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Narinx N, David K, Walravens J, Vermeersch P, Claessens F, Fiers T, Lapauw B, Antonio L, Vanderschueren D. Role of sex hormone-binding globulin in the free hormone hypothesis and the relevance of free testosterone in androgen physiology. Cell Mol Life Sci 2022; 79:543. [PMID: 36205798 DOI: 10.1007/s00018-022-04562-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 08/12/2022] [Accepted: 09/17/2022] [Indexed: 11/03/2022]
Abstract
According to the free hormone hypothesis, biological activity of a certain hormone is best reflected by free rather than total hormone concentrations. A crucial element in this theory is the presence of binding proteins, which function as gatekeepers for steroid action. For testosterone, tissue exposure is governed by a delicate equilibrium between free and total testosterone which is determined through interaction with the binding proteins sex hormone-binding globulin and albumin. Ageing, genetics and various pathological conditions influence this equilibrium, hereby possibly modulating hormonal exposure to the target tissues. Despite ongoing controversy on the subject, strong evidence from recent in vitro, in vivo and human experiments emphasizes the relevance of free testosterone. Currently, however, clinical possibilities for free hormone diagnostics are limited. Direct immunoassays are inaccurate, while gold standard liquid chromatography with tandem mass spectrometry (LC-MS/MS) coupled equilibrium dialysis is not available for clinical routine. Calculation models for free testosterone, despite intrinsic limitations, provide a suitable alternative, of which the Vermeulen calculator is currently the preferred method. Calculated free testosterone is indeed associated with bone health, frailty and other clinical endpoints. Moreover, the added value of free testosterone in the clinical diagnosis of male hypogonadism is clearly evident. In suspected hypogonadal men in whom borderline low total testosterone and/or altered sex hormone-binding globulin levels are detected, the determination of free testosterone avoids under- and overdiagnosis, facilitating adequate prescription of hormonal replacement therapy. As such, free testosterone should be integrated as a standard biochemical parameter, on top of total testosterone, in the diagnostic workflow of male hypogonadism.
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Affiliation(s)
- N Narinx
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Herestraat 49, ON1bis box 902, 3000, Leuven, Belgium.,Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium
| | - K David
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Herestraat 49, ON1bis box 902, 3000, Leuven, Belgium.,Department of Endocrinology, University Hospitals Leuven, Leuven, Belgium
| | - J Walravens
- Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - P Vermeersch
- Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium
| | - F Claessens
- Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - T Fiers
- Department of Laboratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - B Lapauw
- Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium.,Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - L Antonio
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Herestraat 49, ON1bis box 902, 3000, Leuven, Belgium.,Department of Endocrinology, University Hospitals Leuven, Leuven, Belgium
| | - D Vanderschueren
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Herestraat 49, ON1bis box 902, 3000, Leuven, Belgium. .,Department of Endocrinology, University Hospitals Leuven, Leuven, Belgium.
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Choi MH. Clinical and Technical Aspects in Free Cortisol Measurement. Endocrinol Metab (Seoul) 2022; 37:599-607. [PMID: 35982612 PMCID: PMC9449105 DOI: 10.3803/enm.2022.1549] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 07/22/2022] [Accepted: 07/28/2022] [Indexed: 11/11/2022] Open
Abstract
Accurate measurement of cortisol is critical in adrenal insufficiency as it reduces the risk associated with misdiagnosis and supports the optimization of stress dose. Comprehensive assays have been developed to determine the levels of bioactive free cortisol and their clinical and analytical efficacies have been extensively discussed because the level of total cortisol is affected by changes in the structure or circulating levels of corticoid-binding globulin and albumin, which are the main reservoirs of cortisol in the human body. Antibody-based immunoassays are routinely used in clinical laboratories; however, the lack of molecular specificity in cortisol assessment limits their applicability to characterize adrenocortical function. Improved specificity and sensitivity can be achieved by mass spectrometry coupled with chromatographic separation methods, which is a cutting-edge technology to measure individual as well as a panel of steroids in a single analytical run. The purpose of this review is to introduce recent advances in free cortisol measurement from the perspectives of clinical specimens and issues associated with prospective analytical technologies.
