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1.
J Endocrinol Invest ; 39(6): 667-77, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27223400

RESUMEN

PURPOSE: We examined auxological changes in growth hormone (GH)-treated children in Italy using data from the Italian cohort of the multinational observational Genetics and Neuroendocrinology of Short Stature International Study (GeNeSIS) of pediatric patients requiring GH treatment. METHODS: We studied 711 children (median baseline age 9.6 years). Diagnosis associated with short stature was as determined by the investigator. Height standard deviation score (SDS) was evaluated yearly until final or near-final height (n = 78). Adverse events were assessed in all GH-treated patients. RESULTS: The diagnosis resulting in GH treatment was GH deficiency (GHD) in 85.5 % of patients, followed by Turner syndrome (TS 6.6 %). Median starting GH dose was higher in patients with TS (0.30 mg/kg/week) than patients with GHD (0.23 mg/kg/week). Median (interquartile range) GH treatment duration was 2.6 (0.6-3.7) years. Mean (95 % confidence interval) final height SDS gain was 2.00 (1.27-2.73) for patients with organic GHD (n = 18) and 1.19 (0.97-1.40) for patients with idiopathic GHD (n = 41), but lower for patients with TS, 0.37 (-0.03 to 0.77, n = 13). Final height SDS was >-2 for 94 % of organic GHD, 88 % of idiopathic GHD and 62 % of TS patients. Mean age at GH start was lower for organic GHD patients, and treatment duration was longer than for other groups, resulting in greater mean final height gain. GH-related adverse events occurred mainly in patients diagnosed with idiopathic GHD. CONCLUSIONS: Data from the Italian cohort of GeNeSIS showed auxological changes and safety of GH therapy consistent with results from international surveillance databases.


Asunto(s)
Estatura/efectos de los fármacos , Hormona de Crecimiento Humana/uso terapéutico , Síndrome de Turner/tratamiento farmacológico , Adolescente , Niño , Preescolar , Enanismo Hipofisario , Femenino , Humanos , Italia , Masculino , Seguridad del Paciente , Estudios Prospectivos , Resultado del Tratamiento
2.
Horm Metab Res ; 46(7): 515-20, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24799024

RESUMEN

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder mainly caused by defects in the 21-hydroxylase gene (CYP21A2), coding for the enzyme 21-hydroxylase (21-OH). About 95% of the mutations arise from gene conversion between CYP21A2 and the inactive pseudogene CYP21A1P: only 5% are novel CYP21A2 mutations, in which functional analysis of mutant enzymes has been helpful to correlate genotype-phenotype. In the present study, we describe 3 novel point mutations (p.L122P, p.Q481X, and p.E161X) in 3 Italian patients with CAH: the fourth mutation (p.M150R) was found in the carrier state. Molecular modeling suggests a major impact on 21-hydroxylase activity, and functional analysis after expression in COS-7 cells confirms reduced enzymatic activity of the mutant enzymes. Only the p.M150R mutation affected the activity to a minor extent, associated with NC CAH. CYP21A2 genotyping and functional characterization of each disease-causing mutation has relevance both for treatment and genetic counseling to the patients.


Asunto(s)
Hiperplasia Suprarrenal Congénita/enzimología , Hiperplasia Suprarrenal Congénita/genética , Mutación/genética , Esteroide 21-Hidroxilasa/química , Esteroide 21-Hidroxilasa/genética , Secuencia de Aminoácidos , Animales , Western Blotting , Células COS , Niño , Chlorocebus aethiops , Femenino , Genotipo , Humanos , Recién Nacido , Italia , Masculino , Datos de Secuencia Molecular , Proteínas Mutantes/metabolismo , Fenotipo , Estructura Secundaria de Proteína , Alineación de Secuencia
3.
J Exp Med ; 193(5): 585-93, 2001 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-11238589

