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Ketchem JM, Bowman EJ, Isales CM. Male sex hormones, aging, and inflammation. Biogerontology 2023; 24:1-25. [PMID: 36596999 PMCID: PMC9810526 DOI: 10.1007/s10522-022-10002-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/15/2022] [Indexed: 01/05/2023]
Abstract
Adequate levels of androgens (eugonadism), and specifically testosterone, are vital compounds for male quality of life, longevity, and positive health outcomes. Testosterone exerts its effects by binding to the androgen receptor, which is expressed in numerous tissues throughout the body. Significant research has been conducted on the impact of this steroid hormone on skeletal, muscle and adipose tissues and on the cardiovascular, immune, and nervous systems. Testosterone levels have also been studied in relation to the impact of diseases, aging, nutrition and the environment on its circulating levels. Conversely, the impact of testosterone on health has also been evaluated with respect to its cardiac and vascular protective effects, body composition, autoimmunity and all-cause mortality. The male aging process results in decreasing testosterone levels over time. The exact mechanisms and impact of these changes in testosterone levels with age on health- and life-span are still not completely clear. Further research is needed to determine the optimal testosterone and androgen levels to protect from chronic age-related conditions such as frailty and osteoporosis.
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Affiliation(s)
- Justin M. Ketchem
- grid.410427.40000 0001 2284 9329Medical College of Georgia at Augusta University, Augusta, GA 30912 USA
| | | | - Carlos M. Isales
- grid.410427.40000 0001 2284 9329Departments of Medicine, Neuroscience and Regenerative Medicine, Augusta University, Augusta, GA 30912 USA
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Roelfsema F, Liu PY, Takahashi PY, Yang RJ, Veldhuis JD. Dynamic Interactions Between LH and Testosterone in Healthy Community-Dwelling Men: Impact of Age and Body Composition. J Clin Endocrinol Metab 2020; 105:5650390. [PMID: 31790144 PMCID: PMC7025815 DOI: 10.1210/clinem/dgz246] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 11/30/2019] [Indexed: 11/19/2022]
Abstract
BACKGROUND Aging is associated with diminished testosterone (Te) secretion, which may be attributed to Leydig cell dysfunction, decreased pituitary stimulation, and altered Te feedback. OBJECTIVE To study all regulatory nodes-gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and Leydig cell-in the same cohort of healthy men. STUDY DESIGN This was a placebo-controlled, blinded, prospectively randomized cross-over study in 40 men, age range 19 to 73 years, and body mass index (BMI) range 20 to 34.3 kg/m2. A submaximal dose of the GnRH antagonist ganirelix was used to assess outflow of GnRH, by calculating the difference between LH output during the control arm and ganirelix arm. Ketoconazole (a steroidogenic inhibitor) was used to estimate feedback, by the difference in LH output during the ketoconazole and control arm. High-dose ganirelix and repeated LH infusions were used to measure testicular responsivity. Blood sampling was performed at 10-minute intervals. RESULTS There were age-related, but not body composition-related decreases in estimated GnRH secretion, the feedback strength of Te on LH, and Leydig cell responsivity to LH, accompanied by changes in approximate entropy. Bioavailable Te levels were negatively related to both age and computed tomography (CT)-estimated abdominal visceral mass (AVF), without interaction between these variables. The LH response to a submaximal dose of GnRH was independent of age and AVF. CONCLUSION Advancing age is associated with (1) attenuated bioavailable Te secretion caused by diminished GnRH outflow and not by decreased GnRH responsivity of the gonadotrope, (2) diminished testicular responsivity to infused LH pulses, and (3) partial compensation by diminished Te feedback on central gonadotropic regulation.
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Affiliation(s)
- Ferdinand Roelfsema
- Department of Internal Medicine, Section Endocrinology and Metabolism, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter Y Liu
- Department of Medicine, David Geffen School of Medicine at UCLA, Harbor-UCLA Medical Center and Los Angeles Biomedical Research Institute, Los Angeles, California
| | - Paul Y Takahashi
- Department of Primary Care Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Rebecca J Yang
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota
| | - Johannes D Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota
- Correspondence: Johannes Veldhuis, MD, Endocrine Research Unit, Mayo Clinic, 200 First Street SW, Rochester, MN 55906, USA. Email
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Kaufman JM, Lapauw B, Mahmoud A, T'Sjoen G, Huhtaniemi IT. Aging and the Male Reproductive System. Endocr Rev 2019; 40:906-972. [PMID: 30888401 DOI: 10.1210/er.2018-00178] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 12/27/2018] [Indexed: 12/21/2022]
Abstract
This narrative review presents an overview of current knowledge on fertility and reproductive hormone changes in aging men, the factors driving and modulating these changes, their clinical consequences, and the benefits and risks of testosterone (T) therapy. Aging is accompanied by moderate decline of gamete quality and fertility. Population mean levels show a mild total T decline, an SHBG increase, a steeper free T decline, and a moderate LH increase with important contribution of comorbidities (e.g., obesity) to these changes. Sexual symptoms and lower hematocrit are associated with low T and are partly responsive to T therapy. The relationship of serum T with body composition and metabolic health is bidirectional; limited beneficial effects of T therapy on body composition have only marginal effects on metabolic health and physical function. Skeletal changes are associated primarily with estradiol and SHBG. Cognitive decline is not consistently linked to low T and is not improved by T therapy. Although limited evidence links moderate androgen decline with depressive symptoms, T therapy has small beneficial effects on mood, depressive symptoms, and vitality in elderly patients with low T. Suboptimal T (and/or DHT) has been associated with increased risk of stroke, but not of ischemic heart disease, whereas an association with mortality probably reflects that low T is a marker of poor health. Globally, neither severity of clinical consequences attributable to low T nor the nature and magnitude of beneficial treatment effects justify the concept of some broadly applied "T replacement therapy" in older men with low T. Moreover, long-term safety of T therapy is not established.
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Affiliation(s)
- Jean-Marc Kaufman
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Bruno Lapauw
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Ahmed Mahmoud
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Guy T'Sjoen
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Ilpo Tapani Huhtaniemi
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom.,Department of Physiology, Institute of Biomedicine, University of Turku, Turku, Finland
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Roelfsema F, Yang RJ, Liu PY, Takahashi PY, Veldhuis JD. Feedback on LH in Testosterone-Clamped Men Depends on the Mode of Testosterone Administration and Body Composition. J Endocr Soc 2018; 3:235-249. [PMID: 30623162 PMCID: PMC6320245 DOI: 10.1210/js.2018-00317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 11/20/2018] [Indexed: 11/19/2022] Open
Abstract
Context Quantitative studies of the short-term feedback of testosterone (T) on luteinizing hormone (LH) secretion in healthy men are relatively rare. Such studies require the shutting down of endogenous T secretion and the imposition of experimentally controlled IV T addback. Objective To evaluate whether pulsatile and continuous T delivery confers equivalent negative feedback on LH secretion. Design This was a placebo-controlled, blinded, and prospectively randomized crossover study comprising 16 healthy men [age range 23 to 54 years and a body mass index (BMI) between 22.3 and 34.2 kg/m2]. Subjects received ketoconazole to block endogenous T secretion and received continuous or 90-minute pulses of IV T addback. Setting The study was performed in a Clinical Translational Research Unit. Interventions Subjects underwent 14 hours of blood sampling at 10-minute intervals, with a bolus IV injection of 33 ng/kg gonadotropin-releasing hormone (GnRH). Main Outcome Measures Log-transformed LH and T concentration ratios before and after GnRH administration. Results Despite higher T concentrations during pulsatile T feedback, LH concentrations and secretion rates, whether driven by endogenous or exogenous GnRH, were similar to those during continuous T infusion, indicating diminished pulsatile T feedback. Feedback correlated negatively with BMI. Under controlled T feedback, basal but not pulsatile LH secretion correlated negatively with CT-estimated visceral fat mass. Conclusion Feedback by pulsatile T delivery has diminished inhibitory strength compared with continuous infusion. Feedback is negatively correlated with BMI.
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Affiliation(s)
- Ferdinand Roelfsema
- Department of Internal Medicine, Section Endocrinology and Metabolism, Leiden University Medical Center, Leiden, Netherlands
| | - Rebecca J Yang
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota
| | - Peter Y Liu
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota.,Division of Endocrinology, Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Harbor-University of California Los Angeles Medical Center, and Los Angeles Biomedical Research Institute, Los Angeles, California
| | - Paul Y Takahashi
- Department of Primary Care Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Johannes D Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota
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Serum variations of anti-mullerian hormone and total testosterone with aging in healthy adult Iranian men: A population-based study. PLoS One 2017; 12:e0179634. [PMID: 28715487 PMCID: PMC5513413 DOI: 10.1371/journal.pone.0179634] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/01/2017] [Indexed: 01/30/2023] Open
Abstract
Background Literature proves anti-mullerian hormone (AMH) and total testosterone (TT) as two important reproductive hormones in male development, however evidence regarding age variations of these hormones is lacking. Aims To estimate the normal serum AMH values and to assess the age-specific TT levels in men aged 30–70, we conducted the present population-based study. Methods A total of 831 healthy eligible men, aged 30–70 years, were recruited from Tehran Lipid and Glucose study cohort. Centiles for AMH were estimated according to the exponential normal 3-parameter model. The parametric method of Royston available in general software was applied for the first time to estimate the age-specific AMH and TT percentiles of 5th, 10th, 25th, 50th, 75th, 90th and 95th. Results Mean AMH level was 6.93, ranging from 0.1 to 40.1 ng/ml. Serum AMH concentrations followed a steady reduction with increasing age. Mean TT level was 4.8, ranging from 0.44 to 11.4 ng/ml. Discussion A measurable serum concentrations of AMH in healthy males throughout lifespan with variations, based on age, confirming a slight age-related AMH decline. Fractional polynomial (FP) regression models revealed that the mean and standard deviation (SD) of the TT were not associated with age, so the percentiles estimated were not age-specific. Conclusion We presented a nomogram of age-specific AMH values in a healthy cohort of Iranian men. This finding might have clinical importance in dealing hormonal disorders in men.
