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1.
Open Vet J ; 14(1): 428-437, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38633156

RESUMO

Background: Obesity is one of the most prevalent and perilous health affairs. Male obesity-associated secondary hypogonadism (MOSH) is one of many of its complexities, which is mounting in parallel with the aggravation of obesity. Magnetic nanoparticles seem to be an advanced favorable trend in multiple biomedical fields. Aim: In this study, we explore the therapeutic effects of superparamagnetic iron oxide nanoparticles (SPIONs) coated with carboxymethyl cellulose (CMC) on an obese male rat model with MOSH syndrome, comparing their impacts with a well-known anti-obesity medication (Orlistat). Methods: 42 male albino rats split into 7 equal groups: 1-negative control: nonobese, untreated; 35 rats fed the high fat-high fructose (HFHF) diet for a period of 12 weeks. Obese rats splitted into 6 equal groups; 2-positive control: obese untreated; 3-obese given Orlistat (30 mg/kg); 4-obese given CMC-SPIONs (25 mgFe/kg); 5-obese given CMC-SPIONs (50 mgFe/kg); 6-obese given CMC-SPIONs(25 mgFe/kg) + Orlistat (30 mg/kg), 7-obese given CMC-SPIONs (50 mgFe/kg) + Orlistat (30 mg/kg); all treatments given orally for 4 weeks. During sacrifice, blood serum and sectioned hypothalamic, pituitary, testicular, and adipose tissues were collected for biochemical and biomolecular assessments. Results: The HFHF diet for 12 weeks resulted in a significant upsurge in body weight, body mass index, serum fasting glucose, insulin resistance, TAG, total cholesterol, and LDL-c; HDL-c was dropped. Serum FSH, LH, and testosterone values declined. A significant disorder in expression levels of genes regulating the hypothalamic-pituitary-testicular-axis pathway. Hypothalamic GnRH, Kisspeptin-1, Kisspeptin-r1, and Adipo-R1 values declined. GnIH and Leptin-R1 values raised up. Pituitary GnRH-R values declined. Testicular tissue STAR, HSD17B3, and CYP19A1 values declined. Adipose tissue adiponectin declined, while leptin raised up. CMC-SPIONs 25-50 mg could modulate the deranged biochemical parameters and correct the deranged expression levels of all previous genes. Co-treatments revealed highly synergistic effects on all parameters. Overall, CMC-SPIONs have significant efficiency whether alone or with Orlisat in limiting obesity and consequence subfertility. Conclusion: CMC-SPIONs act as an incoming promising contender for obesity and MOSH disorders management, and need more studies on their mechanisms.


Assuntos
Hipogonadismo , Obesidade , Doenças dos Roedores , Ratos , Masculino , Animais , Leptina/metabolismo , Leptina/uso terapêutico , Orlistate/metabolismo , Orlistate/farmacologia , Orlistate/uso terapêutico , Testículo/metabolismo , Obesidade/genética , Obesidade/metabolismo , Obesidade/veterinária , Hipogonadismo/metabolismo , Hipogonadismo/veterinária , Hipotálamo/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Liberador de Gonadotropina/uso terapêutico , Nanopartículas Magnéticas de Óxido de Ferro
2.
Sci Rep ; 14(1): 8989, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637687

RESUMO

In mammals reproduction is regulated by many factors, among others by the peptides belonging to the RFamide peptide family. However, the knowledge concerning on the impact of recently identified member of this family (QRFP43) on the modulation of the gonadotrophic axis activity is still not fully understood and current research results are ambiguous. In the present study we tested the in vivo effect of QRFP43 on the secretory activity of the gonadotrophic axis at the hypothalamic-pituitary level in Polish Merino sheep. The animals (n = 48) were randomly divided into three experimental groups: controls receiving an icv infusion of Ringer-Locke solution, group receiving icv infusion of QRFP43 at 10 µg per day and 50 µg per day. All sheep received four 50 min icv infusions at 30 min intervals, on each of three consecutive days. Hypothalamic and pituitaries were collected and secured for further immunohistochemical and molecular biological analysis. In addition, during the experiment a blood samples have been collected for subsequent RIA determinations. QRFP43 was found to downregulate Kiss mRNA expression in the MBH and reduce the level of IR material in ME. This resulted in a reduction of GnRH IR material in the ME. QRFP43 increased plasma FSH levels while decreasing LH levels. Our findings indicate that QRFP43 inhibits the activity of the gonadotropic axis in the ovine at the level of the hypothalamus and may represent another neuromodulator of reproductive processes in animals.


