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1.
Calcif Tissue Int ; 111(1): 35-46, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35152305

RESUMO

Klinefelter Syndrome (KS) patients, defined by a 47 XXY karyotype, have increased risk of fragility fractures. We have assessed bone microarchitecture by high resolution peripheral quantitative CT (HR-pQCT) at the radius and tibia in young KS patients, naïve from testosterone replacement therapy (TRT). Areal bone mineral density (BMD) and body composition were assessed by dual X-ray absorptiometry (DXA). Total testosterone (tT) was measured at baseline. Bone measurements have been repeated after 30 months of TRT. We enrolled 24 KS patients and 72 age-matched controls. KS patients were (mean ± SD) 23.7 ± 7.8 year-old. KS patients had significantly lower relative appendicular lean mass index (RALM) and lower aBMD at spine and hip than controls. Ten patients (42%) had low tT level (≤ 10.4 nmol/L). At baseline, we observed at radius a marked cortical (Ct) impairment reflected by lower Ct.area, Ct.perimeter, and Ct.vBMD than controls. At tibia, in addition to cortical fragility, we also found significant alterations of trabecular (Tb) compartment with lower trabecular bone volume (BV/TV) and Tb.vBMD as compared to controls. After 30 months of TRT, 18 (75%) KS patients were reassessed. Spine aBMD and RALM significantly increased. At radius, both cortical (Ct.Pm, Ct.Ar, Ct.vBMD, Ct.Th) and trabecular (Tb.vBMD) parameters significantly improved. At tibia, the improvement was found only in the cortical compartment. Young TRT naïve KS patients have inadequate bone microarchitecture at both the radius and tibia, which can improve on TRT.


Assuntos
Densidade Óssea , Rádio (Anatomia) , Absorciometria de Fóton , Adolescente , Adulto , Osso e Ossos , Humanos , Testosterona/uso terapêutico , Tíbia , Adulto Jovem
2.
Mol Hum Reprod ; 27(6)2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-34009290

RESUMO

Male infertility affects about 7% of the general male population. Balanced structural chromosomal rearrangements are observed in 0.4-1.4% of infertile males and are considered as a well-established cause of infertility. However, underlying pathophysiological mechanisms still need to be clarified. A strategy combining standard and high throughput cytogenetic and molecular technologies was applied in order to identify the candidate genes that might be implicated in the spermatogenesis defect in three male carriers of different balanced translocations. Fluorescence in situ hybridization (FISH) and whole-genome paired-end sequencing were used to characterize translocation breakpoints at the molecular level while exome sequencing was performed in order to exclude the presence of any molecular event independent from the chromosomal rearrangement in the patients. All translocation breakpoints were characterized in the three patients. We identified four variants: a position effect on LACTB2 gene in Patient 1, a heterozygous CTDP1 gene disruption in Patient 2, two single-nucleotide variations (SNVs) in DNAH5 gene and a heterozygous 17q12 deletion in Patient 3. The variants identified in this study need further validation to assess their roles in male infertility. This study shows that beside the mechanical effect of structural rearrangement on meiosis, breakpoints could result in additional alterations such as gene disruption or position effect. Moreover, additional SNVs or copy number variations may be fortuitously present and could explain the variable impact of chromosomal rearrangements on spermatogenesis. In conclusion, this study confirms the relevance of combining different cytogenetic and molecular techniques to investigate patients with spermatogenesis disorders and structural rearrangements on genomic scale.


Assuntos
Estudos de Associação Genética/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Infertilidade Masculina/genética , Espermatogênese/genética , Translocação Genética , Adulto , Astenozoospermia/genética , Dineínas do Axonema/genética , Sequência de Bases , Pontos de Quebra do Cromossomo , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Fosfoproteínas Fosfatases/genética , Polimorfismo de Nucleotídeo Único , Sequenciamento do Exoma , Sequenciamento Completo do Genoma , beta-Lactamases/genética
3.
Prog Urol ; 31(8-9): 458-476, 2021.
Artigo em Francês | MEDLINE | ID: mdl-34034926

RESUMO

OBJECTIVES: The Francophone Society of Sexual Medicine (SFMS) and the Andrology and Sexual Medicine Committee (CAMS) of the French Association of Urology (AFU) have brought together a panel of experts to develop French recommendations for the management of testosterone deficiency (TD). METHODS: Systematic review of the literature between 01/2000 and 07/2019. Use of the method of recommendations for clinical practice (RPC) and the AGREE II grid. RESULTS: TD is defined as the association of clinical signs and symptoms suggestive of TD with a decrease in testosterone levels or serum androgen activity. Diagnosis requires a T lower than the reference values in young men on 2 successive assays. Sexual disorders are often at the forefront, and concern the whole male sexual function (desire, arousal, pleasure and orgasm). The most evocative symptoms are: decrease in sexual desire, disappearance of nocturnal erections, fatigue, loss of muscle strength. Overweight, depressed mood, anxiety, irritability and malaise are also frequently found. TD is more common in cases of metabolic, cardiovascular, chronic, andrological diseases, and in cases of corticosteroid, opioid, antipsychotic, anticonvulsant, antiretroviral, or cancer treatment. Since SHBG is frequently abnormal, we recommend that free or bioavailable T is preferred over total T. The treatment of TD requires a prior clinical (DRE, breast examination) and biological (PSA, CBC) assessment. Contraindications to T treatment are: progressive prostate or breast cancer, severe heart failure or recent cardiovascular event, polycytemia, complicated BPH, paternity project. It is possible in cases of sleep apnea syndrome, psychiatric history, stable heart disease, prostate cancer under active surveillance and after one year of complete remission of a low or intermediate risk localized prostate cancer treated in a curative manner. It includes long-term testosterone supplementation and life-style counseling. Treatment is monitored at 3, 6, 12 months and annually thereafter. It is clinical (annual DRE) and biological (total T, PSA, CBC), the most frequent side effect being polyglobulia. CONCLUSION: These recommendations should help improve the management of TD.