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Jaworski PED, Ramos A, Nicoleit AR, Bacarin LFDA, Olivo P. Importance of abdominal circumference and body mass index values in predicting male hypogonadism - A practical approach. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2017; 61:76-80. [PMID: 27598980 PMCID: PMC10522126 DOI: 10.1590/2359-3997000000203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 04/25/2016] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The objective of this study was to correlate the values of abdominal circumference (AC) and body mass index (BMI) with the levels of total testosterone (TT), free testosterone (FT) and sexual hormone binding globulin (SHBG). We aimed to analyze the association between the anthropometric values and variations in the hormonal levels. SUBJECTS AND METHODS A transversal prospective study was conducted. A total of 159 patients were included in the study. RESULTS BMI was inversely correlated with TT and SHBG (p = 0.02 and p = 0.006, respectively). AC was also inversely correlated withTT and SHBG (p = 0.006 and p < 0.0001, respectively). However, BMI did not correlate signicantly with these hormonal levels after adjusting for age. CONCLUSION This finding led to the conclusion that AC had a stronger inverse correlation than BMI with TT and SHBG. Our data suggested that AC alone can be used as an anthropometric parameter to help simplify the identification of men with low serum TT levels.
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Affiliation(s)
- Paulo Eduardo Dietrich Jaworski
- Departamento de UrologiaHospital Universitário Evangélico de CuritibaCuritibaPRBrasilDepartamento de Urologia, Hospital Universitário Evangélico de Curitiba, Curitiba, PR, Brasil
| | - Anderson Ramos
- Departamento de UrologiaHospital Universitário Evangélico de CuritibaCuritibaPRBrasilDepartamento de Urologia, Hospital Universitário Evangélico de Curitiba, Curitiba, PR, Brasil
| | - Arthur Radaelli Nicoleit
- Departamento de UrologiaHospital Universitário Evangélico de CuritibaCuritibaPRBrasilDepartamento de Urologia, Hospital Universitário Evangélico de Curitiba, Curitiba, PR, Brasil
| | - Luis Fernando de Almeida Bacarin
- Faculdade de MedicinaFaculdade Evangélica do ParanáCuritibaPRBrasilFaculdade de Medicina, Faculdade Evangélica do Paraná (Fepar), Curitiba, PR, Brasil
| | - Pedro Olivo
- Faculdade de MedicinaFaculdade Evangélica do ParanáCuritibaPRBrasilFaculdade de Medicina, Faculdade Evangélica do Paraná (Fepar), Curitiba, PR, Brasil
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Hypogonadism in patients with chronic obstructive pulmonary disease: relationship with airflow limitation, muscle weakness and systemic inflammation. ALEXANDRIA JOURNAL OF MEDICINE 2016. [DOI: 10.1016/j.ajme.2015.01.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Kuhn JM. Hypoandrogénie de l’homme âgé : quels critères ? Quels mécanismes ? Qui traiter ? Presse Med 2014; 43:178-9. [DOI: 10.1016/j.lpm.2013.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Moskovic DJ, Katz DJ, Akhavan A, Park K, Mulhall JP. Clomiphene citrate is safe and effective for long-term management of hypogonadism. BJU Int 2012; 110:1524-8. [PMID: 22458540 DOI: 10.1111/j.1464-410x.2012.10968.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To assess the efficacy and safety of long-term clomiphene citrate (CC) therapy in symptomatic patients with hypogonadism (HG). PATIENTS AND METHODS Serum T, oestradiol and luteinizing hormone (LH) were measured in patients who were treated with CC for over 12 months. Additionally, bone densitometry (BD) results were collected for all patients. Demographic, comorbidity, treatment and Androgen Deficiency in Aging Men (ADAM) score data were also recorded. Comparison was made between baseline and post-treatment variables, and multivariable analysis was conducted to define predictors of successful response to CC. The main outcome measures were predictors of response and long-term results with long-term CC therapy in hypogonadal patients. RESULTS The 46 patients (mean age 44 years) had baseline serum testosterone (T) levels of 228 ng/dL. Follow-up T levels were 612 ng/dL at 1 year, 562 ng/dL at 2 years, and 582 ng/dL at 3 years (P < 0.001). Mean femoral neck and lumbar spine BD scores improved significantly. ADAM scores (and responses) fell from a baseline of 7 to a nadir of 3 after 1 year. No adverse events were reported by any patients. CONCLUSIONS Clomiphene citrate is an effective long-term therapy for HG in appropriate patients. The drug raises T levels substantially in addition to improving other manifestations of HG such as osteopenia/osteoporosis and ADAM symptoms.
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Affiliation(s)
- Daniel J Moskovic
- Sexual & Reproductive Medicine Program, Urology Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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Keenan DM, Clarke IJ, Veldhuis JD. Noninvasive analytical estimation of endogenous GnRH drive: analysis using graded competitive GnRH-receptor antagonism and a calibrating pulse of exogenous GnRH. Endocrinology 2011; 152:4882-93. [PMID: 22028450 PMCID: PMC3230048 DOI: 10.1210/en.2011-1461] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Homeostatic control of endocrine systems proceeds via feedforward (agonistic, stimulatory) and feedback (antagonistic, inhibitory) interactions mediated via implicit dose-response functions. However, neither the feedback/feedforward pathways nor the dose-response interfaces are directly observed in vivo. Thus, the goal was to formulate and estimate an ensemble construct of time-varying feedback/feedforward interactions among GnRH, LH, and testosterone (T) in the male gonadal axis. The new analytical model revises and extends an earlier construct by: 1) allowing systemic T concentrations to inhibit hypothalamic GnRH output; 2) estimating GnRH outflow after injection of a calibrating pulse of biosynthetic GnRH; 3) framing the pituitary response to GnRH as a secretory burst, rather than continuous LH release; and 4) regressing feedback and feedforward ensemble parameters on age, rather than evaluating age dichotomously. Application of this methodology in 21 men aged 23-72 yr unveiled age-related 1) diminution of GnRH efficacy normalized for the decline in free T with age (P = 0.016), 2) potentiation of maximal T feedback onto (inhibition of) GnRH secretion (P = 0.006), and 3) accentuation of hypothalamic GnRH's sensitivity to T repression (P = 0.003). Outcomes were specific, because injected GnRH agonist and antagonist concentrations were invariant of age. We conclude that combining experimental and analytical strategies may provide a noninvasive means to investigate and decipher feedback determinants of unobserved endocrine signal(s).
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Affiliation(s)
- Daniel M Keenan
- Department of Statistics, University of Virginia, Charlottesville, Virginia 22904, USA
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Ten Kulve JS, de Jong FH, de Ronde W. The effect of circulating estradiol concentrations on gonadotropin secretion in young and old castrated male-to-female transsexuals. Aging Male 2011; 14:155-61. [PMID: 20828248 DOI: 10.3109/13685538.2010.511328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
CONTEXT In aging men, circulating testosterone (T) declines which is associated with an increase in the levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) , albeit insufficient to maintain T at its original level. It has been speculated that a higher sensitivity of the hypothalamus and/or pituitary for the feedback effect of circulating sex hormones in older men is responsible. OBJECTIVE To compare the effect of experimentally varied plasma levels of estradiol on the LH and FSH secretion in young and old castrated male-to-female transsexuals, in almost absence of T. DESIGN, SUBJECTS, AND INTERVENTIONS: In 10 healthy, young (mean age 37.6 ± 6.2 years) and 11 healthy, old (mean age 68.1 ± 7.0) male-to-female transsexuals after gonadectomy plasma estradiol levels were experimentally varied with estradiol patches (the first week 100 μg/day patches, the second week 50 μg/day, the third week 25 μg/day and the fourth week no patch was applied) and plasma levels of LH and FSH were monitored after every week. RESULTS Mean plasma bioavailable estradiol (E2) levels in the two groups ranged between 13.6 and 104 pmol/l. LH and FSH were inversely related to peripheral estradiol levels, were lower in the old group at all time points reaching statistical significance in the last week of the study when no patch was applied and estradiol levels were extremely low. CONCLUSIONS The results of this study do not support the hypothesis of an age related increasing sensitivity of the hypothalamo-pituitary compartment for the negative feedback of E2, but suggest a deficient feed-forward drive in older male-to-female transsexuals.
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Affiliation(s)
- Jennifer S Ten Kulve
- Department of Endocrinology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands
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The influence of age on bioavailable and free testosterone is independent of body mass index and glucose levels. World J Urol 2011; 29:541-6. [PMID: 21739121 DOI: 10.1007/s00345-011-0724-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 06/22/2011] [Indexed: 10/18/2022] Open
Abstract
PURPOSE To evaluate the influence of age on serum levels of total testosterone (TT), bioavailable testosterone (BT), free testosterone (FT), and sex-hormone binding globulin (SHBG), considering the presence of fasting blood glucose levels and body mass index (BMI) in a selected male population. METHODS A total of 428 men were analyzed. Anthropometry was taken from all, considering BMI as general obesity indicative variable. Fasting blood samples were drawn for determination of plasma glucose levels and serum levels of albumin, TT, and SHBG. The values of BT and FT were calculated from TT, SHBG, and albumin, by Vermeulen's equation. Statistical significance was set at P ≤ 0.05. RESULTS Age was negatively correlated to BT (r = -0.301; P < 0.001) and FT (r = -0.273; P < 0.001), but not to TT levels (r = 0.002, P = 0.974). Age was positively correlated to SHBG (r = 0.376; P < 0.001). Age was independently associated with the occurrence of high SHBG levels (OR = 1.07, 95%CI = 1.05-1.10, P < 0.001) and of low BT (OR = 1.04, 95%CI = 1.02-1.07, P < 0.001) and FT levels (OR = 1.05, 95%CI = 1.03-1.08, P < 0.001), but not with low levels of TT (P = 0.08). CONCLUSIONS Age was significantly associated to high levels of SHBG and to low levels of BT and FT, without significant association to TT. This pattern was independent of BMI and glucose levels.
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Iranmanesh A, Mulligan T, Veldhuis JD. Age in men does not determine gonadotropin-releasing hormone's dose-dependent stimulation of luteinizing hormone secretion under an exogenous testosterone clamp. J Clin Endocrinol Metab 2010; 95:2877-84. [PMID: 20357176 PMCID: PMC2902075 DOI: 10.1210/jc.2009-2581] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Aging is associated with a decline in incremental LH pulse amplitude, which could be due to decreased GnRH secretion or impaired GnRH action. HYPOTHESIS Inconsistent published studies of GnRH action in older men may be due to disparate sex-steroid milieus. FACILITY This study was conducted at a clinical translational-research unit. SUBJECTS We studied 16 healthy men (8 young men and 8 older men). METHODS An overnight transdermal testosterone (T) clamp was implemented before randomly ordered injections of 0, 2.5, 10, 25, 250, and 750 ng GnRH on separate days (96 study sessions). OUTCOMES LH responses were quantified by variable-waveform deconvolution analysis. RESULTS The T clamp maintained age-invariant mean concentrations of total, bioavailable, and free T, SHBG, LH, FSH, and prolactin. By two-way analysis of covariance, GnRH dose (P < 0.001) but not age (0.15 < or = P < or = 0.83) determined mean, peak, incremental, and pulsatile LH responses. Statistical power (median) was 95, 98, 90, and 99% to detect a 30% or greater age contrast at P < or = 0.05 in mean, peak, incremental, and pulsatile LH responses, and greater than 99% to detect a 30% or greater age contrast in bioavailable or total T concentrations. Higher GnRH doses (P < 0.001) abbreviated LH secretory bursts in both age groups. CONCLUSION In the face of eugonadal concentrations of total, bioavailable, and free T, young and older men exhibit remarkably similar LH responses to a 300-fold dose range of exogenous GnRH. Accordingly, previously reported disparate effects of age on GnRH action may reflect in part age-discrepant sex-steroid milieus.