RESUMEN

Neutrophils are markedly less sensitive to glucocorticoids than T cells, making it difficult to control inflammation in neutrophil-mediated diseases. Development of new antiinflammatory strategies for such diseases would be aided by an understanding of mechanisms underlying differential steroid responsiveness. Two protein isoforms of the human glucocorticoid receptor (GR) exist, GRalpha and GRbeta, which arise from alternative splicing of the GR pre-mRNA primary transcripts. GRbeta does not bind glucocorticoids and is an inhibitor of GRalpha activity. Relative amounts of these two GRs can therefore determine the level of glucocorticoid sensitivity. In this study, human neutrophils and peripheral blood mononuclear cells (PBMCs) were studied to determine the relative amounts of each GR isoform. The mean fluorescence intensity (MFI) using immunofluorescence analysis for GRalpha was 475 +/- 62 and 985 +/- 107 for PBMCs and neutrophils, respectively. For GRbeta, the MFI was 350 +/- 60 and 1,389 +/- 143 for PBMCs and neutrophils, respectively (P < 0.05). After interleukin (IL)-8 stimulation of neutrophils, there was a statistically significant increase in intensity of GRbeta staining to 2,497 +/- 140 (P < 0.05). No change in GRalpha expression was observed. This inversion of the GRalpha/GRbeta ratio in human neutrophils compared with PBMCs was confirmed by quantitative Western analysis. Increased GRbeta mRNA expression in neutrophils at baseline, and after IL-8 exposure, was observed using RNA dot blot analysis. Increased levels of GRalpha/GRbeta heterodimers were found in neutrophils as compared with PBMCs using coimmunoprecipitation/Western analysis. Transfection of mouse neutrophils, which do not contain GRbeta, resulted in a significant reduction in the rate of cell death when treated with dexamethasone.We conclude that high constitutive expression of GRbeta by human neutrophils may provide a mechanism by which these cells escape glucocorticoid-induced cell death. Moreover, upregulation of this GR by proinflammatory cytokines such as IL-8 further enhances their survival in the presence of glucocorticoids during inflammation.


Asunto(s)
Corticoesteroides/farmacología , Dexametasona/farmacología , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Receptores de Glucocorticoides/metabolismo , Animales , Western Blotting , Muerte Celular/efectos de los fármacos , Separación Celular , Células Cultivadas , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Expresión Génica , Humanos , Interleucina-8/farmacología , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Ratones , Ratones Endogámicos BALB C , Neutrófilos/citología , ARN Mensajero/metabolismo , Receptores de Glucocorticoides/análisis , Receptores de Glucocorticoides/genética , Especificidad de la Especie , Transfección
4.
J Exp Med ; 186(9): 1567-74, 1997 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-9348314

RESUMEN

In many chronic inflammatory disorders, glucocorticoid (GC) insensitivity is a challenging clinical problem associated with life-threatening disease progression. The molecular basis of GC insensitivity, however, is unknown. Alternative splicing of the GC receptor (R) pre-messenger RNA generates a second GCR, termed GCR-beta, which does not bind GCs but antagonizes the transactivating activity of the classic GCR, termed GCR-alpha. In the current study, we demonstrate that GC-insensitive asthma is associated with a significantly higher number of GCR-beta-immunoreactive cells in peripheral blood than GC-sensitive asthmatics or normal controls. Furthermore, we show that patients with GC-insensitive asthma have cytokine-induced abnormalities in the DNA binding capability of the GCR. These abnormalities can be reproduced by transfection of cell lines with the GCR-beta gene resulting in significant reduction of their GCR-alpha DNA binding capacity. We conclude that increased expression of GCR-beta is cytokine inducible and may account for GC insensitivity in this common inflammatory condition.


Asunto(s)
Glucocorticoides/farmacología , Receptores de Glucocorticoides/biosíntesis , Asma/tratamiento farmacológico , Asma/metabolismo , Línea Celular , Células Cultivadas , Proteínas de Unión al ADN/efectos de los fármacos , Proteínas de Unión al ADN/genética , Resistencia a Medicamentos , Electroforesis en Gel de Poliacrilamida , Glucocorticoides/antagonistas & inhibidores , Glucocorticoides/metabolismo , Humanos , Interleucina-2/farmacología , Interleucina-4/farmacología , Leucocitos Mononucleares/metabolismo , Receptores de Glucocorticoides/análisis , Receptores de Glucocorticoides/genética
5.
J Endocrinol Invest ; 31(8): 689-93, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18852528

RESUMEN

Isolated GH deficiency or combined pituitary hormone deficiencies have been associated with mutations in transcription factors encoding genes that control organogenesis or cell differentiation. Among these factors, Hesx1 is essential for the development of the optic nerve and regulates some of the earliest stages in pituitary development and is intimately involved in orchestrating the expression of other factors involved in pituitary organogenesis. Mutations in HESX1 are reported in patients with hypopituitarism either with typical septo-optic dysplasia (SOD) or with neuromorphological abnormalities not included in classical SOD. The present report describes clinical features, biochemical parameters, and characterization of a missense mutation (Gln6His) in exon1 of HESX1 in a pre-pubertal child who progressively developed multiple hypopituitarism, firstly GH and, afterwards, TSH and ACTH deficiencies, in a pluri-malformative syndrome characterized by short stature and anatomical malformations not associated with a classical SOD phenotype. This finding further supports the necessity to stay alert in evaluating a gene that plays a minor role in the pathogenesis of sporadic hypopituitarism, such as HESX1 gene even when the phenotype does not fit in with a classical SOD syndrome.


