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1.
J Endocrinol Invest ; 45(9): 1653-1662, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35460461

RESUMO

PURPOSE: The main purpose of this study was to investigate the effects of 12 months of rhPTH (1-84) (Natpar®) treatment in a cohort of patients selected according to the indications of hypoparathyroidism guidelines. The use of recombinant human PTH (1-84) [rhPTH (1-84)] is approved as hormonal replacement therapy in patients with hypoparathyroidism not adequately controlled with conventional therapy. METHODS: It is a multicenter, observational, retro-prospective, open label study. Eleven Italian Endocrinological centers, members of Hypoparathyroidism Working Group of the Italian Society of Endocrinology (HypoparaNET) were involved. Main outcome measures were serum and urinary calcium and phosphate concentration, calcium-phosphate product, renal function, oral calcium and vitamin D doses, and clinical manifestations. RESULTS: Fourteen adult subjects, affected by chronic hypoparathyroidism, were treated with rhPTH (1-84) for 12 months. At 12 months of rhPTH (1-84) treatment, 61.5% of patients discontinued calcium supplement and 69.2% calcitriol. Mean albumin-adjusted total serum calcium levels quickly normalized after initiation of rhPTH (1-84) treatment compared to baseline (p = 0.009), remaining in the normal range until 12 months. Rare hypo-hypercalcemia episodes were reported. Renal function was maintained normal and no renal complications were reported. Serum and urinary phosphate and urinary calcium were maintained in the normal range. Mean phosphatemia levels linearly decreased from 3 months up to 12 months compared to baseline (p = 0.014). No severe adverse events were described. CONCLUSIONS: Biochemical and clinical results confirm the efficacy and safety of rhPTH (1-84) therapy, which represents an important option for hypoparathyroid patients unresponsive to conventional therapy.


Assuntos
Cálcio , Hipoparatireoidismo , Adulto , Humanos , Hormônio Paratireóideo , Fosfatos/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento
2.
J Endocrinol Invest ; 44(10): 2219-2226, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33666875

RESUMO

PURPOSE: Genotype-phenotype correlation in congenital 21 hydroxylase deficiency is strong but by no means absolute. Indeed, clinical and hormonal features may vary among patients carrying similar CYP21A2 mutations, suggesting that modifier genes may contribute to the phenotype. Aim of the present study was to evaluate whether polymorphisms in the p450  oxidoreductase (POR) gene may affect clinical features in patients with 21 hydroxylase deficiency METHODS: Sequencing of the POR gene was performed in 96 patients with 21 hydroxylase deficiency (49 classic, 47 non-classic) and 43 control subjects. RESULTS: Prevalence of POR polymorphisms in patients with 21 hydroxylase was comparable to controls and known databases. The rs2228104 polymorphism was more frequently associated with non-classic vs classic 21 hydroxylase deficiency (allelic risk 7.09; 95% C.I. 1.4-29.5, p < 0.05). Classic 21 hydroxylase-deficient carriers of the minor allele in the rs2286822/rs2286823 haplotype presented more frequently the salt-wasting form (allelic risk 1.375; 95% C.I. 1.138-1.137), more severe Prader stage at birth (allelic risk 3.85; 95% C.I. 3.78-3.92), higher ACTH levels, and younger age at diagnosis. CONCLUSIONS: Polymorphisms in the POR gene are associated with clinical features of 21 hydroxylase deficiency both as regards predisposition to classic vs non-classic forms and severity of classic adrenal hyperplasia.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Hiperplasia Suprarrenal Congênita/patologia , Sistema Enzimático do Citocromo P-450/genética , Estudos de Associação Genética , Polimorfismo Genético , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Adulto Jovem
4.
Horm Metab Res ; 46(7): 515-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24799024

RESUMO

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.


Assuntos
Hiperplasia Suprarrenal Congênita/enzimologia , Hiperplasia Suprarrenal Congênita/genética , Mutação/genética , Esteroide 21-Hidroxilase/química , Esteroide 21-Hidroxilase/genética , Sequência de Aminoácidos , Animais , Western Blotting , Células COS , Criança , Chlorocebus aethiops , Feminino , Genótipo , Humanos , Recém-Nascido , Itália , Masculino , Dados de Sequência Molecular , Proteínas Mutantes/metabolismo , Fenótipo , Estrutura Secundária de Proteína , Alinhamento de Sequência
5.
J Endocrinol Invest ; 35(10): 877-81, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22104652

