal outcomes when compared to spontaneously conceived (SC) pregnancies among fertile women. Small cohort studies have suggested ART-conceived children may have a higher risk of long-term cardiometabolic disturbances as well. Currently, few studies have compared long-term cardiometabolic outcomes among ART-conceived children and non-IVF treated (NIFT) children, to children conceived spontaneously to parents with infertility (subfertile parents). STUDY DESIGN SIZE DURATION: The Developmental Epidemiological Study of Children born through Reproductive Technologies (DESCRT) is a prospective cohort study that aims to: establish a biobank and epidemiological cohort of children born to subfertile or infertile parents who either conceived spontaneously (without assistance) or used reproductive technologies to conceive (all offspring were from couples assessed and/or treated in the same institute); prospectively examine the effects of infertility or ART on the intrauterine environment, obstetric and neonatal outcomes; and determine what parental factors or ART may influence the cardiometabolic risk of children so conceived. Pregnancies and resultant children will be compared by mode of conception, namely offspring that were conceived without medical assistance or SC or following NIFT, IVF with fresh embryo transfer or frozen embryo transfer (FET), and by fertilization method (conventional versus ICSI). DESCRT has a Child group evaluating long-term outcomes of children as well as a Pregnancy group that will compare obstetric and neonatal outcomes of children conceived since the commencement of the study. Recruitment started in May of 2017 and is ongoing. When the study began, we estimated that ∼4000 children would be eligible for enrollment. PARTICIPANTS/MATERIALS SETTING METHODS: Eligible participants are first-trimester pregnancies (Pregnancy group) or children (Child group) born to parents who were evaluated at an infertility center in the University of California, San Francisco, CA, USA who were SC or conceived after reproductive treatments (NIFT, IVF ± ICSI, FET). Children in the Child group were conceived at UCSF and born from 2001 onwards. In the Pregnancy group, enrollment began in November of 2017.The primary outcome is the cardiometabolic health of offspring in the Child group, as measured by blood pressure and laboratory data (homeostatic model assessment for insulin resistance (HOMA-IR), oral glucose disposition). There are several secondary outcome measures, including: outcomes from parental survey response (assessing parent/child medical history since delivery-incidence of cardiometabolic adverse events), anthropomorphic measurements (BMI, waist circumference, skinfold thickness), and laboratory data (liver enzymes, lipid panel, metabolomic profiles). In the Pregnancy group, outcomes include laboratory assessments (bhCG, maternal serum analytes, soluble fms-like tyrosine kinase-1 (sFLT-1), and placental growth factor (PlGF)) and placental assessments (placental volume in the second and third trimester and placental weight at delivery). Importantly, aliquots of blood and urine are stored from parents and offspring as part of a biobank. The DESCRT cohort is unique in two ways. First, there is an extensive amount of clinical and laboratory treatment data: parental medical history and physical examination at the time of treatment, along with ovarian reserve and infertility diagnosis; and treatment specifics: for example, fertilization method, culture O2 status, embryo quality linked to each participant. These reproductive data will aid in identifying explanatory variables that may influence the primary cardiometabolic outcomes of the offspring-and their parents. Second, the DESCRT control group includes pregnancies and children SC from parents with subfertility, which may help to assess when infertility, as opposed to reproductive treatments, may be affecting offspring cardiometabolic health. STUDY FUNDING/COMPETING INTERESTS: This study is funded by the National Institutes of Health NICHD (1R01HD084380-01A1). A.J.A. is a shareholder in Carrot and consultant for Flo Health. The other authors have no conflicts of interest. TRIAL REGISTRATION NUMBER: NCT03799107. TRIAL REGISTRATION DATE: 10 January 2019. DATE OF FIRST PATIENT'S ENROLLMENT: 10 May 2017.

5.
Int J Obes (Lond) ; 35(3): 457-61, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20733581

RESUMEN

Bariatric surgery is often successful for treatment of severe obesity. The mechanisms of weight loss after bariatric surgery and the role of central energy homeostatic pathways in this weight loss process are not well understood. The study of individuals with complete loss of function of genes important in the leptin-melanocortin system may help establish the significance of these pathways for weight loss after bariatric surgery. We describe the outcome of bariatric surgery in an adolescent with compound heterozygosity and complete functional loss of both alleles of the melanocortin 4 receptor (MC4R). The patient underwent laparoscopic adjustable gastric banding and truncal vagotomy at years of age, which resulted in initial, but not long-term weight loss. Our experience with this patient suggests that complete MC4R deficiency impairs response to gastric banding and results in poor weight loss after this surgery.


