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1.
Andrology ; 7(6): 778-793, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31099174

RESUMO

BACKGROUND: Gynecomastia (GM) is a benign proliferation of the glandular tissue of the breast in men. It is a frequent condition with a reported prevalence of 32-65%, depending on the age and the criteria used for definition. GM of infancy and puberty are common, benign conditions resolving spontaneously in the majority of cases. GM of adulthood is more prevalent among the elderly and proper investigation may reveal an underlying pathology in 45-50% of cases. OBJECTIVES: The aim was to provide clinical practice guidelines for the evaluation and management of GM. MATERIALS AND METHODS: A literature search of articles in English for the term 'gynecomastia' was conducted. Evidence-based recommendations were developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. RESULTS: A set of five statements and fifteen clinical recommendations was formulated. CONCLUSIONS: The purpose of GM assessment should be the detection of underlying pathological conditions, reversible causes (administration/abuse of aggravating substances), and the discrimination from other breast lumps, particularly breast cancer. Assessment should comprise a thorough medical history and physical examination of the breast and genitalia (including testicular ultrasound). A set of laboratory investigations may integrate the evaluation: testosterone (T), estradiol (E2), sex hormone-binding globulin (SHBG), luteinizing hormone (LH), follicular stimulating hormone (FSH), thyroid stimulating hormone (TSH), prolactin, human chorionic gonadotropin (hCG), alpha-fetal protein (AFP), liver and renal function tests. Breast imaging may be used whenever the clinical examination is equivocal. In suspicious lesions, core needle biopsy should be sought directly instead. Watchful waiting is recommended after treatment of underlying pathology or discontinuation of substances associated with GM. T treatment should be offered to men with proven T deficiency. The use of selective estrogen receptor modulators (SERMs), aromatase inhibitors (AIs) and non-aromatizable androgens is not justified in general. Surgical treatment is the therapy of choice for patients with long-lasting GM. SUMMARY OF STATEMENTS (S) AND RECOMMENDATIONS (R): S1. Gynecomastia (GM) is a benign proliferation of glandular tissue of the breast in males. S2. GM of infancy is a common condition that usually resolves spontaneously, typically within the first year of life. S3. GM of puberty is a common condition, affecting approximately 50% of mid-pubertal boys; in more than 90% of cases, it resolves spontaneously within 24 months. S4. The prevalence of GM in adulthood increases with increasing age; proper investigation may reveal an underlying pathology in approximately 45-50% of the cases. S5. Male breast cancer is rare; GM should not be considered a premalignant condition. The following recommendations are divided into 'strong', denoted by the number 1 and associated with the terminology 'we recommend', and 'weak' denoted by the number 2 and associated with the phrase 'we suggest'. The grading of the quality of evidence is denoted as follows: ⊕○○○ for very low-quality evidence; ⊕⊕○○ for low quality; ⊕⊕⊕○ for moderate quality; and ⊕⊕⊕⊕ for high quality. R1. The presence of an underlying pathology should be considered in GM of adulthood. We recommend that the identification of an apparent reason for GM in adulthood, including the use of medication known to be associated with GM, should not preclude a detailed investigation (1 ⊕⊕⊕○). R2. We suggest that the initial screening to rule out lipomastia, obvious breast cancer, or testicular cancer might be performed by a general practitioner or another non-specialist (2 ⊕○○○). R3. We recommend that in those cases where a thorough diagnostic workup is warranted, it should be performed by a specialist (1 ⊕○○○). R4. We recommend that the medical history should include information on the onset and duration of GM, sexual development and function, and administration or abuse of substances associated with GM (1 ⊕⊕⊕○). R5. We recommend that the physical examination should detect signs of under-virilization or systemic disease (1 ⊕⊕⊕⊕). R6. We recommend that breast examination should confirm the presence of palpable glandular tissue to discriminate GM from lipomastia (pseudo-gynecomastia) and rule out the suspicion of malignant breast tumor (1 ⊕⊕⊕⊕). R7. We recommend that the physical examination should include the examination of the genitalia to rule out the presence of a palpable testicular tumor and to detect testicular atrophy (1 ⊕⊕⊕⊕). R8. We recommend that genitalia examination is aided by a testicular ultrasound, as the detection of a testicular tumor by palpation has low sensitivity (1 ⊕⊕○○). R9. We suggest that a set of evaluations may include T, E2 , SHBG, LH, FSH, TSH, prolactin, hCG, AFP, and liver and renal function tests (2 ⊕⊕○○). R10. We suggest that breast imaging may offer assistance, where the clinical examination is equivocal (2 ⊕⊕○○). R11. We suggest that, if the clinical picture is suspicious for a malignant lesion, core needle biopsy should be performed (2 ⊕⊕○○). R12. We recommend watchful waiting after treatment of underlying pathology or discontinuation of the administration/abuse of substances associated with GM (1 ⊕⊕○○). R13. We recommend that T treatment should be offered only to men with proven testosterone deficiency (1 ⊕⊕⊕○). R14. We do not recommend the use of selective estrogen receptor modulators (SERMs), aromatase inhibitors (AIs), or non-aromatizable androgens in the treatment of GM in general (1 ⊕⊕○○). R15. We suggest surgical treatment only for patients with long-lasting GM, which does not regress spontaneously or following medical therapy. The extent and type of surgery depend on the size of breast enlargement, and the amount of adipose tissue (2 ⊕⊕○○).


