RESUMO
It is a known fact that abnormal seminal liquid specimens contain abnormal amounts of oxygen free radicals and reactive oxygen species (ROS), and that the use of antioxidant molecules both in vivo and in vitro leads to improvement of semen quality in terms of motility, reduction in DNA damage, with obvious consequences on the fertilization potential. Myo-inositol has been observed to have anti-oxidant properties and be present in much greater concentrations specifically in seminal liquid than in the blood. Moreover, there seems to be a direct relationship between myo-inositol and mitochondrial membrane potential (MMP) and sperm motility. Studies performed in vivo have demonstrated that a dietary supplementation with myo-inositol in men undergoing assisted reproduction techniques may improve sperm quality and motility in oligoasthenospermia (OAT) patients. In the following study we utilized myo-inositol in vitro to verify its effect on semen quality in both normal and OAT patients undergoing in vitro fertilization (IVF) with respect to standard sperm medium. In vitro incubation of seminal liquid carried out using myo-inositol (Andrositol-Lab, Lo.Li. Pharma-Roma, Italy) at a concentration of 15 µl/ml improved progressive motility in both normospermia and OAT subjects. In our opinion, myo-inositol may prove to be a useful strategy to improve sperm preparation for clinical use in IVF.
Assuntos
Astenozoospermia/tratamento farmacológico , Fertilização in vitro/métodos , Inositol/farmacologia , Oligospermia/tratamento farmacológico , Motilidade dos Espermatozoides/efeitos dos fármacos , Complexo Vitamínico B/farmacologia , Adulto , Humanos , MasculinoRESUMO
The steroidogenic endocrine glands and local synthesis both contribute to the pool of steroids present in the central nervous system and peripheral nervous system. Although the synthesis of neurosteroids in the nervous system is now well established, the spectrum of respective functions in regulating neuronal and glial functions remains to be fully elucidated. From the concept of neurosteroids derives another treatment strategy: the use of pharmaceutical agents that increase the synthesis of endogenous neurosteroids within the nervous system. This approach has so far been hampered by lack of knowledge concerning the regulation of the biosynthetic pathways of neurosteroids and their relationship with sex steroids produced by the peripheral gland or with exogenous steroids. The present review summarizes some of the available clinical and experimental findings supporting the critical role of neurosteroids during fertile life and reproductive aging and their relationship with endogenous and exogenous sex steroids. The brain metabolism of synthetic progestins and the implications of DHEA treatment in postmenopausal women will also be discussed.
Assuntos
Neurotransmissores/fisiologia , Afeto , Envelhecimento , Comportamento , Lesões Encefálicas , Cognição , Desidroepiandrosterona/fisiologia , Desidroepiandrosterona/uso terapêutico , Sulfato de Desidroepiandrosterona/metabolismo , Feminino , Humanos , Masculino , Menopausa , Período Pós-Parto/fisiologia , Gravidez , Pregnanolona/fisiologia , Síndrome Pré-Menstrual , Progesterona/metabolismo , Progesterona/uso terapêutico , Reprodução/fisiologiaRESUMO
Polycystic ovary syndrome is one of the most common endocrine disorders in women of reproductive age. Features of PCOS are hyperandrogenism, chronic anovulation and polycystic ovaries on ultrasonography. Follicle development is a complex and carefully orchestrated phenomenon, involving gonadotropins and a rapidly expanding list of other intraovarian regulators, such as brain-derived neurotrophic factor (BDNF). The aim of this study is to evaluate BDNF in plasma and in follicular fluid in women affected by PCOS and in normal menstruating women. In PCOS patients the BDNF levels in plasma and in follicular fluid are higher than values obtained in healthy controls. Therefore we can hypothsize that high levels of luteinizing hormone, probably increase the secretion of BDNF in PCOS patients.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Líquido Folicular/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adolescente , Adulto , Fator Neurotrófico Derivado do Encéfalo/sangue , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Síndrome do Ovário Policístico/sangue , Progesterona/sangue , Adulto JovemRESUMO
BACKGROUND: Sexual desire is affected by endocrine and psychosocial factors. Menopausal hormonal changes are relevant to the causes of sexual dysfunction during reproductive aging. AIM: To evaluate the effects of different types of hormonal replacement therapy (HRT) on sexual function, frequency of sexual intercourse, and quality of relationship in early postmenopausal women. We recruited 48 healthy postmenopausal women aged 50-60 years (mean age 54.5 ± 3.3 years). Women with climacteric symptoms were uniformly randomized into three groups receiving either dehydroepiandrosterone (DHEA 10 mg) daily, or daily oral estradiol (1 mg) plus dihydrogesterone (5 mg), or daily oral tibolone (2.5 mg) for 12 months. Women who refused hormonal therapy were treated with oral vitamin D (400 IU). Efficacy was evaluated using the McCoy Female Sexuality Questionnaire before treatment and after 12 months. We evaluated the hormonal profile before treatment and after 3, 6 and 12 months. RESULTS: The groups receiving DHEA or HRT reported a significant improvement in sexual function compared to baseline (p < 0.001 and p < 0.01, respectively) using the McCoy total score. The quality of relationship was similar at baseline and after 3, 6 and 12 months of treatment. There were significant increases in the numbers of episodes of sexual intercourse in the previous 4 weeks in women treated with DHEA, HRT and tibolone in comparison with the baseline value (p < 0.01, p < 0.05, p < 0.01, respectively). No changes in the McCoy score occurred in women receiving vitamin D. CONCLUSIONS: Daily oral DHEA therapy at the dose of 10 mg, HRT and tibolone all provided a significant improvement in comparison with vitamin D in sexual function and in frequency of sexual intercourse in early postmenopausal women.