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Affiliation(s)
- Man Ho Choi
- Center for Advanced Biomolecular Recognition, Korea Institute of Science and Technology, Seoul, Korea
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3
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The Effect of High-Intensity Exercise on Changes in Salivary and Serum Cortisol Proportion Dynamics. ENDOCRINES 2021. [DOI: 10.3390/endocrines2010005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Typically, salivary cortisol is reported as 5–10% of total cortisol, but the stability of this proportion and the effect of exercise on the 24-h profile is unclear. Therefore, this study investigated the circadian rhythm of the proportion of serum cortisol represented by salivary cortisol, and the impact of acute high-intensity exercise. Recreationally trained males (n = 8, age = 25.7 ± 2.4 years, height = 174.7 ± 7.8 cm, mass = 69.8 ± 12.1 kg) completed two 24-h profiles (rest and exercise conditions) for serum (Q60) and salivary (Q120) cortisol. Exercise consisted of 5 × 30 s sprinting intervals on the cycle ergometer. Cortisol was assessed using commercially available assays. The proportion (Cprop) of serum cortisol (Cser) represented by salivary cortisol (Csal) was calculated as [Cprop = Csal/ Cser × 100]. Multilevel growth models tested for trends across the 24-h profile. The highest relation between Cser and Csal was observed at 08:00 AM (r = 0.90). The average Cprop was 5.95% and demonstrated a circadian profile characterized by a cubic model. Acute exercise did not alter Cser, Csal, or Cprop. Thus, the proportion of Cser represented by Csal changes across a 24-h period and should be accounted for if using salivary cortisol to reflect circadian output of cortisol.
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The plasma protein binding of the endogenous glucocorticosteroids is of vital importance for the concentrations in hair and saliva. Forensic Sci Int 2018; 286:23-30. [PMID: 29547783 DOI: 10.1016/j.forsciint.2018.01.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 12/22/2017] [Accepted: 01/29/2018] [Indexed: 01/13/2023]
Abstract
BACKGROUND The endogenous glucocorticosteroid cortisol (F) and its metabolite cortisone (E) are known to be involved in stress adaption and anti-inflammatory and immune regulatory effects. The ratios of F to E in the matrices serum, hair and saliva are different. The shift of this ratio by the enzyme activity of 11β-hydroxysteroid-dehydrogenase, which inactivates cortisol, was often discussed. The aim of our study was to calculate the contribution of the plasma protein binding (PPB) to this shift. The PPB of F is known to be 96% of the total F-Concentration in serum. The PPB of E was not analyzed in previous studies. METHODS Our study was designed to evaluate the correlation of corticosteroid concentrations in serum (total and free), hair and saliva. The samples were self-collected by the author (A.K.) monthly over a pregnancy cycle (1st samples before pregnancy, 8 samples during pregnancy and 5 samples postpartum). Serum protein binding was calculated from the determination of the total hormone concentrations of F and E (protein bound and unbound) and the free hormone concentrations in serum. The samples were processed by ether extraction and ultrafiltration. Hair samples were extracted with methanol and purified by solid-phase extraction. Saliva samples were collected using Salivette® collection system. The concentrations of F and E were measured by liquid chromatography-mass spectrometry with LODs for free serum, total serum, hair and saliva of F: 0.11ng/mL, 2.13ng/mL, 1.6pg/mg, 0.08ng/mL and E: 0.12ng/mL, 0.54ng/mL, 2.1pg/mg, 0.09ng/mL, respectively. RESULTS AND DISCUSSION The serum concentrations (free and total) of both glucocorticosteroids rise up continuously during the time of pregnancy and decrease after delivery. The free and total serum concentrations were well correlated. No change was detected for the intensity of PPB of F. In contrast, the PPB of E decreases from 86.3% to 80.7% during pregnancy. The concentration ratios of F to E change from 3:1 in total serum to 1:1 in free serum. For hair samples, an increase of F and E in proximal segments was confirmed with the highest concentration 6.5weeks postpartum. Independently, corticosteroid concentrations in corresponding hair segments were found to be reduced with increasing distance from the root; an average decline of F and E by half in 5 and 6months was estimated, respectively. The counter effect of the mechanisms incorporation and wash-out is clearly visible. For saliva samples a good correlation with free, non-protein bound serum concentration was detected.