Assuntos
Mama/fisiopatologia , Ginecomastia/diagnóstico , Ginecomastia/terapia , Testosterona/uso terapêutico , Adolescente , Adulto , Androgênios/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Mama/diagnóstico por imagem , Neoplasias da Mama Masculina/diagnóstico , Ginecomastia/fisiopatologia , Humanos , Lactente , Recém-Nascido , Lipoma/diagnóstico , Masculino , Guias de Prática Clínica como Assunto , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Neoplasias Testiculares/diagnóstico , Testosterona/deficiência
2.
Sci Rep ; 6: 29324, 2016 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-27381834

RESUMO

A straightforward solution-based method to modify the biofunctionality of stainless steel (SS) using heterobifunctional silane-polyethylene glycol (silane-PEG) overlayers is reported. Reduced nonspecific biofouling of both proteins and bacteria onto SS and further selective biofunctionalization of the modified surface were achieved. According to photoelectron spectroscopy analyses, the silane-PEGs formed less than 10 Å thick overlayers with close to 90% surface coverage and reproducible chemical compositions. Consequently, the surfaces also became more hydrophilic, and the observed non-specific biofouling of proteins was reduced by approximately 70%. In addition, the attachment of E. coli was reduced by more than 65%. Moreover, the potential of the overlayer to be further modified was demonstrated by successfully coupling biotinylated alkaline phosphatase (bAP) to a silane-PEG-biotin overlayer via avidin-biotin bridges. The activity of the immobilized enzyme was shown to be well preserved without compromising the achieved antifouling properties. Overall, the simple solution-based approach enables the tailoring of SS to enhance its activity for biomedical and biotechnological applications.


Assuntos
Avidina/metabolismo , Incrustação Biológica/prevenção & controle , Biotina/metabolismo , Polietilenoglicóis/metabolismo , Silanos/metabolismo , Aço Inoxidável/química , Propriedades de Superfície , Aderência Bacteriana , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica
3.
Endocr Rev ; 36(6): E1-E150, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26544531

RESUMO

The Endocrine Society's first Scientific Statement in 2009 provided a wake-up call to the scientific community about how environmental endocrine-disrupting chemicals (EDCs) affect health and disease. Five years later, a substantially larger body of literature has solidified our understanding of plausible mechanisms underlying EDC actions and how exposures in animals and humans-especially during development-may lay the foundations for disease later in life. At this point in history, we have much stronger knowledge about how EDCs alter gene-environment interactions via physiological, cellular, molecular, and epigenetic changes, thereby producing effects in exposed individuals as well as their descendants. Causal links between exposure and manifestation of disease are substantiated by experimental animal models and are consistent with correlative epidemiological data in humans. There are several caveats because differences in how experimental animal work is conducted can lead to difficulties in drawing broad conclusions, and we must continue to be cautious about inferring causality in humans. In this second Scientific Statement, we reviewed the literature on a subset of topics for which the translational evidence is strongest: 1) obesity and diabetes; 2) female reproduction; 3) male reproduction; 4) hormone-sensitive cancers in females; 5) prostate; 6) thyroid; and 7) neurodevelopment and neuroendocrine systems. Our inclusion criteria for studies were those conducted predominantly in the past 5 years deemed to be of high quality based on appropriate negative and positive control groups or populations, adequate sample size and experimental design, and mammalian animal studies with exposure levels in a range that was relevant to humans. We also focused on studies using the developmental origins of health and disease model. No report was excluded based on a positive or negative effect of the EDC exposure. The bulk of the results across the board strengthen the evidence for endocrine health-related actions of EDCs. Based on this much more complete understanding of the endocrine principles by which EDCs act, including nonmonotonic dose-responses, low-dose effects, and developmental vulnerability, these findings can be much better translated to human health. Armed with this information, researchers, physicians, and other healthcare providers can guide regulators and policymakers as they make responsible decisions.


Assuntos
Disruptores Endócrinos/toxicidade , Animais , Compostos Benzidrílicos , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/induzido quimicamente , Diabetes Mellitus/epidemiologia , Endocrinologia , Exposição Ambiental , Feminino , Herbicidas , Humanos , Masculino , Neoplasias Hormônio-Dependentes/epidemiologia , Transtornos do Neurodesenvolvimento/induzido quimicamente , Transtornos do Neurodesenvolvimento/epidemiologia , Sistemas Neurossecretores/efeitos dos fármacos , Obesidade/induzido quimicamente , Obesidade/epidemiologia , Praguicidas , Fenóis , Ácidos Ftálicos/toxicidade , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/epidemiologia , Reprodução/efeitos dos fármacos , Sociedades Médicas , Glândula Tireoide/efeitos dos fármacos
4.
Endocr Rev ; 36(6): 593-602, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26414233

