1
|
Chailurkit LO, Aekplakorn W, Paiyabhroma N, Ongphiphadhanakul B. Global 11 Beta-Hydroxysteroid Dehydrogenase Activity Assessed by the Circulating Cortisol to Cortisone Ratio is Associated with Features of Metabolic Syndrome. Metab Syndr Relat Disord 2020; 18:291-295. [PMID: 32357081 DOI: 10.1089/met.2020.0013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: 11 Beta-hydroxysteroid dehydrogenases (11HSDs) are enzymes involved in the interconversion of cortisol and cortisone. There are two isoenzymes of 11HSD, 11HSD1 and 11HSD2. A causative role of 11HSD, particularly 11HSD1, in metabolic syndrome is well established in experimental animals. However, its role in human metabolic syndrome is less clear. We examined the influence of global 11HSD activity on metabolic syndrome in the general population, using the circulating cortisol:cortisone ratio as an index of global 11HSD activity. Methods: A subsample of 269 sera randomly selected from the Thai National Health Examination Survey IV samples was analyzed for serum cortisol and cortisone levels by liquid chromatography-tandem mass spectrometry. Results: There was no association between serum cortisol and age. However, circulating cortisone was negatively correlated with age (r = -0.12, P < 0.001), and the serum cortisol:cortisone ratio was positively associated with age (r = 0.03, P < 0.001). No association was found between serum cortisol:cortisone ratio and body mass index (BMI) or serum lipids. Multivariate analyses showed that the serum cortisol:cortisone ratio was associated with high blood pressure (P < 0.05) independent of age, BMI, and sex. In subjects without hypertension, the serum cortisol to cortisone ratio was associated with mean systolic blood pressure after controlling for age, BMI, and sex. The cortisol:cortisone ratio was not significantly different between subjects with and without diabetes. After excluding the 16 subjects with diabetes, it was found that the serum cortisol:cortisone ratio was positively associated with fasting plasma glucose independent of age, BMI, and sex (P < 0.01). Conclusions: The global index of 11HSD activity, assessed by the circulating cortisol:cortisone ratio, was related to high blood pressure and fasting plasma glucose and may serve as a proxy to global 11HSD activity.
Collapse
Affiliation(s)
- La-Or Chailurkit
- Department of Medicine and Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Wichai Aekplakorn
- Department of Community Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Nitchawat Paiyabhroma
- Department of Medicine and Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | | |
Collapse
|
2
|
Dhayat NA, Frey AC, Frey BM, d'Uscio CH, Vogt B, Rousson V, Dick B, Flück CE. Estimation of reference curves for the urinary steroid metabolome in the first year of life in healthy children: Tracing the complexity of human postnatal steroidogenesis. J Steroid Biochem Mol Biol 2015; 154:226-36. [PMID: 26297192 DOI: 10.1016/j.jsbmb.2015.07.024] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 11/15/2022]
Abstract
CONTEXT Complex steroid disorders such as P450 oxidoreductase deficiency or apparent cortisone reductase deficiency may be recognized by steroid profiling using chromatographic mass spectrometric methods. These methods are highly specific and sensitive, and provide a complete spectrum of steroid metabolites in a single measurement of one sample which makes them superior to immunoassays. The steroid metabolome during the fetal-neonatal transition is characterized by (a) the metabolites of the fetal-placental unit at birth, (b) the fetal adrenal androgens until its involution 3-6 months postnatally, and (c) the steroid metabolites produced by the developing endocrine organs. All these developmental events change the steroid metabolome in an age- and sex-dependent manner during the first year of life. OBJECTIVE The aim of this study was to provide normative values for the urinary steroid metabolome of healthy newborns at short time intervals in the first year of life. METHODS We conducted a prospective, longitudinal study to measure 67 urinary steroid metabolites in 21 male and 22 female term healthy newborn infants at 13 time-points from week 1 to week 49 of life. Urine samples were collected from newborn infants before discharge from hospital and from healthy infants at home. Steroid metabolites were measured by gas chromatography-mass spectrometry (GC-MS) and steroid concentrations corrected for urinary creatinine excretion were calculated. RESULTS 61 steroids showed age and 15 steroids sex specificity. Highest urinary steroid concentrations were found in both sexes for progesterone derivatives, in particular 20α-DH-5α-DH-progesterone, and for highly polar 6α-hydroxylated glucocorticoids. The steroids peaked at week 3 and decreased by ∼80% at week 25 in both sexes. The decline of progestins, androgens and estrogens was more pronounced than of glucocorticoids whereas the excretion of corticosterone and its metabolites and of mineralocorticoids remained constant during the first year of life. CONCLUSION The urinary steroid profile changes dramatically during the first year of life and correlates with the physiologic developmental changes during the fetal-neonatal transition. Thus detailed normative data during this time period permit the use of steroid profiling as a powerful diagnostic tool.