Assuntos
Climatério/efeitos dos fármacos , Desidroepiandrosterona/administração & dosagem , Terapia de Reposição Hormonal , Norpregnenos/administração & dosagem , Pós-Menopausa , Sexualidade/efeitos dos fármacos , Climatério/fisiologia , Didrogesterona/administração & dosagem , Estradiol/administração & dosagem , Moduladores de Receptor Estrogênico/administração & dosagem , Feminino , Seguimentos , Hormônios Esteroides Gonadais/sangue , Humanos , Pessoa de Meia-Idade , Radioimunoensaio , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: Allopregnanolone, a neuroactive steroid mainly secreted by adrenals and gonads, is a hormone that seems to play a role in precocious puberty, as demonstrated by its high baseline levels found in girls with central precocious puberty (CPP). Allopregnanolone concentrations significantly increase after GnRH and ACTH stimulation test suggesting both its ovarian and adrenal production. AIM: Aim of this study was to evaluate allopregnanolone concentrations after GnRH and GnRH agonist analog stimulation test in girls with CPP to better establish its secretion source. SUBJECTS AND METHODS: Gonadotropins and steroid hormones were evaluated in different days after GnRH and triptorelin stimulation test in 15 CPP girls. RESULTS: After GnRH stimulation, LH, FSH, and allopregnanolone concentrations significantly increased (p<0.05). After triptorelin administration LH, FSH, estradiol and DHEAS levels significantly increased (p<0.05), while allopregnanolone concentrations significantly decreased (1.08±0.24 vs 0.87±0.28 nmol/l; p=0.003). CONCLUSIONS: The different response of allopregnanolone to GnRH and GnRH agonist analog might reflect the agonist and antagonist action exerted by these secretagogues. Our data suggest the prevalent gonadal allopregnanolone production in CPP subjects and the usefulness of its measurement in the diagnosis of CPP.
Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/uso terapêutico , Testes de Função Hipofisária/métodos , Pregnanolona/sangue , Puberdade Precoce/diagnóstico , Pamoato de Triptorrelina/uso terapêutico , Determinação da Idade pelo Esqueleto , Criança , Pré-Escolar , Regulação para Baixo , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Genitália Feminina/diagnóstico por imagem , Humanos , Hormônio Luteinizante/sangue , Pregnanolona/metabolismo , Puberdade Precoce/sangue , Puberdade Precoce/metabolismoRESUMO
BACKGROUND: Plasma brain-derived neurotrophic factor (BDNF) levels are associated with the hormonal status of women. Moreover, the suprachiasmatic nucleus appears to be implicated in the modulation of BDNF central levels. We aimed to investigate whether BDNF circadian rhythms exist in women and if there is a relationship with cortisol circadian rhythmicity. Moreover, we aimed to establish whether the hormonal status influences BDNF diurnal variations. METHODS: A total of 30 women were studied: 10 fertile ovulatory women, 10 women undergoing oral contraceptive (OC) therapy and 10 post-menopausal women. Basal BDNF and estradiol levels were assayed in blood samples collected after overnight fasting at regular intervals (08:00, 12:00, 16:00, 20:00, 24:00). BDNF and cortisol levels were measured in samples collected during the follicular and luteal phases in ovulatory women and once a month in OC and post-menopausal women. RESULTS: Luteal BDNF levels were significantly higher than follicular levels in fertile women (P < 0.001). In OC women, BDNF levels were similar to the follicular BDNF levels, whereas in post-menopausal women, they were significantly lower (P < 0.001). BDNF showed a diurnal rhythm in the follicular phase and in women undergoing OC, although the diurnal rhythm was blunted in the luteal phase. In post-menopausal women, BDNF and cortisol levels significantly decreased during the day. CONCLUSIONS: BDNF has a diurnal variation in women that is somewhat analogous to cortisol variation; however, the amplitude of the variation in BDNF levels appears to be influenced by ovarian function. Interactions between BDNF, the hypothalamus-pituitary-adrenal axis and sex steroids might play a critical role in the human homeostasis and adaptation.