Assuntos
Gonadotrofos , Hormônio Luteinizante , Feminino , Ovinos , Animais , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Hipófise/metabolismo , Gonadotrofos/metabolismo , Hormônio Foliculoestimulante , Mamíferos/metabolismo
3.
Hum Reprod ; 39(5): 1098-1104, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498835

RESUMO

STUDY QUESTION: Is there any difference in ovarian response and embryo ploidy following progesterone-primed ovarian stimulation (PPOS) using micronized progesterone or GnRH antagonist protocol? SUMMARY ANSWER: Pituitary downregulation with micronized progesterone as PPOS results in higher number of oocytes retrieved and a comparable number of euploid blastocysts to a GnRH antagonist protocol. WHAT IS KNOWN ALREADY: Although the GnRH antagonist is considered by most the gold standard protocol for controlling the LH surge during ovarian stimulation (OS) for IVF/ICSI, PPOS protocols are being increasingly used in freeze-all protocols. Still, despite the promising results of PPOS protocols, an early randomized trial reported potentially lower live births in recipients of oocytes resulting following downregulation with medroxyprogesterone acetate as compared with a GnRH antagonist protocol. The scope of the current prospective study was to investigate whether PPOS with micronized progesterone results in an equivalent yield of euploid blastocysts to a GnRH antagonist protocol. STUDY DESIGN, SIZE, DURATION: In this prospective study, performed between September 2019 to January 2022, 44 women underwent two consecutive OS protocols within a period of 6 months in a GnRH antagonist protocol or in a PPOS protocol with oral micronized progesterone. PARTICIPANTS/MATERIALS, SETTING, METHODS: Overall, 44 women underwent two OS cycles with an identical fixed dose of rFSH (225 or 300 IU) in both cycles. Downregulation in the first cycles was performed with the use of a flexible GnRH antagonist protocol (0.25 mg per day as soon as one follicle of 14 mm) and consecutively, after a washout period of 1 month, control of LH surge was performed with 200 mg of oral micronized progesterone from stimulation Day 1. After the completion of both cycles, all generated blastocysts underwent genetic analysis for aneuploidy screening (preimplantation genetic testing for aneuplody, PGT-A). MAIN RESULTS AND THE ROLE OF CHANCE: Comparisons between protocols did not reveal differences between the duration of OS. The hormonal profile on the day of trigger revealed statistically significant differences between protocols in all the tested hormones except for FSH: with significantly higher serum E2 levels, more elevated LH levels and higher progesterone levels in PPOS cycles as compared with antagonist cycles, respectively. Compared with the GnRH antagonist protocol, the PPOS protocol resulted in a significantly higher number of oocytes (12.7 ± 8.09 versus 10.3 ± 5.84; difference between means [DBM] -2.4 [95% CI -4.1 to -0.73]), metaphase II (9.1 ± 6.12 versus 7.3 ± 4.15; DBM -1.8 [95% CI -3.1 to -0.43]), and 2 pronuclei (7.1 ± 4.99 versus 5.7 ± 3.35; DBM -1.5 [95% CI -2.6.1 to -0.32]), respectively. Nevertheless, no differences were observed regarding the mean number of blastocysts between the PPOS and GnRH antagonist protocols (2.9 ± 2.11 versus 2.8 ± 2.12; DBM -0.07 [95% CI -0.67 to 0.53]) and the mean number of biopsied blastocysts (2.9 ± 2.16 versus 2.9 ± 2.15; DBM -0.07 [95% CI -0.70 to 0.56]), respectively. Concerning the euploidy rates per biopsied embryo, a 29% [95% CI 21.8-38.1%] and a 35% [95% CI 26.6-43.9%] were noticed in the PPOS and antagonist groups, respectively. Finally, no difference was observed for the primary outcome, with a mean number of euploid embryos of 0.86 ± 0.90 versus 1.00 ± 1.12 for the comparison of PPOS versus GnRh antagonist. LIMITATIONS, REASONS FOR CAUTION: The study was powered to detect differences in the mean number of euploid embryos and not in terms of pregnancy outcomes. Additionally, per protocol, there was no randomization, the first cycle was always a GnRH antagonist cycle and the second a PPOS with 1 month of washout period in between. WIDER IMPLICATIONS OF THE FINDINGS: In case of a freeze-all protocol, clinicians may safely consider oral micronized progesterone to control the LH surge and patients could benefit from the advantages of a medication of oral administration, with a potentially higher number of oocytes retrieved at a lower cost, without any compromise in embryo ploidy rates. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by an unrestricted grant from Theramex. N.P.P. has received Research grants from Merck Serono, Organon, Ferring Pharmaceutical, Roche, Theramex, IBSA, Gedeon Richter, and Besins Healthcare; honoraria for lectures from: Merck Serono, Organon, Ferring Pharmaceuticals, Besins International, Roche Diagnostics, IBSA, Theramex, and Gedeon Richter; consulting fees from Merck Serono, Organon, Besins Healthcare, and IBSA. M.d.M.V., F.M., and I.R. declared no conflicts of interest. TRIAL REGISTRATION NUMBER: The study was registered at Clinical Trials Gov. (NCT04108039).


