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Background/Objective: Autoimmune thyroid diseases (AITD) affect 2 to 5% of the general population. This study aimed to determine changes in activity of A-Tg and A-TPO antibodies before, during, and after pregnancy in women with previous AITD. Methods: This was a single-center study with a retrospective review of the medical records of 30 female patients aged 25-41 years who came to our endocrinology service in the city of Santo André, state of São Paulo, Brazil, to investigate thyroid diseases. The following data were reviewed: total triiodothyronine (totalT3), total thyroxine (totalT4), free thyroxine (FT4), thyroid-stimulating hormone (TSH), and anti-TSH receptor antibodies (anti-TSH receptor or anti-thyrotropin receptor antibodies (TRAb), anti-thyroid peroxidase (A-TPO), and anti-thyroglobulin (A-Tg)). These data were reviewed for 30 patients before and during the three trimesters of pregnancy and during the three months after pregnancy. Results: During gestation, we observed a progressive decrease in the blood values of A-TPO and A-Tg, which reached their lowest values in the third trimester of pregnancy, but after birth, they returned to values statistically equivalent to those before pregnancy. Analyzing the three trimesters and the post-pregnancy period, A-TPO increased 192% between the first trimester and postpartum (p = 0.009); it increased 627% between the second trimester and postpartum (p < 0.001); and it increased >1000% between the third trimester and postpartum (p < 0.001). There was no significant difference in the A-TPO values between the pre- and post-gestational periods (p = 1.00), between the first and second trimesters (p = 0.080), or between the second and third trimesters (p = 0.247). Conclusions: According to the results presented here, we observed changes in the activities of A-Tg and A-TPO antibodies during and after pregnancy in women with previous AITD. In women who intend to become pregnant, are pregnant, or have given birth within three months, it is essential to monitor A-TPO, A-Tg, and thyroid function as well as serum thyroid hormones and TSH to identify thyroid dysfunction in a timely manner and adjust the treatment strategy to avoid the deleterious effects of hypothyroidism on both mother and baby during and after pregnancy.
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This narrative review delves into the evolving landscape of fertility preservation techniques, with a particular focus on their use in patients undergoing oncology treatment that carries a risk of ovarian insufficiency. Advances in established methods such as cryopreservation of oocytes and embryos are highlighted, and the increasing use of gonadotropin-releasing hormone (GnRH) agonists is discussed. The review also addresses the complexities and controversies associated with these approaches, such as the 'flare-up' effect associated with GnRH agonists and the potential of GnRH antagonists to reduce the risk of ovarian hyperstimulation syndrome. Despite advances in fertility preservation, the report highlights the challenges we face, including the need for personalized treatment protocols and the management of associated risks. It calls for continued research and collaboration between healthcare professionals to refine these techniques and ultimately improve reproductive outcomes for patients facing the prospect of fertility-impairing treatment.
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This study aimed to evaluate the effects of different doses of equine chorionic gonadotropin (eCG; 200 and 300 IU) administered at the end of a fixed-time artificial insemination (FTAI) treatment protocol on ovulation, pregnancy, and twin rates in Bos taurus beef heifers. In addition, pregnancy losses in heifers with singleton and twin pregnancies were determined. A total of 2382 Angus heifers treated with a 6-day estradiol/progesterone-based protocol for FTAI (J-Synch protocol) were randomly allocated to two experimental groups to receive 200 or 300 IU of eCG administered intramuscularly at the time of intravaginal progesterone device removal; FTAI was performed from 60 to 72 h after device removal. The pregnancy rate did not differ (P = 0.89) between the 200 and 300 IU eCG groups. The number of corpus luteum induced by both eCG doses was determined by ultrasonographic examination 14 days after insemination and those treated with 300 IU of eCG had a greater double ovulation rate (P < 0.05). In addition, 300 IU eCG treated heifers had a higher twinning rate on day 30 of gestation (P < 0.05) and parturition (P < 0.05). Pregnancy losses from 30 days of gestation to calving did not differ between heifers treated with 200 and 300 IU of eCG (P = 0.70). However, regardless of the experimental group, heifers bearing twins had greater pregnancy losses than heifers with singletons (P < 0.05). In conclusion, reducing the dose of eCG from 300 to 200 IU under FTAI treatment protocol decreases double ovulation and twinning rates, maintaining a similar pregnancy rate in heifers. Nulliparous cows carrying two fetuses suffer greater pregnancy losses than cows with singletons.
