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OBJECTIVE AND CONTEXT: Maturity onset diabetes of the young due to variants in HNF1A (HNF1A-MODY) is the most common form of monogenic diabetes. Individuals with HNF1A-MODY usually have a lean phenotype which contrasts with type 2 diabetes (T2DM). Data from hepatocytes derived from Hnf1a knock-out mice demonstrated dysregulation of 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1), which regulates glucocorticoid availability and action in target tissues, together with 11ß-HSD2 and steroid A-ring reductases, 5α- and 5ß-reductase. We proposed that altered glucocorticoid metabolism might underpin some of the phenotypic differences between patients with HNF1A-MODY and those with T2DM. DESIGN: A retrospective matched cohort study. PATIENTS AND MEASUREMENTS: 24-hours urine steroid metabolome profiling was carried out by gas chromatography-mass spectrometry in 35 subjects with HNF1A-MODY, 35 individuals with T2DM and 35 healthy controls matched for age, sex and BMI. The steroid metabolites were expressed as µg/L in all groups and measured in mid-morning urine in diabetic subjects and 24-hour urine collection in healthy controls. Hence, only ratios were compared not the individual steroids. Established ratios of glucocorticoid metabolites were used to estimate 11ß-HSD1/2 and 5α- and 5ß-reductase activities. RESULTS: While 11ß-HSD1 activity was similar in all groups, 11ß-HSD2 activity was significantly lower in subjects with HNF1A-MODY and T2DM than in healthy controls. The ratio of 5ß- to 5α-metabolites of cortisol was higher in subjects with HNF1A-MODY than in T2DM and healthy controls, probably due to increased activity of the 5ß-reductase (AKR1D1) in HNF1A-MODY. CONCLUSIONS: This is the first report of steroid metabolites in HNF1A-MODY. We have identified distinct differences in steroid metabolism pathways in subjects with HNF1A-MODY that have the potential to alter steroid hormone availability. Further studies are required to explore whether these changes link to phenotype.
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Diabetes Mellitus Tipo 2 , Animais , Estudos de Coortes , Fator 1-alfa Nuclear de Hepatócito/genética , Humanos , Hidrocortisona , Camundongos , Estudos RetrospectivosRESUMO
BACKGROUND: The development of accurate, non-invasive markers to diagnose and stage non-alcoholic fatty liver disease (NAFLD) is critical to reduce the need for an invasive liver biopsy and to identify patients who are at the highest risk of hepatic and cardio-metabolic complications. Disruption of steroid hormone metabolic pathways has been described in patients with NAFLD. AIM(S): To assess the hypothesis that assessment of the urinary steroid metabolome may provide a novel, non-invasive biomarker strategy to stage NAFLD. METHODS: We analysed the urinary steroid metabolome in 275 subjects (121 with biopsy-proven NAFLD, 48 with alcohol-related cirrhosis and 106 controls), using gas chromatography-mass spectrometry (GC-MS) coupled with machine learning-based Generalised Matrix Learning Vector Quantisation (GMLVQ) analysis. RESULTS: Generalised Matrix Learning Vector Quantisation analysis achieved excellent separation of early (F0-F2) from advanced (F3-F4) fibrosis (AUC receiver operating characteristics [ROC]: 0.92 [0.91-0.94]). Furthermore, there was near perfect separation of controls from patients with advanced fibrotic NAFLD (AUC ROC = 0.99 [0.98-0.99]) and from those with NAFLD cirrhosis (AUC ROC = 1.0 [1.0-1.0]). This approach was also able to distinguish patients with NAFLD cirrhosis from those with alcohol-related cirrhosis (AUC ROC = 0.83 [0.81-0.85]). CONCLUSIONS: Unbiased GMLVQ analysis of the urinary steroid metabolome offers excellent potential as a non-invasive biomarker approach to stage NAFLD fibrosis as well as to screen for NAFLD. A highly sensitive and specific urinary biomarker is likely to have clinical utility both in secondary care and in the broader general population within primary care and could significantly decrease the need for liver biopsy.