Assuntos
Hormônio Liberador de Gonadotropina , Indução da Ovulação , Ploidias , Progesterona , Feminino , Humanos , Indução da Ovulação/métodos , Progesterona/administração & dosagem , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Adulto , Estudos Prospectivos , Gravidez , Antagonistas de Hormônios/administração & dosagem , Antagonistas de Hormônios/farmacologia , Blastocisto/efeitos dos fármacos , Taxa de Gravidez , Recuperação de Oócitos , Transferência Embrionária/métodos , Administração Oral , Injeções de Esperma Intracitoplásmicas/métodos
4.
J Biochem Mol Toxicol ; 38(4): e23699, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38532648

RESUMO

The endocrine disruptor hexavalent chromium [Cr(VI)] is a proven reproductive toxicant. We recently demonstrated that prenatal Cr(VI) exposure causes testicular resistance to gonadotropins, resulting in hypergonadotropic hypoandrogenism in F1 rats. However, the mechanism driving hypergonadotropism in F1 rats exposed to Cr(VI) prenatally remains an enigma. Therefore, we hypothesized that 'Prenatal Cr(VI) exposure may disrupt steroid hormones-mediated negative feedback regulation of the hypothalamic GnRH, and its receptor in the pituitary of F1 rats, leading to hypergonadotropism.' We administered potassium dichromate (50, 100, or 200 mg/L) to pregnant rats through drinking water between days 9 and 14, and their male F1 offspring were euthanized at 60 days of age. Prenatal Cr(VI) exposure in F1 rats resulted in the accumulation of Cr in the hypothalamus and pituitary. Western blot detected decreased hypothalamic GnRH, Kisspeptin1, and its receptor GPR54, along with diminished ERα, AR, aromatase, and 5α reductase, and GnRH regulatory transcription factors Pit-1 and GATA-4 proteins. Immunohistochemical studies revealed increased immunopositivity of GnRH receptor, AR, 5α reductase, ERα, ERß, and aromatase proteins in the pituitary, whereas decreased Kisspeptin1, GPR54, and inhibin ß. Our findings imply that Cr(VI) exposure during the prenatal period disrupts the hypothalamic Kisspeptin-GPR54-Pit-1/GATA4-GnRH network, boosting the pituitary GnRH receptor. We conclude that prenatal exposure to Cr(VI) alters GnRH expression in the hypothalamus and its receptor in the pituitary of F1 progeny through interfering with the negative feedback effect of androgens and estrogens.


Assuntos
Cromo , Efeitos Tardios da Exposição Pré-Natal , Receptores LHRH , Feminino , Gravidez , Humanos , Ratos , Masculino , Animais , Receptores LHRH/metabolismo , Receptor alfa de Estrogênio/metabolismo , Aromatase , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Hipotálamo , Hormônio Liberador de Gonadotropina/metabolismo
5.
Int J Mol Sci ; 25(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38473910

RESUMO

Caffeine is one of the most widely consumed psychoactive drugs in the world. It easily crosses the blood-brain barrier, and caffeine-interacting adenosine and ryanodine receptors are distributed in various areas of the brain, including the hypothalamus and pituitary. Caffeine intake may have an impact on reproductive and immune function. Therefore, in the present study performed on the ewe model, we decided to investigate the effect of peripheral administration of caffeine (30 mg/kg) on the secretory activity of the hypothalamic-pituitary unit which regulates the reproductive function in females during both a physiological state and an immune/inflammatory challenge induced by lipopolysaccharide (LPS; 400 ng/kg) injection. It was found that caffeine stimulated (p < 0.01) the biosynthesis of gonadotropin-releasing hormone (GnRH) in the hypothalamus of ewe under both physiological and inflammatory conditions. Caffeine also increased (p < 0.05) luteinizing hormone (LH) secretion in ewes in a physiological state; however, a single administration of caffeine failed to completely release the LH secretion from the inhibitory influence of inflammation. This could result from the decreased expression of GnRHR in the pituitary and it may also be associated with the changes in the concentration of neurotransmitters in the median eminence (ME) where GnRH neuron terminals are located. Caffeine and LPS increased (p < 0.05) dopamine in the ME which may explain the inhibition of GnRH release. Caffeine treatment also increased (p < 0.01) cortisol release, and this stimulatory effect was particularly evident in sheep under immunological stress. Our studies suggest that caffeine affects the secretory activity of the hypothalamic-pituitary unit, although its effect appears to be partially dependent on the animal's immune status.


Assuntos
Cafeína , Hormônio Liberador de Gonadotropina , Feminino , Ovinos , Animais , Hormônio Liberador de Gonadotropina/metabolismo , Cafeína/farmacologia , Hormônio Luteinizante/metabolismo , Lipopolissacarídeos/farmacologia , Hipotálamo/metabolismo
6.
Theriogenology ; 219: 157-166, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38432143

