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1.
Reprod Fertil Dev ; 31(8): 1395-1400, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31056083

RESUMEN

Reproduction is an important target of obesity complications, including adverse effects on spermatogenesis and steroidogenesis. Adipocytokines are key mediators in various complications of obesity. Our aim was to study the potential of adipocytokines to affect Sertoli cell function, which is crucial for spermatogenesis, and possibly link these findings to the observed attenuation of spermatogenesis in obese males. Testicular biopsies were obtained from healthy donors. Highly purified adult human Sertoli cells (HSCs) were isolated by fluorescence-activated cell sorting. Cells were cultured and exposed to different concentrations of adipocytokines (10-1000ngmL-1 ) for 2-7 days. Expression of selected Sertoli cell genes was quantified by quantitative polymerase chain reaction. Long-term treatment (7 days) of HSCs with higher concentrations of chemerin, irisin, nicotinamide phosphoribosyltransferase (Nampt), resistin and progranulin significantly suppressed FSH receptor expression (by 79%, 83%, 64%, 71% and 26% respectively; P P invitro , may negatively affect Sertoli cell maturation and retain these cells in a more prepubertal stage. This could negatively affect testis function and add to fertility problems in obese adults.

2.
Hum Reprod ; 33(9): 1677-1683, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30052981

RESUMEN

STUDY QUESTION: Does chemotherapy exposure (with or without alkylating agents) or primary diagnosis affect spermatogonial quantity in human prepubertal testicular tissue? SUMMARY ANSWER: Spermatogonial quantity is significantly reduced in testes of prepubertal boys treated with alkylating agent therapies or with hydroxyurea for sickle cell disease. WHAT IS KNOWN ALREADY: Cryopreservation of spermatogonial stem cells, followed by transplantation into the testis after treatment, is a proposed clinical option for fertility restoration in children. The key clinical consideration behind this approach is a sufficient quantity of healthy cryopreserved spermatogonia. However, since most boys with malignancies start therapy with agents that are not potentially sterilizing, they will have already received some chemotherapy before testicular tissue cryopreservation is considered. STUDY DESIGN, SIZE, DURATION: We examined histological sections of prepubertal testicular tissue to elucidate whether chemotherapy exposure or primary diagnosis affects spermatogonial quantity. Quantity of spermatogonia per transverse tubular cross-section (S/T) was assessed in relation to treatment characteristics and normative reference values in histological sections of paraffin embedded testicular tissue samples collected from 32 consecutive boy patients (aged 6.3 ± 3.8 [mean ± SD] years) between 2014 and 2017, as part of the NORDFERTIL study, and in 14 control samples (from boys aged 5.6 ± 5.0 [mean ± SD] years) from an internal biobank. PARTICIPANTS/MATERIALS, SETTING, METHODS: Prepubertal boys in Sweden, Finland and Iceland who were facing treatments associated with a very high risk of infertility, were offered the experimental procedure of testicular cryopreservation. Exclusion criteria were testicular volumes >10 ml and high bleeding or infection risk. There were 18 patients with a diagnosis of malignancy and 14 patients a non-malignant diagnosis. While 20 patients had the testicular biopsy performed 1-45 days after chemotherapy, 12 patients had not received any chemotherapy. In addition, 14 testicular tissue samples of patients with no reported testicular pathology, obtained from the internal biobank of the Department of Pathology at Karolinska University Hospital, were included as control samples in addition to reference values obtained from a recently published meta-analysis. The quantity of spermatogonia was assessed by both morphological and immunohistochemical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The main finding was a significant reduction in spermatogonial cell counts in boys treated with alkylating agents or with hydroxyurea for sickle cell disease. The mean S/T values in boys exposed to alkylating agents (0.2 ± 0.3, n = 6) or in boys with sickle cell disease and exposed to hydroxyurea (0.3 ± 0.6, n = 6) were significantly lower (P = 0.003 and P = 0.008, respectively) than in a group exposed to non-alkylating agents or in biobank control samples (1.7 ± 1.0, n = 8 and 4.1 ± 4.6, n = 14, respectively). The mean S/T values of the testicular tissue samples included in the biobank control group and the patient group exposed to non-alkylating agents were within recently published normative reference values. LIMITATIONS, REASONS FOR CAUTION: Normal testicular tissue samples included in this study were obtained from the internal biobank of Karolinska University Hospital. Samples were considered normal and included in the study if no testicular pathology was reported in the analysed samples. However, detailed information regarding previous medical treatments and testicular volumes of patients included in this biobank were not available. WIDER IMPLICATIONS OF THE FINDINGS: This study summarizes, for the first time, spermatogonial quantity in a prepubertal patient cohort just before and after potentially sterilizing treatments. Boys facing cancer and cytotoxic therapies are regarded as the major group who will benefit from novel fertility preservation techniques. There are no previous reports correlating spermatogonial quantity to cumulative exposure to alkylating agents and anthracyclines (non-alkylating agents) and no information about the timing of cytotoxic exposures among this particular patient cohort. For prepubertal boys in whom fertility preservation is indicated, testicular tissue should be obtained before initiation of chemotherapy with alkylating agents, whilst for those with sickle cell disease and treated with hydroxyurea, this approach to fertility preservation may not be feasible. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by grants from The Swedish Childhood Cancer Foundation (PR2016-0124; TJ2016-0093; PR2015-0073, TJ2015-0046) (J.-B.S. and K.J.), the Jane and Dan Olssons Foundation (2016-33) (J.-B.S.), the Finnish Cancer Society (K.J.), the Foundation for Paediatric Research (J.-B.S.), Kronprinsessan Lovisas Förening För Barnasjukvård/ Stiftelsen Axel Tielmans Minnesfond, Samariten Foundation (J.-B.S.), the Väre Foundation for Paediatric Cancer Research (K.J.) and the Swedish Research Council (2012-6352) (O.S.). R.T.M. was supported by a Wellcome Trust Fellowship (09822). J.P.A.-L. and M.K. were supported by the ITN Marie Curie program 'Growsperm' (EU-FP7-PEOPLE-2013-ITN 603568). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Antineoplásicos Alquilantes/efectos adversos , Hidroxiurea/efectos adversos , Espermatogonias/citología , Testículo/citología , Anemia de Células Falciformes/tratamiento farmacológico , Estudios de Casos y Controles , Niño , Preescolar , Estudios de Cohortes , Criopreservación , Preservación de la Fertilidad/métodos , Humanos , Masculino , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Radioterapia/efectos adversos
3.
Mol Hum Reprod ; 22(9): 601-12, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27430551

