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Labarthe A, Zizzari P, Fiquet O, Lebrun N, Veldhuis JD, Roelfsema F, Chauveau C, Bohlooly-Y M, Epelbaum J, Tolle V. Effect of Growth Hormone Secretagogue Receptor Deletion on Growth, Pulsatile Growth Hormone Secretion, and Meal Pattern in Male and Female Mice. Neuroendocrinology 2022; 112:215-234. [PMID: 33774644 DOI: 10.1159/000516147] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 03/25/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION While the vast majority of research investigating the role of ghrelin or its receptor, GHS-R1a, in growth, feeding, and metabolism has been conducted in male rodents, very little is known about sex differences in this system. Furthermore, the role of GHS-R1a signaling in the control of pulsatile GH secretion and its link with growth or metabolic parameters has never been characterized. METHODS We assessed the sex-specific contribution of GHS-R1a signaling in the activity of the GH/IGF-1 axis, metabolic parameters, and feeding behavior in adolescent (5-6 weeks old) or adult (10-19 weeks old) GHS-R KO (Ghsr-/-) and WT (Ghsr+/+) male and female mice. RESULTS Adult Ghsr-/- male and female mice displayed deficits in weight and linear growth that were correlated with reduced GH pituitary contents in males only. GHS-R1a deletion was associated with reduced meal frequency and increased meal intervals, as well as reduced hypothalamic GHRH and NPY mRNA in males, not females. In adult, GH release from Ghsr-/- mice pituitary explants ex vivo was reduced independently of the sex. However, in vivo pulsatile GH secretion decreased in adult but not adolescent Ghsr-/- females, while in males, GHS-R1a deletion was associated with reduction in pulsatile GH secretion during adolescence exclusively. In males, linear growth did not correlate with pulsatile GH secretion, but rather with ApEn, a measure that reflects irregularity of the rhythmic secretion. Fat mass, plasma leptin concentrations, or ambulatory activity did not predict differences in GH secretion. DISCUSSION/CONCLUSION These results point to a sex-dependent dimorphic effect of GHS-R1a signaling to modulate pulsatile GH secretion and meal pattern in mice with different compensatory mechanisms occurring in the hypothalamus of adult males and females after GHS-R1a deletion. Altogether, we show that GHS-R1a signaling plays a more critical role in the regulation of pulsatile GH secretion during adolescence in males and adulthood in females.
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Affiliation(s)
- Alexandra Labarthe
- Université de Paris, UMRS_1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Philippe Zizzari
- Université de Paris, UMRS_1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Oriane Fiquet
- Université de Paris, UMRS_1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Nicolas Lebrun
- Université de Paris, UMRS_1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Johannes D Veldhuis
- Endocrine Research Unit, Department of Medicine, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, New York, USA
| | - Ferdinand Roelfsema
- Department of Internal Medicine, Section of Endocrinology and Metabolism, Leiden University Medical Center, Leiden, The Netherlands
| | - Christophe Chauveau
- Marrow Adiposity and Bone Lab - MABLab ULR 4490, University Littoral Côte d'Opale, Boulogne-sur-Mer, France
- University Lille, CHU Lille, Lille, France
| | - Mohammad Bohlooly-Y
- Translational Genomics, Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Jacques Epelbaum
- Université de Paris, UMRS_1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
- UMR CNRS/MNHN 7179, Mécanismes Adaptatifs et Evolution, Brunoy, France
| | - Virginie Tolle
- Université de Paris, UMRS_1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
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Hassouna R, Fernandez G, Lebrun N, Fiquet O, Roelfsema F, Labarthe A, Zizzari P, Tomasetto C, Epelbaum J, Viltart O, Chauveau C, Perello M, Tolle V. Ghrelin Gene Deletion Alters Pulsatile Growth Hormone Secretion in Adult Female Mice. Front Endocrinol (Lausanne) 2021; 12:754522. [PMID: 34721302 PMCID: PMC8549963 DOI: 10.3389/fendo.2021.754522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 09/16/2021] [Indexed: 11/13/2022] Open
Abstract
Using preproghrelin-deficient mice (Ghrl-/-), we previously observed that preproghrelin modulates pulsatile growth hormone (GH) secretion in post-pubertal male mice. However, the role of ghrelin and its derived peptides in the regulation of growth parameters or feeding in females is unknown. We measured pulsatile GH secretion, growth, metabolic parameters and feeding behavior in adult Ghrl-/- and Ghrl+/+ male and female mice. We also assessed GH release from pituitary explants and hypothalamic growth hormone-releasing hormone (GHRH) expression and immunoreactivity. Body weight and body fat mass, linear growth, spontaneous food intake and food intake following a 48-h fast, GH pituitary contents and GH release from pituitary explants ex vivo, fasting glucose and glucose tolerance were not different among adult Ghrl-/- and Ghrl+/+ male or female mice. In vivo, pulsatile GH secretion was decreased, while approximate entropy, that quantified orderliness of secretion, was increased in adult Ghrl-/- females only, defining more irregular GH pattern. The number of neurons immunoreactive for GHRH visualized in the hypothalamic arcuate nucleus was increased in adult Ghrl-/- females, as compared to Ghrl+/+ females, whereas the expression of GHRH was not different amongst groups. Thus, these results point to sex-specific effects of preproghrelin gene deletion on pulsatile GH secretion, but not feeding, growth or metabolic parameters, in adult mice.