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Gonadotropinas Equinas , Inseminação Artificial , Ovulação , Animais , Feminino , Gravidez , Bovinos/fisiologia , Inseminação Artificial/veterinária , Ovulação/efeitos dos fármacos , Gonadotropinas Equinas/farmacologia , Gonadotropinas Equinas/administração & dosagem , Gonadotropina Coriônica/farmacologia , Gonadotropina Coriônica/administração & dosagem , Aborto Animal , Gravidez de Gêmeos , Progesterona/administração & dosagem , Progesterona/farmacologia , Taxa de GravidezRESUMO
Objective: Both pulsatile gonadotropin-releasing hormone (GnRH) and combined gonadotropin therapy are effective to induce spermatogenesis in men with congenital hypogonadotropic hypogonadism (CHH). This study aimed to evaluate the effect of pulsatile GnRH therapy on spermatogenesis in male patients with CHH who had poor response to combined gonadotropin therapy. Materials and methods: Patients who had poor response to combined gonadotropin therapy ≥ 6 months were recruited and shifted to pulsatile GnRH therapy. The rate of successful spermatogenesis, the median time to achieve spermatogenesis, serum gonadotropins, testosterone, and testicular volume were used for data analysis. Results: A total of 28 CHH patients who had poor response to combined gonadotropin (HCG/HMG) therapy for 12.5 (6.0, 17.75) months were recruited and switched to pulsatile GnRH therapy for 10.0 (7.25, 16.0) months. Sperm was detected in 17/28 patients (60.7%). The mean time for the appearance of sperm in semen was 12.0 (7.5, 17.5) months. Compared to those who could not achieve spermatogenesis during pulsatile GnRH therapy, the successful group had a higher level of LH60min (4.32 vs. 1.10 IU/L, P = 0.043) and FSH60min (4.28 vs. 1.90 IU/L, P = 0.021). Testicular size increased during pulsatile GnRH therapy, compared to previous HCG/ HMG therapy (P < 0.05). Conclusion: For CHH patients with prior poor response to one year of HCG/ HMG therapy, switching to pulsatile GnRH therapy may induce spermatogenesis.
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Hormônio Liberador de Gonadotropina , Hipogonadismo , Espermatogênese , Testosterona , Humanos , Masculino , Espermatogênese/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/administração & dosagem , Hipogonadismo/tratamento farmacológico , Adulto , Testosterona/administração & dosagem , Testosterona/sangue , Testosterona/uso terapêutico , Adulto Jovem , Resultado do Tratamento , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/uso terapêutico , Menotropinas/administração & dosagem , Menotropinas/uso terapêutico , Testículo/efeitos dos fármacos , Quimioterapia Combinada , Pulsoterapia , AdolescenteRESUMO
This study evaluated the efficacy of the administration of different doses of equine chorionic gonadotropin (eCG; 0 IU, 200 IU, or 300 IU) at the time of the progesterone device removal in 2-year-old Nelore (Bos indicus) heifers synchronized for fixed-timed artificial insemination (FTAI). On day 0 (D0), a total of 398 heifers received 2 mg of oestradiol benzoate i.m., 0.53 mg of cloprostenol i.m., and an eight-day previously used (second use) intravaginal device containing 1 g of progesterone (P4). Eight days later (D8), simultaneous with the P4 device removal, 0.5 mg of oestradiol cypionate i.m. and 0.53 mg of cloprostenol i.m. were administered. At the same time, heifers were randomly assigned to receive one of the following treatments: G-0 IU (n = 141; no eCG treatment), G-200 IU (n = 132; treated with 200 IU of eCG), and G-300 IU (n = 125; treated with 300 IU of eCG). FTAI was performed 48 h after the P4 device removal (D10). Ultrasonographic evaluations were performed at D0, D10, and