RESUMO

This Executive Summary to the Endocrine Society's second Scientific Statement on environmental endocrine-disrupting chemicals (EDCs) provides a synthesis of the key points of the complete statement. The full Scientific Statement represents a comprehensive review of the literature on seven topics for which there is strong mechanistic, experimental, animal, and epidemiological evidence for endocrine disruption, namely: obesity and diabetes, female reproduction, male reproduction, hormone-sensitive cancers in females, prostate cancer, thyroid, and neurodevelopment and neuroendocrine systems. EDCs such as bisphenol A, phthalates, pesticides, persistent organic pollutants such as polychlorinated biphenyls, polybrominated diethyl ethers, and dioxins were emphasized because these chemicals had the greatest depth and breadth of available information. The Statement also included thorough coverage of studies of developmental exposures to EDCs, especially in the fetus and infant, because these are critical life stages during which perturbations of hormones can increase the probability of a disease or dysfunction later in life. A conclusion of the Statement is that publications over the past 5 years have led to a much fuller understanding of the endocrine principles by which EDCs act, including nonmonotonic dose-responses, low-dose effects, and developmental vulnerability. These findings will prove useful to researchers, physicians, and other healthcare providers in translating the science of endocrine disruption to improved public health.


Assuntos
Disruptores Endócrinos/toxicidade , Animais , Compostos Benzidrílicos/toxicidade , Diabetes Mellitus/induzido quimicamente , Diabetes Mellitus/epidemiologia , Endocrinologia , Exposição Ambiental , Epigênese Genética , Feminino , Interação Gene-Ambiente , Herbicidas/toxicidade , Humanos , Masculino , Neoplasias Hormônio-Dependentes/induzido quimicamente , Neoplasias Hormônio-Dependentes/epidemiologia , Transtornos do Neurodesenvolvimento/induzido quimicamente , Transtornos do Neurodesenvolvimento/epidemiologia , Sistemas Neurossecretores/efeitos dos fármacos , Obesidade/induzido quimicamente , Obesidade/epidemiologia , Praguicidas/toxicidade , Fenóis/toxicidade , Ácidos Ftálicos/toxicidade , Bifenilos Policlorados/toxicidade , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/epidemiologia , Reprodução/efeitos dos fármacos , Sociedades Médicas , Glândula Tireoide/efeitos dos fármacos
5.
Andrology ; 3(5): 1000-14, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26311345

RESUMO

Cell cycle control during spermatogenesis is a highly complex process owing to the control of the mitotic expansion of the spermatogonial cell population and following meiosis, induction of DNA breaks during meiosis and the high levels of physiological germ-cell apoptosis. We set out to study how E2F1, a key controller of cell cycle, apoptosis, and DNA damage responses, functions in the developing and adult testis. We first analyzed the expression pattern of E2f1 during post-natal testis development using RNA in situ hybridization, which showed a differential expression pattern of E2f1 in the adult and juvenile mouse testes. To study the function of E2f1, we took advantage of the E2F1(-/-) mouse line, which was back-crossed to C57Bl/6J genetic background. E2f1 loss led to a severe progressive testicular atrophy beginning at the age of 20 days. Spermatogonial apoptosis during the first wave of spermatogenesis was decreased. However, already in the first wave of spermatogenesis an extensive apoptosis of spermatocytes was observed. In the adult E2F1(-/-) testes, the atrophy due to loss of spermatocytes was further exacerbated by loss of spermatogonial stem cells. Surprisingly, only subtle changes in global gene expression array profiling were observed in E2F1(-/-) testis at PND20. To dissect the changes in each testicular cell type, an additional comparative analysis of the array data was performed making use of previously published data on transcriptomes of the individual testicular cell types. Taken together, our data indicate that E2F1 has a differential role during first wave of spermatogenesis and in the adult testis, which emphasizes the complex nature of cell cycle control in the developing testis.


Assuntos
Apoptose/genética , Fator de Transcrição E2F1/genética , Espermatócitos/metabolismo , Espermatogênese/genética , Células-Tronco/citologia , Animais , Atrofia/genética , Atrofia/patologia , Ciclo Celular/genética , Quebras de DNA , Reparo do DNA , Fator de Transcrição E2F1/metabolismo , Hormônio Foliculoestimulante/sangue , Perfilação da Expressão Gênica , Hibridização In Situ , Hormônio Luteinizante/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/biossíntese , Espermatogônias/metabolismo , Testículo/patologia , Transcrição Gênica/genética
6.
Cell Death Dis ; 5: e1274, 2014 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-24901045

RESUMO

The retinoblastoma protein (RB) is essential for normal cell cycle control. RB function depends, at least in part, on interactions with the E2F family of DNA-binding transcription factors (E2Fs). To study the role of RB in the adult testis, a Sertoli cell (SC)-specific Rb knockout mouse line (SC-RbKO) was generated using the Cre/loxP recombination system. SC-RbKO mice exhibited an age-dependent testicular atrophy, impaired fertility, severe SC dysfunction, and spermatogenic defects. Removal of Rb in SC induced aberrant SC cycling, dedifferentiation, and apoptosis. Here we show that E2F3 is the only E2F expressed in mouse SCs and that RB interacts with E2F3 during mouse testicular development. In the absence of RB, the other retinoblastoma family members p107 and p130 began interacting with E2F3 in the adult testes. In vivo silencing of E2F3 partially restored the SC maturation and survival as well as spermatogenesis in the SC-RbKO mice. These results point to RB as a key regulator of SC function in adult mice and that the RB/E2F3 pathway directs SC maturation, cell cycle quiescence, and RB protects SC from apoptosis.