Asunto(s)
Cirugía Bariátrica/métodos , Obesidad Mórbida/cirugía , Receptor de Melanocortina Tipo 4/deficiencia , Pérdida de Peso/fisiología , Adolescente , Humanos , Masculino , Obesidad Mórbida/genética , Resultado del Tratamiento , Pérdida de Peso/genética
6.
Leukemia ; 15(5): 728-34, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368432

RESUMEN

We assessed the clinical and treatment factors that predispose survivors of childhood acute lymphoblastic leukemia (ALL) to low bone mineral density (BMD). Using quantitative computed tomography, we determined the frequency of low BMD (defined as >1.645 standard deviations (SD) below the mean) in leukemia survivors treated with multiagent chemotherapy including prednisone and antimetabolite. All participants had completed therapy at least 4 years earlier, remained in continuous complete remission, and had no second malignancies. We statistically correlated BMD results with patient characteristics and treatment histories. Among 141 survivors (median age, 15.9 years; median time after diagnosis, 11.5 years), median BMD z score was -0.78 SD (range, -3.23 to 3.61 SDs). Thirty participants (21%; 95% confidence interval, 15% to 29%) had abnormally low BMD, a proportion significantly (P < 0.0001) greater than the expected 5% in normal populations. Risk factors for BMD decrements included male sex (P = 0.038), Caucasian race (P < 0.0001), and cranial irradiation (P= 0.0087). BMD inversely correlated with cranial irradiation dose. BMD z scores of patients who received higher doses of antimetabolites were lower than those of other patients. Childhood ALL survivors are at risk to have low BMD, especially males, Caucasians, and those who received cranial irradiation.


Asunto(s)
Densidad Ósea , Enfermedades Óseas Metabólicas/etiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Adolescente , Antimetabolitos Antineoplásicos/efectos adversos , Estatura , Niño , Preescolar , Irradiación Craneana/efectos adversos , Femenino , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Lactante , Masculino , Factores de Riesgo , Sobrevivientes
7.
Endocrinology ; 124(4): 1863-9, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2924728

RESUMEN

Estradiol (E2) alters protein synthetic events in the ventromedial nucleus (VMN) of the hypothalamus to promote lordotic behavior in the female rat. This study analyzed the acute changes induced by E2 in proteins synthesized in the VMN in vivo as measured by 35S incorporation into protein, two-dimensional gel electrophoresis, autoradiography, and computerized optical densitometry. Ovariectomized rats received vehicle or E2, Hamilton syringes were placed stereotaxically in the VMN bilaterally, and 0.9 mCi 35S-labeled methionine and cysteine was infused over 1 h. After 6 h, rats were killed, and VMN samples were subjected to isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Resultant gels underwent autoradiography, and the optical density of each of 240 spots was quantitated using a flat-bed laser scanner. Using a quantitation algorithm based on the linearity and reproducibility of the scanner and film, 123 spots were analyzed for changes in optical density and relative mol wt (MW) and isoelectric point (pI) induced by E2. The spot induced most prominently by E2 had a MW of 70K and a pI of 6.0, confirming previous results. Three spots were quantitatively induced by E2: 1) a 47K MW, pI 5.4 phosphoprotein (96% induction); 2) a 45K MW, pI 5.2 protein (72% induction); and 3) a 100K MW, pI 5.5 protein (82% induction). Two spots increased pI with E2: 1) a 110K MW protein increased from pI 5.4 to 5.5; and 2) a 50K MW protein increased from pI 6.3 to 6.4. Under these conditions and using a quantitative algorithm, only a small number of proteins synthesized in the VMN were induced by E2 in vivo. E2 also exerts effects on the posttranslational modification of another select group of proteins. These proteins may subserve at least part of the physiological effect of E2 in the VMN.


Asunto(s)
Estradiol/farmacología , Proteínas del Tejido Nervioso/biosíntesis , Núcleo Hipotalámico Ventromedial/metabolismo , Animales , Autorradiografía , Electroforesis en Gel Bidimensional , Femenino , Proteínas del Tejido Nervioso/análisis , Sistemas Neurosecretores/fisiología , Ovariectomía , Ratas , Ratas Endogámicas , Núcleo Hipotalámico Ventromedial/análisis
8.
Endocrinology ; 125(5): 2701-9, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2792004