D17. Heifers were scanned to measure the size of the largest follicle (LF), the presence, number, and size of the corpus luteum (CL), and the ovulation rate. Subsequently, at D40, the heifers underwent scanning to determine the pregnancy rate and identify any twin pregnancies. Additionally, at D70, scans were performed to assess pregnancy loss (PG). Data were analysed by orthogonal contrasts [C1 (eCG effect): control x (200 IU + 300 IU) and C2 (eCG dose effect): 200 IU × 300 IU]. On D0, CL presence was similar between the groups [G-0 IU = 65.2% (92/141), G-200 IU = 55.3% (73/132), and G-300 IU = 63.2% (79/125); p = .16]. No interactions between the presence of CL on D0 and eCG treatment were found for any of the variables (p > .05). The diameter of the LF at FTAI (D10) was not influenced by eCG treatment (p = .22) or eCG dose (p = .18). However, treatment with eCG increased the diameter of the CL at D17 (G-0 IU = 15.7 ± 0.3 mmb , G-200 IU = 16.6 ± 0.2 mma , and G-300 IU = 16.6 ± 0.3 mma ; p = .001), regardless of the dose used (p = .94). The ovulation rate was higher in heifers treated with eCG [G-0 IU = 79.4%b (112/141), G-200 IU = 90.2%a (119/132), and G-300 IU = 93.6%a (117/125); p = .002], but there was no effect of eCG dose (p = .36). Pregnancy per AI (P/AI) on D40 [G-0 IU = 32.6%b (46/141), G-200 IU = 42.4%a (56/132), and G-300 IU = 42.4%a (53/125); P = 0.05] and D70 [G-0 IU = 29.1%b (41/141), G-200 IU = 40.9%a (54/132), and G-300 IU = 40.8%a (51/125); p = .02] were higher on heifers that received eCG; however, no dose effect was observed for P/AI on D40 (p = .89) nor D70 (p = .98). Pregnancy loss between D40 and D70 tended to reduce (p = .07) in eCG-treated heifers without dose effect (p = .91). Heifers with CL at D0 presented a greater follicle diameter (LF) on D10 (With CL = 11.2 ± 0.2 mm and Without CL = 10.2 ± 0.2 mm; p = .05), CL diameter on D17 (With CL = 15.8 ± 0.03 mm and Without CL = 11.8 ± 0.6 mm; p = .01), and ovulation rate [With CL = 95.5% (233/244) and Without CL = 74.7% (115/154); p = .01]. However, no difference in pregnancy rate at D40 (p = .52) and D70 (p = .84) was found. In conclusion, eCG treatment increases ovulation and pregnancy rates of heifers submitted to a FTAI protocol. Furthermore, eCG treatment increases the diameter of the CL after FTAI and reduces pregnancy losses. No dose effect was observed, suggesting Nelore (Bos indicus) heifers respond to 200 IU of eCG treatment for FTAI.
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Doenças dos Bovinos , Doenças dos Cavalos , Gravidez , Bovinos , Animais , Feminino , Cavalos , Progesterona/farmacologia , Aborto Animal , Ovulação , Estradiol/farmacologia , Cloprostenol/farmacologia , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Sincronização do Estro/métodosRESUMO
OBJECTIVE: To evaluate the efficacy of sublingually administered human chorionic gonadotropin (HCG) in combination with clomiphene citrate (CC) or letrozole (LTZ) for ovulation induction. METHODS: In this prospective, double-blind, randomized study, the patients were divided into two placebo groups and two intervention groups using CC, LTZ, and HCG. RESULTS: There were no statistically significant differences in ovulation induction between the groups. We compared endometrial thickness at the beginning of the cycle and during the pre-ovulatory period, and detected a moderately positive correlation when CC was administered with HCG. CONCLUSIONS: Sublingual HCG with CC caused a moderately positive correlation with endometrial thickening when compared with that at the beginning of the cycle and during the pre-ovulatory period. There was no significant change in the number of pre-ovulatory follicles.