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Goldman AL, Bhasin S, Wu FCW, Krishna M, Matsumoto AM, Jasuja R. A Reappraisal of Testosterone's Binding in Circulation: Physiological and Clinical Implications. Endocr Rev 2017; 38:302-324. [PMID: 28673039 PMCID: PMC6287254 DOI: 10.1210/er.2017-00025] [Citation(s) in RCA: 213] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 06/23/2017] [Indexed: 02/07/2023]
Abstract
In the circulation, testosterone and other sex hormones are bound to binding proteins, which play an important role in regulating their transport, distribution, metabolism, and biological activity. According to the free hormone hypothesis, which has been debated extensively, only the unbound or free fraction is biologically active in target tissues. Consequently, accurate determination of the partitioning of testosterone between bound and free fractions is central to our understanding of how its delivery to the target tissues and biological activity are regulated and consequently to the diagnosis and treatment of androgen disorders in men and women. Here, we present a historical perspective on the evolution of our understanding of the binding of testosterone to circulating binding proteins. On the basis of an appraisal of the literature as well as experimental data, we show that the assumptions of stoichiometry, binding dynamics, and the affinity of the prevailing models of testosterone binding to sex hormone-binding globulin and human serum albumin are not supported by published experimental data and are most likely inaccurate. This review offers some guiding principles for the application of free testosterone measurements in the diagnosis and treatment of patients with androgen disorders. The growing number of testosterone prescriptions and widely recognized problems with the direct measurement as well as the computation of free testosterone concentrations render this critical review timely and clinically relevant.
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Affiliation(s)
- Anna L Goldman
- Research Program in Men's Health: Aging and Metabolism, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Shalender Bhasin
- Research Program in Men's Health: Aging and Metabolism, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Frederick C W Wu
- Andrology Research Unit, Centre for Endocrinology and Diabetes, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Meenakshi Krishna
- Research Program in Men's Health: Aging and Metabolism, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Alvin M Matsumoto
- Geriatric Research, Education and Clinical Center, VA Puget Sound Health Care System, Seattle, Washington 98108
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, Washington 98104
| | - Ravi Jasuja
- Research Program in Men's Health: Aging and Metabolism, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
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Reyes-Garcés N, Bojko B, Pawliszyn J. High throughput quantification of prohibited substances in plasma using thin film solid phase microextraction. J Chromatogr A 2014; 1374:40-49. [PMID: 25444250 DOI: 10.1016/j.chroma.2014.11.047] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Revised: 11/14/2014] [Accepted: 11/19/2014] [Indexed: 11/25/2022]
Abstract
Simple, fast and efficient sample preparation approaches that allow high-throughput isolation of various compounds from complex matrices are highly desired in bioanalysis. Particularly sought are methods that can, without sacrificing time, easily remove matrix interferences capable of inducing ionization suppression/enhancement, or causing detrimental effects in instrumental performance. In this work, an automated high-throughput sample preparation method using thin film solid phase microextraction (SPME) for the analysis of multiple prohibited substances in plasma is proposed. A biocompatible SPME extraction phase made of hydrophilic-lipophilic balance particles immobilized with polyacrylonitrile (PAN) demonstrated satisfactory extraction capabilities for 25 compounds of a wide range of polarities (logP from -2 to 6.8). Due to the well-known biocompatible characteristics of PAN-based SPME coatings, minimum sample handling was required. Experimental conditions for pre-conditioning, extraction, wash and desorption were carefully optimized for the proposed method. By taking full advantage of the 96 thin film handling capability of the automated system, a preparation time of approximately 1.5min per sample can be achieved. Satisfactory results in terms of absolute matrix effects were found for the majority of the studied analytes, given that 24 out of 25 compounds exhibited values in the range of 100 and 120%. The method was validated in terms of linearity (R(2)>0.99), inter and intra-day accuracy (85-130%) and precision (<20%) and limits of quantitation (0.25-10ngmL(-1) for most compounds).
