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1,209 result(s) for "Gonadotropin-Releasing Hormone - blood"
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Administration of increasing doses of gonadotropin-releasing hormone in men with spinal cord injury to investigate dysfunction of the hypothalamic–pituitary–gonadal axis
Study designProspective.ObjectivesTo determine the optimum gonadotropin-releasing hormone (GnRH) dose to identify dysfunction of the hypothalamic–pituitary–gonadal axis in men with spinal cord injury (SCI).SettingMetropolitan Area Hospitals, New York and New Jersey, USA.MethodsSCI men (16 hypogonadal (HG = serum testosterone <12.1 nmol/l) and 14 eugonadal (EG)) and able-bodied (AB) men (27 HG and 11 EG) were studied. GnRH (10, 50, and 100 μg) was randomly administered intravenously on three separate visits. Blood samples were collected post-GnRH for serum-luteinizing hormone (LH) and follicular-stimulating hormone (FSH).ResultsHG and EG men had a similar proportion of clinically acceptable gonadotropin responses to all three GnRH doses. The incremental gonadotropin responses to GnRH were not significantly different across the groups. However, in the SCI-HG group, GnRH of 100 μg resulted in the greatest integrated FSH response, and in the SCI-EG group, GnRH of 50 μg resulted in the greatest integrated LH response compared with the AB groups. A consistent, but not significant, absolute increase in gonadotropin release was observed in the SCI groups at all GnRH doses.ConclusionsLower doses of GnRH did not improve the ability to identify the clinical dysfunction of the hypothalamic–pituitary–gonadal axis. However, the absolutely higher SCI-HG FSH response to GnRH of 100 μg and a higher SCI-EG LH response to GnRH of 50 μg, along with a higher gonadotropin release at all GnRH doses, albeit not significant, suggests a hypothalamic–pituitary dysfunction in persons with SCI.
Role of emotional processing in depressive responses to sex-hormone manipulation: a pharmacological fMRI study
Sex-hormone fluctuations may increase risk for developing depressive symptoms and alter emotional processing as supported by observations in menopausal and pre- to postpartum transition. In this double-blinded, placebo-controlled study, we used blood−oxygen level dependent functional magnetic resonance imaging (fMRI) to investigate if sex-steroid hormone manipulation with a gonadotropin-releasing hormone agonist (GnRHa) influences emotional processing. Fifty-six healthy women were investigated twice: at baseline (follicular phase of menstrual cycle) and 16±3 days post intervention. At both sessions, fMRI-scans during exposure to faces expressing fear, anger, happiness or no emotion, depressive symptom scores and estradiol levels were acquired. The fMRI analyses focused on regions of interest for emotional processing. As expected, GnRHa initially increased and subsequently reduced estradiol to menopausal levels, which was accompanied by an increase in subclinical depressive symptoms relative to placebo. Women who displayed larger GnRHa-induced increase in depressive symptoms had a larger increase in both negative and positive emotion-elicited activity in the anterior insula. When considering the post-GnRHa scan only, depressive responses were associated with emotion-elicited activity in the anterior insula and amygdala. The effect on regional activity in anterior insula was not associated with the estradiol net decline, only by the GnRHa-induced changes in mood. Our data implicate enhanced insula recruitment during emotional processing in the emergence of depressive symptoms following sex-hormone fluctuations. This may correspond to the emotional hypersensitivity frequently experienced by women postpartum.