RESUMEN

16 alpha-Hydroxyestrone (16OHE1), an endogenous metabolite of estradiol (E2), binds to the estrogen receptor (ER) with low affinity, but is estrogenic in various bioassay systems. 16OHE1 binds covalently to the ER in vitro, exhibits prolonged estrogenic bioactivity in vivo, and has been implicated in several estrogen-dependent diseases. This study examined the effects of 13 days of continuous infusion of E2 or 16OHE1 on lordotic behavior, pituitary growth, and ER regulation in the cytosolic and nuclear fractions of the pituitary and preoptic area of both sexes. Finally, simultaneous pituitary nuclear exchange assays and enzyme immunoassays were performed to search for covalent 16OHE1-ER complexes in vivo. E2 induced lordosis and pituitary growth in both sexes, while 16OHE1 was only slightly less effective. While E2 treatment increased nuclear ER concentrations 2-fold vs. control values, it decreased both cytosolic and total (cytosolic plus nuclear) ER concentrations in pituitary and preoptic area by approximately 3-fold vs. control values in both sexes by exchange assay. In contrast, 16OHE1 did not decrease total pituitary ER concentrations and only minimally decreased total preoptic ER concentrations. Simultaneous exchange assay and immunoassay of pituitary nuclear extracts demonstrated proportionate increases in ER levels in female vs. male and in E2-treated vs. 16OHE1-treated rats. The ratios of (ER enzyme immunoassay divided by ER-exchange) for each rat were similar regardless of metabolite administration. The correlation of individual measurements implied that ER localized to the nuclear fraction by either E2 or 16OHE1 retained both exchangeability and immunoassayability to similar extents, but did not support the presence of 16OHE1-ER covalent complexes. The results of this study suggest that 16OHE1 has significant estrogenic bioactivity, as manifest by its effects on lordosis and pituitary growth, but, in contrast to E2, does not decrease pituitary ER concentrations and only minimally decreases preoptic ER concentrations. This property may be important in the proposed pathogenetic action of 16OHE1 in estrogen-dependent disease.


Asunto(s)
Estradiol/farmacología , Estrona/análogos & derivados , Hidroxiestronas/farmacología , Hipófisis/fisiología , Área Preóptica/fisiología , Receptores de Estrógenos/fisiología , Envejecimiento , Animales , Núcleo Celular/metabolismo , Citosol/metabolismo , Femenino , Masculino , Orquiectomía , Ovariectomía , Hipófisis/efectos de los fármacos , Hipófisis/crecimiento & desarrollo , Postura , Área Preóptica/efectos de los fármacos , Ratas , Ratas Endogámicas F344 , Receptores de Estrógenos/efectos de los fármacos , Conducta Sexual Animal
9.
J Clin Endocrinol Metab ; 58(6): 1043-9, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6427257

RESUMEN

Synthetic, amidated, 44 amino acid GH-releasing hormone ( GRH -44) was administered iv at a dose of 5 micrograms/kg to 20 patients with severe GH deficiency (GHD), 6 children and adolescents with partial GHD, and 6 non-GH deficient ( NGHD ) children and adolescents. The 17 patients with severe GHD that responded to GRH -44 had lower peak concentrations of plasma GH than the NGHD individuals (5.0 +/- 1.2 (SEM) vs. 27.2 +/- 3.5 ng/ml; P less than 0.0001). The children and adolescents with severe GHD tended to have higher peak GH responses to GRH -44 than the GHD adults (6.9 +/- 1.7 vs. 2.4 +/- 0.3 ng/ml) although the difference was not significant. The peak GH concentration was attained earlier in the GHD children and adolescents than in the GHD adults (28 +/- 4.7 vs. 69.3 +/- 13 min, P less than 0.004). There was a negative correlation between chronological age and peak plasma GH response to GRH in the children and adolescents with severe GHD (r = -0.758, P less than 0.02). Children and adolescents with partial GHD had a higher mean peak concentration of plasma GH (13. 1 +/- 1.8 ng/ml) than the children, adolescents, and adults with severe GHD (P less than 0.04), but one lower than the NGHD children and adolescents (P less than 0.05). In both severe and partial GHD the GH response to GRH was greater than that elicited by standard pharmacological tests. Serum somatomedin-C did not increase after a single pulse of GRH -44 in the 12 GHD patients studied. PRL increased minimally 30 min after 5 micrograms/kg iv GRH -44 in patients with multiple hypothalamic-pituitary hormone deficiencies but not in patients with isolated GHD or in NGHD individuals. The GH responses to GRH suggest that the majority of patients with isolated GHD as well as those with multiple hypothalamic-pituitary hormone deficiencies have deficiency of hypothalamic GRH . Lack of a GH response to a single pulse of GRH does not exclude GRH deficiency as priming of the somatotrope with multiple pulses of GRH may be necessary to rule out a hypothalamic defect in the nonresponders. The results of this study support the potential usefulness of GRH or its analogs in the diagnosis and treatment of selected patients with disorders of GH secretion.