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Affiliation(s)
- Ali Iranmanesh
- Endocrine Section, Department of Medicine, Salem Veterans Affairs Medical Center, Salem, Virginia 24153, USA
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Luna M, Finkler E, Barritt J, Bar-Chama N, Sandler B, Copperman AB, Grunfeld L. Paternal age and assisted reproductive technology outcome in ovum recipients. Fertil Steril 2009; 92:1772-5. [DOI: 10.1016/j.fertnstert.2009.05.036] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 05/13/2009] [Accepted: 05/13/2009] [Indexed: 11/25/2022]
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Liu PY, Takahashi PY, Roebuck PD, Bailey JN, Keenan DM, Veldhuis JD. Testosterone's short-term positive effect on luteinizing-hormone secretory-burst mass and its negative effect on secretory-burst frequency are attenuated in middle-aged men. J Clin Endocrinol Metab 2009; 94:3978-86. [PMID: 19584190 PMCID: PMC2758726 DOI: 10.1210/jc.2009-0135] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Testosterone (T) production declines and LH pulses become smaller and more frequent in middle-aged men. The mechanisms underlying these changes are not known. RATIONALE Small frequent LH pulses in middle-aged men could reflect impaired feedback by systemic T. HYPOTHESIS Middle age disrupts negative feedback by T on selected facets of LH secretion. SUBJECTS AND SETTING Healthy men were studied at an academic medical center. METHODS The protocol comprised blockade of gonadal steroidogenesis and graded transdermal addback of T doses of 0, 2.5, 5, or 7.5 mg/d designed to span the castrate to physiological range of T concentrations in each of 23 healthy men ages 19-71 yr (interquartile range, 28-53 yr). We quantified 12-h basal and pulsatile LH secretion (92 time series) using a mathematically justified deconvolution method. RESULTS Stepwise T supplementation from the hypogonadal through the eugonadal range repressed mean (12-h) LH concentrations (P = 0.001). By regression analysis, age attenuated the capabilities of increasing T concentrations to 1) increase LH secretory-burst mass (P < 0.0001); and 2) decrease LH secretory-burst frequency (P = 0.025). Age did not alter T's feedback on basal LH secretion, interpulse regularity, the waveform of LH secretory bursts, or the slow half-life of LH. CONCLUSION Middle age impairs both the positive and negative actions of systemic T on pulsatile LH secretion in healthy men, thus potentially explaining earlier inconsistencies in feedback studies based upon single-sample mean LH concentrations. Longitudinal studies will be required to elucidate the precise age dependence of inferred dual feedback failure.
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Affiliation(s)
- Peter Y Liu
- Endocrine Research Unit, Mayo Medical School, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
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Jaspersen-Gastelum J, Rodríguez JA, Espinosa de los Monteros FJ, Beas-Sandoval L, Guzmán-Esquivel J, Calvo DD, Gutiérrez T. Prostatic profile, premature ejaculation, erectile function and andropause in an at-risk Mexican population. Int Urol Nephrol 2008; 41:303-12. [DOI: 10.1007/s11255-008-9417-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2008] [Accepted: 06/09/2008] [Indexed: 11/30/2022]
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Frattarelli JL, Miller KA, Miller BT, Elkind-Hirsch K, Scott RT. Male age negatively impacts embryo development and reproductive outcome in donor oocyte assisted reproductive technology cycles. Fertil Steril 2008; 90:97-103. [PMID: 17765235 DOI: 10.1016/j.fertnstert.2007.06.009] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 05/10/2007] [Accepted: 06/05/2007] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine whether male age influences embryo development and reproductive potential in assisted reproductive technology cycles. DESIGN Retrospective cohort analysis. SETTING Private IVF center. PATIENT(S) One thousand twenty-three male partners participating in anonymous oocyte donation cycles. INTERVENTION(S) Infertile couples undergoing 1,023 anonymous oocyte donation cycles. MAIN OUTCOME MEASURE(S) Live birth rate. RESULT(S) A significant increase in pregnancy loss, decrease in live birth rate, and decrease in blastocyst formation rate were noted in men >50 years of age. There was no significant difference in implantation rate, pregnancy rate, or early embryo development through the cleavage stage (demonstrated by fertilization rate, embryo cleavage rate, percentage of nonfertilized or polyspermic embryos, rate of embryo arrest, or seven or more cell embryo development on day 3). Men < or =45 years of age had significantly more semen volume and more motile sperm than men >45 years of age. There was no significant change in sperm morphology or concentration. CONCLUSION(S) After controlling for female age with use of the donor oocyte model, male age >50 years significantly affected pregnancy outcomes and blastocyst formation rates. Semen volume and total motility decreased with increasing male age. Initial embryo morphology through the cleavage stage was not affected.
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Affiliation(s)
- John L Frattarelli
- Reproductive Medicine Associates of New Jersey, Morristown, New Jersey 08873, USA.
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18
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Becerra Fernández A, Enríquez Acosta L. Documento básico de consenso sobre el síndrome de hipogonadismo de inicio tardío. ACTA ACUST UNITED AC 2008; 55:5-28. [DOI: 10.1016/s1575-0922(08)70632-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Accepted: 10/15/2007] [Indexed: 12/25/2022]
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Böttner M, Leonhardt S, Wuttke W, Jarry H. Changes of expression of genes related to the activity of the gonadotrophin-releasing hormone pulse generator in young versus middle-aged male rats. J Neuroendocrinol 2007; 19:779-87. [PMID: 17850460 DOI: 10.1111/j.1365-2826.2007.01589.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In females, it is well established that changes in the expression of neurotransmitters and peptides regulating the activity of the gonadotrophin-releasing hormone (GnRH) pulse generator are altered during ageing. By contrast, little is known about whether those age-related changes also occur in males. Therefore, we designed an animal study with orchidectomised young and middle-aged male rats to investigate changes in luteinising hormone (LH) secretion profiles and changes in the mRNA expression of genes regulating the activity of the GnRH pulse generator. Our results demonstrate that middle-aged rats exhibit lower serum LH levels and relatively fewer LH pulses with attenuated amplitude compared to young animals. Furthermore, upon ageing, GnRH mRNA expression is up-regulated in the preoptic area and the septum where GnRH neurones reside. Analysis of mRNA levels of glutamate decarboxylase (GAD) enzymes revealed that GAD(65) and GAD(67) mRNA expression increased in the mediobasal hypothalamus (MBH) and that GAD(67) mRNA levels decreased in the suprachiasmatic nucleus. In addition, we observed an age-related increase of oestrogen receptor (ER)alpha mRNA in the MBH, and both ERalpha and ERbeta mRNA expression was up-regulated in the pituitary of middle-aged rats compared to young animals. Taken together, our data support the existence of a male 'andropause' that is, like the menopause in females, accompanied by changes in neurotransmitter and hormone receptor expression that are involved in regulating the function of the GnRH pulse generator.
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Affiliation(s)
- M Böttner
- Department of Anatomy, University of Kiel, Kiel, Germany.
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20
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Esquifino AI, Cano P, Jiménez-Ortega V, Fernández-Mateos P, Cardinali DP. Neuroendocrine-immune correlates of circadian physiology: studies in experimental models of arthritis, ethanol feeding, aging, social isolation, and calorie restriction. Endocrine 2007; 32:1-19. [PMID: 17992597 DOI: 10.1007/s12020-007-9009-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 09/11/2007] [Accepted: 09/11/2007] [Indexed: 10/22/2022]
Abstract
Virtually all neuroendocrine and immunological variables investigated in animals and humans display biological periodicity. Circadian rhythmicity is revealed for every hormone in circulation as well as for circulating immune cells, lymphocyte metabolism and transformability, cytokines, receptors, and adhesion molecules. Clock genes, notably the three Period (Per1/Per2/Per3) genes and two Cryptochrome (Cry1/Cry2) genes, are present in immune and endocrine cells and are expressed in a circadian manner in human cells. This review discusses the circadian disruption of hormone release and immune-related mechanisms in several animal models in which circulating cytokines are modified including rat adjuvant arthritis, social isolation in rats and rabbits and alcoholism, the aging process and calorie restriction in rats. In every case the experimental manipulation used perturbed the temporal organization by affecting the shape and amplitude of a rhythm or by modifying the intrinsic oscillatory mechanism itself.
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Affiliation(s)
- Ana I Esquifino
- Departamento de Bioquimica y Biologia Molecular III, Facultad de Medicina, Universidad Complutense, 28040, Madrid, Spain.
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21
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Liu PY, Takahashi PY, Roebuck PD, Veldhuis JD. Age or factors associated with aging attenuate testosterone's concentration-dependent enhancement of the regularity of luteinizing hormone secretion in healthy men. J Clin Endocrinol Metab 2006; 91:4077-84. [PMID: 16868060 DOI: 10.1210/jc.2005-2811] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Healthy older men have reduced testosterone (Te) production and frequent, small irregular LH pulses. Which is cause and which is effect are not known. RATIONALE In model systems, frequent and irregular LH pulses reflect attenuated feedback inhibition by Te. HYPOTHESIS Factors associated with aging impair negative feedback by Te. SUBJECTS AND SETTING Healthy men at an academic medical center were studied. METHODS The study used quantification of the regularity of LH release patterns during blockade of gonadal steroidogenesis and graded transdermal Te addback in 18 healthy men aged 18-65 yr. RESULTS In the cohort as a whole, stepwise Te repletion repressed LH concentrations (P = 0.001) and enhanced the quantifiable orderliness of LH release patterns (P < 0.001). By regression analysis, age attenuated the capability of increasing Te concentrations to regularize LH secretion patterns (P = 0.019). However, after a fixed GnRH stimulus, the effect of Te on LH regularity was invariant of the age factor (P = 0.16), thus pointing to a hypothalamic locus of impaired Te feedback. SUMMARY Aging disrupts the capability of systemic Te concentrations to maintain orderly LH secretion under endogenous, but not exogenous, GnRH drive. CONCLUSIONS Age or factors associated with increased age reduce negative feedback by any given total Te concentration on hypothalamopituitary GnRH-LH outflow, thus contributing to disorderly LH secretion.