RESUMO

To understand better the role that kisspeptin plays in regulating seasonal and estrous cycle changes in the mare, this study investigated the number, location and interactions between GnRH, kisspeptin and RFRP-3 neurons in the equine hypothalamus. Hypothalami were collected from mares during the non-breeding season, vernal transition and various stages of the breeding season. Fluorescent immunohistochemistry was used to label the neuropeptides of interest. GnRH cells were observed primarily in the arcuate nucleus (ARC), while very few labeled cells were identified in the pre-optic area (POA). Kisspeptin cells were identified primarily in the ARC, with a small number of cells observed dorsal to the ARC, surrounding the third ventricle (3V). The mean number of kisspeptin cells varied between animals and typically showed no pattern associated with season or stage of estrous cycle, but a seasonal difference was identified in the ARC population. Small numbers of RFRP-3 cells were observed in the ARC, ventromedial hypothalamus (VMH) and dorsomedial hypothalamus (DMH). The mean number of RFRP-3 cells appeared higher in pre-ovulatory animals compared to all other stages. The percentage of GnRH cell bodies with kisspeptin appositions did not change with season or stage of estrous cycle. The percentage of kisspeptin cells receiving inputs from RFRP-3 fibers did not vary with season or stage of estrous cycle. These interactions suggest the possibility of the presence of an ultra-short loop feedback system between these three peptides. The changes in RFRP-3 neurons suggest the possibility of a role in the regulation of reproduction in the horse, but it is unlikely to be as a gonadotropin inhibitory factor.


Assuntos
Hormônio Liberador de Gonadotropina , Neuropeptídeos , Cavalos , Animais , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Kisspeptinas/metabolismo , Estações do Ano , Neuropeptídeos/fisiologia , Hipotálamo/metabolismo , Ciclo Estral/fisiologia , Neurônios
7.
Biol Reprod ; 110(4): 761-771, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38374691

RESUMO

Reproduction is a high energy consuming process, so long-term malnutrition can significantly inhibit gonadal development. However, little is known about the molecular mechanism by which fasting inhibits reproduction. Our present study found that fasting could dramatically induce insulin-like growth factor binding protein 1 (IGFBP1) expression in the liver, hypothalamus, pituitary and ovaries of grass carp. In addition, IGFBP1a in the hypothalamus-pituitary-gonad axis could inhibit the development of gonads. These results indicated that fasting may participate in the regulation of fish gonadal development through the mediation of IGFBP1a. Further studies found that IGFBP1a could markedly inhibit gonadotropin-releasing hormone 3 expressions in hypothalamus cells. At the pituitary level, IGFBP1a could significantly reduce the gonadotropin hormones (LH and FSH) expression by blocking the action of pituitary insulin-like growth factor 1. Interestingly, IGFBP1a could also directly inhibit the expression of lhr, fshr, and sex steroid hormone synthase genes (cyp11a, cyp17a, and cyp19a1) in the ovary. These results indicated that IGFBP1a should be a nutrient deficient response factor that could inhibit fish reproduction through the hypothalamus-pituitary-ovary axis.


Assuntos
Carpas , Ovário , Animais , Feminino , Ovário/metabolismo , Hipófise/metabolismo , Hipotálamo/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Reprodução
8.
Sci Rep ; 14(1): 3377, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336836

RESUMO

Growth hormone (GH) has a long-standing history of use as an adjunctive therapy in the treatment of poor ovarian response (POR), but the optimal dosage and timing remains unclear. The aim of this study was to evaluate and compare the efficacy of different GH supplementation protocols through a network meta-analysis (NMA) and determine the optimal treatment protocol. This study was reported based on the Preferred Reporting Items for Systematic Reviews for Network Meta-Analysis (PRISMA-NMA) statement. Databases including PubMed, Web of Science, Cochrane Library and Embase were searched until June 2023. A total of 524 records were retrieved in our search, and 23 clinical studies comprising 4889 cycles were involved. Seven different GH protocols were identified. Results showed that compared to the control group, daily administration of 4-8 IU of GH during the follicular phase of the stimulation cycle had the best comprehensive therapeutic effects on improving the number of retrieved oocytes, mature oocytes, endometrial thickness, and reducing gonadotropin requirements in POR patients undergoing assisted reproductive therapy, with a relatively brief treatment duration and a moderate total GH dose. Subgroup analysis demonstrated that this protocol could significantly improve the clinical pregnancy rate of POR patients in the randomized controlled trials (RCT) subgroup and the African subgroup. Therefore, its clinical application is suggested. Besides, the potential advantages of long-term GH supplementation protocol (using GH for at least 2 weeks before oocyte retrieval) has merit for further research. Rigorous and well-designed multi-arm RCTs are needed in the future to confirm the conclusions drawn from this study.


Assuntos
Hormônio do Crescimento , Hormônio do Crescimento Humano , Gravidez , Feminino , Humanos , Hormônio do Crescimento/uso terapêutico , Metanálise em Rede , Indução da Ovulação/métodos , Técnicas de Reprodução Assistida , Taxa de Gravidez , Hormônio do Crescimento Humano/uso terapêutico , Suplementos Nutricionais , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina , Metanálise como Assunto
9.
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
10.
Gen Comp Endocrinol ; 350: 114477, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387532

RESUMO

Gonadotropin-inhibitory hormone (GnIH) was the first reported hypothalamic neuropeptide inhibiting reproduction in vertebrates. Since its discovery in the quail brain, its orthologs have been identified in a variety of vertebrate species and even protochordates. Depending on the species, the GnIH precursor polypeptides comprise two, three or four mature peptides of the RFamide family. It has been well documented that GnIH inhibits reproduction at the brain-pituitary-gonadal levels and participates in metabolism, stress response, and social behaviors in birds and mammals. However, most studies in fish have mainly been focused on the physiological roles of GnIH in the control of reproduction and results obtained are in some cases conflicting, leaving aside its potential roles in the regulation of other functions. In this manuscript we summarize the information available in fish with respect to the structural diversity of GnIH peptides and functional roles of GnIH in reproduction and other physiological processes. We also highlight the molecular mechanisms of GnIH actions on target cells and possible interactions with other neuroendocrine factors.