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Affiliation(s)
| | - Barbara Bojko
- Department of Chemistry, University of Waterloo, Ontario N2L 3G1, Canada
| | - Janusz Pawliszyn
- Department of Chemistry, University of Waterloo, Ontario N2L 3G1, Canada.
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Brossaud J, Gatta B, Tabarin A, Corcuff JB. Different methods to estimate serum free cortisol: a comparison during cortisol tetracosactide testing. Clin Chem Lab Med 2014; 53:1367-73. [PMID: 25381955 DOI: 10.1515/cclm-2014-0912] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 10/20/2014] [Indexed: 11/15/2022]
Abstract
BACKGROUND Serum cortisol is routinely quantified by immunoassays. In intensive care units serum free cortisol (FC) determination has been described as a better indicator of survival than total cortisol (TC). To estimate FC different methods are available including saliva sampling. We compared five methods to estimate FC, before and after an ACTH stimulating test in patients suspected of adrenal insufficiency. METHOD Serum and saliva was collected from 130 patients from the Endocrine Department of a university hospital before and after tetracosactide injection for TC determination. FC was estimated: after serum ultrafiltration, quadratic (Coolens') or cubic (Dorin's) equations, using TC/cortisol-binding globulin concentrations ratio or using cortisol concentration determination in saliva. RESULTS FC concentrations obtained by different techniques were significantly correlated and Passing-Bablok regressions showed no deviation from linearity between salFC and filtFC or quadFC. Using the routine assumption that the patients were correctly diagnosed using a post-tetracosactide TC threshold of 550 nmol/L the FC methods generating the best ROC curves were salFC and filtFC or cubFC 30 min after tetracosactide injection. CONCLUSIONS FC concentrations obtained by different techniques are significantly but not similarly correlated with TC. As, salFC and filtFC are more convenient to perform than methods involving CBG assays and are better correlated to TC during tetracosactide tests they may be preferred as FC surrogate assays.
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Perogamvros I, Ray DW, Trainer PJ. Regulation of cortisol bioavailability--effects on hormone measurement and action. Nat Rev Endocrinol 2012; 8:717-27. [PMID: 22890008 DOI: 10.1038/nrendo.2012.134] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Routine assessment of the hypothalamic-pituitary-adrenal axis relies on the measurement of total serum cortisol levels. However, most cortisol in serum is bound to corticosteroid-binding globulin (CBG) and albumin, and changes in the structure or circulating levels of binding proteins markedly affect measured total serum cortisol levels. Furthermore, high-affinity binding to CBG is predicted to affect the availability of cortisol for the glucocorticoid receptor. CBG is a substrate for activated neutrophil elastase, which cleaves the binding protein and results in the release of cortisol at sites of inflammation, enhancing its tissue-specific anti-inflammatory effects. Further tissue-specific modulation of cortisol availability is conferred by corticosteroid 11β-dehydrogenase. Direct assessment of tissue levels of bioavailable cortisol is not clinically practicable and measurement of total serum cortisol levels is of limited value in clinical conditions that alter prereceptor glucocorticoid bioavailability. Bioavailable cortisol can, however, be measured indirectly at systemic, extracellular tissue and cell levels, using novel techniques that have provided new insight into the transport, metabolism and biological action of glucocorticoids. A more physiologically informative approach is, therefore, now possible in the assessment of the hypothalamic-pituitary-adrenal axis, which could prove useful in clinical practice.
