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1.
Br J Clin Pharmacol ; 90(1): 247-263, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37574850

RESUMO

AIMS: Abiraterone acetate, a prodrug of abiraterone (ABI), provides an efficient therapeutic option for metastatic castration-resistant prostate cancer patients. ABI undergoes extensive metabolism in vivo and is transformed into active metabolites Δ4 -abiraterone and 3-keto-5α-abiraterone as well as inactive metabolites abiraterone sulfate and abiraterone N-oxide sulfate. We aimed to examine the effect of polymorphisms in SLCO2B1, CYP3A4 and UGT1A4 on the pharmacokinetics of ABI and its metabolites. METHODS: In this study, 81 healthy Chinese subjects were enrolled and divided into 2 groups for fasted (n = 45) and fed (n = 36) studies. Plasma samples were collected after administering a 250 mg abiraterone acetate tablet followed by liquid chromatography-tandem mass spectrometry analysis. Genotyping was performed on a MassARRAY system. The association between SLCO2B1, CYP3A4, UGT1A4 genotype and pharmacokinetic parameters of ABI and its metabolites was assessed. RESULTS: Food effect study demonstrated high fat meal remarkedly increased systemic exposure of ABI and its metabolites. The geometric mean ratio and 90% confidence interval of area under the plasma concentration-time curve from time 0 to the time of the last quantifiable concentration (AUC0-t ) and maximum plasma concentration (Cmax ) of ABI in fed state vs. fasted state were 351.64% (286.86%-431.04%) and 478.45% (390.01%-586.94%), respectively, while the corresponding results were ranging from 145.11% to 269.42% and 150.10% to 478.45% for AUC0-t and Cmax of ABI metabolites in fed state vs. fasted state, respectively. The SLCO2B1 rs1077858 had a significant influence on AUC0-t and Cmax , while 7 other SLCO2B1 variants prolonged half-life of ABI under both fasted and fed conditions. As for ABI metabolites, the systemic exposure of Δ4 -abiraterone, abiraterone sulfate and abiraterone N-oxide sulfate as well as the elimination of 3-keto-5α-abiraterone were significantly affected by SLCO2B1 polymorphisms. Polymorphisms in CYP3A4 and UGT1A4 did not significantly affect pharmacokinetics of ABI and its metabolites. CONCLUSION: Polymorphisms in SLCO2B1 were significantly related to the pharmacokinetic variability of ABI and its metabolites under both fasted and fed conditions.


Assuntos
Androstenos , Citocromo P-450 CYP3A , Transportadores de Ânions Orgânicos , Farmacocinética , Androstenos/metabolismo , Androstenos/farmacocinética , Humanos , Transportadores de Ânions Orgânicos/genética , Citocromo P-450 CYP3A/genética , Glucuronosiltransferase/genética , Neoplasias da Próstata , Polimorfismo de Nucleotídeo Único , População do Leste Asiático , Masculino , Voluntários , Adulto , Jejum , Alimentos
2.
Steroids ; 162: 108693, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32645328

RESUMO

The interactions of pharmacologically active 3-keto-Δ4-metabolite of anticancer drug abiraterone (D4A) with steroid-metabolizing cytochromes P450 (CYP51A1, CYP11A1, CYP19A1) was studied by absorption spectroscopy and molecular docking. Both abiraterone and D4A induce type I spectral changes of CYP51A1, one of the enzymes of cholesterol biosynthesis. We have revealed that D4A did not induce spectral changes of CYP11A1, the key enzyme of pregnenolone biosynthesis, unlike abiraterone (type II ligand of CYP11A1). On the contrary, D4A interacts with the active site of CYP19A1, the key enzyme of estrogen biosynthesis, inducing type II spectral changes, while abiraterone does not. Spectral analysis allowed us to calculate spectral dissociation constant (KS) for each complex of cytochrome P450 with respective ligands. The data were supported by molecular docking. The obtained results broaden understanding of interactions of D4A with some of the key steroid-metabolizing cytochromes P450 and allow one to predict possible disproportions of steroid metabolism.