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Affiliation(s)
- Rim Hassouna
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Gimena Fernandez
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Nicolas Lebrun
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Oriane Fiquet
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Ferdinand Roelfsema
- Department of Internal Medicine, Section of Endocrinology and Metabolism, Leiden University Medical Center, Leiden, Netherlands
| | - Alexandra Labarthe
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Philippe Zizzari
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
| | - Catherine Tomasetto
- Institut de génétique et de biologie moléculaire et cellulaire (IGBMC), UMR7104 CNRS/U1258 INSERM, Université de Strasbourg, Illkirch, France
| | - Jacques Epelbaum
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
- UMR CNRS/MNHN 7179, Mécanismes Adaptatifs et Evolution, Brunoy, France
| | - Odile Viltart
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
- Université de Lille, Faculté des Sciences et Technologies, Villeneuve d’Ascq, France
| | - Christophe Chauveau
- Marrow Adiposity and Bone Lab - MABLab ULR 4490, Univ. Littoral Côte d’Opale, Boulogne-sur-Mer, Univ. Lille and CHU Lille, Lille, France
| | - Mario Perello
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Virginie Tolle
- Université de Paris, UMR-S 1266 INSERM, Institute of Psychiatry and Neuroscience of Paris, Paris, France
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Gibbison B, Keenan DM, Roelfsema F, Evans J, Phillips K, Rogers CA, Angelini GD, Lightman SL. Dynamic Pituitary-Adrenal Interactions in the Critically Ill after Cardiac Surgery. J Clin Endocrinol Metab 2020; 105:dgz206. [PMID: 31738827 PMCID: PMC7089849 DOI: 10.1210/clinem/dgz206] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 11/15/2019] [Indexed: 11/19/2022]
Abstract
CONTEXT Patients with critical illness are thought to be at risk of adrenal insufficiency. There are no models of dynamic hypothalamic-pituitary-adrenal (HPA) axis function in this group of patients and thus current methods of diagnosis are based on aggregated, static models. OBJECTIVE To characterize the secretory dynamics of the HPA axis in the critically ill (CI) after cardiac surgery. DESIGN Mathematical modeling of cohorts. SETTING Cardiac critical care unit. PATIENTS 20 male patients CI at least 48 hours after cardiac surgery and 19 healthy (H) male volunteers. INTERVENTIONS None. MAIN OUTCOME MEASURES Measures of hormone secretory dynamics were generated from serum adrenocorticotrophic hormone (ACTH) sampled every hour and total cortisol every 10 min for 24 h. RESULTS All CI patients had pulsatile ACTH and cortisol profiles. CI patients had similar ACTH secretion (1036.4 [737.6] pg/mL/24 h) compared to the H volunteers (1502.3 [1152.2] pg/mL/24 h; P = .20), but increased cortisol secretion (CI: 14 447.0 [5709.3] vs H: 5915.5 [1686.7)] nmol/L/24 h; P < .0001). This increase in cortisol was due to nonpulsatile (CI: 9253.4 [3348.8] vs H: 960 [589.0] nmol/L/24 h, P < .0001), rather than pulsatile cortisol secretion (CI: 5193.1 [3018.5] vs H: 4955.1 [1753.6] nmol/L/24 h; P = .43). Seven (35%) of the 20 CI patients had cortisol pulse nadirs below the current international guideline threshold for critical illness-related corticosteroid insufficiency, but an overall secretion that would not be considered deficient. CONCLUSIONS This study supports the premise that current tests of HPA axis function are unhelpful in the diagnosis of adrenal insufficiency in the CI. The reduced ACTH and increase in nonpulsatile cortisol secretion imply that the secretion of cortisol is driven by factors outside the HPA axis in critical illness.