Collapse
Affiliation(s)
- Nasser A Dhayat
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland.
| | - Andrea C Frey
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland.
| | - Brigitte M Frey
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland.
| | - Claudia H d'Uscio
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland. claudia.d'
| | - Bruno Vogt
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland.
| | - Valentin Rousson
- Division of Biostatistics, Institute of Social and Preventive Medicine (IUMSP), University Hospital of Lausanne, Biopôle 2, Route de la Corniche 10, 1010 Lausanne, Switzerland.
| | - Bernhard Dick
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland.
| | - Christa E Flück
- Department of Pediatrics (Pediatric Endocrinology and Diabetology, University Children's Hospital) and Department of Clinical Research, University of Bern, Freiburgstrasse 15, 3010, Switzerland.
| |
Collapse
|
3
|
Luo L, Deng J, Wang DX, He J, Deng W. Regulation of epithelial sodium channel expression by oestradiol and progestogen in alveolar epithelial cells. Respir Physiol Neurobiol 2015; 216:52-62. [PMID: 26051998 DOI: 10.1016/j.resp.2015.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 05/15/2015] [Accepted: 06/01/2015] [Indexed: 01/11/2023]
Abstract
Oestrogen (E) and progestogen (P) exert regulatory effects on the epithelial Na(+) channel (ENaC) in the kidneys and the colon. However, the effects of E and P on the ENaC and on alveolar fluid clearance (AFC) remain unclear, and the mechanisms of action of these hormones are unknown. In this study, we showed that E and/or P administration increased AFC by more than 25% and increased the expression of the α and γ subunits of ENaC by approximately 35% in rats subjected to oleic acid-induced acute lung injury (ALI). A similar effect was observed in the dexamethasone-treated group. Furthermore, E and/or P treatment inhibited 11β-hydroxysteroid dehydrogenase (HSD) type 2 (11β-HSD2) activity, increased corticosterone expression and decreased the serum adrenocorticotrophic hormone (ACTH) levels. These effects were similar to those observed following treatment with carbenoxolone (CBX), a nonspecific HSD inhibitor. Further investigation showed that CBX further significantly increased AFC and α-ENaC expression after treatment with a low dose of E and/or P. In vitro, E or P alone inhibited 11β-HSD2 activity in a dose-dependent manner and increased α-ENaC expression by at least 50%, and E combined with P increased α-ENaC expression by more than 80%. Thus, E and P may augment the expression of α-ENaC, enhance AFC, attenuate pulmonary oedema by inhibiting 11β-HSD2 activity, and increase the active glucocorticoid levels in vivo and in vitro.
