1
|
Liu PY, Lawrence-Sidebottom D, Piotrowska K, Zhang W, Iranmanesh A, Auchus RJ, Veldhuis JD, Van Dongen HPA. Clamping Cortisol and Testosterone Mitigates the Development of Insulin Resistance during Sleep Restriction in Men. J Clin Endocrinol Metab 2021; 106:e3436-e3448. [PMID: 34043794 PMCID: PMC8660069 DOI: 10.1210/clinem/dgab375] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Indexed: 01/04/2023]
Abstract
CONTEXT Sleep loss in men increases cortisol and decreases testosterone, and sleep restriction by 3 to 4 hours/night induces insulin resistance. OBJECTIVE We clamped cortisol and testosterone and determined the effect on insulin resistance. METHODS This was a randomized double-blind, in-laboratory crossover study in which 34 healthy young men underwent 4 nights of sleep restriction of 4 hours/night under 2 treatment conditions in random order: dual hormone clamp (cortisol and testosterone fixed), or matching placebo (cortisol and testosterone not fixed). Fasting blood samples, and an additional 23 samples for a 3-hour oral glucose tolerance test (OGTT), were collected before and after sleep restriction under both treatment conditions. Cytokines and hormones were measured from the fasting samples. Overall insulin sensitivity was determined from the OGTT by combining complementary measures: homeostasis model assessment of insulin resistance of the fasting state; Matsuda index of the absorptive state; and minimal model of both fasting and absorptive states. RESULTS Sleep restriction alone induced hyperinsulinemia, hyperglycemia, and overall insulin resistance (P < 0.001 for each). Clamping cortisol and testosterone alleviated the development of overall insulin resistance (P = 0.046) and hyperinsulinemia (P = 0.014) by 50%. Interleukin-6, high-sensitivity C-reactive protein, peptide YY, and ghrelin did not change, whereas tumor necrosis factor-α and leptin changed in directions that would have mitigated insulin resistance with sleep restriction alone. CONCLUSION Fixing cortisol-testosterone exposure mitigates the development of insulin resistance and hyperinsulinemia, but not hyperglycemia, from sustained sleep restriction in men. The interplay between cortisol and testosterone may be important as a mechanism by which sleep restriction impairs metabolic health.
Collapse
Affiliation(s)
- Peter Y Liu
- Division of Endocrinology, The Lundquist Institute at Harbor UCLA Medical Center, Torrance, CA, USA
- David Geffen School of Medicine, University of California—Los Angeles, Los Angeles, CA, USA
| | - Darian Lawrence-Sidebottom
- Sleep and Performance Research Center, Washington State University, Spokane, WA, USA
- Neuroscience Graduate Program, Washington State University, Pullman, WA, USA
| | - Katarzyna Piotrowska
- Division of Endocrinology, The Lundquist Institute at Harbor UCLA Medical Center, Torrance, CA, USA
| | - Wenyi Zhang
- Division of Endocrinology, The Lundquist Institute at Harbor UCLA Medical Center, Torrance, CA, USA
| | - Ali Iranmanesh
- Endocrinology Service, VA Medical Center, Salem, VA, USA
| | - Richard J Auchus
- Division of Metabolism, Diabetes, and Endocrinology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - Johannes D Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN, USA
| | - Hans P A Van Dongen
- Sleep and Performance Research Center, Washington State University, Spokane, WA, USA
- Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, USA
| |
Collapse
|
2
|
Roelfsema F, Liu PY, Yang R, Takahashi P, Veldhuis JD. Interleukin-2 drives cortisol secretion in an age-, dose-, and body composition-dependent way. Endocr Connect 2020; 9:637-648. [PMID: 32520721 PMCID: PMC7424344 DOI: 10.1530/ec-20-0211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 06/08/2020] [Indexed: 01/21/2023]
Abstract
BACKGROUND Interleukin-2 (IL-2), one of the proinflammatory cytokines, is used in the treatment of certain malignancies. In some studies, transient increases in cortisol and ACTH secretion occurred. Thus, this agent may be used as an experimental probe of adrenal cortisol secretion. OBJECTIVE This study quantifies the effects of low and moderate doses of IL-2 on cortisol secretion and assesses the modulation by age, dose and body composition. SITE Mayo Clinical Translational Research Unit. SUBJECTS Study comprised 35 healthy men, 17 young and 18 older. METHODS Randomized prospective double-blind saline-controlled study of IL-2 administration in two doses with concurrent 10-min blood sampling for 24 h. OUTCOME MEASURES Deconvolution analysis and approximate entropy of cortisol secretion. RESULTS Low-dose IL-2 administration increased nocturnal pulsatile cortisol secretion from 1460 ± 160 to 2120 ± 220 nmol/L/8 h in young subjects and from 1680 ± 105 to 1960 ± 125 nmol/L/8 h (treatment P < 0.0001, but more in young than older, P = 0.02). Comparable results were obtained for total cortisol secretion (P treatment <0.0001, age effect P = 0.005). The higher IL-2 dose caused a large increase in young (P < 0.0001), but not in older (P = 0.90) subjects. This dose also increased approximate entropy from 0.877 ± 0.041 to 1.024 ± 0.049 (P = 0.008), pointing to reduced secretory orderliness. Incremental cortisol (nocturnal) secretion correlated negatively with visceral fat mass (R = -0.41, P = 0.019). CONCLUSION In healthy men, IL-2 injection drives pulsatile cortisol secretion in a dose-dependent way in young, but not older, individuals and erodes cortisol secretory orderliness at a higher dose in young subjects. Cortisol responses are diminished with increasing abdominal visceral fat mass.