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Affiliation(s)
- Ben Gibbison
- Department of Anaesthesia, Bristol Medical School, University of Bristol, Bristol, UK
| | - Daniel M Keenan
- Department of Statistics, University of Virginia, Charlottesville, VA, US
| | - Ferdinand Roelfsema
- Department of Internal Medicine, Section Endocrinology, University of Leiden, Leiden, The Netherlands
| | - Jon Evans
- Clinical Trials and Evaluation Unit, Bristol Trials Centre, University of Bristol, Bristol, UK
| | - Kirsty Phillips
- Department of Pathology, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Chris A Rogers
- Clinical Trials and Evaluation Unit, Bristol Trials Centre, University of Bristol, Bristol, UK
| | - Gianni D Angelini
- Department of Cardiac Surgery, Bristol Medical School, University of Bristol, Bristol, UK
| | - Stafford L Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
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Keenan DM, Veldhuis JD, Basu A, Basu R. A novel measure of glucose homeostasis (or loss thereof) comprising the joint dynamics of glucose, insulin, glucagon, and cortisol. Am J Physiol Endocrinol Metab 2019; 316:E998-E1011. [PMID: 30860881 PMCID: PMC6620575 DOI: 10.1152/ajpendo.00078.2018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Quantification of disturbances in glucose-insulin homeostasis has been the cornerstone of appraising insulin resistance and detecting early-stage diabetes. Metabolic homeostasis arises from feedback and feed-forward interactions among (at least) all four of glucose, insulin, glucagon, and cortisol. Quantifying such tetrapartite interactions in the fasting (endogenously regulated) state overnight could elucidate very early regulatory disruption. In the present study, healthy subjects without diabetes (ND; n = 20) and patients with Type 2 diabetes (T2D; n = 21) were investigated by repeated overnight blood sampling of all four of glucose, insulin, glucagon, and cortisol concentrations. To obviate confounding by hormone-specific disappearance rates, analyses were performed at the level of production (glucose) or secretion (insulin, glucagon, and cortisol) rates estimated by regularized deconvolution analysis. Then, a novel method for quantifying the loss of homeostasis among glucose, insulin, and glucagon (and, when available, cortisol) secretion patterns was developed. Potential early stage prediabetic candidates were identified. The new methodology avoids many of the difficulties encountered in the conventional estimation of insulin-glucose sensitivity or resistance, while incorporating the dynamics of the key coregulators under fasting conditions.
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Affiliation(s)
- Daniel M Keenan
- Department of Statistics, University of Virginia , Charlottesville, Virginia
| | - Johannes D Veldhuis
- Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic , Rochester, Minnesota
| | - Ananda Basu
- Division of Endocrinology, Center of Diabetes Technology, University of Virginia School of Medicine , Charlottesville, Virginia
| | - Rita Basu
- Division of Endocrinology, Center of Diabetes Technology, University of Virginia School of Medicine , Charlottesville, Virginia
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Keenan DM, Veldhuis JD. Pulsatility of Hypothalamo-Pituitary Hormones: A Challenge in Quantification. Physiology (Bethesda) 2017; 31:34-50. [PMID: 26674550 DOI: 10.1152/physiol.00027.2015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neuroendocrine systems control many of the most fundamental physiological processes, e.g., reproduction, growth, adaptations to stress, and metabolism. Each such system involves the hypothalamus, the pituitary, and a specific target gland or organ. In the quantification of the interactions among these components, biostatistical modeling has played an important role. In the present article, five key challenges to an understanding of the interactions of these systems are illustrated and discussed critically.
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Affiliation(s)
- Daniel M Keenan
- Department of Statistics, University of Virginia, Charlottesville, Virginia; and
| | - Johannes D Veldhuis
- Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota
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Characterization of the Hypothalamic-Pituitary-Adrenal-Axis in Familial Longevity under Resting Conditions. PLoS One 2015; 10:e0133119. [PMID: 26193655 PMCID: PMC4508039 DOI: 10.1371/journal.pone.0133119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 06/24/2015] [Indexed: 12/04/2022] Open
Abstract
Objective The hypothalamic-pituitary-adrenal (HPA)-axis is the most important neuro-endocrine stress response system of our body which is of critical importance for survival. Disturbances in HPA-axis activity have been associated with adverse metabolic and cognitive changes. Humans enriched for longevity have less metabolic and cognitive disturbances and therefore diminished activity of the HPA axis may be a potential candidate mechanism underlying healthy familial longevity. Here, we compared 24-h plasma ACTH and serum cortisol concentration profiles and different aspects of the regulation of the HPA-axis in offspring from long-lived siblings, who are enriched for familial longevity and age-matched controls. Design Case-control study within the Leiden Longevity study cohort consisting of 20 middle-aged offspring of nonagenarian siblings (offspring) together with 18 partners (controls). Methods During 24 h, venous blood was sampled every 10 minutes for determination of circulatory ACTH and cortisol concentrations. Deconvolution analysis, cross approximate entropy analysis and ACTH-cortisol-dose response modeling were used to assess, respectively, ACTH and cortisol secretion parameters, feedforward and feedback synchrony and adrenal gland ACTH responsivity. Results Mean (95% Confidence Interval) basal ACTH secretion was higher in male offspring compared to male controls (645 (324-1286) ngl/L/24 h versus 240 (120-477) ng/L/24 h, P = 0.05). Other ACTH and cortisol secretion parameters did not differ between offspring and controls. In addition, no significant differences in feedforward and feedback synchrony and adrenal gland ACTH responsivity were observed between groups. Conclusions These results suggest that familial longevity is not associated with major differences in HPA-axis activity under resting conditions, although modest, sex-specific differences may exist between groups that might be clinically relevant.
