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1.
Lancet ; 403(10443): 2489-2503, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38782004

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility. Obesity exacerbates the reproductive complications of PCOS; however, the management of obesity in women with PCOS remains a large unmet clinical need. Observational studies have indicated that bariatric surgery could improve the rates of ovulatory cycles and prospects of fertility; however, the efficacy of surgery on ovulation rates has not yet been compared with behavioural modifications and medical therapy in a randomised trial. The aim of this study was to compare the safety and efficacy of bariatric surgery versus medical care on ovulation rates in women with PCOS, obesity, and oligomenorrhoea or amenorrhoea. METHODS: In this multicentre, open-label, randomised controlled trial, 80 women older than 18 years, with a diagnosis of PCOS based on the 2018 international evidence-based guidelines for assessing and managing PCOS, and a BMI of 35 kg/m2 or higher, were recruited from two specialist obesity management centres and via social media. Participants were randomly assigned at a 1:1 ratio to either vertical sleeve gastrectomy or behavioural interventions and medical therapy using a computer-generated random sequence (PLAN procedure in SAS) by an independent researcher not involved with any other aspect of the clinical trial. The median age of the entire cohort was 31 years and 79% of participants were White. The primary outcome was the number of biochemically confirmed ovulatory events over 52 weeks, and was assessed using weekly serum progesterone measurements. The primary endpoint included the intention-to-treat population and safety analyses were per-protocol population. This study is registered with the ISRCTN registry (ISRCTN16668711). FINDINGS: Participants were recruited from Feb 20, 2020 to Feb 1, 2021. 40 participants were assigned to each group and there were seven dropouts in the medical group and ten dropouts in the surgical group. The median number of ovulations was 6 (IQR 3·5-10·0) in the surgical group and 2 (0·0-4·0) in the medical group. Women in the surgical group had 2.5 times more spontaneous ovulations compared with the medical group (incidence rate ratio 2·5 [95% CI 1·5-4·2], p<0·0007). There were more complications in the surgical group than the medical group, although without long-term sequelae. There were 24 (66·7%) adverse events in the surgical group and 12 (30·0%) in the medical group. There were no treatment-related deaths. INTERPRETATION: Bariatric surgery was more effective than medical care for the induction of spontaneous ovulation in women with PCOS, obesity, and oligomenorrhoea or amenorrhoea. Bariatric surgery could, therefore, enhance the prospects of spontaneous fertility in this group of women. FUNDING: The Jon Moulton Charity Trust.


Assuntos
Cirurgia Bariátrica , Obesidade , Ovulação , Síndrome do Ovário Policístico , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/cirurgia , Feminino , Adulto , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Obesidade/complicações , Obesidade/cirurgia , Oligomenorreia , Resultado do Tratamento , Amenorreia/etiologia , Adulto Jovem , Gastrectomia/métodos , Gastrectomia/efeitos adversos , Infertilidade Feminina/etiologia
2.
PLoS Comput Biol ; 20(2): e1011928, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38422116

RESUMO

The hypothalamus is the central regulator of reproductive hormone secretion. Pulsatile secretion of gonadotropin releasing hormone (GnRH) is fundamental to physiological stimulation of the pituitary gland to release luteinizing hormone (LH) and follicle stimulating hormone (FSH). Furthermore, GnRH pulsatility is altered in common reproductive disorders such as polycystic ovary syndrome (PCOS) and hypothalamic amenorrhea (HA). LH is measured routinely in clinical practice using an automated chemiluminescent immunoassay method and is the gold standard surrogate marker of GnRH. LH can be measured at frequent intervals (e.g., 10 minutely) to assess GnRH/LH pulsatility. However, this is rarely done in clinical practice because it is resource intensive, and there is no open-access, graphical interface software for computational analysis of the LH data available to clinicians. Here we present hormoneBayes, a novel open-access Bayesian framework that can be easily applied to reliably analyze serial LH measurements to assess LH pulsatility. The framework utilizes parsimonious models to simulate hypothalamic signals that drive LH dynamics, together with state-of-the-art (sequential) Monte-Carlo methods to infer key parameters and latent hypothalamic dynamics. We show that this method provides estimates for key pulse parameters including inter-pulse interval, secretion and clearance rates and identifies LH pulses in line with the widely used deconvolution method. We show that these parameters can distinguish LH pulsatility in different clinical contexts including in reproductive health and disease in men and women (e.g., healthy men, healthy women before and after menopause, women with HA or PCOS). A further advantage of hormoneBayes is that our mathematical approach provides a quantified estimation of uncertainty. Our framework will complement methods enabling real-time in-vivo hormone monitoring and therefore has the potential to assist translation of personalized, data-driven, clinical care of patients presenting with conditions of reproductive hormone dysfunction.