Assuntos
Diferenciação Celular/fisiologia , Fator de Transcrição E2F3/metabolismo , Proteína do Retinoblastoma/metabolismo , Células de Sertoli/metabolismo , Animais , Apoptose/genética , Fator de Transcrição E2F3/genética , Inativação Gênica , Masculino , Camundongos , Camundongos Knockout , Proteína do Retinoblastoma/genética , Células de Sertoli/citologia
7.
Eur J Endocrinol ; 168(2): 227-33, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23161753

RESUMO

OBJECTIVE: To investigate whether a population-level decline in serum testosterone exists in Finnish men. In comparison with other European populations, Finnish men have compared well in the studies of reproductive health (i.e. semen quality, incidence of cryptorchidism and testicular cancer); thus, we expected no significant cohort-dependent decrease in serum testosterone. METHODS: We analysed serum levels of testosterone, gonadotrophin and sex hormone binding globulin (SHBG) in 3271 men representing different ages (25-74 years) and birth cohorts within three large Finnish population surveys conducted in 1972, 1977 and 2002. RESULTS: Serum testosterone levels decreased (from 25.3 nmol/l in 25- to 29-year-old men gradually to 16.9 nmol/l in 70- to 74-year-old men), whereas SHBG and gonadotrophin levels increased with increasing age. In addition, a significant secular trend in testosterone (total and free), SHBG and gonadotrophin levels was observed with lower levels in more recently born age-matched men. Serum testosterone level decreased in men aged 60-69 years from 21.9 nmol/l (men born 1913-1922) to 13.8 nmol/l (men born 1942-1951). These decreases remained significant following adjustment for BMI. An age-independent birth cohort effect existed on reproductive hormones measured in the Finnish men. In concert with the lower free testosterone levels, we observed lower gonadotrophin levels, suggesting that while there may be detrimental changes at the gonad level, the hypothalamus-pituitary-axis is not responding appropriately to this change. CONCLUSIONS: The more recently born Finnish men have lower testosterone levels than their earlier born peers. This study offers no explanation for this substantial recent adverse development.


Assuntos
Testosterona/sangue , Adulto , Fatores Etários , Idoso , Efeito de Coortes , Estudos de Coortes , Finlândia , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/metabolismo , População Branca
8.
J Clin Endocrinol Metab ; 97(12): 4588-95, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23015652

RESUMO

CONTEXT: A randomized controlled study was conducted comparing the outcome of surgery for congenital cryptorchidism at 9 months or 3 yr of age. OBJECTIVE: The aim of the study was to investigate whether surgery at 9 months is more beneficial than at 3 yr and to identify early endocrine markers of importance for testicular development. PATIENTS AND METHODS: A total of 213 biopsies were taken at orchidopexy, and the number of germ and Sertoli cells per 100 seminiferous cord cross-sections and the surface area of seminiferous tubules and interstitial tissue were analyzed. Inhibin B, FSH, LH, and testosterone were determined. Testicular volume was assessed by ultrasonography and by a ruler. RESULTS: The number of germ and Sertoli cells and testicular volume at 9 months were significantly larger than at 3 yr. The intraabdominal testes showed the largest germ cell depletion at 3 yr. At both ages, testicular volume correlated to the number of germ and Sertoli cells. None of the hormones measured during the first 6 months of life (LH, FSH, testosterone, and inhibin B) could predict the number of germ or Sertoli cells at either 9 or 36 months of age, nor could hormone levels predict whether spontaneous descent would occur or not. CONCLUSION: Morphometric and volumetric data show that orchidopexy at 9 months is more beneficial for testicular development than an operation at 3 yr of age. Testicular volume was furthermore shown to reflect germ cell numbers in early childhood, whereas endocrine parameters could not predict cellular structure of the testis or its spontaneous descent.


Assuntos
Criptorquidismo/metabolismo , Criptorquidismo/patologia , Criptorquidismo/cirurgia , Hormônios/metabolismo , Orquidopexia , Testículo/fisiopatologia , Fatores Etários , Pré-Escolar , Criptorquidismo/fisiopatologia , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Hormônios/sangue , Humanos , Lactente , Recém-Nascido , Inibinas/sangue , Inibinas/metabolismo , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Masculino , Orquidopexia/métodos , Orquidopexia/reabilitação , Tamanho do Órgão , Espermatogênese/fisiologia , Testículo/metabolismo , Testículo/cirurgia , Testosterona/sangue , Testosterona/metabolismo
9.
Int J Androl ; 35(1): 1-10, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21332503