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Affiliation(s)
- Ilias Perogamvros
- Endocrine Sciences Research Group, School of Medicine, University of Manchester, A. V. Hill Building, Oxford Road, Manchester M13 9PT, UK.
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Serial changes in plasma total cortisol, plasma free cortisol, and tissue cortisol activity in patients with septic shock: an observational study. Shock 2012; 37:28-33. [PMID: 21993448 DOI: 10.1097/shk.0b013e318239b809] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Published data on adrenocortical function in septic shock have enrolled patients at various stages of critical illness and predominantly used plasma total cortisol, with minimal information on serial changes. Moreover, plasma free cortisol and tissue corticosteroid activity may not be strongly associated; however, few published data exist. The aim of this prospective observational study was to investigate serial changes in plasma total and free cortisol and tissue cortisol activity in septic shock. Twenty-nine adult patients admitted with septic shock to a tertiary-level intensive care unit were enrolled. A low-dose corticotropin test was performed on day 1. Plasma total and free cortisol, cortisone, transcortin, and urinary free cortisol and cortisone were analyzed on days 1 to 5, 7, and 10. Urinary and plasma cortisol-cortisone ratios (F:E ratio) were calculated as indices of 11-β hydroxysteroid dehydrogenase 2 and global 11-β hydroxysteroid dehydrogenase activity, respectively. Baseline total and free plasma cortisol values from 10 healthy control subjects were obtained for comparative analysis. Baseline plasma total and free cortisol levels were significantly higher than controls (457.8 ± 193 vs. 252 ± 66 nmol/L, P = 0.0002; and 50.83 ± 43.19 vs. 6.4 ± 3.2, P < 0.0001, respectively). Plasma free cortisol rose proportionately higher than total cortisol (124% ± 217.3% vs. 40% ± 33.2%, P = 0.007) following corticotropin. Baseline plasma and urinary F:E ratios were elevated over the reference ranges (13.13 ± 1.5, 1.69 ± 2.8) and were not correlated with plasma free cortisol values (r = 0.2, 0.3 respectively). Over the study period, total cortisol levels and plasma F:E ratios remained elevated, whereas plasma free cortisol levels and urinary F:E ratio declined. At baseline, plasma free cortisol levels were higher in patients who subsequently survived (23.7 ± 10.5 vs. 57.9 ± 45.8 nmol/L, P = 0.04). In septic shock, there is a differential response of plasma total and free cortisol over time and in response to corticotropin. Changes in plasma and urinary F:E ratios suggest tissue modulation of 11-β hydroxysteroid dehydrogenase activity. Total plasma cortisol measurements may not reflect the global adrenal response in septic shock.
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Perogamvros I, Kayahara M, Trainer PJ, Ray DW. Serum regulates cortisol bioactivity by corticosteroid-binding globulin-dependent and independent mechanisms, as revealed by combined bioassay and physicochemical assay approaches. Clin Endocrinol (Oxf) 2011; 75:31-8. [PMID: 21521274 DOI: 10.1111/j.1365-2265.2011.04003.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
CONTEXT Corticosteroid-binding globulin (CBG) is the principal carrier of natural glucocorticoids in the circulation, and we hypothesized that it modulates glucocorticoid bioactivity (GBA). Alterations in CBG, the presence of noncortisol, naturally occurring glucocorticoids and the use of potent, synthetic glucocorticoids, all make it difficult to assess adrenal activity in-vivo; these problems can be addressed by a glucocorticoid bioassay. DESIGN AND SUBJECTS A bioassay was developed for serum GBA and a physicochemical ultrafiltration-liquid chromatography-tandem mass spectrometry assay for free serum cortisol (FreeF). We studied individuals homozygous and heterozygous for a nonfunctioning CBG variant (CBG G237V) and healthy controls. RESULTS FreeF concentrations were similar in healthy controls, and those with absent functional CBG, but surprisingly we found low GBA in CBG null individuals. This may suggest that CBG delivers cortisol to target cells. However, further experiments revealed that dilution of serum in the bioassay caused release of cortisol from CBG, resulting in elevated GBA measurements in all but the CBG G237V homozygotes. Furthermore, we identified a specific and potent inhibitory effect of high concentration serum on glucocorticoid sensitivity of the recipient cells used in the bioassay. Analysis of inflammatory synovial fluid, a filtrate of serum with lower CBG concentration, revealed elevated free cortisol compared to noninflammatory synovial fluid, a change not attributable to interconversion between cortisol and cortisone. CONCLUSIONS Our findings reveal that dilution of CBG enhances cortisol release, and so bioactivity, and also that serum potently induces glucocorticoid resistance in target cells.
