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1.
Clin Endocrinol (Oxf) ; 100(4): 317-327, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38229583

RESUMO

OBJECTIVE: Endocrine systems are disrupted in acute illness, and symptoms reported following coronavirus disease 2019 (COVID-19) are similar to those found with clinical hormone deficiencies. We hypothesised that people with severe acute COVID-19 and with post-COVID symptoms have glucocorticoid and sex hormone deficiencies. DESIGN/PATIENTS: Samples were obtained for analysis from two UK multicentre cohorts during hospitalisation with COVID-19 (International Severe Acute Respiratory Infection Consortium/World Health Organisation [WHO] Clinical Characterization Protocol for Severe Emerging Infections in the UK study), and at follow-up 5 months after hospitalisation (Post-hospitalisation COVID-19 study). MEASUREMENTS: Plasma steroids were quantified by liquid chromatography-mass spectrometry. Steroid concentrations were compared against disease severity (WHO ordinal scale) and validated symptom scores. Data are presented as geometric mean (SD). RESULTS: In the acute cohort (n = 239, 66.5% male), plasma cortisol concentration increased with disease severity (cortisol 753.3 [1.6] vs. 429.2 [1.7] nmol/L in fatal vs. least severe, p < .001). In males, testosterone concentrations decreased with severity (testosterone 1.2 [2.2] vs. 6.9 [1.9] nmol/L in fatal vs. least severe, p < .001). In the follow-up cohort (n = 198, 62.1% male, 68.9% ongoing symptoms, 165 [121-192] days postdischarge), plasma cortisol concentrations (275.6 [1.5] nmol/L) did not differ with in-hospital severity, perception of recovery, or patient-reported symptoms. Male testosterone concentrations (12.6 [1.5] nmol/L) were not related to in-hospital severity, perception of recovery or symptom scores. CONCLUSIONS: Circulating glucocorticoids in patients hospitalised with COVID-19 reflect acute illness, with a marked rise in cortisol and fall in male testosterone. These findings are not observed 5 months from discharge. The lack of association between hormone concentrations and common post-COVID symptoms suggests steroid insufficiency does not play a causal role in this condition.


Assuntos
COVID-19 , Humanos , Masculino , Feminino , Hidrocortisona , Doença Aguda , Assistência ao Convalescente , Alta do Paciente , Glucocorticoides/uso terapêutico , Esteroides/uso terapêutico , Gravidade do Paciente , Testosterona
2.
Metabolites ; 13(2)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36837884

RESUMO

A number of steroids, including glucocorticoids and sex hormones, have been associated with neurodegenerative and cardiovascular conditions common in aging populations. The application of liquid chromatography tandem mass spectrometry (LC-MS/MS) steroid analysis offers an opportunity to conduct simultaneous multiplex steroid analysis within a given sample. In this paper, we describe the application of an LC-MS/MS steroid analysis method for the assessment of reference ranges of steroids in human saliva samples (200 µL) collected from older adults (age 50 years and above) enrolled in a European cohort investigating the risk for Alzheimer's dementia. Saliva samples were prepared using supported liquid extraction (SLE) along with a calibration curve and analysed using a Waters I-Class UPLC (Ultra Performance Liquid Chromatography) and a Sciex QTrap 6500+ mass spectrometer. Mass spectrometry parameters of steroids were optimised for each steroid and a method for the chromatographic separation of 19 steroids was developed. Lower limits of quantitation (LLOQs), linearity and other method criteria were assessed. In total, data from 125 participants (500 samples) were analysed and assessed for reference ranges (64 male, 61 female). A total of 19 steroids were detected in saliva within the range of the method. There were clear diurnal patterns in most of the steroid hormones detected. Sex differences were observed for androstenedione (A4), testosterone (T), cortisone (E) and aldosterone (Aldo). In the first sample of the day, dehydroepiandrosterone (DHEA) was significantly higher in healthy volunteers compared to those with Alzheimer's disease biomarkers. This LC-MS/MS method is suitable for the analysis of 19 steroids in saliva in adults.

