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OBJECTIVE: To determine the influence of serum sodium on physical, psychologic and sexual function. METHODS: This is a cross-sectional survey on 3340 community-dwelling men aged 40-79 years from a prospective cohort study in eight European countries, the European Male Ageing Study (EMAS). Participants filled-out the Short Form-36 (SF-36), the Physical Activity Scale for the Elderly (PASE), and the EMAS sexual function questionnaire. For all the analyses, serum sodium corrected for glycaemia ([Na+]G) was used. RESULTS: The relationship between [Na+]G and SF-36 physical function score (F = 3.99; p = 0.01), SF-36 mental health score (F = 7.69; p < 0.001), and PASE score (F = 14.95; p < 0.001) were best described by a quadratic equation, with worse scores for [Na+]G in either the lowest or the highest ends of the range. After dividing the sample into [Na+]G < 136 mmol/L (n = 81), 136-147 mmol/L (n = 3223) and > 147 mmol/L (n = 36), linear regression analyses with linear spline functions adjusted for confounders did not confirm these relationships. Similarly, erectile dysfunction and [Na+]G, were in a quadratic relationship (F = 9.00; p < 0.001). After adjusting for confounders, the linear regression with spline functions denoted a significantly worsened erectile function for increases in serum [Na+]G > 147 mmol/L (B = 0.15 [0.04;0.26], p < 0.01) but no relationship with [Na+]G < 136 mmol/L. Likewise, the relationship of [Na+]G with concerns about sexual dysfunction was confirmed only for men with serum [Na+]G > 147 mmol/L. CONCLUSIONS: This is the first study supporting an association between [Na+]G and sexual function. A worsening of erection and concerns about sexual function were observed for the highest values of [Na+]G, independently of other relevant factors.
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Hipernatremia , Hiponatremia , Anciano , Humanos , Masculino , Estudios Transversales , Estudios Prospectivos , SodioRESUMEN
We examined cross-sectional associations of metabolic syndrome and its components with male bone turnover, density and structure. Greater bone mass in men with metabolic syndrome was related to their greater body mass, whereas hyperglycaemia, hypertriglyceridaemia or impaired insulin sensitivity were associated with lower bone turnover and relative bone mass deficits. INTRODUCTION: Metabolic syndrome (MetS) has been associated with lower bone turnover and relative bone mass or strength deficits (i.e. not proportionate to body mass index, BMI), but the relative contributions of MetS components related to insulin sensitivity or obesity to male bone health remain unclear. METHODS: We determined cross-sectional associations of MetS, its components and insulin sensitivity (by homeostatic model assessment-insulin sensitivity (HOMA-S)) using linear regression models adjusted for age, centre, smoking, alcohol, and BMI. Bone turnover markers and heel broadband ultrasound attenuation (BUA) were measured in 3129 men aged 40-79. Two centres measured total hip, femoral neck, and lumbar spine areal bone mineral density (aBMD, n = 527) and performed radius peripheral quantitative computed tomography (pQCT, n = 595). RESULTS: MetS was present in 975 men (31.2 %). Men with MetS had lower ß C-terminal cross-linked telopeptide (ß-CTX), N-terminal propeptide of type I procollagen (PINP) and osteocalcin (P < 0.0001) and higher total hip, femoral neck, and lumbar spine aBMD (P ≤ 0.03). Among MetS components, only hypertriglyceridaemia and hyperglycaemia were independently associated with PINP and ß-CTX. Hyperglycaemia was negatively associated with BUA, hypertriglyceridaemia with hip aBMD and radius cross-sectional area (CSA) and stress-strain index. HOMA-S was similarly associated with PINP and ß-CTX, BUA, and radius CSA in BMI-adjusted models. CONCLUSIONS: Men with MetS have higher aBMD in association with their greater body mass, while their lower bone turnover and relative deficits in heel BUA and radius CSA are mainly related to correlates of insulin sensitivity. Our findings support the hypothesis that underlying metabolic complications may be involved in the bone's failure to adapt to increasing bodily loads in men with MetS.