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Infertilidade Feminina , Feminino , Humanos , Gonadotropina Coriônica/uso terapêutico , Clomifeno/uso terapêutico , Clomifeno/farmacologia , Fármacos para a Fertilidade Feminina/uso terapêutico , Infertilidade Feminina/etiologia , Letrozol , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Indução da Ovulação/efeitos adversos , Estudos Prospectivos , Triazóis/farmacologia , Triazóis/uso terapêutico , Método Duplo-CegoRESUMO
INTRODUCTION: The prevalence of polycystic ovarian syndrome (PCOS) in adolescent girls is between 1 and 4.3%. It remains controversial whether women with a history of idiopathic central precocious puberty (ICPP) are at increased risk for PCOS. Our objective was to assess the prevalence of PCOS in adolescents with a history of ICPP compared with healthy adolescents and the prevalence of PCOS among ICPP girls who have received or not gonadotropin-releasing hormone analogue (GnRHa) treatment. METHODS: We assessed post-menarcheal girls with a history of ICPP. Girls were evaluated at gynecological age ≥2.5 years. Data collected were age at menarche, menstrual cycle characteristics, BMI, clinical hyperandrogenism (HA), total and free testosterone levels. PCOS diagnosis was defined by criteria for adolescents. Subjects were also analyzed regarding whether or not they had received GnRHa treatment. RESULTS: Ninety-four subjects were assessed, and 63 had been treated with GnRHa. Menstrual disorders were found in 29%, clinical HA in 36%, and biochemical HA in 23%. Twelve percent met the diagnostic criteria for PCOS. There was no difference in BMI or in the incidence of menstrual dysfunction or hyperandrogenemia between treated and untreated patients. A higher proportion of clinical HA was found in untreated patients when compared to treated girls. The relative risk (RR) of developing PCOS in ICPP girls was 2.5 compared to a population of healthy adolescents. This RR was not higher in patients who received treatment with GnRHa than in those who did not. CONCLUSION: Adolescent girls with a history of ICPP have an increased risk of PCOS. This risk seems not to be related to GnRHa treatment.
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Hiperandrogenismo , Síndrome do Ovário Policístico , Puberdade Precoce , Adolescente , Feminino , Humanos , Pré-Escolar , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/epidemiologia , Puberdade Precoce/tratamento farmacológico , Prevalência , Hiperandrogenismo/complicações , Hiperandrogenismo/epidemiologia , MenarcaRESUMO
ABSTRACT Objective: Both pulsatile gonadotropin-releasing hormone (GnRH) and combined gonadotropin therapy are effective to induce spermatogenesis in men with congenital hypogonadotropic hypogonadism (CHH). This study aimed to evaluate the effect of pulsatile GnRH therapy on spermatogenesis in male patients with CHH who had poor response to combined gonadotropin therapy. Materials and methods: Patients who had poor response to combined gonadotropin therapy ≥ 6 months were recruited and shifted to pulsatile GnRH therapy. The rate of successful spermatogenesis, the median time to achieve spermatogenesis, serum gonadotropins, testosterone, and testicular volume were used for data analysis. Results: A total of 28 CHH patients who had poor response to combined gonadotropin (HCG/HMG) therapy for 12.5 (6.0, 17.75) months were recruited and switched to pulsatile GnRH therapy for 10.0 (7.25, 16.0) months. Sperm was detected in 17/28 patients (60.7%). The mean time for the appearance of sperm in semen was 12.0 (7.5, 17.5) months. Compared to those who could not achieve spermatogenesis during pulsatile GnRH therapy, the successful group had a higher level of LH60min (4.32 vs. 1.10 IU/L, P = 0.043) and FSH60min (4.28 vs. 1.90 IU/L, P = 0.021). Testicular size increased during pulsatile GnRH therapy, compared to previous HCG/HMG therapy (P < 0.05). Conclusion: For CHH patients with prior poor response to one year of HCG/HMG therapy, switching to pulsatile GnRH therapy may induce spermatogenesis.