Assuntos
Testosterona/deficiência , Testosterona/uso terapêutico , Algoritmos , Árvores de Decisões , Deficiências Nutricionais/diagnóstico , Deficiências Nutricionais/tratamento farmacológico , Humanos , Masculino
4.
Encephale ; 43(5): 423-428, 2017 Oct.
Artigo em Francês | MEDLINE | ID: mdl-27743676

RESUMO

INTRODUCTION: The Klinefelter syndrome (KS) is a genetic condition characterized by an X supernumerary sex chromosome in males. The syndrome is frequently associated with cognitive impairment. Indeed, the different areas of the executive sphere can be affected such as inhibition, cognitive flexibility but also attentional and visual-spatial domain. Social cognition disorders, predominantly on emotional recognition processes, have also been documented. In addition, the syndrome may be associated with psychiatric symptoms. MATERIAL AND METHOD: Our study aims to characterize of the various components of social cognition in the SK: facial emotional recognition, theory of mind and attributional style. For this two groups (SK group versus control group) of participants (n=16) matched for age and sociocultural level were recruited. Participants with intellectual disabilities, psychiatric or neurological disorders were excluded. Three social cognition tests were available: the TREF, the MASC, the AIHQ. Neurocognitive functions were assessed by the fNart, the subtest "logical memory" of the MEM-III, the subtests of the two VOSP battery, the d2, the TMT and the Stroop test. RESULTS: The SK group had specific social cognition disorders in comparison to the control group. Two emotions in particular were less well recognized: fear and contempt. In addition, the SK group had significantly lower results in theory of mind. Regarding the hostile attribution bias, no significant difference was found. Finally, the results showed correlations between specific attentional disorders and facial emotional recognition. DISCUSSION-CONCLUSION: Our study emphasizes social cognition disorders in SK. These disorders could be considered as a phenotypic trait in the syndrome. The interest of better characterizing the cognitive phenotype of genetic disorders that can affect the neurodevelopment is to offer specific cognitive remediation strategies.


Assuntos
Cognição/fisiologia , Síndrome de Klinefelter/psicologia , Comportamento Social , Percepção Social , Adolescente , Adulto , Humanos , Síndrome de Klinefelter/fisiopatologia , Masculino , Testes Neuropsicológicos , Fenótipo , Inquéritos e Questionários , Adulto Jovem
5.
Prog Urol ; 23(9): 621-8, 2013 Jul.
Artigo em Francês | MEDLINE | ID: mdl-23830256

RESUMO

INTRODUCTION: Relations between sexual desire and testosterone are more complex than previously thought particularly in ageing males. METHODS: A Medline search of the existing literature utilizing terms testosterone, libido, sexual desire, hypogonadism, and andropause, was performed until January 2012. RESULTS: Testosterone is a physiological stimulator of sexual desire. In case of complete hypogonadism, libido is very low and testosterone treatment restores sexual desire. In epidemiological studies, the relationship between testosterone and sexual desire is statistically significant but less strict because of interactions with other factors which decrease both sexual desire and testosterone levels. It is especially the case in ageing males: in addition to a possible late-onset hypogonadism, other etiological factors (health, partnership, socioeconomical and psychological factors) and other sexual dysfunctions (such as erectile dysfunction) must be taken into account. CONCLUSION: The decrease of sexual desire is one of the symptoms seen in late-onset hypogonadism. The effect of testosterone replacement therapy is more obvious that testosterone is low and there are no other causes of impaired sexual desire. There is no evidence that testosterone therapy increases the risk of prostate cancer, benign prostatic hyperplasia or promotes the clinical expression of subclinical prostate cancer.


Assuntos
Disfunções Sexuais Fisiológicas , Disfunções Sexuais Psicogênicas , Testosterona/deficiência , Fatores Etários , Humanos , Libido/fisiologia , Masculino , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Disfunções Sexuais Fisiológicas/epidemiologia , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Psicogênicas/tratamento farmacológico , Disfunções Sexuais Psicogênicas/epidemiologia , Disfunções Sexuais Psicogênicas/etiologia , Sexualidade/fisiologia , Testosterona/fisiologia , Testosterona/uso terapêutico
6.
Andrologia ; 44(5): 349-54, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21486417

RESUMO

The aim of this study was to compare anti-Mullerian hormone (AMH) plasma levels in patients with azoospermia according to the physiopathology. In a prospective clinical study from April 2008 to March 2009 in University Hospital, we measured AMH levels in 49 consecutive patients with azoospermia. AMH plasma levels were correlated with FSH, inhibin B, bioavailable testosterone plasma levels and testicular volume and compared between nonobstructive azoospermia (NOA) and obstructive azoospermia (OA) and within four physiopathological subgroups of NOA: genetic, cryptorchidism, cytotoxic and unexplained. AMH, FSH, inhibin B, bioavailable testosterone plasma levels and testicular volumes were all related to each other. AMH plasma levels were lower in NOA relatively to OA. Lowest values were observed in cases of genetic NOA and on the other hand, the values observed in case of cytotoxic NOA were as high as the values observed in OA. FSH, inhibin B, bioavailable testosterone and testicular volume were not different between genetic and cytotoxic NOA. These results suggest that the decrease in AMH plasma levels is related to the origin of NOA, with low values in genetic NOA and values similar to OA in cytotoxic NOA. Further studies will be useful to understand the fine regulation of AMH production.


