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1.
Sci Rep ; 14(1): 844, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191651

RESUMO

Steroidogenesis of gonadal cells is tightly regulated by gonadotropins. However, certain polycyclic aromatic hydrocarbons, including Benzo[a]pyrene (BaP), induce reproductive toxicity. Several existing studies have considered higher than environmentally relevant concentrations of BaP on male and female steroidogenesis following long-term exposure. Also, the impact of short-term exposure to BaP on gonadotropin-stimulated cells is understudied. Therefore, we evaluated the effect of 1 nM and 1 µM BaP on luteinizing hormone/choriogonadotropin (LH/hCG)-mediated signalling in two steroidogenic cell models, i.e. the mouse tumor Leydig cell line mLTC1, and the human primary granulosa lutein cells (hGLC) post 8- and 24-h exposure. Cell signalling studies were performed by homogeneous time-resolved fluorescence (HTRF) assay, bioluminescence energy transfer (BRET) and Western blotting, while immunostainings and immunoassays were used for intracellular protein expression and steroidogenesis analyses, respectively. BaP decreased cAMP production in gonadotropin-stimulated mLTC1 interfering with Gαs activation. Therefore, decrease in gonadotropin-mediated CREB phosphorylation in mLTC1 treated with 1 µM BaP was observed, while StAR protein levels in gonadotropin-stimulated mLTC1 cells were unaffected by BaP. Further, BaP decreased LH- and hCG-mediated progesterone production in mLTC1. Contrastingly, BaP failed to mediate any change in cAMP, genes and proteins of steroidogenic machinery and steroidogenesis of gonadotropin-treated hGLC. Our results indicate that short-term exposure to BaP significantly impairs steroidogenic signalling in mLTC1 interfering with Gαs. These findings could have a significant impact on our understanding of the mechanism of reproductive toxicity by endocrine disruptors.


Assuntos
Benzo(a)pireno , Células Intersticiais do Testículo , Humanos , Animais , Camundongos , Feminino , Masculino , Benzo(a)pireno/toxicidade , Gonadotropina Coriônica/farmacologia , Bioensaio , Western Blotting
2.
Cells ; 12(11)2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37296657

RESUMO

Bisphenol A (BPA) is a ubiquitous, synthetic chemical proven to induce reproductive disorders in both men and women. The available studies investigated the effects of BPA on male and female steroidogenesis following long-term exposure to the compound at relatively high environmental concentrations. However, the impact of short-term exposure to BPA on reproduction is poorly studied. We evaluated if 8 and 24 h exposure to 1 nM and 1 µM BPA perturbs luteinizing hormone/choriogonadotropin (LH/hCG)-mediated signalling in two steroidogenic cell models, i.e., the mouse tumour Leydig cell line mLTC1, and human primary granulosa lutein cells (hGLC). Cell signalling studies were performed using a homogeneous time-resolved fluorescence (HTRF) assay and Western blotting, while gene expression analysis was carried out using real-time PCR. Immunostainings and an immunoassay were used for intracellular protein expression and steroidogenesis analyses, respectively. The presence of BPA leads to no significant changes in gonadotropin-induced cAMP accumulation, alongside phosphorylation of downstream molecules, such as ERK1/2, CREB and p38 MAPK, in both the cell models. BPA did not impact STARD1, CYP11A1 and CYP19A1 gene expression in hGLC, nor Stard1 and Cyp17a1 expression in mLTC1 treated with LH/hCG. Additionally, the StAR protein expression was unchanged upon exposure to BPA. Progesterone and oestradiol levels in the culture medium, measured by hGLC, as well as the testosterone and progesterone levels in the culture medium, measured by mLTC1, did not change in the presence of BPA combined with LH/hCG. These data suggest that short-term exposure to environmental concentrations of BPA does not compromise the LH/hCG-induced steroidogenic potential of either human granulosa or mouse Leydig cells.