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Abstract Objective This study aimed to investigate the effects of the presence of subchorionic hematoma (SH) in early pregnancies with threatened miscarriage (TM) on levels of first-trimester maternal serum markers, pregnancy-associated plasma protein-A (PAPP-A), and free β-human chorionic gonadotropin (β-hCG) levels. Methods The data of TM cases with SH in the first trimester between 2015 and 2021 were evaluated retrospectively. The data of age and gestational age-matched TM cases without SH were also assessed to constitute a control group. Demographic characteristics, obstetric histories, ultrasonographic findings, and free β-hCG and PAPP-A levels of the groups were compared. Results There were 119 cases in the study group and 153 cases in the control group. The median vertical and longitudinal lengths of the SH were 31 mm and 16 mm. The median age of both groups was similar (p=0.422). The MoM value of PAPP-A was 0.088 (.93) in the study group and 0.9 (0.63) in the control group (p=0.519). Similarly, the MoM value of free β-hCG was 1.04 (0.78) in the study group and 0.99 (0.86) in the control group (p=0.66). No significant relationship was found in the multivariate analysis between free β-hCG MoM, PAPP-A MoM, age, gravida, and vertical and longitudinal lengths of the hematoma (p>0.05). Conclusion The level of PAPP-A and free β-hCG were not affected by the SH. Therefore, these markers can be used reliably in TM cases with SH for the first-trimester fetal aneuploidy screening test.
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La enfermedad trofoblástica gestacional es definida como un grupo heterogéneo de lesiones, las cuales surgen a partir del epitelio trofoblástico de la placenta luego de una fertilización anormal. Se presenta el caso de una paciente de 35 años de edad, con diagnóstico de neoplasia trofoblástica gestacional posmolar en etapa I, que se detectó tras estudios imagenológicos de seguimiento y determinación de la hormona gonadotropina coriónica humana, para lo cual llevó tratamiento con quimioterapia y terapéutica de mantenimiento con metotrexato por 5 días o metotrexato/ácido folínico por 8 días, hasta la normalización de la gonadotropina coriónica humana. Lo más relevante es que, aunque estos tumores abarcan menos del 1 % de los tumores ginecológicos, representan una amenaza para la vida de las mujeres en edad reproductiva.
Gestational trophoblastic disease is defined as a heterogeneous group of lesions, which arise from the trophoblastic epithelium of the placenta after abnormal fertilization. The case of a 35-year-old female patient is presented with a diagnosis of posmolar gestational trophoblastic neoplasia in stage I, which was detected after follow-up imaging studies and determination of human chorionic gonadotropin, for which she underwent chemotherapy treatment and maintenance therapy with methotrexate for 5 days or methotrexate/folinic acid for 8 days, until normalization of human chorionic gonadotropin The most relevant thing is that, although these tumors comprise less than 1% of gynecological tumors, they represent a threat to the life of women of reproductive age.
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In the year 2002, DNA loss model (DNA-LM) postulated that neuropeptide genes to emerged through codons loss via the repair of damaged DNA from ancestral gene namely Neuropeptide Precursor Predictive (NPP), which organization correspond two or more neuropeptides precursors evolutive related. The DNA-LM was elaborated according to amino acids homology among LWamide, APGWamide, red pigment-concentrating hormone (RPCH), adipokinetic hormones (AKHs) and in silico APGW/RPCH NPPAPGW/AKH NPP were proposed. With the above principle, it was proposed the evolution of corazonin (CRZ), gonadotropin-releasing hormone (GnRH), AKH, and AKH/CRZ (ACP), but any NPP never was considered. However, the evolutive relation via DNA-LM among these neuropeptides precursors not has been established yet. Therefore, the transcriptomes from crabs Callinectes toxotes and Callinectes arcuatus were used to characterized ACP and partial CRZ precursors, respectively. BLAST alignment with APGW/RPCH NPP and APGW/AKH NPP allow identified similar NPP in the rotifer Brachionus plicatilis and other invertebrates. Moreover, three bioinformatics algorithms and manual verification were used to purify 13,778 sequences, generating a database with 719 neuropeptide precursors. Phylogenetic trees with the DNA-LM parameters showed that some ACP, CRZ, AKH2 and two NPP share nodes with GnRH from vertebrates and some of this neuropeptide had nodes in invertebrates. Whereas the phylogenetic tree with standard parameters do not showed previous node pattern. Robinson-Foulds metric corroborates the differences among phylogenetic trees. Homology relationship showed four putative orthogroups; AKH4, CRZ, and protostomes GnRH had individual group. This is the first demonstration of NPP in species and would explain the evolution neuropeptide families by the DNA-LM.