RESUMEN

STUDY QUESTION: Do the organ culture conditions, previously defined for in vitro murine male germ cell differentiation, also result in differentiation of rat spermatogonia into post-meiotic germ cells exhibiting specific markers for haploid germ cells? SUMMARY ANSWER: We demonstrated the differentiation of rat spermatogonia into post-meiotic cells in vitro, with emphasis on exhibiting, protein markers described for round spermatids. WHAT IS KNOWN ALREADY: Full spermatogenesis in vitro from immature germ cells using an organ culture technique in mice was first reported 5 years ago. However, no studies reporting the differentiation of rat spermatogonia into post-meiotic germ cells exhibiting the characteristic protein expression profile or into functional sperm have been reported. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: Organ culture of testicular fragments of 5 days postpartum (dpp) neonatal rats was performed for up to 52 days. Evaluation of microscopic morphology, testosterone levels, mRNA and protein expression as measured by RT-qPCR and immunostaining were conducted to monitor germ cell differentiation in vitro. Potential effects of melatonin, Glutamax® medium, retinoic acid and the presence of epidydimal fat tissue on the spermatogenic process were evaluated. A minimum of three biological replicates were performed for all experiments presented in this study. One-way ANOVA, ANOVA on ranks and student's t-test were applied to perform the statistical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Male germ cells, present in testicular tissue pieces grown from 5 dpp rats, exhibited positive protein expression for Acrosin and Crem (cAMP (cyclic adenosine mono phosphate) response element modulator) after 52 days of culture in vitro. Intra-testicular testosterone production could be observed after 3 days of culture, while when epididymal fat tissue was added, spontaneous contractility of cultured seminiferous tubules could be observed after 21 days. However, no supportive effect of the supplementation with any factor or the co-culturing with epididymal fat tissue on germ cell differentiation in vitro or testosterone production was observed. LIMITATIONS, REASONS FOR CAUTION: The human testis is very different in physiology from the rat testis, further investigations are still needed to optimize the organ culture system for future use in humans. WIDER IMPLICATIONS OF THE FINDINGS: The successful differentiation of undifferentiated spermatogonia using the testis explant culture system might be employed in future to produce sperm from human spermatogonia as a clinical tool for fertility preservation in boys and men suffering infertility. LARGE SCALE DATA: None. STUDY FUNDING AND COMPETING INTERESTS: This work was supported financially by the Frimurare Barnhuset in Stockholm, the Paediatric Research Foundation, Jeanssons Foundation, Sällskåpet Barnåvard in Stockholm, Swedish Research Council/Academy of Finland, Emil and Wera Cornells Foundation, Samariten Foundation, the Swedish Childhood Cancer Foundation as well as through the regional agreement on medical training and clinical research (ALF) between Stockholm County Council and Karolinska Institutet. All authors declare no conflicts of interests.