Assuntos
Hormônio Antimülleriano/sangue , Azoospermia/sangue , Espermatogênese/genética , Adulto , Azoospermia/etiologia , Azoospermia/genética , Criptorquidismo/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Inibinas/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testículo/anatomia & histologia , Testosterona/sangue
7.
Basic Clin Androl ; 30: 10, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685170

RESUMO

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) metamorphosed our medical practice. In early June 2020, more than 6,400,000 COVID-19 (coronavirus-19 disease) cases were diagnosed across the world and more than 380,000 deaths were linked to COVID-19. Many medical symptoms of COVID-19 were reported. We will focus, here, on potential impacts of COVID-19 on men's andrological health. Our society (French-speaking society of andrology, SALF) also emitted some recommendations in the andrological management of men infected by SARS-CoV-2. First, considering the fever and the potential presence of SARS-CoV2 in semen, SALF recommends waiting for 3 months (duration of one spermatogenesis cycle and epididymal transit) before re-starting ART in the case of men diagnosed COVID-19 positive. Whatever the nature of testosterone and COVID-19 relationships, we recommend an andrological examination, sperm parameters, and hormonal evaluation at the time of the COVID-19 is diagnosed, and several months later. Furthermore, we are concerned by the potential morbid-mortality of the COVID-19, which mainly affects men. This "andrological bias", if proven, must be reduced by specific andrological diagnosis, therapeutic and prophylactic measures. Research in this direction must be substantiated and financially supported over the next few months (years).


Le SRAS-CoV-2 (nouveau coronavirus ou coronavirus numéro 2 responsable du syndrome respiratoire aigu sévère) a métamorphosé notre pratique médicale. Début juin 2020, plus de 6,400,000 cas de COVID-19 (maladie à coronavirus 2019) ont été diagnostiqués dans le monde et plus de 380,000 décès ont été reliés à cette maladie. De nombreux symptômes médicaux de cette infection virale ont été signalés. Nous nous concentrerons, ici, sur les impacts potentiels de COVID-19 sur la santé andrologique des hommes. Notre société (Société d'andrologie de langue Française, SALF) émet ici quelques recommandations dans la prise en charge andrologique des hommes infectés par le SRAS-CoV-2. Tout d'abord, compte tenu de la fièvre et de la présence potentielle du SRAS-CoV2 dans le sperme, la SALF recommande d'attendre 3 mois (durée d'un cycle de spermatogenèse et transit épididymaire) avant de recommencer les techniques d'assistance médicale à la procréation pour les hommes diagnostiqués COVID-19 positifs. Quelle que soit la nature des relations entre la testostérone et l'infection à SARS-CoV-2, nous recommandons un examen andrologique, un examen des paramètres du sperme et une évaluation hormonale au moment du diagnostic de l'infection, ainsi qu'à distance (3­6 mois plus tard). De plus, nous sommes préoccupés par la morbidité et la mortalité potentielles de l'infection COVID-19, qui touche principalement les hommes. Ce "biais andrologique", s'il est. prouvé, doit être réduit par un diagnostic andrologique spécifique et des mesures thérapeutiques et prophylactiques. La recherche dans ce sens doit être étayée et soutenue financièrement au cours des prochains mois (années).

8.
Gynecol Obstet Fertil ; 37(6): 519-22, 2009 Jun.
Artigo em Francês | MEDLINE | ID: mdl-19447664

RESUMO

During their post-meiotic maturation, male germ cells undergo an extensive reorganization of their genome, during which histones become globally hyperacetylated, are then removed and progressively replaced by transition proteins and finally by protamines. The latter are known to tightly associate with DNA in the mature sperm cell. Although this is a highly conserved and fundamental biological process, which is a necessary prerequisite for the transmission of the male genome to the next generation, its molecular basis remains mostly unknown. We have identified several key factors involved in this process, and their detailed functional study has enabled us to propose the first model describing molecular mechanisms involved in post-meiotic male genome reprogramming. One of them, Bromodomain Testis Specific (BRDT), has been the focus of particular attention since it possesses the unique ability to specifically induce a dramatic compaction of acetylated chromatin. Interestingly, a mutation was found homozygous in infertile men which, according to our structural and functional studies, disrupts the function of the protein. A combination of molecular structural and genetic approaches has led to a comprehensive understanding of new major actors involved in the male genome reprogramming and transmission.