RESUMO

In North European countries, a significant difference in semen quality among young men has been shown. Men from the western countries, Denmark, Germany and Norway, have lower semen quality than men from the eastern countries Finland, Estonia and Lithuania. Similarly, men in the western countries have a higher risk of testicular cancer. According to the testicular dysgenesis syndrome (TDS) concept that suggests a link between risk of impaired semen quality and increased risk of testicular cancer, Spanish men would be expected to have a semen quality at a normal level because of their very low testis cancer risk. We therefore investigated 273 men from the Almeria region in the Southern Spain to test this hypothesis. The men delivered semen samples, underwent physical examinations, had a blood sample drawn and provided information on lifestyle and reproductive health parameters. The investigations took place from November 2001 to December 2002. Adjusting for effects of confounders, the median sperm concentration and total sperm count were 62 (95% confidence interval 47-82) million/mL and 206 (153-278) million, respectively. The median numbers of motile and morphologically normal spermatozoa assessed according to strict criteria were 59% (57-62%) and 9.4% (8.6-10.0%), respectively. The median total testosterone and calculated free androgen index were 28 nm (26-30) and 95 (88-103), respectively. Assuming that the investigated men, to a large extent, are representative of the population of young men the Southern Spain, the results show that these have normal semen quality and reproductive hormone levels as expected in a population with a low incidence of testicular cancer.


Assuntos
Hormônios/sangue , Sêmen , Humanos , Masculino , Espanha
10.
Sex Dev ; 5(4): 188-96, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21654158

RESUMO

Searching for useful markers of spermatogonial stem cells and their differentiation, we used rat testes from ages representing different stages of testicular maturation to investigate the expression profile of transcription factor activation protein-2γ (Ap-2γ). The immunohistochemical and immunocytochemical evaluation using Ap-2γ and promyelocytic leukemia zinc finger in combination with sorting of CD9 and CD90 positive cells (undifferentiated spermatogonia) by fluorescence-activated cell sorting was performed. Our experiments revealed that Ap-2γ is detectable in testes of late fetal age and up to 60 days postnatally and is expressed in gonocytes and spermatogonia from late fetal age throughout all maturational stages. Restricted nuclear expression of Ap-2γ to undifferentiated male germ cells was verified by coexpression of Ap-2γ with promyelocytic leukemia zinc finger in sections of paraffin-embedded testes as well as in cells sorted positive for CD9 and CD90 expression. Our study demonstrated clearly that nuclear expression of Ap-2γ is a useful marker for identifying undifferentiated male germ cells, although its functional role is yet to be fully explored.


Assuntos
Testículo/química , Testículo/crescimento & desenvolvimento , Fator de Transcrição AP-2/análise , Animais , Antígenos CD/análise , Biomarcadores/análise , Diferenciação Celular , Núcleo Celular/química , Citometria de Fluxo , Imuno-Histoquímica , Masculino , Glicoproteínas de Membrana/análise , Ratos , Ratos Sprague-Dawley , Espermatócitos/química , Espermatogônias/química , Testículo/embriologia , Tetraspanina 29 , Antígenos Thy-1/análise
11.
Int J Androl ; 34(4 Pt 2): e37-48, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21366607

RESUMO

Impaired semen quality and testicular cancer may be linked through a testicular dysgenesis syndrome of foetal origin. The incidence of testis cancer has been shown to increase among Finnish men, whereas there is no recent publication describing temporal trends in semen quality. Therefore, we carried out a prospective semen quality study and a registry study of testis cancer incidence among Finnish men to explore recent trends. A total of 858 men were investigated in the semen quality study during 1998-2006. Median sperm concentrations were 67 (95% CI 57-80) million/mL, 60 (51-71) and 48 (39-60) for birth cohorts 1979-81, 1982-83 and 1987; total sperm counts 227 (189-272) million, 202 (170-240) and 165 (132-207); total number of morphologically normal spermatozoa 18 (14-23) million, 15 (12-19) and 11 (8-15). Men aged 10-59 years at the time of diagnosis with testicular cancer during 1954-2008 were included in the registry study, which confirmed the increasing incidence of testicular cancer in recent cohorts. These simultaneous and rapidly occurring adverse trends suggest that the underlying causes are environmental and, as such, preventable. Our findings necessitate not only further surveillance of male reproductive health but also research to detect and remove the underlying factors.


Assuntos
Sêmen/citologia , Neoplasias Testiculares/epidemiologia , Adolescente , Adulto , Criança , Finlândia/epidemiologia , Disgenesia Gonadal/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/anormalidades , Espermatozoides/patologia
12.
J Mol Endocrinol ; 45(3): 147-59, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20554652

RESUMO

Spermatogenesis is a complex and coordinated process leading to the formation of spermatozoa. This event, which is under the control of numerous endocrine and paracrine factors, seems to also be controlled by estrogens which exert their effects via nuclear estrogen receptors (ESRs) ESR1 and ESR2. Estrogens are synthesized by aromatase which is biologically expressed in the rat testis. The objective of our study was to clarify the gene expression patterns of aromatase and ESRs according to age and in the two compartments of the adult rat testis. In the adult, transcripts of aromatase vary according to the germ cell type and to the stages of seminiferous epithelium, a maximum being observed at stage I. The ESR1 gene is highly expressed in the adult testis and in stages from VIIc-d to XIV. Moreover, both ESR mRNA levels are higher in purified round spermatids than in pachytene spermatocytes, suggesting a putative role of estrogens in the haploid steps of spermatogenesis. The variability of the results in the expression of both ESRs led us to explore the putative presence of variants in the rat testis. Concerning ESR1, we have shown the presence of the full-length form and of one isoform with exon 4 deleted. For ESR2, besides the wild type, three isoforms were observed: one with exon 3 deleted, another with an insertion of 54 nucleotides, and the last one with both modifications. Therefore, the stage-regulated expression of aromatase and ESR1 genes in the rat testis suggests a likely role of estrogens in spermatogenesis.