Asunto(s)
Diferenciación Celular/fisiología , Espermátides/citología , Espermatogénesis/fisiología , Espermatogonias/citología , Animales , Diferenciación Celular/genética , Preservación de la Fertilidad , Células Germinativas , Masculino , Meiosis/genética , Meiosis/fisiología , Ratas , Túbulos Seminíferos/citología , Túbulos Seminíferos/metabolismo , Espermátides/metabolismo , Espermatogénesis/genética , Espermatogonias/metabolismo , Testículo/citología , Testículo/metabolismo
4.
Horm Metab Res ; 48(9): 589-94, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27355242

RESUMEN

Insulin-like peptide 5 (INSL5) is a gut hormone produced by L-cells in the colorectal epithelium and may play a role in the regulation of metabolic processes. The biological role of INSL5 is poorly investigated and nothing is known about the role of this hormone in obese and lean humans. Two cohorts were analyzed in the study. In the first cohort (n=76) the relationship between serum levels of INSL5 and different metabolic and hormonal parameters in obese and lean men and women were investigated. In the second cohort 14 male subjects underwent bariatric surgery. Circulating levels of INSL5 were then measured before and after interventions.We report for the first time that circulating INSL5 interacts with multiple metabolic and hormonal variables in lean and obese men and women and is affected by bariatric surgery. Serum levels of INSL5 negatively correlated with testosterone and blood lipids but positively with cortisol in obese men. In contrast to males, obese women had a strong negative correlation of plasma levels of INSL5 with C-reactive protein (CRP). We observed that adipose tissue loss after bariatric surgery significantly reduced serum levels of INSL5 in obese men with and without Type 2 Diabetes Mellitus (T2DM) that was associated with the restoration of circulating levels of testosterone. All together, our data demonstrated that INSL5 may interact with some metabolic parameters in obese humans and this process is dependent of gender and obesity state.


Asunto(s)
Adiposidad , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Hormonas Esteroides Gonadales/metabolismo , Insulina/metabolismo , Síndrome Metabólico/metabolismo , Obesidad/complicaciones , Proteínas/metabolismo , Delgadez/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Estudios de Cohortes , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Síndrome Metabólico/etiología , Síndrome Metabólico/patología , Persona de Mediana Edad , Obesidad/fisiopatología , Pronóstico , Delgadez/fisiopatología , Adulto Joven
5.
Hum Reprod ; 30(2): 256-67, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25505010

RESUMEN

STUDY QUESTION: Is it possible to derive a scaffold from human testis for the purpose of tissue engineering and regenerative medicine? SUMMARY ANSWER: We developed a method to produce a cytocompatible decellularized testicular matrix (DTM) while maintaining the native tissue-specific characteristics and components. WHAT IS KNOWN ALREADY: The potential benefits of tissue-specific scaffolds consisting of naturally-derived extracellular matrix (ECM) have been demonstrated using a wide variety of animal and human tissue sources. However, so far, testis scaffolds have never been considered for constructive remodelling purposes. STUDY DESIGN, SIZE, DURATION: Human cadaveric testicular tissue was exposed for 24 or 48 h to 1% Triton X-100 and/or 1% sodium dodecyl sulphate (SDS). Acellular samples were used for further scaffold characterization purposes. PARTICIPANTS/MATERIALS, SETTING, METHODS: The extent of decellularization was evaluated by histology. Confirmation of cell removal in DTM was done by a DNA quantification technique. Retention of testicular tissue-specific characteristics was evaluated by mass spectrometry, immunohistochemistry, Alcian blue staining and scanning electron microscopy. Soluble toxicity and testicular cell attachment was assessed to check the cytocompatibility of DTM scaffolds. MAIN RESULTS AND THE ROLE OF CHANCE: Histological analysis showed that DTM could be obtained by mechanical agitation in 1% SDS for 24 h. The resulting DTM was found to be clear of cells while retaining the typical three-dimensional structure and the major components of the native tissue scaffold, including collagen type I and IV, fibronectin, laminin and glycosaminoglycans. In addition, using proteomic analysis, we revealed numerous additional ECM proteins in DTM, indicating its complex nature. The mass spectrometry data were deposited to the ProteomeXchange with identifier PXD001524. Importantly, we demonstrated that DTM scaffolds are not cytotoxic, as evidenced by MTT assay not showing an aberrant fibroblast proliferation activity after indirect exposure, and support testicular cell attachment and infiltration. LIMITATIONS, REASONS FOR CAUTION: The functionality of human testicular cells in DTM needs to be investigated. WIDER IMPLICATIONS OF THE FINDINGS: Our results suggest that the insights into the molecular composition of the testicular ECM provide new clues for the unravelling of its important yet poorly understood role in regulating testicular function, and DTM-based bioscaffolds are promising components for the development of human in vitro spermatogenesis as a treatment for various types of male fertility disorders.


