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1.
J Clin Endocrinol Metab ; 106(3): 814-825, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33236103

RESUMO

CONTEXT: Oral once-daily dual-release hydrocortisone (DR-HC) replacement therapy has demonstrated an improved metabolic profile compared to conventional 3-times-daily (TID-HC) therapy among patients with primary adrenal insufficiency. This effect might be related to a more physiological cortisol profile, but also to a modified pattern of cortisol metabolism. OBJECTIVE: This work aimed to study cortisol metabolism during DR-HC and TID-HC. DESIGN: A randomized, 12-week, crossover study was conducted. INTERVENTION AND PARTICIPANTS: DC-HC and same daily dose of TID-HC were administered to patients with primary adrenal insufficiency (n = 50) vs healthy individuals (n = 124) as controls. MAIN OUTCOME MEASURES: Urinary corticosteroid metabolites were measured by gas chromatography/mass spectrometry at 24-hour urinary collections. RESULTS: Total cortisol metabolites decreased during DR-HC compared to TID-HC (P < .001) and reached control values (P = .089). During DR-HC, 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) activity measured by tetrahydrocortisol + 5α-tetrahydrocortisol/tetrahydrocortisone ratio was reduced compared to TID-HC (P < .05), but remained increased vs controls (P < .001). 11ß-HSD2 activity measured by urinary free cortisone/free cortisol ratio was decreased with TID-HC vs controls (P < .01) but normalized with DR-HC (P = .358). 5α- and 5ß-reduced metabolites were decreased with DR-HC compared to TID-HC. Tetrahydrocortisol/5α-tetrahydrocortisol ratio was increased during both treatments, suggesting increased 5ß-reductase activity. CONCLUSIONS: The urinary cortisol metabolome shows striking abnormalities in patients receiving conventional TID-HC replacement therapy, with increased 11ß-HSD1 activity that may account for the unfavorable metabolic phenotype in primary adrenal insufficiency. Its change toward normalization with DR-HC may mediate beneficial metabolic effects. The urinary cortisol metabolome may serve as a tool to assess optimal cortisol replacement therapy.


Assuntos
Doença de Addison , Hidrocortisona/farmacocinética , Esteroides/urina , Doença de Addison/tratamento farmacológico , Doença de Addison/metabolismo , Doença de Addison/urina , Adulto , Idoso , Cortisona/metabolismo , Cortisona/urina , Estudos Cross-Over , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Europa (Continente) , Feminino , Humanos , Hidrocortisona/uso terapêutico , Hidrocortisona/urina , Masculino , Metaboloma/efeitos dos fármacos , Pessoa de Meia-Idade , Pregnanos/metabolismo , Pregnanos/urina , Esteroides/metabolismo , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/metabolismo , Tetra-Hidrocortisona/urina , Urinálise
2.
J Pharm Biomed Anal ; 107: 450-5, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25668797

RESUMO

Chronic stress as well as major depressive disorders is associated with cortisol metabolism. Two enzymes modulate cortisol (F) and cortisone (E) interconversion: 11ß-hydroxysteroid dehydrogenase type 1 and type 2 (11ß-HSD1 and 11ß-HSD2). Furthermore, F and E were inactivated by 5α and 5ß reductases to their tetrahydro-metabolites: tetrahydrocortisol (THF), allo-tetrahydrocortisol (5α-THF) and tetrahydrocortisone (THE). To better understand depression a LC-MS/MS method for simultaneous determination of F, E THF, 5α-THF and THE in human urine has been developed and validated. The quantification range was 0.1-160 ng mL(-1) for F and E, and 0.2-160 ng mL(-1) for the tetrahydro-metabolites, with >86.1% recovery for all analytes. The nocturnal urine concentrations of F, E and tetrahydro-metabolites in 12 apparently healthy male adult volunteers and 12 drug-free male patients (age range, 20-50 years) with a diagnosis of depression were analyzed. A series of significant changes in glucocorticoid metabolism can be detected: F/E ratios and (THF+5α-THF)/THE ratios as well as F and THF concentrations were significantly higher in depression patients than in healthy subjects (p<0.05); 5α-THF/F ratios, 5α-THF/THF ratios as well as 5α-THF concentrations were significantly lower in depression patients (p<0.05). The results pointed to the decreased 11ß-HSD2 activity and a dysfunction in the 5α-reductase pathway in depressed patients. This method allows the assessment of 11ß-HSD1/2 and 5α/ß-reductase activities in a single analytical run providing an innovative tool to explain the potential etiology of depression.