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Metaboloma , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/urina , Esteroides/metabolismo , Esteroides/urina , Adulto , Idoso , Biomarcadores/metabolismo , Biomarcadores/urina , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/metabolismo , Cirrose Hepática/urina , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Reprodutibilidade dos Testes , UrináliseRESUMO
Steroid 5ß-reductase (AKR1D1) is highly expressed in human liver where it inactivates endogenous glucocorticoids and catalyses an important step in bile acid synthesis. Endogenous and synthetic glucocorticoids are potent regulators of metabolic phenotype and play a crucial role in hepatic glucose metabolism. However, the potential of synthetic glucocorticoids to be metabolised by AKR1D1 as well as to regulate its expression and activity has not been investigated. The impact of glucocorticoids on AKR1D1 activity was assessed in human liver HepG2 and Huh7 cells; AKR1D1 expression was assessed by qPCR and Western blotting. Genetic manipulation of AKR1D1 expression was conducted in HepG2 and Huh7 cells and metabolic assessments were made using qPCR. Urinary steroid metabolite profiling in healthy volunteers was performed pre- and post-dexamethasone treatment, using gas chromatography-mass spectrometry. AKR1D1 metabolised endogenous cortisol, but cleared prednisolone and dexamethasone less efficiently. In vitro and in vivo, dexamethasone decreased AKR1D1 expression and activity, further limiting glucocorticoid clearance and augmenting action. Dexamethasone enhanced gluconeogenic and glycogen synthesis gene expression in liver cell models and these changes were mirrored by genetic knockdown of AKR1D1 expression. The effects of AKR1D1 knockdown were mediated through multiple nuclear hormone receptors, including the glucocorticoid, pregnane X and farnesoid X receptors. Glucocorticoids down-regulate AKR1D1 expression and activity and thereby reduce glucocorticoid clearance. In addition, AKR1D1 down-regulation alters the activation of multiple nuclear hormone receptors to drive changes in gluconeogenic and glycogen synthesis gene expression profiles, which may exacerbate the adverse impact of exogenous glucocorticoids.
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Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Gluconeogênese/efeitos dos fármacos , Fígado/enzimologia , Oxirredutases/efeitos dos fármacos , Adulto , Células Cultivadas , Voluntários Saudáveis , Hepatócitos , Humanos , MasculinoRESUMO
OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome. Steroid hormones and bile acids are potent regulators of hepatic carbohydrate and lipid metabolism. Steroid 5ß-reductase (AKR1D1) is highly expressed in human liver where it inactivates steroid hormones and catalyzes a fundamental step in bile acid synthesis. METHODS: Human liver biopsies were obtained from 34 obese patients and AKR1D1 mRNA expression levels were measured using qPCR. Genetic manipulation of AKR1D1 was performed in human HepG2 and Huh7 liver cell lines. Metabolic assessments were made using transcriptome analysis, western blotting, mass spectrometry, clinical biochemistry, and enzyme immunoassays. RESULTS: In human liver biopsies, AKR1D1 expression decreased with advancing steatosis, fibrosis and inflammation. Expression was decreased in patients with type 2 diabetes. In human liver cell lines, AKR1D1 knockdown decreased primary bile acid biosynthesis and steroid hormone clearance. RNA-sequencing identified disruption of key metabolic pathways, including insulin action and fatty acid metabolism. AKR1D1 knockdown increased hepatocyte triglyceride accumulation, insulin sensitivity, and glycogen synthesis, through increased de novo lipogenesis and decreased ß-oxidation, fueling hepatocyte inflammation. Pharmacological manipulation of bile acid receptor activation prevented the induction of lipogenic and carbohydrate genes, suggesting that the observed metabolic phenotype is driven through bile acid rather than steroid hormone availability. CONCLUSIONS: Genetic manipulation of AKR1D1 regulates the metabolic phenotype of human hepatoma cell lines, driving steatosis and inflammation. Taken together, the observation that AKR1D1 mRNA is down-regulated with advancing NAFLD suggests that it may have a crucial role in the pathogenesis and progression of the disease.
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Hepatócitos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Oxirredutases/fisiologia , Fenótipo , Ácidos e Sais Biliares/metabolismo , Células Hep G2 , Humanos , Inflamação/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade , Oxirredutases/genética , RNA Mensageiro/metabolismoRESUMO
Steroid hormones, including glucocorticoids and androgens, have potent actions to regulate many cellular processes within the liver. The steroid A-ring reductase, 5ß-reductase (AKR1D1), is predominantly expressed in the liver, where it inactivates steroid hormones and, in addition, plays a crucial role in bile acid synthesis. However, the precise functional role of AKR1D1 to regulate steroid hormone action in vitro has not been demonstrated. We have therefore hypothesised that genetic manipulation of AKR1D1 has the potential to regulate glucocorticoid availability and action in human hepatocytes. In both liver (HepG2) and non-liver cell (HEK293) lines, AKR1D1 over-expression increased glucocorticoid clearance with a concomitant decrease in the activation of the glucocorticoid receptor and the down-stream expression of glucocorticoid target genes. Conversely, knockdown of AKR1D1 using siRNA decreased glucocorticoid clearance and reduced the generation of 5ß-reduced metabolites. In addition, the two 5α-reductase inhibitors finasteride and dutasteride failed to effectively inhibit AKR1D1 activity in either cell-free or hepatocellular systems. Through manipulation of AKR1D1 expression and activity, we have demonstrated its potent ability to regulate glucocorticoid availability and receptor activation within human hepatoma cells. These data suggest that AKR1D1 may have an important role in regulating endogenous (and potentially exogenous) glucocorticoid action that may be of particular relevance to physiological and pathophysiological processes affecting the liver.