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Remodelación Ósea , Huesos/patología , Hiperglucemia/complicaciones , Resistencia a la Insulina , Síndrome Metabólico/complicaciones , Adulto , Anciano , Envejecimiento , Densidad Ósea , Estudios Transversales , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Social and lifestyle influences on age-related changes in body morphology are complex because lifestyle and physiological response to social stress can affect body fat differently. OBJECTIVE: In this study, we examined the associations of socioeconomic status (SES) and lifestyle factors with BMI and waist circumference (WC) in middle-aged and elderly European men. DESIGN AND SETTING: A cross-sectional study of 3319 men aged 40-79 years recruited from eight European centres. OUTCOMES: We estimated relative risk ratios (RRRs) of overweight/obesity associated with unfavourable SES and lifestyles. RESULTS: The prevalence of BMI ≥ 30 kg/m(2) or WC ≥ 102 cm rose linearly with age, except in the eighth decade when high BMI, but not high WC, declined. Among men aged 40-59 years, compared with non-smokers or most active men, centre and BMI-adjusted RRRs for having a WC between 94 and 101.9 cm increased by 1.6-fold in current smokers, 2.7-fold in least active men and maximal at 2.8-fold in least active men who smoked. Similar patterns but greater RRRs were observed for men with WC ≥ 102 cm, notably 8.4-fold greater in least active men who smoked. Compared with men in employment, those who were not in employment had increased risk of having a high WC by 1.4-fold in the 40-65 years group and by 1.3-fold in the 40-75 years group. These relationships were weaker among elderly men. CONCLUSION: Unfavourable SES and lifestyles associate with increased risk of obesity, especially in middle-aged men. The combination of inactivity and smoking was the strongest predictor of high WC, providing a focus for health promotion and prevention at an early age.
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Envejecimiento/patología , Estilo de Vida , Obesidad/diagnóstico , Obesidad/economía , Adulto , Anciano , Estudios Transversales , Europa (Continente)/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Factores de Riesgo , Factores SocioeconómicosRESUMEN
OBJECTIVE: Reduced sex hormone-binding globulin (SHBG) concentration predicts insulin resistance and type 2 diabetes, but its association with cardiovascular disease (CVD) risk is unclear. We examined the association between SHBG and cardiovascular risk factors, independently of total testosterone (TT), in young men. DESIGN: Observational, cross-sectional study. SETTING: General community. PARTICIPANTS: The study included 2716 men aged 31 years in the Northern Finland Birth Cohort in 1996 with clinical examination data and fasting blood samples. OUTCOME VARIABLES: Blood pressure (BP), lipids and C-reactive protein (CRP) as biological CVD risk markers. RESULTS: SHBG concentration was significantly and inversely related to systolic and diastolic BP, triglycerides and CRP, but positively to HDL cholesterol after adjusting for insulin, BMI, waist circumference, smoking, education and physical activity (all P<0.05). These linearly graded associations persisted with additional adjustment for TT. SHBG was significantly associated with total cholesterol only with adjustment for covariates and TT (P<0.05). The direction and magnitude of associations between TT and risk factors were variable, but further adjustment for insulin, adiposity and SHBG showed positive associations between TT and BP, total and LDL-cholesterol and triglycerides and an inverse association with CRP (all P<0.05), but its relation with HDL-cholesterol was no longer significant. CONCLUSIONS: In this cohort of young adult men, higher SHBG concentration was associated with a more favourable CVD risk profile, independently of TT. SHBG concentration modified the associations of TT with CVD risk factors.
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Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/epidemiología , Globulina de Unión a Hormona Sexual/análisis , Testosterona/sangre , Adulto , Estudios de Cohortes , Finlandia/epidemiología , Humanos , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/epidemiología , Factores de Riesgo , Globulina de Unión a Hormona Sexual/metabolismoRESUMEN
CONTEXT: Late-onset hypogonadism (LOH) has recently been defined as a syndrome in middle-aged and elderly men reporting sexual symptoms in the presence of low T. The natural history of LOH, especially its relationship to mortality, is currently unknown. OBJECTIVE: The aim of this study was to clarify the associations between LOH, low T, and sexual symptoms with mortality in men. DESIGN, SETTING, AND PARTICIPANTS: Prospective data from the European Male Aging Study (EMAS) on 2599 community-dwelling men aged 40-79 years in eight European countries was used for this study. MAIN OUTCOME MEASURE(S): All-cause, cardiovascular, and cancer-related mortality was measured. RESULTS: One hundred forty-seven men died during a median follow-up of 4.3 years. Fifty-five men (2.1%) were identified as having LOH (31 moderate and 24 severe). After adjusting for age, center, body mass index (BMI), current smoking, and poor general health, compared with men without LOH, those with severe LOH had a 5-fold [hazard ratio (HR) 5.5; 95% confidence interval (CI) 2.7, 11.4] higher risk of all-cause mortality. Compared with eugonadal men, the multivariable-adjusted risk of mortality was 2-fold higher in those with T less than 8 nmol/L (irrespective of symptoms; HR 2.3; 95% CI 1.2, 4.2) and 3-fold higher in those with three sexual symptoms (irrespective of serum T; compared with asymptomatic men; HR 3.2; 95% CI 1.8, 5.8). Similar risks were observed for cardiovascular mortality. CONCLUSIONS: Severe LOH is associated with substantially higher risks of all-cause and cardiovascular mortality, to which both the level of T and the presence of sexual symptoms contribute independently. Detecting low T in men presenting with sexual symptoms offers an opportunity to identify a small subgroup of aging men at particularly high risk of dying.