RESUMO

UNLABELLED: Autoimmune polyendocrinopathy-candidiasis-ectodermal- dystrophy (APECED), also known as autoimmune polyendocrine syndrome type 1 (APS-1), is a very rare disease. Diagnosis requires the presence of at least two of three major clinical features: chronic mucocutaneous candidiasis, chronic hypoparathyroidism, and Addison's disease. DESIGN: In this study, we analyzed Autoimmune Regulator (AIRE) gene mutations and genotype-phenotype correlation in APECED patients originating from Calabria, a region in the south of Italy. PATIENTS AND METHODS: Four patients and their first-degree relatives were evaluated for clinical manifestations, autoantibody presence and AIRE gene mutations. RESULTS: Three patients carried a homozygous W78R mutation on exon 2, typical of patients with APECED from Apulia; the fourth patient had a homozygous R203X mutation on exon 5, typical of APECED patients from Sicily. Clinical disease expression showed wide variability. Analysis of relatives allowed the identification of 6 heterozygotes, none of whom showed major findings of APECED. CONCLUSIONS: No AIRE gene mutations specific to Calabria were found in patients with APS-1, but mutations similar to those in patients from Apulia and Sicily. Heterozygosity for AIRE gene mutation is not associated with major findings of APECED.


Assuntos
Autoanticorpos/sangue , Mutação/genética , Poliendocrinopatias Autoimunes/genética , Poliendocrinopatias Autoimunes/imunologia , Fatores de Transcrição/genética , Adolescente , Adulto , Autoanticorpos/imunologia , Criança , Feminino , Estudos de Associação Genética , Heterozigoto , Homozigoto , Humanos , Itália/epidemiologia , Masculino , Poliendocrinopatias Autoimunes/epidemiologia , Prognóstico , Sicília , Adulto Jovem , Proteína AIRE
6.
J Endocrinol Invest ; 34(4): 292-5, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20543555

RESUMO

BACKGROUND: GH-IGF-I axis is mainly involved in the complex process of somatic growth but emerging evidence suggests that it also influences hypothalamic-pituitary-gonadal (HPG) function. SUBJECTS: We report some data regarding long-term auxological and pubertal outcome of five female patients with hereditary forms of GH-IGF-I deficiency (Laron and GH-gene deletion syndrome) and a mean age of 23.4±5.3 yr (range 19-32). METHODS: All the patients received recombinant human IGF-I (rhIGF-I, Pharmacia and Upjohn, Stockholm, Sweden, and rhIGF-I, Genentech, San Francisco, CA, USA) from a mean age of 8.6 yr (range 3.2-14.2) up to the final height. RESULTS: Final height was very disappointing (≤ -5.0 SD scores) and lower than target height in all the patients. Pubertal onset was delayed in most of them but menarche occurred spontaneously in all the patients. Median age at menarche was 15.1 yr. Menstrual cycles were regular for several years. Median duration of gynecological follow- up was 8.3 yr with the longest span of 17.2 yr. CONCLUSION: We can assert that GH-IGF-I axis has an essential role in promoting linear growth in humans and its physiological action cannot be replaced by pharmacological treatment in most patients with hereditary forms of IGF-I insufficiency as demonstrated by their subnormal final height. Our clinical observations can also support an essential role of IGF-I in genitalia growth but not in the function of HPG axis as demonstrated by the maintenance of regular menstrual cycles in the presence of subnormal levels of IGF-I after treatment discontinuation.


Assuntos
Hormônio do Crescimento Humano/genética , Fator de Crescimento Insulin-Like I/deficiência , Fator de Crescimento Insulin-Like I/uso terapêutico , Síndrome de Laron/fisiopatologia , Puberdade/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Síndrome de Laron/genética , Ciclo Menstrual/fisiologia , Proteínas Recombinantes/uso terapêutico , Adulto Jovem
7.
J Endocrinol Invest ; 30(2): 97-103, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17392598