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Hormônio Liberador de Gonadotropina , Neuropeptídeos , Humanos , Animais , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Filogenia , Evolução Molecular , Neuropeptídeos/genética , Neuropeptídeos/química , Neuropeptídeos/metabolismo , Invertebrados/genética , DNA/metabolismoRESUMO
Background: Fertility preservation is an important quality of life issue for women of reproductive age undergoing gonadotoxic treatment. The possibility of administering an adjuvant long-acting gonadotropin-releasing hormone agonist (GnRHa) with the aim of reducing the number of follicles susceptible to the effects of chemotherapy and thus reducing the risk of ovarian damage is considered in some international society guidelines, particularly in certain cancers such as breast cancer. Nowadays, the administration of long-acting GnRHa after controlled ovarian hyperstimulation (COH) for fertility preservation by cryopreservation of oocytes or embryos is increasingly used. However, cases of ovarian hyperstimulation syndrome (OHSS) have been reported following the use of long-acting GnRHa after COH for fertility preservation, indicating that the potential adverse effects of this treatment need to be further investigated. Objectives: The aim of this systematic review was to comprehensively characterize patients who developed OHSS after treatment with long-acting GnRHa following COH for fertility preservation. Methods: A comprehensive search of major electronic databases through January 2023 was performed. Studies reporting the use of long-acting GnRHa after COH for fertility preservation and the development of OHSS were included. Risk of bias was assessed using a modified version of the Newcastle-Ottawa scale. Results were synthesized qualitatively. Results: Three studies with five patients met the eligibility criteria. The majority of patients were diagnosed with breast cancer and all patients underwent COH for oocyte cryopreservation. OHSS occurred in all patients after administration of long-acting GnRHa. The interval between ovulation induction and administration of long-acting GnRHa thereafter ranged from 3 to 5 days. All patients were treated conservatively and recovered without complications. Conclusion: Current evidence suggests that the use of long-acting GnRHa after COH for fertility preservation may be associated with OHSS. Healthcare providers should thoroughly discuss the benefits and risks of this intervention with their patients before making a decision. Further studies are needed to fully elucidate the causal relationship between long-acting GnRHa and OHSS in this population.
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The actions of the beta-nerve growth factor (ß-NGF) on the neuroendocrine and reproductive system have challenged classical views on the control of reproductive function. After endometrial absorption, ß-NGF triggers ovulation and promotes the development of functional corpora lutea in camelids. In this article, we review evidence showing that, in camelids, ß-NGF exerts its actions by acting in both the hypothalamus and the ovary. In the hypothalamus, ß-NGF may induce gonadotropin-releasing hormone (GnRH) release by interacting with neurons or glial cells expressing receptors for ß-NGF. The LH surge occurs under the influence of ovarian estradiol and requires the release of GnRH into the portal vessels to reach the pituitary gland. In the ovary, ß-NGF may be promoting the differentiation of follicular to luteal cells by modifying the steroidogenic profile of ovarian follicular cells in both camelids and ruminants. Although the mechanisms for these actions are largely undetermined, we aim to offer an update on the current understanding of the effects of ß-NGF controlling reproductive function in camelids and ruminants.