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Carcinoma Hepatocelular/metabolismo , Glucocorticoides/metabolismo , Neoplasias Hepáticas/metabolismo , Oxirredutases/metabolismo , Receptores de Glucocorticoides/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Fígado/metabolismoRESUMO
OBJECTIVE AND CONTEXT: Increasing adiposity, ageing and tissue-specific regeneration of cortisol through the activity of 11ß-hydroxysteroid dehydrogenase type 1 have been associated with deterioration in glucose tolerance. We undertook a longitudinal, prospective clinical study to determine if alterations in local glucocorticoid metabolism track with changes in glucose tolerance. DESIGN, PATIENTS, AND MEASUREMENTS: Sixty-five overweight/obese individuals (mean age 50.3 ± 7.3 years) underwent oral glucose tolerance testing, body composition assessment, subcutaneous adipose tissue biopsy and urinary steroid metabolite analysis annually for up to 5 years. Participants were categorized into those in whom glucose tolerance deteriorated ("deteriorators") or improved ("improvers"). RESULTS: Deteriorating glucose tolerance was associated with increasing total and trunk fat mass and increased subcutaneous adipose tissue expression of lipogenic genes. Subcutaneous adipose tissue 11ß-HSD1 gene expression decreased in deteriorators, and at study completion, it was highest in the improvers. There was a significant negative correlation between change in area under the curve glucose and 11ß-HSD1 expression. Global 11ß-HSD1 activity did not change and was not different between deteriorators and improvers at baseline or follow-up. CONCLUSION: Longitudinal deterioration in metabolic phenotype is not associated with increased 11ß-HSD1 activity, but decreased subcutaneous adipose tissue gene expression. These changes may represent a compensatory mechanism to decrease local glucocorticoid exposure in the face of an adverse metabolic phenotype.
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11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adiposidade/fisiologia , Gordura Subcutânea/metabolismo , Adiposidade/genética , Corticosteroides/metabolismo , Corticosteroides/urina , Adulto , Feminino , Glucocorticoides/metabolismo , Glucocorticoides/urina , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
BACKGROUND: Adrenal aldosterone excess is the most common cause of secondary hypertension and is associated with increased cardiovascular morbidity. However, adverse metabolic risk in primary aldosteronism extends beyond hypertension, with increased rates of insulin resistance, type 2 diabetes, and osteoporosis, which cannot be easily explained by aldosterone excess. METHODS: We performed mass spectrometry-based analysis of a 24-hour urine steroid metabolome in 174 newly diagnosed patients with primary aldosteronism (103 unilateral adenomas, 71 bilateral adrenal hyperplasias) in comparison to 162 healthy controls, 56 patients with endocrine inactive adrenal adenoma, 104 patients with mild subclinical, and 47 with clinically overt adrenal cortisol excess. We also analyzed the expression of cortisol-producing CYP11B1 and aldosterone-producing CYP11B2 enzymes in adenoma tissue from 57 patients with aldosterone-producing adenoma, employing immunohistochemistry with digital image analysis. RESULTS: Primary aldosteronism patients had significantly increased cortisol and total glucocorticoid metabolite excretion (all P < 0.001), only exceeded by glucocorticoid output in patients with clinically overt adrenal Cushing syndrome. Several surrogate parameters of metabolic risk correlated significantly with glucocorticoid but not mineralocorticoid output. Intratumoral CYP11B1 expression was significantly associated with the corresponding in vivo glucocorticoid excretion. Unilateral adrenalectomy resolved both mineralocorticoid and glucocorticoid excess. Postoperative evidence of adrenal insufficiency was found in 13 (29%) of 45 consecutively tested patients. CONCLUSION: Our data indicate that glucocorticoid cosecretion is frequently found in primary aldosteronism and contributes to associated metabolic risk. Mineralocorticoid receptor antagonist therapy alone may not be sufficient to counteract adverse metabolic risk in medically treated patients with primary aldosteronism. FUNDING: Medical Research Council UK, Wellcome Trust, European Commission.
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Context: The classic androgen synthesis pathway proceeds via dehydroepiandrosterone, androstenedione, and testosterone to 5α-dihydrotestosterone. However, 5α-dihydrotestosterone synthesis can also be achieved by an alternative pathway originating from 17α-hydroxyprogesterone (17OHP), which accumulates in congenital adrenal hyperplasia (CAH). Similarly, recent work has highlighted androstenedione-derived 11-oxygenated 19-carbon steroids as active androgens, and in CAH, androstenedione is generated directly from 17OHP. The exact contribution of alternative pathway activity to androgen excess in CAH and its response to glucocorticoid (GC) therapy is unknown. Objective: We sought to quantify classic and alternative pathway-mediated androgen synthesis in CAH, their diurnal variation, and their response to conventional GC therapy and modified-release hydrocortisone. Methods: We used urinary steroid metabolome profiling by gas chromatography-mass spectrometry for 24-hour steroid excretion analysis, studying the impact of conventional GCs (hydrocortisone, prednisolone, and dexamethasone) in 55 adults with CAH and 60 controls. We studied diurnal variation in steroid excretion by comparing 8-hourly collections (23:00-7:00, 7:00-15:00, and 15:00-23:00) in 16 patients with CAH taking conventional GCs and during 6 months of treatment with modified-release hydrocortisone, Chronocort. Results: Patients with CAH taking conventional GCs showed low excretion of classic pathway androgen metabolites but excess excretion of the alternative pathway signature metabolites 3α,5α-17-hydroxypregnanolone and 11ß-hydroxyandrosterone. Chronocort reduced 17OHP and alternative pathway metabolite excretion to near-normal levels more consistently than other GC preparations. Conclusions: Alternative pathway-mediated androgen synthesis significantly contributes to androgen excess in CAH. Chronocort therapy appears superior to conventional GC therapy in controlling androgen synthesis via alternative pathways through attenuation of their major substrate, 17OHP.
