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1.
Cell Calcium ; 122: 102908, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38852333

RESUMO

Animal and human studies have suggested that sex steroids have calciotropic actions, and it has been proposed that follicle-stimulating hormone (FSH) may exert direct effects on bone. Here, we demonstrate the expression of the receptor for Luteinizing hormone (LH) and human choriogonadotropin (hCG), LHCGR, in human kidney tissue, suggesting a potential influence on calcium homeostasis. To investigate the role of LHCGR agonist on calcium homeostasis in vivo, we conducted studies in male mice and human subjects. Male mice were treated with luteinizing hormone (LH), and human extrapolation was achieved by injecting 5000 IU hCG once to healthy men or men with hypergonadotropic or hypogonadotropic hypogonadism. In mice, LH treatment significantly increased urinary calcium excretion and induced a secondary increase in serum parathyroid hormone (PTH). Similarly, hCG treatment in healthy men led to a significant increase in urinary calcium excretion, serum PTH levels, and 1,25 (OH)2D3, while calcitonin, and albumin levels were reduced, possibly to avoid development of persistent hypocalcemia. Still, the rapid initial decline in ionized calcium coincided with a significant prolongation of the cardiac QTc-interval that normalized over time. The observed effects may be attributed to LH/hCG-receptor (LHCGR) activation, considering the presence of LHCGR expression in human kidney tissue, and the increase in sex steroids occurred several hours after the changes in calcium homeostasis. Our translational study shed light on the intricate relationship between gonadotropins, sex hormones and calcium, suggesting that LHCGR may be influencing calcium homeostasis directly or indirectly.

2.
Environ Int ; 183: 108383, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38109833

RESUMO

BACKGROUND: Many endocrine disrupting chemicals (EDCs), for instance phthalates and benzophenones, are associated with adverse fertility outcomes and semen quality parameters. OBJECTIVE: To evaluate if concentrations of selected phthalate metabolites and benzophenones measured in follicular fluid are associated with fertility outcomes (i.e., reproductive hormones, antral follicle count, detected heartbeat at gestational week 7, and live birth) and, in a supplementary study, if measured concentrations of chemicals in follicular fluid can exert biological effects on human spermatozoa. METHODS: Overall, 111 couples from a fertility clinic in Denmark contributed with 155 follicular fluid samples. Concentrations of 43 metabolites from 19 phthalates and phthalate substitutes and six benzophenones were measured in follicular fluid using liquid chromatography-tandem mass spectrometry. Multiple linear and logistic regression with an applied generalized estimating equation model allowing more than one measurement per woman assessed the association between follicular EDC levels and fertility outcomes. The assessment of biological effects of individual and mixtures of EDCs on human spermatozoa was conducted through a human sperm cell based Ca2+-fluorimetric assay. RESULTS: Benzophenone-3 (BP-3) and seven metabolites of five phthalates were detectable in follicular fluid. Women with metabolites of dibutyl phthalate isomers in the highest tertiles had lower antral follicle count (MiBP: ß = -5.35 [95 % CI: -9.06; -2.00], MnBP: ß = -5.25 [95 % CI: -9.00; -2.00]) and lower odds for detecting a heartbeat at gestational week 7 (MiBP: OR = 0.35 [95 % CI: 0.14; 0.91], MnBP: OR = 0.39 [95 % CI: 0.13; 1.15]). Mixtures of the measured concentrations of BP-3 and the seven phthalate metabolites induced a small significant increase in the intracellular calcium ion concentration in human spermatozoa from healthy donors (n = 3). DISCUSSION: Phthalate metabolites and BP-3 were detectable in follicular fluid and high concentrations of some phthalate metabolites were linked with lower chance of successful fertility treatment outcomes. Chemical mixture concentrations in follicular fluid induced a calcium response in human spermatozoa highlighting possible biological effects at physiologically relevant concentrations.