Assuntos
Cortisona/química , Cortisona/urina , Transtorno Depressivo Maior/urina , Hidrocortisona/química , Hidrocortisona/urina , Tetra-Hidrocortisona/química , Tetra-Hidrocortisona/urina , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Adulto , Estudos de Casos e Controles , Colestenona 5 alfa-Redutase/metabolismo , Cromatografia Líquida/métodos , Cortisona/metabolismo , Transtorno Depressivo Maior/metabolismo , Glucocorticoides/química , Glucocorticoides/metabolismo , Glucocorticoides/urina , Humanos , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem/métodos , Tetra-Hidrocortisol/análogos & derivados , Tetra-Hidrocortisol/química , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/metabolismo , Adulto Jovem
3.
J Psychiatr Res ; 52: 57-62, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24534618

RESUMO

Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis is suggested as a pathophysiological factor in bipolar disorder and schizophrenia. Increased clearance of cortisol was recently indicated as a component in the HPA axis hyperdrive. The aim of the present study was to test the model of increased cortisol metabolism in a new replication sample separately and combined with a previously published sample of bipolar disorder and schizophrenia. Spot urine was sampled from 212 healthy controls (HC) and 221 patients with a schizophrenia spectrum disorder (SCZ, n = 115) and bipolar disorder (BD, n = 106). Of these, a subsample of 169 HC and 155 patients was included in a previous report. Urinary free cortisol, cortisone and their metabolites were measured, and the activities of 5α-reductase, 5ß-reductase and 11ß-HSD were estimated and analyzed for differences between groups. In the new sample, there was increased enzyme activity in SCZ for 5ß-reductase (p = 0.024 vs HC; p = 0.027 vs BD) and 11ß-HSD2 (p = 0.014 vs HC; p = 0.004 vs BD). In the combined sample, there was increased activity in SCZ for 5α-reductase (p < 0.001 vs HC; p = 0.020 vs BD), 5ß-reductase (p < 0.001 vs HC; p = 0.045 vs BD) and 11ß-HSD2 (p < 0.001 vs HC; p = 0.043 vs BD), and in BD for 5ß-reductase (p = 0.002), 11ß-HSD2 (p = 0.039) and 5α-reductase (trend, p = 0.084) (all vs HC). The findings confirm increased systemic cortisol metabolism in BD and SCZ. This is most consistent in SCZ, with BD taking an intermediate position. The design makes it impossible to determine the direction of the effect. However, the findings merit further study of cortisol metabolism as a possible component in the HPA axis dysfunction and pathophysiology of BD and SCZ.


Assuntos
Transtorno Bipolar/metabolismo , Hidrocortisona/metabolismo , Esquizofrenia/metabolismo , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Tetra-Hidrocortisol/análogos & derivados , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisona/metabolismo , Adulto Jovem
4.
Clin Endocrinol (Oxf) ; 78(5): 700-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22233384

RESUMO

OBJECTIVE: Increased glucocorticoid metabolite excretion and enhanced expression and activity of 11ß-hydroxysteroid dehydrogenase type 1 in adipose tissue are closely correlated with obesity and its detrimental consequences. Weight loss ameliorates the latter. The aim of this study was to explore whether increased glucocorticoid exposure in obesity is improved with substantial weight loss and thus is a consequence rather than a cause of obesity. DESIGN AND PATIENTS: A prospective cohort study in 31 women. MEASUREMENTS: 11ß-HSD type 1 expression and activity, urinary glucocorticoid metabolite excretion, body composition including regional adipose tissue depots and insulin resistance by HOMA-IR before and 2 years after gastric bypass surgery. RESULTS: After weight loss, excretion of cortisol and cortisone metabolites decreased. Both cortisol and cortisone metabolite excretion correlated with central obesity, where the intraabdominal fat depot showed the strongest association. Cortisol metabolites correlated with 11ß-HSD type 1 activity in abdominal subcutaneous adipose tissue. The ratio of cortisol to cortisone metabolites [(5α-tetrahydrocortisol (5αTHF) + tetrahydrocortisol (THF) + α-cortol)/(tetrahydrocortisone (THE) + α-cortolone)] and the ratio of 5α-THF/THF both decreased after stable weight loss, reflecting a downregulation of the net activities of 11ß-HSD type 1 and 5α-reductase. CONCLUSION: Long-term weight loss in women is not only followed by reduced glucocorticoid production, but also favourably decreases the global and tissue-specific activity of the cortisol-activating enzyme 11 ß-HSD type 1, possibly contributing to the health benefits of bariatric surgery.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Hidrocortisona/urina , Obesidade/metabolismo , Obesidade/urina , Redução de Peso/fisiologia , Adulto , Estudos de Coortes , Cortisona/urina , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisona/metabolismo
5.
Chem Pharm Bull (Tokyo) ; 58(3): 344-53, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20190439