Assuntos
Androstenos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Simulação de Acoplamento Molecular , Sistema Enzimático do Citocromo P-450/química , Ligação Proteica , Conformação Proteica , Análise Espectral
3.
Bioorg Chem ; 100: 103957, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32470763

RESUMO

Binding of toxic ligands to DNA could result in undesirable biological processes, such as carcinogenesis or mutagenesis. Binding mode of Abiraterone (ABR), a steroid drug and calf thymus DNA (ctDNA) was investigated in this study using fluorescence and ultraviolet-visible spectroscopy. The probable prediction of binding and the type of interaction forces involved in the arrangement between ABR and ctDNA were explored through spectroscopic and molecular docking studies. The results indicated that ABR binds to the ctDNA in the minor groove. The binding constants were in the range of 1.35 × 106-0.36 × 106 L mol-1 at the studied temperatures. Fluorescence and spectrophotometric data suggested static quenching between ctDNA and ABR. The endothermic values of thermodynamic parameters ΔH°=-82.84 kJ mol-1; ΔS°=-161 J mol-1K-1 suggested that hydrogen bonding is the main force involved in binding of ABR with ctDNA. In experimental studies, the free binding energy at 298 K was -34.9 kJ mol-1 with the relative binding energy ≈ -29.65 kJ mol-1 of docked structure. The Ksv obtained for ABR-KI was similar to that for ABR- ctDNA -KI demonstrating no protection by ctDNA against quenching effect of KI. Thus, suggesting involvement of groove binding between ABR and ctDNA. No change in the fluorescence intensity of ABR-ctDNA was observed in presence of NaCl. Thus, ruling out the involvement of electrostatic interaction. These studies could serve as new insights in understanding the mechanisms of toxicity, resistance and side effects of ABR.


Assuntos
Androstenos/química , DNA/química , Simulação de Acoplamento Molecular , Androstenos/metabolismo , Animais , Sítios de Ligação , Bovinos , Dicroísmo Circular , DNA/metabolismo , Etídio/química , Etídio/metabolismo , Concentração Osmolar , Espectrometria de Fluorescência , Espectrofotometria , Termodinâmica
4.
Biomed Res Int ; 2020: 9710421, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32337286

RESUMO

BACKGROUND: The molecular mechanisms and genetic markers of thyroid cancer are unclear. In this study, we used bioinformatics to screen for key genes and pathways associated with thyroid cancer development and to reveal its potential molecular mechanisms. METHODS: The GSE3467, GSE3678, GSE33630, and GSE53157 expression profiles downloaded from the Gene Expression Omnibus database (GEO) contained a total of 164 tissue samples (64 normal thyroid tissue samples and 100 thyroid cancer samples). The four datasets were integrated and analyzed by the RobustRankAggreg (RRA) method to obtain differentially expressed genes (DEGs). Using these DEGs, we performed gene ontology (GO) functional annotation, pathway analysis, protein-protein interaction (PPI) analysis and survival analysis. Then, CMap was used to identify the candidate small molecules that might reverse thyroid cancer gene expression. RESULTS: By integrating the four datasets, 330 DEGs, including 154 upregulated and 176 downregulated genes, were identified. GO analysis showed that the upregulated genes were mainly involved in extracellular region, extracellular exosome, and heparin binding. The downregulated genes were mainly concentrated in thyroid hormone generation and proteinaceous extracellular matrix. Pathway analysis showed that the upregulated DEGs were mainly attached to ECM-receptor interaction, p53 signaling pathway, and TGF-beta signaling pathway. Downregulation of DEGs was mainly involved in tyrosine metabolism, mineral absorption, and thyroxine biosynthesis. Among the top 30 hub genes obtained in PPI network, the expression levels of FN1, NMU, CHRDL1, GNAI1, ITGA2, GNA14 and AVPR1A were associated with the prognosis of thyroid cancer. Finally, four small molecules that could reverse the gene expression induced by thyroid cancer, namely ikarugamycin, adrenosterone, hexamethonium bromide and clofazimine, were obtained in the CMap database. CONCLUSION: The identification of the key genes and pathways enhances the understanding of the molecular mechanisms for thyroid cancer. In addition, these key genes may be potential therapeutic targets and biomarkers for the treatment of thyroid cancer.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional , Bases de Dados Genéticas , Marcadores Genéticos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Androstenos/metabolismo , Clofazimina/metabolismo , Exossomos/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Heparina/metabolismo , Hexametônio/metabolismo , Humanos , Lactamas/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Prognóstico , Mapas de Interação de Proteínas/genética , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo , Transdução de Sinais , Hormônios Tireóideos/metabolismo , Transcriptoma , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Tirosina/metabolismo
5.
Chem Commun (Camb) ; 56(11): 1733-1736, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31938799