Asunto(s)
Matriz Extracelular/química , Medicina Regenerativa/métodos , Testículo/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Bélgica , Cadáver , Adhesión Celular , Proliferación Celular , Células Cultivadas , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestructura , Proteínas de la Matriz Extracelular/metabolismo , Humanos , Inmunohistoquímica , Masculino , Microscopía Electrónica de Rastreo , Orquiectomía , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Proteómica/métodos , Piel/citología , Testículo/metabolismo , Testículo/patología , Testículo/ultraestructura , Células Tumorales Cultivadas
6.
Acta Paediatr ; 101(3): 292-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22040370

RESUMEN

AIM: To provide growth charts for clinical monitoring of extra-uterine growth from birth to full-term age, in infants born before 26 weeks of gestation, hospitalized at neonatal intensive care unit (NICU), and compare it to the commonly used Swedish preterm birth-size reference. METHODS: This retrospective longitudinal cohort comprised all infants born before 26 + 0 weeks of gestation and surviving to full-term age (n = 162), admitted to the NICU, Karolinska Hospital during the period January 1990 to December 2002. Body weight was recorded daily, head circumference (HC) weekly and length twice a month. RESULTS: Birth weight (BW), length and HC showed a normal distribution without significant gender difference. The majority of the infants showed a pronounced postnatal growth restriction for all growth variables with increasing deviation from the reference with age. The mean initial weight loss was 16% with nadir at 6 days of age and a mean time to regain BW of 18 days. At discharge from NICU, 75% of those initially appropriate for gestational age infants were below -2 standard deviation scores for at least one of the body size variables. CONCLUSION: The poor extra-uterine growth pattern points to the need of growth curves for extra-uterine growth of extremely premature infants.


Asunto(s)
Gráficos de Crecimiento , Recien Nacido Prematuro/crecimiento & desarrollo , Estatura , Peso Corporal , Femenino , Edad Gestacional , Cabeza/crecimiento & desarrollo , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Estudios Longitudinales , Masculino , Modelos Estadísticos , Estudios Retrospectivos , Suecia
8.
Artículo en Inglés | MEDLINE | ID: mdl-20862379

RESUMEN

During the past decades, a large body of information concerning the effects of endocrine disrupting compounds (EDCs) on animals and humans has been accumulated. EDCs are of synthetic or natural origin and certain groups are known to disrupt the action of androgens and to impair the development of the male reproductive tract and external genitalia. The present overview describes the effects of the different classes of EDCs, such as pesticides, phthalates, dioxins, and phytoestrogens, including newly synthesized resveratrol analogs on steroidogenesis in Leydig cells. The potential impact of these compounds on androgen production by Leydig cells during fetal development and in the adult age is discussed. In addition, the possible role of EDCs in connection with the increasing frequency of abnormalities in reproductive development in animals and humans is discussed.


Asunto(s)
Disruptores Endocrinos , Sistema Endocrino/efectos de los fármacos , Contaminantes Ambientales , Antagonistas de Hormonas/farmacología , Células Intersticiales del Testículo/fisiología , Adulto , Animales , Disruptores Endocrinos/efectos adversos , Sistema Endocrino/embriología , Sistema Endocrino/fisiología , Contaminantes Ambientales/toxicidad , Hormonas/fisiología , Humanos , Masculino , Reproducción/efectos de los fármacos , Maduración Sexual/efectos de los fármacos
9.
J Cell Biol ; 117(3): 629-41, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1315318

RESUMEN

beta-Nerve growth factor (NGF) is expressed in spermatogenic cells and has testosterone-downregulated low-affinity receptors on Sertoli cells suggesting a paracrine role in the regulation of spermatogenesis. An analysis of the stage-specific expression of NGF and its low affinity receptor during the cycle of the seminiferous epithelium in the rat revealed NGF mRNA and protein at all stages of the cycle. Tyrosine kinase receptor (trk) mRNA encoding an essential component of the high-affinity NGF receptor was also present at all stages. In contrast, expression of low affinity NGF receptor mRNA was only found in stages VIIcd and VIII of the cycle, the sites of onset of meiosis. The low-affinity NGF receptor protein was present in the plasma membrane of the apical Sertoli cell processes as well as in the basal plasma membrane of these cells at stages VIIcd to XI. NGF was shown to stimulate in vitro DNA synthesis of seminiferous tubule segments with preleptotene spermatocytes at the onset of meiosis while other segments remained nonresponsive. We conclude that NGF is a meiotic growth factor that acts through Sertoli cells.