Assuntos
Gonadotropinas , Hormônios Hipotalâmicos , Animais , Gonadotropinas/metabolismo , Vertebrados/metabolismo , Peptídeos/metabolismo , Hipotálamo/metabolismo , Reprodução/fisiologia , Peixes/metabolismo , Mamíferos/metabolismo , Hormônios Hipotalâmicos/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo
11.
Mol Nutr Food Res ; 68(5): e2300270, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38389198

RESUMO

SCOPE: The disturbance of the hypothalamic-pituitary-gonadal (HPG) axis, gut microbiota (GM) community, and short-chain fatty acids (SCFAs) is a triggering factor for pubertal onset. The study investigates the effects of the long-term intake of aspartame on puberty and GM in animals and humans. METHODS AND RESULTS: Aspartame-fed female offspring rats result in vaginal opening time prolongation, serum estrogen reduction, and serum luteinizing hormone elevation. , 60 mg kg-1 aspartame treatment decreases the mRNA levels of gonadotropin-releasing hormone (GnRH), Kiss1, and G protein-coupled receptor 54 (GPR54), increases the mRNA level of RFamide-related peptide-3 (RFRP-3), and decreases the expression of GnRH neurons in the hypothalamus. Significant differences in relative bacterial abundance at the genus levels and decreased fecal SCFA levels are noted by 60 mg kg-1 aspartame treatment. Among which, Escherichia-Shigella is negatively correlated with several SCFAs. In girls, high-dose aspartame consumption decreases the risk of precocious puberty. CONCLUSIONS: Aspartame reduces the chance of puberty occurring earlier than usual in female offspring and girls. Particularly, 60 mg kg-1 aspartame-fed female offspring delays pubertal onset through the dysregulation of HPG axis and GM composition by inhibiting the Kiss1/GPR54 system and inducing the RFRP-3. An acceptable dose of aspartame should be recommended during childhood.


Assuntos
Kisspeptinas , Puberdade Tardia , Humanos , Ratos , Feminino , Animais , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Aspartame/efeitos adversos , Aspartame/metabolismo , Puberdade Tardia/metabolismo , Ratos Sprague-Dawley , Maturidade Sexual/fisiologia , Hormônio Liberador de Gonadotropina/genética , Hipotálamo/metabolismo , Puberdade , RNA Mensageiro/metabolismo
12.
Poult Sci ; 103(3): 103422, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228063

RESUMO

The egg-laying interval (LI) directly reflects the laying performance of breeding pigeons, influenced by reproductive hormones. This study aimed to assess reproductive hormone levels in serum and the expression of related genes and their receptors in the hypothalamus and pituitary gland in 4 stages: first (LI1), third (LI3), fifth (LI5), and seventh (LI7) days. The results showed that serum gonadotropin-releasing hormone (GnRH) level decreased from LI1 to LI7 (P < 0.01) and peaked in LI1. The serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels stayed at high levels from LI1 to LI5. The FSH level decreased slightly from LI5 to LI7 (P > 0.05), but the LH level decreased rapidly (P < 0.01). The prolactin (PRL) levels significantly increased in LI5 (P < 0.01) compared with LI1 and then stayed at a high level. The GnRH1 expression in the hypothalamus had no significant change in LI (P > 0.05). However, the GnRHR first decreased from LI1 to LI3 (P < 0.05) and then increased. The FSH mRNA level in the pituitary gland decreased from LI1 to LI3 and slightly increased in LI5 (P > 0.05). The change pattern of FSHR was similar to that of FSH and peaked in LI5 (P < 0.05). The LH expression level was the highest in LI5 and significantly higher than that in LI3 and LI7 (P < 0.05). However, the LHR mRNA level decreased in LI (P < 0.05). The expression patterns of PRL and PRLR were similar; they were upregulated in LI and peaked in LI7 (P < 0.01). The expression pattern of GnRHR was similar to that of FSH, LH, and FSHR, suggesting the critical role of GnRHR in LI. Furthermore, the expression levels of these genes peaked in LI5, closely correlating with the maturation of the first largest follicle in pigeons. PRL-PRLR signaling inhibited GnRH activity to promote ovulation. This study provided a basis for further investigating the molecular mechanisms underlying the regulation of reproduction in pigeons.