RESUMO

Here, we describe the chemical synthesis of the complete sets of 18 novel 3- and 21-monosulfates and their double-conjugated form of tetrahydrocortisol (THF), tetrahydro-11-deoxycortisol (THS), and tetrahydrocortisone (THE) in the 5alpha- and 5beta-series. The principal reactions involved are: (1) selective protection of a specific hydroxy group in substrates; (2) catalytic hydrogenation at C-5 of Delta(4)-3-ketosteroids with 10% Pd(OH)(2)/C to yield 3-oxo-5beta-steroids and reductive allomerization with 10% Pd/C to yield 3-oxo-5alpha-isomers; (3) reduction of the resulting 3-oxo-5beta- and 3-oxo-5alpha-steroids to the corresponding 3alpha-hydroxy-compounds with Zn(BH(4))(2) and K-Selectride((R)), respectively; and (4) sulfation of hydroxy groups at C-3 and/or C-21 in the tetrahydrocorticosteroid derivatives with sulfur trioxide-triethylamine complex.


Assuntos
Sulfatos/síntese química , Tetra-Hidrocortisol/síntese química , Conformação Molecular , Estereoisomerismo , Sulfatos/química , Sulfatos/metabolismo , Tetra-Hidrocortisol/química , Tetra-Hidrocortisol/metabolismo
6.
Eur J Appl Physiol ; 108(4): 681-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19902242

RESUMO

Intense physical exercise activates the hypothalamic-pituitary-adrenocortical axis but little is known about changes in glucocorticoid sensitivity at the target cell level. No data are available on the acute effects of exercise on 11beta-hydroxysteroid dehydrogenase (11beta-HSD) type 1 activity, which generates biologically active cortisol from inactive cortisone and is expressed also in skeletal muscle. Fifteen healthy, trained males (age mean +/- SE 28 +/- 1) were assessed on three non-consecutive days: at rest, during an endurance and strength sessions. During each session, between 1000 and 1600 hours, 6-h urine and four salivary samples were collected. Urinary total tetrahydrocortisol (THF) + alloTHF, tetrahydrocortisone (THE), cortisol (F) and cortisone (E) were measured with HPLC-tandem mass spectrometry; urinary-unconjugated F and E were measured by HPLC-UV. Salivary cortisol and interleukin (IL)-6 were measured by RIA and ELISA, respectively. Both endurance and strength exercises caused an increase in (THF + alloTHF)/THE ratio (mean +/- SE 1.90 +/- 0.07 and 1.82 +/- 0.05 vs. 1.63 +/- 0.06, P < 0.01 and P = 0.03, respectively), consistent with increased systemic 11beta-HSD type 1 activity. No relationship was found with age, BMI, VO(2max) maximal power load or perceived exertion. No significant change was apparent in F/E ratio, an index of 11beta-HSD type 2 activity. No effect of exercise on salivary cortisol and IL-6 was observed, whereas a significant effect of sampling time was found. Intense physical exercise acutely increases systemic 11beta-HSD type 1 activity in humans. Such an increase may lead to higher cortisol concentration in target tissues, notably in skeletal muscle where it could contribute to limit exercise-induced muscle inflammatory response.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Esforço Físico/fisiologia , Adulto , Cortisona/metabolismo , Cortisona/urina , Exercício Físico/fisiologia , Saúde , Humanos , Hidrocortisona/metabolismo , Hidrocortisona/urina , Interleucina-6/metabolismo , Masculino , Resistência Física/fisiologia , Treinamento Resistido , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/metabolismo , Tetra-Hidrocortisona/urina , Regulação para Cima
7.
Fertil Steril ; 91(3): 842-50, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18402944

RESUMO

OBJECTIVE: To investigate possible effects of insulin-sensitizing treatment on cortisol metabolism in insulin-resistant patients with polycystic ovary syndrome (PCOS). DESIGN: Randomized placebo-controlled study. SETTING: Academic tertiary care medical center. PATIENT(S): Thirty insulin-resistant PCOS patients. INTERVENTION(S): Sixteen weeks of pioglitazone (30 mg/day) or placebo treatment. MAIN OUTCOME MEASURE(S): Twenty-four-hour 20 min integrated blood sampling for measurement of cortisol and 24 h urinary excretion of steroid metabolites. Relative 5alpha-reductase activity was evaluated by allotetrahydrocortisol (alloTHF)/THF and androsterone/etiocholanolone (A/E) ratios. Delta values denoted changes during the treatment period (16 weeks--basal). Pyridostigmine growth hormone (GH) stimulation tests were performed, and testosterone (T), dihydrotestosterone (DHT), DHEA, DHEAS, adiponectin, and insulin-like growth factor I (IGF-I) were measured before and after intervention. RESULT(S): Insulin sensitivity, GH, adiponectin, and IGF-I significantly increased during pioglitazone treatment, whereas alloTHF/THF levels significantly decreased. Delta alloTHF/THF levels inversely correlated with Delta adiponectin levels. Delta A/E ratio inversely correlated with Delta IGF-I and Delta peak GH during GH stimulation tests. No significant changes were measured in T, DHT, DHEA, DHEAS, 24 h mean cortisol, or urinary excretion of steroid metabolites. CONCLUSION(S): Pioglitazone decreased relative 5alpha-reductase activity, whereas no significant changes were measured in cortisol levels or urinary cortisol excretion.