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Sharma AN, Wigham J, Veldhuis JD. Corticotropic axis drive of overnight cortisol secretion is suppressed in adolescents and young adults with type 1 diabetes mellitus. Pediatr Diabetes 2014; 15:444-52. [PMID: 24350820 PMCID: PMC4062617 DOI: 10.1111/pedi.12108] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/01/2013] [Accepted: 11/18/2013] [Indexed: 12/28/2022] Open
Abstract
CONTEXT Type 1 diabetes mellitus (T1DM) is a pro-inflammatory stress state, which, with its attendant hyperglycemia, likely disrupts hypothalamo-pituitary-adrenal (HPA) control, further dysregulating glucose homeostasis. OBJECTIVE To test the hypothesis that endogenous adrenocorticotropic hormone (ACTH)-cortisol dose-responsive drive, estimated analytically, is significantly accentuated in adolescents and young adults with T1DM compared with healthy individuals. DESIGN, SETTING, PATIENTS, AND INTERVENTIONS This was a pilot study of 11 volunteers with T1DM and 10 controls, ages 16-30 yr, at a medical center. Subjects underwent overnight frequent blood sampling (every 10 min for ACTH and cortisol and every 60 min for blood glucose) from 10 pm to 8 am. T1DM volunteers maintained their home insulin regimen. MAIN OUTCOMES Deconvolution analysis and dose-response estimates were the key outcomes. RESULTS Mean free cortisol, but not ACTH, concentrations were lower in the T1DM group compared with controls (p = 0.012). Non-invasive ACTH-cortisol dose-response estimates revealed that T1DM patients had reduced ACTH efficacy (maximal cortisol secretion, p = 0.009), reduced ACTH potency as quantified by greater EC50 (ACTH concentration driving half-maximal cortisol secretion, p = 0.04), and increased ACTH sensitivity (more positive ACTH-cortisol slope, p = 0.03). Post-hoc gender comparisons indicated that these differences were limited to females. Linear regression in women showed a strong correlation of both ACTH efficacy and EC50 with C-peptide levels (both p < 0.01). CONCLUSION Compared with healthy individuals, T1DM patients manifest decreased overnight adrenal responsiveness to endogenous ACTH leading to lower free cortisol concentrations. These findings suggest impaired stress-related adaptations of the HPA axis in T1DM.
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Affiliation(s)
- Animesh N. Sharma
- Children's Hospital Central California, 9300 Valley Children's Place, Madera, CA 93636-8762, Tel: (559) 353-3000,Endocrine Research Unit, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, Tel: (507) 255-0902; Fax: (507) 255-0901
| | - Jean Wigham
- Endocrine Research Unit, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, Tel: (507) 255-0902; Fax: (507) 255-0901
| | - Johannes D. Veldhuis
- Endocrine Research Unit, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, Tel: (507) 255-0902; Fax: (507) 255-0901,Corresponding author: Johannes D. Veldhuis M.D., , Address: Endocrine Research Unit, Center for Translational Science Activities, Mayo, Clinic, 200 1 Street SW, Rochester, MN 55905, Telephone: (507) 255-0902, Facsimile: (507) 255-0901
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Boonen E, Meersseman P, Vervenne H, Meyfroidt G, Guïza F, Wouters PJ, Veldhuis JD, Van den Berghe G. Reduced nocturnal ACTH-driven cortisol secretion during critical illness. Am J Physiol Endocrinol Metab 2014; 306:E883-92. [PMID: 24569590 PMCID: PMC3989736 DOI: 10.1152/ajpendo.00009.2014] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recently, during critical illness, cortisol metabolism was found to be reduced. We hypothesize that such reduced cortisol breakdown may suppress pulsatile ACTH and cortisol secretion via feedback inhibition. To test this hypothesis, nocturnal ACTH and cortisol secretory profiles were constructed by deconvolution analysis from plasma concentration time series in 40 matched critically ill patients and eight healthy controls, excluding diseases or drugs that affect the hypothalamic-pituitary-adrenal axis. Blood was sampled every 10 min between 2100 and 0600 to quantify plasma concentrations of ACTH and (free) cortisol. Approximate entropy, an estimation of process irregularity, cross-approximate entropy, a measure of ACTH-cortisol asynchrony, and ACTH-cortisol dose-response relationships were calculated. Total and free plasma cortisol concentrations were higher at all times in patients than in controls (all P < 0.04). Pulsatile cortisol secretion was 54% lower in patients than in controls (P = 0.005), explained by reduced cortisol burst mass (P = 0.03), whereas cortisol pulse frequency (P = 0.35) and nonpulsatile cortisol secretion (P = 0.80) were unaltered. Pulsatile ACTH secretion was 31% lower in patients than in controls (P = 0.03), again explained by a lower ACTH burst mass (P = 0.02), whereas ACTH pulse frequency (P = 0.50) and nonpulsatile ACTH secretion (P = 0.80) were unchanged. ACTH-cortisol dose response estimates were similar in patients and controls. ACTH and cortisol approximate entropy were higher in patients (P ≤ 0.03), as was ACTH-cortisol cross-approximate entropy (P ≤ 0.001). We conclude that hypercortisolism during critical illness coincided with suppressed pulsatile ACTH and cortisol secretion and a normal ACTH-cortisol dose response. Increased irregularity and asynchrony of the ACTH and cortisol time series supported non-ACTH-dependent mechanisms driving hypercortisolism during critical illness.