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Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Androgênios/metabolismo , Ritmo Circadiano , Glucocorticoides/administração & dosagem , Hidrocortisona/administração & dosagem , 17-alfa-Hidroxipregnenolona/urina , Adolescente , Hiperplasia Suprarrenal Congênita/metabolismo , Hiperplasia Suprarrenal Congênita/urina , Adulto , Androsterona/análogos & derivados , Androsterona/urina , Cortodoxona/análogos & derivados , Cortodoxona/urina , Preparações de Ação Retardada , Dexametasona/uso terapêutico , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glucocorticoides/uso terapêutico , Humanos , Hidrocortisona/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Pregnanotriol/análogos & derivados , Pregnanotriol/urina , Adulto JovemRESUMO
Androgen and estrogen biosynthesis in mammals requires the 17,20-lyase activity of cytochrome P450 17A1 (steroid 17-hydroxylase/17,20-lyase). Maximal 17,20-lyase activity in vitro requires the presence of cytochrome b5 (b5), and rare cases of b5 deficiency in human beings causes isolated 17,20-lyase deficiency. To study the consequences of conditional b5 removal from testicular Leydig cells in an animal model, we generated Cyb5(flox/flox):Sf1-Cre (LeyKO) mice. The LeyKO male mice had normal body weights, testis and sex organ weights, and fertility compared with littermates. Basal serum and urine steroid profiles of LeyKO males were not significantly different than littermates. In contrast, marked 17-hydroxyprogesterone accumulation (100-fold basal) and reduced testosterone synthesis (27% of littermates) were observed after human chorionic gonadotropin stimulation in LeyKO animals. Testis homogenates from LeyKO mice showed reduced 17,20-lyase activity and a 3-fold increased 17-hydroxylase to 17,20-lyase activity ratio, which were restored to normal upon addition of recombinant b5. We conclude that Leydig cell b5 is required for maximal androgen synthesis and to prevent 17-hydroxyprogesterone accumulation in the mouse testis; however, the b5-independent 17,20-lyase activity of mouse steroid 17-hydroxylase/17,20-lyase is sufficient for normal male genital development and fertility. LeyKO male mice are a good model for the biochemistry but not the physiology of isolated 17,20-lyase deficiency in human beings.
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Citocromos b5/genética , Células Intersticiais do Testículo/enzimologia , Esteroide 17-alfa-Hidroxilase/metabolismo , 17-alfa-Hidroxiprogesterona/sangue , Animais , Citocromos b5/metabolismo , Feminino , Fertilidade , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , FenótipoRESUMO
CONTEXT: 5α-Reductase 1 and 2 (SRD5A1, SRD5A2) inactivate cortisol to 5α-dihydrocortisol in addition to their role in the generation of DHT. Dutasteride (dual SRD5A1 and SRD5A2 inhibitor) and finasteride (selective SRD5A2 inhibitor) are commonly prescribed, but their potential metabolic effects have only recently been identified. OBJECTIVE: Our objective was to provide a detailed assessment of the metabolic effects of SRD5A inhibition and in particular the impact on hepatic lipid metabolism. DESIGN: We conducted a randomized study in 12 healthy male volunteers with detailed metabolic phenotyping performed before and after a 3-week treatment with finasteride (5 mg od) or dutasteride (0.5 mg od). Hepatic magnetic resonance spectroscopy (MRS) and two-step hyperinsulinemic euglycemic clamps incorporating stable isotopes with concomitant adipose tissue microdialysis were used to evaluate carbohydrate and lipid flux. Analysis of the serum metabolome was performed using ultra-HPLC-mass spectrometry. SETTING: The study was performed in the Wellcome Trust Clinical Research Facility, Queen Elizabeth Hospital, Birmingham, United Kingdom. MAIN OUTCOME MEASURE: Incorporation of hepatic lipid was measured with MRS. RESULTS: Dutasteride, not finasteride, increased hepatic insulin resistance. Intrahepatic lipid increased on MRS after dutasteride treatment and was associated with increased rates of de novo lipogenesis. Adipose tissue lipid mobilization was decreased by dutasteride. Analysis of the serum metabolome demonstrated that in the fasted state, dutasteride had a significant effect on lipid metabolism. CONCLUSIONS: Dual-SRD5A inhibition with dutasteride is associated with increased intrahepatic lipid accumulation.