Assuntos
Disruptores Endócrinos , Poluentes Ambientais , Ácidos Ftálicos , Humanos , Masculino , Feminino , Líquido Folicular/metabolismo , Análise do Sêmen , Cálcio , Sêmen/metabolismo , Ácidos Ftálicos/metabolismo , Disruptores Endócrinos/metabolismo , Benzofenonas/metabolismo , Poluentes Ambientais/metabolismo
3.
Br J Cancer ; 127(3): 408-421, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35418213

RESUMO

BACKGROUND: Testicular germ cell tumours (TGCTs) have a high sensitivity to chemotherapy and a high cure rate, although with serious adverse effects. In the search for tumour suppressive drugs, the RANKL inhibitor Denosumab, used to treat osteoporosis, came up as a candidate since RANKL signalling was recently identified in the testis. METHODS: Expression of RANKL, RANK and OPG, and the effects of RANKL inhibition were investigated in human TGCTs, TGCT-derived cell-lines, and TGCT-xenograft models. Serum RANKL was measured in TGCT-patients. RESULTS: RANKL, RANK, and OPG were expressed in germ cell neoplasia in situ (GCNIS), TGCTs, and TGCT-derived cell lines. RANKL-inhibition reduced proliferation of seminoma-derived TCam-2 cells, but had no effect on embryonal carcinoma-derived NTera2 cells. Pretreatment with Denosumab did not augment the effect of cisplatin in vitro. However, inhibition of RANKL in vivo reduced tumour growth exclusively in the TCam-2-xenograft model and Denosumab-treatment decreased proliferation in human GCNIS cultures. In TGCT-patients serum RANKL had no prognostic value. CONCLUSIONS: This study shows that the RANKL signalling system is expressed in GCNIS and seminoma where RANKL inhibition suppresses tumour growth in vitro and in vivo. Future studies are needed to determine whether RANKL is important for the malignant transformation or transition from GCNIS to invasive tumours.


Assuntos
Neoplasias Embrionárias de Células Germinativas , Seminoma , Neoplasias Testiculares , Denosumab/farmacologia , Denosumab/uso terapêutico , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Seminoma/tratamento farmacológico , Seminoma/metabolismo , Neoplasias Testiculares/patologia
4.
Bone ; 154: 116244, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34757214

RESUMO

OBJECTIVE: Granuloma formation following self-administered cosmetic oil injections can lead to severe hypercalcemia and renal calcifications due to extra-renal vitamin D activation. This translational study aims to identify Prednisolone sparing therapeutics for hypercalcemia after development of granulomatous disease secondary to paraffin oil injections. MATERIALS AND METHODS: Granuloma tissue isolated from five men were cultured ex vivo and treated with selected drugs to block generation of activated vitamin D (1,25(OH)2D3). In a retrospective study, we included data before and during different treatments of 21 men with paraffin oil induced granulomatous hypercalcemia (46 treatment courses) where serum calcium, parathyroid hormone, vitamin D metabolites, creatinine and inflammatory markers were measured. RESULTS: Addition of Ketoconazole or Ciclosporin to granuloma tissue ex vivo culture, significantly suppressed production of 1,25(OH)2D3 after 48 h (both p < 0.05). Prednisolone was the first treatment option in most men and lowered serum levels of ionized calcium after 1, 2, 3 and 6 months compared with baseline (p < 0.05). Ketoconazole or Hydroxychloroquine had no significant effect on serum calcium levels and were unable to reduce the concomitant daily Prednisolone doses (p > 0.05). Azathioprine did not reduce calcium levels. However, addition of Tacrolimus to Prednisolone treatment enabled a reduction in Prednisolone dose after 3 months (p = 0.014), but with no additional effect on calcium homeostasis. CONCLUSION: This study verifies that Prednisolone is an effective treatment and suggests that calcineurin inhibitors may be used as Prednisolone sparing treatment for paraffin oil-induced granulomatous hypercalcemia. Randomized clinical trials are needed to determine clinical efficacy.


Assuntos
Hipercalcemia , Cálcio , Humanos , Hipercalcemia/induzido quimicamente , Hipercalcemia/tratamento farmacológico , Masculino , Hormônio Paratireóideo , Projetos Piloto , Estudos Retrospectivos , Vitamina D/uso terapêutico
5.
J Endocrinol ; 251(3): 207-222, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34612843