Collapse
Affiliation(s)
- Ling Luo
- Department of Respiratory Medicine, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jia Deng
- First Department of Internal Medicine, Traditional Chinese Medical Hospital of Jiangbei District, Chongqing, China
| | - Dao-xin Wang
- Department of Respiratory Medicine, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Jing He
- Department of Respiratory Medicine, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wang Deng
- Department of Respiratory Medicine, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
4
|
Huesler C, Lauterburg M, Frey BM, Frey FJ. Evidence for glucocorticoid-mediated hypertension after uninephrectomy. Physiol Rep 2013; 1:e00101. [PMID: 24303173 PMCID: PMC3841037 DOI: 10.1002/phy2.101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/28/2013] [Accepted: 08/29/2013] [Indexed: 12/04/2022] Open
Abstract
Recently, evidence was presented that uninephrectomy induces salt-sensitive hypertension in rats. The increase in blood pressure was abrogated by a mineralocorticoid receptor antagonist but not by an aldosterone synthase inhibitor. Here, we hypothesize that mineralocorticoid receptor activation occurred by an 11beta-hydroxy-glucocorticosteroid, as a consequence of dysregulated 11beta-hydroxysteroid dehydrogenase enzymes. Therefore, 3-week-old Sprague-Dawley rats were either uninephrectomized or sham operated and given a normal (0.4%) or high (8%)-salt diet. At week 8, a telemetric device was implanted, and during week 13 blood pressure continuously measured and urine was collected. The animals were sacrificed thereafter and liver and kidney were harvested. Steroid metabolites were analyzed by GC-MS and mRNA assessed by PCR. Uninephrectomy caused a distinct salt-sensitive hypertension. The increase in blood pressure correlated significantly with a decline in the apparent activity of 11beta-hydroxysteroid dehydrogenase 2 and an increase of 11beta-hydroxysteroid dehydrogenase 1, when urinary corticosterone metabolites were considered. These results were mirrored by the corresponding metabolite ratios assessed in renal and liver tissue. Changes in enzyme activities were in part explained by changes in the mRNA content. In conclusion, mineralocorticoid receptor-dependent salt sensitivity after UNX in rats appears to be mediated by glucocorticoids.
Collapse
Affiliation(s)
- Carina Huesler
- Department of Nephrology, Hypertension and Clinical Pharmacology, University Hospital Berne Berne, Switzerland
| | | | | | | |
Collapse
|
5
|
Lienhard D, Lauterburg M, Escher G, Frey FJ, Frey BM. High salt intake down-regulates colonic mineralocorticoid receptors, epithelial sodium channels and 11β-hydroxysteroid dehydrogenase type 2. PLoS One 2012; 7:e37898. [PMID: 22693583 PMCID: PMC3365073 DOI: 10.1371/journal.pone.0037898] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 04/26/2012] [Indexed: 11/18/2022] Open
Abstract
Besides the kidneys, the gastrointestinal tract is the principal organ responsible for sodium homeostasis. For sodium transport across the cell membranes the epithelial sodium channel (ENaC) is of pivotal relevance. The ENaC is mainly regulated by mineralocorticoid receptor mediated actions. The MR activation by endogenous 11β-hydroxy-glucocorticoids is modulated by the 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). Here we present evidence for intestinal segment specific 11β-HSD2 expression and hypothesize that a high salt intake and/or uninephrectomy (UNX) affects colonic 11β-HSD2, MR and ENaC expression. The 11β-HSD2 activity was measured by means of 3H-corticosterone conversion into 3H-11-dehydrocorticosterone in Sprague Dawley rats on a normal and high salt diet. The activity increased steadily from the ileum to the distal colon by a factor of about 3, an observation in line with the relevance of the distal colon for sodium handling. High salt intake diminished mRNA and protein of 11β-HSD2 by about 50% (p<0.001) and reduced the expression of the MR (p<0.01). The functionally relevant ENaC-β and ENaC-γ expression, a measure of mineralocorticoid action, diminished by more than 50% by high salt intake (p<0.001). The observed changes were present in rats with and without UNX. Thus, colonic epithelial cells appear to contribute to the protective armamentarium of the mammalian body against salt overload, a mechanism not modulated by UNX.