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Inibidores de 5-alfa Redutase/farmacologia , Dutasterida/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Proteínas de Membrana/antagonistas & inibidores , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Adulto , Metabolismo dos Carboidratos/efeitos dos fármacos , Finasterida/farmacologia , Técnica Clamp de Glucose , Humanos , Resistência à Insulina , Fígado/efeitos dos fármacos , Masculino , Metaboloma/efeitos dos fármacos , Esteroides/metabolismoRESUMO
CONTEXT: Patients with hypopituitarism have increased morbidity and mortality. There is ongoing debate about the optimum glucocorticoid (GC) replacement therapy. OBJECTIVE: To assess the effect of GC replacement in hypopituitarism on corticosteroid metabolism and its impact on body composition. DESIGN AND PATIENTS: We assessed the urinary corticosteroid metabolite profile (using gas chromatography/mass spectrometry) and body composition (clinical parameters and full body DXA) of 53 patients (19 female, median age 46 years) with hypopituitarism (33 ACTH-deficient/20 ACTH-replete) (study A). The corticosteroid metabolite profile of ten patients with ACTH deficiency was then assessed prospectively in a cross over study using three hydrocortisone (HC) dosing regimens (20/10âmg, 10/10âmg and 10/5âmg) (study B) each for 6 weeks. 11 beta-hydroxysteroid dehydrogenase 1 (11ß-HSD1) activity was assessed by urinary THF+5α-THF/THE. SETTING: Endocrine Centres within University Teaching Hospitals in the UK and Ireland. MAIN OUTCOME MEASURES: Urinary corticosteroid metabolite profile and body composition assessment. RESULTS: In study A, when patients were divided into three groups - patients not receiving HC and patients receiving HC≤20âmg/day or HC>20âmg/day - patients in the group receiving the highest daily dose of HC had significantly higher waist-to-hip ratio (WHR) than the ACTH replete group. They also had significantly elevated THF+5α-THF/THE (P=0.0002) and total cortisol metabolites (P=0.015). In study B, patients on the highest HC dose had significantly elevated total cortisol metabolites and all patients on HC had elevated THF+5α-THF/THE ratios when compared to controls. CONCLUSIONS: In ACTH-deficient patients daily HC doses of >20âmg/day have increased WHR, THF+5α-THF/THE ratios and total cortisol metabolites. GC metabolism and induction of 11ß-HSD1 may play a pivitol role in the development of the metabolically adverse hypopituitary phenotype.
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Hormônio Adrenocorticotrópico/deficiência , Composição Corporal/efeitos dos fármacos , Glucocorticoides/metabolismo , Hidrocortisona/metabolismo , Hipopituitarismo/tratamento farmacológico , Hipopituitarismo/metabolismo , Adulto , Idoso , Estudos Cross-Over , Estudos Transversais , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/urina , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/urina , Hipopituitarismo/urina , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Relação Cintura-Quadril , Adulto JovemRESUMO
Glucocorticoids and androgens have both been implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD); androgen deficiency in males, androgen excess in females, and glucocorticoid excess in both sexes are associated with NAFLD. Glucocorticoid and androgen action are regulated at a prereceptor level by the enzyme 5α-reductase type 2 (SRD5A2), which inactivates glucocorticoids to their dihydrometabolites and converts T to DHT. We have therefore explored the role of androgens and glucocorticoids and their metabolism by SRD5A2 upon lipid homeostasis in human hepatocytes. In both primary human hepatocytes and human hepatoma cell lines, glucocorticoids decreased de novo lipogenesis in a dose-dependent manner. Whereas androgen treatment (T and DHT) increased lipogenesis in cell lines and in primary cultures of human hepatocytes from female donors, it was without effect in primary hepatocyte cultures from men. SRD5A2 overexpression reduced the effects of cortisol to suppress lipogenesis and this effect was lost following transfection with an inactive mutant construct. Conversely, pharmacological inhibition using the 5α-reductase inhibitors finasteride and dutasteride augmented cortisol action. We have demonstrated that manipulation of SRD5A2 activity can regulate lipogenesis in human hepatocytes in vitro. This may have significant clinical implications for those patients prescribed 5α-reductase inhibitors, in particular augmenting the actions of glucocorticoids to modulate hepatic lipid flux.