Assuntos
Galinhas , Columbidae , Animais , Feminino , Columbidae/genética , Hipotálamo , Hipófise , Hormônio Liberador de Gonadotropina/genética , RNA Mensageiro , Hormônio Foliculoestimulante , Expressão Gênica
13.
Phytomedicine ; 124: 155280, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38183697

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common reproductive-endocrine condition in premenopausal women. Troxerutin, a common clinical anti-coagulant agent, was shown to work as a strong IL-22 boosting agent counteracting the hyperactivated gonadotrophin releasing hormone (GnRH) neurons and heightened GnRH release, the neuroendocrine origin of PCOS with unknown mechanism in rats. Exploring the off-label use of troxerutin medication for PCOS is thus sorely needed. METHODS: Serum IL-22 content and hypothalamic IL-22 protein were detected. Inflammatory factor levels in hypothalamo-pituitary were evaluated. Immunofluorescence staining was employed to determine the activation and M1/M2-prone polarization of microglia in arcuate hypothalamus and median eminence. RNA-sequencing and transcriptome analysis were applied to explore the potential driver of microglia M2-polarization in response to IL-22 bolstering effect. The function of microglial IL-22/IL-22R1/IRF3 system was further verified using in vivo knockdown of IL-22R1 and a potent IRF3 inhibitor in BV2 microglial cell lines in vitro. RESULTS: Troxerutin augmented serum IL-22 content, and its consequent spillover into the hypothalamus led to the direct activation of IL-22R1/IRF3 system on microglia, thereby promoted microglia M2 polarization in arcuate hypothalamus and median eminence, dampened hypothalamic neuroinflammation, inhibited hyperactive GnRH and rescued a breadth of PCOS-like traits in dihydrotestosterone (DHT) rats. The salutary effects of troxerutin treatment on hypothalamic neuroinflammation, microglial M1/2 polarization, GnRH secretion and numerous PCOS-like features were blocked by in vivo knockdown of IL-22R1. Moreover, evidence in vitro illustrated that IL-22 supplement to BV-2 microglia cell lines promoted M2 polarization, overproduction of anti-inflammatory marker and limitation of pro-inflammatory factors, whereas these IL-22 effects were blunted by geldanamycin, a potent IRF3 inhibitor. CONCLUSION: Here, the present study reported the potential off-label use of troxerutin medication, a common clinical anti-coagulant agent and an endogenous IL-22 enhancer, for multiple purposes in PCOS. The rational underlying the application of troxerutin as a therapeutic choice in PCOS derived from its activity as an IL-22 memetic agent targeting the neuro-endocrine origin of PCOS, and its promotive impact on microglia M2 polarization via activating microglial IL-22R1/IRF3 system in the arcuate hypothalamus and median eminence of DHT female rats.


Assuntos
Hidroxietilrutosídeo/análogos & derivados , Síndrome do Ovário Policístico , Receptores de Interleucina , Humanos , Ratos , Feminino , Animais , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/tratamento farmacológico , Di-Hidrotestosterona/efeitos adversos , Di-Hidrotestosterona/metabolismo , Microglia , Doenças Neuroinflamatórias , Interleucina 22 , Hipotálamo/metabolismo , Hormônio Liberador de Gonadotropina/efeitos adversos , Hormônio Liberador de Gonadotropina/metabolismo , Fator Regulador 3 de Interferon/metabolismo
14.
Physiol Rep ; 12(2): e15923, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38268116

RESUMO

Normal gonadal function can be disrupted by hypothyroidism. Hypothyroidism disturbs testicular function directly and centrally by affecting the hypothalamic-pituitary-testicular axis with unclear mechanism. As nesfatin-1 neurons co-localized with TRH and GnRH neurons in the hypothalamus, it could play a role in centrally hypothyroidism induced testicular dysfunction. Selenium (Se), by affecting thyroid iodide supply, could relieve these disturbances. So, we aim to identify the role of nesfatin-1 as a link between testicular dysfunction and hypothyroidism through modulating the MAPK/ERK pathway while discussing the possible role of Se in alleviating hypothyroidism and associated testicular damage. Forty male rats were divided equally into: Control: distilled water, Se: Se orally, Propylthiouracil (PTU): PTU orally, PTU + Se: Se with PTU orally. Serum thyroid function, gonadal hormones, nesfatin-1, testicular redox status, sperm analysis, brain tissue GnRH, nucleobindin 2-derived polypeptide, pMAPK/ERK gene expression, histological changes and immunohistochemical expression of testicular proliferating cell antigen (PCNA) were done. PTU induced hypothyroidism and reduction of gonadal hormones which both were correlated with reduced nesfatin-1. There was testicular stress with reduced GnRH, NUCB2, pMAPK/ERK gene expression, and PCNA immunopositive cells. These parameters were reversed by Se. Nesfatin-1 could be the central link between hypothyroidism and disturbances of the hypothalamic pituitary testicular axis.


Assuntos
Hipotireoidismo , Selênio , Masculino , Animais , Ratos , Selênio/farmacologia , Antígeno Nuclear de Célula em Proliferação , Sêmen , Hormônios Gonadais , Hormônio Liberador de Gonadotropina
15.
J Assist Reprod Genet ; 41(3): 609-612, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246921

RESUMO

Luteinizing hormone (LH) is present throughout the natural follicular phase. However, the debate is still not settled on whether LH is needed during ovarian stimulation in IVF. This commentary looks at the evolution of this debate, mentioning three elephants in the room that were ignored by the Pharma industry, professional organizations, and clinicians alike: 1. The different endocrinology between the long agonist and the antagonist protocols. 2. The fixed dose of the two most widely commercially available antagonist preparations, namely cetrorelix and ganirelix. 3. The fact that most research in this area uses population-based criteria, ignoring endocrine parameters. Individual genetics of the LH receptor gene may also serve to individualize LH needs during stimulation; however, the jury is still out regarding this approach. CONCLUSIONS: Individual endocrine and genetics parameters may shed meaningful light on the question of LH supplemental during ovarian stimulation.