RESUMO

Vitamin D is important for gonadal function in rodents, and improvement of vitamin D status in men with low sperm counts increases live birth rate. Vitamin D is a regulator of transcellular calcium transport in the intestine and kidney and may influence the dramatic changes in the luminal calcium concentration in epididymis. Here, we show spatial expression in the male reproductive tract of vitamin D receptor (VDR)-regulated factors involved in calcium transport: transient receptor potential vanilloid 5/6 , sodium/calcium exchanger 1, plasma membrane calcium ATPase 1, calbindin D9k, calcium-sensing receptor (CaSR), and parathyroid hormone-related peptide (PTHrP) in mouse and human testis and epididymis. Testicular Casr expression was lower in Vdr ablated mice compared with controls. Moreover, expression levels of Casr and Pthrp were strongly correlated in both testis and epididymis and Pthrp was suppressed by 1,25(OH)2D3 in a spermatogonial cell line. The expression of CaSR in epididymis may be of greater importance than in the gonad in mice as germ cell-specific Casr deficient mice had no major reproductive phenotype, and coincubation with a CaSR-agonist had no effect on human sperm-oocyte binding. In humans, seminal calcium concentration between 5 and 10 mM was associated with a higher fraction of motile and morphologically normal sperm cells, and the seminal calcium concentration was not associated with serum calcium levels. In conclusion, VDR regulates CaSR and PTHrP, and both factors may be involved in the regulation of calcium transport in the male reproductive tract with possible implications for sperm function and storage.


Assuntos
Cálcio/metabolismo , Epididimo/metabolismo , Receptores de Calcitriol/metabolismo , Receptores de Detecção de Cálcio/metabolismo , Testículo/metabolismo , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteína Relacionada ao Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Receptores de Detecção de Cálcio/genética , Proteína G de Ligação ao Cálcio S100/genética , Proteína G de Ligação ao Cálcio S100/metabolismo , Sêmen , Trocador de Sódio e Cálcio/genética , Trocador de Sódio e Cálcio/metabolismo , Interações Espermatozoide-Óvulo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
6.
Cancers (Basel) ; 13(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809538

RESUMO

Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) are agonists for the luteinizing hormone receptor (LHCGR) which regulates male reproductive function. LHCGR may be released into body fluids. We wish to determine whether soluble LHCGR is a marker for gonadal function. Cross-sectional, longitudinal, and intervention studies on 195 healthy boys and men and 396 men with infertility, anorchia, or Klinefelter Syndrome (KS) were used to correlate LHCGR measured in serum, seminal fluid, urine, and hepatic/renal artery and vein with gonadal function. LHCGR was determined in fluids from in vitro and in vivo models of human testicular tissue and cell lines, xenograft mouse models, and human fetal kidney and adrenal glands. Western blot showed LHCGR fragments in serum and gonadal tissue of similar size using three different antibodies. The LHCGR-ELISA had no species cross-reactivity or unspecific reaction in mouse serum even after human xenografting. Instead, sLHCGR was released into the media after the culture of a human fetal kidney and adrenal glands. Serum sLHCGR decreased markedly during puberty in healthy boys (p = 0.0001). In healthy men, serum sLHCGR was inversely associated with the Inhibin B/FSH ratio (ß -0.004, p = 0.027). In infertile men, seminal fluid sLHCGR was inversely associated with serum FSH (ß 0.006, p = 0.009), sperm concentration (ß -3.5, p = 0.003) and total sperm count (ß -3.2, p = 0.007). The injection of hCG lowered sLHCGR in serum and urine of healthy men (p < 0.01). In conclusion, sLHCGR is released into body-fluids and linked with pubertal development and gonadal function. Circulating sLHCGR in anorchid men suggests that sLHCGR in serum may originate from and possibly exert actions in non-gonadal tissues. (ClinicalTrials: NTC01411527, NCT01304927, NCT03418896).