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Envejecimiento , Hipogonadismo/mortalidad , Adulto , Edad de Inicio , Anciano , Envejecimiento/sangre , Enfermedades Cardiovasculares/mortalidad , Europa (Continente)/epidemiología , Humanos , Hipogonadismo/sangre , Masculino , Persona de Mediana Edad , Testosterona/sangreRESUMEN
OBJECTIVE: Health and lifestyle factors are associated with variations in serum testosterone levels in ageing men. However, it remains unclear how age-related changes in testosterone may be attenuated by lifestyle modifications. The objective was to investigate the longitudinal relationships between changes in health and lifestyle factors with changes in hormones of the reproductive endocrine axis in ageing men. DESIGN: A longitudinal survey of 2736 community-dwelling men aged 40-79 years at baseline recruited from eight centres across Europe. Follow-up assessment occurred mean (±S.D.) 4.4±0.3 years later. RESULTS: Paired testosterone results were available for 2395 men. Mean (±S.D.) annualised hormone changes were as follows: testosterone -0.1±0.95â nmol/l; free testosterone (FT) -3.83±16.8 âpmol/l; sex hormone-binding globulin (SHBG) 0.56±2.5â nmol/l and LH 0.08±0.57â U/l. Weight loss was associated with a proportional increase, and weight gain a proportional decrease, in testosterone and SHBG. FT showed a curvilinear relationship to weight change; only those who gained or lost ≥15% of weight showed a significant change (in the same direction as testosterone). Smoking cessation was associated with a greater decline in testosterone than being a non-smoker, which was unrelated to weight change. Changes in number of comorbid conditions or physical activity were not associated with significant alterations in hypothalamic-pituitary-testicular (HPT) axis function. CONCLUSIONS: Body weight and lifestyle factors influence HPT axis function in ageing. Weight loss was associated with a rise, and weight gain a fall, in testosterone, FT and SHBG. Weight management appears to be important in maintaining circulating testosterone in ageing men, and obesity-associated changes in HPT axis hormones are reversible following weight reduction.
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Envejecimiento/fisiología , Sistema Hipotálamo-Hipofisario/fisiología , Estilo de Vida , Testículo/fisiología , Aumento de Peso , Pérdida de Peso , Adulto , Anciano , Envejecimiento/sangre , Estudios de Cohortes , Europa (Continente) , Estudios de Seguimiento , Humanos , Sistema Hipotálamo-Hipofisario/crecimiento & desarrollo , Sistema Hipotálamo-Hipofisario/metabolismo , Estudios Longitudinales , Hormona Luteinizante/sangre , Hormona Luteinizante/metabolismo , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Globulina de Unión a Hormona Sexual/análisis , Globulina de Unión a Hormona Sexual/metabolismo , Cese del Hábito de Fumar , Testículo/crecimiento & desarrollo , Testículo/metabolismo , Testosterona/sangre , Testosterona/metabolismoRESUMEN
AIMS: The aim of this study was to determine if genetic variation in the pain-modulating gene DREAM and its pathway genes influence susceptibility to reporting musculoskeletal pain in the population. METHODS: Pairwise tag single nucleotide polymorphisms (SNPs) in DREAM, PDYN and OPRK1 were genotyped in a UK population-based discovery cohort in whom pain was assessed using blank body manikins at three time points. Depression and anxiety symptoms were assessed at the first time point. Zero-inflated negative binomial regression was used to test for association between SNPs and the maximum number of pain sites reported (0-29) across the three time points. Significantly associated SNPs (p < 0.05) were subsequently genotyped for validation in a cohort of European men with pain assessed at two time points. RESULTS: Thirty-five SNPs were genotyped in 1055 subjects, of whom 83% reported pain, in the discovery cohort. SNPs in each gene were associated with the maximum number of pain sites reported, were independent of symptoms of anxiety and depression and had a significant cumulative effect (p = 7.0 × 10(-5) ). Significantly associated SNPs were successfully genotyped in 1733 men, 76% of whom reported pain, in the validation cohort, but did not show significant association with the number of pain sites. CONCLUSIONS: Genetic variation in the DREAM pathway genes was associated with the extent of pain reporting in a population-based cohort. These findings were not replicated in a single independent cohort; however, given the potential of this pathway as a therapeutic target, further investigation in additional cohorts is warranted.