RESUMO

Pseudohypoparathyroidism type Ia (PHP-Ia) is characterized by Albright's hereditary osteodistrophy (AHO) and resistance to hormones that act via the alpha subunit of the Gs protein (Gsalpha) protein, ie PTH, TSH, FSH/LH, and, as recently described in limited series, GHRH. However, the current lack of data on GHRH secretion, obesity and short stature included in the AHO phenotype hampers interpretation of GH secretory status and its effects on these subjects. We evaluated GH secretion after GHRH plus arginine (Arg) stimulus, IGF-I levels and anthropometric features in an exclusively pediatric population of 10 PHP-Ia subjects. Of our PHP-Ia children, 5 out of 10 (50%) showed impaired GH responsiveness to the provocative test, with a lower prevalence than the 75-100% previously reported. A negative correlation (p=0.024) was found between GH secretion and body mass index (BMI), whereas no correlation emerged between GH and IGF-I values (p=0.948). Height and growth velocity did not significantly differ between GH-deficient and GH-sufficient subjects. In the 5 GH-deficient patients, GHRH resistance could arguably be responsible for hormonal impairment; however, 3 of them were obese, showing normal stature and IGF-I levels: the increased BMI in these subjects could influence GH secretion and its effects. In conclusion, GH deficiency is frequent among PHP-Ia children and its prevalence is variable, two factors indicating that GH secretory testing should be part of the routine management of this patient group. It could be argued that GHRH resistance is the pathogenetic mechanism in most patients, but further studies on GHRH secretion are needed to define which values can be considered as raised. Lastly, because BMI has been indicated as a major determinant of evoked adult GH response to provocative testing, GH levels related to increased BMI also in childhood could be helpful in defining GH assessment in obese or overweight PHP-Ia children.


Assuntos
Hormônio do Crescimento Humano/metabolismo , Pseudo-Hipoparatireoidismo/sangue , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Hormônio do Crescimento Humano/sangue , Humanos , Masculino
8.
J Clin Endocrinol Metab ; 91(3): 968-72, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16403814

RESUMO

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.


Assuntos
Metilação de DNA , Puberdade Precoce/genética , Receptores Androgênicos/genética , Criança , Feminino , Folículo Piloso/fisiopatologia , Humanos , Reação em Cadeia da Polimerase , Valores de Referência , Repetições de Trinucleotídeos
9.
Eur J Endocrinol ; 154(3): 425-31, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16498056

RESUMO

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.


Assuntos
Envelhecimento/metabolismo , Aromatase/sangue , Leucócitos/enzimologia , Adulto , Aromatase/biossíntese , Western Blotting , Separação Celular , Criança , DNA/biossíntese , DNA/genética , Estradiol/sangue , Estrona/sangue , Feminino , Fase Folicular/metabolismo , Humanos , Fase Luteal/metabolismo , Masculino , Ciclo Menstrual/metabolismo , Progesterona/sangue , RNA/biossíntese , RNA/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Caracteres Sexuais , Testosterona/sangue
10.
Diabetes Care ; 22(1): 7-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10333896

RESUMO

OBJECTIVE: To shorten the period of carbohydrate intolerance preceding the diagnosis of IDDM in children. RESEARCH DESIGN AND METHODS: The incidence of diabetic ketoacidosis (DKA) was studied in newly diagnosed diabetic children aged 6-14 years, in the area of Parma, Italy, 8 years after an information program on DKA was introduced to teachers, students, parents, and pediatricians. Information was provided by displaying a poster with a few practical messages in 177 primary and secondary public schools. The pediatricians working in the same area were given equipment for the measurement of both glycosuria and blood glucose levels, as well as cards listing guidelines for the early diagnosis of diabetes, to be given to patients. A toll-free number was also provided. Clinical and laboratory features of 24 young diabetic patients diagnosed in the Parma area (group 1) were compared with those of 30 patients coming from two nearby areas in which no campaign for the prevention of DKA had been carried out (group 2). RESULTS: From 1 January 1991 to 31 December 1997, DKA was diagnosed in 3 children from group 1 (12.5%) and in 25 children from group 2 (83.0%) (chi 2 = 26.8; P = 0.0001). The three cases of DKA in group 1 were observed in 1991 (n = 1) and in 1992 (n = 2). No patients from the Parma area who had DKA were admitted to our unit after 1992. The duration of symptoms before diagnosis was 5.0 +/- 6.0 and 28.0 +/- 10.0 days (P < 0.0001), in groups 1 and 2, respectively, Metabolic derangements were less severe in patients of group 1 than in those of group 2. Hospitalization for the treatment of overt diabetes and for the teaching of self-management of the disease lasted 5.4 +/- 1.2 days in group 1 and 13.3 +/- 2.4 days in group 2 (P = 0.002). The total cost of the 8-year campaign was $23,470. CONCLUSIONS: The prevention program for DKA in diabetic children aged 6-14 years, carried out in the Parma area during the last 8 years, was successful. Thanks to this program, cumulative frequency of DKA in new-onset IDDM decreased from 78% during 1987-1991 to 12.5% during 1991-1997. None of the newly diagnosed diabetic children aged 6-14 years and from the Parma area were ever admitted to the hospital for DKA after 1992.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Cetoacidose Diabética/prevenção & controle , Adolescente , Glicemia/análise , Criança , Diabetes Mellitus Tipo 1/urina , Cetoacidose Diabética/epidemiologia , Enurese , Docentes , Glicosúria , Humanos , Estudos Longitudinais , Pais/educação , Educação de Pacientes como Assunto , Prática Privada , Instituições Acadêmicas
11.
Endocrinology ; 138(11): 4806-11, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9348209

RESUMO

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.