Comparing blastocyst quality and live birth rates of intravaginal culture using INVOcell™ to traditional in vitro incubation in a randomized open-label prospective controlled trial
Purpose The purpose of this study is to to compare the efficacy of intravaginal culture (IVC) of embryos in INVOcell™ (INVO Bioscience, MA, USA) to traditional in vitro fertilization (IVF) incubators in a laboratory setting using a mild pre-determined stimulation regimen based solely on anti-mullerian hormone (AMH) and body weight with minimal ultrasound monitoring. The primary endpoint examined was total quality blastocysts expressed as a percentage of total oocytes placed in incubation. Secondary endpoints included percentage of quality blastocysts transferred, pregnancy, and live birth rates. Methods In this prospective randomized open-label controlled single-center study, 40 women aged <38 years of age with a body mass index (BMI) of <36 and an AMH of 1–3 ng/mL were randomized prior to trigger to receive either IVC or IVF. Controlled ovarian stimulation was administered with human menopausal gonadotropin (hMG) in a fixed gonadotropin-releasing hormone (GnRH) agonist cycle based solely on AMH and body weight. A single ultrasound-monitoring visit was performed on the 10th day of stimulation. One or two embryos were transferred following 5 days of culture. Results IVF produced a greater percentage of total quality embryos as compared to IVC (50.6 vs. 30.7 %, p  = 0.0007, respectively). There was no significant difference between in IVF and IVC in the percentage of quality blastocysts transferred (97.5 vs. 84.9 %, p  = 0.09) or live birth rate (60 % IVF, 55 % IVC). Conclusions IVF was shown to be superior to IVC in creating quality blastocysts. However, both IVF and IVC produced identical blastocysts for transfer resulting in similar live birth rates. IVC using INVOcell™ is effective and may broaden access to fertility care in selected patient populations by ameliorating the need for a traditional IVF laboratory setting. Further studies will help elucidate the potential physiological, psychological, geographic, and financial impact of IVC on the delivery of fertility care.
Follicular fluid hormonal profile and cumulus cell gene expression in controlled ovarian hyperstimulation with recombinant FSH: effects of recombinant LH administration
Purpose Down-regulation with gonadodropin-releasing agonist (GnRH-a) protocol during IVF stimulation leads to a severe endogenous LH suppression, which may affect the follicular development. The aim of the study was to evaluate the effects of recombinant LH (r-LH) administration, during late follicular development stages, in recombinant FSH (r-FSH) stimulated cycles on follicular fluid (FF) parameters and on cumulus cell quality. Methods Twenty patients undergoing IVF were stimulated in a long GnRH agonist protocol with r-FSH alone or with r-LH supplementation when the leading follicle reached diameter of 14 mm. FF was collected at the time of oocyte retrieval from 32 follicles ≥ 18 mm. Serum FSH, LH, estradiol (E 2 ), and progesterone (P 4 ) were evaluated on the day of hCG administration. Intra-follicular E 2 , P 4 , AMH and TGF-β were assayed. Total RNA from 18 individual cumuli was isolated for gene expression analyses. Results R-LH increased FF P 4 levels. FF TGF-β levels and PTGS2 and HAS2 expression in cumulus cells (CCs) positively correlated with increased P 4 levels observed in FFs, while a negative correlation was found between P 4 and AMH levels. Conclusions FF positive correlation between P 4 and TGF-β levels and CC expression of PTGS2 and HAS2 suggest an association with a better follicle quality. In addition, our data suggest that late follicular phase r-LH supplementation leads to a more advanced stage of follicular maturation.
Progesterone has rapid positive feedback actions on LH release but fails to reduce LH pulse frequency within 12 h in estradiol‐pretreated women
In women, progesterone suppresses luteinizing hormone (LH) (gonadotropin‐releasing hormone) pulse frequency, but how rapidly this occurs is unknown. In estradiol‐pretreated women in the late follicular phase, progesterone administration at 1800 did not slow sleep‐associated LH pulse frequency. However, mechanisms controlling LH pulse frequency may differ according to sleep status; and we thus hypothesized that progesterone acutely suppresses waking LH pulse frequency. This was a randomized, double‐blind, crossover study of LH secretory responses to progesterone versus placebo administered at 0600. We studied 12 normal women in the late follicular phase (cycle days 7–11), pretreated with 3 days of transdermal estradiol (0.2 mg/day). Subjects underwent a 24‐h blood sampling protocol (starting at 2000) and received either 100 mg oral micronized progesterone or placebo at 0600. In a subsequent menstrual cycle, subjects underwent an identical protocol except that oral progesterone was exchanged for placebo or vice versa. Changes in 10‐h LH pulse frequency were similar between progesterone and placebo. However, mean LH, LH pulse amplitude, and mean follicle‐stimulating hormone exhibited significantly greater increases with progesterone. Compared to our previous study (progesterone administered at 1800), progesterone administration at 0600 was associated with a similar increase in mean LH, but a less pronounced increase in LH pulse amplitude. We conclude that, in estradiol‐pretreated women in the late follicular phase, a single dose of progesterone does not suppress waking LH pulse frequency within 12 h, but it acutely amplifies mean LH and LH pulse amplitude – an effect that may be influenced by sleep status and/or time of day. In estradiol‐pretreated women in the late follicular phase, a single dose of progesterone did not inhibit LH pulse frequency within 10 h. However, progesterone acutely amplified mean LH, LH pulse amplitude, and mean FSH. Compared to an earlier study in which progesterone was administered at 1800, progesterone administration at 0600 was associated with a less pronounced increase in LH pulse amplitude, suggesting that the positive feedback effect of progesterone may be influenced by sleep status and/or time of day.