Collapse
Affiliation(s)
- Ferdinand Roelfsema
- Department of Internal Medicine, Section Endocrinology, 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, USA
| | - Rebecca Yang
- Endocrine Research Unit, Mayo Clinic College of Medicine, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota, USA
| | - Paul Takahashi
- Primary Care Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Johannes D Veldhuis
- Endocrine Research Unit, Mayo Clinic College of Medicine, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota, USA
- Correspondence should be addressed to J D Veldhuis:
| |
Collapse
|
3
|
Roelfsema F, Yang RJ, Olson TP, Joyner MJ, Takahashi PY, Veldhuis JD. Enhanced Coupling Within Gonadotropic and Adrenocorticotropic Axes by Moderate Exercise in Healthy Men. J Clin Endocrinol Metab 2017; 102:2482-2490. [PMID: 28453740 PMCID: PMC5505190 DOI: 10.1210/jc.2017-00036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 04/17/2017] [Indexed: 11/19/2022]
Abstract
CONTEXT Exercise elicits incompletely defined adaptations of metabolic and endocrine milieu, including the gonadotropic and corticotropic axes. OBJECTIVE To quantify the impact of acute exercise on coordinate luteinizing hormone (LH) and testosterone (T) and adrenocorticotropic hormone (ACTH) and cortisol secretion in healthy men in relation to age. PARTICIPANTS AND DESIGN Prospectively randomized, within-subject crossover study in 23 men aged 19 to 77 years old. Subjects underwent rest and 30 minutes of mixed exercise at 65% of maximal aerobic capacity with 10-minute blood sampling between 7:00 am and 1:00 pm, 2 weeks apart. MAIN OUTCOME MEASURES Incremental changes in LH, T, ACTH, and cortisol concentrations, the feedforward and feedback strength between exercise and rest, quantified by approximate entropy (ApEn), and bihormonal synchrony, quantitated by cross-ApEn. RESULTS Mean hourly exercise-minus-rest LH and ACTH increments increased from -0.055 ± 0.187 to 0.755 ± 0.245 IU/L (P = 0.003) and from 2.9 ± 2.2 to 71.2 ± 16.1 ng/L (P < 0.0001), respectively, during exercise. T and cortisol increments increased concurrently from -9.6 ± 16.7 to 47.6 ± 17.1 ng/dL (P < 0.0001) and 0.45 ± 0.76 to 7.27 ± 0.64 µg/dL (P < 0.0001), respectively. During exercise, feedforward and feedback LH-T and ACTH-cortisol cross-ApEn decreased markedly quantifying enhanced hormonal coupling. CONCLUSIONS Acute moderate mixed exercise in healthy men rapidly enhances feedforward LH-T and ACTH-cortisol coordination and reciprocal feedback within the gonadotropic and corticotropic axes. In principle, enhancement of both LH-T and ACTH-cortisol secretory synchrony by exercise could reflect augmented coupling between brain-testicular and brain-adrenal neural outflow.