Assuntos
Epigênese Genética , Infertilidade Masculina/genética , Meiose/fisiologia , Espermatogênese/fisiologia , Acetilação , Cromatina/química , Cromatina/metabolismo , Epigênese Genética/fisiologia , Histonas/metabolismo , Humanos , Masculino , Meiose/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Espermatogênese/genética , Espermatozoides/metabolismo
9.
Andrology ; 5(4): 640-663, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28622464

RESUMO

Beside cytotoxic drugs, other drugs can impact men's fertility through various mechanisms. Via the modification of the hypothalamic-pituitary-gonadal axis hormones or by non-hormonal mechanisms, drugs may directly and indirectly induce sexual dysfunction and spermatogenesis impairment and alteration of epididymal maturation. This systematic literature review summarizes existing data about the negative impact and associations of pharmacological treatments on male fertility (excluding cytotoxic drugs), with a view to making these data more readily available for medical staff. In most cases, these effects on spermatogenesis/sperm maturation/sexual function are reversible after the discontinuation of the drug. When a reprotoxic treatment cannot be stopped and/or when the impact on semen parameters/sperm DNA is potentially irreversible (Sulfasalazine Azathioprine, Mycophenolate mofetil and Methotrexate), the cryopreservation of spermatozoa before treatment must be proposed. Deleterious impacts on fertility of drugs with very good or good level of evidence (Testosterone, Sulfasalazine, Anabolic steroids, Cyproterone acetate, Opioids, Tramadol, GhRH analogues and Sartan) are developed.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Fertilidade/efeitos dos fármacos , Infertilidade Masculina/induzido quimicamente , Espermatozoides/efeitos dos fármacos , Animais , Criopreservação , Dano ao DNA , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/fisiopatologia , Preservação da Fertilidade/métodos , Humanos , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Infertilidade Masculina/terapia , Masculino , Medição de Risco , Fatores de Risco , Comportamento Sexual/efeitos dos fármacos , Bancos de Esperma , Espermatogênese/efeitos dos fármacos , Espermatozoides/patologia
10.
Endocrinology ; 138(11): 4783-91, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9348206

RESUMO

In addition to the regulation of FSH secretion, it has been clearly shown that inhibin and activin have paracrine/autocrine effects in the gonads. We have studied the effect of human recombinant inhibin A and human recombinant activin A on immature porcine Leydig cells in vitro. Leydig cells were prepared by collagenase digestion of testes from 3-week-old piglets, purified on Percoll gradient, then cultured in a chemically defined medium. The cells were treated with increasing amounts of inhibin A or activin A (0.5-200 ng/ml). Direct application of either inhibin A or activin A on Leydig cells for 4 or 48 h did not stimulate basal testosterone secretion. Conversely, treatment of the cells for 48 h with either factor resulted in a dose-dependent increase in hCG-stimulated testosterone secretion (10[-9] M hCG, 2 h) with a maximal effect of 2.40 +/- 0.37- and 2.43 +/- 0.37-fold increases for inhibin A and activin A, respectively, and these changes were associated with a slight increase in LH/hCG-binding sites (1.37 +/- 0.19- and 1.24 +/- 0.11-fold increases). In addition, both inhibin A and activin A enhanced messenger RNA (mRNA) levels of LH/hCG receptor (2.75 +/- 0.40- and 2.53 +/- 0.60-fold increases) and cytochrome P450 17alpha-hydroxylase (6 +/- 1- and 3.5 +/- 0.6-fold increases), but had no effect on side-chain cleavage cytochrome P450 or cytochrome P450 aromatase mRNAs. 3beta-Hydroxysteroid dehydrogenase mRNA levels were increased (3.1 +/- 1.3-fold increase) by activin A, but not by inhibin A. However, inhibin A blocked the stimulatory action of activin A. In keeping with these changes in the steroidogenic enzyme mRNAs, both peptides enhanced the conversion of exogenous 22R-hydroxycholesterol and progesterone, but only activin A increased the conversion of dehydroepiandrosterone into testosterone. In conclusion, our findings demonstrate that both inhibin A and activin A have a stimulatory effect on immature porcine Leydig cell differentiated function in vitro. As inhibin has a stimulatory and activin has an inhibitory effect on rat Leydig cell function in vitro, the effects of these factors on Leydig cells seem to be species dependent.


Assuntos
Inibinas/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Ativinas , Animais , Animais Recém-Nascidos , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Feminino , Humanos , Inibinas/antagonistas & inibidores , Células Intersticiais do Testículo/metabolismo , Masculino , RNA Mensageiro/metabolismo , Receptores do LH/efeitos dos fármacos , Receptores do LH/genética , Receptores do LH/metabolismo , Proteínas Recombinantes/farmacologia , Suínos , Testosterona/metabolismo
11.
J Clin Endocrinol Metab ; 80(4): 1283-9, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7536204