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Affiliation(s)
- Peter Y Liu
- Endocrine Research Unit, Mayo Clinic School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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22
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Keenan DM, Takahashi PY, Liu PY, Roebuck PD, Nehra AX, Iranmanesh A, Veldhuis JD. An ensemble model of the male gonadal axis: illustrative application in aging men. Endocrinology 2006; 147:2817-28. [PMID: 16513832 DOI: 10.1210/en.2005-1356] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Testosterone (Te) production declines in the aging male, albeit for unknown reasons. Plausible mechanisms include reduced secretion of GnRH, less feedforward by LH, and/or altered feedback by systemic Te. The present study tests all three postulates in a cohort of 10 young (20-35 yr old) and eight older (50-72 yr old) men. The experimental paradigm comprised graded blockade of the GnRH receptor to create four distinct strata of LH and Te pulsatility in each subject. A novel analytical formalism was developed to reconstruct implicit dose-response functions linking 1) virtual GnRH outflow positively to LH secretion, 2) LH pulses positively to Te secretion, and 3) Te concentrations negatively to the size and number of LH secretory bursts. Validation was by direct pituitary sampling in the horse and sheep. Statistical comparisons disclosed that age decreased the efficacy of each of 1) virtual GnRH outflow (P < 0.01), 2) LH drive of Te secretion (P < 0.01), and 3) total, bioavailable and free Te feedback on GnRH-driven LH secretion (P = 0.015). In contrast, age increased the potency of virtual GnRH feedforward (P = 0.013) and did not affect Te's inhibition of LH pulse frequency. Unexplained variance was less than 10%. Robustness was shown by resampling techniques. Accordingly, competitive silencing of one locus of control and ensemble-based analyses identified triple regulatory deficits in the aging male gonadal axis. The generality of the present integrative model suggests utility in parsing interlinked adaptations in other physiological networks.
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Affiliation(s)
- Daniel M Keenan
- Department of Statistics, University of Virginia, Charlottesville, Virginia 22903, USA
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Abstract
There are several problems facing aging men, especially sexual dysfunction, hypogonadism, and psychologic changes. This constellation of changes is sometimes referred to as "manopause" or "andropause." Unlike the dramatic changes in the hormonal milieu occurring during menopause in women, the age-related changes in reproductive hormones of men are subtle and occur gradually throughout the years of mature life. It has been estimated that circulating testosterone (T) declines longitudinally from age 19 at an average rate of 1% per year. The free or dialyzable fraction of serum T and the bioavailable (the sum of free fraction and loosely bound to albumin fraction) T decline more rapidly with age. Although the essential role of androgens in reproductive tissue development and emergence of secondary sex characteristics is well known, their role in adult sexual function seems to be primarily facultative. The effect of T on the central nervous system extends beyond sexual behavior. T has been shown to alter mood, memory, ability to concentrate, and the overall sense of vigor and well being that may interact with a host of other psychologic changes associated with aging. Disordered erectile function is not generally an endocrine problem but rather vascular, neurologic, and psychogenic in origin. It also may be the first sign of systemic vascular disease. The clinical management of andropause requires an individualized approach. In some men, the main problem may be psychologic, whereas in others, hypogonadism may play an important role. Many with erectile failure, suffer silently regardless of its etiology. In this review, we suggest some practical guidelines for the management of these conditions.
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Affiliation(s)
- Arshag D Mooradian
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Saint Louis University, St Louis, MO 63104, USA.
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24
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Liu PY, Iranmanesh A, Nehra AX, Keenan DM, Veldhuis JD. Mechanisms of hypoandrogenemia in healthy aging men. Endocrinol Metab Clin North Am 2005; 34:935-55, ix. [PMID: 16310632 DOI: 10.1016/j.ecl.2005.07.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Peter Y Liu
- Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Education, General Clinical Research Center, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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25
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De Cuypere G, T'Sjoen G, Beerten R, Selvaggi G, De Sutter P, Hoebeke P, Monstrey S, Vansteenwegen A, Rubens R. Sexual and physical health after sex reassignment surgery. ARCHIVES OF SEXUAL BEHAVIOR 2005; 34:679-90. [PMID: 16362252 DOI: 10.1007/s10508-005-7926-5] [Citation(s) in RCA: 186] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Revised: 09/02/2004] [Accepted: 12/02/2004] [Indexed: 05/05/2023]
Abstract
A long-term follow-up study of 55 transsexual patients (32 male-to-female and 23 female-to-male) post-sex reassignment surgery (SRS) was carried out to evaluate sexual and general health outcome. Relatively few and minor morbidities were observed in our group of patients, and they were mostly reversible with appropriate treatment. A trend toward more general health problems in male-to-females was seen, possibly explained by older age and smoking habits. Although all male-to-females, treated with estrogens continuously, had total testosterone levels within the normal female range because of estrogen effects on sex hormone binding globulin, only 32.1% reached normal free testosterone levels. After SRS, the transsexual person's expectations were met at an emotional and social level, but less so at the physical and sexual level even though a large number of transsexuals (80%) reported improvement of their sexuality. The female-to-males masturbated significantly more frequently than the male-to-females, and a trend to more sexual satisfaction, more sexual excitement, and more easily reaching orgasm was seen in the female-to-male group. The majority of participants reported a change in orgasmic feeling, toward more powerful and shorter for female-to-males and more intense, smoother, and longer in male-to-females. Over two-thirds of male-to-females reported the secretion of a vaginal fluid during sexual excitation, originating from the Cowper's glands, left in place during surgery. In female-to-males with erection prosthesis, sexual expectations were more realized (compared to those without), but pain during intercourse was more often reported.
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Affiliation(s)
- Griet De Cuypere
- Department of Sexology and Gender Problems, University Hospital Ghent, Ghent, Belgium.
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26
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Kaufman JM, Vermeulen A. The decline of androgen levels in elderly men and its clinical and therapeutic implications. Endocr Rev 2005; 26:833-76. [PMID: 15901667 DOI: 10.1210/er.2004-0013] [Citation(s) in RCA: 698] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Aging in men is accompanied by a progressive, but individually variable decline of serum testosterone production, more than 20% of healthy men over 60 yr of age presenting with serum levels below the range for young men. Albeit the clinical picture of aging in men is reminiscent of that of hypogonadism in young men and decreased testosterone production appears to play a role in part of these clinical changes in at least some elderly men, the clinical relevancy of the age-related decline in sex steroid levels in men has not been unequivocally established. In fact, minimal androgen requirements for elderly men remain poorly defined and are likely to vary between individuals. Consequently, borderline androgen deficiency cannot be reliably diagnosed in the elderly, and strict differentiation between "substitutive" and "pharmacological" androgen administration is not possible. To date, only a few hundred elderly men have received androgen therapy in the setting of a randomized, controlled study, and many of these men were not androgen deficient. Most consistent effects of treatment have been on body composition, but to date there is no evidence-based documentation of clinical benefits of androgen administration to elderly men with normal or moderately low serum testosterone in terms of diminished morbidity or of improved survival or quality of life. Until the long-term risk-benefit ratio for androgen administration to elderly is established in adequately powered trials of longer duration, androgen administration to elderly men should be reserved for the minority of elderly men who have both clear clinical symptoms of hypogonadism and frankly low serum testosterone levels.
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Affiliation(s)
- Jean M Kaufman
- Department of Endocrinology, Ghent University Hospital, Ghent B-9000, Belgium.
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27
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Van Vliet M, Spruit MA, Verleden G, Kasran A, Van Herck E, Pitta F, Bouillon R, Decramer M. Hypogonadism, quadriceps weakness, and exercise intolerance in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2005; 172:1105-11. [PMID: 16100014 DOI: 10.1164/rccm.200501-114oc] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Circulating levels of testosterone and gonadotrophins of patients with chronic obstructive pulmonary disease (COPD) have never been compared with those of elderly men with normal pulmonary function. Moreover, the relationship of hypogonadism with quadriceps muscle weakness and exercise intolerance has been studied scarcely in men with COPD. OBJECTIVES To compare circulating levels of hormones of the pituitary-gonadotrophic axis of men with COPD with those of age-matched control subjects. Moreover, to study the relationship of hypogonadism with quadriceps muscle force, 6-min walking distance, and systemic markers of inflammation in the patients. METHODS AND MEASUREMENTS Circulating levels of follicle-stimulating hormone, luteinizing hormone, testosterone, and sex hormone-binding globulin were determined, and free testosterone was calculated in 78 patients (FEV1: 44 +/- 17% of the predicted values) and 21 control subjects. Moreover, quadriceps muscle force, 6-min walking distance, number of pack-yr, and systemic inflammation were determined. MAIN RESULTS Follicle-stimulating hormone and luteinizing hormone were higher in the patients, whereas testosterone was lower (p < or = 0.05). The latter finding was also present in 48 non-steroid-using patients with normal blood gases. Low androgen status was significantly related to quadriceps muscle weakness (r = 0.48) and C-reactive protein (r = -0.39) in the patients, but not to exercise intolerance, the number of pack-yr, or increased circulating levels of interleukin 8 or soluble receptors of tumor necrosis factor alpha. CONCLUSIONS In contrast to exercise intolerance, quadriceps muscle weakness is related to low circulating levels of testosterone in men with COPD.