Assuntos
Hormônio Luteinizante , Progesterona , Camundongos , Animais , Feminino , Humanos , Masculino , Progesterona/metabolismo , Testosterona , Fenóis/toxicidade
3.
Endocrine ; 81(2): 330-339, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37140814

RESUMO

PURPOSE: To clarify the relationship between one the most gender-specific hormone, i.e. prolactin (PRL), and semen parameters in men. METHODS: A retrospective, observational, cohort, real-world study was carried out, enrolling all men performing a semen analysis and PRL examination from 2010 to 2022. For each patient, the first semen analys was extracted, associated to PRL, total testosterone (TT), follicle stimulating hormone (FSH) and luteinizing hormone (LH). Hyperprolactinaemia (>35 ng/mL) was excluded. RESULTS: 1211 subjects were included. PRL serum levels were lower in normozoospermia compared to azoospermia (p = 0.002) and altered semen parameters (p = 0.048) groups. TT serum levels were not different among groups (p = 0.122). Excluding azoospermic men, PRL serum levels were lower in normozoospermic patients, when compared to other groups of semen alterations. An inverse correlation was detected between PRL and sperm concentration. Considering normozospermic subjects, PRL was directly related to both non-progressive sperm motility (p = 0.014) and normal sperm morphology (p = 0.040). Subdiving the cohort in quartiles according to PRL distribution, the highest motilities were observed in the second PRL quartile (8.30-11.10 ng/mL) and asthenozoospermia was significantly predicted by FSH (p < 0.001) and second PRL quartile (p = 0.045). CONCLUSION: The PRL-spermatogenesis connection seems to be mild, although low-normal PRL levels are associated with the best spermatogenetic profile. PRL serum levels could mirror the immunoregulatory status within the testis, suggesting that there is a sort of 'PRL optimal window' reflecting an efficent spermatogenesis. Alternatively, men with good semen parameters might have a higher central dopaminergic tone resulting in low PRL levels.


Assuntos
Prolactina , Espermatogênese , Humanos , Masculino , Estudos Retrospectivos , Estudos de Coortes , Prolactina/sangue , Prolactina/metabolismo , Sêmen/química
5.
Mol Hum Reprod ; 26(12): 894-905, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33084890

RESUMO

Commercial hMG drugs are marketed for the treatment of infertility and consist of highly purified hormones acting on receptors expressed in target gonadal cells. Menopur® and Meriofert® are combined preparation of FSH and hCG and are compared in vitro herein. To this purpose, the molecular composition of the two drugs was analyzed by immunoassay. The formation of FSH receptor and LH/hCG receptor (FSHR; LHCGR) heteromer, intracellular Ca2+ and cAMP activation, ß-arrestin 2 recruitment and the synthesis of progesterone and estradiol were evaluated in transfected HEK293 and human primary granulosa lutein cells treated by drugs administered within the pg-mg/ml concentration range. Molecular characterization revealed that Meriofert® has a higher FSH:hCG ratio than Menopur® which, in turn, displays the presence of LH molecules. While both drugs induced similar FSHR-LHCGR heteromeric formations and intracellular Ca2+ increase, Meriofert® had a higher potency than Menopur® in inducing a cAMP increase. Moreover, Meriofert® revealed a higher potency than Menopur® in recruiting ß-arrestin 2, likely due to different FSH content modulating the tridimensional structure of FSHR-LHCGR-ß-arrestin 2 complexes, as evidenced by a decrease in bioluminescence resonance energy transfer signal. This drug-specific activation of intracellular signaling pathways is consistent with the molecular composition of these preparations and impacts downstream progesterone and estradiol production, with Menopur® more potent than Meriofert® in inducing the synthesis of both the steroids. These findings are suggestive of distinct in-vivo activities of these preparations, but require cautious interpretation and further validation from clinical studies.