Asunto(s)
Anomalías Congénitas/genética , Proteínas de Homeodominio/genética , Hipopituitarismo/genética , Displasia Septo-Óptica/genética , Secuencia de Bases , Niño , Anomalías Congénitas/patología , Análisis Mutacional de ADN , Heterocigoto , Humanos , Hipopituitarismo/complicaciones , Hipopituitarismo/congénito , Masculino , Datos de Secuencia Molecular , Fenotipo , Mutación Puntual/fisiología , Displasia Septo-Óptica/patología
6.
J Clin Endocrinol Metab ; 91(3): 968-72, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16403814

RESUMEN

CONTEXT: Several studies found links between DNA methylation and gene expression. In patients with idiopathic hirsutism, a preferential methylation of the of shorter androgen receptor (AR) alleles was hypothesized to be responsible for the abnormal hair growth. OBJECTIVE: The objective of this study was to assess whether abnormalities in the AR function in both peripheral blood leukocytes (PBLs) and androgen target tissues are present in children with premature pubarche (PP). DESIGN: Human DNA was extracted from PBLs and pubic hair and CAG repeats length and methylation status of the AR gene were analyzed. SETTING: The study was performed at a Pediatric Endocrinology referral clinic. PATIENTS: Twenty-five girls with PP, 23 prepubertal children, and 10 girls with Tanner stage II pubertal development were studied. MAIN OUTCOME MEASURE: The main outcome measures were CAG repeat length and AR methylation pattern in PBLs and pubic hair. RESULTS: In PBLs from PP patients, AR gene methylation was significantly lower (P < 0.01) than that of prepubertal children and similar to that of girls with Tanner II stage pubertal development. A negative correlation between AR gene methylation in PBLs and the age of normal children was detected. PATIENTS with PP exhibited a hair follicle AR methylation pattern similar to that of Tanner stage II girls. The mean number of CAG repeats was lower in PP patients than in prepubertal and Tanner stage II girls, although it was within the normal range for the general population in both groups. CONCLUSIONS: The increased AR gene activity observed in PP patients, as indicated by the reduced AR gene methylation pattern, together with the presence of shorter CAG repeats, might lead to hypersensitivity of the hair follicles to steroid hormones and therefore to the premature development of pubic hair.


Asunto(s)
Metilación de ADN , Pubertad Precoz/genética , Receptores Androgénicos/genética , Niño , Femenino , Folículo Piloso/fisiopatología , Humanos , Reacción en Cadena de la Polimerasa , Valores de Referencia , Repeticiones de Trinucleótidos
7.
Eur J Endocrinol ; 154(3): 425-31, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16498056

RESUMEN

OBJECTIVE: Aromatase, the key enzyme involved in estrogen synthesis, is expressed in a variety of cells and tissues including human peripheral blood leukocytes (PBLs). The present study was designed to evaluate PBL aromatase gene expression in male and female subjects of different age groups. In addition, differences in gene expression during the follicular and luteal phase of the menstrual cycle in women, and before and after testosterone administration in men, were estimated. DESIGN: Aromatase mRNA and protein were measured in PBLs obtained from young (n = 10) and postmenopausal women (n = 10), men (n = 15), and prepubertal children (n = 10). Aromatase mRNA and protein were also measured during the follicular and luteal phases of the menstrual cycle in women, and before and after the intramuscular administration of 250 mg testosterone enanthate in men. METHODS AND RESULTS: Aromatase mRNA measured by real-time PCR in PBLs from women during the follicular phase was significantly higher than during the luteal phase of the menstrual cycle (P < 0.05). In men, PBL aromatase mRNA values increased significantly following testosterone administration (P < 0.05). PBL mRNA aromatase levels in women during the follicular phase and men after testosterone administration were significantly higher (one-way ANOVA; P < 0.05) than in any other group. Children, postmenopausal women, and women during the luteal phase showed the lowest aromatase mRNA expression. The results of the immunoblot analysis confirmed the data obtained by real-time PCR. A positive correlation between PBL aromatase mRNA values and plasma estradiol and estrone levels during the follicular phase of the menstrual cycle was observed in the group of adult women. No other correlations were found. CONCLUSIONS: The aromatase gene is differentially expressed in PBLs from women, men, and prepubertal children, indicating a sexual dimorphism in the enzyme expression and an important role of sex steroids in the modulation of aromatase gene expression.


Asunto(s)
Envejecimiento/metabolismo , Aromatasa/sangre , Leucocitos/enzimología , Adulto , Aromatasa/biosíntesis , Western Blotting , Separación Celular , Niño , ADN/biosíntesis , ADN/genética , Estradiol/sangre , Estrona/sangre , Femenino , Fase Folicular/metabolismo , Humanos , Fase Luteínica/metabolismo , Masculino , Ciclo Menstrual/metabolismo , Progesterona/sangre , ARN/biosíntesis , ARN/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Caracteres Sexuales , Testosterona/sangre
9.
Transplant Proc ; 47(7): 2223-6, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26361684

RESUMEN

We report a case of primary renal allograft dysfunction and early acute cell-mediated rejection after a 12/12 HLA antigen zero-mismatch (0MM) transplant. The recipient was a 40-year-old white man who was highly allosensitized, with a calculated panel reactive antibody score of 100%. In posteroperative day 1 the recipient remained anuric and underwent dialysis because of hyperkalemia. Graft biopsy showed early acute cellular rejection, Banff grade 2B. No evidence of antibody-mediated rejection was observed. To our knowledge, this case is the 1st to report early cell-mediated rejection after 12/12 HLA antigen 0MM kidney transplantation. This case suggests that highly sensitized candidates are at high immunologic risk even in the context of 0MM kidney transplantation.