Assuntos
Hormônio Liberador da Corticotropina/farmacologia , Estradiol/biossíntese , Antagonistas de Estrogênios/farmacologia , Células da Granulosa/metabolismo , Células Lúteas/metabolismo , Progesterona/antagonistas & inibidores , Receptores de Interleucina-1/fisiologia , Adulto , Células Cultivadas , Hormônio Liberador da Corticotropina/antagonistas & inibidores , Meios de Cultura/metabolismo , Feminino , Líquido Folicular/metabolismo , Humanos , Progesterona/biossíntese , Receptores de Interleucina-1/antagonistas & inibidores
12.
J Clin Endocrinol Metab ; 81(4): 1397-400, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8636340

RESUMO

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.


Assuntos
Hormônio Liberador da Corticotropina , Hormônio Liberador de Hormônio do Crescimento , Hormônio do Crescimento/metabolismo , Adolescente , Hormônio Adrenocorticotrópico/sangue , Adulto , Análise de Variância , Criança , Feminino , Hormônio do Crescimento/sangue , Hormônio Liberador de Hormônio do Crescimento/antagonistas & inibidores , Humanos , Hidrocortisona/sangue , Cinética , Masculino , Puberdade , Radioimunoensaio , Kit de Reagentes para Diagnóstico , Caracteres Sexuais , Fatores de Tempo
13.
J Clin Endocrinol Metab ; 79(4): 1152-7, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7962288

RESUMO

It has been suggested that hypothalamic regulation of GH secretion in children may differ from that in adults. On the other hand, there is evidence that oral glucose administration affects GH secretion through hypothalamic mechanisms. Therefore, we investigated spontaneous and GHRH-stimulated (1 microgram/kg BW) GH responses after oral glucose administration (children, 1.75 g/kg BW; adults, 75 g) in peripubertal normal children (13 girls and 13 boys, aged 11.7 +/- 0.4 yr; range, 8-13) and healthy adults (12 males and 14 females, aged 25.7 +/- 1.2 yr; range, 18-39). Three studies were carried out. In study 1, serum GH levels in 8 children were suppressed (< 1 microgram/L) for 135 min after oral glucose administration. Afterward, there was a rise in serum GH levels. In 8 adults, the suppressive effect of glucose persisted throughout the 210-min study period, and no GH rebound appeared. In study 2, the GH responses to iv GHRH boli in 10 adults and 10 children were, respectively, inhibited, unchanged, or augmented by an oral glucose load administered 30, 60, or 120 min before GHRH challenge. In study 3, oral glucose administration to 8 adults greatly enhanced the GH response to GHRH given 180 min after the glucose, whereas in 8 children, the GH response to GHRH was unchanged. In conclusion, glucose affects basal and GHRH-stimulated GH release in a similar manner in adults and children, indicating that neuroregulatory influences of glucose on the GH axis may not differ in the two age groups. In children, however, the duration of both the initial inhibitory and subsequent stimulatory effects of glucose administration on GH secretion is shorter.


Assuntos
Envelhecimento/metabolismo , Glucose/farmacologia , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Hormônio do Crescimento/metabolismo , Administração Oral , Adolescente , Adulto , Glicemia/análise , Criança , Esquema de Medicação , Feminino , Glucose/administração & dosagem , Hormônio do Crescimento/sangue , Humanos , Masculino
14.
J Clin Endocrinol Metab ; 86(8): 3729-34, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502803

RESUMO

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.


Assuntos
Estatura , Ritmo Circadiano/fisiologia , Hormônio do Crescimento Humano/metabolismo , Hidrocortisona/metabolismo , Leptina/metabolismo , Criança , Hormônio Liberador da Corticotropina/fisiologia , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Fator de Crescimento Insulin-Like I/análise , Leptina/sangue , Masculino , Modelos Biológicos , Puberdade , Valores de Referência , Fatores Sexuais
15.
J Clin Endocrinol Metab ; 69(4): 875-80, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2550509