Assuntos
Gonadotropinas/metabolismo , Menopausa/fisiologia , Cálcio/metabolismo , Gonadotropina Coriônica/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Células HEK293 , Humanos , Imunoensaio , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
6.
Adv Clin Exp Med ; 28(2): 219-222, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30507073

RESUMO

BACKGROUND: Post-thrombotic intracerebral hemorrhage (ICH) is experienced by 6-8% of stroke patients and is associated with multiple factors, including acquired coagulopathy induced by the thrombolytic drug. OBJECTIVES: The objective of this study was to assess the outcome of the intravenous (IV) administration of fibrinogen concentrate in a series of acute stroke patients who developed iatrogenic fibrinogen critical depletion after IV thrombolysis. MATERIAL AND METHODS: Of the 39 ischemic stroke patients treated with IV thrombolysis with a severe hypofibrinogenemia requiring infusion with IV fibrinogen concentrate, 30 patients were treated with 2 g of IV recombinant tissue plasminogen activator (rt-PA), followed by further doses until the fibrinogen level reached 200 mg/dL in hemorrhagic patients or 100 mg/dL in non-hemorrhagic patients, and 9 were treated with IV rt-PA followed by endovascular thrombectomy. RESULTS: Preand post-thrombolysis National Institutes of Health Stroke Scale (NIHSS) scores were statistically different for the Cochran-Mantel-Haenszel test overall (p = 0.0002), at 24-hour evaluation (p = 0.0455) and at 7-day assessment (p = 0.0006). Within the first 7 days post-thrombolysis, the brain computed tomography (CT) scans showed that 20/39 (51.28%) patients had ICH. Of the whole sample, 25.6% of the ICH patients had symptomatic intracerebral hemorrhage (SICH), according to National Institute of Neurological Disorders and Stroke (NINDS) classification. After rt-PA treatment, the median pre-thrombolysis fibrinogenemia of 332 mg/dL significantly dropped to 133 mg/dL (p < 0.0001). After the fibrinogen concentrate infusion, the median level of fibrinogenemia rose to 160 mg/dL, which was significantly higher than the median postthrombolysis levels (p < 0.0001). Recanalization was observed in 25/28 patients (89.29%): complete in 18 and partial in 7 patients. After fibrinogen IV infusion, no thrombotic complications were seen in 37 out of 39 patients (94.77%); 2/39 (0.05%) patients experienced a pulmonary embolism, 1 of them a segmental one. CONCLUSIONS: This study showed the clinical safety of administering IV fibrinogen concentrate in order to increase plasma fibrinogen levels in a series of acute stroke patients with iatrogenic fibrinogen depletion after IV thrombolysis.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fibrinogênio/análise , Fibrinolíticos/efeitos adversos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos , Administração Intravenosa , Isquemia Encefálica/sangue , Fibrinolíticos/administração & dosagem , Fibrinolíticos/sangue , Humanos , Acidente Vascular Cerebral/sangue , Fatores de Tempo , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
8.
Artigo em Inglês | MEDLINE | ID: mdl-29184537

RESUMO

PURPOSE: The relationship between probiotics and levothyroxine (LT4) requirement has not yet been investigated. The aim of this study was to assess whether a mixture of highly charged Lactobacilli and Bifidobacteria (VSL#3®) is able to influence LT4 metabolism acting on the gut microbiota. METHODS: A prospective, randomized, single-blind, controlled, investigator-started clinical trial was carried out. Patients with primary hypothyroidism were randomly assigned to the study (VSL#3® + LT4) and the control group (LT4). A 2-month treatment phase was followed by 2 months of follow-up. Clinical examination, blood tests for thyroid function and for peripheral tissue markers of thyroid hormones (PTM) were performed monthly. LT4 dose adjustments were performed when necessary. RESULTS: Thirty-nine patients were enrolled in the study group and 41 in the control group. No difference in thyroid function [thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4)] and PTM was found between groups and among visits. FT3/fT4 ratio was directly correlated to TSH at each visit in both groups, with the exception of the first evaluation of probiotics-treated subjects (rho = 0.287, p = 0.076). LT4 daily dose adjustments occurred more frequently in the control than in the study group (p = 0.007), despite no differences in the mean LT4 daily dose. In particular, LT4 doses were increased six times in the control group and decreased four times in the study group. CONCLUSION: VSL#3® does not directly alter thyroid functional compensation. A probiotics-mediated influence on thyroid hormones homeostasis is suggested since probiotics supplementation could be able to prevent serum hormonal fluctuations. CLINICALTRIALSGOV ID: Registration number NCT03095963.