Asunto(s)
Glomerulonefritis por IGA/cirugía , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Fallo Renal Crónico/cirugía , Disfunción Primaria del Injerto/diagnóstico , Adulto , Biopsia , Citometría de Flujo , Glomerulonefritis por IGA/inmunología , Prueba de Histocompatibilidad , Humanos , Fallo Renal Crónico/inmunología , Trasplante de Riñón , Masculino , Disfunción Primaria del Injerto/terapia , Trasplante Homólogo , Resultado del Tratamiento
10.
Endocrinology ; 138(11): 4806-11, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9348209

RESUMEN

The presence of immunoreactive CRH was recently demonstrated in human ovaries. CRH immunoreactivity was localized by immunohistochemistry in the cytoplasm of thecal cells surrounding the ovarian follicles, in luteinized cells of the stroma, and in large granulosa-derived luteinized cells of developing corpora lutea. Also, CRH and its receptors were identified in Leydig cells of the testis where CRH was shown to inhibit testosterone biosynthesis. To examine the role of CRH in the ovary, we studied its effect on estradiol (E2) and progesterone (P4) release by human granulosa cells obtained from women undergoing in vitro fertilization for male factor infertility or uni- or bilateral tubal impatency. In all subjects, superovulation was induced by treatment with gonadotropins. The effects of graded doses of ovine CRH (10[-11]-10[-6] mol/liter) were evaluated in the conditioned medium obtained after 24 h incubation of the cells. All CRH concentrations employed except for the lowest one (10[-11] mol/liter) caused a significant decrease of media E2 and P4 levels. Maximal inhibition for both E2 and P4 production was obtained by 10[-6] mol/liter CRH concentration, which decreased hormone production by 39% and 34%, respectively. The alpha-helical CRH9-41 antagonist at 10(-6) and 10(-7) mol/liter blocked the suppressive effect of 10(-9) mol/liter CRH on both E2 and P4 secretion, while it had no effect when added to the culture media without CRH. Since interleukin (IL-1)-1 mediates certain actions of CRH on leukocytes, we examined whether the CRH effect on ovarian steroidogenesis was IL-1-mediated. Interleukin-1 receptor antagonist at 10(-7) and 10(-6) mol/liter blocked the inhibitory effects of CRH on E2 and P4 secretion, while it had no effect in the absence of CRH. In conclusion, CRH exerts a CRH- and IL-1 receptor-mediated inhibitory effect on ovarian steroidogenesis and might be actively involved in the still enigmatic processes of follicular atresia and luteolysis.


Asunto(s)
Hormona Liberadora de Corticotropina/farmacología , Estradiol/biosíntesis , Antagonistas de Estrógenos/farmacología , Células de la Granulosa/metabolismo , Células Lúteas/metabolismo , Progesterona/antagonistas & inhibidores , Receptores de Interleucina-1/fisiología , Adulto , Células Cultivadas , Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Medios de Cultivo/metabolismo , Femenino , Líquido Folicular/metabolismo , Humanos , Progesterona/biosíntesis , Receptores de Interleucina-1/antagonistas & inhibidores
11.
J Clin Endocrinol Metab ; 81(4): 1397-400, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8636340

RESUMEN

Previous studies have shown that CRH is capable of inhibiting GH release in response to GHRH in adult subjects, and this effect appeared to be sex dependent and more pronounced in women than in men. To assess whether CRH has an inhibitory action on GH release in children also, the effects of graded doses of CRH on the GHRH-induced GH secretion were studied in three groups of prepubertal children. All subjects underwent a GHRH test (1 microgram/kg), followed, on separate occasions, by the combined administration of GHRH (1 microgram/kg) and CRH (1 microgram/kg, group A, n = 6; 1.5 microgram/kg, group B, n = 6; 2 microgram/kg, group C, n = 7). GH concentrations in response to the single GHRH injection were comparable in the three groups. The combined administration of GHRH and CRH resulted in serum GH concentrations similar to those obtained in the same subjects in response to GHRH alone when 1 and 1.5 microgram/kg CRH were given. In contrast, the administration of 2 microgram/kg CRH together with GHRH led to an increase in GH concentrations significantly lower than those after the GHRH injection alone (GH area under the curve, 1022.18 +/- 106.26 vs. 3109.16 +/- 794.29 microgram/Lx24 h; P < 0.05). No differences in the GH response to GHRH alone or to GHRH plus CRH were detected between male and female subjects. The results of the present study indicate that CRH is capable of inhibiting GHRH-induced GH release in children. Moreover, the inhibitory effect by CRH appears to be dose dependent and not sex related.