Efficacy and Safety of Domestic Leuprorelin in Girls with Idiopathic Central Precocious Puberty: A Multicenter,Randomized, Parallel, Controlled Trial
Background:In central precocious puberty (CPP),the pulse secretion and release ofgonadotropin-releasing hormone (GnRH) are increased due to early activation of the hypothalamic-pituitary-gonadal axis,resulting in developmental abnormalities with gonadal development and appearance of secondary sexual characteristics.The CPP without organic disease is known as idiopathic CPP (ICPP).The objective of the study was to evaluate the clinical efficacy and safety of domestic leuprorelin (GnRH analog) in girls with ICPP.Methods:A total of 236 girls with ICPP diagnosed from April 2012 to January 2014 were selected and were randomized into two groups.One hundred fifty-seven girls in the test group were treated with domestic leuprorelin acetate,79 girls in the control group were treated with imported leuprorelin acetate.They all were treated and observed for 6 months.After 6-month treatment,the percentage of children with peak luteinizing hormone (LH) ≤3.3 U/L,the percentage of children with peak LH/peak follicle stimulating hormone (FSH) ratio 〈0.6,the improvements of secondary sexual characteristics,gonadal development and sex hormone levels,the change of growth rate of bone age (BA) and growth velocity,and drug adverse effects between two groups were compared.Results:After the treatment,the percentage of children with a suppressed LH response to GnRH,defined as a peak LH ≤3.3 U/L,at 6 months in test and control groups were 96.80% and 96.20%,respectively,and the percentage of children with peak LH/FSH ratio ≤0.6 at 6 months in test and control groups were 93.60% and 93.70%,respectively.The sizes of breast,uterus and ovary of children and the levels of estradiol (E2) were significantly reduced,and the growth rate of BA was also reduced.All the differences between pre-and post-treatment in each group were statistically significant (P 〈 0.05),but the differences of the parameters between two groups were not significant (P 〉 0.05).Conclusions:Domestic leuprorelin is effective and safe in the treatment of Chinese girls with ICPP.Its effectiveness and safety are comparable with imported leuprorelin.
Progesterone administration does not acutely alter LH pulse secretion in the mid‐follicular phase in women
It remains unclear how rapidly progesterone suppresses luteinizing hormone (LH) pulse frequency in women. Previous studies suggested that progesterone markedly increases LH pulse amplitude but does not slow LH pulse frequency within 10 h in estradiol‐pretreated women studied during the late follicular phase. However, this experimental paradigm may be a model of preovulatory physiology, and progesterone may have different effects at other times of the cycle. We studied regularly cycling, nonobese women without hyperandrogenism to assess the acute effect of progesterone during the midfollicular phase and in the absence of estradiol pretreatment. The study involved two admissions in separate cycles (cycle days 5–9). For each admission, either oral micronized progesterone (100 mg) or placebo was administered at 0900 h in a randomized, double‐blind fashion. Frequent blood sampling was performed between 0900 and 1900 h to define 10‐h LH pulsatility. Treatment crossover (placebo exchanged for progesterone and vice versa) occurred in a subsequent cycle. After an interim futility analysis, the study was halted after 7 women completed study. Mean progesterone concentrations after placebo and progesterone administration were 0.5 ± 0.1 (mean ± SD) and 6.7 ± 1.6 ng/mL, respectively. Compared to placebo, progesterone was not associated with a significant difference in 10‐h LH pulse frequency (0.79 ± 0.35 vs. 0.77 ± 0.28 pulses/h, P = 1.0) or amplitude (3.6 ± 2.8 vs. 4.3 ± 2.8 IU/L, P = 0.30). This study suggests that LH pulse frequency is not rapidly influenced by progesterone administration during the midfollicular phase. The rapidity with which progesterone suppresses LH (GnRH) pulse frequency in women is unclear. This study, which was performed in women in the midfollicular phase, adds to available data suggesting that progesterone does not suppress LH (GnRH) pulse frequency within 10 h.