Assuntos
Hormônio Liberador de Gonadotropina , Hormônio Luteinizante , Masculino , Feminino , Humanos , Teorema de Bayes , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Foliculoestimulante , Hipotálamo/metabolismo
3.
Clin Endocrinol (Oxf) ; 100(5): 459-465, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38420872

RESUMO

OBJECTIVE: Polycystic ovary syndrome (PCOS) is a chronic lifelong condition affecting up to 20% of women worldwide. There is limited input from affected women to guide the provision of healthcare services and future research needs. Our objective was to scope the healthcare and research priorities of women with PCOS in the United Kingdom. DESIGN: A three-staged modified Delphi method, consisting of two questionnaires and a consensus meeting involving lay representatives and healthcare professionals. PATIENTS AND MEASUREMENTS: Lay patient representatives of women with PCOS. Participants were asked to identify and rank healthcare and research priorities for their importance. RESULTS: Six hundred and twenty-four lay participants took part in our Delphi method. Over 98% were diagnosed with PCOS (614/624, 98.4%). More than half experienced difficulties to receive a PCOS diagnosis (375/624, 60%), and the majority found it difficult to access specialised PCOS health services in the NHS (594/624, 95%). The top two healthcare priorities included better education for health professionals on the diagnosis and management of PCOS (238/273, 87.1%) and the need to set up specialist PCOS services (234/273, 85.7%). The top two research priorities focused on identifying better treatments for irregular periods (233/273, 85.3%) followed by better tests for early PCOS diagnosis (230/273, 84.2%). CONCLUSIONS: We identified 13 healthcare and 14 research priorities that reflect the current health needs of women with PCOS in the United Kingdom. Adopting these priorities in future healthcare and research planning will help to optimise the health of women with PCOS and increase patient satisfaction.


Assuntos
Síndrome do Ovário Policístico , Humanos , Feminino , Síndrome do Ovário Policístico/terapia , Síndrome do Ovário Policístico/diagnóstico , Medicina Estatal , Técnica Delphi , Pesquisa , Atenção à Saúde
4.
Clin Sci (Lond) ; 137(11): 863-879, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37272254

RESUMO

Reproductive conditions secondary to disorders of the hypothalamic-pituitary-gonadal (HPG) axis are common and are associated with important health implications and considerable psychosocial impact. Basal and dynamic tests enable interrogation of individual components of the HPG axis, facilitating diagnosis and understanding of the pathophysiology of reproductive disorders. Onset of puberty is controlled by hypothalamic gonadotrophin-releasing hormone (GnRH) neuronal function. To date, a dynamic test of hypothalamic function is not yet available. Therefore, accurate differentiation of pubertal disorders such as constitutional delay of growth and puberty (CDGP) and congenital hypogonadotrophic hypogonadism (CHH) as causes of delayed puberty is challenging due to similar clinical presentations and hormonal profiles. Likewise, although the two commonest reproductive disorders in women, polycystic ovary syndrome (PCOS) and functional hypothalamic amenorrhoea (FHA) have disparate hypothalamic function, oligo/amenorrhoea frequently poses a diagnostic conundrum owing to the overlap in the criteria used to define both conditions. This review aims to describe pubertal and reproductive disorders secondary to pathologies affecting the HPG axis. Challenges encountered in clinical practice in differentiating pubertal and reproductive conditions are reviewed in conjunction with the utility of baseline and dynamic endocrine tests to interrogate specific components of the HPG axis. We also highlight putative hypothalamic, pituitary, and gonadal markers in development that could improve the diagnosis of patients presenting with disorders of puberty or reproduction.