Asunto(s)
Hormona Liberadora de Corticotropina , Hormona Liberadora de Hormona del Crecimiento , Hormona del Crecimiento/metabolismo , Adolescente , Hormona Adrenocorticotrópica/sangre , Adulto , Análisis de Varianza , Niño , Femenino , Hormona del Crecimiento/sangre , Hormona Liberadora de Hormona del Crecimiento/antagonistas & inhibidores , Humanos , Hidrocortisona/sangre , Cinética , Masculino , Pubertad , Radioinmunoensayo , Juego de Reactivos para Diagnóstico , Caracteres Sexuales , Factores de Tiempo
12.
J Clin Endocrinol Metab ; 81(2): 482-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8636254

RESUMEN

Both exogenous and endogenous hypercortisolism result in reduced GH secretion and decreased somatic growth. However, little is known about the relation between endogenous cortisol and GH secretion under physiological or slightly disturbed conditions. To examine this, we measured and evaluated the pulsatility and circadian rhythmicity, and we cross-correlated the secretory patterns of cortisol and GH in six prepubertal patients with nonclassic 21-hydroxylase deficiency (NCCAH) and seven age-matched short-normal children. Cortisol and GH were secreted in a pulsatile fashion in both the NCCAH and control groups. The nocturnal peak cortisol increment and time-integrated area were lower in the NCCAH patients than in controls, whereas there was no difference in the total 24-h cortisol secretion between the two groups. The nocturnal increase of GH in NCCAH children, on the other hand, was associated with a significant augmentation of the pulse amplitude, whereas in control children there was an elevation of the baseline component. The cross-correlation analysis of the 24-h raw data showed that cortisol and GH were negatively correlated at brief lag times of 0-30 min, and positively correlated at long lag times of 12-12.5 h in both groups, with cortisol leading GH. The negative correlation might reflect either the negative effect of glucocorticoids on the adrenergic system, which stimulates GH secretion through GH-releasing hormone (GHRH) elevations and somatostatin (SRIH) decreases, or the absence of an inhibitory effect of CRH on SRIH. The positive correlation may reflect the positive effect of glucocorticoids on the GH gene. In conclusion, NCCAH children have a mild nocturnal cortisol deficiency compared with control children, as previously reported, and a distinct circadian pattern of pulsatile GH secretion. The hypothalamic-pituitary-adrenal (HPA) axis exerts both negative and positive influences on GH secretion, with mild disturbances in cortisol biosynthesis associated with slight alterations of GH secretion.


Asunto(s)
Hiperplasia Suprarrenal Congénita , Hormona del Crecimiento/metabolismo , Hidrocortisona/metabolismo , Niño , Ritmo Circadiano , Femenino , Humanos , Masculino , Periodicidad , Análisis de Regresión
13.
J Clin Endocrinol Metab ; 86(5): 2065-72, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11344208

RESUMEN

Thyroid hormones and leptin have effects on similar aspects of body homeostasis, such as energy expenditure, thermogenesis, and metabolic efficiency. Thus, the cross-talk between the thyrostat and the lipostat might play a crucial role in the maintenance of body homeostasis. To investigate the relationship between the hypothalamic-pituitary-thyroid (HPT) axis and leptin under physiological conditions, we evaluated the pulsatility and circadian rhythmicity and time-cross-correlated the 24-h secretory patterns of leptin and TSH in 12 short normal prepubertal children (6 girls and 6 boys). In both male and female subjects, leptin was secreted in a pulsatile and circadian fashion, with a nocturnal leptin surge that was more pronounced in males than in females. Mean 24-h leptin levels and total area under the curve were significantly higher in girls than in boys. This was mainly due to the nighttime mean leptin levels and total area under the curve, which were higher than those in boys. The cross-correlated 24-h leptin and TSH levels revealed significant positive and negative correlations. The positive one, of leptin over TSH, suggests a positive feedback regulation by leptin on the HPT axis, which might play an important role in triggering the neuroendocrine response to starvation, including decreased thyroid hormone levels. The negative correlation, of TSH over leptin, could explain the compensatory changes in adipocyte metabolism, and indirectly in circulating leptin levels, in response to alterations in thyroid status. In conclusion, we suggest that under baseline physiological conditions, the HPT axis has a prevailing inhibitory effect on leptin secretion, whereas leptin has a prevailing positive effect on the HPT axis. The sexual dimorphism in leptin levels does not seem to influence in a major way the interactions between the HPT axis and leptin.