Collapse
Affiliation(s)
- Daniel Lienhard
- Department of Nephrology and Hypertension, University Hospital of Berne, Berne, Switzerland
| | - Meret Lauterburg
- Department of Nephrology and Hypertension, University Hospital of Berne, Berne, Switzerland
| | - Geneviève Escher
- Department of Nephrology and Hypertension, University Hospital of Berne, Berne, Switzerland
| | - Felix J. Frey
- Department of Nephrology and Hypertension, University Hospital of Berne, Berne, Switzerland
| | - Brigitte M. Frey
- Department of Nephrology and Hypertension, University Hospital of Berne, Berne, Switzerland
- Department of Clinical Research, University Hospital of Berne, Berne, Switzerland
- * E-mail:
| |
Collapse
|
6
|
Homology modeling and structural analysis of 11β-hydroxysteroid dehydrogenase type 2. Eur J Med Chem 2011; 46:1325-30. [PMID: 21333409 DOI: 10.1016/j.ejmech.2011.01.054] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 01/20/2011] [Accepted: 01/26/2011] [Indexed: 11/22/2022]
Abstract
11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) was homology-modeled by a Boltzmann-weighted randomized modeling procedure, using the X-ray crystal structure of 11βHSD1 (PDB code: 3HFG) as a template. The model exhibited significant 3D similarities to 11βHSD1. The contact energy profiles of the 11βHSD2 model were in good agreement with that of the X-ray structure of 11βHSD1. The secondary structure of the 11βHSD2 model exhibited a central 6-stranded all-parallel β-sheet sandwich-like structure, flanked on both sides by 3-helices. Ramachandran plots revealed that only 1.9% of the amino acid residues were in the disfavored region for 11βHSD2. Furthermore, the ligand-binding site (LBS) volume was calculated to be 845 Å(3), which suggests that the LBS of 11βHSD2 is sufficiently large to contain cofactors and substrates (ligands), such as NAD(+) and cortisol. The electrostatic analysis revealed that the 11βHSD2 model had a positive potential at the LBS, which indicates that 11βHSD2 possibly attracts negatively charged ligands at the LBS. These results indicate that the model was successfully evaluated and analyzed. Consequently, it is proposed that the 11βHSD2 model in the present study will be suitable for further in silico structure-based de novo antitumor drug designing. To the best of our knowledge, this is the latest report of an accurate 11βHSD2 model to target 11βHSD2 for the development of anticancer drugs.
Collapse
|
7
|
Yeyati NL, Altuna ME, Damasco MC, Mac Laughlin MA. Role of 11beta-hydroxysteroid dehydrogenase 2 renal activity in potassium homeostasis in rats with chronic renal failure. Braz J Med Biol Res 2009; 43:52-6. [PMID: 20027486 DOI: 10.1590/s0100-879x2009007500028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Accepted: 11/26/2009] [Indexed: 11/22/2022] Open
Abstract
Aldosterone concentrations vary in advanced chronic renal failure (CRF). The isozyme 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2), which confers aldosterone specificity for mineralocorticoid receptors in distal tubules and collecting ducts, has been reported to be decreased or normal in patients with renal diseases. Our objective was to determine the role of aldosterone and 11beta-HSD2 renal microsome activity, normalized for glomerular filtration rate (GFR), in maintaining K+ homeostasis in 5/6 nephrectomized rats. Male Wistar rats weighing 180-220 g at the beginning of the study were used. Rats with experimental CRF obtained by 5/6 nephrectomy (N = 9) and sham rats (N = 10) were maintained for 4 months. Systolic blood pressure and plasma creatinine (Pcr) concentration were measured at the end of the experiment. Sodium and potassium excretion and GFR were evaluated before and after spironolactone administration (10 mg.kg-1.day-1 for 7 days) and 11beta-HSD2 activity on renal microsomes was determined. Systolic blood pressure (means +/- SEM; Sham = 105 +/- 8 and CRF = 149 +/- 10 mmHg) and Pcr (Sham = 0.42 +/- 0.03 and CRF = 2.53 +/- 0.26 mg/dL) were higher (P < 0.05) while GFR (Sham = 1.46 +/- 0.26 and CRF = 0.61 +/- 0.06 mL/min) was lower (P < 0.05) in CRF, and plasma aldosterone (Pald) was the same in the two groups. Urinary sodium and potassium excretion was similar in the two groups under basal conditions but, after spironolactone treatment, only potassium excretion was decreased in CRF rats (sham = 0.95 +/- 0.090 (before) vs 0.89 +/- 0.09 microEq/min (after) and CRF = 1.05 +/- 0.05 (before) vs 0.37 +/- 0.07 microEq/min (after); P < 0.05). 11beta-HSD2 activity on renal microsomes was lower in CRF rats (sham = 0.807 +/- 0.09 and CRF = 0.217 +/- 0.07 nmol.min-1.mg protein-1; P < 0.05), although when normalized for mL GFR it was similar in both groups. We conclude that K+ homeostasis is maintained during CRF development despite normal Pald levels. This adaptation may be mediated by renal 11beta-HSD2 activity, which, when normalized for GFR, became similar to that of control rats, suggesting that mineralocorticoid receptors maintain their aldosterone selectivity.