Reproductive effects of subchronic exposure to acetamiprid in male rats
Acetamiprid, a selective agonist of nicotinic acetylcholine recetors, is one of the most widely used neonicotinoids. There is limited data about toxicity of acetamiprid on male reproductive system. Therefore, the study aimed to investigate the reproductive toxic potential of acetamiprid in male rats orally treated with acetamiprid with low (12.5 mg/kg) medium (25 mg/kg) or high dose (35 mg/kg) for 90 days. According to our results, sperm concentration and plasma testosterone levels decreased in dose dependent manner. Gonadotropin-releasing hormone (GnRH), follicle-stimulating hormeone (FSH), luteinizing hormone (LH) levels increased at low and medium dose groups and acetamiprid caused lipid peroxidation and glutathione (GSH) depletion in the testes. Histologic examinations revealed that acetamiprid induced apoptosis in medium and high dose groups and proliferation index dramatically decreased in high dose group. In conclusion, acetamiprid caused toxicity on male reproductive system in the high dose. The mechanism of the toxic effect may be associated with oxidative stress, hormonal disruptions and apoptosis.
The Effect of 2.45 GHz Radiofrequency Electromagnetic Radiation on Components of the Hypothalamic–Pituitary–Gonadal Axis in Male Rats
The brain and testes are connected via the hypothalamic–pituitary–gonadal (HPG) axis. Both are vulnerable to radiofrequency electromagnetic radiation (RF-EMR). However, no comprehensive study had evaluated the effects of RF-EMR on key hormones along this axis. Hereby, this study evaluated the effect of RF-EMR on the hormonal changes along the axis, including the neuropeptide kisspeptin. A total of 18 (N = 18) adult Sprague–Dawley rats were divided into three groups (n = 6): Control, 4 h, and 24 h. The Control group was sham-exposed to an inactive router. The exposed groups were subjected to 2.45 GHz RF-EMR for 4 and 24 h daily, for 60 days at a 20 cm distance. The power density was 0.141 W/m2 with a whole-body specific absorption rate (SAR) of 0.41 W/kg. No significant changes were observed in hypothalamic Kiss1 gene expression or serum kisspeptin levels. GnRH levels increased significantly in both exposed groups, while FSH and LH remained unchanged. Testicular testosterone was significantly reduced in the 24 h group, while serum testosterone was elevated in the 24 h group compared to the 4 h group. In conclusion, prolonged 2.45 GHz RF-EMR exposure caused selective changes in components of the HPG axis, particularly involving GnRH and testosterone, suggesting potential endocrine effects on male reproductive regulation.
Development and Validation of Clinical Diagnostic Model for Girls with Central Precocious Puberty: Machine-learning Approaches
A brief gonadotropin-releasing hormone analogues (GnRHa) stimulation test which solely focused on LH 30-minute post-stimulation was considered to identify girls with central precocious puberty (CPP). However, it was tested using traditional statistical methods. With advanced computer science, we aimed to develop a machine learning-based diagnostic model that processed baseline CPP-related variables and a brief GnRHa stimulation test for CPP diagnosis. We recruited girls suspected of precocious puberty and underwent a GnRHa stimulation test at Children Hospital 2, Vietnam, and Cathay General Hospital, Taiwan. Clinical data, bone age measurement, and 30-min post-stimulation blood test were used to build up the predictive model. The candidate model was developed by different machine learning algorithms that were mainly evaluated by sensitivity, specificity, the area under the receiver operator characteristic curve (AUC), and F1-score in internal and external validation data to classify girls as CPP and non-CPP at different time-points (0-min, 30-min, 60-min, and 120-min post-stimulation). Among the 614 girls diagnosed with PP, 524 (85.3%) had CPP. The random forest algorithm yielded the highest value of F1-score (0.976), specificity (0.893), positive predicted value (0.987), and relatively high value of AUC (0.972) that contributed to high probability to identify CPP. The performance metrics of the 30-min post-stimulation diagnostic model including sensitivity and specificity surpassed those of the 0-minute model (0-min) and were equivalent to those of the model obtained 60-min and 120-min post-stimulation. Hence, our machine learning-based model helps shorten the stimulation test to 30 minutes after GnRHa injection, in general, it requires 120 minutes for a completed GnRHa stimulation test. We developed a diagnostic model based on clinical features and a single sample 30-minute post-stimulation to identify CPP in girls that can reduce distress for children caused by multiple blood samplings.