3.
J Clin Endocrinol Metab ; 107(8): e3330-e3342, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35511873

RESUMO

CONTEXT: Body fat distribution is a risk factor for obesity-associated comorbidities, and adipose tissue dysfunction plays a role in this association. In humans, there is a sex difference in body fat distribution, and steroid hormones are known to regulate several cellular processes within adipose tissue. OBJECTIVE: Our aim was to investigate if intra-adipose steroid concentration and expression or activity of steroidogenic enzymes were associated with features of adipose tissue dysfunction in individuals with severe obesity. METHODS: Samples from 40 bariatric candidates (31 women, 9 men) were included in the study. Visceral (VAT) and subcutaneous adipose tissue (SAT) were collected during surgery. Adipose tissue morphology was measured by a combination of histological staining and semi-automated quantification. Following extraction, intra-adipose and plasma steroid concentrations were determined by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Aromatase activity was estimated using product over substrate ratio, while AKR1C2 activity was measured directly by fluorogenic probe. Gene expression was measured by quantitative PCR. RESULTS: VAT aromatase activity was positively associated with VAT adipocyte hypertrophy (P valueadj < 0.01) and negatively with plasma high-density lipoprotein (HDL)-cholesterol (P valueadj < 0.01), while SAT aromatase activity predicted dyslipidemia in women even after adjustment for waist circumference, age, and hormonal contraceptive use. We additionally compared women with high and low visceral adiposity index (VAI) and found that VAT excess is characterized by adipose tissue dysfunction, increased androgen catabolism mirrored by increased AKR1C2 activity, and higher aromatase expression and activity indices. CONCLUSION: In women, increased androgen catabolism or aromatization is associated with visceral adiposity and adipose tissue dysfunction.


Assuntos
Tecido Adiposo , Androgênios , Aromatase , Obesidade Mórbida , Tecido Adiposo/metabolismo , Androgênios/metabolismo , Aromatase/metabolismo , Distribuição da Gordura Corporal , Índice de Massa Corporal , Feminino , Hormônios Esteroides Gonadais/metabolismo , Humanos , Gordura Intra-Abdominal/metabolismo , Masculino , Obesidade Mórbida/metabolismo , Espectrometria de Massas em Tandem
4.
Cell Rep ; 37(6): 109958, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34758301

RESUMO

Impaired hepatic glucose and lipid metabolism are hallmarks of type 2 diabetes. Increased sulfide production or sulfide donor compounds may beneficially regulate hepatic metabolism. Disposal of sulfide through the sulfide oxidation pathway (SOP) is critical for maintaining sulfide within a safe physiological range. We show that mice lacking the liver- enriched mitochondrial SOP enzyme thiosulfate sulfurtransferase (Tst-/- mice) exhibit high circulating sulfide, increased gluconeogenesis, hypertriglyceridemia, and fatty liver. Unexpectedly, hepatic sulfide levels are normal in Tst-/- mice because of exaggerated induction of sulfide disposal, with associated suppression of global protein persulfidation and nuclear respiratory factor 2 target protein levels. Hepatic proteomic and persulfidomic profiles converge on gluconeogenesis and lipid metabolism, revealing a selective deficit in medium-chain fatty acid oxidation in Tst-/- mice. We reveal a critical role of TST in hepatic metabolism that has implications for sulfide donor strategies in the context of metabolic disease.


Assuntos
Diabetes Mellitus/patologia , Dislipidemias/patologia , Gluconeogênese , Fígado/patologia , Sulfetos/metabolismo , Tiossulfato Sulfurtransferase/fisiologia , Animais , Diabetes Mellitus/etiologia , Diabetes Mellitus/metabolismo , Dislipidemias/etiologia , Dislipidemias/metabolismo , Glucose/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Proteoma/metabolismo
5.
BMJ Open ; 11(10): e055435, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686560