RESUMO

Changes in the plasma levels of corticosteroid-binding globulin (CBG) and sex hormone-binding globulin (SHBG) from birth to adulthood suggest that growth factors might influence clearance and/or hepatic secretion of CBG and SHBG in humans. The effects of insulin-like growth factor I (IGF-I) and insulin on CBG and SHBG synthesis by a clone of human hepatoblastoma-derived (Hep G2) cell lines were therefore investigated. The results showed that the immunoconcentrations of CBG and SHBG, as well as total protein concentration in culture medium from Hep G2 cells, were decreased by IGF-I and insulin. However, although the CBG-to-total protein ratio was decreased dose dependently by IGF-I and insulin, IGF-I and insulin did not dose-dependently decrease the SHBG-to-total protein ratio. The steady state levels of CBG and SHBG messenger RNAs (mRNAs) were reduced dose dependently by IGF-I with a half-effect at 5.4 +/- 1.9 and 4.6 +/- 1.6 nmol/L, respectively, and by insulin with a half-effect at 4.3 +/- 1.1 and 4.3 +/- 1.4 nmol/L, respectively. The maximum inhibitory effect of IGF-I on CBG mRNA level was 48 +/- 17% of control values and 60 +/- 13% for SHBG mRNA level. The changes in CBG mRNA levels were quantitatively similar to the changes in CBG immunoconcentration in the Hep G2 medium. In contrast, the inhibitory effects of insulin were only 17 +/- 8% and 31 +/- 12% of control values on CBG and SHBG mRNAs and 37 +/- 4% and 43 +/- 4% on CBG and SHBG concentrations, respectively. These results demonstrate that IGF-I reduces CBG and SHBG production by Hep G2 cells by decreasing mRNA steady state levels. The discrepancy between the inhibitory effects of insulin on CBG and SHBG mRNAs and protein secretion suggests that insulin exercises its inhibitory effects mainly on the mechanism(s) of translation and/or excretion of CBG and SHBG. The respective effects of IGF-I and insulin in the regulation of CBG and SHBG levels during fetal life and pubertal development in humans merit further study.


Assuntos
Hepatoblastoma/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Insulina/farmacologia , Neoplasias Hepáticas/metabolismo , Globulina de Ligação a Hormônio Sexual/metabolismo , Transcortina/metabolismo , Proteínas de Transporte/metabolismo , Estradiol/farmacologia , Hepatoblastoma/patologia , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Neoplasias Hepáticas/patologia , Somatomedinas/metabolismo , Tiroxina/farmacologia , Células Tumorais Cultivadas
12.
J Clin Endocrinol Metab ; 83(1): 235-40, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9435448

RESUMO

Sex hormone-binding globulin (SHBG) is the specific plasma transport protein for sex steroid hormones in humans. Considerable variation in SHBG plasma concentration exists between individuals, irrespective of gender, body weight, or thyroid status. In the present work, the influence of carbohydrate chains on the half-life of human SHBG (hSHBG) was investigated using a rabbit model. A variant hSHBG, with a point mutation in exon 8 (GAC --> AAC) encoding an amino acid substitution (Asp327Asn), which introduces an additional consensus site for N-glycosylation, has recently been identified. This mutation suppresses a recognition site for the restriction enzyme Bbs-I, allowing the development of a simple restriction-fragments length polymorphism (RFLP) screening procedure. In a population of patients (272 female and 49 male) consulting in our Endocrinology Clinic, 48 patients (41 female and 7 male) were heterozygous for the variant hSHBG allele and 3 (2 female and 1 male) were homozygous. In this population, the total variant allele frequency was 0.083. The hSHBG genotype, as determined by RFLP, corresponded in all cases to the phenotype as determined by the migration profile of hSHBG by Western blot analysis. The influence of such an additional glycosylation site on the biological half-life of variant hSHBG was investigated. SHBG from serum of patients carrying one of the three hSHBG genotypes was purified and labeled with biotin, then injected into rabbits, as we have recently described for rabbit SHBG. Biotinylated hSHBG was captured from rabbit serum samples on tubes coated with an anti-hSHBG antibody and detected by luminometry with the streptavidine-alkaline phosphatase-dioxetane (AMPPD) system. The results showed that the half-life value was significantly higher (P < 0.05) for SHBG purified from homozygous variant serum (t1/2 beta = 51.43 +/- 1.15 and 63.63 +/- 3.92 h, for male and a female subjects SHBG respectively) than for SHBG purified from heterozygous variant serum (t1/2 beta = 40.19 +/- 0.12 h) or wild-type (t1/2 beta = 38.18 +/- 7.22 h). This study demonstrated that an additional carbohydrate chain on hSHBG decreases the clearance rate of this protein. The low frequency of this variant allele means that further study will be required to determine whether it is associated with higher serum SHBG concentration.


Assuntos
Variação Genética , Mutação Puntual , Globulina de Ligação a Hormônio Sexual/genética , Globulina de Ligação a Hormônio Sexual/farmacocinética , Hiperplasia Suprarrenal Congênita , Alelos , Substituição de Aminoácidos , Animais , Doenças do Sistema Endócrino/genética , Éxons , Feminino , Frequência do Gene , Genótipo , Glicosilação , Meia-Vida , Humanos , Masculino , Taxa de Depuração Metabólica , Oligospermia/genética , Fenótipo , Coelhos , Globulina de Ligação a Hormônio Sexual/química
13.
J Clin Endocrinol Metab ; 67(1): 180-5, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2967850

RESUMO

Whether GnRH agonist treatment leads to reduced gonadotropin secretion and tumor volume in patients with gonadotropin-secreting pituitary adenomas is controversial. We studied the effect of GnRH analog treatment in two such patients, one with a recurrent FSH- and LH-secreting pituitary adenoma (patient 1) and one with a recurrent FSH- and alpha-subunit-secreting pituitary adenoma (patient 2). Patient 1 was treated with 200 micrograms Buserelin daily for 65 days, and patient 2 received three injections of 3 mg [D-Trp6]-LHRH formulated in microcapsules at 21-day intervals. In both patients, plasma FSH, LH (RIA), and alpha-subunit concentrations increased initially and remained above the pretreatment values throughout the treatment period. Plasma LH, measured by immunoradiometric assay, remained well above the detection limit. Plasma bioactive LH and testosterone became undetectable in patient 2, but did not change in patient 1. In neither patient did pituitary tumor size (determined by computed tomographic scan) change during treatment. We conclude that 1) the overall effect of GnRH analogs in patients with gonadotroph cell adenomas is stimulation of gonadotropin release by the tumor, although LH release varies according to how plasma LH is measured, possibly related to the origin of the hormone (normal or tumor gonadotroph cells), and 2) GnRH analog treatment does not reduce tumor size.