Asunto(s)
Hormona Liberadora de Hormona del Crecimiento , Hormona del Crecimiento/deficiencia , Hormonas Hipofisarias/deficiencia , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Femenino , Hormona del Crecimiento/sangre , Humanos , Hipotálamo/metabolismo , Masculino
10.
J Clin Endocrinol Metab ; 84(12): 4472-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10599705

RESUMEN

To determine how often central hypothyroidism remains undetected by routine out-patient tests of thyroid hormone, we studied 208 pediatric cancer survivors referred for evaluation because of signs of subtle hypothyroidism or hypopituitarism. Of the 208 (68 females and 140 males), 110 had brain tumors, 14 had other head/neck tumors, 11 had solid tumors remote from head and neck, and 73 had leukemia. Patients were evaluated 1-16 yr (mean, 6.1+/-4.1 yr) after tumor diagnosis. The nocturnal TSH surge and response to TRH were measured. Of 160 patients with free T4 in lowest third of normal, 34% had central hypothyroidism (blunted TSH surge or low/delayed TSH peak or delayed TSH decline after TRH); 9% had central hypothyroidism with mild TSH elevation (mixed hypothyroidism). Another 16% had mild primary hypothyroidism (TSH, 5-15 mU/L). Of 48 with free T4 in the upper two thirds of normal, 14% had central hypothyroidism; 17% had mild primary hypothyroidism. Incidence of central, mixed, and mild primary hypothyroidism 10 yr after tumor diagnosis was significantly related to total cranial radiation dose (P < 0.0001). Of 62 patients with central hypothyroidism, 34% had not developed GH deficiency. TSH surge identified 71%, and response to TRH identified 60% of those with central hypothyroidism. More than half of the slowly growing patients who have received cranial or craniospinal radiation for childhood cancer develop subtle hypothyroidism. In our study group, 92% of patients with central hypothyroidism and 27% with mixed hypothyroidism would have remained undiagnosed using baseline thyroid function tests alone. Both TSH surge and response to TRH must be evaluated to identify all of these patients.


Asunto(s)
Hipotiroidismo/diagnóstico , Neoplasias/complicaciones , Adolescente , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/radioterapia , Niño , Preescolar , Femenino , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Hipotiroidismo/etiología , Lactante , Leucemia/complicaciones , Leucemia/terapia , Masculino , Neoplasias/radioterapia , Radioterapia/efectos adversos , Tirotropina/sangre , Hormona Liberadora de Tirotropina , Tiroxina/sangre
11.
Endocrinol Metab Clin North Am ; 30(3): 765-85, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11571940

RESUMEN

The regulation of energy balance is enormously complex, with numerous genetic, hormonal, neural/behavioral, and societal influences. Although the current epidemic of obesity has its underpinnings in the changes in culture during the last half century, the role of the neuroendocrine system in the genesis of obesity is physiologically and therapeutically unavoidable. Increased understanding of this system has suggested organic etiologies (and therapies) for some rare and not-so-rare forms of obesity. With so many inputs, it is not implausible that dysfunction of other parts of this feedback system will be found to explain other forms of obesity in the future. Fortunately or unfortunately, diet and exercise remain the mainstays of obesity therapy. Most diet-exercise programs result in an acute 11-kg weight loss in adults; the question is whether it can be sustained without significant long-term behavior modification. In the European Sibutramine Trial of Obesity Reduction and Maintenance (STORM), 42% of treated patients dropped out; of those remaining, 77% of subjects lost more than 5% of initial body weight, but only 43% of these individuals maintained greater than 80% of this loss over 2 years. Could there be an organic component in persons who do not respond? Obesity pharmacotherapies sometimes have beneficial acute effects, but these effects are impermanent; discontinuation tends to result in a rebound weight gain, suggesting that the etiology of the obesity is still present. A useful guiding principle is that patients who do not respond to diet and exercise should undergo an initial medical evaluation, including assessments of birth weight, past medical history, weight history, family history, diet, exercise, and fasting insulin and thyroid levels. As the nosology of obesity improves, diagnostic efficiency and therapeutic success should increase, leading to a decrease in associated morbidity, mortality, and socioeconomic ramifications.


Asunto(s)
Sistemas Neurosecretores/fisiopatología , Obesidad/fisiopatología , Animales , Metabolismo Energético/fisiología , Hormonas/fisiología , Humanos , Sistemas Neurosecretores/metabolismo , Obesidad/metabolismo
12.
Pediatrics ; 76(2): 274-9, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3927254