Assuntos
Amenorreia , Hipogonadismo , Humanos , Feminino , Reprodução/fisiologia , Hormônio Liberador de Gonadotropina , Gônadas , Hipogonadismo/diagnóstico
5.
Clin Endocrinol (Oxf) ; 97(2): 156-164, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35262967

RESUMO

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age and is the leading cause of anovulatory subfertility. Increased gonadotrophin releasing hormone (GnRH) pulsatility in the hypothalamus results in preferential luteinizing hormone (LH) secretion from the pituitary gland, leading to ovarian hyperandrogenism and oligo/anovulation. The resultant hyperandrogenism reduces negative feedback from sex steroids such as oestradiol and progesterone to the hypothalamus, and thus perpetuates the increase in GnRH pulsatility. GnRH neurons do not have receptors for oestrogen, progesterone, or androgens, and thus the disrupted feedback is hypothesized to occur via upstream neurons. Likely candidates for these upstream regulators of GnRH neuronal pulsatility are Kisspeptin, Neurokinin B (NKB), and Dynorphin neurons (termed KNDy neurons). Growing insight into the neuroendocrine dysfunction underpinning the heightened GnRH pulsatility seen in PCOS has led to research on the use of pharmaceutical agents that specifically target the activity of these KNDy neurons to attenuate symptoms of PCOS. This review aims to highlight the neuroendocrine abnormalities that lead to increased GnRH pulsatility in PCOS, and outline data on recent therapeutic advancements that could potentially be used to treat PCOS. Emerging evidence has investigated the use of neurokinin 3 receptor (NK3R) antagonists as a method of reducing GnRH pulsatility and alleviating features of PCOS such as hyperandrogenism. We also consider other potential mechanisms by which increased GnRH pulsatility is controlled, which could form the basis of future avenues of research.


Assuntos
Hiperandrogenismo , Síndrome do Ovário Policístico , Feminino , Hormônio Liberador de Gonadotropina , Humanos , Hiperandrogenismo/tratamento farmacológico , Kisspeptinas , Hormônio Luteinizante , Síndrome do Ovário Policístico/tratamento farmacológico , Progesterona
6.
Clin Endocrinol (Oxf) ; 95(2): 239-252, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33354766

RESUMO

BACKGROUND: Secondary oligo/amenorrhoea occurs in 3%-5% of women of reproductive age. The two most common causes are polycystic ovary syndrome (PCOS) (2%-13%) and functional hypothalamic amenorrhoea (FHA) (1%-2%). Whilst both conditions have distinct pathophysiology and their diagnosis is supported by guidelines, in practice, differentiating these two common causes of menstrual disturbance is challenging. Moreover, both diagnoses are qualified by the need to first exclude other causes of menstrual disturbance. AIM: To review clinical, biochemical and radiological parameters that could aid the clinician in distinguishing PCOS and FHA as a cause of menstrual disturbance. RESULTS: FHA is uncommon in women with BMI > 24 kg/m2 , whereas both PCOS and FHA can occur in women with lower BMIs. AMH levels are markedly elevated in PCOS; however, milder increases may also be observed in FHA. Likewise, polycystic ovarian morphology (PCOM) is more frequently observed in FHA than in healthy women. Features that are differentially altered between PCOS and FHA include LH, androgen, insulin, AMH and SHBG levels, endometrial thickness and cortisol response to CRH. Other promising diagnostic tests with the potential to distinguish these two conditions pending further study include assessment of 5-alpha-reductase activity, leptin, INSL3, kisspeptin and inhibin B levels. CONCLUSION: Further data directly comparing the discriminatory potential of these markers to differentiate PCOS and FHA in women with secondary amenorrhoea would be of value in defining an objective probability for PCOS or FHA diagnosis.


Assuntos
Síndrome do Ovário Policístico , Amenorreia/diagnóstico , Androgênios , Hormônio Antimülleriano , Feminino , Humanos , Distúrbios Menstruais , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/diagnóstico
7.
Clin Endocrinol (Oxf) ; 95(4): 618-627, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323305

RESUMO

OBJECTIVES: Functional hypothalamic amenorrhoea (FHA) is a common cause of amenorrhoea, but diagnosis can be challenging. The aim of this study was to investigate the clinical and biochemical features of FHA, compared to that of polycystic ovarian syndrome (PCOS) and assess the diagnostic performance of the different parameters for differentiating the two conditions. DESIGN AND PATIENTS: This was a retrospective observational study. We analysed clinical and biochemical parameters of women diagnosed with FHA and PCOS following specialist assessment at the reproductive endocrine gynaecology clinic, St Mary's Hospital. RESULTS: Compared with PCOS, women with FHA had significantly lower body mass index (BMI; 20.1 ± 2.9 vs. 31.1 ± 7.8 kg/m2 ; p< .0001) and a thinner endometrium (3.75 ± 2.23 vs. 6.82 ± 3.32 mm; p< .0001). Women with FHA had significantly lower luteinising hormone (LH; 3.46 ± 7.31 vs. 8.79 ± 4.98 IU/L; p< .0001), and lower LH to follicle-stimulating hormone (FSH) ratio, estradiol, thyroid-stimulating hormone, free thyroxine and prolactin levels; there was no significant difference in FSH levels. BMI had the greatest predictive performance for FHA (area under the curve [AUC]: 0.93; p< .001), followed by estradiol (AUC: 0.89; p< .001), LH (AUC: 0.88; p< .001) and LH:FSH ratio (AUC: 0.86; p< .001). CONCLUSIONS: Our data provides quantification for diagnostic accuracy of clinical parameters to differentiate FHA from PCOS, namely low BMI, estradiol, LH and LH:FSH ratio. These data could help clinicians more reliably diagnose FHA in women with secondary amenorrhoea.