RESUMO

We report here that pregnenolonyl-α-glucoside (2), a steryl glycoside synthesized directly from pregnenolone and glucose via a consecutive multienzyme-catalyzed process, exhibits marked dose-dependent cytotoxic activity against HT29, AGS, and ES-2 cells with IC50 values of 23.5 to 50.9 µM. An in vitro CYP17A1 binding pattern assay and protein-ligand docking model support that 2, like abiraterone, binds in the active site heme iron pocket of CYP17A1.


Assuntos
Antineoplásicos/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Glucosídeos/farmacologia , Pregnenolona/análogos & derivados , Pregnenolona/farmacologia , Androstenos/metabolismo , Androstenos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Bactérias/enzimologia , Domínio Catalítico , Linhagem Celular Tumoral , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/metabolismo , Glucosídeos/síntese química , Glucosídeos/metabolismo , Glicosilação , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Pregnenolona/metabolismo , Ligação Proteica
6.
Drug Metab Dispos ; 48(2): 75-84, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31727674

RESUMO

Abiraterone (Abi) acetate (AA) is a prodrug of Abi, a CYP17A1 inhibitor used to treat patients with advanced prostate cancer. Abi is a selective steroidal inhibitor that blocks the biosynthesis of androgens. It undergoes extensive biotransformation by steroid pathways, leading to the formation of pharmacologically active Δ4-Abi (D4A) and 5α-Abi. This study aimed to characterize the glucuronidation pathway of Abi and its two active metabolites. We show that Abi, its metabolites, and another steroidal inhibitor galeterone (Gal) undergo secondary metabolism to form glucuronides (G) in human liver microsomes with minor formation by intestine and kidney microsomal preparations. The potential clinical relevance of this pathway is supported by the detection by liquid chromatography-tandem mass spectrometry of Abi-G, D4A-G, and 5α-Abi-G in patients under AA therapy. A screening of UGT enzymes reveals that UGT1A4 is the main enzyme involved. This is supported by inhibition experiments using a selective UGT1A4 inhibitor hecogenin. A number of common and rare nonsynonymous variants significantly abrogate the UGT1A4-mediated formation of Abi-G, D4A-G, and 5α-Abi-G in vitro. We also identify Gal, Abi, and its metabolites as highly potent inhibitors of steroid inactivation by the UGT pathway with submicromolar inhibitor constant values. They reduce the glucuronidation of both the adrenal precursors and potent androgens in human liver, prostate cancer cells, and by recombinant UGTs involved in their inactivation. In conclusion, tested CYP17A1 inhibitors are metabolized through UGT1A4, and germline variations affecting this metabolic pathway may also influence drug metabolism. SIGNIFICANCE STATEMENT: The antiandrogen abiraterone (Abi) is a selective steroidal inhibitor of the cytochrome P450 17α-hydroxy/17,20-lyase, an enzyme involved in the biosynthesis of androgens. Abi is metabolized to pharmacologically active metabolites by steroidogenic enzymes. We demonstrate that Abi and its metabolites are glucuronidated in the liver and that their glucuronide derivatives are detected at variable levels in circulation of treated prostate cancer patients. UDP-glucuronosyltransferase (UGT)1A4 is the primary enzyme involved, and nonsynonymous germline variations affect this metabolic pathway in vitro, suggesting a potential influence of drug metabolism and action in patients. Their inhibitory effect on drug and steroid glucuronidation raises the possibility that these pharmacological compounds might affect the UGT-associated drug-metabolizing system and pre-receptor control of androgen metabolism in patients.