Assuntos
Envelhecimento/genética , Aromatase/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Receptores de Estrogênio/genética , Testículo/citologia , Testículo/enzimologia , Animais , Compartimento Celular , Evolução Molecular , Masculino , Especificidade de Órgãos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Células de Sertoli/citologia , Células de Sertoli/enzimologia
13.
Int J Androl ; 33(2): 270-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19780864

RESUMO

Recent reports have confirmed a worldwide increasing trend of testicular cancer incidence, and a conspicuously high prevalence of this disease and other male reproductive disorders, including cryptorchidism and hypospadias, in Denmark. In contrast, Finland, a similarly industrialized Nordic country, exhibits much lower incidences of these disorders. The reasons behind the observed trends are unexplained, but environmental endocrine disrupting chemicals (EDCs) that affect foetal testis development are probably involved. Levels of persistent chemicals in breast milk can be considered a proxy for exposure of the foetus to such agents. Therefore, we undertook a comprehensive ecological study of 121 EDCs, including the persistent compounds dioxins, polychlorinated biphenyls (PCBs), pesticides and flame retardants, and non-persistent phthalates, in 68 breast milk samples from Denmark and Finland to compare exposure of mothers to this environmental mixture of EDCs. Using sophisticated, bioinformatic tools in our analysis, we reveal, for the first time, distinct country-specific chemical signatures of EDCs with Danes having generally higher exposure than Finns to persistent bioaccumulative chemicals, whereas there was no country-specific pattern with regard to the non-persistent phthalates. Importantly, EDC levels, including some dioxins, PCBs and some pesticides (hexachlorobenzene and dieldrin) were significantly higher in Denmark than in Finland. As these classes of EDCs have been implicated in testicular cancer or in adversely affecting development of the foetal testis in humans and animals, our findings reinforce the view that environmental exposure to EDCs may explain some of the temporal and between-country differences in incidence of male reproductive disorders.


Assuntos
Dioxinas/análise , Disruptores Endócrinos/análise , Exposição Ambiental , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Exposição Materna , Leite Humano/química , Bifenilos Policlorados/análise , Dinamarca , Dieldrin/análise , Dioxinas/toxicidade , Poluentes Ambientais/toxicidade , Feminino , Finlândia , Retardadores de Chama/análise , Hexaclorobenzeno/análise , Humanos , Hidrocarbonetos Clorados/toxicidade , Masculino , Praguicidas/análise , Neoplasias Testiculares/induzido quimicamente , Testículo/efeitos dos fármacos , Testículo/embriologia
14.
Reprod Toxicol ; 28(1): 66-74, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19490997

RESUMO

Exposure to antiandrogens during the critical developmental window (i.e. sexual differentiation) can permanently demasculinize the male phenotype. Here we have investigated the effects of developmental exposure to di-isononylphthalate (DINP) (250 and 750 mg/kg) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE) (50 and 100mg/kg) on 19.5-day-old fetal Sprague-Dawley rat testicular and adrenal steroidogenesis. Maternal exposure to DINP or p,p'-DDE on embryonic days (EDs) 13.5-17.5 did not down-regulate the activity of steroidogenesis in ED 19.5 male rat fetus. Protein expression levels of testicular and adrenal StAR, P450scc, 3beta-HSD and androgen receptor (AR) did not show any changes. However, p,p'-DDE caused clear abnormalities in the ultrastructure of steroidogenic cells in ED 19.5 rat testis and adrenal. These structural alterations can disturb the development and function of fetal testis and adrenal that may become evident later in life.


Assuntos
Corticosteroides/biossíntese , Glândulas Suprarrenais/efeitos dos fármacos , Antagonistas de Androgênios/toxicidade , Diclorodifenil Dicloroetileno/análogos & derivados , Hormônios Esteroides Gonadais/biossíntese , Exposição Materna , Ácidos Ftálicos/toxicidade , Testículo/efeitos dos fármacos , 3-Hidroxiesteroide Desidrogenases/genética , Glândulas Suprarrenais/embriologia , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/ultraestrutura , Antagonistas de Androgênios/administração & dosagem , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Diclorodifenil Dicloroetileno/administração & dosagem , Diclorodifenil Dicloroetileno/toxicidade , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Idade Gestacional , Masculino , Fosfoproteínas/genética , Gravidez , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/genética , Testículo/embriologia , Testículo/metabolismo , Testículo/ultraestrutura
15.
Endocr Dev ; 14: 167-73, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19293583