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Ritmo Circadiano , Anticoncepcionais Orais/uso terapêutico , Hidrocortisona/sangue , Ciclo Menstrual/sangue , Pós-Menopausa/sangue , Adulto , Idoso , Ritmo Circadiano/fisiologia , Estradiol/sangue , Feminino , Fase Folicular/sangue , Humanos , Fase Luteal/sangue , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To evaluate whether a virtual reality workstation (Fetouch system) offering three-dimensional (3D) fetal visual and kinesthetic interaction may affect maternal stress. METHODS: Maternal-fetal visual and kinesthetic interaction was obtained through a haptic interface based on 3D reconstruction of sequencial bi-dimensional ultrasound images of the fetus. Maternal stress was assessed before and after visual/kinesthetic interaction with the fetus: 1) by using the State Trait Anxiety Inventory-Form Y (STAI) test, and 2) by measuring salivary cortisol levels. Statistical analysis was performed by paired t test and analysis of variance for repeated measures. RESULTS: After the fetal visual and kinesthetic experiences, a significant reduction was observed in anxiety (low state anxiety group, P < .0034; high state anxiety group, P < .0108), as well as in salivary cortisol concentration (P < .0004). CONCLUSION: Physical interaction with the fetus through a 3D model may reduce maternal stress.
Assuntos
Ansiedade , Relações Mãe-Filho , Estresse Psicológico , Tato , Interface Usuário-Computador , Adulto , Feminino , Humanos , Hidrocortisona/análise , Imageamento Tridimensional , Cinestesia , Entrevista Psiquiátrica Padronizada , Gravidez , Saliva/químicaRESUMO
INTRODUCTION: Estetrol (E4), a naturally occurring estrogen produced exclusively by human fetal liver, is currently being evaluated for potential use in contraception and menopausal care in humans. The present study was designed to profile E4 effects on the central nervous system, to assess the in vivo effects of E4 administration on Beta-Endorphin (ß-END) release in specific brain structures and to evaluate whether E4 has synergic or antagonistic effects on estradiol-mediated ß-END synthesis. EXPERIMENTAL: Intact female adult rats received different doses of E4 and ovariectomized (OVX) rats received different doses of E4 or E2V or combinations of both drugs. The concentrations of ß-END were assessed in the frontal and parietal cortex, hippocampus, hypothalamus, neurointermediate lobe, anterior pituitary and plasma. RESULTS: E4 at the dose of 1mg/kg/day did not alter ß-END content in most brain areas, as well as, plasma levels of intact animals E4 administered at a dose of 5mg/kg/day decreased ß-END content in the hippocampus, hypothalamus, and in the neurointermediate lobe, as well as, plasma levels, compared to intact animals receiving vehicle. E4 increased ß-END values in the frontal cortex, but not in the plasma, following the administration of 1mg/kg/day in OVX rats, whereas treatment with 5mg/kg/day in OVX rats induced a significant increase in ß-END levels in most brain areas and in the plasma. However, in the presence of estradiol, E4 showed an estrogen-antagonistic effect in selected brain structures at the dose of 5mg/kg/day and in plasma levels of ß-END at the dose of 1mg/kg/day and 5mg/kg/day. CONCLUSION: In OVX rats, E4 increases CNS and peripheral levels of ß-END, behaving as a weak estrogen-agonist. The antagonistic effect observed after combined estradiol and E4 administration further profiles E4 as a natural SERM.