Assuntos
Síndrome do Ovário Policístico , Amenorreia/diagnóstico , Biomarcadores , Feminino , Hormônio Foliculoestimulante , Humanos , Hormônio Luteinizante , Síndrome do Ovário Policístico/diagnóstico
8.
Neuroendocrinology ; 111(12): 1176-1186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33227799

RESUMO

BACKGROUND: Hypogonadotropic hypogonadism (HH) is hypogonadism due to either hypothalamic or pituitary dysfunction. While gonadotropin-releasing hormone (GnRH) can directly test pituitary function, no specific test of hypothalamic function exists. Kisspeptin-54 (KP54) is a neuropeptide that directly stimulates hypothalamic GnRH release and thus could be used to specifically interrogate hypothalamic function. Congenital HH (CHH) is typically due to variants in genes that control hypothalamic GnRH neuronal migration or function. Thus, we investigated whether KP54 could accurately identify hypothalamic dysfunction in men with CHH. METHODS: Men with CHH (n = 21) and healthy eugonadal men (n = 21) received an intravenous bolus of either GnRH (100 µg) or KP54 (6.4 nmol/kg), on 2 occasions, and were monitored for 6 h after administration of each neuropeptide. RESULTS: Maximal luteinizing hormone (LH) rise after KP54 was significantly greater in healthy men (12.5 iU/L) than in men with CHH (0.4 iU/L; p < 0.0001). KP54 more accurately differentiated CHH men from healthy men than GnRH (area under receiver operating characteristic curve KP54: 1.0, 95% CI 1.0-1.0; GnRH: 0.88, 95% CI 0.76-0.99). Indeed, all CHH men had an LH rise <2.0 iU/L following KP54, whereas all healthy men had an LH rise >4.0 iU/L. Anosmic men with CHH (i.e., Kallmann syndrome) had even lower LH rises after KP54 than did normosmic men with CHH (p = 0.017). Likewise, men identified to have pathogenic/likely pathogenic variants in CHH genes had even lower LH rises after KP54 than other men with CHH (p = 0.035). CONCLUSION: KP54 fully discriminated men with CHH from healthy men. Thus, KP54 could be used to specifically interrogate hypothalamic GnRH neuronal function in patients with CHH.


Assuntos
Hormônio Liberador de Gonadotropina/farmacologia , Hipogonadismo/sangue , Hipogonadismo/congênito , Hipogonadismo/diagnóstico , Kisspeptinas/farmacologia , Hormônio Luteinizante/sangue , Hormônio Luteinizante/efeitos dos fármacos , Adulto , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Síndrome de Kallmann/sangue , Síndrome de Kallmann/diagnóstico , Kisspeptinas/administração & dosagem , Masculino
9.
Clin Endocrinol (Oxf) ; 93(3): 312-321, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32362009

RESUMO

BACKGROUND: There are no current pharmacological therapies to improve sperm quality in men with sub-fertility. Reducing the exposure to lifestyle risk factor (LSF) is currently the only intervention for improving sperm quality in men with sub-fertility. No previous study has investigated what proportion of men with sub-fertility are exposed to adverse lifestyle factors. Furthermore, it is not known to what extent men with sub-fertility are aware of lifestyle factors potentially adversely impacting their fertility. METHODS: A cross-sectional anonymous questionnaire-based study on self-reported exposure and awareness of LSF was conducted in 1149 male partners of couples investigated for sub-fertility in a tertiary andrology centre in London, UK. RESULTS: Seventy per cent of men investigated for sub-fertility had ≥1 LSF, and twenty-nine per cent had ≥2 LSF. Excessive alcohol consumption was the most common LSF (40% respondents). Seventeen per cent of respondents used recreational drugs (RD) regularly, but only 32% of RD users believed RD impair male fertility. Twenty-five per cent of respondents were smokers, which is higher than the UK average (20%). Twenty-seven per cent of respondents had a waist circumference (WC) >36 inches (91 cm), and 4% had WC >40 inches (102 cm). Seventy-nine per cent of respondents wanted further lifestyle education to improve their fertility. CONCLUSIONS: Our data suggest that men with sub-fertility are as follows: (a) exposed to one or more LSF; (b) have incomplete education about how LSF may cause male sub-fertility; (c) want more education about reducing LSF. Further studies are needed to investigate the potential of enhanced education of men about LSF to treat couples with sub-fertility.