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Affiliation(s)
- Monique Van Vliet
- Respiratory Rehabilitation, University Hospital Gasthuisberg, Herestraat 49, B-3000, Leuven, Belgium
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28
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de Ronde W, van der Schouw YT, Pierik FH, Pols HAP, Muller M, Grobbee DE, Gooren LJG, Weber RFA, de Jong FH. Serum levels of sex hormone-binding globulin (SHBG) are not associated with lower levels of non-SHBG-bound testosterone in male newborns and healthy adult men. Clin Endocrinol (Oxf) 2005; 62:498-503. [PMID: 15807883 DOI: 10.1111/j.1365-2265.2005.02252.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE It is generally accepted that SHBG decreases the bioavailability and activity of testosterone (T). In in vitro experiments increased levels of SHBG will be associated with decreased levels of non-SHBG bound testosterone (non-SHBG-T). However, in vivo SHBG can alter both production and clearance rates and thus plasma levels of T. DESIGN AND PATIENTS In order to study the effect of SHBG on the levels of non-SHBG-T in vivo in the presence of an active hypothalamo-pituitary-gonadal (HPG) axis we conducted a cross sectional study in 400 healthy adult men with an age range of 40-80 years and in 106 newborn boys. MEASUREMENTS In both groups, regression coefficients (beta) and partial correlation coefficients (r) were calculated for the relationship between SHBG and T or non-SHBG-T. Adult men were divided into age groups per decade (40-50 years, 51-60 years, 61-70 years and 71-80 years) to study possible differences in the impact of SHBG on the level of non-SHBG-T throughout ageing. RESULTS Higher levels of SHBG were associated with higher levels of total testosterone in neonates (beta = 0.02 +/- 0.004, r = 0.44, P < 0.001) but not with non-SHBG-T (beta = -0.001 +/- 0.001, r = 0.05, P = 0.52). In adult men there was a significant age related increase in levels of SHBG and an age-related decrease of both total and non-SHBG-T. Higher SHBG was strongly associated with higher total testosterone in all age groups (beta = 0.26, 0.26, 0.26 and 0.23 for 40-50 years, 51-60 years, 61-70 years and 71-80 years, respectively, P < 0.001 for all age groups). Higher SHBG was not or only slightly associated with higher non-SHBG-T beta = 0.02 (P = 0.32), beta = 0.04 (P = 0.03), beta = 0.04 (P = 0.02) and beta = 0.02 (P = 0.16) for 40-50 years, 51-60 years, 61-70 years and 71-80 years, respectively. CONCLUSIONS In contrast to general belief, SHBG levels barely influence levels of non-SHBG-bound testosterone both in male newborns and healthy adult men: the influence, if any, is positive. Consequently the age related increase of SHBG does not account for the age related decline in non-SHBG-T in healthy adult men.
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Affiliation(s)
- Willem de Ronde
- Department of Internal Medicine, Erasmus Medical Center, 3000 DR Rotterdam, the Netherlands
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Abstract
The number of men in the United States > or =65 years of age is projected to increase from 14,452,000 in 2000 to 31,343,000 in 2030. Approximately 30% of men 60-70 years of age and 70% of men 70-80 years of age have low bioavailable or free testosterone levels. Symptoms and findings of testosterone deficiency are similar to those associated with aging. They include loss of energy, depressed mood, decreased libido, erectile dysfunction, decreased muscle mass and strength, increased fat mass, frailty, osteopenia, and osteoporosis. Several small clinical trials indicate that testosterone replacement therapy can improve many of these findings; however, the studies have not been powered to assess potential risks, such as the need for invasive treatment of benign prostatic hyperplasia, development of a clinical prostate cancer, or cardiovascular events. Thus, the benefit/risk ratio of testosterone replacement therapy in aging men is not known.
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Affiliation(s)
- Rabih A Hijazi
- Department of Medicine, Baylor College of Medicine, VA Medical Center, Houston, Texas, USA.
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30
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Veldhuis JD, Iranmanesh A, Mulligan T. Age and testosterone feedback jointly control the dose-dependent actions of gonadotropin-releasing hormone in healthy men. J Clin Endocrinol Metab 2005; 90:302-9. [PMID: 15494457 PMCID: PMC1201433 DOI: 10.1210/jc.2004-1313] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Healthy older men manifest combined declines in testosterone concentrations, LH secretory burst mass (amount of LH released per pulse), and feedback-sensitive regularity of unknown cause. To test a unifying hypothesis of simultaneous reductions in GnRH outflow, gonadotrope responsiveness to GnRH, and androgenic negative feedback, we monitored LH secretion 1) after bolus iv injection of a 1000-fold range of randomly ordered individual doses of GnRH on separate mornings, 2) during unmodified (eugonadal) or testosterone-withdrawn (hypoandrogenemic) negative feedback, and 3) in 16 young (age, 18-35 yr) and 15 older (age, 60-85 yr) healthy men. LH secretory burst mass and pattern regularity were quantitated by intensive blood sampling, high specificity LH beta-subunit-directed immunoradiometric assay, deconvolution analysis, and approximate entropy. GnRH dose responsiveness was assessed by four-parameter nonlinear regression analysis. We demonstrated that older men exhibit 1) delayed attainment of GnRH-evoked maximal LH secretion; 2) enhanced potency of GnRH stimulation in both the feedback-intact and feedback-withdrawn states; 3) elevated gonadotrope sensitivity to GnRH, unmasked by experimental testosterone depletion; 4) comparable young adult-like GnRH efficacy, independent of testosterone feedback milieu; and 5) diminished regularity of GnRH-induced LH release evident only during unmodified androgenic feedback. We conclude that a 3-fold interaction among GnRH dose, testosterone concentration, and age governs GnRH action, and age determines both testosterone-modulated and testosterone-independent actions of GnRH.
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Affiliation(s)
- Johannes D Veldhuis
- Division of Endocrinology and Metabolism, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA.
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31
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Veldhuis JD, Iranmanesh A. Short-term aromatase-enzyme blockade unmasks impaired feedback adaptations in luteinizing hormone and testosterone secretion in older men. J Clin Endocrinol Metab 2005; 90:211-8. [PMID: 15483079 PMCID: PMC1315304 DOI: 10.1210/jc.2004-0834] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The mechanisms subserving hypoandrogenemia and relative hypogonadotropism in older men are not known. The present study tests the clinical hypothesis that aging impairs hypothalamopituitary adaptations to feedback withdrawal induced by antagonism of estrogen biosynthesis. To this end, we appraised gonadal axis responses to estrogen depletion induced by anastrozole (a potent and selective aromatase inhibitor) in nine older and 11 young men vs. placebo in 17 other older and eight young men. The study design comprised a prospectively randomized, double-blind, parallel-cohort intervention. To monitor LH release, blood was sampled every 10 min for 24 h; LH concentrations were assayed by two-site monoclonal immunoradiometric assay; pulsatile LH release quantitated by a model-free discrete peak-detection technique (Cluster); feedback-dependent orderliness of LH secretion via the approximate entropy statistic; and 24-h rhythmicity of LH concentrations by cosine analysis. At baseline, older men had comparable estradiol and testosterone but lower LH concentrations than young controls. Exposure to anastrozole reduced (24-h pooled) serum estradiol concentrations by 50% (P < 0.001) and elevated mean LH concentrations by 2.1-fold (P < 0.001) in both the young and older cohorts. However, older men failed to achieve young adult augmentation of the following: 1) total testosterone concentrations (P < 0.01) or molar testosterone to SHBG ratios (P < 0.01); 2) incremental LH pulse amplitude (P < 0.001) and LH peak area (P < 0.01); 3) mean LH pulse frequency (P = 0.0044); and 4) quantifiable irregularity (approximate entropy) of LH release patterns (P < 0.001). FSH concentrations became comparable in the two age cohorts. In summary, administration of a potent and selective aromatase antagonist reduces estradiol and elevates mean LH concentrations equivalently in young and older men. The low estrogen-feedback state in elderly men unmasks diminished incremental LH pulse amplitude and area; absence of further acceleration of LH pulse frequency; impaired regulation of the orderliness of LH release; and reduced testosterone to SHBG ratios. Thus, aging alters expected hypothalamopituitary-gonadal adaptations to short-term partial estrogen depletion in healthy men.
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Affiliation(s)
- Johannes D Veldhuis
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA.
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Svartberg J, von Mühlen D, Sundsfjord J, Jorde R. Waist circumference and testosterone levels in community dwelling men. The Tromsø study. Eur J Epidemiol 2004; 19:657-63. [PMID: 15461197 DOI: 10.1023/b:ejep.0000036809.30558.8f] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
To examine the relationship of total and free testosterone and sex hormone-binding globulin (SHBG) with central obesity in men, we studied 1548 men aged 25-84 years that took part in the 1994--1995 survey of the Tromsø study. Total testosterone and SHBG were measured by immuno-assay and the free testosterone fraction was calculated. These measurements were analyzed in relation to anthropometric data and lifestyle factors. The age-adjusted correlation between waist circumference (WC) and total testosterone was -0.34 (p < 0.001), between WC and free testosterone -0.09 (p < 0.001) and, between WC and SHBG -0.44 (p < 0.001). Adjusting for BMI and lifestyle factors weakened, but did not eliminate these associations. All hormone and SHBG associations were stronger for WC than for waist-hip ratio or BMI. In age- and BMI-adjusted analyses men with a WC > or = 102 cm had significantly lower levels of total testosterone and SHBG compared to men with an optimal WC, defined as < 94 cm (12.3 vs. 13.9 nmol/l; p < 0.01 and 48.5 vs. 55.1 nmol/l; p < 0.001, respectively). The lowest levels of total and free testosterone were observed in men with relatively high WC despite relatively low overall obesity (BMI), suggesting that WC should be the preferred anthropometric measurement in predicting endogenous testosterone levels.
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Affiliation(s)
- Johan Svartberg
- Department of Medicine, University Hospital of North Norway, Tromsø, Norway.
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Veldhuis JD, Iranmanesh A, Keenan DM. Erosion of endogenous testosterone-driven negative feedback on pulsatile luteinizing hormone secretion in healthy aging men. J Clin Endocrinol Metab 2004; 89:5753-61. [PMID: 15531539 DOI: 10.1210/jc.2004-0399] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The present study tests the intuition that successful aging in men is marked by: 1) impaired feedforward by endogenous LH concentrations (con) of testosterone (Te) secretion (sec); and/or 2) attenuated feedback by unmanipulated Te con of LH sec. The goal was to assess both implicit linkages analytically without disrupting normal pathway coupling. This strategy required: 1) assay of paired LH and Te con sampled every 10 min for 24 h in 13 older (O) (ages 60-78 yr) and 13 young (Y) (ages 18-30 yr) men; 2) deconvolution-based estimation of LH and Te sec rates; 3) lag-specific cross-correlation analyses of the relationships between LH and Te con and sec; and 4) statistical contrasts by age stratum. Salient outcomes were: 1) O and Y men maintain comparable LH con drive of Te sec, viz maximal r = +0.51 and r = +0.52, respectively, at an optimal time lag of 50 min (both P < 0.001 against random LH and Te associations); 2) elderly subjects exhibit reduced Te con inhibition of LH sec [minimal r = -0.008 (O) vs. r = -0.10 (Y), P < 0.01 at a time lag of 40 min]; 3) mean (24-h) LH con do not differ by age; and 4) molar Te/sex hormone-binding globulin con are lower in the elderly than in Y individuals (P < 0.01).In conclusion, noninvasive analyses predict that attenuation of endogenous Te feedback restraint on the hypothalamo-pituitary unit may be an early biological marker of adaptive changes in the GnRH-LH-Te ensemble axis in the healthy O male.