Assuntos
Estetrol/farmacologia , beta-Endorfina/metabolismo , Animais , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Sinergismo Farmacológico , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Ovariectomia , Ratos , Ratos WistarRESUMO
Human placenta expresses subunit messenger RNAs for synthesizing inhibin A and B. Experimental studies have shown an effect of inhibins on placental hormone secretion, but an endocrine function is suggested by the high levels in maternal circulation. Although information is available on the changes of inhibin A in serum of healthy pregnant women, data on inhibin B levels are limited to early gestation. The aim of the present study was to investigate the changes of inhibin B levels in maternal circulation in healthy pregnant women throughout gestation, and to evaluate whether early pregnancy disturbances or gestational diseases are characterized by abnormal inhibin B levels. The protocol included various groups of pregnant women. A longitudinal evaluation of serum inhibin B levels was done at specific intervals (8-12, 13-18, 19-24, 25-28, 29-33, and 34-40 weeks) in the following groups: 1) healthy pregnant women (n = 13); 2) women at risk of hypertension who did not develop hypertension (n = 8); and 3) women with chronic hypertension (n = 13). In women in group 1, a blood sample was also obtained in the postpartum period (12, 24, and 48 h after delivery). Other pregnant women with abnormal bleeding in the first trimester were studied; they were subdivided into women with ongoing pregnancy (n = 12); and women with miscarriage (n = 22); a control group of healthy pregnant women at the same gestational age was also included (n = 18). A final group of women with gestational diseases (n = 34) was included in the study and included women with: 1) pregnancy-induced hypertension (n = 10); 2) preeclampsia (n = 17); and 3) intrauterine fetal growth retardation (n = 7). A group of healthy nonpregnant women (n = 9) was used as controls, and a blood specimen was collected during both the early- to midfollicular and midluteal phases of the menstrual cycle. Serum dimeric inhibin B levels were measured by using a double-antibody enzyme-linked immunoadsorbent assay. Early gestation inhibin B levels were similar to those of nonpregnant controls and showed a significant rise during the third trimester (P < 0.01). The highest maternal serum inhibin B levels were found at term (P < 0.01). Values significantly returned to control levels within 12-48 h (P < 0.01) after placental delivery. Women at risk of hypertension showed a similar gestational-related increase of inhibin B levels during the third trimester, without any significant difference when compared with healthy women. Women with chronic hypertension showed significantly lower levels at term (P < 0.01). Women with pregnancy-induced hypertension or preeclampsia, or who were carrying a fetus with intrauterine growth retardation showed serum inhibin B levels during the third trimester of gestation consistently lower than in control healthy women at the same gestational age (P < 0.001, mean +/- SEM). Maternal serum inhibin B levels in women with early pregnancy bleeding or miscarriage were similar to those of healthy pregnant women at the same gestational age, independent from the outcome of gestation. The present study showed that maternal serum inhibin B levels increase in the last trimester of normal pregnancy, with low levels in women with hypertensive disturbances or intrauterine growth retardation.
Assuntos
Inibinas/sangue , Inibinas/química , Complicações na Gravidez/sangue , Gravidez/sangue , Adulto , Dimerização , Feminino , Retardo do Crescimento Fetal/sangue , Humanos , Hipertensão/sangue , Estudos Longitudinais , Pré-Eclâmpsia/sangue , Complicações Cardiovasculares na Gravidez/sangue , Valores de ReferênciaRESUMO
Allopregnanolone is a neuroactive steroid involved in modulating behavioral functions, stress, and neuroendocrine axes in rats. Changes in plasma allopregnanolone levels throughout the menstrual cycle have been reported in healthy women, but there exists no information on the possible gender or age-related changes or on the source(s) of circulating allopregnanolone. The aim of the present study was to assess serum allopregnanolone concentrations according to gender, menstrual cycle, age, and menopause in normal men and women; serum progesterone (P) and dehydroepiandrosterone (DHEA) levels were evaluated in the same specimens. In addition, the possible source of circulating allopregnanolone in fertile women was investigated by using stimulatory and inhibitory endocrine tests acting on the ovary and/or adrenal cortex. The present study included 189 fertile women, 112 postmenopausal women, and 46 men. Serum steroid levels were determined after extraction, using specific RIAs. Allopregnanolone levels in fertile women in the follicular phase were similar to those in age-matched men; no significant difference was found between fertile women in the follicular phase and postmenopausal women. The highest levels were found in fertile women during the luteal phase (P < 0.01). An age-related decrease was observed in men (P < 0.01), but not in women. P and DHEA levels were significantly higher in women than in men and were higher in fertile women than in postmenopausal women (P < 0.01). Both P and DHEA showed an age-related decrease in men and women (P < 0.01). Serum allopregnanolone and P, but not DHEA, significantly increased in response to a GnRH test, whereas corticotropin-releasing factor and ACTH tests elicited a significant increase in allopregnanolone, P, and DHEA levels (P < 0.01). The suppression of adrenal steroidogenesis by dexamethasone markedly reduced both allopregnanolone and DHEA serum levels (P < 0.01). In conclusion, the present study demonstrated that although men show an age-related decrease, serum allopregnanolone levels in women do not change with age and correlate with P levels during the menstrual cycle and in response to endocrine tests. Ovary and adrenal cortex may be major sources of circulating allopregnanolone in fertile women.