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Encefalinas/genética , Proteínas de Interacción con los Canales Kv/genética , Dolor Musculoesquelético/genética , Precursores de Proteínas/genética , Receptores Opioides kappa/genética , Proteínas Represoras/genética , Adulto , Anciano , Ansiedad/epidemiología , Ansiedad/genética , Estudios de Cohortes , Comorbilidad , Depresión/epidemiología , Depresión/genética , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Dolor Musculoesquelético/epidemiología , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
OBJECTIVE: It has been suggested that elevated levels of C-reactive protein (CRP) might interfere with leptin signalling and contribute to leptin resistance. Our aim was to assess whether plasma levels of CRP influence leptin resistance in humans, and our hypothesis was that CRP levels would modify the cross-sectional relationships between leptin and measures of adiposity. DESIGN AND METHODS: W assessed four measures of adiposity: BMI, waist circumference, fat mass and body fat (%) in 2113 British Regional Heart Study (BRHS) men (mean (s.d.) age 69 (5) years), with replication in 760 (age 69 (6) years) European Male Ageing Study (EMAS) subjects. RESULTS: IN BRHS subjects, leptin correlated with CRP (SPEARMAN'S R=0.22, P0.0001). Leptin and crp correlated with all four measures of adiposity (R VALUE RANGE: 0.22-0.57, all P<0.0001). Age-adjusted mean levels for adiposity measures increased in relation to leptin levels, but CRP level did not consistently influence the ß-coefficients of the regression lines in a CRP-stratified analysis. In BRHS subjects, the BMI vs leptin relationship demonstrated a weak statistical interaction with CRP (P=0.04). We observed no similar interaction in EMAS subjects and no significant interactions with other measures of adiposity in BRHS or EMAS cohorts. CONCLUSION: We have shown that plasma CRP has little influence on the relationship between measures of adiposity and serum leptin levels in these middle-aged and elderly male European cohorts. This study provides epidemiological evidence against CRP having a significant role in causing leptin resistance.
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Proteína C-Reactiva/metabolismo , Leptina/sangre , Tejido Adiposo/anatomía & histología , Adiposidad , Adulto , Anciano , Índice de Masa Corporal , Estudios de Cohortes , Resistencia a Medicamentos , Humanos , Masculino , Persona de Mediana Edad , Circunferencia de la CinturaRESUMEN
OBJECTIVES: Adapt a measure of frailty for use in a cohort study of European men and explore relationships with age, health related quality of life and falls. DESIGN: Longitudinal cohort study. SETTING: 8 European centers. PARTICIPANTS: 3047 men aged 40-79 participating in the European Male Ageing Study (EMAS). MEASUREMENTS: Frailty was assessed using an adaptation of the Cardiovascular Health Study criteria. Health related quality of life was evaluated using the Rand Short Form-36 (SF-36) questionnaire which comprises both mental and physical component scores. Self reported falls in the preceding 12 months were recorded at 2-year follow-up. RESULTS: 78 men (2.6%) were classified as frail (≥3 criteria) and 821 (26.9%) as prefrail (1-2 criteria). The prevalence of frailty increased from 0.1% in men aged 40-49 up to 6.8% in men aged 70-79. Compared to robust men, both prefrail and frail men had lower health related quality of life. Frailty was more strongly associated with the physical than mental subscales of the SF-36. Frailty was associated with higher risk of falls OR (95% CI) 2.92 (1.52, 5.59). CONCLUSIONS: Frailty, assessed by the EMAS criteria, increased in prevalence with age and was related to poorer health related quality of life and higher risk of falls in middle-aged and older European men. These criteria may help to identify a vulnerable subset of older men.