9.
Mol Hum Reprod ; 23(10): 685-697, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29044421

RESUMO

STUDY QUESTION: Are four urinary hCG/menotropin (hMG) and one recombinant preparation characterized by different molecular features and do they mediate specific intracellular signaling and steroidogenesis? SUMMARY ANSWER: hCG and hMG preparations have heterogeneous compositions and mediate preparation-specific cell signaling and early steroidogenesis, although similar progesterone plateau levels are achieved in 24 h-treated human primary granulosa cells in vitro. WHAT IS KNOWN ALREADY: hCG is the pregnancy hormone marketed as a drug for ARTs to induce final oocyte maturation and ovulation, and to support FSH action. Several hCG formulations are commercially available, differing in source, purification methods and biochemical composition. STUDY DESIGN, SIZE, DURATION: Commercial hCG preparations for ART or research purposes were compared in vitro. PARTICIPANTS/MATERIALS, SETTING, METHODS: The different preparations were quantified by immunoassay with calibration against the hCG standard (Fifth IS; NIBSC 07/364). Immunoreactivity patterns, isoelectric points and oligosaccharide contents of hCGs were evaluated using reducing and non-reducing Western blotting, capillary isoelectric-focusing immunoassay and lectin-ELISA, respectively. Functional studies were performed in order to evaluate intracellular and total cAMP, progesterone production and ß-arrestin 2 recruitment by ELISA and BRET, in both human primary granulosa lutein cells (hGLC) and luteinizing hormone (LH)/hCG receptor (LHCGR)-transfected HEK293 cells, stimulated by increasing hormone concentrations. Statistical analysis was performed using two-way ANOVA and Bonferroni post-test or Mann-Whitney's U-test as appropriate. MAIN RESULTS AND THE ROLE OF CHANCE: Heterogeneous profiles were found among preparations, revealing specific molecular weight patterns (20-75 KDa range), isoelectric points (4.0-9.0 pI range) and lectin binding (P < 0.05; n = 7-10). These drug-specific compositions were linked to different potencies on cAMP production (EC50 1.0-400.0 ng/ml range) and ß-arrestin 2 recruitment (EC50 0.03-2.0 µg/ml) in hGLC and transfected HEK293 cells (P < 0.05; n = 3-5). In hGLC, these differences were reflected by preparation-specific 8-h progesterone production although similar plateau levels of progesterone were acheived by 24-h treatment (P ≥ 0.05; n = 3). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The biological activity of commercial hCG/hMG preparations is provided in International Units (IU) by in-vivo bioassay and calibration against an International Standard, although it is an unsuitable unit of measure for in-vitro studies. The re-calibration against recombinant hCG,quantified in grams, is based on the assumption that all of the isoforms and glycosylation variants have similar immunoreactivity. WIDER IMPLICATIONS OF THE FINDINGS: hCG/hMG preparation-specific cell responses in vitro may be proposed to ART patients affected by peculiar ovarian response, such as that caused by polycystic ovary syndrome. Otherwise, all the preparations available for ART may provide a similar clinical outcome in healthy women. STUDY FUNDING AND COMPETING INTEREST(S): This study was supported by a grant of the Italian Ministry of Education, University and Research (PRIN 2015XCR88M). The authors have no conflict of interest.


Assuntos
Gonadotropina Coriônica/química , Fármacos para a Fertilidade Feminina/química , Células da Granulosa/efeitos dos fármacos , Menotropinas/química , Progesterona/biossíntese , Transdução de Sinais/efeitos dos fármacos , Adulto , Gonadotropina Coriônica/farmacologia , AMP Cíclico/biossíntese , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Hormônio Foliculoestimulante/genética , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Células HEK293 , Humanos , Ponto Isoelétrico , Fase Luteal/fisiologia , Menotropinas/farmacologia , Peso Molecular , Indução da Ovulação/métodos , Gravidez , Cultura Primária de Células , Receptores do LH/genética , Receptores do LH/metabolismo , Transfecção , beta-Arrestina 2/genética , beta-Arrestina 2/metabolismo
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