RESUMO

Cryptorchidism is part of the testicular dysgenesis syndrome (TDS), which includes other male reproductive disorders such as hypospadias, testis cancer and reduced semen quality. These diseases appear to be linked by common pathogenic mechanisms, interfering with normal fetal testis development. Testis development and descent is dependent on androgens and thus on an intact hypothalamus-pituitary-gonadal axis. Although cryptorchidism occurs in rare syndromes and genetic disorders, in the majority of children the etiology remains open. Many maternal and fetal risk factors have been previously identified but recently, scientific focus has also been directed to environmental hormone disrupting chemicals and lifestyle, as the prevalence of testis cancer and cryptorchidism has increased and semen quality decreased over few decades in several countries. Some persistent environmental chemicals, e.g. polychlorinated pesticides and polybrominated flame retardants, were associated with testicular maldescent and testis cancer. In addition, prenatal exposure to phthalates was negatively correlated to testosterone levels and anogenital distance as a measure of androgen effect in infant boys. Alcohol consumption and maternal smoking during pregnancy also appeared to be a risk factor for cryptorchidism. Thus, current evidence suggests that the development of the male reproductive tract may be susceptible to adverse effects of environmental hormone disrupters.


Assuntos
Criptorquidismo/epidemiologia , Criptorquidismo/patologia , Meio Ambiente , Disgenesia Gonadal/epidemiologia , Disgenesia Gonadal/patologia , Humanos , Masculino , Prevalência , Fatores de Risco
16.
Int J Androl ; 32(5): 575-85, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18637154

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic and widely investigated dioxin congener. In utero and lactational exposure to TCDD results in developmental and reproductive defects that are the most sensitive endpoints for TCDD toxicity. TCDD has a potential to interfere with steroid metabolism, but the mechanisms by which this occurs are not well understood. In this study, we investigated the effects of TCDD on prenatal rat steroidogenesis. Pregnant Sprague-Dawley female rats were treated once with TCDD (0, 0.3 or 1 microg/kg) by gavage on embryonic day (ED) 11 and the expression levels of androgen (AR) and estrogen receptors (ER), steroidogenic enzymes (P450scc and 3beta-HSD) and four regulatory factors (StAR, SF-1, GATA-4 and Insl-3) involved in foetal Leydig cell and adrenal function were analysed on ED 19.5. Hormonal status of male foetuses was determined by measuring testicular testosterone (T) levels, plasma luteinizing hormone (LH) and corticosterone concentrations. In utero exposure to TCDD reduced intratesticular T of foetal males (significant at 0.3 microg/kg TCDD) and tended to reduce the protein expression of ERalpha and AR of foetal male rat testis. Foetal male rat plasma LH levels were significantly reduced at the dose of 1 microg/kg TCDD, while corticosterone levels tended to be increased possibly because of the TCDD-induced stress. Only minor alterations in steroidogenesis were observed in rat adrenal. mRNA expression of developmental regulatory factors was not influenced by foetal TCDD exposure, except for significantly reduced adrenal SF-1. The results demonstrate that maternal exposure to TCDD suppressed testicular steroidogenesis of 19.5-day-old foetal male Sprague-Dawley rat. The highest dose of TCDD (1 microg/kg) had also an effect on pituitary LH secretion. Our data implicate that TCDD has direct testicular and pituitary effects on foetal male rat but with different dose-responses. These changes can lead to impaired steroidogenesis and it may result in the maldevelopment of the testis and weaken masculinization.


Assuntos
Dibenzodioxinas Policloradas/toxicidade , Esteroides/biossíntese , Animais , Feminino , Masculino , Ratos , Ratos Sprague-Dawley
17.
Acta Paediatr ; 97(7): 935-42, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18430073

RESUMO

AIM: Twenty-five male patients were investigated to elucidate the correlation of semen parameters and other related parameters in the assessment of spermatogenesis after childhood cancer treatment. METHODS: Evaluation of given cancer treatment, anthropometric and testicular size measurements, semen analysis, and measurement of gonadotrophins, testosterone, sex hormone-binding globulin (SHBG), and inhibin B were performed according to a protocol. RESULTS: Median (range) sperm concentration (SC) was 35.5 (0-273)x10(6)/mL, and percentage of motile sperm 56 (0-86)%. Testicular size (r=0.73, p<0.001) and the level of inhibin B (r=0.66, p<0.001) correlated strongly to SC. SC correlated negatively to FSH (r=0.46, p=0.03). Only testicular size predicted SC significantly (p=0.03). Inhibin B showed highest area under ROC curve (0.83, 95%CI 0.67-0.99) in showing SC<20x10(6)/mL. Body mass index (BMI) did not correlate with SC, but negative correlation between BMI and SHBG was found (r=-0.41, p=0.04). CONCLUSION: Although semen analysis is a useful instrument for fertility assessment in men, it is often difficult to get these samples from childhood cancer survivors. Thus, indirect methods are needed in prediction of possible sperm count impairment in postpubertal adolescents after cancer treatment. When combined with the data on testicular size and follicle-stimulating hormone (FSH) level, inhibin B gives valuable addition to the estimations of spermatogenesis.