Collapse
Affiliation(s)
- N L Yeyati
- Departamento de Fisiología y Biofísica, Facultad de Medicina, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | | | | | | |
Collapse
|
8
|
Balazs Z, Schweizer RAS, Frey FJ, Rohner-Jeanrenaud F, Odermatt A. DHEA induces 11 -HSD2 by acting on CCAAT/enhancer-binding proteins. J Am Soc Nephrol 2007; 19:92-101. [PMID: 18032797 DOI: 10.1681/asn.2007030263] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
11beta-Hydroxysteroid dehydrogenase (11beta-HSD) type 1 and type 2 catalyze the interconversion of inactive and active glucocorticoids. Impaired regulation of these enzymes has been associated with obesity, diabetes, hypertension, and cardiovascular disease. Previous studies in animals and humans suggested that dehydroepiandrosterone (DHEA) has antiglucocorticoid effects, but the underlying mechanisms are unknown. In this study, DHEA treatment markedly increased mRNA expression and activity of 11beta-HSD2 in a rat cortical collecting duct cell line and in kidneys of C57BL/6J mice and Sprague-Dawley rats. DHEA-treated rats tended to have reduced urinary corticosterone to 11-dehydrocorticosterone ratios. It was found that CCAAT/enhancer-binding protein-alpha (C/EBP-alpha) and C/EBP-beta regulated HSD11B2 transcription and that DHEA likely modulated the transcription of 11beta-HSD2 in a phosphatidylinositol-3 kinase/Akt-dependent manner by increasing C/EBP-beta mRNA and protein expression. Moreover, it is shown that C/EBP-alpha and C/EBP-beta differentially regulate the expression of 11beta-HSD1 and 11beta-HSD2. In conclusion, DHEA induces a shift from 11beta-HSD1 to 11beta-HSD2 expression, increasing conversion from active to inactive glucocorticoids. This provides a possible explanation for the antiglucocorticoid effects of DHEA.
Collapse
Affiliation(s)
- Zoltan Balazs
- Institute of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, CH-4056 Basel, Switzerland
| | | | | | | | | |
Collapse
|
9
|
Affiliation(s)
- Fred G Silva
- The United States and Canadian Academy of Pathology and the Medical College of Georgia, Emory University, 3643 Walton Way Extension, Building 6, Augusta, GA 30909, USA.