Assuntos
Hidrocortisona/metabolismo , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Síndrome do Ovário Policístico/tratamento farmacológico , Tiazolidinedionas/uso terapêutico , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Adiponectina/sangue , Androsterona/metabolismo , Glicemia/efeitos dos fármacos , Dinamarca , Etiocolanolona/metabolismo , Ácidos Graxos não Esterificados/sangue , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Hidrocortisona/urina , Insulina/sangue , Pioglitazona , Síndrome do Ovário Policístico/metabolismo , Testosterona/sangue , Tetra-Hidrocortisol/análogos & derivados , Tetra-Hidrocortisol/metabolismo , Fatores de Tempo , Resultado do Tratamento
8.
Vopr Onkol ; 53(5): 562-5, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18154121

RESUMO

The rate of DNA and protein biosynthesis in murine hepatoma HA-1 was accelerated when steroid hormones, containing a reduced delta4,3-keto group in the A-ring, were used in combination with apolipoprotein A-1. That was demonstrated for apolipoprotein A-1 complexes with dehydroepiandrosterone, dehydroepiandrosterone sulfate and tetrahydrocortisol. Apolipoprotein A-1 complexes serve as a vehicle for steroids penetration into cells to influence protein biosynthesis.


Assuntos
Apolipoproteína A-I/metabolismo , Ascite/etiologia , Carcinoma Hepatocelular/metabolismo , DNA de Neoplasias , Hormônios/metabolismo , Neoplasias Hepáticas/metabolismo , Biossíntese de Proteínas , Esteroides/metabolismo , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/genética , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona/metabolismo , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/genética , Biossíntese de Proteínas/genética , Tetra-Hidrocortisol/metabolismo
9.
Bull Exp Biol Med ; 144(3): 291-3, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18457017

RESUMO

Complexes of apolipoprotein A-I with tetrahydrocortisol and pregnenolone exhibit high biological activity and increase the rate of protein biosynthesis in the culture of rat hepatocytes. An important role in this process is played by reduced delta44-3-keto group in the A-ring of steroid hormones. A complex of apolipoprotein A-I and pregnenolone modulated the rate of protein biosynthesis in liver cells. Hence, the observed changes are not organ-specific for this steroid. Our results suggest that this mechanism of regulation play an important role in intracellular regeneration and proliferation.


Assuntos
Apolipoproteína A-I/metabolismo , Hepatócitos/fisiologia , Complexos Multiproteicos/metabolismo , Pregnenolona/metabolismo , Proteínas/metabolismo , Tetra-Hidrocortisol/metabolismo , Animais , Apolipoproteína A-I/genética , Células Cultivadas , Hepatócitos/citologia , Masculino , Pregnenolona/química , Ratos , Ratos Wistar , Tetra-Hidrocortisol/química
10.
Mol Biol (Mosk) ; 40(2): 300-9, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16637271

RESUMO

On primary culture of hepatocytes it is shown, that a complex cortisol-apolipoprotein A-I did not change rate of biosynthesis DNA and protein, whereas the complex tetrahydrocortisol-apolipoprotein A-I (THC-apoA-I) essentially raised rate of incorporation 3H-thymidine in DNA and 14C-leucine into protein. By a method of small-angle X-ray scattering it is shown, that appreciable interaction with eukariotic DNA is marked only in case of use of a complex THC-apoA-I, thus there is local fusion of DNA. The most probable region of interaction of the given complex with DNA is repetition (GCC)n the type, included in structure of many genes eukariot, including the human. It is synthesized oligonucleotid (duplex) of this type. It is shown, that at his interaction with complex THC-apoA-I there is a formation of more difficult complex, which breaks up with formation of complementary chains of oligonucleotides. The last also enter interaction with complex THC-apoA-I. It is given of kinetic this multiphasic process. Interaction of a complex cortisol-anoA-I with a duplex is less specific and does not result reduce in decay of the duplex and in formation of complementary oligonucleotides.