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Affiliation(s)
- Eva Boonen
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, and
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Roelfsema F, Pijl H, Keenan DM, Veldhuis JD. Diminished adrenal sensitivity and ACTH efficacy in obese premenopausal women. Eur J Endocrinol 2012; 167:633-42. [PMID: 22909443 DOI: 10.1530/eje-12-0592] [Citation(s) in RCA: 14] [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: 11/08/2022]
Abstract
BACKGROUND The ACTH-cortisol axis in women is activated and associated with decreased ACTH potency, estimated by relating ACTH and cortisol pulse masses. Recently, a new accurate method for constructing the endogenous dose-response relationship was introduced, which is based on the relation between ACTH concentrations and associated cortisol secretion rates within cortisol bursts. HYPOTHESIS The endogenous dose-response relation between ACTH and cortisol in obesity is changed, leading to diminished responsiveness. SUBJECTS Twenty-five obese premenopausal women and 16 normal weight premenopausal women were studied by 10-min blood sampling for 24 h. OUTCOMES ACTH and cortisol secretion rates, analytical dose-response estimates of endogenous ACTH efficacy (maximal cortisol secretion), dynamic ACTH potency, and adrenal sensitivity (slope term) from 24-h ACTH-cortisol profiles were quantified. RESULTS The initial potency (negative logarithm) was -7.83 ± 0.75 (mean ± s.e.m.) in obese women and -10.14 ± 1.08 in lean women (P=0.10), and the corresponding values for the recovery phase were -26.62 ± 2.21 and -36.67 ± 1.66 (P=0.004). The sensitivity (curve slope) amounted to 0.468 ± 0.05 in obese women and 0.784 ± 0.09 in normal weight women (P=0.004). The efficacy (maximal value) was 17.6 ± 4.9 nmol/l per min in obese women and 26.3 ± 3.8 nmol/l per min in normal weight women (P=0.009). Basal secretion rate, inflection point, and EC(50) values were not different. Bromocriptine or acipimox did not change the dose-response curve. CONCLUSION The ACTH-cortisol relation in obesity in women is characterized by decreased sensitivity and efficacy, thus explaining non-elevated serum cortisol concentrations despite increased plasma ACTH levels.
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Affiliation(s)
- Ferdinand Roelfsema
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, The Netherlands.
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Veldhuis JD, Liu PY, Takahashi PY, Keenan DM. Dynamic testosterone responses to near-physiological LH pulses are determined by the time pattern of prior intravenous LH infusion. Am J Physiol Endocrinol Metab 2012; 303:E720-8. [PMID: 22811471 PMCID: PMC3468430 DOI: 10.1152/ajpendo.00200.2012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The long-lived glycoprotein hormone, human chorionic gonadotropin (hCG), downregulates testosterone (T) biosynthesis in vitro and in vivo in animals and humans. The degree to which short-lived pulses of pituitary luteinizing hormone (LH) do so, particularly at physiological concentrations, is not known. We test the hypothesis that continuous LH infusion compared with bolus injections of LH every 1 h or every 2 h overnight downregulates T secretory responses to a subsequent fixed template of three consecutive intravenous pulses of a physiological amount of recombinant human (rh) LH (triple stimulus). Nineteen healthy men ages 18-49 yr each underwent four separate randomly ordered overnight gonadotropin-releasing hormone-receptor antagonist treatments with superimposed intravenous infusions of saline or rhLH (1-h pulses, 2-h pulses, or continuously). Each 12-h infusion protocol was followed by the triple rhLH-pulse stimulus the next morning. During the triple stimulus, basal (nonpulsatile) as well as total (basal plus pulsatile) T secretion was higher after overnight 2- and 1-h rhLH pulses than after continuous rhLH or saline delivery. Approximate entropy, a probabilistic measure of feedforward-induced irregularity of T concentration time series, was higher after 1-h rhLH pulses than after continuous rhLH. Analytical estimation of pulsatile rhLH-T dose-response measures revealed higher T secretory sensitivity and greater rhLH potency (lower EC₅₀) after exposure to 1-h than 2-h rhLH pulses. Collectively, these data indicate that in vivo dynamics of LH-stimulated T secretion under standardized conditions in men depend on the prior time mode of LH delivery in the bloodstream.
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Affiliation(s)
- Johannes D Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN, USA.
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11
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Vis DJ, Westerhuis JA, Hoefsloot HCJ, Roelfsema F, Hendriks MMWB, Smilde AK. Detecting regulatory mechanisms in endocrine time series measurements. PLoS One 2012; 7:e32985. [PMID: 22461889 PMCID: PMC3312884 DOI: 10.1371/journal.pone.0032985] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 02/06/2012] [Indexed: 11/19/2022] Open
Abstract
The regulatory mechanisms underlying pulsatile secretion are complex, especially as it is partly controlled by other hormones and the combined action of multiple agents. Regulatory relations between hormones are not directly observable but may be deduced from time series measurements of plasma hormone concentrations. Variation in plasma hormone levels are the resultant of secretion and clearance from the circulation. A strategy is proposed to extract inhibition, activation, thresholds and circadian synchronicity from concentration data, using particular association methods. Time delayed associations between hormone concentrations and/or extracted secretion pulse profiles reveal the information on regulatory mechanisms. The above mentioned regulatory mechanisms are illustrated with simulated data. Additionally, data from a lean cohort of healthy control subjects is used to illustrate activation (ACTH and cortisol) and circadian synchronicity (ACTH and TSH) in real data. The simulation and the real data both consist of 145 equidistant samples per individual, matching a 24-hr time span with 10 minute intervals. The results of the simulation and the real data are in concordance.