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Affiliation(s)
- Johannes D Veldhuis
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, 200 First Street Southwest, Rochester, Minnesota 55905, USA.
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Abstract
The interpretation of the total serum testosterone concentration is problematic because it is related directly to the serum SHBG concentration.Frequently, an estimate of the serum free testosterone concentration is obtained to better assess the clinical status of the patient. We reviewed five methods for the determination of free testosterone or a surrogate test/index and the problems with these methods. The calculated free testosterone or BAT (highly positively correlated) are recommended as the preferred tests to assess biologically-active testosterone, although interlaboratory values may differ because standards are not available. The controversies in evaluating gonadal function are illustrated by the andropause (elevated SHBG) and obese men (decreased SHBG).
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Affiliation(s)
- Ronald J Elin
- Department of Pathology and Laboratory Medicine, University of Louisville School of Medicine, 512 South Hancock Street, #203, Louisville, KY 40202, USA.
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Abstract
The major goal of androgen substitution is to replace testosterone at levels as close to physiological levels as is possible. For some androgen-dependent functions testosterone is a pro-hormone, peripherally converted to 5alpha-dihydrotestosterone (DHT) and 17beta-estradiol (E2), of which the levels preferably should be within normal physiological ranges. Furthermore, androgens should have a good safety profile without adverse effects on the prostate, serum lipids, liver or respiratory function, and they must be convenient to use and patient-friendly, with a relative independence from medical services. Natural testosterone is viewed as the best androgen for substitution in hypogonadal men. The reason behind the selection is that testosterone can be converted to DHT and E2, thus developing the full spectrum of testosterone activities in long-term substitution. The mainstays of testosterone substitution are parenteral testosterone esters (testosterone enantate and testosterone cipionate) administered every 2-3 weeks. A major disadvantage is the strongly fluctuating levels of plasma testosterone, which are not in the physiological range at least 50% of the time. Also, the generated plasma E2 is usually supraphysiological. A major improvement is parenteral testosterone undecanoate producing normal plasma levels of testosterone for 12 weeks, with normal plasma levels of DHT and E2 also. Subcutaneous testosterone implants provide the patient, depending on the dose of implants, with normal plasma testosterone for 3-6 months. However, their use is not widespread. Oral testosterone undecanoate dissolved in castor oil bypasses the liver via its lymphatic absorption. At a dosage of 80 mg twice daily, plasma testosterone levels are largely in the normal range, but plasma DHT tends to be elevated. For two decades transdermal testosterone preparations have been available and have an attractive pharmacokinetic profile. Scrotal testosterone patches generate supraphysiological plasma DHT levels, which is not the case with the nonscrotal testosterone patches. Transdermal testosterone gel produces fewer skin irritations than the patches and offers greater flexibility in dosage. Oromucosal testosterone preparations have recently become available. Testosterone replacement is usually of long duration and so patient compliance is of utmost importance. Therefore, the patient must be involved in the selection of type of testosterone preparation. Administration of testosterone to young individuals has almost no adverse effects. With increasing age the risk of adverse effects on the prostate, the cardiovascular system and erythropoiesis increases. Consequently, short-acting testosterone preparations are better suited for aging androgen-deficient men.
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Affiliation(s)
- Louis J G Gooren
- Department of Endocrinology, Section of Andrology, VU University Medical Center, Amsterdam, The Netherlands.
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Delhez M, Hansenne M, Legros JJ. Andropause and psychopathology: minor symptoms rather than pathological ones. Psychoneuroendocrinology 2003; 28:863-74. [PMID: 12892654 DOI: 10.1016/s0306-4530(02)00102-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
This study examined the psychological symptomatology of men diagnosed with andropause and the association between calculated free testosterone (T) and depressed mood, anxiety and quality of life. Subjects were 153 men, aged 50-70 years, who participated in a screening of andropause. Total testosterone, FSH, LH and SHBG levels were measured. Depressed mood was assessed with the Carroll Rating Scale, anxiety with the "anxiety-insomnia" dimension of the General Health Questionnaire, and quality of life with the World Health Organisation Quality of Life questionnaire. The results showed that levels of free T decreased with age, whereas FSH and LH increased. Carroll Rating Scale scores were higher among hypogonadal subjects, but the mean score was low and not pathological. A negative correlation was observed between severity of depression as assessed by the Carroll Rating Scale and free T levels. However, subjects with a significant score on this scale did not exhibit different free T levels compared to subjects with a non-significant depressive score. Anxiety and quality of life did not differ between hypogonadal and eugonadal subjects. The present study therefore suggests that andropause is not characterised by specific psychological symptoms, but may be associated with "depressive symptoms" that are not considered as pathological.
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Affiliation(s)
- Marie Delhez
- Department of Endocrinology; Psychoneuroendocrinology Unit, CHU du Sart Tilman (B-35), B-4000 Liège, Belgium.
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Van Pottelbergh I, Goemaere S, Kaufman JM. Bioavailable estradiol and an aromatase gene polymorphism are determinants of bone mineral density changes in men over 70 years of age. J Clin Endocrinol Metab 2003; 88:3075-81. [PMID: 12843146 DOI: 10.1210/jc.2002-021691] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The question of whether and to what extent the sex steroid deficiency in elderly men contributes to the pathogenesis of bone loss has not been fully explored. The aim of the present study was to assess the association of serum bioavailable (Bio) estradiol (E(2)) with the evolution of bone mineral density (BMD) in 214 community-dwelling men aged 71-86 yr as well as the possible modulation of estrogen effects by a tetranucleotide (TTTA)(n)-repeat polymorphism of the CYP19 gene, which encodes the aromatase enzyme that converts androgens into estrogens. BMD was measured at yearly intervals over a period of 4 yr using dual x-ray absorptiometry. Fasting blood was analyzed at baseline for testosterone (T), E(2), and SHBG; the respective bioavailable fractions, BioT and BioE(2), were calculated. Serum BioE(2) was associated with baseline BMD at different assessed skeletal sites, with correlation coefficients ranging between 0.23 and 0.37 (P < 0.001). Estimated annual percentage change of BMD (%BMD) was -0.39% [95% confidence index (CI), -0.56, -0.22] at the total hip, -0.04% (95% CI, -0.29, 0.21) at the femoral neck, and -0.37% (95% CI, -0.45, -0.29) at the total distal forearm. Higher circulating BioE(2) levels were associated with less bone loss at the forearm and the hip (P < 0.05). The CYP19 gene (TTTA)(n)-repeat length (determined by fragment analysis) was not associated with baseline BMD in the total group of elderly men. However, a significant association was observed between the CYP19 genotype and BMD change at the distal forearm; the highest bone loss was observed in subjects homozygotic for the shortest observed allele length of (TTTA)(7)-repeats (P < 0.02). The CYP19 (TTTA)(n)-repeat length was not associated with either baseline BioE(2) or the BioT/BioE(2) ratio. In multiple linear regression models, the CYP19 genotype and serum BioE(2) were determinants of %BMD change at the forearm (P < 0.05). No significant contribution of BioT to %BMD change was evident. As to fracture risk, the allele containing the shortest (TTTA)(n)-repeat length was more represented not only in elderly men with a positive personal fracture history (Pearson's chi(2) test = 4.03; df = 1; P = 0.05) but also in study subjects with a positive fracture history in their first-degree relatives (Pearson's chi(2) test = 6.48; df = 1; P = 0.01). In conclusion, the results of this prospective observational study support the view that BioE(2) is a determinant of bone density changes in elderly men and, furthermore, provide an indication that the aromatase enzyme may exert a direct modulatory action on bone metabolism at the tissue level in elderly men.
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Affiliation(s)
- I Van Pottelbergh
- Department of Endocrinology, Ghent University Hospital, 9000 Ghent, Belgium
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Härkönen K, Huhtaniemi I, Mäkinen J, Hübler D, Irjala K, Koskenvuo M, Oettel M, Raitakari O, Saad F, Pöllänen P. The polymorphic androgen receptor gene CAG repeat, pituitary-testicular function and andropausal symptoms in ageing men. INTERNATIONAL JOURNAL OF ANDROLOGY 2003; 26:187-94. [PMID: 12755998 DOI: 10.1046/j.1365-2605.2003.00415.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The activity of androgen receptor (AR) is modulated by a polymorphic CAG trinucleotide repeat in the AR gene. In the present study, we investigated hormonal changes among ageing men, and whether the number of AR CAG triplets is related to the appearance of these changes, as well as symptoms and diseases associated with ageing. A total of 213 41-70-year-old men donated blood for hormone analyses (LH, testosterone, oestradiol and SHBG) and answered questions concerning diseases and symptoms associated with ageing and/or androgen deficiency. Of these men, 172 donated blood for the measurement of the CAG repeat length of AR. The CAG repeat region of the AR gene was amplified by polymerase chain reaction (PCR) and the products were sized on polyacrylamide gels. The repeat number was analysed as a dichotomized variable divided according to cut-off limits of the lowest (< or =20 repeats) and the highest quartile (> or =23 repeats), and as a continuous variable. The proportion of men with serum LH in the uppermost quartile (>6.0 IU/L) with normal serum testosterone (>9.8 nmol/L, above the lowest 10%) increased significantly with age (p = 0.01). There were fewer men with this hormonal condition among those with CAG repeat number in the uppermost quartile (> or =23 repeats) (p = 0.03). These men also reported less decreased potency (p < 0.05). The repeat number was positively correlated with depression, as expressed by the wish to be dead (r = 0.45; p < 0.0001), depressed mood (r = 0.23; p = 0.003), anxiety (r = 0.15; p < 0.05), deterioration of general well-being (r = 0.22; p = 0.004), as well as decreased beard growth (r = 0.49; p < 0.0001). A hormonal condition where serum testosterone is normal but LH increased is a frequent finding in male ageing. Only certain types of age-related changes in ageing men were associated with the length of the AR gene CAG repeat, suggesting that this parameter may play a role in setting different thresholds for the array of androgen actions in the male.
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Affiliation(s)
- Kati Härkönen
- Department of Medical Genetics, University of Turku, Finland.