7.
J Bone Miner Res ; 36(2): 322-333, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32931047

RESUMO

Intramuscular injections of paraffin oil can cause foreign body granuloma formation and hypercalcemia. Macrophages with the ability to produce high levels of 1,25(OH)2 D3 may induce the mineral disturbance, but no major series of patients have been published to date. Here, medical history, physical evaluation, biochemical, and urinary analysis for calcium homeostasis were obtained from 88 males, who 6 years previously had injected paraffin or synthol oil into skeletal muscle. Moreover, granuloma tissue from three men was cultured for 48 hours ex vivo to determine 1,25(OH)2 D3 production supported by qPCR and immunohistochemistry of vitamin D metabolism and immune cell populations after treatment with 14 different drugs. The 88 men were stratified into men with hypercalcemia (34%), whereas normocalcemic men were separated into men with either normal (42%) or suppressed parathyroid hormone (PTH) (24%). All men had high calcium excretion, and nephrolithiasis was found in 48% of hypercalcemic men, 22% of normocalcemic men with normal PTH, and 47% of normocalcemic men with suppressed PTH. Risk factors for developing hypercalcemia were oil volume injected, injection of heated oil, high serum interleukin-2 receptor levels, and high urine calcium. High 1,25(OH)2 D3 /25OHD ratio, calcium excretion, and low PTH was associated with nephrolithiasis. The vitamin D activating enzyme CYP27B1 was markedly expressed in granuloma tissue, and 1,25(OH)2 D3 was released in concentrations corresponding to 40% to 50% of the production by human kidney specimens. Dexamethasone, ketoconazole, and ciclosporin significantly suppressed granulomatous production of 1,25(OH)2 D3 . In conclusion, this study shows that injection of large oil volumes alters calcium homeostasis and increases the risk of nephrolithiasis. Hypercalciuria is an early sign of disease, and high granulomatous 1,25(OH)2 D3 production is part of the cause. Prospective clinical trials are needed to determine if ciclosporin, ketoconazole, or other drugs can be used as prednisolone-sparing treatment. © 2020 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Hipercalcemia , Cálcio , Humanos , Hipercalcemia/induzido quimicamente , Hipercalciúria , Masculino , Hormônio Paratireóideo , Estudos Prospectivos , Vitamina D
8.
Cancers (Basel) ; 12(6)2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32466562

RESUMO

Luteinizing hormone/choriogonadotropin receptor (LHCGR) regulates gonadal testosterone production and recent studies have suggested a growth-regulatory role in somatic cancers. Here, we established that LHCGR is expressed in a fraction of seminoma cells and germ cell neoplasia in situ (GCNIS), and the seminoma-derived cell line TCam2 released LHCGR into the medium. LH treatment induced proliferation of TCam2 cells in vitro, while hCG treatment induced a non-significant 51% increase in volume of tumors formed in a TCam2 xenograft model. A specific ELISA was used to detect a soluble LHCGR in serum. Serum concentrations of soluble LHCGR could not distinguish 4 patients with GCNIS and 216 patients with testicular germ cell tumors (TGCTs) from 297 infertile or 148 healthy young men. Instead, serum LHCGR levels were significantly higher in 112 patients with a seminoma > 5 cm or elevated serum lactate dehydrogenase (LDH) compared with men harboring smaller seminomas < 2 cm or normal LDH levels. Serum LHCGR levels in TGCT patients could not predict relapse irrespective whether determined pre- or post-orchiectomy. Combined, these novel findings suggest that LHCGR may be directly involved in the progression and growth of seminomas, and our retrospective pilot study suggests that serum LHCGR may have some prognostic value in men with seminoma.

9.
J Steroid Biochem Mol Biol ; 191: 105353, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30965119

RESUMO

Male fertility is routinely evaluated by semen analysis, although semen quality variables such as; sperm count, motility and morphology have low predictive value for spontaneous pregnancies and fertility treatment outcomes. Vitamin D has been suggested to be beneficial for male reproduction. The vitamin D receptor and the vitamin D inactivating enzyme CYP24A1 are co-expressed in high quality sperm. Presence of CYP24A1 at the annulus of human sperm can distinguish between sperm from healthy and infertile men with high specificity and is positively correlated with semen quality. The high expression level in the testis of FAM57B2, which is activated by 24,25OH2D3, indicates an uncharacterized biological role for CYP24A1 in male reproduction. Moreover, activated vitamin D has been shown to induce sperm motility and promote fertilization in vitro. Here, we prospectively investigated whether the fraction of CYP24A1 positive sperm was a better predictor of clinical pregnancy than semen analysis by including 240 fertility treatments (169 couples) from a single fertility centre in Denmark. ROC-curve based analysis showed that the percentage of sperm expressing CYP24A1 was a better predictor of successful pregnancy outcome after intrauterine inseminations (IUI) than both sperm concentration and motility (p < 0.05). Interestingly, samples with CYP24A1 staining >67% of the sperm increased the likelihood of achieving pregnancy 4-fold after IUI compared with samples having fewer sperm with detectable CYP24A1 (p < 0.05). Neither CYP24A1 nor any of the other assessed semen quality variables were predictive for the treatment outcome of the more invasive assisted reproductive techniques (IVF and ICSI). In conclusion, our results provide proof of principle for a CYP24A1-based sperm test to improve fertility outcome for infertile patients referred for IUI and supports a role for vitamin D metabolites during fertilization.