Assuntos
Adenoma/tratamento farmacológico , Busserrelina/uso terapêutico , Hormônio Liberador de Gonadotropina/análogos & derivados , Gonadotropinas Hipofisárias/metabolismo , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Hipofisárias/tratamento farmacológico , Adenoma/sangue , Adenoma/metabolismo , Adulto , Avaliação de Medicamentos , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/metabolismo , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/metabolismo , Estimulação Química , Testosterona/sangue , Fatores de Tempo , Pamoato de Triptorrelina
14.
J Clin Endocrinol Metab ; 80(7): 2057-62, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7608255

RESUMO

Evidence suggests that hyperinsulinemic insulin resistance may increase serum levels of ovarian androgens and reduce sex hormone-binding globulin (SHBG) levels in humans. The present study was conducted to assess the effect of administration of the biguanide metformin, a drug commonly used in the treatment of diabetes mellitus, on androgen and insulin levels in 24 hirsute patients. The patients selected for the study were obese, with a body mass index higher than 25 kg/m2 and high fasting insulin (> 90 pmol/L) and low SHBG levels (< 30 nmol/L). All patients were given a low calorie diet (1500 Cal/day) and randomized for either metformin administration at a dose of 850 mg or a placebo, twice daily for 4 months, in a double blind study. In the placebo group, diet resulted in a significant decrease in body mass index (30.8 +/- 1.0 vs. 32.7 +/- 1.5 kg/m2; P < 0.0001), fasting insulin (127 +/- 11 vs. 156 +/- 14 pmol/L; P < 0.01), non-SHBG-bound testosterone (0.19 +/- 0.02 vs. 0.28 +/- 0.03 nmol/L; P < 0.02), androstenedione (5.8 +/- 0.5 vs. 9.0 +/- 1.1 nmol/L; P < 0.03), and 3 alpha-diolglucuronide (8.6 +/- 1.1 vs. 11.7 +/- 1.9; P < 0.005) plasma concentrations and a significant increase in the glucose/insulin ratio (0.047 +/- 0.005 vs. 0.035 +/- 0.003; P < 0.001) and plasma concentrations of SHBG (26.0 +/- 3.3 vs. 19.1 +/- 1.9 nmol/L; P < 0.001) and dehydroepiandrosterone sulfate (8.7 +/- 1.5 vs. 8.4 +/- 1.3; P < 0.05). Beneficial effects of diet were not significantly different in the patients who were given metformin instead of placebo. These results confirm that weight loss induced by a low calorie diet is effective in improving hyperinsulinemia and hyperandrogenism in obese and hirsute women. With our study design, metformin administration had no additional benefit over the effect of diet.


Assuntos
Androgênios/metabolismo , Dieta com Restrição de Gorduras , Dieta Redutora , Hirsutismo/fisiopatologia , Insulina/metabolismo , Metformina/uso terapêutico , Obesidade/fisiopatologia , Globulina de Ligação a Hormônio Sexual/análise , Androgênios/sangue , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Glicemia/metabolismo , Composição Corporal , Colesterol/sangue , HDL-Colesterol/sangue , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Hirsutismo/dietoterapia , Hirsutismo/tratamento farmacológico , Humanos , Insulina/sangue , Secreção de Insulina , Obesidade/dietoterapia , Obesidade/tratamento farmacológico , Placebos , Triglicerídeos/sangue
15.
J Clin Endocrinol Metab ; 82(11): 3758-62, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9360537

RESUMO

Plasma corticosteroid-binding globulin (CBG) concentrations decrease dramatically in patients with septic shock or burn injury. This decrease suggests that mediators of the acute phase response, such as cytokines and glucocorticoid hormones, might influence clearance as well as liver synthesis of CBG in humans. The present study investigated the effects of interleukin-6 (IL-6), IL-1 beta, and dexamethasone on CBG synthesis by a clone of human hepatoblastoma-derived (HepG2) cell line. In culture medium from HepG2 cells, the immunoconcentration of CBG and the levels of CBG messenger ribonucleic acid (mRNA) were dose dependently decreased in the presence of IL-6 concentrations ranging from 0.1-10 ng/mL. The percent decrease in CBG immunoconcentration was quantitatively similar to the percent decrease in CBG mRNA levels (29 +/- 6% and 39 +/- 15%, respectively, of control values). In contrast, and as expected, IL-6 dose dependently increased the mRNA levels (164 +/- 22% of control values) of alpha 1-antitrypsin, a positive acute phase protein, but did not affect the immunoconcentration of sex hormone-binding globulin, another liver protein. Dexamethasone alone did not significantly affect CBG secretion or mRNA levels, but did dose-dependently increase tyrosine amino-transferase mRNA levels, which increased to 252 +/- 16% of the control values. However, in combination with IL-6, dexamethasone had a significant additive effect on IL-6 inhibition of CBG secretion and mRNAs in HepG2 cells. IL-1 beta dose-dependently stimulated CBG secretion (156 +/- 10% of control values) with no significant effect on CBG mRNA levels. In addition, IL-1 beta significantly decreased the inhibitory effect of IL-6 on CBG secretion, but had no effect on the inhibitory effect of IL-6 on CBG mRNA levels. These results suggest that IL-1 beta acts on the posttranslation processing and/or secretion mechanisms of CBG in HepG2 cells. Together, the present results strongly support the hypothesis that the decrease in plasma CBG concentrations is associated with the increase in IL-6 and glucocorticoid levels reported in patients with septic shock and burn injury.