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Affiliation(s)
- Daniel J Vis
- Department of Metabolic Diseases, University Medical Center Utrecht, Utrecht, The Netherlands.
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Veldhuis JD, Liu PY, Keenan DM, Takahashi PY. Older men exhibit reduced efficacy of and heightened potency downregulation by intravenous pulses of recombinant human LH: a study in 92 healthy men. Am J Physiol Endocrinol Metab 2012; 302:E117-22. [PMID: 21971523 PMCID: PMC3328086 DOI: 10.1152/ajpendo.00450.2011] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Direct sampling of the human spermatic veins has disclosed concomitant LH and testosterone (T) pulses, suggesting pulsatile LH concentration-dependent stimulation of T secretion. However, studies to date have examined this hypothesis using only pharmacological stimulation with hCG. The present study tests the hypothesis that age is marked by decreased T secretory responses to repeated near-physiological iv pulses of recombinant human LH administered in a Clinical Translational Science Center. Participants included 92 healthy men aged 18-75 yr with BMI 18-34 kg/m(2). The contribution of endogenous LH pulses was minimized by combined injection of a selective GnRH receptor antagonist sc and successive pulses of biosynthetic LH iv. A new analytical dose response model was applied to estimate the properties of exogenous LH's drive of T secretion. Regression of LH-T dose response potency estimates on age showed that the efficacy of pulses of biosynthetic LH progressively decreased with age (P = 0.014, r = 0.26). Testis sensitivity to exogenous LH pulses also declined with age (P = 0.011, r = 0.27). Moreover, estimated Leydig cell downregulation by LH pulses rose significantly with age (P = 0.039, r = 0.22). These outcomes were selective, since the recovery potency of infused LH was not affected by age but was reduced by increasing BMI (P = 0.011, r = 0.27). Assuming stable bioactivity of infused recombinant human LH, these novel data indicate that factors associated with age and BMI attenuate LH efficacy and testis sensitivity and augment Leydig cell downregulation in healthy men.
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Affiliation(s)
- Johannes D Veldhuis
- Endocrine Research Unit, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA.
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Roelfsema F, Keenan DM, Veldhuis JD. Endogenous ACTH concentration-cortisol secretion dose analysis unmasks decreased ACTH potency in Cushing's disease with restoration after successful pituitary adenomectomy. J Clin Endocrinol Metab 2011; 96:3768-74. [PMID: 21917875 PMCID: PMC3410358 DOI: 10.1210/jc.2011-1878] [Citation(s) in RCA: 9] [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 The relationship between circulating ACTH levels and cortisol secretion in Cushing's disease is not precisely known. HYPOTHESIS Chronic ACTH hyperstimulation leads to decreased adrenal potency and is restored after normalization of ACTH secretion. SUBJECTS Subjects included 20 patients with Cushing's disease, eight patients in long-term remission, and 36 healthy controls. OUTCOMES ACTH and cortisol secretion rates and analytical dose-response estimates of endogenous ACTH efficacy (maximal cortisol secretion), dynamic ACTH potency, and adrenal sensitivity (slope term) from 24-h ACTH-cortisol profiles were evaluated. RESULTS Both basal and pulsatile secretion of ACTH and cortisol were increased in patients with active disease but normal in cured patients. ACTH, but not cortisol pulse frequency, was amplified in patients and restored after successful surgical treatment. ACTH EC(50), an inverse measure of potency, was higher during pulse onset in Cushing's disease (59 ± 7.4 ng/liter) than in controls (20 ± 3.7 ng/liter) (P < 0.0001) and remitted patients after surgery [15 ± 3.2 ng/liter, P value not significant (NS) vs. controls] and during pulse recovery phases [128 ± 18 (P <0.0001), 70 ± 8.4, and 67 ± 17 ng/liter (NS vs. controls), respectively]. Efficacy was increased in active disease and normalized after surgical treatment [patients, 38 ± 8.3 nmol/liter · min, vs. controls, 21 ± 2.3 nmol/liter · min (P <0.0001), and cured patients, 15 ± 3.2 nmol/liter · min (NS vs. controls)]. Sensitivity to endogenous ACTH did not differ among the three groups. CONCLUSION The adrenal gland in Cushing's disease exhibits decreased responsiveness to submaximal ACTH drive and amplified efficacy, with unchanged sensitivity. These target-gland abnormalities are reversible in long-term remission after pituitary surgery.