Asunto(s)
Leptina/metabolismo , Tirotropina/metabolismo , Estatura , Niño , Ritmo Circadiano , Femenino , Humanos , Sistema Hipotálamo-Hipofisario/fisiología , Masculino , Sistema Hipófiso-Suprarrenal/fisiología , Análisis de Regresión , Caracteres Sexuales , Hormonas Tiroideas/sangre
14.
J Clin Endocrinol Metab ; 86(8): 3729-34, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502803

RESUMEN

The hormonal regulation of the ob gene and leptin secretion in humans is still unclear. To investigate the interactions among leptin, cortisol, and GH, we analyzed and time-cross-correlated their spontaneous 24-h secretion in 12 short normal prepubertal children of both sexes (6 females and 6 males). Time-cross-correlation analyses demonstrated that leptin and cortisol were correlated in both a negative and positive fashion. The negative correlation, with cortisol leading leptin by 4 and 3 h for boys and girls, respectively, might reflect the stimulatory effect of CRH on the sympathetic system, which inhibits leptin secretion; the positive correlation, with leptin leading cortisol by 6 and 5 h for boys and girls, respectively, might reflect a direct effect of leptin on CRH secretion in the hypophyseal portal system. Time-cross-correlation analyses also showed a strong positive correlation between GH and leptin concentrations, with GH leading leptin by 5 and 2 h for boys and girls, respectively, suggesting a possible direct leptin-releasing effect of GH on adipocytes. We conclude that cross-correlation analyses of 24-h hormone secretions under baseline physiological conditions suggest that the hypothalamic-pituitary-adrenal axis might have a prevailing inhibitory effect on leptin secretion, whereas leptin might exert a positive effect on the hypothalamic-pituitary-adrenal axis. The relation between GH and leptin could be a direct one and characterized prevalently by a positive effect of GH on leptin secretion. Further investigations using different experimental systems are needed to ascertain the validity of these mathematically educed conclusions.


Asunto(s)
Estatura , Ritmo Circadiano/fisiología , Hormona de Crecimiento Humana/metabolismo , Hidrocortisona/metabolismo , Leptina/metabolismo , Niño , Hormona Liberadora de Corticotropina/fisiología , Femenino , Hormona de Crecimiento Humana/sangre , Humanos , Hidrocortisona/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Leptina/sangre , Masculino , Modelos Biológicos , Pubertad , Valores de Referencia , Factores Sexuales
15.
J Clin Endocrinol Metab ; 84(3): 1091-5, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10084600

RESUMEN

Idiopathic hirsutism may result from an increase in the androgen receptor (AR)-mediated sensitivity of the hair follicle. The AR gene is located on the X-chromosome and contains a highly polymorphic trinucleotide repeat (CAGn) in its first exon, whose length and methylation pattern affect both AR expression and function. We analyzed these CAG repeats in the genomic DNA from 16 nonhyperandrogenic hirsute patients (Ferriman score: 16 +/- 4.7, mean +/- SD) and 10 normal controls (Ferriman score: 3 +/- 1.4), who were similar in their hormonal profiles. We found no difference in the number of CAG repeats between hirsute patients and controls, and no correlation between number of repeats and the Ferriman score or hormonal values. However, after DNA digestion with methylation-sensitive HpaII and measurement of the optical density, we found a marked decrease in the hirsute group (P < 0.0001), which was greater than in the control group (P = 0.0003). In addition, in the hirsute patients, the shorter of the two alleles was preferentially less methylated (P = 0.007), suggesting skewing of X-chromosome inactivation in the patients but not in the controls. When the mean optical density of both alleles was correlated with the Ferriman score, we observed a significant negative correlation (P = 0.02, r = -0.45), which became stronger when the shorter alleles were analyzed separately (P = 0.01; r = 0.48). We conclude that nonhyperandrogenic hirsutism is associated with skewing of X-chromosome inactivation in peripheral blood lymphocytes. This leads to the longer of the two AR alleles being preferentially methylated, allowing for the shorter (and presumably, more functional) allele to be expressed on the active X-chromosome. Further studies need to be performed to investigate whether this phenomenon is present in androgen-sensitive tissues in these patients.