Assuntos
Fertilidade , Neoplasias/terapia , Espermatogênese , Adolescente , Adulto , Criança , Pré-Escolar , Hormônio Foliculoestimulante/sangue , Seguimentos , Humanos , Lactente , Inibinas/sangue , Masculino , Espermatogênese/efeitos dos fármacos , Espermatogênese/efeitos da radiação , Testículo/anatomia & histologia , Testículo/diagnóstico por imagem , Testosterona/sangue , Ultrassonografia
18.
Int J Androl ; 30(4): 198-204; discussion 204-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17705804

RESUMO

Recently a worldwide rise in the incidence of testicular germ cell cancer (TGCC) has been repeatedly reported. The changing disease pattern may signal that other testicular problems may also be increasing. We have reviewed recent research progress, in particular evidence gathered in the Nordic countries, which shows strong associations between testicular cancer, undescended testis, hypospadias, poor testicular development and function, and male infertility. These studies have led us to suggest the existence of a testicular dysgenesis syndrome (TDS), of which TGCC, undescended testis, hypospadias/disorders of sex differentiation and male fertility problems may be symptoms with varying penetration. In spite of their fetal origin, most of the TDS symptoms, including TGCC and poor semen quality, can only be diagnosed in adulthood. Data from a Danish-Finnish research collaboration strongly suggest that trends in TGCC rates of a population may be 'whistle blowers' of other reproductive health problems. As cancer registries are often of excellent quality - in contrast to registries for congenital abnormalities - health authorities should consider an increase in TGCC as a warning that other reproductive health problems may also be rising.


Assuntos
Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Testiculares/terapia , Cromossomos Humanos X , Cromossomos Humanos Y , Desenvolvimento Fetal , Saúde Global , Humanos , Infertilidade Masculina/etiologia , Cariotipagem , Masculino , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Testiculares/embriologia , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/genética , Testículo/anormalidades
19.
Acta Paediatr ; 96(5): 638-43, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17326760

RESUMO

AIM: To reach consensus among specialists from the Nordic countries on the present state-of-the-art in treatment of undescended testicles. METHODS: A group of specialists in testicular physiology, paediatric surgery/urology, endocrinology, andrology, pathology and anaesthesiology from all the Nordic countries met for two days. Before the meeting, reviews of the literature had been prepared by the participants. RECOMMENDATIONS: The group came to the following unanimous conclusions: (1) In general, hormonal treatment is not recommended, considering the poor immediate results and the possible long term adverse effects on spermatogenesis. Thus, surgery is to be preferred. (2) Orchiopexy should be done between 6 and 12 months of age, or upon diagnosis, if that occurs later. (3) Orchiopexy before age one year should only be done at centres with both paediatric surgeons/urologists and paediatric anaesthesiologists. (4) If a testis is found to be undescended at any age after 6 months, the patient should be referred for surgery--to paediatric rather than general surgeons/urologists if the boy is less than one year old or if he has bilateral or non-palpable testes, or if he has got relapse of cryptorchidism.


Assuntos
Criptorquidismo/cirurgia , Anestesia , Criança , Criptorquidismo/tratamento farmacológico , Criptorquidismo/embriologia , Árvores de Decisões , Humanos , Lactente , Masculino
20.
J Steroid Biochem Mol Biol ; 102(1-5): 184-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17049842

RESUMO

Regulation of testicular descent is hormonally regulated, but the reasons for maldescent remain unknown in most cases. The main regulatory hormones are Leydig cell-derived testosterone and insulin-like factor 3 (INSL3). Luteinizing hormone (LH) stimulates the secretion of these hormones, but the secretory responses to LH are different: INSL3 secretion increases slowly and may reflect the LH dependent differentiated status of Leydig cells, whereas testosterone response to LH is immediate. Testosterone contributes to the involution of the suspensory ligament and to the inguinoscrotal phase of the descent, while INSL3 acts mainly in transabdominal descent by stimulating the growth of the gubernaculum. INSL3 acts through a G-protein coupled receptor LGR8. In the absence of either INSL3 or LGR8 mice remain cryptorchid. In humans only few INSL3 mutations have been described, whereas LGR8 mutations may cause some cases of undescended testis. Similarly, androgen insensitivity or androgen deficiency can cause cryptorchidism. Estrogens have been shown to down regulate INSL3 and thereby cause maldescent. Thus, a reduced androgen-estrogen ratio may disturb testicular descent. Environmental effects changing the ratio can thereby influence cryptorchidism rate. Estrogens and anti-androgens cause cryptorchidism in experimental animals. In our cohort study we found higher LH/testosterone ratios in 3-month-old cryptorchid boys than in normal control boys, suggesting that cryptorchid testes are not cabable of normal hormone secretion without increased gonadotropin drive. This may be either the cause or consequence of cryptorchidism. Some phthalates act as anti-androgens and cause cryptorchidism in rodents. In our human material we found an association of a high phthalate exposure with a high LH/testosterone ratio. We hypothesize that an exposure to a mixture of chemicals with anti-androgenic or estrogenic properties (either their own activity or their effect on androgen-estrogen ratio) may be involved in cryptorchidism.


Assuntos
Meio Ambiente , Hormônios/farmacologia , Testículo/crescimento & desenvolvimento , Animais , Humanos , Masculino , Testículo/efeitos dos fármacos
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