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Affiliation(s)
- Ferdinand Roelfsema
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands.
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Iranmanesh A, Keenan DM, Aoun P, Veldhuis JD. Overnight ACTH-cortisol dose responsiveness: comparison with 24-h data, metyrapone administration and insulin-tolerance test in healthy adults. Clin Endocrinol (Oxf) 2011; 75:596-601. [PMID: 21609353 PMCID: PMC3287347 DOI: 10.1111/j.1365-2265.2011.04125.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE To estimate the dose dependence of endogenous ACTH stimulation of adrenal cortisol secretion overnight. DESIGN Ten-minute sampling for ACTH and cortisol over 8 and 24 h (n = 17), after metyrapone administration (n = 6), during an insulin-tolerance test (n = 7). SUBJECTS Healthy adults. MEASUREMENTS ACTH dose-responsive estimates. RESULTS Twenty-four hour ACTH-cortisol concentration pairs yielded an estimated EC(50) (one-half maximally stimulatory ACTH concentration) of 5·1 (2·2-9·5) pmol/l [median (range)]. This did not differ from EC(50) s based on 8- or 6-h data [5·9 (3·5-11) and 7·5 (3·7-41) pmol/l] in the same individuals. ACTH efficacy (maximally stimulatable cortisol secretion rate) was 8·4 (3·1-20), 11 (5·9-24) and 15 (5·9-22) nmol/l/min, when calculated over 24, 8 and 6 h, respectively (P = NS). Adrenal sensitivity (slope term) was also consistent across sampling durations, viz. 14 (1·3-95), 18 (1·3-64) and 20 (1·3-64) slope units. Compared with placebo, metyrapone reduced ACTH efficacy from 11 (6·2-62) to 2·8 (1·5-4·5) nmol/l/min for cortisol (n = 9, P < 0·001), while increasing ACTH efficacy for 11-desoxycortisol from 2·3 (0·9-2·9) to 99 (70-218) nmol/l/min (n = 6, P < 0·01), thus affirming face validity. Combined ACTH and cortisol responses to hypoglycaemia allowed an estimate of ACTH efficacy of 28 (22-81) nmol/l/min, compared with the control value of 8·7 (5·6-26), suggesting enhanced adrenal responsiveness. CONCLUSIONS The results suggest that endogenous ACTH-adrenal drive can be approximated from overnight 8-h sampling of paired ACTH and cortisol concentrations. This strategy may have merit in clinical research in childhood, pregnancy, anxiety states and frail elderly individuals, when ACTH injections are not desired.
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Affiliation(s)
- Ali Iranmanesh
- Endocrine Section, Department of Medicine, Salem Veterans Affairs Medical Center, Salem, VA 24153
| | - Daniel M. Keenan
- Department of Statistics, University of Virginia, Charlottesville, VA 22904
| | - Paul Aoun
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905
| | - Johannes D. Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905
- Corresponding author: Tel: (507) 255-0902, Tel: (507) 255-0901,
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Veldhuis JD, Iranmanesh A, Roelfsema F, Aoun P, Takahashi P, Miles JM, Keenan DM. Tripartite control of dynamic ACTH-cortisol dose responsiveness by age, body mass index, and gender in 111 healthy adults. J Clin Endocrinol Metab 2011; 96:2874-81. [PMID: 21752885 PMCID: PMC3167672 DOI: 10.1210/jc.2011-0084] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Recent analyses in small cohorts suggest that pituitary hormones exert time-varying (viz., initial and delayed) dynamic dose-responsive effects on target glands, wherein down-regulating dynamics are inferable on a time scale of single pulses. HYPOTHESIS Age, body mass index (BMI), and sex modulate the rapid potency-down-regulating dynamics of pulsatile pituitary ACTH-adrenal cortisol coupling overnight. LOCATION The study was conducted at a clinical translational research unit. SUBJECTS Subjects included healthy adults (48 women, 63 men; aged 18-77 yr; BMI 18-42 kg/m(2)). OUTCOMES Outcomes included analytical dose-response estimates of endogenous ACTH efficacy, dynamic ACTH potency, and adrenal sensitivity from overnight 10-min ACTH-cortisol profiles. RESULTS Stepwise backward-elimination, multivariate-regression analysis revealed that in the combined cohorts (n = 111), age was associated with enhanced initial ACTH potency (R = 0.265, P = 0.005). Moreover, age and BMI jointly attenuated adrenal sensitivity (R = 0.334, P = 0.0017) and augmented down-regulated ACTH potency (R = 0.321 and P = 0.0028). Exploratory gender-segmented analyses showed that these outcomes might be explained by: (1) a negative effect of age in men on adrenal sensitivity (R = 0.270, P = 0.034) and (2) positive effects of age in men (R = 0.332, P = 0.0019) and BMI in women (R = 0.331, P = 0.024) on initial ACTH potency. CONCLUSIONS In healthy adults, adrenal sensitivity to endogenous ACTH pulses, ACTH efficacy, and ACTH potency is associated with age, BMI, and gender. These findings may explain conflicting data in earlier literature and introduce the need to control all three of age, BMI, and sex in future studies of the stress-adaptive axis.