Assuntos
Androstenos/metabolismo , Androstenos/farmacologia , Glucuronídeos/metabolismo , Glucuronosiltransferase/metabolismo , Esteroides/metabolismo , Androgênios/metabolismo , Cromatografia Líquida/métodos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Neoplasias/metabolismo , Sapogeninas/metabolismo , Sapogeninas/farmacologia , Espectrometria de Massas em Tandem/métodos
7.
Nat Commun ; 10(1): 2452, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31165728

RESUMO

3-ß-hydroxysteroid-Δ8, Δ7-isomerase, known as Emopamil-Binding Protein (EBP), is an endoplasmic reticulum membrane protein involved in cholesterol biosynthesis, autophagy, oligodendrocyte formation. The mutation on EBP can cause Conradi-Hunermann syndrome, an inborn error. Interestingly, EBP binds an abundance of structurally diverse pharmacologically active compounds, causing drug resistance. Here, we report two crystal structures of human EBP, one in complex with the anti-breast cancer drug tamoxifen and the other in complex with the cholesterol biosynthesis inhibitor U18666A. EBP adopts an unreported fold involving five transmembrane-helices (TMs) that creates a membrane cavity presenting a pharmacological binding site that accommodates multiple different ligands. The compounds exploit their positively-charged amine group to mimic the carbocationic sterol intermediate. Mutagenesis studies on specific residues abolish the isomerase activity and decrease the multidrug binding capacity. This work reveals the catalytic mechanism of EBP-mediated isomerization in cholesterol biosynthesis and how this protein may act as a multi-drug binder.


Assuntos
Androstenos/metabolismo , Anticolesterolemiantes/metabolismo , Antagonistas de Estrogênios/metabolismo , Esteroide Isomerases/metabolismo , Tamoxifeno/metabolismo , Colesterol/biossíntese , Condrodisplasia Punctata , Resistencia a Medicamentos Antineoplásicos , Humanos , Simulação de Acoplamento Molecular , Mutagênese , Ligação Proteica , Estrutura Terciária de Proteína , Esteroide Isomerases/ultraestrutura
8.
J Steroid Biochem Mol Biol ; 189: 116-126, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30825506

RESUMO

The 11ß-hydroxysteroid dehydrogenase (11ßHSD) types 1 and 2 are primarily associated with glucocorticoid inactivation and reactivation. Several adrenal C11-oxy C19 and C11-oxy C21 steroids, which have been identified in prostate cancer, 21-hydroxylase deficiency and polycystic ovary syndrome, are substrates for these isozymes. This study describes the kinetic parameters of 11ßHSD1 and 11ßHSD2 towards the C11-keto and C11-hydroxy derivatives of the C19 and C21 steroids. The apparent Km and Vmax values indicate the more prominent 11ßHSD2 activity towards 11ß-hydroxy androstenedione, 11ß-hydroxytestosterone and 11ß-hydroxyprogesterone in contrast to the 11ßHSD1 reduction of the C11-keto steroids, as was demonstrated in the LNCaP cell model in the production of 11-ketotestosterone and 11-ketodihydrotestosterone. Data highlighted the role of 11ßHSD2 and cytochrome P450 17A1 in the contribution of C11-oxy C21 steroids to the C11-oxy C19 steroid pool in the C11-oxy backdoor pathway. In addition, 11ßHSD2 activity, catalysing 11-ketotestosterone biosynthesis, was shown to be key in the production of prostate specific antigen and in the progression of prostate cancer to castration resistant prostate cancer. The study at hand thus provides evidence that 11ßHSD isozymes play key roles in pathophysiological states, more so than was previously put forward.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Androstenos/metabolismo , Progesterona/análogos & derivados , Testosterona/análogos & derivados , Vias Biossintéticas , Linhagem Celular Tumoral , Células HEK293 , Humanos , Masculino , Progesterona/metabolismo , Neoplasias da Próstata/metabolismo , Isoformas de Proteínas/metabolismo , Especificidade por Substrato , Testosterona/metabolismo
9.
J Med Chem ; 61(11): 4946-4960, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29792703

RESUMO

Inhibition of androgen biosynthesis is clinically effective for treating androgen-responsive prostate cancer. Abiraterone is a clinical first-in-class inhibitor of cytochrome P450 17A1 (CYP17A1) required for androgen biosynthesis. However, abiraterone also causes hypertension, hypokalemia, and edema, likely due in part to off-target inhibition of another steroidogenic cytochrome P450, CYP21A2. Abiraterone analogs were designed based on structural evidence that B-ring substituents may favorably interact with polar residues in binding CYP17A1 and sterically clash with residues in the CYP21A2 active site. The best analogs increased selectivity of CYP17A1 inhibition up to 84-fold compared with 6.6-fold for abiraterone. Cocrystallization with CYP17A1 validated the intended new contacts with CYP17A1 active site residues. Docking these analogs into CYP21A2 identified steric clashes that likely underlie decreased binding and CYP21A2 inhibition. Overall, these analogs may offer a clinical advantage in the form of reduced side effects.