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Pandi-Perumal SR, Seils LK, Kayumov L, Ralph MR, Lowe A, Moller H, Swaab DF. Senescence, sleep, and circadian rhythms. Ageing Res Rev 2002; 1:559-604. [PMID: 12067601 DOI: 10.1016/s1568-1637(02)00014-4] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The goal of this review article is to summarize our knowledge and understanding of the overlapping (interdisciplinary) areas of senescence, sleep, and circadian rhythms. Our overview comprehensively (and visually wherever possible), emphasizes the organizational, dynamic, and plastic nature of both sleep and circadian timing system (CTS) during senescent processes in animals and in humans. In this review, we focus on the studies that deal with sleep and circadian rhythms in aged animals and how these studies have closely correlated to and advanced our understanding of similar processes in ageing humans. Our comprehensive summary of various aspects of the existing research on animal and human ageing, both normal and pathological, presented in this review underscores the invaluable advantage of close collaboration between clinicians and basic research scientists and the future challenges inherent in this collaboration. First, our review addresses the common age-related changes that occur in sleep and temporal organization of both animals and humans. Second, we examine the specific modifications that often accompany sleep and CTS during aging. Third, we discuss the clinical epidemiology of sleep dysfunctions during ageing and their current clinical management, both pharmacological and non-pharmacological. Finally, we predict the possible future promises for complementary and alternative medicine (CAM) that pave the way to the emergence of a "Holistic Sleep Medicine" approach to the treatment of sleep disorders in the ageing population. Further studies will provide additional valuable insights into the understanding of both sleep and circadian rhythms during senescence.
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Affiliation(s)
- S R Pandi-Perumal
- Department of Physiology, UCLA School of Medicine, Los Angeles, CA 90095, USA.
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Matsumoto AM. Andropause: clinical implications of the decline in serum testosterone levels with aging in men. J Gerontol A Biol Sci Med Sci 2002; 57:M76-99. [PMID: 11818427 DOI: 10.1093/gerona/57.2.m76] [Citation(s) in RCA: 274] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Alvin M Matsumoto
- Department of Medicine, Division of Gerontology and Geriatric Medicine, Population Center for Research in Reproduction, University of Washington School of Medicine, Seattle, WA, USA.
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Keenan DM, Veldhuis JD. Disruption of the hypothalamic luteinizing hormone pulsing mechanism in aging men. Am J Physiol Regul Integr Comp Physiol 2001; 281:R1917-24. [PMID: 11705778 DOI: 10.1152/ajpregu.2001.281.6.r1917] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The incremental nature of neuroendocrine aging suggests that subtle system dysregulation may precede overt axis failure. The present analyses unmask threefold disruption of pulsatile gonadotropin-releasing hormone (GnRH)-luteinizing hormone (LH) secretion in the aging male. First, by way of random effects-based deconvolution analysis, we document an elevated daily GnRH-LH pulse frequency in healthy older men [namely, mean (+/-SE) 23 +/- 1 (older) vs. 15 +/- 1 (young) LH secretory bursts/24 h, P < 0.001] and lower mean LH pulse mass [3.73 +/- 0.58 (older) vs. 5.46 +/- 0.66 (young) IU/l, P = 0.038]. However, total LH secretion rates and two-compartment LH elimination kinetics were comparable in the two age cohorts. Second, using the approximate entropy statistic, we show an equivalently random order-dependent succession of LH interpulse-interval lengths in young and older men, but a marked age-related deterioration of the ad seriatim regularity of LH pulse mass series in older individuals (P = 0.0057). Third, by modeling GnRH pulse-generator output as a Weibull renewal process (generalized Gamma density) to emulate loosely coupled GnRH neuronal oscillators, we identify an age-related reduction in the frequency-independent and order-independent variability of GnRH-LH interpulse-interval sets (P = 0.08). These findings indicate that the GnRH-LH pulsing mechanism in healthy older men maintains an increased mean frequency and lower amplitude of bursting activity, a reduced uniformity of serial LH pulse-mass values, and an impaired variability among interpulse-interval lengths. Thereby, the foregoing order-dependent and order-independent alterations in GnRH-LH signal generation in the aging human suggest a general framework for exploring subtle disruption of time-sensitive regulation of other neurointegrative systems.
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Affiliation(s)
- D M Keenan
- Department of Statistics, University of Virginia, Charlottesville, VA 22903, USA
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Van Pottelbergh I, Lumbroso S, Goemaere S, Sultan C, Kaufman JM. Lack of influence of the androgen receptor gene CAG-repeat polymorphism on sex steroid status and bone metabolism in elderly men. Clin Endocrinol (Oxf) 2001; 55:659-66. [PMID: 11894978 DOI: 10.1046/j.1365-2265.2001.01403.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Population means for serum testosterone (T) levels in healthy men decrease with ageing but there is considerable interindividual variability of serum T in elderly men. Ultimate androgen action is mediated through the androgen receptor. Subtle differences in androgen sensitivity might contribute to serum T variability through the T negative feedback regulation. The androgen receptor gene (AR) contains in exon 1 a polymorphic trinucleotide CAG-repeat, whose length modulates androgen receptor action. The aims of the study were to assess the potential contribution of the AR CAG-repeat polymorphism in the interindividual variability of serum T and in the determination of bone metabolism in ambulatory elderly men. DESIGN AND PATIENTS We used cross-sectional baseline data of a longitudinal study investigating the process of ageing, in particular the changes in hormonal status and bone metabolism, in a cohort of 273 community-dwelling healthy men, between age 71 and 86 years. MEASUREMENTS AR CAG-repeat length was determined by automated DNA sequencing of exon 1 of the AR gene. Serum T, sex hormone binding globulin, LH and oestradiol were measured by specific immunoassays. Bone mineral density (BMD) was determined by dual energy X-ray absorptiometry. Bone turnover was assessed by measurement of serum bone-specific alkaline phosphatase, serum osteocalcin, serum C-terminal type I procollagen peptide, serum and urinary C-terminal telopeptides of type I collagen and urinary deoxypyridinoline levels, with use of immunoassays. RESULTS No significant association was found between the AR CAG-repeat length and either total or free T, LH or the androgen sensitivity index (LHxT). BMD measurements at the hip and the forearm were not associated with AR CAG-repeat length and there was no association of this AR polymorphism with any of the biochemical markers of bone turnover. Results were not different after adjustments for age and body mass index. CONCLUSIONS The findings of the present study do not support the view that in community-dwelling, healthy elderly men the androgen receptor gene CAG-repeat polymorphism has a substantial impact on interindividual variability of serum testosterone levels or on the determination of bone turnover and bone mineral density.
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Affiliation(s)
- I Van Pottelbergh
- Unit for Osteoporosis and Metabolic Bone Diseases, Ghent University Hospital, Gent, Belgium
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van den Berghe G, Weekers F, Baxter RC, Wouters P, Iranmanesh A, Bouillon R, Veldhuis JD. Five-day pulsatile gonadotropin-releasing hormone administration unveils combined hypothalamic-pituitary-gonadal defects underlying profound hypoandrogenism in men with prolonged critical illness. J Clin Endocrinol Metab 2001; 86:3217-26. [PMID: 11443192 DOI: 10.1210/jcem.86.7.7680] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Central hyposomatotropism and hypothyroidism have been inferred in long-stay intensive care patients. Pronounced hypoandrogenism presumably also contributes to the catabolic state of critical illness. Accordingly, the present study appraises the mechanism(s) of failure of the gonadotropic axis in prolonged critically ill men by assessing the effects of pulsatile GnRH treatment in this unique clinical context. To this end, 15 critically ill men (mean +/- SD age, 67 +/- 12 yr; intensive care unit stay, 25 +/- 9 days) participated, with baseline values compared with those of 50 age- and BMI-matched healthy men. Subjects were randomly allocated to 5 days of placebo or pulsatile iv GnRH administration (0.1 microg/kg every 90 min). LH, GH, and TSH secretion was quantified by deconvolution analysis of serum hormone concentration-time series obtained by sampling every 20 min from 2100-0600 h at baseline and on nights 1 and 5 of treatment. Serum concentrations of gonadal and adrenal steroids, T(4), T(3), insulin-like growth factor I (IGF), and IGF-binding proteins as well as circulating levels of cytokines and selected metabolic markers were measured. During prolonged critical illness, pulsatile LH secretion and mean LH concentrations (1.8 +/- 2.2 vs. 6.0 +/- 2.2 IU/L) were low in the face of extremely low circulating total testosterone (0.27 +/- 0.18 vs. 12.7 +/- 4.07 nmol/L; P < 0.0001) and relatively low estradiol (E(2); 58.3 +/- 51.9 vs. 85.7 +/- 18.6 pmol/L; P = 0.009) and sex hormone-binding globulin (39.1 +/- 11.7 vs. 48.6 +/- 27.8 nmol/L; P = 0.01). The molar ratio of E(2)/T was elevated 37-fold in ill men (P < 0.0001) and correlated negatively with the mean serum LH concentrations (r = -0.82; P = 0.0002). Pulsatile GH and TSH secretion were suppressed (P < or = 0.0004), as were mean serum IGF-I, IGF-binding protein-3, and acid-labile subunit concentrations; thyroid hormone levels; and dehydroepiandrosterone sulfate. Morning cortisol was within the normal range. Serum interleukin-1beta concentrations were normal, whereas interleukin-6 and tumor necrosis factor-alpha were elevated. Serum tumor necrosis factor-alpha was positively correlated with the molar E(2)/testosterone ratio and with type 1 procollagen; the latter was elevated, whereas osteocalcin was decreased. Ureagenesis and breakdown of bone were increased. C-Reactive protein and white blood cell counts were elevated; serum lactate levels were normal. Intermittent iv GnRH administration increased pulsatile LH secretion compared with placebo by an increment of +8.1 +/- 8.1 IU/L at 24 h (P = 0.001). This increase was only partially maintained after 5 days of treatment. GnRH pulses transiently increased serum testosterone by +174% on day 2 (P = 0.05), whereas all other endocrine parameters remained unaltered. GnRH tended to increase type 1 procollagen (P = 0.06), but did not change serum osteocalcin levels or bone breakdown. Ureagenesis was suppressed (P < 0.0001), and white blood cell count (P = 0.0001), C-reactive protein (P = 0.03), and lactate level (P = 0.01) were increased by GnRH compared with placebo infusions. In conclusion, hypogonadotropic hypogonadism in prolonged critically ill men is only partially overcome with exogenous iv GnRH pulses, pointing to combined hypothalamic-pituitary-gonadal origins of the profound hypoandrogenism evident in this context. In view of concomitant central hyposomatotropism and hypothyroidism, evaluating the effectiveness of pulsatile GnRH intervention together with GH and TSH secretagogues will be important.
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Affiliation(s)
- G van den Berghe
- Department of Intensive Care Medicine, University Hospital Gasthuisberg, University of Leuven, B-3000 Leuven, Belgium.