Assuntos
Anti-Inflamatórios/metabolismo , Apolipoproteína A-I/metabolismo , DNA/biossíntese , Hepatócitos/metabolismo , Hidrocortisona/metabolismo , Tetra-Hidrocortisol/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Apolipoproteína A-I/farmacologia , Células Cultivadas , Hepatócitos/citologia , Humanos , Hidrocortisona/farmacologia , Masculino , Oligonucleotídeos/metabolismo , Ligação Proteica , Ratos , Ratos Wistar , Tetra-Hidrocortisol/farmacologia , Repetições de Trinucleotídeos/fisiologia
11.
J Steroid Biochem Mol Biol ; 87(4-5): 309-18, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14698212

RESUMO

Tetrahydrocortisol stimulates DNA and protein biosynthesis in hepatocytes only when it enters the complex with apolipoprotein A-I. Tetrahydrocortisol-apolipoprotein A-I (THC-apoA-I) complex specifically interacts with eukaryotic DNA isolated from rat liver. In the process of interaction, rupture of hydrogen bonds between the pairs of nitrous bases occurs with the formation of single-stranded DNA structures. In such state DNA forms complexes with DNA-dependent RNA-polymerase. The most probable site of binding the tetrahydrocortisol-apolipoprotein A-I complex with DNA is the sequence of CC(GCC)(n) type entering the structure of many genes, among them the structure of human apolipoprotein A-I gene. Oligonucleotide of this type has been synthesized. Association constant (K(ass)) of it with tetrahydrocortisol-apolipoprotein A-I complex was shown to be 1.66 x 10(6)M(-1). Substitution of tetrahydrocortisol for cortisol in the complex results in a considerable decrease of K(ass). It was assumed that in the GC-pairs of the given sequence tetrahydrocortisol itself participates in the formation of hydrogen bonds with cytosine, favoring their rupture with complementary base-guanine.


Assuntos
Apolipoproteína A-I/química , Apolipoproteína A-I/metabolismo , DNA/genética , DNA/metabolismo , Tetra-Hidrocortisol/química , Tetra-Hidrocortisol/metabolismo , Animais , Apolipoproteína A-I/genética , Apolipoproteína A-I/farmacologia , Sequência de Bases , Genes , Hepatócitos/metabolismo , Humanos , Leucina/análogos & derivados , Leucina/metabolismo , Fígado/citologia , Fígado/metabolismo , Dados de Sequência Molecular , Oligonucleotídeos/química , Oligonucleotídeos/genética , Oligonucleotídeos/metabolismo , Biossíntese de Proteínas , Ratos , Ratos Wistar , Espalhamento de Radiação , Tetra-Hidrocortisol/farmacologia , Timidina/análogos & derivados , Timidina/metabolismo , Raios X
12.
J Am Soc Nephrol ; 13(10): 2540-6, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12239243

RESUMO

Reduced concentration of serum ionized calcium and increased urinary calcium excretion have been reported in primary aldosteronism and glucocorticoid-treated patients. A reduced activity of the 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta HSD2) results in overstimulation of the mineralocorticoid receptor by cortisol. Whether inhibition of the 11 beta HSD2 by glycyrrhetinic acid (GA) may increase renal calcium excretion is unknown. Serum and urinary electrolyte and creatinine, serum ionized calcium, urinary calcium excretion, and the steroid metabolites (THF+5 alpha THF)/THE as a parameter of 11 beta HSD2 activity were repeatedly measured in 20 healthy subjects during baseline conditions and during 1 wk of 500 mg/d GA. One week of GA induced a maximal increment of 93% in (THF+5 alpha THF)/THE. Ambulatory BP was significantly higher at day 7 of GA than at baseline (126/77 +/- 10/7 versus 115/73 +/- 8/6 mmHg; P < 0.001 for systolic; P < 0.05 for diastolic). During GA administration, serum ionized calcium decreased from 1.26 +/- 0.05 to 1.18 +/- 0.04 mmol/L (P < 0.0001), and absolute urinary calcium excretion was enhanced from 29.2 +/- 3.6 to 31.9 +/- 3.1 micromol/L GFR (P < 0.01). Fractional calcium excretion increased from 2.4 +/- 0.3 to 2.7 +/- 0.3% (P < 0.01) and was negatively correlated to the fractional sodium excretion during GA (R = -0.35; P < 0.001). Moreover, serum potassium correlated positively with serum ionized calcium (R = 0.66; P < 0.0001). Inhibition of 11 beta HSD2 activity is sufficient to significantly increase the fractional excretion of calcium and decrease serum ionized calcium, suggesting decreased tubular reabsorption of this divalent cation under conditions of renal glucocorticoid/mineralocorticoid excess. The likely site of steroid-regulated renal calcium handling appears to be the distal tubule.