RESUMEN

Five male children who received cranial irradiation for extrahypothalamic intracranial neoplasms or leukemia and subsequently developed severe growth hormone (GH) deficiency were challenged with synthetic growth hormone-releasing factor (GRF-44), in an attempt to distinguish hypothalamic from pituitary dysfunction as a cause of their GH deficiency, and to assess the readily releasable GH reserve in the pituitary. In response to a pulse of GRF-44 (5 micrograms/kg intravenously), mean peak GH levels rose to values higher than those evoked by the pharmacologic agents L-dopa or arginine (6.4 +/- 1.3 ng/mL v 1.5 +/- 0.4 ng/mL, P less than .05). The peak GH value occurred at a mean of 26.0 minutes after administration of GRF-44. These responses were similar to those obtained in children with severe GH deficiency due to other etiologies (peak GH 6.3 +/- 1.7 ng/mL, mean 28.0 minutes). In addition, there was a trend toward an inverse relationship between peak GH response to GRF-44 and the postirradiation interval. Prolactin and somatomedin-C levels did not change significantly after the administration of a single dose of GRF-44. The results of this study support the hypothesis that cranial irradiation in children can lead to hypothalamic GRF deficiency secondary to radiation injury of hypothalamic GRF-secreting neurons. This study also lends support to the potential therapeutic usefulness of GRF-44 or an analog for GH deficiency secondary to cranial irradiation.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Hormona Liberadora de Hormona del Crecimiento , Hormona del Crecimiento/deficiencia , Leucemia Linfoide/radioterapia , Fragmentos de Péptidos , Adenohipófisis/efectos de la radiación , Traumatismos por Radiación/sangre , Adolescente , Niño , Preescolar , Enanismo Hipofisario/sangre , Hormona del Crecimiento/sangre , Humanos , Factor I del Crecimiento Similar a la Insulina , Masculino , Prolactina/sangre , Dosificación Radioterapéutica , Somatomedinas/sangre
13.
J Endocrinol ; 116(1): 55-69, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3339293

RESUMEN

Sex steroids convey information on the status of the reproductive system, which the brain is able to integrate to promote ovulation, in the form of the LH surge. The present studies examined the influence of alterations in central opioidergic tone to initiate the LH surge, and the roles of oestradiol and progesterone to effect changes in opioidergic tone, by antagonizing this activity using either naloxone or nalmefene (N-cyclopropylmethyl-6-desoxy-6-methylene-noroxy-morphone), a long-acting mu- and kappa-opiate antagonist. The timing and amplitude of the LH surge was examined in (1) cyclic rats in pro-oestrus and (2) ovariectomized rats with varying doses of oestradiol supplementation. Plasma was obtained hourly through an indwelling intra-atrial catheter between 13.00 and 19.00 h, and later assayed for LH and oestradiol concentrations by radioimmunoassay. Rats treated with either nalmefene or progesterone on pro-oestrus demonstrated similar advances in the time of initiation of the LH surge by 1-2 h compared with control rats. The effects of nalmefene and progesterone were evident within 2 and 3-5 h of their administration respectively. Conversely, rats treated with progesterone on dioestrus demonstrated low pro-oestrous oestradiol levels and abolition of the pro-oestrous LH surge, but continuous naloxone infusion restored the pro-oestrous LH surge, with raised oestradiol concentrations. In ovariectomized rats without oestradiol supplentation, nalmefene alone was able to increase basal LH levels, but unable to facilitate a spontaneous rise in LH amplitude indicative of an LH surge. Supplementation with low doses of oestradiol was itself ineffective in facilitating a spontaneous rise in LH concentration, but nalmefene co-administration significantly potentiated the ability of low doses of oestradiol to induce augmented LH secretion, in addition to advancing the timing of the spontaneous LH rise. Similarly, progesterone co-administration to ovariectomized, oestradiol-primed rats significantly advanced and augmented LH hypersecretion. The results of these experiments are consistent with the concept that central opioidergic systems normally restrain the initiation of the LH surge, and that blocking opiate receptors removes this inhibition. They advance the hypothesis that oestradiol, the essential signal for LH surge induction, has, as one consequence of its action, the time-specific inhibition of hypothalamic opiodergic tone in the afternoon, which would otherwise restrain the LH surge-generating mechanism.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Estradiol/farmacología , Hormona Luteinizante/sangre , Naloxona/farmacología , Naltrexona/análogos & derivados , Animales , Diestro/efectos de los fármacos , Femenino , Naltrexona/farmacología , Ovariectomía , Proestro/efectos de los fármacos , Progesterona/farmacología , Ratas , Ratas Endogámicas
14.
J Endocrinol ; 117(2): 229-35, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3379356