Assuntos
Infertilidade Masculina , Análise do Sêmen , Estudos Transversais , Humanos , Estilo de Vida , Masculino , Autorrelato
10.
Int J Mol Sci ; 21(19)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036411

RESUMO

Aptamers are a novel technology enabling the continuous measurement of analytes in blood and other body compartments, without the need for repeated sampling and the associated reagent costs of traditional antibody-based methodologies. Aptamers are short single-stranded synthetic RNA or DNA that recognise and bind to specific targets. The conformational changes that can occur upon aptamer-ligand binding are transformed into chemical, fluorescent, colour changes and other readouts. Aptamers have been developed to detect and measure a variety of targets in vitro and in vivo. Gonadotropin-releasing hormone (GnRH) is a pulsatile hypothalamic hormone that is essential for normal fertility but difficult to measure in the peripheral circulation. However, pulsatile GnRH release results in pulsatile luteinizing hormone (LH) release from the pituitary gland. As such, LH pulsatility is the clinical gold standard method to determine GnRH pulsatility in humans. Aptamers have recently been shown to successfully bind to and measure GnRH and LH, and this review will focus on this specific area. However, due to the adaptability of aptamers, and their suitability for incorporation into portable devices, aptamer-based technology is likely to be used more widely in the future.


Assuntos
Aptâmeros de Nucleotídeos , Bioensaio/métodos , Hormônio Liberador de Gonadotropina/sangue , Hormônio Luteinizante/sangue , Animais , Biomarcadores , Feminino , Humanos , Técnicas de Diagnóstico Molecular , Técnica de Seleção de Aptâmeros , Fatores de Tempo
11.
Am J Obstet Gynecol ; 220(5): 480.e1-480.e17, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30707968

RESUMO

BACKGROUND: Ectopic pregnancy is a life-threatening condition for which novel screening tools that would enable early accurate diagnosis would improve clinical outcomes. Kisspeptins, encoded by KISS1, play an essential role in human reproduction, at least partially by regulating placental function and possibly embryo implantation. Kisspeptin levels are elevated massively in normal pregnancy and reportedly altered in various gestational pathologic diseases. Yet, the pathophysiologic role of KISS1/kisspeptin in ectopic pregnancy has not been investigated previously. OBJECTIVE: The purpose of this study was to evaluate changes of KISS1/kisspeptin levels in ectopic pregnancy and their underlaying molecular mechanisms and to ascertain the diagnostic implications of these changes. STUDY DESIGN: A total of 122 women with normal pregnancy who underwent voluntary termination of pregnancy and 84 patients who experienced tubal ectopic pregnancy were recruited. Measurements of plasma kisspeptins and KISS1 expression analyses in human embryonic/placental tissue were conducted in ectopic pregnancy and voluntary termination of pregnancy control subjects during the early gestational window (<12 weeks). Putative microRNA regulators of KISS1 were predicted in silico, followed by expression analyses of selected microRNAs and validation of repressive interactions in vitro. Circulating levels of these microRNAs were also assayed in ectopic pregnancy vs voluntary termination of pregnancy. RESULTS: Circulating kisspeptins gradually increased during the first trimester of normal pregnancy but were reduced markedly in ectopic pregnancy. This profile correlated with the expression levels of KISS1 in human embryonic/placental tissue, which increased in voluntary termination of pregnancy but remained suppressed in ectopic pregnancy. Bioinformatic predictions and expression analyses identified miR-27b-3p and miR-324-3p as putative repressors of KISS1 in human embryonic/placental tissue at <12 weeks gestation, when expression of microRNAs was low in voluntary termination of pregnancy control subjects but significantly increased in ectopic pregnancy. Yet, a significant repressive interaction was documented only for miR-324-3p, occurring at the predicted 3'-UTR of KISS1. Interestingly, circulating levels of miR-324-3p, but not of miR-27b-3p, were suppressed distinctly in ectopic pregnancy, despite elevated tissue expression of the pre-microRNA. A decision-tree model that used kisspeptin and miR-324-3p levels was successful in discriminating ectopic pregnancy vs voluntary termination of pregnancy, with a receiver-operating characteristic area under the curve of 0.95±0.02 (95% confidence interval). CONCLUSION: Our results document a significant down-regulation of KISS1/kisspeptins in early stages of ectopic pregnancy via, at least partially, a repressive interaction with miR-324-3p. Our data identify circulating kisspeptins and miR-324-3p as putative biomarkers for accurate screening of ectopic pregnancy at early gestational ages.