Assuntos
Citocinas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Hepatoblastoma/metabolismo , Neoplasias Hepáticas/metabolismo , Transcortina/genética , Meios de Cultivo Condicionados , Dexametasona/farmacologia , Interações Medicamentosas , Humanos , Interleucina-1/farmacologia , Interleucina-6/farmacologia , RNA Mensageiro , Células Tumorais Cultivadas
16.
J Clin Endocrinol Metab ; 82(5): 1426-33, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9141528

RESUMO

Interleukins (IL)-1 and -6 have been shown to be produced by several categories of cells in the rat testis and involved in the paracrine control of testicular function. Evidence of high amounts of IL-1 have been shown in the human testis, but nothing is known about its cellular origin. Furthermore, to our knowledge, the presence of IL-6 in the human testis has not yet been investigated. Therefore, the present study was aimed at identifying IL-1 and -6 expression and production within the human testis, using RT-PCR, bioassays, and enzyme linked immunosorbent assays. We demonstrated that IL-1 and -6 messenger RNA and proteins were produced constitutively in vitro by human Leydig cell- and Sertoli cell-enriched preparations. FSH only stimulated IL-6 production by Sertoli cell-enriched preparations, but increased the release of both IL-1 and -6 in germ cell-depleted Sertoli cell cultures. In addition, lipopolysaccharides and latex beads enhanced the production of both cytokines by Sertoli cell cultures, whereas human chorionic gonadotropin and lipopolysaccharides enhanced the release of both cytokines by Leydig cells. Enzyme linked immunosorbent assays and neutralization experiments revealed that human Sertoli cells produce essentially the alpha form of IL-1, whereas both forms, alpha and beta, are present in Leydig cells. The demonstration that human Leydig and Sertoli cells produce IL-1 and -6 under the control of gonadotropin hormones and exogenous factors, opens the possibility to study the involvement of these cytokines in the control of testis function, in normal and pathological conditions in men.


Assuntos
Interleucina-1/biossíntese , Interleucina-6/biossíntese , Células Intersticiais do Testículo/metabolismo , Células de Sertoli/metabolismo , Adulto , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Hormônio Foliculoestimulante/farmacologia , Humanos , Látex , Células Intersticiais do Testículo/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Microesferas , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Células de Sertoli/efeitos dos fármacos
17.
Neurobiol Aging ; 12(1): 25-30, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2002879

RESUMO

The effects of ageing on temporal regulation, general activity and memory were analysed in a two-lever DRL schedule. The task consisted in pressing on lever A and then waiting a minimum of time before pressing lever B to get the reinforcer. Adult and senescent rats were submitted to preliminary training followed by 5 DRL 5-second training sessions and 3 retention testing sessions after a 21-day break. Results showed that, relative to adults, senescent rats were slower to reach the 5-second DRL criterion, emitted fewer temporally regulated A-B response sequences and an equivalent amount of repetitive superfluous A-A and B-B response sequences. The quality of temporal regulation was evaluated by the coefficient of variation (CV) and the median of the A-B interresponse-time distribution. In training, aged rats exhibited a higher CV only during the first 10-minute periods of the sessions, and emitted median IRTs similar to those of adults. The B-A intertrial-intervals were longer in aged than in adult rats. No age-related differences appeared for efficiency. Finally, long-term retention was not affected in either age group. The results favour an interpretation in terms of temporary recall memory deficit with a preservation of temporal regulation capacity, rather than age-related motor and motivational differences.


Assuntos
Envelhecimento/fisiologia , Comportamento Animal , Memória/fisiologia , Atividade Motora/fisiologia , Lobo Temporal/fisiologia , Análise de Variância , Animais , Masculino , Ratos , Ratos Endogâmicos , Análise e Desempenho de Tarefas
18.
Medicine (Baltimore) ; 74(1): 42-7, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7837969

RESUMO

The high frequency of cystic fibrosis (CF) mutations in males with absence of vas deferens supported the hypothesis of a primarily genital phenotype of CF disease. To consider the idea of an attenuated form of CF, we investigated 14 men with congenital bilateral aplasia of the vasa deferentia. All patients were consulting for infertility and none was known to have CF. The median age was 30.5 years (range, 20-38 yr). DNA analysis for 22 CF mutations showed at least 1 mutation in 10 patients (71%), whereas the CF carrier frequency is only 4% in the general population. Three compound heterozygotes were identified, all carriers of the R117H mutation. The sweat test was considered positive in 6 patients (43%), and a high frequency of radiologic evidence of sinus disease (8 patients) and of elevated antibodies to Pseudomonas (8 patients) was found. Only 2 patients were free of all these criteria for CF disease. This study strengthens the hypothesis that absence of vas deferens is an attenuated form of CF. We propose a combination of tests including DNA study, computerized tomographic scan of the paranasal sinuses, and testing of anti-Pseudomonas antibodies when the sweat test is inconclusive.