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The role of thyroid hormones in the control of erectile functioning has been only superficially investigated. The aim of the present study was to investigate the association between thyroid and erectile function in two different cohorts of subjects. The first one derives from the European Male Ageing Study (EMAS study), a multicentre survey performed on a sample of 3369 community-dwelling men aged 40-79 years (mean 60 ± 11 years). The second cohort is a consecutive series of 3203 heterosexual male patients (mean age 51.8 ± 13.0 years) attending our Andrology and Sexual Medicine Outpatient Clinic for sexual dysfunction at the University of Florence (UNIFI study). In the EMAS study all subjects were tested for thyroid-stimulating hormone (TSH) and free thyroxine (FT4). Similarly, TSH levels were checked in all patients in the UNIFI study, while FT4 only when TSH resulted outside the reference range. Overt primary hyperthyroidism (reduced TSH and elevated FT4, according to the reference range) was found in 0.3 and 0.2% of EMAS and UNIFI study respectively. In both study cohorts, suppressed TSH levels were associated with erectile dysfunction (ED). Overt hyperthyroidism was associated with an increased risk of severe erectile dysfunction (ED, hazard ratio = 14 and 16 in the EMAS and UNIFI study, respectively; both p < 0.05), after adjusting for confounding factors. These associations were confirmed in nested case-control analyses, comparing subjects with overt hyperthyroidism to age, BMI, smoking status and testosterone-matched controls. Conversely, no association between primary hypothyroidism and ED was observed. In conclusion, erectile function should be evaluated in all individuals with hyperthyroidism. Conversely, assessment of thyroid function cannot be recommended as routine practice in all ED patients.
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Disfunción Eréctil/etiología , Hipertiroidismo/complicaciones , Tirotropina/sangre , Tiroxina/sangre , Adulto , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Estudios Transversales , Humanos , Hipotiroidismo/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Fumar/efectos adversosAsunto(s)
Andrología , Publicaciones Periódicas como Asunto , Humanos , Masculino , Sociedades CientíficasRESUMEN
SUMMARY: The influence of age and sex steroids on bone density and geometry of the radius was examined in two European Caucasian populations. Age-related change in bone density and geometry was observed. In older men, bioavailable oestradiol may play a role in the maintenance of cortical and trabecular bone mineral density (BMD). INTRODUCTION: To examine the effect of age and sex steroids on bone density and geometry of the radius in two European Caucasian populations. METHODS: European Caucasian men aged 40-79 years were recruited from population registers in two centres: Manchester (UK) and Leuven (Belgium), for participation in the European Male Ageing Study. Total testosterone (T) and oestradiol (E(2)) were measured by mass spectrometry and the free and bioavailable fractions calculated. Peripheral quantitative computed tomography was used to scan the radius at distal (4%) and midshaft (50%) sites. RESULTS: Three hundred thirty-nine men from Manchester and 389 from Leuven, mean ages 60.2 and 60.0 years, respectively, participated. At the 50% radius site, there was a significant decrease with age in cortical BMD, bone mineral content (BMC), cortical thickness, and muscle area, whilst medullary area increased. At the 4% radius site, trabecular and total volumetric BMD declined with age. Increasing bioavailable E(2) (bioE(2)) was associated with increased cortical BMD (50% radius site) and trabecular BMD (4% radius site) in Leuven, but not Manchester, men. This effect was predominantly in those aged 60 years and over. In older Leuven men, bioavailable testosterone (Bio T) was linked with increased cortical BMC, muscle area and SSI (50% radius site) and total area (4% radius site). CONCLUSIONS: There is age-related change in bone density and geometry at the midshaft radius in middle-aged and elderly European men. In older men bioE(2) may maintain cortical and trabecular BMD. BioT may influence bone health through associations with muscle mass and bone area.
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Envejecimiento/fisiología , Densidad Ósea/fisiología , Hormonas Esteroides Gonadales/fisiología , Radio (Anatomía)/fisiología , Adulto , Anciano , Estudios Transversales , Estradiol/sangre , Estradiol/fisiología , Hormonas Esteroides Gonadales/sangre , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Radio (Anatomía)/anatomía & histología , Testosterona/sangre , Testosterona/fisiologíaRESUMEN
Evidence from clinic-based studies suggests that the fibromyalgia syndrome (FMS) is associated with impairment in cognitive function though the mechanism is unclear. The aim of this analysis was to determine whether there is a similar association between chronic widespread pain (CWP), a cardinal feature of FMS, and impaired cognition in a community setting. Men (n=3369, 40-79 years) were recruited from population registers in eight centres for participation in the European Male Ageing Study (EMAS). The subjects completed a pain questionnaire and pain manikin, with the presence of CWP defined using the American College of Rheumatology criteria. The cognitive functions measured were visuospatial-constructional ability and visual memory (Rey-Osterrieth Complex Figure [ROCF]); visual recognition (Camden Topographical Recognition Memory test [CTRM]); and psychomotor processing speed (Digit-Symbol Substitution test [DSST]). We restricted our analysis to those subjects reporting pain that satisfied the criteria for CWP and those who were pain free. Of these 1539 men [mean (SD) age 60 (11) years], 266 had CWP. All cognitive test scores declined cross-sectionally with age (P<0.05). In age-adjusted linear regressions men with CWP had a lower DSST score (ß=-2.4, P<0.001) compared to pain-free subjects. After adjustment for lifestyle and health factors the association between pain status and the DSST score was attenuated but remained significant (ß=-1.02, P=0.04). There was no association between CWP and the ROCF-copy, ROCF-recall or CTRM scores. CWP is associated with slower psychomotor processing speed among community-dwelling European men. Prospective studies are required to confirm this observation and explore possible mechanisms for the association.