Asunto(s)
Andrógenos/fisiología , Hirsutismo/genética , Hirsutismo/fisiopatología , Receptores Androgénicos/fisiología , Cromosoma X/fisiología , Adulto , Andrógenos/sangre , Secuencia de Bases/genética , Resistencia a Medicamentos , Femenino , Hirsutismo/sangre , Humanos , Repeticiones de Microsatélite/genética
16.
J Clin Endocrinol Metab ; 81(2): 601-6, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8636275

RESUMEN

To assess whether patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency exhibit a steroidogenic response to GnRH agonist consistent with functional ovarian hyperandrogenism (FOH) and elucidate the relationship between adrenal and ovarian hyperandrogenism, the LH, FSH, estradiol, 17-hydroxyprogesterone (17-OHP), androstenedione, total testosterone, dehydroepiandrosterone, and 17-hydroxypregnenolone responses to a sc dose of leuprolide acetate (500 micrograms) were evaluated in 10 patients with classic CAH (mean age, 18.4 +/- 0.95 yr), 7 of whom had oligomenorrhea, pretreated with dexamethasone (2 mg/day for 5 days, including the day of the test). The results were compared with those obtained in 11 patients with FOH (mean age, 18.7 +/- 0.46 yr) and 17 normal women (mean age, 19.68 +/- 0.59 yr) not pretreated with dexamethasone. Leuprolide acetate stimulation caused a significant augmentation of plasma E2, 17-OHP, androstenedione, testosterone, and 17-hydroxypregnenolone concentrations in all CAH patients. However, in only 6 (60%) of them, all with oligomenorrhea, was the 17-OHP response (posttest minus pretest value) similar to that of FOH patients and significantly higher than that in controls. In this subset of CAH patients, LH plasma levels after stimulation were significantly higher than those of CAH subjects with 17-OHP responses in the normal range, controls, and FOH patients, whereas FSH levels were similar to those of controls. In this latter group, plasma FSH concentrations after stimulation were significantly higher than those in FOH. In conclusion, the results of the present study indicate that LH-dependent functional ovarian hyperandrogenism is frequent in patients with classic CAH. As ovarian hyperandrogenism might be partially responsible for the menstrual irregularities that are common complications in such patients, all classic CAH patients with oligomenorrhea should undergo short term stimulation with GnRH agonists to ascertain the presence of ovarian hyperandrogenism and receive appropriate treatment.


Asunto(s)
Hiperplasia Suprarrenal Congénita , Hiperplasia Suprarrenal Congénita/fisiopatología , Leuprolida , Ovario/fisiopatología , Hipófisis/fisiopatología , 17-alfa-Hidroxipregnenolona/sangre , 17-alfa-Hidroxiprogesterona , Adolescente , Hiperplasia Suprarrenal Congénita/enzimología , Adulto , Androstenodiona/sangre , Deshidroepiandrosterona/sangre , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hidroxiprogesteronas/sangre , Cinética , Hormona Luteinizante/sangre , Testosterona/sangre
17.
J Clin Endocrinol Metab ; 82(11): 3677-83, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9360525

RESUMEN

Both exogenous and endogenous hypercortisolism result in reduced TSH secretion and mild hypothyroidism. However, little is known about the relation between endogenous TSH and cortisol secretion under physiological or slightly disturbed conditions. To examine this, we evaluated the pulsatility and circadian rhythmicity and time-cross-correlated the 24-h secretory patterns of cortisol and TSH in eight prepubertal children with nonclassical congenital adrenal hyperplasia (NCCAH) and eight age-matched short normal children. In both groups, TSH and cortisol were secreted in a pulsatile and circadian fashion, with a clear nocturnal TSH surge. Although no difference in mean 24-h TSH levels was observed between the two groups, daytime TSH levels were lower in the NCCAH group than in control children (P < 0.05). The cross-correlation analysis of the 24-h raw data showed that TSH and cortisol were negatively correlated, with a 2.5-h lag time for both groups, with cortisol leading TSH. This correlation might reflect a negative glucocorticoid effect exerted on the hypothalamic-pituitary-thyroid axis under physiological conditions. A significant positive correlation with TSH leading cortisol was observed at 8.5 and 5.5 h lag times for the control and NCCAH groups, respectively. The substantially shorter lag time of this positive correlation in NCCAH children than in controls suggests that in the latter, the nocturnal TSH peak occurs temporally closer to their compromised morning cortisol peak. These data indicate that the hypothalamic-pituitary-adrenal axis has a primarily negative influence on endogenous TSH secretion and that even mild disturbances in cortisol biosynthesis are associated with slight alterations in TSH secretion.


Asunto(s)
Hiperplasia Suprarrenal Congénita/fisiopatología , Ritmo Circadiano , Hidrocortisona/metabolismo , Periodicidad , Tirotropina/metabolismo , Estatura , Niño , Femenino , Humanos , Masculino
18.
J Clin Endocrinol Metab ; 83(4): 1348-57, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9543166