Assuntos
Características Humanas , Hormônio Luteinizante , Feminino , Humanos , Estradiol , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina , Indução da Ovulação/métodos , Política , Suplementos Nutricionais , Antagonistas de Hormônios
16.
Horm Behav ; 159: 105478, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38241961

RESUMO

Early life adversity in the form of childhood maltreatment in humans or as modeled by maternal separation (MS) in rodents is often associated with an earlier emergence of puberty in females. Earlier pubertal initiation is an example of accelerated biological aging and predicts later risk for anxiety in women, especially in populations exposed to early life trauma. Here we investigated external pubertal markers as well as hypothalamic gene expression of pubertal regulators kisspeptin and gonadotropin-releasing hormone, to determine a biological substrate for MS-induced accelerated puberty. We further investigated a mechanism by which developmental stress might regulate pubertal timing. As kisspeptin and gonadotropin-releasing hormone secretion are typically inhibited by corticotropin releasing hormone at its receptor CRH-R1, we hypothesized that MS induces a downregulation of Crhr1 gene transcription in a cell-specific manner. Finally, we explored the association between pubertal timing and anxiety-like behavior in an acoustic startle paradigm, to drive future preclinical research linking accelerated puberty and anxiety. We replicated previous findings that MS leads to earlier puberty in females but not males, and found expression of kisspeptin and gonadotropin-releasing hormone mRNA to be prematurely increased in MS females. RNAscope confirmed increased expression of these genes, and further revealed that kisspeptin-expressing neurons in females were less likely to express Crhr1 after MS. Early puberty was associated with higher acoustic startle magnitude in females. Taken together, these findings indicate precocial maturation of central pubertal timing mechanisms after MS, as well as a potential role of CRH-R1 in these effects and an association with a translational measure of anxiety.


Assuntos
Experiências Adversas da Infância , Kisspeptinas , Humanos , Ratos , Feminino , Animais , Kisspeptinas/genética , Kisspeptinas/metabolismo , Privação Materna , Hipotálamo/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Maturidade Sexual/fisiologia
17.
BMJ Open ; 14(1): e078989, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216200

RESUMO

INTRODUCTION: Uterine fibroids affect 30%-77% of reproductive-age women and are a significant cause of infertility. Surgical myomectomies can restore fertility, but they often have limited and temporary benefits, with postoperative complications such as adhesions negatively impacting fertility. Existing medical therapies, such as oral contraceptives, gonadotropin hormone-releasing hormone (GnRH) analogues and GnRH antagonists, can manage fibroid symptoms but are not fertility friendly. This study addresses the pressing need for non-hormonal, non-surgical treatment options for women with fibroids desiring pregnancy. Previous preclinical and clinical studies have shown that epigallocatechin gallate (EGCG) effectively reduces uterine fibroid size. We hypothesise that EGCG from green tea extract will shrink fibroids, enhance endometrial quality and increase pregnancy likelihood. To investigate this hypothesis, we initiated a National Institute of Child Health and Human Development Confirm-funded trial to assess EGCG's efficacy in treating women with fibroids and unexplained infertility. METHODS AND ANALYSIS: This multicentre, prospective, interventional, randomised, double-blinded clinical trial aims to enrol 200 participants with fibroids and unexplained infertility undergoing intrauterine insemination (IUI). Participants will be randomly assigned in a 3:1 ratio to two groups: green tea extract (1650 mg daily) or a matched placebo, combined with clomiphene citrate-induced ovarian stimulation and timed IUI for up to four cycles. EGCG constitutes approximately 45% of the green tea extract. The primary outcome is the cumulative live birth rate, with secondary outcomes including conception rate, time to conception, miscarriage rate, change in fibroid volume and symptom severity scores and health-related quality of life questionnaire scores. ETHICS AND DISSEMINATION: The FRIEND trial received approval from the Food and Drug adminstration (FDA) (investigational new drug number 150951), the central Institutional Review Board (IRB) at Johns Hopkins University and FRIEND-collaborative site local IRBs. The data will be disseminated at major conferences, published in peer-reviewed journals and support a large-scale clinical trial. TRIAL REGISTRATION NUMBER: NCT05364008.