Assuntos
Córtex Suprarrenal/metabolismo , Envelhecimento , Ovário/metabolismo , Pregnanolona/sangue , Caracteres Sexuais , Hormônio Adrenocorticotrópico , Adulto , Idoso , Hormônio Liberador da Corticotropina , Desidroepiandrosterona/sangue , Feminino , Fase Folicular/sangue , Hormônio Liberador de Gonadotropina , Humanos , Fase Luteal/sangue , Masculino , Menopausa/sangue , Menstruação/sangue , Pessoa de Meia-Idade , Progesterona/sangueRESUMO
OBJECTIVE: Allopregnanolone is a potent neuroactive steroid hormone produced in the brain and in peripheral endocrine glands. The present study investigated possible age-related variations in allopregnanolone content in brain areas, endocrine glands and serum of male rats. DESIGN: Wistar male rats were categorized into 5 groups (6 rats in each) according to age: 6, 12, 16, 18 and 20 months respectively. METHODS: Allopregnanolone content in acidic homogenates of brain cortex, hypothalamus, pituitary, adrenals and gonads was measured by a specific radioimmunoassay. Serum allopregnanolone, corticosterone and testosterone were also assayed by radioimmunoassay. RESULTS: Brain cortex allopregnanolone content decreased significantly with age, while hypothalamic allopregnanolone content remained constant until 18 months and increased significantly at 20 months. Pituitary content showed a significant age-related reduction. Adrenal allopregnanolone content remained constant until 18 months, and was significantly higher at 20 months. Testis and serum allopregnanolone contents showed significant age-related increases. Serum testosterone levels showed an age-related decrease, while no age-related variation in serum corticosterone was found. CONCLUSIONS: The present study showed a significant impact of aging on allopregnanolone contents in brain, endocrine glands and serum, showing an age-related decrease in brain cortex and pituitary, and an age-related increase in testes, adrenals and serum.
Assuntos
Envelhecimento/fisiologia , Química Encefálica/fisiologia , Glândulas Endócrinas/química , Pregnanolona/análise , Testículo/química , Glândulas Suprarrenais/química , Envelhecimento/sangue , Animais , Córtex Cerebral/química , Estudos de Coortes , Corticosterona/sangue , Reações Cruzadas , Hipotálamo/química , Soros Imunes/imunologia , Masculino , Hipófise/química , Pregnanolona/sangue , Radioimunoensaio , Ratos , Ratos Wistar , Ovinos , Testosterona/sangueRESUMO
OBJECTIVES: A progressive decline of plasma dehydroepiandrosterone (DHEA) levels occurs in women during aging related to the reduction of adrenocortical secretion. A specific action of DHEA on the central nervous system (CNS) is suggested by the improvement of psychological and physical well-being in postmenopausal women after DHEA supplementation. The aim of the present study was to investigate the neuroendocrine effects of short-term DHEA supplementation in postmenopausal women, evaluating changes of plasma beta-endorphin (beta-EP) and growth hormone (GH) before and after oral DHEA (100 mg/day) for 7 days in postmenopausal women (n = 6). METHODS: Before and after 7 days of DHEA supplementation, postmenopausal women underwent a neuroendocrine test with clonidine, an alpha 2 presinaptic agonist for adrenergic system (1.25 mg i.v.). Basal plasma DHEA, androstenedione (A), testosterone (T), estrone (E1) and estradiol (E2) levels were evaluated before and after treatment, while plasma beta-EP and GH levels were measured before and 15, 30, 45, 60 and 90 min after clonidine injection. RESULTS: Basal plasma beta-EP and GH levels did not show a significant difference before and after short-term DHEA administration, while circulating A, T, E1 and E2 significantly increased after treatment. The clonidine test induced a significant increase of plasma beta-EP levels in women after receiving DHEA supplementation but not before; conversely, plasma GM levels increased both before and after treatment. CONCLUSIONS: The present study indicates that short-term DHEA supplementation in postmenopausal women is able to restore the impaired response of pituitary beta-EP to clonidine, an alpha 2 presinaptic agonist. According to these data it is possible to hypothesize that DHEA could play a role in the psychological and physical well-being of postmenopausal women acting via a restoration of neuroendocrine control of antero-pituitary beta-EP secretion.