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Assisted Reproductive technology encompasses all techniques involving ovarian stimulation to produce high-quality oocytes and manipulation of both oocytes and sperm in vitro to produce embryos for the purpose of reproduction. The final maturation of oocytes induced by a "trigger" is a crucial step with the potential to affect in vitro fertilization outcomes. Human chorionic gonadotropin has traditionally been used as a substitute for luteinizing hormone to induce final oocyte maturation and meiosis. However, this practice may cause a potentially fatal iatrogenic complication known as ovarian hyperstimulation syndrome, which can cause significant morbidity and, in rare cases, death in otherwise healthy women. Thus, gonadotropin releasing hormone agonists have been promoted as a safer alternative for inducing oocyte maturation, albeit at the expense of luteal phase defect. Since then, various combinations of gonadotropin releasing hormone agonists and human chorionic gonadotropin have been tried. This scoping review evaluates these trigger combinations in various types of responders.
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[This corrects the article DOI: 10.3389/fnana.2022.831602.].
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The hypothalamic-pituitary-gonadal axis plays a fundamental role in the endocrine regulation of the reproductive function in mammals. Any change in the function of the participating hormones or their receptors can lead to alterations in sexual differentiation, the onset of puberty, infertility, cancer development, and other dysfunctions. In this study, we analyzed the influence of persistently elevated levels of the human chorionic gonadotropin hormone (hCG), a powerful agonist of pituitary luteinizing hormone (LH), on the reproductive axis of female mice. As a consequence of chronic hCG hypersecretion through a global expression of the hCGbeta-subunit in transgenic (TG) female mice, a series of events perturbed the prepubertal to juvenile transition. The imbalance in gonadotropin action was first manifested by precocious puberty and alterations in gonadal hormone production, with the consequent ovarian function disruption and infertility in adulthood. The expansion of cumulus cells in vivo and in vitro, ovulatory capacity, and gene expression of ovulation-related marker genes after hormone stimulation were normal in 3-week-old TG females. However, the expression of genes related to steroidogenesis and luteinization such as Lhcgr, Prlr, and the steroidogenic enzymes Cyp11a1, Cyp17a1, and Cyp19a1 were significantly elevated in the TG females. This study demonstrates that the excessive secretion of hCG in concert with high prolactin, induced premature luteinization, and enhanced ovarian steroidogenesis, as was shown by the up-regulation of luteal cell markers and progesterone synthesis in the TG mice. Furthermore, progressively impaired reproductive function of the TG females occurred from the peripubertal stage to adulthood, thus culminating in infertility.
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Gonadotropina Coriônica , Infertilidade , Humanos , Camundongos , Feminino , Animais , Gonadotropina Coriônica/farmacologia , Gonadotropina Coriônica Humana Subunidade beta/genética , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Camundongos Transgênicos , Luteinização , Mamíferos/metabolismoRESUMO
This study investigated the seasonal variations in mRNA expression of FSH (Fshr), LH (Lhr) receptors, melatonin (Mt1 and Mt2) receptors, melatonin-synthetizing enzymes (Asmt and Aanat) and melatonin concentration in developing follicles from mares raised in natural photoperiods. For one year, ultrasonographic follicular aspiration procedures were performed monthly, and small (<20 mm), medium (20 to 35 mm) and large (>35 mm) follicles were recovered from five mares. One day before monthly sample collections, an exploratory ultrasonography conducted to record the number and the size of all follicles larger than 15 mm. The total number of large follicles were higher during the spring/summer (8.2 ± 1.9) than during autumn/winter (3.0 ± 0.5). Compared to autumn/winter seasons, there was an increase of Fshr and Aanat mRNA expressions in small, medium and large follicles, an increase of Lhr and Asmt mRNA expressions in medium and large follicles and an increase of Mt1 and Mt2 mRNA expressions in small and large follicles during spring/summer. The melatonin levels in follicular fluid were also higher during the spring/summer seasons. The present data show that melatonin locally upregulates the mRNA expression of Mt1 and Mt2 receptors and melatonin-forming enzymes in mare developing follicles during reproductive seasons.