Assuntos
Cálcio/metabolismo , Ácido Glicirretínico/farmacologia , Hidroxiesteroide Desidrogenases/metabolismo , Rim/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2 , Adulto , Pressão Sanguínea/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Potássio/sangue , Estudos Prospectivos , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisona/metabolismo
13.
Biochemistry (Mosc) ; 67(7): 790-4, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12139478

RESUMO

The in vitro effect of tetrahydrocortisol-apolipoprotein A-I complex on native adult rat liver DNA results in the formation of S1 nuclease sensitive fragments that are irregularly distributed throughout a genome. Low-angle X-ray scattering showed that after the interaction with the tetrahydrocortisol-apolipoprotein A-I complex, DNA can bind to RNA-polymerase with a high and dose-dependent cooperativity. This indicates that the effect of tetrahydrocortisol-apolipoprotein A-I complex on secondary eukaryotic DNA structure causes a local denaturation of the double helix, promoting high cooperativity of binding to RNA-polymerase. The reduced form of the hormone, tetrahydrocortisol, previously considered as an inactive metabolite, when complexed with apolipoprotein A-I, promotes a biological function similar to that of a transcription factor.


Assuntos
Apolipoproteína A-I/farmacologia , RNA Polimerases Dirigidas por DNA/metabolismo , DNA/química , DNA/metabolismo , Conformação de Ácido Nucleico/efeitos dos fármacos , Tetra-Hidrocortisol/farmacologia , Animais , Apolipoproteína A-I/metabolismo , Eletroforese em Gel de Ágar , Células Eucarióticas , Substâncias Macromoleculares , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Tetra-Hidrocortisol/metabolismo
15.
Mol Biol (Mosk) ; 36(1): 96-102, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11862720

RESUMO

The complex formed by tetrahydrocortisol (THC) and apolipoprotein A-I (ApoAI) specifically interacts with eukaryotic DNA from rat liver. Taken together, physical and chemical data and the results of small-angle X-ray scattering analysis show that interaction of the THC-ApoAI complex with eukaryotic DNA results in deformation of the DNA double helix. Single-stranded fragments were demonstrated to cause deformation of the double helix. In this state DNA forms complexes with DNA-dependent RNA polymerase. This interaction is cooperative and of saturating type; up to six enzyme molecules bind with one DNA molecule. The putative site of complex binding with DNA is the sequence CC(GCC)n found in many genes including the human ApoAI gene. An oligonucleotide of this type was synthesized. Its association constant (Ka) was 1.66 x 10(6) M-1. Substitution of THC with cortysol considerably decreases the Ka. We suggest that THC interacting with GC pairs of the binding site forms hydrogen bonds with cytosine, inducing rupture of the bonds within the complementary nucleic base pair.


Assuntos
Apolipoproteína A-I/farmacologia , DNA/química , DNA/metabolismo , Oligonucleotídeos/metabolismo , Tetra-Hidrocortisol/farmacologia , Animais , Apolipoproteína A-I/química , Apolipoproteína A-I/metabolismo , Sítios de Ligação , DNA/efeitos dos fármacos , DNA de Cadeia Simples/química , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Ratos , Ratos Wistar , Espalhamento de Radiação , Tetra-Hidrocortisol/química , Tetra-Hidrocortisol/metabolismo
16.
Bioorg Khim ; 27(2): 114-9, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11357395

RESUMO

A mechanism of activation of protein biosynthesis in hepatocytes was proposed as effected by the conditioned medium of nonparenchymal liver cells incubated in the presence of high density lypoproteins, cortisol, and lypopolysaccharides. It was found that the increase in the biosynthesis rate was associated with the formation of the tetrahydrocortisol-apolipoprotein A-I (THC-apoA-I) complex in macrophages, which display 5 alpha- and 5 beta-reductase activity and are constituents of nonparenchymal liver hepatocytes. Using the small-angle X-ray scattering technique, it was shown that the THC-apoA-I-eukaryotic DNA interaction may break hydrogen bonds between pairs of complementary nucleic bases and cause the formation of single-stranded DNA fragments capable of binding to DNA-dependent RNA polymerase. The interaction is highly cooperative and has a saturating mode, up to six enzyme molecules being bound per DNA molecule.