Assuntos
Androstenos/química , Androstenos/farmacologia , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacologia , Desenho de Fármacos , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Esteroide 21-Hidroxilase/antagonistas & inibidores , Androstenos/metabolismo , Domínio Catalítico , Inibidores das Enzimas do Citocromo P-450/metabolismo , Humanos , Simulação de Acoplamento Molecular , Esteroide 17-alfa-Hidroxilase/química , Esteroide 17-alfa-Hidroxilase/metabolismo , Esteroide 21-Hidroxilase/química , Esteroide 21-Hidroxilase/metabolismo
10.
J Pharm Biomed Anal ; 154: 66-74, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29533860

RESUMO

Abiraterone acetate is administered as a prodrug to patients with metastatic, castration-resistant prostate cancer (mCRPC) and is readily metabolized into the potent 17a-hydroxylase/17,20-lyase (CYP17) enzyme inhibitor and androgen receptor inhibitor abiraterone and Δ(4)-abiraterone (D4A), respectively. To investigate pharmacokinetic variability in abiraterone acetate metabolism we developed highly sensitive liquid chromatography/mass spectrometry (LC/MS) assays for the simultaneous quantitation of abiraterone and D4A in human plasma using high-resolution mass spectrometry (HRMS) on an Orbitrap mass spectrometer. This study demonstrates the quantitative performance of HRMS and compares the conventional Parallel Reaction Monitoring (PRM) mode of quantitation with the unconventional Full scan MS mode conducted at high resolution (>70,000 resolution). The use of HRMS for quantitation of abiraterone and D4A yielded assays that were linear over a broad concentration range (0.074-509.6 ng/mL for abiraterone; 0.075-59.93 ng/mL for D4A) in both Full scan MS and PRM modes. The assay precision for abiraterone and D4A was below 5% in PRM mode and 7% in Full scan MS mode. Accuracies fell within 98-107% for abiraterone and 104-112% for D4A in PRM mode, and 96-116% for abiraterone and 96-105% for D4A in Full scan MS mode, each meeting the acceptance criteria of FDA approved guidelines for bioanalytical methods The PRM analysis of abiraterone and D4A provided high specificity and reduced background interference, however the Full scan MS detection at a resolution of 70,000 was advantageous in that it required minimal optimization, was simple to implement, yielded comparable quantitative characteristics to PRM and the data is useful for re-analysis. Use of the assays were demonstrated for quantitation of these metabolites in steady state trough level plasma of seventeen (17) patients with mCRPC, demonstrating the inter-patient variability of up to 10-fold concentration.


Assuntos
Antagonistas de Receptores de Andrógenos/sangue , Androstenos/sangue , Antineoplásicos/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Antagonistas de Receptores de Andrógenos/análise , Antagonistas de Receptores de Andrógenos/farmacocinética , Androstenos/metabolismo , Androstenos/farmacocinética , Androstenos/uso terapêutico , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Variação Biológica da População , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Masculino , Pró-Fármacos/análise , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacocinética , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/patologia , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
11.
Animal ; 12(3): 648-656, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28803576