Assuntos
Embrião de Mamíferos/metabolismo , Kisspeptinas/metabolismo , MicroRNAs/metabolismo , Placenta/metabolismo , Gravidez Ectópica/diagnóstico , Biomarcadores/metabolismo , Estudos de Casos e Controles , Árvores de Decisões , Regulação para Baixo , Diagnóstico Precoce , Feminino , Idade Gestacional , Humanos , Kisspeptinas/genética , Gravidez , Gravidez Ectópica/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
13.
Neuroendocrinology ; 106(4): 401-410, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29544222

RESUMO

BACKGROUND: Male testosterone levels decline by 1% per year from the age of 40 years. Whilst a primary testicular deficit occurs, hypothalamic or pituitary dysregulation may also coexist. This study aimed to compare the hypothalamic response to kisspeptin-54 and the pituitary response to gonadotropin-releasing hormone (GnRH) of older men with those of young men. METHODS: Following 1 h of baseline sampling, healthy older men (n = 5, mean age 59.3 ± 2.9 years) received a 3-h intravenous infusion of either vehicle, kisspeptin-54 0.1, 0.3, or 1.0 nmol/kg/h or GnRH 0.1 nmol/kg/h, on five different study days. Serum gonadotropins and total testosterone were measured every 10 min and compared to those of young men (n = 5/group) (mean age 28.9 ± 2.0 years) with a similar body mass index (24 kg/m2) who underwent the same protocol. RESULTS: Kisspeptin-54 and GnRH significantly stimulated serum gonadotropin release in older men compared to vehicle (p < 0.001 for all groups). Gonadotropin response to kisspeptin-54 was at least preserved in older men when compared to young men. At the highest dose of kisspeptin-54 (1.0 nmol/kg/h), a significantly greater luteinising hormone (LH) (p = 0.003) response was observed in older men. The follicle-stimulating hormone (FSH) response to GnRH was increased in older men (p = 0.002), but the LH response was similar (p = 0.38). Serum testosterone rises following all doses of kisspeptin-54 (p ≤ 0.009) were reduced in older men. CONCLUSIONS: Our data suggest that healthy older men without late-onset hypo-gonadism (LOH) have preserved hypothalamic response to kisspeptin-54 and pituitary response to GnRH, but impaired testicular response. Further work is required to investigate the use of kisspeptin-54 to identify hypothalamic deficits in men with LOH.


Assuntos
Envelhecimento/metabolismo , Gonadotropinas/sangue , Hipotálamo/metabolismo , Hipófise/inervação , Testosterona/sangue , Adulto , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Hipotálamo/efeitos dos fármacos , Kisspeptinas/farmacologia , Masculino , Pessoa de Meia-Idade , Hipófise/efeitos dos fármacos , Hipófise/metabolismo
14.
Neuroendocrinology ; 107(2): 105-113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29660734