RESUMO

OBJECTIVES: The steroid hormone vitamin D has roles in immunomodulation and bone health. Insufficiency is associated with susceptibility to respiratory infections. We report 25-hydroxy vitamin D (25(OH)D) measurements in hospitalised people with COVID-19 and influenza A and in survivors of critical illness to test the hypotheses that vitamin D insufficiency scales with illness severity and persists in survivors. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: Plasma was obtained from 295 hospitalised people with COVID-19 (International Severe Acute Respiratory and emerging Infections Consortium (ISARIC)/WHO Clinical Characterization Protocol for Severe Emerging Infections UK study), 93 with influenza A (Mechanisms of Severe Acute Influenza Consortium (MOSAIC) study, during the 2009-2010 H1N1 pandemic) and 139 survivors of non-selected critical illness (prior to the COVID-19 pandemic). Total 25(OH)D was measured by liquid chromatography-tandem mass spectrometry. Free 25(OH)D was measured by ELISA in COVID-19 samples. OUTCOME MEASURES: Receipt of invasive mechanical ventilation (IMV) and in-hospital mortality. RESULTS: Vitamin D insufficiency (total 25(OH)D 25-50 nmol/L) and deficiency (<25 nmol/L) were prevalent in COVID-19 (29.3% and 44.4%, respectively), influenza A (47.3% and 37.6%) and critical illness survivors (30.2% and 56.8%). In COVID-19 and influenza A, total 25(OH)D measured early in illness was lower in patients who received IMV (19.6 vs 31.9 nmol/L (p<0.0001) and 22.9 vs 31.1 nmol/L (p=0.0009), respectively). In COVID-19, biologically active free 25(OH)D correlated with total 25(OH)D and was lower in patients who received IMV, but was not associated with selected circulating inflammatory mediators. CONCLUSIONS: Vitamin D deficiency/insufficiency was present in majority of hospitalised patients with COVID-19 or influenza A and correlated with severity and persisted in critical illness survivors at concentrations expected to disrupt bone metabolism. These findings support early supplementation trials to determine if insufficiency is causal in progression to severe disease, and investigation of longer-term bone health outcomes.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Deficiência de Vitamina D , Estado Terminal , Estudos Transversais , Humanos , Influenza Humana/complicações , Influenza Humana/epidemiologia , Pandemias , SARS-CoV-2 , Sobreviventes , Vitamina D , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia
6.
Mol Metab ; 48: 101225, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785425

RESUMO

OBJECTIVE: Carbonyl reductase 1 (Cbr1), a recently discovered contributor to tissue glucocorticoid metabolism converting corticosterone to 20ß-dihydrocorticosterone (20ß-DHB), is upregulated in adipose tissue of obese humans and mice and may contribute to cardiometabolic complications of obesity. This study tested the hypothesis that Cbr1-mediated glucocorticoid metabolism influences glucocorticoid and mineralocorticoid receptor activation in adipose tissue and impacts glucose homeostasis in lean and obese states. METHODS: The actions of 20ß-DHB on corticosteroid receptors in adipose tissue were investigated first using a combination of in silico, in vitro, and transcriptomic techniques and then in vivo administration in combination with receptor antagonists. Mice lacking one Cbr1 allele and mice overexpressing Cbr1 in their adipose tissue underwent metabolic phenotyping before and after induction of obesity with high-fat feeding. RESULTS: 20ß-DHB activated both the glucocorticoid and mineralocorticoid receptor in adipose tissue and systemic administration to wild-type mice induced glucose intolerance, an effect that was ameliorated by both glucocorticoid and mineralocorticoid receptor antagonism. Cbr1 haploinsufficient lean male mice had lower fasting glucose and improved glucose tolerance compared with littermate controls, a difference that was abolished by administration of 20ß-DHB and absent in female mice with higher baseline adipose 20ß-DHB concentrations than male mice. Conversely, overexpression of Cbr1 in adipose tissue resulted in worsened glucose tolerance and higher fasting glucose in lean male and female mice. However, neither Cbr1 haploinsfficiency nor adipose overexpression affected glucose dyshomeostasis induced by high-fat feeding. CONCLUSIONS: Carbonyl reductase 1 is a novel regulator of glucocorticoid and mineralocorticoid receptor activation in adipose tissue that influences glucose homeostasis in lean mice.


Assuntos
Tecido Adiposo/metabolismo , Oxirredutases do Álcool/metabolismo , Glucocorticoides/metabolismo , Intolerância à Glucose/metabolismo , Obesidade/metabolismo , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais/genética , Oxirredutases do Álcool/genética , Animais , Corticosterona/análogos & derivados , Corticosterona/sangue , Corticosterona/farmacologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Intolerância à Glucose/genética , Células HEK293 , Homeostase/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/genética , Receptores de Mineralocorticoides/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
J Chromatogr A ; 1640: 461933, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588275