Assuntos
Desidroepiandrosterona/farmacologia , Hormônio do Crescimento Humano/efeitos dos fármacos , Sistemas Neurossecretores/efeitos dos fármacos , Pós-Menopausa/efeitos dos fármacos , beta-Endorfina/efeitos dos fármacos , Administração Oral , Androstenodiona/sangue , Androstenodiona/metabolismo , Clonidina , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/sangue , Desidroepiandrosterona/metabolismo , Estrona/sangue , Estrona/metabolismo , Feminino , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/metabolismo , Humanos , Pessoa de Meia-Idade , Sistemas Neurossecretores/metabolismo , Pós-Menopausa/sangue , Simpatolíticos , Testosterona/sangue , Testosterona/metabolismo , beta-Endorfina/sangue , beta-Endorfina/metabolismoRESUMO
BACKGROUND: Spaceflight causes a number of physiological changes in the human body. Most would consider space travel to be a stressful event even for well-trained astronauts. Should this be true, pituitary gonadotrophins (mainly LH) and testicular androgens, like testosterone (T), should decrease inflight in male astronauts. We therefore hypothesized that lowered testicular androgen levels might occur in men during spaceflight, due to stress-dependent lowered LH concentrations. METHODS: In order to test this hypothesis, on different day pre-, in- and postflight we assayed wake-time salivary and urinary T in four astronauts, as well as wake-time plasma levels of adrenocorticotropin (ACTH), cortisol (CS), LH, T and its peripherally active metabolite 3-alpha-diol glucuronide (3ADG). In order to compare clinical to subjective data, all 7 male crewmembers anonymously answered a daily questionnaire from pre- to postflight asking them to self-rate sexual drive and potency, muscle strength and mood. RESULTS: Salivary, urinary and plasma T, as well as 3ADG, decreased during flight, while LH unexpectedly increased inflight (p < 0.05). A parallel decrease in sexual drive was observed (p < 0.05). A dramatic recovery of salivary T was found on R + 1. CONCLUSIONS: This was the first time that spaceflight was demonstrated to cause temporary, still dramatic hypoandrogenism which was not due to blunted pituitary gonadotrophin secretion. The cause for hypoandrogenism is unknown but it may depend on fluid shift affecting testicular function or androgen distribution in various body compartments.
Assuntos
Hipogonadismo/fisiopatologia , Hipogravidade/efeitos adversos , Voo Espacial , Estresse Psicológico , Testículo/metabolismo , Testosterona/metabolismo , Adulto , Humanos , Hormônio Luteinizante/fisiologia , Masculino , Testículo/fisiologia , Equilíbrio HidroeletrolíticoRESUMO
AIM: Considering the hypothesis that some temporomandibular joint (TMJ) tissues could be a potential target for sexual hormones, the aim of the study was to evaluate estrogen (17-beta-estradiol) and progesterone serum levels in a young adult population affected by articular forms of temporomandibular disorders (TMD) versus a control group of healthy subjects. METHODS: A total of 35 patients with Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I Group II diagnosis of disk displacement and/or Group III diagnosis of arthralgia, osteoarthritis or osteoarthrosis, were recruited at the Section of Prosthetic Dentistry, Department of Neurosciences, University of Pisa, Italy, along with a sex- and age-matched group of 24 healthy controls. In all patients, 17-beta-estradiol, progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) serum levels were determined using a radioimmunoassay. A T-test was performed to compare mean 17-beta-estradiol and progesterone serum levels in the TMD groups with mean serum levels of their respective control groups. Significance was set at p<0.05. RESULTS: Significant differences between patients affected by TMJ disorders and healthy controls were found for serum concentration of 17-beta-estradiol, both in males (p<001) and in the luteal phase of the menstrual cycle in females (p<0.05). No difference was found for progesterone serum levels in the different experimental samples. CONCLUSIONS: The results of this study suggest that high serum estrogens levels might be implicated in the physiopathology of temporomandibular joint disorders, since subjects with these pathologies showed significantly higher serum levels with respect to a group of healthy controls.
Assuntos
Estradiol/sangue , Progesterona/sangue , Transtornos da Articulação Temporomandibular/sangue , Adulto , Feminino , Humanos , MasculinoRESUMO
INTRODUCTION: Estetrol (E4), a naturally occurring estrogen only produced by the human fetal liver, is being evaluated in human studies for potential use in contraception and menopausal care. The present study was designed to profile E4 in the central nervous system, to assess the in vivo effects of E4 administration on allopregnanolone (AP) synthesis in specific brain structures and to evaluate whether E4 has synergic or antagonistic effects on estradiol-mediated AP synthesis. MATERIAL AND METHODS: Intact female adult rats received different doses of E4, and ovariectomized OVX rats received different doses of E4 or E2V or combinations of both drugs. The concentrations of AP were assessed in the frontal and parietal cortex, hippocampus, hypothalamus, anterior pituitary, and serum. RESULTS: E4 did not alter AP in intact animals in any region. E4 at a dosage of 5mg/kg/day increased AP levels in different brain areas and in the serum of OVX animals. However, in the presence of estradiol, E4 showed an estrogen-antagonistic effect on the brain and serum levels of AP. CONCLUSION: E4 increases the CNS and peripheral levels of AP, behaving as a weak estrogen-agonist in OVX rats. The antagonistic effect observed with E2V co-administration further profile E4 as a natural SERM.