RESUMEN

The pro-oestrous secretion of progesterone that follows the LH surge in the rat limits the expression of the daily signal for LH surge initiation until the following oestrous cycle. This study explored the role of endogenous opioid peptides in the extinction by progesterone of the signal for the LH surge induced by oestrogen. Intact cyclic rats underwent external jugular venous cannulation on dioestrus, and were allowed to elicit a spontaneous pro-oestrous LH surge. On the afternoon of pro-oestrus, rats received an s.c. injection of oestradiol and an s.c. injection of either oil, 17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)17 alpha-(prop-1-ynyl)oestra-4,9,dien-3-one (RU 486; a synthetic anti-progestin), or N-cyclopropylmethyl-6-desoxy-6-methylene-noroxy-morphone (nalmefene; a long-acting opiate antagonist). Repeat doses of each were administered on the morning of oestrus to maintain increased oestrogen levels, and either progesterone or opioidergic blockade. Plasma was obtained from 13.00 to 19.00 h on oestrus for determination of the concentration of rat LH. Rats treated with oestradiol alone demonstrated consistently low concentrations of LH throughout the afternoon of oestrus. Rats treated with both oestradiol and either RU 486 or nalmefene demonstrated spontaneous augmentations of rat LH concentration during the afternoon of oestrus, which, although of diminished amplitude as compared with that seen in pro-oestrus, were consistent with a reactivation of the LH surge-generating mechanism. Rats treated with nalmefene in the absence of oestradiol were unable to augment LH secretion spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Estrenos/farmacología , Estro/sangre , Hormona Luteinizante/metabolismo , Naltrexona/análogos & derivados , Proestro/sangre , Progestinas/antagonistas & inhibidores , Animales , Estradiol/farmacología , Femenino , Mifepristona , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Progesterona/sangre , Ratas , Ratas Endogámicas , Tasa de Secreción/efectos de los fármacos , Estimulación Química
15.
Brain Res Mol Brain Res ; 11(2): 125-32, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1661809

RESUMEN

In addition to effects on brain protein synthesis, neurotransmitter release, and electrophysiology, estrogens alter neurite outgrowth and synaptogenesis. This study examined in the adult rat the effects of estrogen and sex on the expression of the GAP-43 gene; encoding a phosphoprotein structurally and physiologically linked to these two processes in the rat CNS. Ovariectomized (OVX) rats were injected with vehicle or estrogen, or male and female rats were either gonadectomized or left intact. Brains were dissected to obtain ventromedial hypothalamus (VMH), posterior hypothalamus (PH), or frontal cortex (CTX). Total RNA from these areas were extracted, and slot-blots of equal masses of total RNA were hybridized to 32P-labeled cDNAs for GAP-43 and beta-actin, and also to synthetic poly-dT. Resultant autoradiograms were scanned by laser densitometry, quantitated, and ratios of the gray scale generated by each probe were compared between experimental groups. GAP-43 mRNA expression, when compared to expression of either beta-actin mRNA or total poly(A)-containing RNA (poly(A) RNA), was higher in VMH and PH as compared to CTX. Estrogen treatment of OVX rats resulted in a 48-74% increase in GAP-43 mRNA levels in the VMH--in one experiment, this increase was noted after 2 h of estradiol treatment, and in another after 3 days of estradiol benzoate treatment; but PH and CTX were unaffected by either estrogen regimen. Conversely, ovariectomy of intact rats decreased GAP-43 mRNA expression by 45% in the VMH, but not in the CTX.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Estrógenos/fisiología , Glicoproteínas de Membrana/genética , Proteínas del Tejido Nervioso/genética , ARN Mensajero/metabolismo , Caracteres Sexuales , Animales , Densitometría , Femenino , Proteína GAP-43 , Regulación de la Expresión Génica/fisiología , Immunoblotting , Masculino , Plasticidad Neuronal/fisiología , Ratas , Ratas Endogámicas , Sinapsis/fisiología
16.
Brain Res Mol Brain Res ; 20(1-2): 101-10, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8255171