Assuntos
Apolipoproteína A-I/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , DNA/metabolismo , Hepatócitos/metabolismo , Tetra-Hidrocortisol/metabolismo , Animais , Apolipoproteína A-I/farmacologia , Células Cultivadas , Endotélio/citologia , Endotélio/metabolismo , Hidrocortisona/farmacologia , Células de Kupffer/metabolismo , Lipopolissacarídeos/farmacologia , Lipoproteínas HDL/farmacologia , Conformação de Ácido Nucleico , Biossíntese de Proteínas , Ratos , Ratos Wistar , Espalhamento de Radiação , Tetra-Hidrocortisol/farmacologia , Raios X
17.
Biofizika ; 45(4): 611-9, 2000.
Artigo em Russo | MEDLINE | ID: mdl-11040966

RESUMO

A biochemically active complex of apolipoprotein A-I with tetrahydrocortisol was revealed, which increases gene expression in hepatocytes. It was shown by the method of fluorescent probe that titration of rat liver DNA by the apolipoprotein A-I-tetrahydrocortisol complex leads to the appearance of single-stranded fragments. The effect of the complex on the secondary structure of native DNA was confirmed by the method of small-angle X-ray scattering. It was shown that approximately 54 apolipoprotein A-I molecules carrying tetrahydrocortisol as a ligand bind to one molecule of isolated native DNA, inducing a break of hydrogen bonds between the pair of nitrous bases. It is concluded that the cooperative effect of high-density lipoproteins and cortisol in the regulation of gene expression in hepatocytes with the participation of resident liver macrophages is accomplished by a new biochemical mechanism. This mechanism makes itself evident as a result of the interaction of DNA with the apolipoprotein A-I-tetrahydrocortisol complex, the appearance of single-stranded DNA regions in binding sites, and subsequent initiation of gene transcription.


Assuntos
Apolipoproteína A-I/metabolismo , DNA/metabolismo , Tetra-Hidrocortisol/metabolismo , Animais , Apolipoproteína A-I/química , DNA/química , Feminino , Ligação de Hidrogênio , Fígado/citologia , Fígado/metabolismo , Ligação Proteica , Ratos , Ratos Wistar , Espalhamento de Radiação , Tetra-Hidrocortisol/química
18.
Steroids ; 65(2): 89-97, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10639020

RESUMO

This study describes a new approach using stable isotope methodology in evaluating 11beta-HSD activities in vivo based on urinary excretion of cortisol, cortisone, and their A-ring reduced metabolites. The method involved the measurement of deuterium-labeled cortisol and its deuterium-labeled metabolites by GC/MS simultaneously with endogenous cortisol, cortisone, and their A-ring reduced metabolites after oral administration of deuterium-labeled cortisol to normal human subjects. This stable isotope approach offered unique advantages in assessing the appropriateness of measuring unconjugated and total (unconjugated + conjugated) cortisol, cortisone, and their A-ring reduced metabolites in urine as indices of renal 11beta-HSD2 activity in man. Our results strongly support that the measurement of urinary unconjugated cortisol and cortisone is a significant advance in assessing 11beta-HSD2 activity.


Assuntos
Deutério , Hidrocortisona , Hidroxiesteroide Desidrogenases/metabolismo , Rim/enzimologia , 11-beta-Hidroxiesteroide Desidrogenases , Adulto , Cortisona/metabolismo , Cortisona/urina , Deutério/administração & dosagem , Deutério/metabolismo , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/metabolismo , Rim/metabolismo , Masculino , Espectrometria de Massas , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/metabolismo , Tetra-Hidrocortisona/urina , Fatores de Tempo
19.
Steroids ; 65(2): 98-102, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10639021

RESUMO

Oral dehydroepiandrosterone (DHEA) replacement therapy may have a multitude of potential beneficial effects and exerts its action mainly via peripheral bioconversion to androgens (and estrogens). A daily dose of 50-mg DHEA has been shown by us and others to restore low endogenous serum DHEA concentrations to normal youthful levels followed by an increase in circulating androgens and estrogens. As the hepatic first-pass effect may lead to a non physiological metabolism of DHEA after oral ingestion we studied the influence of two single DHEA doses (50 and 100 mg) on the excretion of steroid metabolites in 14 elderly males [age 58.8+/-5.1 years (mean +/- SEM)] with endogenous DHEAS levels <1500 ng/ml and in 9 healthy females (age 23.3+/-4.1 years) with transient suppression of endogenous DHEA secretion induced by dexamethasone (dex) pretreatment (4x0.5 mg/day/4 days). Urinary steroid profiles in the elderly males were compared to the steroid patterns found in 15 healthy young men (age 28.9+/-5.1 years). In the females the results were compared to their individual baseline excretion without dex pretreatment. Urinary steroid determinations were carried out by semiautomatic capillary gas-liquid chromatography. In both genders DHEA administration induced significant increases in urinary DHEA (females: baseline vs. 50 mg vs. 100 mg: 361+/-131 vs. 510+/-264 vs. 1541+/-587 microg/day; males: placebo vs. 50 mg vs. 100 mg: 434+/-154 vs. 1174+/-309 vs. 4751+/-1059 microg/day) as well as in the major DHEA metabolites androsterone (A) and etiocholanolone (Et). Fifty mg DHEA led to an excretion of DHEA and its metabolites only slightly above baseline levels found in young females and in young men, respectively, whereas 100 mg induced clearly supraphysiological values. After 50 mg DHEA the ratios of urinary DHEA metabolites (A/DHEA, Et/DHEA) were not significantly different between elderly males vs. young male volunteers and young healthy females versus their individual baseline levels. In conclusion, an oral dose of 30 to 50 mg DHEA restores a physiological urinary steroid profile in subjects with DHEA deficiency without evidence for a relevant hepatic first-pass effect on urinary metabolites.