Assuntos
Biomarcadores/análise , Encéfalo/metabolismo , Estetrol/administração & dosagem , Ovariectomia , Pregnanolona/análise , Animais , Encéfalo/efeitos dos fármacos , Estetrol/farmacologia , Feminino , Radioimunoensaio , Ratos , Ratos WistarRESUMO
BACKGROUND: Brain-derived neurotrophic factor (BDNF) is a mediator of neuronal plasticity influencing learning, memory and cognitive behavior. The aim of this study is to assess plasma BDNF variations according to pubertal status. METHODS: A total of 110 subjects were included in the study. Blood samples were collected after overnight fasting. Plasma BDNF concentrations were measured by enzyme-linked immunosorbent assay. Gonadotrophins, sex steroids, and IGF-1 were also assessed. RESULTS: BDNF was positively correlated with platelet count and negatively associated with both BMI and age. BDNF levels in pubertal males were significantly lower than prepubertal males and both prepubertal and pubertal females. CONCLUSIONS: Plasma BDNF levels seem to be influenced by hormonal status. We demonstrate that parameters such as age or gender have a specific impact on stored and circulating BDNF blood levels and platelets remain the most important predictor of their concentration. Further studies are necessary to better understand the role of this neurotrophin in pubertal development.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Puberdade/sangue , Adolescente , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Plasticidade Neuronal/fisiologia , Projetos PilotoRESUMO
The aim of the present study was to evaluate the potential action of Nestorone (alone or in combination with estradiol valerate) on the level of allopregnanolone and of the opioid beta-endorphin in selected brain areas. Wistar ovariectomized rats were given 0.05 mg/(kg day) of estradiol valerate (E2V) or subcutaneous Nestorone at three dose levels: low dose (10 microg/(kg day)), antiovulatory dose (50 micro/(kg day)) and high dose (250 microg/(kg day)) with and without E2V. E2V therapy reversed the reduction of allopregnanolone and beta-endorphin induced by ovariectomy anywhere was analyzed except for the adrenal gland. Nestorone showed no effect on allopregnanolone concentration in serum or any part of the brain tissue when given alone while it had a synergistic increasing effect in allopregnanolone concentration in some parts of the brain (hippocampus, hypothalamus, anterior pituitary and serum) when given at high dose of 250 microg/(kg day) in combination with E2V. At lower doses it possesses a synergistic effect with E2V only in the hippocampus (at 50 microg/(kg day)) and in the anterior pituitary (at 10 and 50 microg/(kg day)). Nestorone administered alone at any dose led to significant increase in beta-endorphin levels in the hippocampus only while, in the high dose group, there was a significant increase in endorphin levels in anterior pituitary and hypothalamus in addition to hippocampus as compared to ovariectomized control rats. In addition, only the highest dose of Nestorone added to estrogen increased beta-endorphin levels of hippocampus and plasma. Thus the lower doses of Nestorone alone or in combination with estrogen do not seem to exert any great effect on both allopregnanolone and beta-endorphin. It is only the highest dose of Nestorone that increases allopregnanolone and beta-endorphin levels in selected brain areas, which are the hippocampus, the hypothalamus, the anterior pituitary and serum/plasma. This suggests that Nestorone at the antiovulatory dose levels may not alter the positive effects of estrogen treatment on mood and behaviour.