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Affiliation(s)
- Johannes D Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA.
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Iranmanesh A, Lawson D, Dunn B, Veldhuis JD. Glucose ingestion selectively amplifies ACTH and cortisol secretory-burst mass and enhances their joint synchrony in healthy men. J Clin Endocrinol Metab 2011; 96:2882-8. [PMID: 21752898 PMCID: PMC3167666 DOI: 10.1210/jc.2011-0682] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
CONTEXT Glucose intake is associated with a variable increase in adrenal glucocorticoid secretion. HYPOTHESIS Glucose ingestion elevates cortisol secretion by 1) augmenting pulsatile ACTH release; and/or 2) enhancing ACTH-cortisol synchrony or dose-responsiveness. SUBJECTS Fifty-eight healthy men ages 19-78 yr with computed tomography-estimated abdominal visceral fat participated in the study. LOCATION The study was conducted at the Clinical Translational-Research Center and Veterans Affairs Medical Center. METHODS We conducted frequent sampling of plasma ACTH and cortisol concentrations after glucose vs. water ingestion in the fasting state, as well as deconvolution, approximate entropy, linear-regression, and dose-response analysis. OUTCOMES After water ingestion, age was a negative correlate of the mass of ACTH (P = 0.009; R(2) = 0.119) and of cortisol (P < 0.001; R(2) = 0.269) secreted per burst. Glucose ingestion abolished both relationships but amplified pulsatile ACTH (P = 0.009) and cortisol (P = 0.001) secretion. Glucose exposure selectively augmented the mass of ACTH (P < 0.001) and of cortisol (P = 0.004) secreted per burst without altering burst number or basal secretion. The increment in pulsatile ACTH strongly predicted the increment in pulsatile cortisol (P < 10(-4); R(2) = 0.325) secretion. Abdominal visceral fat positively forecast the glucose-induced increment in cortisol secretory-burst mass (P = 0.019). According to approximate entropy analysis, glucose input also enhanced the joint synchrony of ACTH-cortisol secretory patterns (P ≤ 0.001). Caloric intake did not affect analytical dose-response estimates of ACTH potency and efficacy or adrenal sensitivity. CONCLUSION Conjoint augmentation of the mass of ACTH and cortisol secreted per burst and enhancement of ACTH-cortisol synchrony underlie glucose-induced glucocorticoid secretion in healthy men. Visceral adiposity is a predictor of the glucose-stimulated increment in burst-like cortisol output, suggesting an additional possible mechanism for increased cardiovascular risk in abdominal obesity.
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Affiliation(s)
- Ali Iranmanesh
- Endocrine Section, Medical Service, Salem Veterans Affairs Medical Center, Salem, Virginia 24153, USA
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Keenan DM, Iranmanesh A, Veldhuis JD. Analytical construct of reversible desensitization of pituitary-testicular signaling: illustrative application in aging. Am J Physiol Regul Integr Comp Physiol 2010; 300:R349-60. [PMID: 21084679 DOI: 10.1152/ajpregu.00477.2010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Luteinizing hormone (LH) administered in pharmacological amounts downregulates Leydig cell steroidogenesis. Whether reversible downregulation of physiological gonadotropin drive operates in vivo is unknown. Most of the analytical models of dose-response functions that have been constructed are biased by the assumption that no downregulation exists. The present study employs a new analytical platform to quantify potential (but not required) pulsatile cycles of LH-testosterone (T) dose-response stimulation, desensitization, and recovery (pulse-by-pulse hysteresis) in 26 healthy men sampled every 10 min for 24 h. A sensitivity-downregulation hysteresis construct predicted marked hysteresis with a median time delay to LH dose-response inflection within individual T pulses of 23 min and with median T pulse onset and recovery LH sensitivities of 1.1 and 0.10 slope unit, respectively (P < 0.001). A potency-downregulation model yielded median estimates of one-half maximally stimulatory LH concentrations (EC(50) values) of 0.66 and 7.5 IU/l for onset and recovery, respectively (P < 0.001). An efficacy-downregulation formulation of hysteresis forecasts median LH efficacies of 20 and 8.3 ng·dl(-1)·min(-1) for onset and offset of T secretory burst, respectively (P = 0.002). Segmentation of the LH-T data by age suggested greater sensitivity, higher EC(50) (increased LH potency), and markedly (2.7-fold) attenuated LH efficacy in older individuals. Each of the three hysteresis models yielded a marked (P < 0.005) reduction in estimated model residual error compared with no hysteresis. In summary, model-based analyses allowing for (but not requiring) reversible pituitary-gonadal effector-response downregulation are consistent with a hypothesis of recurrent, brief cycles of LH-dependent stimulation, desensitization, and recovery of pulsatile T secretion in vivo and an age-associated reduction of LH efficacy. Prospective studies would be required to prove this aging effect.
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Affiliation(s)
- Daniel M Keenan
- Department of Statistics, University of Virginia, Charlottesville, USA
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