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There is evidence of the existence of an intraovarian gonadotropin-releasing hormone (GnRH) system. There are also reports about the influence of extrinsic ovarian innervation in gonadal function. Therefore, it is interesting to study the relationship between ovarian sympathetic innervation and GnRH to shed light on possible physiological and pathophysiological implications. This work aimed to investigate whether noradrenergic stimulation of the superior mesenteric ganglion (SMG) can modify the levels of ovarian GnRH and cause functional and morphological changes in the gonad through the ovarian plexus nerve (OPN), during estrus and diestrus II in rats. The SMG-OPN-Ovary system and an ovary without extrinsic innervation were removed from Holtzman rats in estrus and diestrus II stages and placed in specially designed cuvettes containing Krebs-Ringer buffer. In the experimental groups, SMGs and denervated ovaries were stimulated with 10-6 M noradrenaline (NA). GnRH and progesterone levels (in the ovarian incubation medium) and the mRNA expression of 3beta-hydroxysteroid dehydrogenase (Hsd3b3), 20alpha-hydroxysteroid dehydrogenase (Akr1c18), Bax, and Bcl2 were analyzed. Histological studies of the ovaries were performed. In estrus, NA decreased GnRH levels in both experimental schemes. Furthermore, progesterone levels increased while the Akr1c18 expression and Bax/Bcl2 ratio decreased, without causing changes in ovarian morphology. In diestrus, the noradrenergic stimulation of the ganglion increased GnRH levels, decreased progesterone levels, and increased Akr1c18 expression and Bax/Bcl2 ratio. Follicles with histoarchitecture alterations and corpus luteum with signs of cell death were observed. In denervated ovaries, NA increased the levels of GnRH and progesterone. Furthermore, NA decreased the Bax/Bcl2 ratio and histological studies revealed signs compatible with a possible atretogenic effect. In conclusion, noradrenergic stimulation of the SMG-OPN pathway regulates ovarian cyclicity. The SMG modulates the cross-talk between NA and ovarian GnRH, protecting the ovary from atretogenic effects and luteal apoptosis during estrus while inducing luteal regression in the diestrus II.
Assuntos
Ovário , Progesterona , Feminino , Ratos , Animais , Ovário/metabolismo , Progesterona/metabolismo , Norepinefrina/metabolismo , Norepinefrina/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/farmacologia , Ratos Sprague-Dawley , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Hidroxiesteroide Desidrogenases/metabolismoRESUMO
Equine chorionic gonadotropin (eCG) is a glycoprotein hormone widely used in timed artificial ovulation (TAI) and superovulation protocols to improve the reproductive performance in livestock. Until recently, the only eCG products available in the market for veterinary use consisted in partially purified preparations of pregnant mare serum gonadotropin (PMSG). Here, a bioactive recombinant eCG (reCG) produced in suspension CHO-K1 cells was purified employing different chromatographic methods (hydrophobic interaction chromatography and reverse-phase (RP)-HPLC) and compared with a RP-HPLC-purified PMSG. To gain insight into the structural and functional characteristics of reCG, a bioinformatics analysis was performed. An exhaustive characterization comprising the determination of the purity degree, aggregates and nicked forms through SDS-PAGE, RP-HPLC and SEC-HPLC was performed. Higher order structures were studied by fluorescence spectroscopy and SEC-HPLC. Isoforms profile were analyzed by isoelectric focusing. Glycosylation analysis was performed through pulsed amperometric detection and PNGase F treatment following SDS-PAGE and weak anion exchange-HPLC. Slight differences between the purified recombinant hormones were found. However, recombinant molecules and PMSG exhibited variations in the glycosylation pattern. In fact, differences in sialic acid content between two commercial preparations of PMSG were also obtained, which could lead to differences in their biological potency. These results show the importance of having a standardized production process, as occurs in a recombinant protein bioprocess. Besides, our results reflect the importance of the glycan moieties on eCG conformation and hence in its biological activity, preventing denaturing processes such as aggregation.