| |
Collapse
|
10
|
Amstislavsky S, Welker P, Frühauf JH, Maslova L, Ivanova L, Jensen B, Markel AL, Bachmann S. Renal and endocrine changes in rats with inherited stress-induced arterial hypertension (ISIAH). Histochem Cell Biol 2005; 125:651-9. [PMID: 16341522 DOI: 10.1007/s00418-005-0118-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2005] [Indexed: 10/25/2022]
Abstract
Hypertensive inbred rats (ISIAH; inherited stress-induced arterial hypertension) present with baseline hypertension (>170 mmHg in adult rats), but attain substantially higher values upon mild emotional stress. We aimed to characterize key parameters related to hypertension in ISIAH. Kidneys, adrenals, and systemic endocrine parameters were studied in ISIAH of different ages and compared to normotensive Wistar albino Glaxo (WAG) rats. Native organs were obtained for Western and PCR analysis. Perfusion-fixed organs were prepared for histopathology and quantitative histochemistry. Plasma renin and adrenal hormones were measured. Renal morphology was unaltered in ISIAH. The hypothalamic-pituitary-adrenocortical (HPA) axis was constitutively upregulated with enlarged adrenal cortices and enhanced plasma corticosterone levels. Plasma renin activity was not different between groups, whereas aldosterone levels were in part reduced. Juxtaglomerular NO synthase type 1, cyclooxygenase type 2, and renin expression were significantly reduced, whereas tubular gene products related to sodium transport (bumetanide-sensitive Na, K, 2Cl cotransporter type 2; thiazide-sensitive Na, Cl cotransporter; epithelial Na channel-alpha; 11beta-hydroxysteroid dehydrogenase type 2) were increased. These data suggest enhanced volume conservation by the kidney. Our data define ISIAH as an attractive model for the renal components determining salt and water homeostasis in hypertension. The specific condition of a basally stimulated HPA axis is highlighted, including the option to study effects superimposed by emotional stress.
Collapse
Affiliation(s)
- Sergej Amstislavsky
- Institute of Cytology and Genetics, Lavrentyev Avenue 10, 630090, Novosibirsk, Russia
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Zallocchi M, Matković L, Damasco MC. Adrenal 11-beta hydroxysteroid dehydrogenase activity in response to stress. Can J Physiol Pharmacol 2005; 82:422-5. [PMID: 15381967 DOI: 10.1139/y04-035] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This work studied the effect of stresses produced by simulated gavage or gavage with 200 mmol/L HCl two hours before adrenal extraction, on the activities of the 11beta-hydroxysteroid dehydrogenase 1 and 11beta-hydroxysteroid dehydrogenase 2 isoforms present in the rat adrenal gland. These activities were determined on immediately prepared adrenal microsomes following incubations with 3H-corticosterone and NAD+ or NADP+. 11-dehydrocorticosterone was measured as an end-product by TLC, and controls were adrenal microsomes from rats kept under basal (unstressed) conditions. 11beta-hydroxysteroid dehydrogenase 1 activity, but not 11beta-hydroxysteroid dehydrogenase 2 activity, was increased under both stress-conditions. Homeostatically, the stimulation of 11beta-hydroxysteroid dehydrogenase 1 activity would increase the supply of glucocorticoids. These, in turn, would activate the enzyme phenylethanolamine N-methyl transferase, thereby improving the synthesis of epinephrine as part of the stress-response.
Collapse
Affiliation(s)
- Marisa Zallocchi
- Dpto. Química Biológica, Facultad de Ciencias Exactas y Naturales (UBA), Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina.