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3-Oxo-5-alfa-Esteroide 4-Desidrogenase/fisiologia , Glucocorticoides/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Lipogênese/genética , Proteínas de Membrana/fisiologia , Inibidores de 5-alfa Redutase/farmacologia , Adulto , Idoso , Androgênios/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/genética , Células Cultivadas , Feminino , Finasterida/farmacologia , Glucocorticoides/metabolismo , Humanos , Insulina/farmacologia , Lipogênese/efeitos dos fármacos , Masculino , Proteínas de Membrana/antagonistas & inibidores , Pessoa de Meia-Idade , FenótipoRESUMO
CONTEXT: Cushing's syndrome is characterized by marked changes in body composition (sarcopenia, obesity, and osteoporosis) that have similarities with those seen in aging. 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) converts glucocorticoids to their active form (cortisone to cortisol in humans), resulting in local tissue amplification of effect. OBJECTIVE: To evaluate 11ß-HSD1 expression and activity with age, specifically in muscle. To determine putative causes for increased activity with age and its consequences upon phenotypic markers of adverse aging. DESIGN: Cross-sectional observational study. SETTING: National Institute for Health Research-Wellcome Trust Clinical Research Facility, Birmingham, United Kingdom. PATIENTS OR OTHER PARTICIPANTS: Healthy human volunteers age 20 to 81 years (n = 134; 77 women, 57 men). INTERVENTIONS: Day attendance at research facility for baseline observations, body composition analysis by dual-energy x-ray absorptiometry, jump-plate mechanography, grip strength analysis, baseline biochemical profiling, urine collection, and vastus lateralis muscle biopsy. MAIN OUTCOME MEASURE(S): Skeletal muscle gene expression, urine steroid profile, bivariate correlations between expression/activity and phenotypic/biochemical variables. RESULTS: Skeletal muscle 11ß-HSD1 expression was increased 2.72-fold in women over 60 years of age compared to those aged 20-40 years; no differences were observed in men. There was a significant positive correlation between skeletal muscle 11ß-HSD1 expression and age in women across the group (rho = 0.40; P = .009). No differences in expression of 11ß-HSD type 2, glucocorticoid receptor, or hexose-6-phosphate dehydrogenase between age groups were observed in either sex. Urinary steroid markers of 11ß-HSD1, 11ß-HSD type 2, or 5α-reductase were similar between age groups. Skeletal muscle 11ß-HSD1 expression was associated with reduced grip strength in both sexes and correlated positively with percentage of body fat, homeostasis model of assessment for insulin resistance, total cholesterol, LH, and FSH and negatively with bone mineral content and IGF-1 in women. CONCLUSIONS: Skeletal muscle 11ß-HSD1 is up-regulated with age in women and is associated with reduced grip strength, insulin resistance, and an adverse body composition profile. Selective inhibition of 11ß-HSD1 may offer a novel strategy to prevent and/or reverse age-related sarcopenia.
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11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Envelhecimento/genética , Músculo Esquelético/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Composição Corporal/genética , Estudos Transversais , Feminino , Regulação Enzimológica da Expressão Gênica , Força da Mão/fisiologia , Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Sarcopenia/genética , Sarcopenia/metabolismo , Caracteres Sexuais , Adulto JovemRESUMO
CONTEXT: PAPSS2 (PAPS synthase 2) provides the universal sulfate donor PAPS (3'-phospho-adenosine-5'-phosphosulfate) to all human sulfotransferases, including SULT2A1, responsible for sulfation of the crucial androgen precursor dehydroepiandrosterone (DHEA). Impaired DHEA sulfation is thought to increase the conversion of DHEA toward active androgens, a proposition supported by the previous report of a girl with inactivating PAPSS2 mutations who presented with low serum DHEA sulfate and androgen excess, clinically manifesting with premature pubarche and early-onset polycystic ovary syndrome. PATIENTS AND METHODS: We investigated a family harboring two novel PAPSS2 mutations, including two compound heterozygous brothers presenting with disproportionate short stature, low serum DHEA sulfate, but normal serum androgens. Patients and parents underwent a DHEA challenge test comprising frequent blood sampling and urine collection before and after 100 mg DHEA orally, with subsequent analysis of DHEA sulfation and androgen metabolism by mass spectrometry. The functional impact of the mutations was investigated in silico and in vitro. RESULTS: We identified a novel PAPSS2 frameshift mutation, c.1371del, p.W462Cfs*3, resulting in complete disruption, and a novel missense mutation, c.809G>A, p.G270D, causing partial disruption of DHEA sulfation. Both patients and their mother, who was heterozygous for p.W462Cfs*3, showed increased 5α-reductase activity at baseline and significantly increased production of active androgens after DHEA intake. The mother had a history of oligomenorrhea and chronic anovulation that required clomiphene for ovulation induction. CONCLUSIONS: We provide direct in vivo evidence for the significant functional impact of mutant PAPSS2 on DHEA sulfation and androgen activation. Heterozygosity for PAPSS2 mutations can be associated with a phenotype resembling polycystic ovary syndrome.