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Affiliation(s)
- I Perogamvros
- Department of Endocrinology, Christie HospitalEndocrine Sciences Research Group, University of Manchester, Manchester, UK
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Kirchhoff F, Briegel J, Vogeser M. Quantification of free serum cortisol based on equilibrium dialysis and isotope dilution-liquid chromatography–tandem mass spectrometry. Clin Biochem 2011; 44:894-9. [DOI: 10.1016/j.clinbiochem.2011.04.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 02/18/2011] [Accepted: 04/05/2011] [Indexed: 11/16/2022]
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Pretorius CJ, Galligan JP, McWhinney BC, Briscoe SE, Ungerer JP. Free cortisol method comparison: Ultrafiltation, equilibrium dialysis, tracer dilution, tandem mass spectrometry and calculated free cortisol. Clin Chim Acta 2011; 412:1043-7. [DOI: 10.1016/j.cca.2011.02.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Revised: 02/11/2011] [Accepted: 02/11/2011] [Indexed: 11/28/2022]
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Kerlik J, Penesova A, Vlcek M, Imrich R, Vogeser M, Radikova Z. Comparison of salivary cortisol and calculated free plasma cortisol during low-dose ACTH test in healthy subjects. Clin Biochem 2010; 43:764-7. [DOI: 10.1016/j.clinbiochem.2010.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 03/03/2010] [Accepted: 03/09/2010] [Indexed: 01/29/2023]
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Gatti R, Antonelli G, Prearo M, Spinella P, Cappellin E, De Palo EF. Cortisol assays and diagnostic laboratory procedures in human biological fluids. Clin Biochem 2009; 42:1205-17. [PMID: 19414006 DOI: 10.1016/j.clinbiochem.2009.04.011] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Revised: 04/23/2009] [Accepted: 04/27/2009] [Indexed: 01/25/2023]
Abstract
The overview of cortisol physiology, action and pathology is achieved in relation to the hypothalamic-pituitary-adrenal axis alteration by laboratory investigation. The measurements of cortisol and related compound levels in blood, urine and saliva used to study the physiological and pathological cortisol involvement, are critically reviewed. The immunoassay and chromatographic methods for cortisol measurement in the various biological fluids are examined in relation to their analytical performances, reference ranges and diagnostic specificity and sensitivity. Moreover, blood, urine and saliva cortisol level measurements are described taking into account the diagnostic implications. The deduction is that each method requires the definition of its own reference range and its related diagnostic cut-off levels. Thus, this review, stressing the analysis procedures, could help to understand and compare the results of the different assays.
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Affiliation(s)
- Rosalba Gatti
- Department of Medical Diagnostic and Spec. Ther., University of Padova (I), Italy
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15
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Corticosteroid Biology in Critical Illness: Modulatory Mechanisms and Clinical Implications. Intensive Care Med 2009. [DOI: 10.1007/978-0-387-92278-2_68] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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