RESUMO

Liquid Chromatography tandem mass spectrometry (LC-MS/MS) is the gold-standard approach for androgen analysis in biological fluids, superseding immunoassays in selectivity, particularly at low concentrations. While LC-MS/MS is established for analysis of testosterone and androstenedione, 5α-dihydrotestosterone (DHT) presents greater analytical challenges. DHT circulates at low nanomolar concentrations in men and lower in women, ionizing inefficiently and suffering from isobaric interference from other androgens. Even using current LC-MS/MS technology, large plasma volumes (>0.5 mL) are required for detection, undesirable clinically and unsuitable for animals. This study investigated derivatization approaches using hydrazine-based reagents to enhance ionization efficiency and sensitivity of analysis of DHT by LC-MS/MS. Derivatization of DHT using 2-hydrazino-1-methylpyridine (HMP) and 2-hydrazino-4-(trifluoromethyl)-pyrimidine (HTP) were compared. A method was validated using an UHPLC interfaced by electrospray with a triple quadruple mass spectrometer , analyzing human plasma (male and post-menopausal women) following solid-phase extraction. HMP derivatives were selected for validation affording greater sensitivity than those formed with HTP. HMP derivatives were detected by selected reaction monitoring (DHT-HMP m/z 396→108; testosterone-HMP m/z 394→108; androstenedione-HMP m/z 392→108). Chromatographic separation of androgen derivatives was optimized, carefully separating isobaric interferents and acceptable outputs for precision and trueness achieved following injection of 0.4 pg on column (approximately 34 pmol/L). HMP derivatives of all androgens tested could be detected in low plasma volumes: male (100 µL) and post-menopausal female (200 µL), and derivatives were stable over 30 days at -20°C. In conclusion, HMP derivatization, in conjunction with LC-MS/MS, is suitable for quantitative analysis of DHT, testosterone and androstenedione in low plasma volumes, offering advantages in sensitivity over current methodologies.


Assuntos
Di-Hidrotestosterona/sangue , Hidrazinas/química , Piridinas/química , Espectrometria de Massas em Tandem/métodos , Adulto , Androgênios/sangue , Androstenodiona/sangue , Bioensaio , Calibragem , Cromatografia Líquida , Feminino , Humanos , Hidrazinas/síntese química , Masculino , Piridinas/síntese química , Padrões de Referência , Reprodutibilidade dos Testes , Testosterona/sangue
8.
J Steroid Biochem Mol Biol ; 199: 105598, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31958632

RESUMO

Hypovitaminosis D and hypervitaminosis D are well recognised disorders in dogs. Hypovitaminosis D can occur following consumption of a diet inadequately supplemented with vitamin D or as a sequelae of severe intestinal disease. Hypervitaminosis D may occur as a result of consuming proprietary dog foods over-supplemented with vitamin D or through ingestion of vitamin D containing medicinal products or rodenticides. Consequently, there is a clear need to establish a methodology that can accurately quantify vitamin D metabolites across a broad dynamic range in dogs. The existence of C3-epimers of vitamin D metabolites has yet to be elucidated in dogs, yet are known to interfere with the analysis of vitamin D and have unknown biological activity in other species. Here, we describe the development and validation of a sensitive, specific and robust analytical liquid chromatography tandem mass spectrometry (LC-MS/MS) assay capable of separating and accurately measuring 25-hydroxyvitamin-D2/3 (25(OH)D2/3) and 3-epi-25-hydroxyvitamin-D2/3 (3-epi-25(OH)D2/3). We describe a simplified workflow utilising supported liquid extraction (SLE) without derivatization that provides good linearity (mean r > 0.996) and accuracy across a broad dynamic range of 4-500 nmol/L for D3 metabolites and 7.8-500 nmol/L for D2 metabolites. Upon application of this assay to 117 canine serum samples, 25(OH)D3 was detectable in all samples with a median concentration of 82.1 nmol/L (inter-quartile range (IQR) 59.7-101.8 nmol/L). 3-epi-25(OH)D3 could be detected in 87.2 % of the study population, with a median concentration of 5.2 nmol/L (2.4-8.1 nmol/L). However, 3-epi-25(OH)D3 was quantified below the LLOQ in 40.2 % of these samples. 3-epi-25(OH)D3 contributed on average 6.3 % to 25(OH)D3 status (contribution ranges from 0 to 23.8%) and a positive correlation was detected between 25(OH)D3 and 3-epi-25(OH)D3 concentrations. Free 25(OH)D was also measured using an immunoassay with a median concentration of 15.2 pmol/L (12.5-23.2 pmol/L), and this metabolite was also positively correlated to both 3-epi-25(OH)D3 and 25(OH)D3 concentrations. D2 metabolites were not detected in canine serum as expected. Vitamin D metabolite concentrations were variable between individuals, and research into the causes of this variation should include factors such as breed, age, sex and neuter status to determine the impact of genetic and hormonal factors. Given the clinical importance of vitamin D in dogs, and the immense potential for utilising this species as a model for human disease, further elucidation of the vitamin D pathway in this species would provide immense clinical and research benefit.


Assuntos
Cromatografia Líquida , Espectrometria de Massas em Tandem , Vitamina D/análogos & derivados , Vitamina D/sangue , Animais , Suplementos Nutricionais , Cães , Feminino , Humanos , Masculino , Vitamina D/isolamento & purificação , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/patologia
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