RESUMEN

Sex hormones influence neurite outgrowth and synaptogenesis in certain hormone-dependent areas of the rat brain during neonatal development. These alterations are thought to mediate changes in brain structure and function between the sexes. Growth-associated protein 43 kDa (GAP-43) gene expression is estrogen-regulated in the adult ventromedial hypothalamus (VMH) and sexually dimorphic (M:F = 1.8:1) in adult cortex (CTX). Such effects intimate hormonal regulation of synaptic plasticity. To investigate the nature of these dimorphisms, the present study examined the ontogeny of expression of mRNAs encoding 3 neural-specific proteins: GAP-43, SCG10, and synaptosomal-associated protein 25 kDa (SNAP-25); and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in the VMH and CTX; and also the effects of altering the neonatal sex hormonal milieu on the development of these adult dimorphisms. Levels of specific mRNAs in VMH and CTX were quantitated by slot-blot hybridization in rats of both sexes at different postnatal ages. To determine the involvement of neonatal sex hormones on the levels of these mRNAs, male neonatal rat pups were treated with an estrogen receptor antagonist or an aromatase inhibitor, and neonatal female pups were treated with testosterone or estrogen prior to slot-blot evaluations in adulthood. In VMH, GAP-43 mRNA levels were high on days P1 and P4 with a 3-fold decrease by day P23; in CTX, GAP-43 mRNA first increased by day P11, then fell to baseline by day P23. In VMH, SCG10 mRNA showed only small increases with time; but in CTX, there was a 5-fold drop from days P4 to P23. In VMH, SNAP-25 mRNA was low and changed only slightly; but in CTX there was a 5-fold increase between days P4 and P60. At birth, there was no sex dimorphism in either VMH or CTX, but the levels of all 3 neural-specific mRNAs were sexually dimorphic in adult CTX (M:F = 1.76 for GAP-43, 1.46 for SCG10, 1.44 for SNAP-25). GAPDH mRNA levels were regulated developmentally in VMH and CTX, but there was no sex dimorphism in either area. In male rats who received either an estrogen antagonist or aromatase inhibitor at birth, the CTX GAP-43 and SNAP-25 mRNA levels fell by 30%, to levels similar to untreated females. Conversely, in female rats, neonatal treatment with either testosterone or estrogen increased GAP-43 and SNAP-25 mRNA levels by about 30%, to levels similar to the untreated adult male. SCG10 levels did not demonstrate neonatal hormonal dependence.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Encéfalo/crecimiento & desarrollo , Hormonas Esteroides Gonadales/metabolismo , ARN Mensajero/metabolismo , Caracteres Sexuales , Sinapsis/metabolismo , Animales , Animales Recién Nacidos/metabolismo , Encéfalo/metabolismo , Corteza Cerebral/metabolismo , Femenino , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Hipotálamo Medio/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley
17.
Ann N Y Acad Sci ; 784: 370-80, 1996 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-8651585

RESUMEN

The results of these two in vitro models share some striking similarities. In both, estrogen was able to induce or promote the formation of either dendrites themselves in hippocampal neurons or dendritic specializations in PC12 neurites, and these specializations were then able to induce interneural interactions. In both models, androgen was able to promote the development of axons that branched frequently, while not directly fostering interneuronal contact. These findings recapitulate in part some of the effects of estrogen and androgen on neurons in vivo and suggest the inherent ability of cells of neural crest origin to respond to these hormones with specific neural morphogenetic programs designed to alter interneuronal communication. In these ways, it seems likely that both sex hormones are acting as neural growth factors in cells that express the appropriate receptor, leading to stereotyped changes in neural growth and pattern formation. Through the examination of such subcellular mechanisms, we hope to further understand the effects of sex hormones on brain development and the ontogeny of behavioral, cognitive, and reproductive differences between the sexes.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Hormonas Esteroides Gonadales/fisiología , Neuronas/citología , Animales , Encéfalo/citología , Encéfalo/fisiología , Células Cultivadas , Humanos , Neuronas/fisiología , Células PC12 , Ratas
18.
J Neurosci Methods ; 29(1): 17-26, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2761295

RESUMEN

Two-dimensional (2-D) gel electrophoresis has been used in conjunction with autoradiography and computerized optical densitometry for quantitating specific protein synthesis. However, accurate quantitation of 2-D autoradiograms requires the prior assessment of such parameters as linearity, reciprocity, and reproducibility. The present study was performed to determine the contribution of each of these to the dissimilation of beta-emission and autoradiographic density, and of density and protein synthesis. Various aliquot volumes of a single complex protein specimen labeled with 35S-amino acids were subjected to 2-D gel electrophoresis, and these gels were serially exposed at graded intervals. The peak densities and volumes of the 111 visualized spots were used to examine the above parameters. In our computerized scanning system, the peak density is a more accurate and reproducible parameter of optical density than is spot volume. Approximately 30% of the dynamic range of peak density is non-linear; quantitation of spots above or below the linear range leads to inaccuracies in quantitation. In addition, the phenomenon of reciprocity, which states that density is directly proportional to exposure (beta-emission of 35S x time), is shown to fail as aliquot volume, or mass of 35S increases. The implications of reciprocity failure to accurate quantitation are discussed. Finally, the sources of variance in autoradiographic analysis were examined, by assessing the intra-scan, intra-gel run, and inter-gel run coefficients of variation. The results of this study show that autoradiographic densitometry is an effective method for quantitation of 2-D gels, but linearity, reciprocity, and reproducibility must be assessed prior to its experimental use. Restrictions of such use are suggested.