RESUMO

In order to accurately estimate body composition at slaughter and to meet specific market targets, the influence of age at time of castration (surgical or immunological) on body composition and boar taint indicators must be determined for male pigs. In all, 48 males were randomly assigned to one of four management regimens: (1) entire male pigs (EM), (2) EM surgically castrated at ~40 kg BW and 10 weeks of age (late castrates; LC), (3) conventional, early surgical castrates (within 4 days of birth; EC) and (4) EM immunized with a gonadotropin-releasing hormone (GnRH) analog (primary dose at 30 kg BW and 8 weeks of age; booster dose at 70 kg and 14 weeks of age; IM). Pigs were fed corn and soybean meal-based diets that were not limiting in essential nutrients. Back fat was sampled on days -3, 8, 18 and 42, relative to administering the booster dose of GnRH analog at day 0, to determine androstenone concentrations (n=8 or 9/group). Fat androstenone concentrations in IM were lower than EM between days 8 and 42 after administering the booster dose (173 v. 863 ng/g, respectively; P<0.01), and were not different from surgically castrated males (EC and LC) after day 18. Slaughter occurred at ~115 kg BW, 42 days (6 weeks) after administering the booster dose for IM, and 10 and 20 weeks after surgical castration for LC and EC, respectively (n=8 or 9/group). At slaughter, live BW, liver weight as a percent of live BW, dissectible bone as a percent of cold carcass side, body protein and water contents and whole-body protein deposition decreased with time after surgical castration (linear; P<0.05), whereas dressing percentage, dissectible fat, probe fat depth and body fat content increased with time after surgical castration (linear; P<0.05). The IM had intermediate dressing percentage and dissected fat to EM and EC, whereas liver weight as a percent of live BW and body protein and lipid contents were not different from EM. Whole-body lipid deposition tended to be greater in IM than in EM between 14 and 20 weeks of age (373 v. 286 g/d; P=0.051). In conclusion, castration of male pigs after 6 weeks of age has a lasting effect on physical and chemical body composition. The relationship between time after castration and body composition may be developed to predict carcass composition and can be used to determine the ideal immunization schedule aimed at specific markets in the future.


Assuntos
Carne/normas , Suínos/fisiologia , Tecido Adiposo/metabolismo , Androstenos/metabolismo , Animais , Composição Corporal/fisiologia , Dieta/veterinária , Hormônio Liberador de Gonadotropina/imunologia , Imunização/veterinária , Masculino , Orquiectomia/efeitos adversos , Distribuição Aleatória
12.
Molecules ; 22(9)2017 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-28891949

RESUMO

The catalytic activity of enzymes produced by an entomopathogenic filamentous fungus (Isaria fumosorosea KCh J2) towards selected steroid compounds (androstenedione, adrenosterone, progesterone, 17α-methyltestosterone and dehydroepiandrosterone) was investigated. All tested substrates were efficiently transformed. The structure of the substrate has a crucial impact on regio- and stereoselectivity of hydroxylation since it affects binding to the active site of the enzyme. Androstenedione was hydroxylated in the 7α-position to give a key intermediate in the synthesis of the diuretic-7α-hydroxyandrost-4-ene-3,17-dione with 82% conversion. Adrenosterone and 17α-methyltestosterone were hydroxylated in the 6ß-position. Hydroxylated derivatives such as 15ß-hydroxy-17α-methyltestosterone and 6ß,12ß-dihydroxy-17α-methyltestosterone were also observed. In the culture of Isaria fumosorosea KCh J2, DHEA was effectively hydroxylated in the C-7 position and then oxidized to give 7-oxo-DHEA, 3ß,7α- and 3ß,7ß-dihydroxy-17a-oxa-d-homo-androst-5-ene-17-one. We obtained 7ß-OH-DHEA lactone with 82% yield during 3 days transformation of highly concentrated (5 g/L) DHEA.


Assuntos
Androstenodiona/metabolismo , Androstenos/metabolismo , Cordyceps/enzimologia , Desidroepiandrosterona/metabolismo , Metiltestosterona/metabolismo , Progesterona/metabolismo , Animais , Biocatálise , Biotransformação , Cordyceps/isolamento & purificação , Proteínas Fúngicas/metabolismo , Hidroxilação , Lactonas/metabolismo , Estrutura Molecular , Aranhas/microbiologia , Especificidade por Substrato
13.
Ther Drug Monit ; 39(3): 243-251, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28490047

RESUMO

BACKGROUND: Abiraterone acetate and enzalutamide are 2 novel drugs for the treatment of metastatic castration-resistant prostate cancer. The metabolism of these drugs is extensive. Major metabolites are N-desmethyl enzalutamide, enzalutamide carboxylic acid, abiraterone N-oxide sulfate, and abiraterone sulfate; of which N-desmethyl enzalutamide is reported to possess antiandrogen capacities. A liquid chromatography-tandem mass spectrometry method for simultaneous quantification of abiraterone, enzalutamide, and the main metabolites has been developed and validated to support therapeutic drug monitoring. METHODS: Human plasma samples of patients treated with abiraterone or enzalutamide were harvested at the clinic and stored at -20°C. Proteins were precipitated by acetonitrile, and the final extract was injected on a Kinetex C18 column and separated with gradient elution. Analytes were detected by liquid chromatography-mass spectrometry (Triple Quad 6500). RESULTS: The method was validated over various linear ranges: 1-100 ng/mL for abiraterone, 5-500 ng/mL for enzalutamide and enzalutamide carboxylic acid, 10-1000 ng/mL for N-desmethyl enzalutamide, 30-3000 ng/mL for abiraterone N-oxide sulfate, and 100-10,000 ng/mL for abiraterone sulfate. Intra-assay and interassay variabilities were within ±15% of the nominal concentrations for quality control samples at medium and high concentrations and within ±20% at the lower limit of quantification, respectively. CONCLUSIONS: The described method for simultaneous determination of abiraterone and enzalutamide was validated successfully and provides a useful tool for therapeutic drug monitoring in patients treated with these agents.