RESUMO

BACKGROUND/AIMS: Hyperprolactinaemia is a common cause of amenorrhoea due to hypogonadotropic hypogonadism. Prolactin is hypothesised to impede the reproductive axis through an inhibitory action at the hypothalamus. However, limited data exist to aid the interpretation of serum gonadotropins in the context of hyperprolactinaemia. METHODS: Serum gonadotropin values were reviewed in 243 patients with elevated serum monomeric prolactin due to discrete aetiologies at a tertiary reproductive endocrine centre between 2012 and 2015. The cause of hyperprolactinaemia was categorised by an experienced endocrinologist/pituitary multidisciplinary team, unless superseded by histology. The most frequently encountered diagnoses were microprolactinoma (n = 88), macroprolactinoma (n = 46), non-functioning pituitary adenoma (NFPA) (n = 72), drug-induced hyperprolactinaemia (n = 22) and polycystic ovarian syndrome (PCOS) (n = 15). RESULTS: In patients with prolactinoma and modestly raised serum prolactin levels (< 4,000 mU/L), increasingly FSH-predominant gonadotropin values were observed with rising prolactin level, consistent with a progressive reduction in hypothalamic gonadotropin-releasing hormone (GnRH) pulsatility. Patients with prolactinoma and higher prolactin values (> 4,000 mU/L) were more likely to have a reduction in serum levels of both FSH and LH, consistent with direct pituitary gonadotrope dysfunction. Patients with macroadenoma and extremes of serum gonadotropin values (either serum FSH or LH > 8 IU/L) were more likely to have NFPA than prolactinoma. Patients with PCOS and hyperprolactinaemia had LH-predominant secretion in keeping with increased GnRH pulsatility despite a raised prolactin level. CONCLUSION: The pattern of gonadotropin secretion in patients with hyperprolactinaemia reflects the underlying aetiology.


Assuntos
Gonadotropinas/sangue , Hiperprolactinemia/sangue , Hiperprolactinemia/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Diabetes Obes Metab ; 20(12): 2800-2810, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29974637

RESUMO

AIMS: To investigate the effect of kisspeptin on glucose-stimulated insulin secretion and appetite in humans. MATERIALS AND METHODS: In 15 healthy men (age: 25.2 ± 1.1 years; BMI: 22.3 ± 0.5 kg m-2 ), we compared the effects of 1 nmol kg-1 h-1 kisspeptin versus vehicle administration on glucose-stimulated insulin secretion, metabolites, gut hormones, appetite and food intake. In addition, we assessed the effect of kisspeptin on glucose-stimulated insulin secretion in vitro in human pancreatic islets and a human ß-cell line (EndoC-ßH1 cells). RESULTS: Kisspeptin administration to healthy men enhanced insulin secretion following an intravenous glucose load, and modulated serum metabolites. In keeping with this, kisspeptin increased glucose-stimulated insulin secretion from human islets and a human pancreatic cell line in vitro. In addition, kisspeptin administration did not alter gut hormones, appetite or food intake in healthy men. CONCLUSIONS: Collectively, these data demonstrate for the first time a beneficial role for kisspeptin in insulin secretion in humans in vivo. This has important implications for our understanding of the links between reproduction and metabolism in humans, as well as for the ongoing translational development of kisspeptin-based therapies for reproductive and potentially metabolic conditions.


Assuntos
Apetite/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Kisspeptinas/farmacologia , Adolescente , Adulto , Linhagem Celular , Glucose/metabolismo , Voluntários Saudáveis , Humanos , Insulina/sangue , Masculino , Adulto Jovem
18.
Hum Reprod ; 32(9): 1915-1924, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854728