Assuntos
Catequina/análogos & derivados , Infertilidade , Leiomioma , Gravidez , Criança , Feminino , Humanos , Chá , Qualidade de Vida , Estudos Prospectivos , Leiomioma/complicações , Leiomioma/tratamento farmacológico , Leiomioma/cirurgia , Infertilidade/terapia , Fertilidade , Indução da Ovulação/métodos , Hormônio Liberador de Gonadotropina/uso terapêutico , Taxa de Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
18.
J Mol Endocrinol ; 72(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085702

RESUMO

The exact neural construct underlying the dynamic secretion of gonadotrophin-releasing hormone (GnRH) has only recently been identified despite the detection of multiunit electrical activity volleys associated with pulsatile luteinising hormone (LH) secretion four decades ago. Since the discovery of kisspeptin/neurokinin B/dynorphin neurons in the mammalian hypothalamus, there has been much research into the role of this neuronal network in controlling the oscillatory secretion of gonadotrophin hormones. In this review, we provide an update of the progressive application of cutting-edge techniques combined with mathematical modelling by the neuroendocrine community, which are transforming the functional investigation of the GnRH pulse generator. Understanding the nature and function of the GnRH pulse generator can greatly inform a wide range of clinical studies investigating infertility treatments.


Assuntos
Hormônio Liberador de Gonadotropina , Hormônio Luteinizante , Animais , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Neurocinina B/metabolismo , Dinorfinas/metabolismo , Kisspeptinas/metabolismo , Núcleo Arqueado do Hipotálamo/metabolismo , Mamíferos/metabolismo
19.
Endocrine ; 83(3): 733-746, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37966704

RESUMO

OBJECTIVE: We examined how the sex steroids influence the synthesis of gonadotropins. MATERIALS AND METHODS: The effects of sex steroids estradiol (E2), progesterone (P4), and dihydrotestosterone (DHT) in pituitary gonadotroph cell model (LßT2 cells) in vitro and ovary-intact rats in vivo were examined. The effects of sex steroids on Kiss1 gene expression in the hypothalamus were also examined in ovary-intact rats. RESULTS: In LßT2 cells, E2 increased common glycoprotein alpha (Cga) and luteinizing hormone beta (Lhb) subunit promoter activity as well as their mRNA expression. Although gonadotropin subunit promoter activity was not modulated by P4, Cga and Lhb mRNA expression was increased by P4. DHT inhibited Cga and Lhb mRNA expression with a concomitant decrease in their promoter activity. During the 2-week administration of exogenous E2 to ovary-intact rats, the estrous cycle determined by vaginal smears was disrupted. P4 or DHT administration completely eliminated the estrous cycle. Protein expression of all three gonadotropin subunits within the pituitary gland was inhibited by E2 or P4 treatment in vivo; however, DHT reduced Cga expression but did not modulate Lhb or follicle-stimulating hormone beta subunit expression. E2 administration significantly repressed Kiss1 mRNA expression in a posterior hypothalamic region that included the arcuate nucleus. P4 and DHT did not modulate Kiss1 mRNA expression in this region. In contrast, P4 administration significantly inhibited Kiss1 mRNA expression in the anterior region of the hypothalamus that included the anteroventral periventricular nucleus. The expression of gonadotropin-releasing hormone (Gnrh) mRNA in the anterior hypothalamic region, where the preoptic area is located, appeared to be decreased by treatment with E2 and P4. CONCLUSION: Our findings suggest that sex steroids have different effects in the hypothalamus and pituitary gland.


Assuntos
Kisspeptinas , Ovário , Ratos , Feminino , Animais , Kisspeptinas/genética , Kisspeptinas/metabolismo , Hipotálamo/metabolismo , Gonadotropinas Hipofisárias/genética , Gonadotropinas Hipofisárias/metabolismo , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Estradiol/farmacologia , RNA Mensageiro/metabolismo , Di-Hidrotestosterona/farmacologia , Expressão Gênica
20.
Endocr Rev ; 45(1): 30-68, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-37467734

RESUMO

Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and pulsatile GnRH secretion. Their critical role in reproductive health was first identified after inactivating variants in genes encoding for KP or NKB signaling were shown to result in congenital hypogonadotropic hypogonadism and a failure of pubertal development. Over the past 2 decades since their discovery, a wealth of evidence from both basic and translational research has laid the foundation for potential therapeutic applications. Beyond KP's function in the hypothalamus, it is also expressed in the placenta, liver, pancreas, adipose tissue, bone, and limbic regions, giving rise to several avenues of research for use in the diagnosis and treatment of pregnancy, metabolic, liver, bone, and behavioral disorders. The role played by NKB in stimulating the hypothalamic thermoregulatory center to mediate menopausal hot flashes has led to the development of medications that antagonize its action as a novel nonsteroidal therapeutic agent for this indication. Furthermore, the ability of NKB antagonism to partially suppress (but not abolish) the reproductive endocrine axis has supported its potential use for the treatment of various reproductive disorders including polycystic ovary syndrome, uterine fibroids, and endometriosis. This review will provide a comprehensive up-to-date overview of the preclinical and clinical data that have paved the way for the development of diagnostic and therapeutic applications of KP and NKB.


Assuntos
Kisspeptinas , Neurocinina B , Gravidez , Feminino , Humanos , Neurocinina B/genética , Neurocinina B/metabolismo , Kisspeptinas/uso terapêutico , Hormônio Liberador de Gonadotropina/metabolismo , Reprodução/fisiologia , Hipotálamo
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