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Envejecimiento , Trastornos del Conocimiento/fisiopatología , Dolor/fisiopatología , Dolor/psicología , Adulto , Anciano , Enfermedad Crónica , Trastornos del Conocimiento/epidemiología , Estudios de Cohortes , Europa (Continente)/epidemiología , Humanos , Aprendizaje/fisiología , Estilo de Vida , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Dolor/epidemiología , Estimulación Luminosa/métodos , Desempeño Psicomotor/fisiología , Tiempo de Reacción , Valores de Referencia , Características de la Residencia , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Percepción Visual/fisiología , Población BlancaRESUMEN
Growing evidence suggests the tachykinin neurokinin B (NKB) may modulate gonadotrophin secretion and play a role in sex-steroid feedback within the reproductive axis. NKB signalling has recently been identified as being necessary for normal human reproductive function, although the precise mechanisms underpinning this role remain to be established. We have used rodents to explore further the role of NKB within the reproductive axis. In particular, we have studied its interactions with kisspeptin, a neuropeptide essential for reproductive function in rodent and human with close anatomical links to NKB within the hypothalamus. Intraperitoneal administration of NKB (50 nmol) to male mice had no effect on circulating luteinsing hormone (LH) levels and, although i.p. kisspeptin (15 nmol) increased LH five-fold, co-administration of NKB and kisspeptin was indistinguishable from kisspeptin alone. Intracerebroventricular administration of NKB (10 nmol) to male mice also had no effect on LH levels, with 1 nmol kisspeptin i.c.v. significantly increasing LH compared to control (0.37 +/- 0.18 versus 5.11 +/- 0.28 ng/ml, respectively). Interestingly, i.c.v. co-administration of NKB and kisspeptin caused a significant increase in LH concentrations compared to kisspeptin alone (8.96 +/- 1.82 versus 5.11 +/- 0.28 ng/ml respectively). We used hypothalamic explants from rats to assess the effect of NKB on gonadotrpohin-releasing hormone (GnRH) secretion ex vivo. Doses of NKB up to 1000 nm failed to stimulate GnRH secretion, whereas 100 nm kisspeptin robustly increased GnRH secretion. Of note, co-administration of NKB with kisspeptin abrogated the effect of kisspeptin, producing no GnRH release above basal state. Finally, we analysed the expression of Tac2/Tacr3 (genes encoding NKB and NK3R, respectively) within the arcuate nucleus in different nutritional states. After a 48-h fast, the expression of both Tac2 and Tacr3 showed a significant increase, in contrast to levels of Kiss1 and Kiss1r mRNA, which remained unchanged. In male rodent models, NKB and kisspeptin have different effects upon gonadotrophin release and appear to interact in a complex manner.
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Hormona Luteinizante/metabolismo , Neuroquinina B/farmacología , Proteínas/farmacología , Animales , Núcleo Arqueado del Hipotálamo/efectos de los fármacos , Núcleo Arqueado del Hipotálamo/metabolismo , Ayuno/metabolismo , Hormona Liberadora de Gonadotropina/sangre , Hormona Liberadora de Gonadotropina/metabolismo , Kisspeptinas , Hormona Luteinizante/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Neuroquinina B/administración & dosificación , Precursores de Proteínas/biosíntesis , Proteínas/administración & dosificación , Ratas , Ratas Wistar , Receptores de Taquicininas/biosíntesis , Taquicininas/biosíntesisRESUMEN
SUMMARY: The influence of sex steroids on calcaneal quantitative ultrasound (QUS) parameters was assessed in a population sample of middle-aged and elderly European men. Higher free and total E(2) though not testosterone, were independently associated with higher QUS parameters. INTRODUCTION: The aim of this study was to investigate the association between QUS parameters and sex steroids in middle-aged and elderly European men. METHODS: Three thousand one hundred forty-one men aged between 40 and 79 years were recruited from eight European centres for participation in a study of male ageing: the European Male Ageing Study. Subjects were invited by letter to attend for an interviewer-administered questionnaire, blood sample and QUS of the calcaneus (Hologic-SAHARA). Blood was assessed for sex steroids including oestradiol (E(2)), testosterone (T), free and bio-available E(2) and T and sex hormone binding globulin (SHBG). RESULTS: Serum total T was not associated with any of the QUS parameters. Free T and both free and total E(2) were positively related to all QUS readings, while SHBG concentrations were negatively associated. These relationships were observed in both older and younger (<60 years) men. In a multivariate model, after adjustment for age, centre, height, weight, physical activity levels and smoking, free E(2) and SHBG, though not free T, remained independently associated with the QUS parameters. After further adjustment for IGF-1, however, the association with SHBG became non-significant. CONCLUSION: Higher free and total E(2) are associated with bone health not only among the elderly but also middle-aged European men.