Assuntos
Anticoncepcionais Femininos/administração & dosagem , Neurotransmissores/metabolismo , Norprogesteronas/administração & dosagem , Pregnanolona/metabolismo , beta-Endorfina/metabolismo , Animais , Encéfalo/metabolismo , Feminino , Hipocampo/metabolismo , Hipotálamo/metabolismo , Infusões Subcutâneas , Modelos Animais , Ovariectomia , Ratos , Ratos WistarRESUMO
OBJECTIVE: Several studies demonstrated that obese subjects have a hyperactive hypothalamic-pituitary-adrenal axis and that sex steroid hormones have been closely related to the regulation of adiposity, either through direct or indirect physiological mechanisms. Allopregnanolone (3alpha-hydroxy-5alpha-pregn-20-one; AP) is a circulating neuroactive steroid hormone involved in the modulation of behavioral functions, stress and neuroendocrine axis. The aim of our study was to evaluate basal serum AP levels in obese children. SUBJECTS AND MEASUREMENTS: We studied 27 normal weight (NW) and 23 overweight (OW) girls. Gonadotropins and steroid hormones were assessed in all patients. RESULTS: Basal AP concentrations in OW girls were significantly higher than in NW controls (P=0.013). There was no difference found between the other gonadal and adrenal hormones. Considering the pubertal stage, we demonstrated that obese pubertal girls presented higher AP concentrations than prepubertal and pubertal NW ones (P=0.020), and higher dehydroepiandrosterone sulfate (DHEAS) levels with respect to prepubertal obese girls, and prepubertal and pubertal NW patients (P=0.025). AP and DHEAS were significantly directly related to weight (r=0.31 and r=0.54, respectively) and body mass index (r=0.29 and r=0.34, respectively). In pubertal OW girls, a significant positive correlation between AP and DHEAS (r=0.60), A (r=0.72) and luteinizing hormone (r=0.64) levels was demonstrated. CONCLUSION: The present study demonstrates that AP is hypersecreted in children and adolescent with OW involving DHEAS concentrations, too. Our data suggest a possible role of AP in the regulation of neuroendocrine axis related to obesity. We can also speculate that in OW girls, who could manifest emotional and behavioral problems, a part of higher levels of this neuroactive steroid might act as gamma-aminobutyric acid agonist producing anxiolytic-sedative effects.
Assuntos
Obesidade/sangue , Pregnanolona/sangue , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Hormônio Adrenocorticotrópico/sangue , Criança , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Gonadotropinas Hipofisárias/sangue , Humanos , Hidrocortisona/sangue , Obesidade/fisiopatologia , Puberdade/fisiologiaRESUMO
BACKGROUND: Brain-derived neurotrophic factor (BDNF) is a mediator of neuronal plasticity and influences learning, memory and cognitive behaviour. The aim of this study is to assess plasma BDNF variations according to hormonal status. METHODS: A total of 60 subjects were included: 20 fertile ovulatory women, 15 amenorrhoeic women and 25 postmenopausal women. Blood samples were collected after overnight fasting. For 5 out of the 20 fertile women, samples were collected every 2 days throughout the whole menstrual cycle. Following basal evaluation, 10 out of 25 postmenopausal women were administered a hormone replacement therapy (HRT) and reevaluated after 6 months of treatment. Plasma BDNF concentrations were measured by enzyme-linked immunosorbent assay. In fertile women, estradiol (E(2)), progesterone and gonadotrophins were also assessed. RESULTS: In fertile women, luteal phase levels of plasma BDNF were significantly higher than follicular phase levels (P < 0.001). BDNF increased from early follicular phase up to Day 14 of the cycle, reaching a pre-ovulatory peak, similar to E(2). A second rise took place during mid-luteal phase, with a peak on Day 24. Amenorrhoeic subjects, as well as postmenopausal women, showed significantly lower plasma BDNF levels compared with fertile females (P < 0.001). BDNF was positively correlated with E(2) and progesterone and negatively correlated with menopausal age. HRT restored BDNF levels to those present in fertile women during the follicular phase. CONCLUSIONS: Plasma BDNF levels are influenced by hormonal status. Modifications in BDNF circulating levels during the menstrual cycle suggest a potential role for gonadal sex hormones (E(2) and progesterone) in regulating neurotrophin expression.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Estradiol/metabolismo , Ovário/fisiologia , Progesterona/metabolismo , Adulto , Idoso , Amenorreia/metabolismo , Fator Neurotrófico Derivado do Encéfalo/química , Ensaio de Imunoadsorção Enzimática , Feminino , Terapia de Reposição Hormonal/métodos , Humanos , Ciclo Menstrual , Pessoa de Meia-Idade , Ovulação , Pós-MenopausaRESUMO
PURPOSE: The aim of the study was to measure circulating BDNF levels, a neurotrophin recently identified in the ovary, in parallel with estradiol, to verify if assessing this factor could add any predictive value to the outcome of in vitro fertilization. METHODS: Blood sampling for BDNF and estradiol was performed in 23 subjects undergoing IVF on day 1 (D1), day 8 (D8), day of HCG administration (DHCG) and day of oocyte retrieval.(DOR). RESULTS: There was a positive correlation between BDNF and estradiol throughout the stimulation cycle in all subjects. In both pregnant and nonpregnant patients, the values of BDNF grew significantly only between D8 and DHCG and remained constant until DOR. Between-group comparisons showed no statistically significant differences in both BDNF and estradiol values throughout the IVF cycle. CONCLUSION: Although BDNF plasma concentrations are not seemingly predictive of IVF outcome, this neurotrophin is highly correlated to estradiol levels and seems to be an important factor especially in the periovulatory period.