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Keenan DM, Veldhuis JD. Hypothesis testing of the aging male gonadal axis via a biomathematical construct. Am J Physiol Regul Integr Comp Physiol 2001; 280:R1755-71. [PMID: 11353681 DOI: 10.1152/ajpregu.2001.280.6.r1755] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neuroendocrine axes are feedback- and feedforward-coupled dynamic ensembles. Disruption of selected pathways in such networklike organizations may explicate loss of orderly hormonal output as observed in aging. To test this notion more explicitly, we implemented an earlier computer-assisted biomathematical model of the interlinked male hypothalamo [gonadotropin-releasing hormone (GnRH)]-pituitary [luteinizing hormone, (LH)]-testicular [Leydig cell testosterone (Te)] axis ( Am J Physiol Endocrinol Metab Physiol 275: E157–E176, 1988; Keenan D., W. Sun, and J. D. Veldhuis, SIAM J Appl Math 61: 934–965, 2000). Thereby, we appraise mechanistic hypotheses for more disorderly LH and Te secretion in aging men. We compare model predictions with monitored abnormalities in the older male, namely, irregular patterns of individual and synchronous LH and Te release, reduced 24-h rhythmic Te output, and variably elevated LH secretion. Among the mechanisms examined, the most parsimonious aging hypothesis would entail impaired LH feedforward on Te without or with attenuated Te feedback on GnRH/LH secretion. This investigative strategy should aid in exploring new postulates of disrupted feedback networks in pathophysiology.
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Affiliation(s)
- D M Keenan
- Department of Statistics, University of Virginia, Charlottesville, Virginia 22903, USA
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45
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Paulson RJ, Milligan RC, Sokol RZ. The lack of influence of age on male fertility. Am J Obstet Gynecol 2001; 184:818-22; discussion 822-4. [PMID: 11303188 DOI: 10.1067/mob.2001.113852] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
OBJECTIVE This study was undertaken to determine the effect of male aging on sperm quality as determined by semen analysis, the fertilization rate of human oocytes in vitro, and live birth rates. STUDY DESIGN Retrospective analysis correlating outcome measures with male age was performed for 558 oocyte donation cycles in 441 couples. The oocyte donation model was chosen because it controls for oocyte quality and endometrial receptivity, which allows variations in sperm quality as a function of male age to be the only dependent variable. Outcome measures analyzed were semen analysis, fertilization rates in vitro, pregnancy rates, live birth rates, and cumulative live birth rates by life-table analysis. RESULTS There was a negative correlation between male age and total sperm count, but there was no correlation between male age and any of the other parameters in the semen analysis. There was no association between male age and the fertilization rate of donated oocytes in vitro, pregnancy rates, or live birth rates. Recipient couples were grouped by quartiles of male age, and cumulative live birth rates were the same in the 4 groups. CONCLUSION Whereas male aging is associated with a significant decline in total sperm count, this change is not reflected in a decreased fertilization rate or a decreased live birth rate in the oocyte donation model.
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Affiliation(s)
- R J Paulson
- Division of Reproductive Endocrinology and Infertility, the Department of Obstetrics and Gynecology, University of Southern California Keck School of Medicine, Los Angeles, USA
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Abstract
We recently identified consistent attenuation of LH and testosterone secretory pulse amplitude and associated disruption of their orderly patterns of release in healthy older men. These dynamic changes emerge despite young-adult concentrations of LH and total testosterone. Moreover, we could document disruption of synchrony between LH secretion and oscillations in FSH, prolactin, sleep-stage and NPT (nocturnal penile tumescence), thus pointing to loss of coordinate neurohormone outflow. Such data suggest that CNS-hypothalamically based regulatory defects may be important in aging, as inferred indirectly in the old male rat and mouse more than 15 years ago. How such alterations are related to specific hypothalamic neurotransmitter changes in aging will be critical to unravel.
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Affiliation(s)
- J D Veldhuis
- Division of Endocrinology, Department of Internal Medicine, General Clinical Research Center, University of Virginia School of Medicine, 22908-0202, Charlottesville, VA, USA.
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47
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Affiliation(s)
- A Vermeulen
- Endocrinology Section, Department of Internal Medicine, University Hospital, Ghent, Belgium
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48
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Veldhuis JD, Iranmanesh A, Godschalk M, Mulligan T. Older men manifest multifold synchrony disruption of reproductive neurohormone outflow. J Clin Endocrinol Metab 2000; 85:1477-86. [PMID: 10770185 DOI: 10.1210/jcem.85.4.6546] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Under a working clinical hypothesis that aging putatively disrupts neuroendocrine control mechanisms, here we test a specific corollary notion that transitions in sleep stage, oscillations in nocturnal penile tumescence (NPT; a neurogenically organized signal), and the rates of instantaneous secretion of LH and/or testosterone are jointly synchronous in healthy young, but not older, men. To this end, we evaluated 10 young (aged 21-31 yr) and 8 older (aged 65-74 yr) men by intensive overnight multisite monitoring, viz. simultaneous electro-encephalogram and NPT recordings (every 30 s) and remote blood sampling (every 2.5 min) to quantitate LH and testosterone release. Waveform-independent deconvolution and cross-correlation analyses of these neurohormone outflow measures revealed that healthy young men sustain four salient physiological linkages overnight: 1) a strong inverse (confirmatory) relationship between sleep stage and NPT activity, such that deeper sleep is accompanied by suppression of NPT; 2) consistent coupling between NPT and testosterone secretion, wherein heightened NPT activity respectively precedes and follows increased testosterone secretion by 12.5-32.5 and 50-60 min; 3) evident synchrony between sleep stage and testosterone secretion, in which testosterone secretion increases over a 30-min window (-2.5 to 25 min) while sleep deepens; and 4) a close temporal linkage between instantaneous LH release and NPT oscillations, whereby LH secretion increases 55-62.5 min before and again 5-30 min after NPT declines. In contrast, older men manifested global loss of expected young adult synchrony; namely, 1) abolition of the inverse relationship between sleep stage and NPT, 2) decorrelation of NPT oscillations and testosterone secretion, 3) decoupling of testosterone release and deep sleep, and 4) abrogation of the linkage between LH secretion and penile detumescence. In summary, high intensity overnight monitoring of multiple reproductive neuroendocrine outflow measures simultaneously in young men delineates prominent neurophysiological coupling among sleep transitions and NPT activity, LH and testosterone secretion or NPT oscillations, and testosterone secretion and deepening sleep stage. In contrast, healthy older men exhibit near-universal disruption of physiological young adult synchronicity. Thus, we conclude that male reproductive aging is marked by erosion of coordinate regulation among sleep transitions, central nervous system-directed NPT activity, and hypothalamically driven episodic GnRH/LH (and thereby Leydig cell testosterone) secretion. Whether analogous multifold uncoupling of neurohormone signals emerges in the course of reproductive aging in women or in nonhuman species is not yet known.
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Affiliation(s)
- J D Veldhuis
- Department of Internal Medicine, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
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Abstract
Although, in distinction to middle aged women, in middle aged men there does not occur a sudden arrest of gonadal functions, fertility persisting until very old age, aging in men is, nevertheless, associated with an gradual decline of both endo- and exocrine testicular function. Whereas age has in fact only minimal effects on the quality of the ejaculate, endocrine function declines steadily with age and at age 75 years, mean plasma testosterone levels are only 65% of levels in young adults whereas over 25%, of these men have bioavailable testosterone levels below the lower normal limit in young adults. The interindividual variations in the plasma levels are, however, very important and a quarter of men over 75 years old, have still testosterone levels within the upper quartile of values in young men. Aging is accompanied by a series of signs and symptoms, many of which are rather similar to those observed in young hypogonadal males. The etiology of these signs and symptoms is often multifactorial, and very few correlations have been found between symptoms and plasma testosterone levels. Nevertheless, there is good evidence that the age associated decrease in testosterone levels is at least a co-determinant of these symptoms and testosterone supplementation has shown favorable effects on many of them. Side effects of this substitutive therapy are minimal when care is taken to keep plasma testosterone levels within the physiological range. Clinical prostatic carcinoma is an absolute contra-indication for testosterone supplementation. So far, there are no indications that testosterone would stimulate the evolution of as subclinical prostatic carcinoma to a clinical carcinoma but it should be recalled that so far, only a small number of elderly males received substitutive androgen treatment for longer periods in controlled studies. Hence, although side effects are generally minimal, one should, nevertheless, await the results of larger, long term, well-controlled studies before to recommend the routine testosterone substitution of elderly men.
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Affiliation(s)
- A Vermeulen
- Medical Clinic, University Hospital, Gent, Belgium
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Fink G, Sumner B, Rosie R, Wilson H, McQueen J. Androgen actions on central serotonin neurotransmission: relevance for mood, mental state and memory. Behav Brain Res 1999; 105:53-68. [PMID: 10553690 DOI: 10.1016/s0166-4328(99)00082-0] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Sex steroids exert potent effects on mood and mental state in the human. Our previous experimental findings in female rats suggest that these effects may be mediated, in part, by the action of estrogen on the 5-hydroxytryptamine2A receptor (5-HT(2A)R) and serotonin transporter (SERT) in brain. Here we review our recent findings on the effect of acute (approximately 32 h) testosterone manipulation on central 5-HT(2A)R and SERT in male rats. Castration decreased while testosterone or estrogen, but not 5alpha-dihydrotestosterone (5alpha-DHT), increased significantly the content of 5-HT(2A)R mRNA and SERT mRNA in the dorsal raphe nucleus (DR) and the density of 5-HT(2A)R and SERT binding sites in higher centers of the brain. The lack of effect of 5alpha-DHT, a potent androgen which cannot be converted to estrogen, suggests that the action of testosterone depends upon its conversion to estrogen by aromatase. This may also explain why estrogen, but not testosterone or 5alpha-DHT, increased the density of 5-HT(2A)R binding sites in the caudate-putamen, a brain region where aromatase is scarce. The estrogen induction of SERT mRNA is most prominent in the rostral DR and this together with the correlation between sensitivity of DR serotonin neurons to estrogen and neurotoxic amphetamine derivatives provides a potential topochemical handle with which to investigate testosterone/estrogen regulation of SERT gene expression. These findings are discussed in relation to the possible role of interactions between sex steroids and serotonin mechanisms in mood disorders, schizophrenia and Alzheimer's disease.
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Affiliation(s)
- G Fink
- MRC Brain Metabolism Unit, University Department of Neuroscience, Edinburgh, UK.
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