Asunto(s)
Meiosis/fisiología , Factores de Crecimiento Nervioso/biosíntesis , Receptores de Superficie Celular/biosíntesis , Epitelio Seminífero/metabolismo , Animales , Diferenciación Celular/fisiología , Membrana Celular/química , Polaridad Celular , ADN/biosíntesis , Inmunohistoquímica , Masculino , Microscopía Inmunoelectrónica , ARN Mensajero/biosíntesis , Ratas , Ratas Endogámicas , Receptores de Factor de Crecimiento Nervioso , Células de Sertoli/metabolismo , Espermatocitos/metabolismo , Espermatogénesis/fisiología
10.
Science ; 247(4943): 704-7, 1990 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-2154035

RESUMEN

Nerve growth factor (NGF) is synthesized in male germ cells. The NGF receptor (NGFR) mRNA was found in the Sertoli cells of rat testis. Hypophysectomy increased both NGFR mRNA in testis and the number of NGFR hybridizing cells in seminiferous tubules. This was suppressed by treatment with chorionic gonadotropin or testosterone, but not with follicle-stimulating hormone. The NGFR mRNA also increased after destruction of Leydig cells or blocking of the androgen receptor. This suggests that NGF produced by male germ cells regulates testicular function in an androgen-modulated fashion by mediating an interaction germ and Sertoli cells.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , ARN Mensajero/genética , Receptores de Superficie Celular/genética , Células de Sertoli/metabolismo , Testosterona/farmacología , Animales , Gonadotropina Coriónica/farmacología , Sondas de ADN , Hormona Folículo Estimulante/farmacología , Hipofisectomía , Células Intersticiales del Testículo/efectos de los fármacos , Células Intersticiales del Testículo/fisiología , Masculino , Mesilatos/farmacología , Hibridación de Ácido Nucleico , Ratas , Ratas Endogámicas , Receptores Androgénicos/fisiología , Receptores de Factor de Crecimiento Nervioso , Testículo/metabolismo
12.
Steroids ; 149: 108417, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31150682

RESUMEN

Steroidogenic potential of the human fetal kidney (hFK) at the end of first trimester is poorly investigated. Little is known about the ontogeny of steroidogenic enzymes and activities of steroidogenic pathways in the hFK at early pregnancy. Our aim was to explore steroidogenesis and the expression of steroidogenic enzymes in the hFK at gestational weeks (GW) 9-12. Steroids in the hFK were analyzed by gas chromatography/coupled to tandem mass spectrometry. The expression of steroidogenic enzymes in the hFK at GW 9-12 was investigated by qPCR, automated Western blotting and immunohistochemistry. We observed that the hFK produced substantial amount of steroids of the Δ5 and Δ4 pathways and several steroid precursors in the biosynthesis of DHT via the backdoor pathway but not DHT itself. The levels of steroids and expression of relevant steroidogenic enzymes (e.g., CYP17A1, HSD3B1, HSD3B2, CYP11B1 and AKR1C4) we significantly higher in the hFK at GW11-12 compared to GW9. We also found the expression of sex steroid receptors (e.g., AR, ERα and ERß) in the hFK at GW9-12. No sex-dependent differences in the levels of all identified steroids and expression of steroidogenic enzymes in the hFK from male and female fetuses were found. Altogether, our data indicate that the hFK at early pregnancy is steroidogenic organ with potential to synthesize multiple steroids that may play an important role in the formation and development of this organ in humans.


Asunto(s)
Feto/metabolismo , Edad Gestacional , Riñón/embriología , Riñón/metabolismo , Esteroides/biosíntesis , Femenino , Regulación Enzimológica de la Expresión Génica , Humanos , Embarazo
13.
Steroids ; 141: 96-103, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30529237