Assuntos
Espermatozoides/citologia , Vitamina D3 24-Hidroxilase/análise , Adulto , Feminino , Fertilização in vitro , Humanos , Inseminação Artificial , Masculino , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/química
10.
Bone ; 123: 103-114, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30914274

RESUMO

INTRODUCTION: The FSH receptor (FSHR) has been found to be expressed in human bone cells and bone marrow-adipocytes, and highly-debated mouse studies have suggested extra-gonadal effects of gonadotropins on glucose, adipocyte and bone homeostasis. These putative effects could be direct or indirectly mediated by endocrine factors released from bone-cells or adipocytes. Here, we investigated whether gonadotropins are linked with glucose- and lipid-metabolism in hypergonadotropic men. METHODS: Single centre, cross-sectional study of 307 men with idiopathic infertility and 28 men with Klinefelter syndrome (KS). OUTCOME: associations between serum LH and FSH with soluble-RANKL (sRANKL), osteoprotegerin (OPG), osteocalcin, fasting glucose and insulin, sex steroids, and body composition. Expression of FSHR was studied in human-derived adipocyte-cell-models (hMADS, TERT-hWA) and FSH stimulation of RANKL expression and secretion in hMADS in vitro. RESULTS: Serum FSH was not directly linked with glucose- and lipid-metabolism. However, FSH was inversely associated with sRANKL in both infertile men and KS men (p = .023 and p = .012). Infertile men with elevated FSH (>11 U/L) had significantly lower sRANKL (p = .015). sRANKL was positively associated with fat percentage, fasting insulin, and glucose (all p < .05). Men with prediabetes had higher sRANKL (p = .021), but lower testosterone (p < .0001) and Inhibin B (p = .005). The FSHR was expressed in the investigated human derived adipocytes, and 3-6 h treatment with FSH markedly increased RANKL release (p < .05). CONCLUSION: KS and infertile men with prediabetes have low Inhibin B, and testosterone but elevated RANKL compared with non-prediabetic men despite comparable levels of serum gonadotropins. Serum FSH and sRANKL was inversely associated in both infertile and KS men, but the increased release of RANKL from FSH treated adipocytes suggest a direct effect of FSH on RANKL production in some tissues. Further studies are required to clarify whether FSH targets RANKL in the skeleton. ClinicalTrial_ID:NCT01304927.


Assuntos
Adipócitos/metabolismo , Hormônio Foliculoestimulante/metabolismo , Infertilidade Masculina/metabolismo , Síndrome de Klinefelter/metabolismo , Ligante RANK/metabolismo , Adipócitos/efeitos dos fármacos , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Coortes , Estudos Transversais , Hormônio Foliculoestimulante/farmacologia , Humanos , Infertilidade Masculina/complicações , Infertilidade Masculina/diagnóstico , Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/diagnóstico , Masculino
11.
Mol Cell Endocrinol ; 453: 103-112, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28342856

RESUMO

Vitamin D is a versatile hormone with several functions beyond its well-established role in maintenance of skeletal health and calcium homeostasis. The effects of vitamin D are mediated by the vitamin D receptor, which is expressed together with the vitamin D metabolizing enzymes in the reproductive tissues. The reproductive organs are therefore responsive to and able to metabolize vitamin D locally. The exact role remains to be clarified but several studies have suggested a link between vitamin D and production/release of reproductive hormones into circulation, which will be the main focus of this review. Current evidence is primarily based on small human association studies and rodent models. This highlights the need for randomized clinical trials, but also functional animal and human in vitro studies, and larger, prospective cohort studies are warranted. Given the high number of men and women suffering from reproductive problems and abnormal endocrinology research addressing the role of vitamin D in reproductive endocrinology may be of clinical importance.


Assuntos
Fertilidade/fisiologia , Genitália/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Reprodução/fisiologia , Vitamina D/metabolismo , Animais , Feminino , Humanos , Masculino , Camundongos , Modelos Animais , Ratos , Receptores de Calcitriol/metabolismo
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