Assuntos
Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/metabolismo , Administração Oral , Adulto , Androgênios/metabolismo , Androgênios/farmacocinética , Androgênios/urina , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/metabolismo , Tetra-Hidrocortisona/urina
20.
J Clin Endocrinol Metab ; 84(11): 4172-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566668

RESUMO

The interconversion of hormonally active cortisol (F) and inactive cortisone (E) is catalyzed by two isozymes of 11beta-hydroxysteroid dehydrogenase (11betaHSD), an oxo-reductase converting E to F (11betaHSD1) and a dehydrogenase (11betaHSD2) converting F to E. 11betaHSD1 is important in mediating glucocorticoid-regulated glucose homeostasis and regional adipocyte differentiation. Earlier studies conducted with GH-deficient subjects treated with replacement GH suggested that GH may modulate 11betaHSD1 activity. In 7 acromegalic subjects withdrawing from medical therapy (Sandostatin-LAR; 20-40 mg/month for at least 12 months), GH rose from 7.1 +/- 1.5 to 17.5 +/- 4.3 mU/L (mean +/- SE), and insulin-like growth factor I (IGF-I) rose from 43.0 +/- 8.8 to 82.1 +/- 13.7 nmol/L (both P < 0.05) 4 months after treatment. There was a significant alteration in the normal set-point of F to E interconversion toward E. The fall in the urinary tetrahydrocortisols/tetrahydocortisone ratio (THF+allo-THF/THE; 0.82 +/- 0.06 to 0.60 +/- 0.06; P < 0.02) but unaltered urinary free F/urinary free E ratio (a marker for 11betaHSD2 activity) suggested that this was due to inhibition of 11betaHSD1 activity. An inverse correlation between GH and the THF+allo-THF/THE ratio was observed (r = -0.422; P < 0.05). Conversely, in 12 acromegalic patients treated by transsphenoidal surgery (GH falling from 124 +/- 49.2 to 29.3 +/- 15.4 mU/L; P < 0.01), the THF+allo-THF/THE ratio rose from 0.53 +/- 0.06 to 0.63 +/- 0.07 (P < 0.05). Patients from either group who failed to demonstrate a change in GH levels showed no change in the THF+allo-THF/THE ratio. In vitro studies conducted on cells stably transfected with either the human 11betaHSD1 or 11betaHSD2 complementary DNA and primary cultures of human omental adipose stromal cells expressing only the 11betaHSD1 isozyme indicated a dose-dependent inhibition of 11betaHSD1 oxo-reductase activity with IGF-I, but not GH. Neither IGF-I nor GH had any effect on 11betaHSD2 activity. GH, through an IGF-I-mediated effect, inhibits 11betaHSD1 activity. This reduction in E to F conversion will increase the MCR of F, and care should be taken to monitor the adequacy of function of the hypothalamo-pituitary-adrenal axis in acromegalic subjects and in GH-deficient, hypopituitary patients commencing replacement GH therapy. Conversely, enhanced E to F conversion occurs with a reduction in GH levels; in liver and adipose tissue this would result in increased hepatic glucose output and visceral adiposity, suggesting that part of the phenotype currently attributable to adult GH deficiency may be an indirect consequence of its effect on tissue F metabolism via 11betaHSD1 expression.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Hidroxiesteroide Desidrogenases/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Isoenzimas/metabolismo , 11-beta-Hidroxiesteroide Desidrogenases , Acromegalia/tratamento farmacológico , Acromegalia/metabolismo , Acromegalia/cirurgia , Tecido Adiposo/enzimologia , Adulto , Idoso , Diferenciação Celular , Linhagem Celular , Feminino , Hormônio do Crescimento Humano/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Rim/enzimologia , Masculino , Pessoa de Meia-Idade , Octreotida/administração & dosagem , Adeno-Hipófise/cirurgia , Células Estromais/enzimologia , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisona/metabolismo
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