Asunto(s)
Autorradiografía/métodos , Electroforesis en Gel de Agar/métodos , Electroforesis/métodos , Proteínas del Tejido Nervioso/análisis , Núcleo Hipotalámico Ventromedial/análisis , Animales , Femenino , Proteínas del Tejido Nervioso/biosíntesis , Ratas , Ratas Endogámicas
19.
Pediatr Clin North Am ; 48(4): 909-30, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11494643

RESUMEN

The regulation of energy balance is enormously complex, with numerous genetic, hormonal, neural and behavioral, and societal influences. Although the current epidemic of obesity clearly has its underpinnings in the changes in culture during the past half-century (see other articles in this issue), the role of the neuroendocrine system in the genesis of obesity, as described in this article, is physiologically and therapeutically unavoidable. An understanding of this system has suggested organic causes (and therapies) for some rare and not-so-rare forms of obesity. With so many inputs, it is not far-fetched to assume that dysfunction of other parts of this feedback system will be found to explain other forms of obesity in the future. What does this mean for obese children entering the pediatrician's office? Fortunately or unfortunately, diet and exercise are the mainstays of obesity therapy for children and adults. Most diet-exercise programs result in an acute 11-kg weight loss in adults; the question is whether it can be sustained without significant long-term behavioral modification. For instance, the European Sibutramine Trial of Obesity Reduction and Maintenance trial showed that 42% of treated subjects drop out; of those remaining, 77% of subjects lost more than 5% of initial body weight, but only 43% of those maintained more than 80% of this over 2 years. Could there be an organic component in those who do not respond? Of course, obesity pharmacotherapies sometimes have beneficial acute effects, but these drugs work for only as long as they are consumed; discontinuation tends to result in a "rebound" weight gain, suggesting that the cause of the obesity is still present. Furthermore, in 2001, there are no obesity drugs approved for children. A useful guiding principle is that children deserve at the minimum an initial medical evaluation, including birth weight, medical history, family history, dietary evaluation, and exercise assessment. Perhaps the most important feature that can distinguish "organic" from "behavioral" weight gain in childhood is the age of the "adiposity rebound." The Centers for Disease Control and Prevention now supplies BMI charts for boys and girls at www.cdc.gov/growthcharts. Plotting of the BMI versus age allows pediatricians to determine the age at which the BMI starts to increase (mean, 5.5 years). The earlier the adiposity rebound, the more likely the child will be obese as an adult, and the more likely that an organic cause can be determined. In such patients, thyroid levels and fasting insulin and leptin levels should be measured. An initial attempt at diet and exercise is essential; patients who do not respond with BMI stabilization should be investigated for a more ominous cause of their obesity. As the nosology of obesity improves, pediatricians will be able to increase the diagnostic efficiency and therapeutic success of this unfortunate, debilitating, and expensive epidemic.


Asunto(s)
Sistemas Neurosecretores/fisiopatología , Obesidad/fisiopatología , Vías Aferentes , Regulación del Apetito , Niño , Vías Eferentes , Metabolismo Energético , Humanos , Insulina/metabolismo , Sistemas Neurosecretores/fisiología
20.
Obes Rev ; 13(9): 780-98, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22577758

RESUMEN

Hypothalamic obesity is an intractable form of obesity syndrome that was initially described in patients with hypothalamic tumours and surgical damage. However, this definition is now expanded to include obesity developing after a variety of insults, including intracranial infections, infiltrations, trauma, vascular problems and hydrocephalus, in addition to acquired or congenital functional defects in central energy homeostasis in children with the so-called common obesity. The pathogenetic mechanisms underlying hypothalamic obesity are complex and multifactorial. Weight gain results from damage to the ventromedial hypothalamus, which leads, variously, to hyperphagia, a low-resting metabolic rate; autonomic imbalance; growth hormone-, gonadotropins and thyroid-stimulating hormone deficiency; hypomobility; and insomnia. Hypothalamic obesity did not receive enough attention, as evidenced by rarity of studies in this group of patients. A satellite symposium was held during the European Congress of Obesity in May 2011, in Istanbul, Turkey, to discuss recent developments and concepts regarding pathophysiology and management of hypothalamic obesity in children. An international group of leading researchers presented certain aspects of the problem. This paper summarizes the highlights of this symposium. Understanding the central role of the hypothalamus in the regulation of feeding and energy metabolism will help us gain insights into the pathogenesis and management of common obesity.


Asunto(s)
Craneofaringioma/complicaciones , Enfermedades Hipotalámicas/complicaciones , Obesidad/etiología , Neoplasias Hipofisarias/complicaciones , Sistema Nervioso Autónomo/fisiopatología , Niño , Congresos como Asunto , Craneofaringioma/fisiopatología , Metabolismo Energético , Humanos , Enfermedades Hipotalámicas/fisiopatología , Neoplasias Hipotalámicas/complicaciones , Neoplasias Hipotalámicas/fisiopatología , Obesidad/prevención & control , Neoplasias Hipofisarias/fisiopatología , Síndrome de Prader-Willi/complicaciones , Síndrome de Prader-Willi/fisiopatología , Aumento de Peso
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