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Calcáneo/diagnóstico por imagen , Hormonas Esteroides Gonadales/sangre , Adulto , Anciano , Envejecimiento/sangre , Envejecimiento/fisiología , Estatura/fisiología , Peso Corporal/fisiología , Calcáneo/fisiología , Estradiol/sangre , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Globulina de Unión a Hormona Sexual/metabolismo , Fumar/sangre , Testosterona/sangre , UltrasonografíaRESUMEN
Apart from condoms and vasectomy, modern contraceptive methods for men are still not available. Besides hormonal approaches to stop testicular sperm production, the post-meiotic blockage of epididymal sperm maturation carries lots of promise. Microarray and proteomics techniques and libraries of expressed sequence tags, in combination with digital differential display tools and publicly available gene expression databases, are being currently used to identify and characterize novel epididymal proteins as putative targets for male contraception. The data reported indicate that these technologies provide complementary information for the identification of novel highly expressed genes in the epididymis. Deleting the gene of interest by targeted ablation technology in mice or using immunization against the cognate protein are the two preferred methods to functionally validate the function of novel genes in vivo. In this review, we summarize the current knowledge of several epididymal proteins shown either in vivo or in vitro to be involved in the epididymal sperm maturation. These proteins include CRISP1, SPAG11e, DEFB126, carbonyl reductase P34H, CD52, and GPR64. In addition, we introduce novel proteinases and protease inhibitor gene families with potentially important roles in regulating the sperm maturation process. Furthermore, potential contraceptive strategies as well as delivery methods will be discussed. Despite the progress made in recent years, further studies are needed to reveal further details in the epididymal sperm maturation process and the factors involved, in order to facilitate the development of new epididymal contraceptives.
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Anticoncepción/métodos , Anticoncepción/tendencias , Anticonceptivos Masculinos , Proteínas Secretorias del Epidídimo , Animales , Eliminación de Gen , Humanos , Masculino , Modelos Animales , Péptido Hidrolasas/genética , Inhibidores de Proteasas , Maduración del Esperma/fisiologíaRESUMEN
OBJECTIVES: To determine whether among middle-aged and elderly men there is evidence of international differences in the prevalence of chronic widespread pain (CWP) and whether any such differences could be explained by psychological, psychosocial factors or differences in physical health status. METHODS: The European Male Ageing Study (EMAS) sampled from population registers in cities (centres) of eight European countries. Each centre recruited an age-stratified sample of men aged 40-79 years. Information on pain was collected by questionnaire and subjects were classified according to whether they satisfied the American College of Rheumatology definition of CWP. Information was collected on social status, mental health, recent life events and co-morbidities. RESULTS: Across all centres 3963 subjects completed a study questionnaire, with participation rates ranging from 24% in Hungary to 72% in Estonia. There were significant differences in prevalence: between 5% and 7% in centres in Italy, England, Belgium and Sweden, 9-15% in centres in Spain, Poland and Hungary and 15% in Estonia. There were strong relationships between poor mental health, adverse recent life events, co-morbidities and CWP. Adjustment for these factors explained between half and all of the excess risk in the eastern European centres: the excess risk in Poland was explained (odds ratio (OR) 1.1, 95% CI 0.9 to 1.2) but there remained excess risk in Hungary (OR 1.6, 95% CI 1.4 to 1.8) and Estonia (OR 2.6, 95% CI 2.2 to 2.9). CONCLUSIONS: This study is the first directly to compare the occurrence of CWP internationally. There is an excess prevalence in countries of eastern Europe and this excess is associated with adverse psychosocial factors as well as poorer psychological and physical health.