Assuntos
Androstenos/sangue , Androstenos/metabolismo , Cromatografia Líquida/métodos , Feniltioidantoína/análogos & derivados , Plasma/química , Espectrometria de Massas em Tandem/métodos , Benzamidas , Monitoramento de Medicamentos/métodos , Humanos , Nitrilas , Feniltioidantoína/sangue , Feniltioidantoína/metabolismo , Reprodutibilidade dos Testes
14.
J Clin Endocrinol Metab ; 102(8): 2701-2710, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472487

RESUMO

Context: Patients with 21-hydroxylase deficiency (21OHD) have long-term complications, resulting from poor disease control and/or glucocorticoid overtreatment. Lack of optimal biomarkers has made it challenging to tailor therapy and predict long-term outcomes. Objective: To identify biomarkers of disease control and long-term complications in 21OHD. Setting and Participants: Cross-sectional study of 114 patients (70 males), ages 2 to 67 years (median, 15 years), seen in a tertiary referral center. Methods: We correlated a mass-spectrometry panel of 23 steroids, obtained before first morning medication, with bone age advancement (children), adrenal volume (adults), testicular adrenal rest tumors (TART), hirsutism, menstrual disorders, and pituitary hormones. Results: Total adrenal volume correlated positively with 18 steroids, most prominently 21-deoxycortisol and four 11-oxygenated-C19 (11oxC19) steroids: 11ß-hydroxyandrostenedione (11OHA4), 11-ketoandrostenedione (11ketoA4), 11ß-hydroxytestosterone (11OHT), and 11-ketotestosterone (11ketoT) (r ≈ 0.7, P < 0.0001). Nine steroids were significantly higher (P ≤ 0.01) in males with TART compared with those without TART, including 11OHA4 (6.8-fold), 11OHT (4.9-fold), 11ketoT (3.6-fold), 11ketoA4 (3.3-fold), and pregnenolone sulfate (PregS; 4.8-fold). PregS (28.5-fold) and 17-hydroxypregnenolone sulfate (19-fold) levels were higher (P < 0.01) in postpubertal females with menstrual disorders. In males, testosterone levels correlated positively with all 11oxC19 steroids in Tanner stages 1 and 2 (r ≈ 0.7; P < 0.001) but negatively in Tanner stage 5 (r = -0.3 and P < 0.05 for 11ketoA4 and 11ketoT). In females, testosterone level correlated positively with all four 11oxC19 steroids across all Tanner stages (r ≈ 0.8; P < 0.0001). Conclusion: 11oxC19 steroids and PregS might serve as clinically useful biomarkers of disease control and long-term complications in 21OHD.


Assuntos
Hiperplasia Suprarrenal Congênita/metabolismo , Tumor de Resto Suprarrenal/metabolismo , Androgênios/metabolismo , Hirsutismo/metabolismo , Distúrbios Menstruais/metabolismo , Neoplasias Testiculares/metabolismo , 17-alfa-Hidroxipregnenolona/análogos & derivados , 17-alfa-Hidroxipregnenolona/metabolismo , Adolescente , Glândulas Suprarrenais/patologia , Adulto , Determinação da Idade pelo Esqueleto , Idoso , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Androstenos/metabolismo , Criança , Pré-Escolar , Cortodoxona/metabolismo , Estudos Transversais , Feminino , Humanos , Hidroxitestosteronas/metabolismo , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pregnenolona/metabolismo , Testosterona/análogos & derivados , Testosterona/metabolismo , Adulto Jovem
15.
Chem Biol Interact ; 276: 167-173, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28257955