RESUMO

STUDY QUESTION: Can increasing the duration of LH-exposure with a second dose of kisspeptin-54 improve oocyte maturation in women at high risk of ovarian hyperstimulation syndrome (OHSS)? SUMMARY ANSWER: A second dose of kisspeptin-54 at 10 h following the first improves oocyte yield in women at high risk of OHSS. WHAT IS KNOWN ALREADY: Kisspeptin acts at the hypothalamus to stimulate the release of an endogenous pool of GnRH from the hypothalamus. We have previously reported that a single dose of kisspeptin-54 results in an LH-surge of ~12-14 h duration, which safely triggers oocyte maturation in women at high risk of OHSS. STUDY DESIGN, SIZE, DURATION: Phase-2 randomized placebo-controlled trial of 62 women at high risk of OHSS recruited between August 2015 and May 2016. Following controlled ovarian stimulation, all patients (n = 62) received a subcutaneous injection of kisspeptin-54 (9.6 nmol/kg) 36 h prior to oocyte retrieval. Patients were randomized 1:1 to receive either a second dose of kisspeptin-54 (D; Double, n = 31), or saline (S; Single, n = 31) 10 h thereafter. Patients, embryologists, and IVF clinicians remained blinded to the dosing allocation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Study participants: Sixty-two women aged 18-34 years at high risk of OHSS (antral follicle count ≥23 or anti-Mullerian hormone level ≥40 pmol/L). Setting: Single centre study carried out at Hammersmith Hospital IVF unit, London, UK. Primary outcome: Proportion of patients achieving an oocyte yield (percentage of mature oocytes retrieved from follicles ≥14 mm on morning of first kisspeptin-54 trigger administration) of at least 60%. Secondary outcomes: Reproductive hormone levels, implantation rate and OHSS occurrence. MAIN RESULTS AND THE ROLE OF CHANCE: A second dose of kisspeptin-54 at 10 h following the first induced further LH-secretion at 4 h after administration. A higher proportion of patients achieved an oocyte yield ≥60% following a second dose of kisspeptin-54 (Single: 14/31, 45%, Double: 21/31, 71%; absolute difference +26%, CI 2-50%, P = 0.042). Patients receiving two doses of kisspeptin-54 had a variable LH-response following the second kisspeptin dose, which appeared to be dependent on the LH-response following the first kisspeptin injection. Patients who had a lower LH-rise following the first dose of kisspeptin had a more substantial 'rescue' LH-response following the second dose of kisspeptin. The variable LH-response following the second dose of kisspeptin resulted in a greater proportion of patients achieving an oocyte yield ≥60%, but without also increasing the frequency of ovarian over-response and moderate OHSS (Single: 1/31, 3.2%, Double: 0/31, 0%). LIMITATIONS, REASONS FOR CAUTION: Further studies are warranted to directly compare kisspeptin-54 to more established triggers of oocyte maturation. WIDER IMPLICATIONS OF THE FINDINGS: Triggering final oocyte maturation with kisspeptin is a novel therapeutic option to enable the use of fresh embryo transfer even in the woman at high risk of OHSS. STUDY FUNDING/COMPETING INTEREST(S): The study was designed, conducted, analysed and reported entirely by the authors. The Medical Research Council (MRC), Wellcome Trust & National Institute of Health Research (NIHR) provided research funding to carry out the studies. There are no competing interests to declare. TRIAL REGISTRATION NUMBER: Clinicaltrial.gov identifier NCT01667406. TRIAL REGISTRATION DATE: 8 August 2012. DATE OF FIRST PATIENT'S ENROLMENT: 10 August 2015.


Assuntos
Kisspeptinas/uso terapêutico , Recuperação de Oócitos , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Indução da Ovulação/métodos , Adolescente , Adulto , Método Duplo-Cego , Feminino , Fertilização in vitro/métodos , Humanos , Kisspeptinas/administração & dosagem , Gravidez , Taxa de Gravidez
20.
Clin Endocrinol (Oxf) ; 84(6): 939-45, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26572695

RESUMO

BACKGROUND AND OBJECTIVE: Kisspeptin stimulates hypothalamic GnRH secretion resulting in gonadotrophin release and has potential as a future therapeutic. Chronic subcutaneous infusion of kisspeptin via a pump (similar to an insulin pump) may provide an alternative route of administration in the future. We investigated for the first time in humans, the gonadotrophin response to subcutaneous (SC) infusions of kisspeptin-54 in healthy women. Women are markedly more responsive to exogenous kisspeptin in the late follicular phase preovulation when oestradiol levels are naturally high. Therefore, we further investigated whether there was a correlation between baseline oestradiol levels and LH response to kisspeptin. DESIGN AND PATIENTS: A prospective, single-blinded placebo-controlled study. Healthy women (n = 4) received an 8-h SC infusion of kisspeptin-54 0·1, 0·3 or 1·0 nmol/kg/h or saline in the early follicular phase of 4 separate menstrual cycles. Gonadotrophins and oestradiol were measured every 10 min during the infusions. RESULTS: SC infusion of kisspeptin-54 increased LH and FSH. The LH response to SC infusion of kisspeptin-54 (0·3 and 1·0 nmol/kg/h) positively correlated with baseline oestradiol levels (P < 0·001). Further statistical analyses showed that in the 1·0 nmol/kg/h group, a 100pmol/l rise in baseline oestradiol was associated with a 1·0 IU/l increase in LH. CONCLUSIONS: Kisspeptin administered via a SC infusion could be a viable future therapeutic route of administration for patients with infertility. Baseline oestradiol levels may be an important determinant of the gonadotrophin response to kisspeptin treatment in women and should be taken into consideration when evaluating gonadotrophin response.


Assuntos
Estradiol/sangue , Gonadotropinas/metabolismo , Kisspeptinas/administração & dosagem , Adolescente , Adulto , Feminino , Fase Folicular , Hormônio Liberador de Gonadotropina , Gonadotropinas/sangue , Humanos , Infusões Subcutâneas , Kisspeptinas/farmacologia , Hormônio Luteinizante/sangue , Estudos Prospectivos , Adulto Jovem
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