Collapse
Affiliation(s)
- Ferdinand Roelfsema
- Department of Endocrinology and Metabolism, Leiden University Medical Center, 2333ZA Leiden, The Netherlands
| | - Rebecca J. Yang
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905
| | - Thomas P. Olson
- Department of Cardiovascular Research, Mayo Clinic, Rochester, Minnesota 55905
| | - Michael J. Joyner
- Department of Anesthesia Research, Department of Physiology and Biomedical Engineering, and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55905
| | - Paul Y. Takahashi
- Department of Primary Care Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905
| | - Johannes D. Veldhuis
- Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905
| |
Collapse
|
4
|
Roelfsema F, Aoun P, Veldhuis JD. Pulsatile Cortisol Feedback on ACTH Secretion Is Mediated by the Glucocorticoid Receptor and Modulated by Gender. J Clin Endocrinol Metab 2016; 101:4094-4102. [PMID: 27548106 PMCID: PMC5095237 DOI: 10.1210/jc.2016-2405] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
CONTEXT Factors that regulate physiological feedback by pulses of glucocorticoids on the hypothalamic-pituitary unit are sparsely defined in humans in relation to gluco- or mineralocorticoid receptor pathways, gender, age, and the sex steroid milieu. OBJECTIVE The objective of the study was to test (the clinical hypothesis) that glucocorticoid (GR) and mineralocorticoid (MR) receptor-selective mechanisms differentially govern pulsatile cortisol-dependent negative feedback on ACTH output (by the hypothalamo-pituitary unit) in men and women studied under experimentally defined T and estradiol depletion and repletion, respectively. SETTING The study was conducted at the Mayo Center for Translational Science Activities. SUBJECTS Healthy middle-aged men (n = 16) and women (n = 25) participated in the study. INTERVENTIONS This was a randomized, prospective, double-blind, placebo- and saline-controlled study of pulsatile cortisol infusions in low cortisol-clamped volunteers with and without eplerenone (MR blocker) and mifepristone (GR blocker) administration under a low and normal T and estradiol clamp. During frequent sampling, a bolus of CRH-arginine vasopressin was infused to assess corticotrope responsiveness. Analytical Methods and Outcomes: Deconvolution and approximate entropy of ACTH profiles were measured. RESULTS Infusion of cortisol (but not saline) pulses diminished ACTH secretion. The GR antagonist, mifepristone, interfered with negative feedback on both ACTH burst mass and secretion regularity. Eplerenone, an MR antagonist, exerted no detectable effect on the same parameters. Despite feedback imposition, CRH-arginine vasopressin-stimulated ACTH secretion was also increased by mifepristone and not by eplerenone. Withdrawal vs addback of sex steroids had no effect on ACTH secretion parameters. Nonetheless, ACTH secretion was greater (P = .006) and more regular (P = .004) in men than women. CONCLUSION Pulsatile cortisol feedback on ACTH secretion in this paradigm is mediated by the glucocorticoid receptor, in part acting at the level of the pituitary, and influenced by sex.
Collapse
Affiliation(s)
- Ferdinand Roelfsema
- Department of Endocrinology and Metabolism (F.R.), Leiden University Medical Center, 2300 RC Leiden, The Netherlands; and Endocrine Research Unit (P.A., J.D.V.), Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905
| | - Paul Aoun
- Department of Endocrinology and Metabolism (F.R.), Leiden University Medical Center, 2300 RC Leiden, The Netherlands; and Endocrine Research Unit (P.A., J.D.V.), Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905
| | - Johannes D Veldhuis
- Department of Endocrinology and Metabolism (F.R.), Leiden University Medical Center, 2300 RC Leiden, The Netherlands; and Endocrine Research Unit (P.A., J.D.V.), Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905
| |
Collapse
|
5
|
Roelfsema F, Pereira AM, Veldhuis JD. Impact of Adiposity and Fat Distribution on the Dynamics of Adrenocorticotropin and Cortisol Rhythms. Curr Obes Rep 2014; 3:387-95. [PMID: 26626915 DOI: 10.1007/s13679-014-0118-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Obesity impacts many hormonal systems, including pituitary hormones, as well as insulin and leptin. In this review we discuss articles which investigate the influence of obesity on the hypothalamic-pituitary-adrenal (HPA) axis. Different techniques have been used to assess the function of the HPA-axis in obesity, including measuring fasting and/or late evening levels of adrenocorticotropic hormone (ACTH) and (free) cortisol in plasma and saliva, studying feedback with dexamethasone or cortisol, and evaluating responsiveness of the system to corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) or ACTH 1-29. In addition, more elaborate studies investigated 24-h secretion patterns, analyzed with deconvolution techniques to quantitate pulsatile secretion rates of cortisol and less often ACTH. Other investigators used timed infusions of labeled cortisol for the estimation of the 24-h secretion rate, clearance rate and distribution volume. Many studies relied on the 24-h urinary excretion of free cortisol, but for quantitation of the 24-h secretion, measurement of all cortisol-derived metabolites is required. Several studies have applied modern liquid chromatography-tandem-mass spectrometry techniques to measure these metabolites. The picture emerging from all these studies is that, first, ACTH secretion is amplified, likely via enhanced forward drive; and, second, serum cortisol levels are normal or even low, associated with a normal 24-h cortisol secretion per liter distribution volume determined by deconvolution, but enhanced when based on the increased total distribution volume associated with obesity. Increased cortisol secretion was also established by isotope dilution studies and reports based on the measurement of all urinary cortisol metabolites. The responsiveness of the adrenal gland to ACTH is diminished. The studies do not address quantitative aspects of cortisol-cortisone metabolism on individual organs, including liver, central and peripheral fat, intestine, skin, and muscle.