| | | | | |
Collapse
|
12
|
Zallocchi ML, Matkovic L, Calvo JC, Damasco MC. Adrenal gland involvement in the regulation of renal 11beta-hydroxysteroid dehydrogenase 2. J Cell Biochem 2004; 92:591-602. [PMID: 15156570 DOI: 10.1002/jcb.20078] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Renal 11beta-hydroxysteroid dehydrogenase 2 (HSD2) catalyzes the conversion of active glucocorticoids to inert 11beta-keto compounds, thereby preventing the illicit binding of these hormones to mineralocorticoid receptors (MRs) and, thus, conferring aldosterone specificity. Absence or inhibition of HSD2 activity, originates a hypertensive syndrome with sodium retention and increased potassium elimination. Recent studies from our laboratory reported an increment of HSD2 activity in intact-stressed rats. To evaluate the adrenal involvement in this increase, we analyzed HSD2 activity and protein abundance in Intact, Sham-operated, and adrenalectomized rats under stress situations (gavage with an overload of 200 mM HCl (10 ml) and simulated gavage) or with corticosterone replacement. HSD2 activity was assessed in renal microsomal preparations obtained from different groups of animals. HSD2 protein abundance was measured by Western-blot. Circulating corticosterone was determined by radioimmunoassay. Sham-operated animals showed an increase in HSD2 activity and abundance compared to Intact and adrenalectomized rats suggesting the involvement of stress-related adrenal factors in HSD2 regulation. In the case of acidotic adrenalectomized animals, there was an increase in renal HSD2 activity when, along with the HCl overload, the rats were injected with corticosterone. This increment occurred without an increase in enzyme abundance. These results suggest the importance of circulating levels of glucocorticoids to respond to a metabolic acidosis, through regulation of HSD2 stimulation. The group subjected to a simulated gavage showed an increase in enzyme activity and protein abundance, thus demonstrating the need for both adrenal and extra-factors in the modulation of renal HSD2. The adrenalectomized animals injected with different doses of corticosterone, produced a progressive increase in enzyme activity and abundance, being significant for the dose of 68 microg corticosterone/100 g body weight. The highest dose (308 microg/100 g body weight) did not show any variation in activity and abundance compared to the control group. This biphasic effect of glucocorticoids could be explained taking into account their permissive and suppressive actions, depending on their blood levels. Knowing that stress induces multifactorial responses, it should not be surprising to observe a differential regulation in renal HSD2, confirming that different stressors act through different factors of both, adrenal and extra-adrenal origin.
Collapse
Affiliation(s)
- Marisa Laura Zallocchi
- Department of Biological Chemistry, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and PRHOM-CONICET, Buenos Aires, Argentina.
| | | | | | | |
Collapse
|
13
|
Schweizer RAS, Zürcher M, Balazs Z, Dick B, Odermatt A. Rapid hepatic metabolism of 7-ketocholesterol by 11beta-hydroxysteroid dehydrogenase type 1: species-specific differences between the rat, human, and hamster enzyme. J Biol Chem 2004; 279:18415-24. [PMID: 14973125 DOI: 10.1074/jbc.m313615200] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The role of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) in the local activation of the glucocorticoid receptor by converting inactive 11-ketoglucocorticoids to active 11beta-hydroxyglucocorticoids is well established. Currently, 11beta-HSD1 is considered a promising target for treatment of obese and diabetic patients. Here, we demonstrate a role of 11beta-HSD1 in the metabolism of 7-ketocholesterol (7KC), the major dietary oxysterol. Comparison of recombinant 11beta-HSD1, transiently expressed in human embryonic kidney 293 cells, revealed the stereo-specific interconversion of 7KC and 7beta-hydroxycholesterol by rat and human 11beta-HSD1, whereas the hamster enzyme interconverted 7alpha-hydroxycholesterol, 7beta-hydroxycholesterol, and 7KC. In contrast to lysates, which efficiently catalyzed both oxidation and reduction, intact cells exclusively reduced 7KC. These findings were confirmed using rat and hamster liver homogenates, intact rat hepatocytes, and intact hamster liver tissue slices. Reduction of 7KC was abolished upon inhibition of 11beta-HSD1 by carbenoxolone (CBX) or 2'-hydroxyflavanone. In vivo, after gavage feeding rats, 7KC rapidly appeared in the liver and was converted to 7beta-hydroxycholesterol. CBX significantly decreased the ratio of 7beta-hydroxycholesterol to 7KC, supporting the evidence from cell culture experiments for 11beta-HSD1-dependent reduction of 7KC to 7beta-hydroxycholesterol. Upon inhibition of 11beta-HSD1 by CBX, 7KC tended to accumulate in the liver, and plasma 7KC concentration increased. Together, our results suggest that 11beta-HSD1 efficiently catalyzes the first step in the rapid hepatic metabolism of dietary 7KC, which may explain why dietary 7KC has little or no effect on the development of atherosclerosis.
Collapse
Affiliation(s)
- Roberto A S Schweizer
- Division of Nephrology and Hypertension, Department of Clinical Research, University of Berne, 3010 Berne, Switzerland
| | | | | | | | | |
Collapse
|