RESUMEN

The onset of steroidogenesis in human fetal testes (HFT) during the first trimester is poorly investigated. One important unresolved question is the ontogeny of steroidogenic enzymes and formation of steroidogenic pathways in the HFT at early pregnancy. Our aim was to explore steroidogenesis, the expression of steroidogenic enzymes and their maturation in the HFT at gestational weeks (GW) 8-12. Steroids in the HFT were analyzed by gas chromatography/coupled to tandem mass spectrometry. The expression of steroidogenic enzymes in the HFT at GW8-12 was investigated by qPCR, automated Western blotting and immunohistochemistry. We demonstrated that the HFT at GW8-9 produced low level of testosterone via the Δ4 pathway and progesterone was the major steroid found in the testicular tissue. In contrast, more mature Leydig cells from the HFT at GW11-12 synthesized high levels of androgens via the Δ5 pathway. We also observed a significant upregulation of the expression of StAR, CYP11A1, CYP17A1 and its accessory proteins, P450 oxidoreductase (POR) and cytochrome b5 in the HFT at GW11-12 compared to GW8-9. Altogether, our data suggest that that human fetal Leydig cells differentiate rapidly at the end of the first trimester by acquiring capacity to express high levels of steroidogenic enzymes and switch from the Δ4 to the Δ5 pathways to synthesize high levels of androgens due to maturation of the CYP17-POR-b5 complex.


Asunto(s)
Edad Gestacional , Esteroides/biosíntesis , Testículo/metabolismo , Cromatografía de Gases , Humanos , Masculino , Esteroide 17-alfa-Hidroxilasa/genética , Esteroide 17-alfa-Hidroxilasa/metabolismo , Esteroides/análisis , Espectrometría de Masas en Tándem
14.
Mol Cell Endocrinol ; 477: 148-155, 2018 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-29928928

RESUMEN

It is generally accepted that androgens produced by fetal Leydig cells (FLC) control proper masculinization of the male external genitalia. Here, we hypothesized that the human genital tubercle (GT) has potential to synthesize androgens independently of FLC at early pregnancy. We observed that human GT of both genders have capacity to synthesize steroids of the Δ4, Δ5 and alternative pathway of DHT synthesis including the androgen itself. The presence of steroids in the GT was associated with the expression of corresponding steroidogenic enzymes. Levels of steroids and the expression of steroidogenic enzymes were similar in the GT from male and female fetuses. In contrast to the GT, the human fetal testis synthesized DHT from testosterone but not via the alternative pathway. Our findings strongly suggest that the human GT at early pregnancy can synthesize DHT via the alternative pathway, which may play an important role in organogenesis of the urethra.


Asunto(s)
Genitales Masculinos/anatomía & histología , Esteroides/metabolismo , Femenino , Feto/metabolismo , Edad Gestacional , Humanos , Masculino , Embarazo , Primer Trimestre del Embarazo/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Caracteres Sexuales , Testículo/metabolismo
15.
J Endocrinol ; 194(3): 603-9, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17761899

RESUMEN

Phthalate esters are known to exert harmful effects on mammalian reproduction and fertility, but their potential adverse effects on the hormonal functions of the ovary have not yet been elucidated in detail. Here, we investigated the effects of di-(2-ethylhexyl) phthalate (DEHP) on the hypothalamic-pituitary-gonadal axis of young developing female rats, as well as on ex vivo steroidogenesis by granulosa cells (GCs) and secretion of LH by gonadotropes. Exposure of 20-day-old female rats to 500 mg DEHP by oral gavage once daily for 10 days reduced their serum levels of progesterone and estradiol, while tending to enhance levels of LH. Furthermore, primary cultures of GCs isolated from these rats exhibited an attenuated capacity to produce progesterone in response to stimulation by LH and FSH, as well as a lower degree of transport of endogenous cholesterol into mitochondria. Moreover, the ability of primary cultures of pituitary cells isolated from DEHP-treated rats to produce and secrete LH in response to GnRH was significantly enhanced. In addition, 2-ethylhexanoic acid, a metabolite of DEHP, significantly potentiated GnRH-stimulated production of LH by cultures of pituitary cells isolated from untreated 20-day-old female rats. Together, these data indicate that DEHP exerts dual effects on the pituitary-gonadal axis, stimulating the hormonal function of the pituitary and, at the same time, by inhibiting steroidogenesis by GCs.


Asunto(s)
Dietilhexil Ftalato/toxicidad , Células de la Granulosa/metabolismo , Plastificantes/toxicidad , Progesterona/biosíntesis , 3-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Aminoglutetimida/farmacología , Animales , Transporte Biológico , Caproatos/farmacología , Células Cultivadas , Colesterol/metabolismo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/antagonistas & inhibidores , Dihidrotestosterona/análogos & derivados , Dihidrotestosterona/farmacología , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/farmacología , Hormona Liberadora de Gonadotropina/farmacología , Células de la Granulosa/efectos de los fármacos , Hipotálamo/efectos de los fármacos , Hormona Luteinizante/biosíntesis , Hormona Luteinizante/sangre , Hormona Luteinizante/farmacología , Mitocondrias/metabolismo , Ovario/efectos de los fármacos , Hipófisis/efectos de los fármacos , Progesterona/sangre , Ratas , Ratas Sprague-Dawley , Maduración Sexual , Estimulación Química
16.
Mol Cell Biol ; 10(9): 4701-11, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1697032