Collapse
Affiliation(s)
- Ferdinand Roelfsema
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Albinusdreef 2, 2333ZA, Leiden, The Netherlands.
| | - Alberto M Pereira
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Albinusdreef 2, 2333ZA, Leiden, The Netherlands
| | - Johannes D Veldhuis
- Endocrine Research Unit, Mayo Medical and Graduate Schools, Clinical Translational Research Center, Mayo Clinic, Rochester, MN, 55901, USA
| |
Collapse
|
6
|
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.
Collapse
Affiliation(s)
- Eva Boonen
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, and
| | | | | | | | | | | | | | | |
Collapse
|
7
|
Animesh S, Paul Aoun DO, Jean Wigham RN, Sue Weist RN, Johannes D. V. Gender determines ACTH recovery from hypercortisolemia in healthy older humans. Metabolism 2013; 62:1819-29. [PMID: 24074810 PMCID: PMC3860097 DOI: 10.1016/j.metabol.2013.08.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Available clinical data raise the possibility that stress-adaptive mechanisms differ by gender. However, this notion has not been rigorously tested in relation to cortisol-mediated negative feedback. MATERIALS/METHODS Degree of ACTH inhibition during and recovery from an experimental cortisol clamp was tested in 20 healthy older subjects (age 60±2.2 y). Volunteers received oral placebo or ketoconazole (KTCZ) to inhibit adrenal steroidogenesis along with i.v. infusions of saline or a low vs high physiological dose of cortisol in a prospectively randomized double-blind, placebo-controlled design. ACTH and cortisol concentrations were measured every 10 min during the feedback-clamp phase and thereafter (recovery or escape phase). Corticosteroid-binding globulin (CBG) was measured, and free cortisol concentrations were calculated. RESULTS Gender did not determine mean ACTH concentrations during the saline or cortisol feedback-clamp phases per se. However, women had markedly impaired ACTH recovery after stopping both low- and high-dose cortisol infusions compared with men (P=0.005, KTCZ/low-dose cortisol arm; and P=0.006, KTCZ/high-dose cortisol arm). Decreased ACTH recovery in women was accompanied by lower total and free cortisol concentrations, pointing to heightened feedback inhibition of hypothalamo-pituitary drive of ACTH secretion as the main mechanism. CONCLUSIONS In summary, gender or a factor related to gender, such as sex steroids or body composition, determines recovery of ACTH secretion from cortisol-enforced negative feedback. Attenuated ACTH recovery in post-menopausal women may have relevance to sex differences in stress-related adaptations.
Collapse
Affiliation(s)
| | | | | | | | - Veldhuis Johannes D.
- Corresponding author. Tel.: + 1 507 255 0902; fax: + 1 507 255 0901. (J.D. Veldhuis)
| |
Collapse
|
8
|
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.
Collapse
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,
| |
Collapse
|
9
|
Leatherland JF, Li M, Barkataki S. Stressors, glucocorticoids and ovarian function in teleosts. JOURNAL OF FISH BIOLOGY 2010; 76:86-111. [PMID: 20738701 DOI: 10.1111/j.1095-8649.2009.02514.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The purpose of this overview is to re-examine the postulated direct and indirect actions of glucocorticoids on ovarian function in teleosts. The re-examination is undertaken in light of recent advances in the understanding of the stress response itself, the mode of action of the hypothalamus-pituitary gland-ovarian (HPO) axis, the mechanisms of control of oestrogen-dependent hepatic vitellogenin (VtG) secretion and the apparent roles of corticotrophin-releasing hormone (CRH) and CRH-related factors in the regulation of feeding activity. Many of the results of different studies, particularly whole-animal studies, are conflicting, and little is known as to whether the hormone acts directly on various components of the HPO axis or indirectly by virtue of redirection of energy resources away from ovarian growth to provide a source of metabolic resources for other organ systems involved in the physiological stress response. In vitro studies provide some new insights into the direct actions of glucocorticoid on hepatic VtG synthesis and ovarian follicle steroidogenesis, but even here, in some studies the cellular sites of action of these hormones is not altogether clear. The overview emphasizes the complexity of the stress response, the complexity of the regulation of glucocorticoid-dependent gene expression and the extensive interactive nature of the HPO with other hypothalamus-pituitary gland-peripheral endocrine gland axes, such as the thyroid (HPT), 'somatic' (GH-IGF) and interrenal tissue (HPI) axes.
Collapse
Affiliation(s)
- J F Leatherland
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
| | | | | |
Collapse
|