RESUMO

To determine whether CRH affects adrenal androgen, beta-endorphin (B-E), and ACTH secretion in normal children during sexual maturation, 17-hydroxyprogesterone (17-OHP), androstenedione (D4-A), dehydroepiandrosterone (DHEA), DHEA sulfate (DS), cortisol, B-E, and ACTH were measured after an iv injection of 1 microgram/kg human CRH. Children with premature pubarche were similarly analyzed to establish whether this condition is accompanied by altered hormonal responses to CRH. CRH produced consistent increases in ACTH, B-EP, and cortisol blood levels, which were comparable at all age intervals in all groups. 17-OHP increased after CRH injection, but its response linearly with age. D4-A levels were not influenced, while DHEA and DS levels were only partially influenced by CRH. The stimulated D4-A to 17-OHP ratio increased with sexual maturation, whereas ratios of cortisol to 17-OHP and D4-A to DHEA remained constant. Children with premature pubarche had hormonal responses similar in magnitude to those of prepubertal children of comparable age. In conclusion, an increase in 17,20-desmolase efficiency occurs with postnatal maturation after CRH challenge. Moreover, CRH does not appear to play an important role in premature pubarche.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Androgênios/metabolismo , Hormônio Liberador da Corticotropina , Hidrocortisona/metabolismo , Puberdade Precoce/diagnóstico , beta-Endorfina/metabolismo , 17-alfa-Hidroxiprogesterona , Adolescente , Hormônio Adrenocorticotrópico/sangue , Fatores Etários , Androgênios/sangue , Criança , Pré-Escolar , Feminino , Humanos , Hidrocortisona/sangue , Hidroxiprogesteronas/sangue , Hidroxiprogesteronas/metabolismo , Masculino , Puberdade Precoce/sangue , Valores de Referência , beta-Endorfina/sangue
16.
J Clin Endocrinol Metab ; 86(5): 2065-72, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11344208

RESUMO

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.


Assuntos
Leptina/metabolismo , Tireotropina/metabolismo , Estatura , Criança , Ritmo Circadiano , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Sistema Hipófise-Suprarrenal/fisiologia , Análise de Regressão , Caracteres Sexuais , Hormônios Tireóideos/sangue
17.
J Clin Endocrinol Metab ; 81(2): 482-7, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8636254

RESUMO

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.


Assuntos
Hiperplasia Suprarrenal Congênita , Hormônio do Crescimento/metabolismo , Hidrocortisona/metabolismo , Criança , Ritmo Circadiano , Feminino , Humanos , Masculino , Periodicidade , Análise de Regressão
18.
J Clin Endocrinol Metab ; 84(3): 1091-5, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10084600

RESUMO

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.


Assuntos
Androgênios/fisiologia , Hirsutismo/genética , Hirsutismo/fisiopatologia , Receptores Androgênicos/fisiologia , Cromossomo X/fisiologia , Adulto , Androgênios/sangue , Sequência de Bases/genética , Resistência a Medicamentos , Feminino , Hirsutismo/sangue , Humanos , Repetições de Microssatélites/genética
19.
J Clin Endocrinol Metab ; 74(2): 254-7, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1730803

RESUMO

The natural history of girls with premature pubarche is reported to be normal, but the effects on puberty and on final height are not well documented. We assessed the outcome of a group of girls with premature pubarche from two Latin populations in whom 21-hydroxylase deficiency had been ruled out by an ACTH test. Patients comprised 127 girls (70 Northern-Italian and 57 Northern-Spanish), of whom 69 had entered puberty and 38 had attained adult height. Height, bone age, onset and progression of puberty, height prognosis, adult height, and baseline plasma androgen levels were evaluated. Advanced skeletal maturation and tall stature were constant features during the first years of follow-up and subsequently declined. Puberty began at 9.7 +/- 0.9 yr, and age at menarche (12.0 +/- 1.0 yr) was comparable to maternal and population menarcheal ages. The appearance and chronology of pubertal milestones in both populations were very similar. Adult heights correlated with the height prognosis at diagnosis and at onset of puberty, and were above midparental heights. Premature pubarche produces a transient acceleration in growth and bone maturation with no negative effects on the onset and progression of puberty and final height.


Assuntos
Doenças do Córtex Suprarrenal/fisiopatologia , Hiperfunção Adrenocortical/fisiopatologia , Puberdade , Adolescente , Fatores Etários , Estatura , Criança , Feminino , Humanos , Itália , Menarca , Prognóstico
20.
J Clin Endocrinol Metab ; 82(11): 3677-83, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9360525

RESUMO

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.


Assuntos
Hiperplasia Suprarrenal Congênita/fisiopatologia , Ritmo Circadiano , Hidrocortisona/metabolismo , Periodicidade , Tireotropina/metabolismo , Estatura , Criança , Feminino , Humanos , Masculino
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