RESUMEN

Increased extraglandular aromatization has been reported as the cause of familial gynecomastia. We studied a kindred with aromatase excess inherited in an autosomal dominant manner, in which affected males had heterosexual precocity and/or gynecomastia, and affected females had isosexual precocity and/or macromastia. The propositus was a 9-yr-old boy with gynecomastia. His 7.5-yr-old sister had precocious puberty, and their father and paternal grandmother had peripubertal gynecomastia and macromastia, respectively. Serum concentrations of gonadal and adrenal steroid hormones were determined before and after the administration of corticotropin and/or hCG. Aromatase activity was determined by [3H]delta4-androstenedione to [3H]estrone conversion by cultured skin fibroblasts and/or Epstein-Barr virus-transformed lymphocytes and was detected by immunohistochemistry and/or Western analysis. Linkage was examined with a polymorphism of the aromatase (P450arom) gene. The P450arom messenger ribonucleic acid was analyzed by rapid amplification of complementary DNA (cDNA) ends, ribonuclease protection assay, and RT-PCR. hCG testing demonstrated a high rate of conversion of delta4-androstenedione to estrone and of testosterone to estradiol in the propositus and his father. Treatment of the propositus and his sister was initiated with an aromatase inhibitor (testolactone) and a GnRH analog, which successfully delayed skeletal and pubertal development in both children. Markedly increased aromatase activity was found in the patients' fibroblasts and Epstein-Barr virus-transformed lymphocytes. The P450arom polymorphism segregated with the disease in the family. A new 5'-splice variant was present in the patients' P450arom messenger ribonucleic acid, thus identifying yet another first exon of this gene, which appears to be aberrantly expressed in this family. In conclusion, a family with the aromatase excess syndrome is described, in which the condition was inherited in an autosomal dominant manner, led to feminizing manifestations in both sexes, and was associated with the aberrant utilization of a novel transcript of the P450arom gene.


Asunto(s)
Aromatasa/metabolismo , Feminización/genética , Genes Dominantes , Ginecomastia/genética , Transcripción Genética , Adulto , Secuencia de Bases , Western Blotting , Línea Celular , Niño , Exones , Femenino , Ligamiento Genético , Humanos , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Linaje , Síndrome
19.
J Steroid Biochem Mol Biol ; 64(5-6): 245-50, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9618025

RESUMEN

The human aromatase gene (P450arom) is widely expressed, albeit in a tissue-specific manner. In the present study, we measured aromatase activity and investigated the transcribed and translated products of the P450arom gene before and after Epstein-Barr virus (EBV) transformation in peripheral blood lymphocytes (PBLs) from normal individuals. Aromatase activity was determined by [3H]-delta4-androstenedione (A) to [3H]-estrone (E1) conversion. Cellular total RNA and protein lysates were subjected to RT-PCR and Western analysis, respectively. Rapid amplification of cDNA ends (RACE) was used for the detection of novel 5'-untranslated ends of the P450arom mRNA, which were subsequently sequenced and compared to the known transcripts of this gene. In untransformed PBLs, two known variants of exon 1 of the P450arom gene were expressed, corresponding to promoters PI.3 and PII, or 1c and 1d, respectively. In EBV-transformed PBLs, a cryptic splice site was revealed and a new 5'-untranslated product was found. RNase protection assay confirmed that this splice variant is not a RACE artifact. The 53 K P450arom protein was detectable in PBLs both before and after EBV transformation. We conclude that (i) the P450arom mRNA is present in human PBLs and (ii) EBV transformation of the latter leads to novel alternative splicing of the 5' end of this gene.


Asunto(s)
Empalme Alternativo/genética , Aromatasa/genética , Exones/genética , Regulación Enzimológica de la Expresión Génica/genética , Linfocitos/fisiología , Androstenodiona/metabolismo , Secuencia de Bases , Clonación Molecular , Femenino , Herpesvirus Humano 4/genética , Humanos , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas/genética , ARN Mensajero/análisis , Ribonucleasas/metabolismo , Análisis de Secuencia de ADN , Transformación Genética/genética
20.
Metabolism ; 47(11): 1419-22, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9826224

RESUMEN

Intravenous infusion of corticotropin 1-24 (ACTH 1-24) followed by a plasma cortisol measurement after 60 minutes of less than 20 microg/dL indicates clinically important glucocorticoid deficiency. In this study, we evaluated the morning plasma cortisol response to an intramuscular (IM) injection of ACTH 1-24 (250 microg) in 64 healthy men. Plasma cortisol increased significantly 30 and 60 minutes after IM ACTH 1-24 (P < .0001). In most subjects, a maximal response was obtained at 60 minutes. The cortisol response correlated positively with the morning basal cortisol concentration. The lowest cortisol peak and the lowest increment observed after IM ACTH 1-24 were, respectively, 12.6 and 3.5 microg/dL after 30 minutes and 16.3 and 5.3 microg/dL after 60 minutes. We conclude that a plasma cortisol level less than 16.0 microg/dL 60 minutes after IM ACTH 1-24 can be used as an index of glucocorticoid deficiency.


Asunto(s)
Cosintropina/farmacología , Hidrocortisona/sangre , Adulto , Cosintropina/administración & dosificación , Humanos , Inyecciones Intramusculares , Masculino , Valores de Referencia
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