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Androgênios/metabolismo , Desidroepiandrosterona/metabolismo , Hiperandrogenismo/genética , Complexos Multienzimáticos/genética , Mutação , Sulfato Adenililtransferase/genética , Sulfatos/metabolismo , Adolescente , Adulto , Sulfato de Desidroepiandrosterona/metabolismo , Família , Feminino , Humanos , Hiperandrogenismo/metabolismo , Masculino , Pessoa de Meia-Idade , Complexos Multienzimáticos/metabolismo , Sulfato Adenililtransferase/metabolismo , Adulto JovemRESUMO
OBJECTIVE: To determine the relationship between inflammation and glucocorticoid metabolism in vivo, in a clinical study of patients with inflammatory arthritis treated with anti-TNFα therapy. METHODS: Urine samples were collected from patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) as part of a multicentre study assessing responses to infliximab and etanercept. Systemic measures of glucocorticoid metabolism were assessed by gas chromatography/mass spectrometry at weeks 0 (baseline), 4 and 12 after anti-TNFα therapy. Clinical data including DAS28 and C-reactive protein were also collected. RESULTS: Systemic measures of 11ß-HSD1 activity in patients with inflammatory arthritis decreased significantly following anti-TNFα therapy in patients with RA and PsA. Additionally, the activity of the glucocorticoid inactivating enzyme 5α-reductase appeared to increase significantly. CONCLUSIONS: This study demonstrates, for the first time, that the increased 11ß-HSD1 activity seen in patients with inflammatory arthritis is mediated through TNFα. Furthermore, the changes in related glucocorticoid metabolising enzymes suggest that there is a coordinated change in glucocorticoid metabolism which promotes higher tissue glucocorticoid levels.
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Artrite Psoriásica/metabolismo , Artrite Reumatoide/metabolismo , Hidrocortisona/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Psoriásica/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Etanercepte , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Imunoglobulina G/uso terapêutico , Infliximab , Masculino , Pessoa de Meia-Idade , Receptores do Fator de Necrose Tumoral/uso terapêuticoRESUMO
OBJECTIVE: Dysregulation of enzymes that control local tissue steroid metabolism has been implicated in the pathogenesis of obesity and insulin resistance; however, longitudinal changes in glucocorticoid metabolism have not been investigated. This study was performed to evaluate the role of glucocorticoid metabolism in the development of insulin resistance and obesity and to identify biomarkers for future development of metabolic disease. DESIGN: This was a prospective longitudinal observation study conducted over 5 years. METHODS: A 24-h collection was used to serially analyze urinary glucocorticoid and mineralocorticoid metabolites in 57 obese and overweight patients with no prior diagnosis of diabetes mellitus, recruited from the community. RESULTS: Baseline higher 5α-reductase (5αR) activity, but not 11ß-hydroxysteroid dehydrogenase type 1 activity, was predictive of increased fasting insulin at final visit (11.4 compared with 7.4âmU/l in subjects with lower 5αR activity, P<0.05), area under the curve insulin response to oral glucose tolerance test (176.7 compared with 89.1âmU/l.h, P<0.01), and homeostasis model assessment (HOMA2-IR; 1.3 compared with 0.8, P<0.01). Higher total glucocorticoid production was associated with abnormal glucose tolerance and increased BMI. During this study, systolic blood pressure increased (equivalent to â¼1âmmHg/year), as did plasma sodium levels; this evidence of increased mineralocorticoid activity was associated with increased aldosterone metabolites and decreased 11ß-hydroxysteroid dehydrogenase type 2 activity. CONCLUSIONS: Increased 5αR activity and glucocorticoid secretion rate over time are linked with the development of metabolic disease, and may represent targets for therapeutic intervention, which merits further study.
Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Glucocorticoides/metabolismo , Insulina/sangue , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/sangue , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/urina , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/urina , Adulto , Idoso , Pressão Sanguínea , Feminino , Glucocorticoides/sangue , Glucocorticoides/urina , Humanos , Insulina/metabolismo , Resistência à Insulina , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Mineralocorticoides/metabolismo , Fenótipo , Valor Preditivo dos Testes , Estudos ProspectivosRESUMO
CONTEXT: Low birth weight is associated with adverse metabolic outcome in adulthood. Exposure to glucocorticoid (GC) excess in utero is associated with decreased birth weight, but the prospective longitudinal relationship between GC metabolism and growth has not been examined. OBJECTIVE: We have hypothesized that changes in GC metabolism leading to increased availability may impair growth. DESIGN: This was a prospective, longitudinal study with clinical measurements and 24-hour urinary steroid metabolite analysis at 1, 4, 12, 26, and 52 weeks after delivery in mothers and their babies. SETTING: The study was conducted with observations and samples collected in the volunteers' own homes. PARTICIPANTS: Healthy mothers and newborn babies/infants participated in the study. INTERVENTIONS: There were no interventions. MAIN OUTCOME MEASURES: Urinary steroid metabolite excretion quantified by gas chromatography/mass spectroscopy across the first year of life in relation to change in weight was measured. RESULTS: The total production of the GC metabolites quantified increased across the first year of life. Markers of 11ß-hydroxysteroid dehydrogenase type 1 activity increased from the age of 3 months as did those of 5α-reductase activity. After correcting for confounding variables, low markers of 11ß-hydroxysteroid dehydrogenase type 2 activity was associated with reduced absolute weight and decreased weight gain over the first year of life. In the mothers, 5α-reductase activity was low at birth and progressively increased to normal over the first 6 months postpartum. CONCLUSIONS: Increased GC exposure as a consequence of reduced 11ß-hydroxysteroid dehydrogenase type 2 activity is likely to be a critical determinant of growth in early life. This not only highlights the central role of GCs and their metabolism, but also emphasizes the need for detailed longitudinal analyses.
Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Peso Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Aumento de Peso/fisiologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos ProspectivosRESUMO
CONTEXT: Polycystic ovary syndrome (PCOS) is a triad of anovulation, insulin resistance, and hyperandrogenism. Androgen excess may correlate with metabolic risk and PCOS consensus criteria define androgen excess on the basis of serum T. Here we studied the utility of the androgen precursor serum androstenedione (A) in conjunction with serum T for predicting metabolic dysfunction in PCOS. PATIENTS AND METHODS: Eighty-six PCOS patients fulfilling Rotterdam diagnostic consensus criteria and 43 age- and body mass index-matched controls underwent measurement of serum androgens by tandem mass spectrometry and an oral glucose tolerance test with homeostatic model assessment of insulin resistance and insulin sensitivity index calculation. We analyzed 24-hour urine androgen excretion by gas chromatography/mass spectrometry. RESULTS: PCOS patients had higher levels of serum androgens and urinary androgen metabolites than controls (all P < .001). Within the PCOS cohort, both serum A and T were positively correlated with the free androgen index (T × 100/SHBG) and total androgen metabolite excretion (all P < .001). All subjects with T above the normal reference range [high T (HT)] also had high A (HA/HT group, n = 56). However, the remaining 30 patients had normal T levels, either in the presence of HA (HA/NT; n = 20) or normal A (NA/NT; n = 10). The groups did not differ in age or BMI. The HA/HT and HA/NT groups had higher total androgen excretion than NA/NT (P < .01 and P < .05, respectively). Multiple linear regression showed a strong negative association between serum androstenedione and insulin sensitivity. The incidence of dysglycemia according to an oral glucose tolerance test increased with the severity of androgen phenotype (NA/NT, 0%; HA/NT, 14%; HA/HT, 25%, P = .03). CONCLUSION: Simultaneous measurement of serum T and A represents a useful tool for predicting metabolic risk in PCOS women. HA levels are a sensitive indicator of PCOS-related androgen excess.
Assuntos
Androstenodiona/sangue , Hiperandrogenismo/diagnóstico , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/metabolismo , Adulto , Androgênios/sangue , Androgênios/urina , Androstenodiona/urina , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Hiperandrogenismo/complicações , Hiperandrogenismo/metabolismo , Fenótipo , Síndrome do Ovário Policístico/complicações , Valor Preditivo dos Testes , Adulto JovemRESUMO
CONTEXT: Despite lifelong steroid hormone replacement, there is excess morbidity and mortality associated with autoimmune Addison's disease. In health, adrenocortical cells undergo continuous self-renewal from a population of subcapsular progenitor cells, under the influence of ACTH, suggesting a therapeutic possibility. OBJECTIVE: We aimed to determine whether tetracosactide (synthetic ACTH1-24) could revive adrenal steroidogenic function in autoimmune Addison's disease. DESIGN, SETTING, AND PATIENTS: Thirteen patients (aged 16-65 y) with established autoimmune Addison's disease for more than 1 year were recruited at the Newcastle University Clinical Research Facility. INTERVENTION: The intervention included a 20-week study of regular sc tetracosactide (ACTH1-24) therapy. MAIN OUTCOME MEASURES: Serum and urine corticosteroids were measured during medication withdrawal at baseline and every 5 weeks during the study. RESULTS: Serum cortisol levels remained less than 100 nmol/L in 11 of 13 participants throughout the study. However, two women achieved peak serum cortisol concentrations greater than 400 nmol/L after 10 and 29 weeks of tetracosactide therapy, respectively, allowing withdrawal of corticosteroid replacement. Concurrently, urine glucocorticoid and mineralocorticoid metabolite excretion increased from subnormal to above the median of healthy controls. One of these responders remains well with improving peak serum cortisol (672 nmol/L) 28 months after stopping all treatments. The other responder showed a gradual reduction in serum cortisol and aldosterone over time, and steroid therapy was recommenced after a 28-week period without glucocorticoid replacement. CONCLUSION: This is the first study to demonstrate that established autoimmune Addison's disease is amenable to a regenerative medicine therapy approach.
Assuntos
Doença de Addison/tratamento farmacológico , Doença de Addison/fisiopatologia , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/fisiologia , Cosintropina/uso terapêutico , Doença de Addison/metabolismo , Adolescente , Corticosteroides/sangue , Corticosteroides/urina , Adulto , Idoso , Feminino , Humanos , Bombas de Infusão , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Resultado do Tratamento , Adulto JovemRESUMO
Apparent mineralocorticoid excess syndrome (AME) is an autosomal recessive genetic disorder caused by a deficiency in the enzyme 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD). We report a 36-year-old male who was hypertensive from birth and was diagnosed with AME at 8 years of age. There was continuous documentation of his hypertension and hypokalemic alkalosis throughout childhood, during which spironolactone and supplemental potassium were administered. At 33 years of age, the patient received a renal transplant, and following this the AME appears to have been cured clinically with remission of his low renin hypertension and hypokalemic alkalosis despite termination of treatment with spironolactone and potassium supplements.