Asunto(s)
Fibromialgia/epidemiología , Dolor/epidemiología , Adulto , Anciano , Enfermedad Crónica , Métodos Epidemiológicos , Europa (Continente)/epidemiología , Fibromialgia/etiología , Fibromialgia/psicología , Humanos , Acontecimientos que Cambian la Vida , Masculino , Trastornos Mentales/complicaciones , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Dolor/etiología , Dolor/psicología , Dimensión del Dolor/métodosRESUMEN
This short review provides an update on the new information that has become available in the recent years about mutations and polymorphisms in the genes for gonadotropins and their receptors. Combining the types and locations of the mutations, their phenotypic effects, and the recently emerged information about the crystal structure of these molecules is providing us with increasingly detailed picture about the structure-function relationships of gonadotropin action.
Asunto(s)
Hormona Folículo Estimulante/genética , Hormona Luteinizante/genética , Mutación/genética , Polimorfismo Genético/genética , Receptores de HFE/genética , Receptores de HL/genética , Secuencia de Aminoácidos , HumanosRESUMEN
BACKGROUND: The contribution of the adrenal glands to the total circulating steroid pool in women is not well known. There is evidence that human adrenals express the LH receptor gene and that LH may affect adrenal androgen secretion. METHODS: HCG stimulation tests (a single dose of 5000 IU i.m.) were performed in women at reproductive age (group 1, n = 6, age 21--39 years) before and after treatment with a GnRH agonist for 3 weeks, and in oophorectomized post-menopausal women (group 2, n = 6, 47--59 years) during and after estrogen replacement therapy (ERT). RESULTS: HCG did not stimulate the secretion of cortisol, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS) in group 2. In contrast, in group 1, the basal concentrations of serum 17-hydroxyprogesterone (17-OHP), androstenedione, testosterone and estradiol (E(2)) were stimulated significantly (17-OHP 105%, androstenedione 31%, testosterone 20%, E(2) 136%) by HCG, and the treatment with GnRH agonist decreased the responses. The basal serum concentrations of these steroids were significantly lower in oophorectomized women (17-OHP 57%, androstenedione 46%, testosterone 25%), and HCG did not increase these levels. It can be approximated that the ovarian contribution to the circulating levels of 17-OHP, androstenedione and testosterone is 25--30%, and that the adrenals are the primary source of cortisol, DHEA and DHEAS. CONCLUSION: LH/HCG does not have a major role in the regulation of adrenal steroid synthesis in endocrinologically healthy women.
Asunto(s)
Glándulas Suprarrenales/metabolismo , Gonadotropina Coriónica/fisiología , Hormonas/biosíntesis , Hormona Luteinizante/fisiología , Ovario/metabolismo , Adulto , Femenino , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Persona de Mediana Edad , Concentración Osmolar , Ovariectomía , Posmenopausia/metabolismo , Valores de ReferenciaRESUMEN
Activin signals via complexes of type I (50-55 kDa) and II (70-75 kDa) activin receptors, but the mechanism of inhibin action is unclear. Proposed models range from an anti-activin action at the type II activin receptor to independent actions involving putative inhibin receptors. Two membrane-embedded proteoglycans, betaglycan and p120, have recently been implicated in inhibin binding, but neither appears to be a signalling receptor. The present studies on primary cultures of rat pituitary and adrenal cells, and several murine and human cell lines were undertaken to characterise inhibin binding to its physiological targets. High affinity binding of inhibin to the primary cultures and several of the cell lines, like that previously described for ovine pituitary cells, was saturable and reversible. Scatchard analysis revealed two classes of binding sites (K(d) of 40-400 and 500-5000 pM, respectively). Affinity labelling identified [125I]inhibin binding proteins with apparent molecular weights of 41, 74, 114 and >170 kDa in all cell types that displayed high affinity, high capacity binding of inhibin. Additional labelling of a 124 kDa species was evident in gonadal TM3 and TM4 cell lines. In several cases, activin (> or =20 nM) competed poorly or not at all for binding to these proteins. The 74, 114 and >170 kDa inhibin binding proteins in TM3 and TM4 cells were immunoprecipitated by an anti-betaglycan antiserum. These three proteins correspond in size to the activin receptor type II and the core protein and glycosylated forms of betaglycan, respectively, that have been proposed to mediate anti-activin actions of inhibin, but the identity of the 74 kDa species is yet to be confirmed. Studies of [125I]inhibin binding kinetics and competition for affinity labelling of individual binding proteins in several cell lines suggest these three species and the 41 and 124 kDa proteins form a high affinity inhibin binding complex. In summary, common patterns of inhibin binding and affinity labelling were observed in inhibin target cells. Novel inhibin binding proteins of around 41 and 124 kDa were implicated in the high affinity binding of inhibin to cells from several sources.