RESUMEN

The gene encoding glutamic acid decarboxylase (GAD), the key enzyme in the synthesis of the inhibitory neurotransmitter gamma-aminobutyric acid, is shown to be expressed in the testis of several different species. Nucleotide sequence analysis of a cDNA clone isolated from the human testis confirmed the presence of GAD mRNA in the testis. The major GAD mRNA in the testis was 2.5 kilobases. Smaller amounts of a 3.7-kilobase mRNA with the same size as GAD mRNA in the brain was also detected in the testis. In situ hybridization using a GAD-specific probe revealed GAD mRNA expressing spermatocytes and spermatids located in the middle part of rat seminiferous tubules. Studies on the ontogeny of GAD mRNA expression showed low levels of GAD mRNA in testes of prepubertal rats, with increasing levels as sexual maturation is reached, compatible with GAD mRNA expression in germ cells. In agreement with this, fractionation of cells from the rat seminiferous epithelium followed by Northern (RNA) blot analysis showed the highest levels of GAD mRNA associated with spermatocytes and spermatids. Evidence for the presence of GAD protein in the rat testis was obtained from the demonstration of GAD-like immunoreactivity in seminiferous tubules, predominantly at a position where spermatids and spermatozoa are found. Furthermore, GAD-like immunoreactivity was seen in the midpiece of ejaculated human spermatozoa, the part that is responsible for generating energy for spermatozoan motility.


Asunto(s)
Expresión Génica , Glutamato Descarboxilasa/genética , Neurotransmisores/biosíntesis , Testículo/enzimología , Animales , Secuencia de Bases , Bovinos , Clonación Molecular , ADN/genética , ADN/aislamiento & purificación , Humanos , Técnicas In Vitro , Células Intersticiales del Testículo/enzimología , Masculino , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , ARN/genética , ARN/aislamiento & purificación , ARN Mensajero/genética , ARN Mensajero/aislamiento & purificación , Ratas , Ratas Endogámicas , Túbulos Seminíferos/enzimología , Homología de Secuencia de Ácido Nucleico , Espermatozoides/enzimología , Transcripción Genética
17.
Endocr Connect ; 6(6): 348-359, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28592511

RESUMEN

The onset of steroidogenesis in human fetal adrenal glands (HFA) during the first trimester is poorly investigated. An unresolved question is the capacity of the HFA to produce potent androgen DHT via conventional and/or the backdoor pathway(s) at the end of first trimester, when androgen-responsive organs are developed. Our aim was to explore steroidogenesis and the expression of steroidogenic enzymes and transcription factors in HFA at gestational weeks (GW) 9-12 with focus on their androgenic potential. Steroids in the HFA were analyzed by gas chromatography/mass spectrometry. The expression of steroidogenic enzymes and transcription factors in the HFA at GW9-12 was investigated by qPCR, automated Western blotting and immunohistochemistry. We demonstrated that during GW9-12 HFA produced steroids of the ∆5, ∆4 and the backdoor pathways of the biosynthesis of DHT, though the latter was limited to production of 17α-OH-dihydroprogesterone, androsterone and androstanedione without further conversion to DHT. The only androgens identified in the HFA were testosterone and androsterone, a precursor in the biosynthesis of DHT. We also observed higher levels of CYP17A1 but low expression of 3ßHSD2 at GW11-12 in the HFA. Elevated levels of CYP17A1 were associated with an increased expression of SF-1 and GATA-6. Altogether, our data demonstrate that of those steroids analyzed, the only potent androgen directly produced by the HFA at GW9-12 was testosterone. The onset of steroidogenesis in the HFA is a complex process that is regulated by the coordinated action of related transcription factors.

18.
Bone Marrow Transplant ; 52(4): 600-605, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28067869

RESUMEN

The aim of this study was to analyze the prevalence of frailty and physical health limitations among long-term survivors of high-risk neuroblastoma (HR NBL) and to investigate whether frail health is associated with variables of cardiovascular function, markers of inflammation and telomere length. A national study cohort of 19 (median age 22, range 16-30 years) long-term (>10 years) HR NBL survivors was studied and the findings were compared with 20 age- and sex-matched controls. Frailty was defined as ⩾3 of the following conditions: low muscle mass, low energy expenditure, slow running and weakness. The prevalence of frailty was significantly higher among the HR NBL survivors 9/19 (47%) than among the controls (0%). Thirteen (68%) of the survivors reported significant physical health limitations in vigorous activities, as opposed to none of the controls. The HR NBL survivors had significantly shorter telomere length and higher serum levels of high sensitivity C-reactive protein than did the controls. Frail health and poor physical functioning are prevalent among HR NBL survivors and suggest premature aging. Survivors with gonadal damage, very low fat mass percentage, low glycosylated hemoglobin A1c and increased common carotid artery intima-media thickness may be more prone to early aging after high dose therapy.