Assuntos
Fibrose Cística/diagnóstico , Ducto Deferente/anormalidades , Adulto , Cloretos/análise , Fibrose Cística/complicações , Fibrose Cística/genética , Triagem de Portadores Genéticos , Genótipo , Humanos , Infertilidade Masculina/complicações , Masculino , Suor/química
19.
Mol Cell Endocrinol ; 144(1-2): 59-69, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9863627

RESUMO

Since recombinant hormones are considered as safer and more reliable in their bioactivity than extractive hormones, the recently available human recombinant luteinizing hormone (r-hLH), will probably replace hCG in the near future, for clinical purposes. This prompted us to investigate whether or not, and by which mechanisms, r-hLH can induce a desensitization of signal transduction and/or an up-regulation of steroidogenic capacity in Leydig cells. The effects of a 30 min to 24 h exposure to r-hLH (10(-9) M) on the differentiated functions of cultured immature porcine Leydig cells were studied by measuring the following parameters: LH/hCG receptor number and mRNA, hCG-, cholera toxin- and forskolin-induced cAMP production, G protein alphas subunit content of the membrane, hCG-, cholera toxin-, forskolin-, 8Br-cAMP-, 22R-OH-cholesterol-, progesterone-, 170H-progesterone-, DHEA-, delta4-androstenedione-induced testosterone secretion and StAR, 3beta-HSD, cytochrome P-450scc and P-450c17 mRNAs. hCG binding sites and LH/hCG receptor mRNA were slowly down regulated by r-hLH, reaching 47+/-1 and 18+/-7% of control at 24 h, respectively. Down-regulation of both hCG- and cholera toxin-induced cAMP production occurred earlier and was more marked, and at 24 h represented only 2.7+/-0.5 and 12.5+/-3.6% of control. Due to the synergistic effect of r-hLH and forskolin on cAMP production, the forskolin-induced cAMP was higher in r-hLH treated than in control cells, but this response also declines with time and was, at 24 h, only 32% of that observed at 30 min. This decreased cAMP production was associated with a less marked decline in the amount of membrane content of Galphas protein. The testosterone production in response to hCG, cholera toxin, forskolin and 8Br-cAMP declined to reach a nadir at 6 h but increased thereafter and at 24 h was significantly higher than in control cells. In contrast, the conversion of several precursors into testosterone remained stable or increased slightly during the first hours of r-hLH treatment and significantly increased at 24 h and this was associated with an increase of StAR, 3beta-HSD, P-450scc and P-450c17 mRNAs. Taken together, the present results indicate that, despite the marked down-regulation of transmembrane signaling, r-hLH increased the steroidogenic capacity of Leydig cells by increasing the expression of several genes encoding the proteins involved in testosterone synthesis.


Assuntos
Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Toxina da Cólera/farmacologia , Gonadotropina Coriônica/metabolismo , Gonadotropina Coriônica/farmacologia , Colforsina/farmacologia , AMP Cíclico/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/agonistas , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroxiesteroide Desidrogenases/genética , Cinética , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Fosfoproteínas/genética , RNA Mensageiro/análise , Receptores do LH/genética , Receptores do LH/metabolismo , Proteínas Recombinantes/farmacologia , Suínos , Testosterona/metabolismo
20.
Psychopharmacology (Berl) ; 106(2): 215-20, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1549649

RESUMO

The effects of central cholinergic blockade on the temporal regulation of behaviour were studied with a two-level DRL schedule. Five-month-old male Wistar rats had to press lever A and then wait for a minimum of 5 s before pressing lever B to obtain the reinforcer (sweetened milk). After a stable baseline performance, subjects were injected in random order with the general cholinergic blocker, scopolamine, 0.15 and 0.5 mg/kg, the peripheral cholinergic blocker, methylscopolamine, 0.15 and 0.5 mg/kg, and a combination of the cholinesterase inhibitor, physostigmine, 0.2 mg/kg, and scopolamine, 0.5 mg/kg. Each drug treatment was separated by 2 days of saline treatment. Results showed that scopolamine at 0.5 mg/kg significantly impaired the temporal regulation of the A-B response sequence: the median A-B inter-response time (IRT) was shortened and the coefficient of variation of the A-B IRT distribution was increased, thus revealing a loss in the sensitivity to time. This disruption of accurate timing behaviour lowered efficiency. The drug changed neither the duration of the B-A interval nor the A-B response rate, but significantly increased the rate of the superfluous B-B sequences. Methylscopolamine was without effects and physostigmine totally or partially reversed all the scopolamine effects. These results suggest that scopolamine at 0.5 mg/kg specifically affected the mechanism(s) underlying response timing, and that the effects were not secondary to changes in activity or motivation. They partly corroborate data obtained in other procedures and support the idea that the central cholinergic system is involved in the temporal regulation of behaviour.


Assuntos
Comportamento Animal/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Animais , Masculino , Motivação , N-Metilescopolamina , Fisostigmina/farmacologia , Ratos , Ratos Endogâmicos , Esquema de Reforço , Escopolamina/farmacologia , Derivados da Escopolamina/farmacologia , Paladar/efeitos dos fármacos
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