Asunto(s)
Envejecimiento Prematuro/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Neuroblastoma/complicaciones , Sobrevivientes , Adolescente , Adulto , Biomarcadores/análisis , Proteína C-Reactiva/análisis , Grosor Intima-Media Carotídeo , Estudios de Cohortes , Femenino , Fragilidad/diagnóstico , Humanos , Masculino , Neuroblastoma/fisiopatología , Neuroblastoma/terapia , Prevalencia , Telómero/ultraestructura , Trasplante Autólogo , Adulto Joven
19.
J Mol Endocrinol ; 36(2): 327-36, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16595703

RESUMEN

Interleukin-1alpha (IL-1alpha) plays an important role in the regulation of immune responses as well as in non-inflammatory events in different types of cells. Here we have investigated the involvement of the extracellular signal-regulated kinase (ERK) cascade in IL-1alpha-induced steroidogenesis by primary cultures of immature rat Leydig cells. Our findings indicate that protein kinase C functions as an upstream component of signal transduction from the IL-1 receptor type I (IL-1RI) to the ERK cascade. It was observed that IL-1alpha upregulated both steroidogenic acute regulatory (StAR) protein expression and its phosphorylation when compared with controls. Selective inhibition of these mitogen-activated protein kinases (MAPKs) by UO126 enhanced both the expression and phosphorylation of the StAR protein, but suppressed androgen production by the immature Leydig cells as well as dissipating the mitochondrial electrochemical potential (Psim) in these cells. The evidence that water-soluble cholesterol but not 22R-hydroxycholesterol-stimulated steroidogenesis was inhibited by UO126 suggested that an intact Psim across the inner mitochondrial membrane is required for cholesterol translocation and is positively regulated by the ERK cascade. We propose that activation of ERKs by IL-1alpha plays a dual role in the regulation of steroidogenesis in immature Leydig cells: these MAPKs downregulate StAR expression and phosphorylation, while at the same time they support an intact Psim across the inner mitochondrial membrane, thereby promoting translocation of cholesterol into the mitochondria of the Leydig cell.


Asunto(s)
Diferenciación Celular , Interleucina-1/farmacología , Células Intersticiales del Testículo/citología , Células Intersticiales del Testículo/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Esteroides/biosíntesis , Animales , Transporte Biológico , Butadienos/farmacología , Células Cultivadas , Colesterol/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Activación Enzimática/efectos de los fármacos , Células Intersticiales del Testículo/enzimología , Células Intersticiales del Testículo/metabolismo , Masculino , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Nitrilos/farmacología , Fosforilación/efectos de los fármacos , Proteína Quinasa C/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
20.
Cancer Res ; 61(2): 706-10, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11212272

RESUMEN

A rat T-cell leukemia model was used to study the safety of germ cell transplantation as a mean of preventing infertility in males undergoing gonadotoxic cancer treatment. Donor germ cells were harvested from the testes of terminally ill leukemic rats and were either used directly or cryopreserved and thawed before transplantation by rete testis microinjection. All rats transplanted with testicular cells from leukemic donors developed signs of terminal rat T-cell leukemia, whereas control animals remained healthy. Cryopreservation of the donor germ cells caused a 3- to 6-day delay in the terminal phase of leukemia. When a known number of leukemic cells were mixed with germ cells and microinjected into the testis, the rate of appearance of terminal leukemia was directly related to the number of transferred leukemic lymphoblasts. As few as 20 leukemic cells were able to cause a cancer relapse resulting in terminal leukemia 21 days after transplantation in three of five transplanted animals. Our results demonstrate that germ cell transplantation with the presently used techniques is not safe enough for clinical use. Improved methods for purging testicular specimens of cancer cells or totally new approaches with transient xenogenetic host models to detect contamination of malignant cells must be developed before this technique can be offered to patients without fear of disease relapse.


Asunto(s)
Trasplante de Células , Leucemia de Células T/patología , Testículo/trasplante , Animales , Trasplante de Células/efectos adversos , Criopreservación , Leucemia de Células T/etiología , Leucemia de Células T/mortalidad , Masculino , Ratas , Espermatogonias/citología , Espermatogonias/trasplante , Espermatozoides/citología , Espermatozoides/trasplante , Tasa de Supervivencia , Testículo/citología
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