RESUMO

Carbonyl reduction is an important metabolic pathway for endogenous and xenobiotic substances. The tobacco specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, nicotine-derived nitrosamine ketone) is classified as carcinogenic to humans (IARC, Group 1) and considered to play the most important role in tobacco-related lung carcinogenesis. Detoxification of NNK through carbonyl reduction is catalyzed by members of the AKR- and the SDR-superfamilies which include AKR1B10, AKR1C1, AKR1C2, AKR1C4, 11ß-HSD1 and CBR1. Because some reductases are also involved in steroid metabolism, five different hormones were tested for their inhibitory effect on NNK carbonyl reduction. Two of those hormones were estrogens (estradiol and ethinylestradiol), another two hormones belong to the gestagen group (progesterone and drospirenone) and the last tested hormone was an androgen (testosterone). Furthermore, one of the estrogens (ethinylestradiol) and one of the gestagens (drospirenone) are synthetic hormones, used as hormonal contraceptives. Five of six NNK reducing enzymes (AKR1B10, AKR1C1, AKR1C2, AKR1C4 and 11ß-HSD1) were significantly inhibited by the tested sex hormones. Only NNK reduction catalyzed by CBR1 was not significantly impaired. In the case of the other five reductases, gestagens had remarkably stronger inhibitory effects at a concentration of 25 µM (progesterone: 66-88% inhibition; drospirenone: 26-87% inhibition) in comparison to estrogens (estradiol: 17-51% inhibition; ethinylestradiol: 14-79% inhibition) and androgens (14-78% inhibition). Moreover, in most cases the synthetic hormones showed a greater ability to inhibit NNK reduction than the physiologic derivatives. These results demonstrate that male and female sex hormones have different inhibitory potentials, thus indicating that there is a varying detoxification capacity of NNK in men and women which could result in a different risk for developing lung cancer.


Assuntos
Aldo-Ceto Redutases/metabolismo , Hormônios Gonadais/metabolismo , Nitrosaminas/metabolismo , Redutases-Desidrogenases de Cadeia Curta/metabolismo , Aldo-Ceto Redutases/antagonistas & inibidores , Aldo-Ceto Redutases/genética , Androstenos/química , Androstenos/metabolismo , Carcinógenos/química , Carcinógenos/metabolismo , Estradiol/química , Estradiol/metabolismo , Hormônios Gonadais/química , Humanos , Inativação Metabólica , Fígado/enzimologia , Nitrosaminas/química , Progesterona/química , Progesterona/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Redutases-Desidrogenases de Cadeia Curta/antagonistas & inibidores , Redutases-Desidrogenases de Cadeia Curta/genética , Nicotiana/química , Nicotiana/metabolismo
16.
Ecotoxicol Environ Saf ; 139: 9-17, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28092737

RESUMO

In our previous study, we measured 0.23-13.67ng/L progestogens (progesterone, drospirenone, levonorgestrel) in natural waters in the catchment area of the largest shallow lake of Central Europe, Lake Balaton. Progestogen contaminations act as potent steroids with mixed progestagenic, androgenic and mild estrogenic effects that is why our aim was to investigate the morphological and molecular effects of mixture of progesterone, drospirenone, and levonorgestrel in environmentally relevant (10ng/L) and higher (50 and 500ng/L) exposure concentrations in common roach, Rutilus rutilus. Steroids (e.g. progestogens) and the protein deglycase DJ-1 chaperon molecule aim the same target molecules in cells, therefore, we hypothesized that a relationship may exist between progestogens and DJ-1. Furthermore, our other aim was to follow the changes of signal molecules of different biological function due to progestogen treatment in serum and brain. Adult roaches were exposed to 10, 50 and 500ng/L of mixture of progestogen for 42 days and their somatic indices (brain-somatic, liver-somatic, gonadosomatic and kidney-somatic) were measured. Vitellogenin (VTG) expression (estrogen effect) or inhibition (androgen effect) in fish is a widely used biomarker so we measured its changes in liver by ELISA. To determine the quantity and to map the spatial distribution of DJ-1 chaperon protein the brain and liver tissues were analyzed by ELISA and immunohistochemistry. Furthermore, we also studied molecular alterations: a) in the serum by measuring cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglyceride concentrations and b) in brain homogenate using a cell stress array kit (26 protein). The somatic index of liver and kidney significantly in all the treated groups, whereas the gonadosomatic index of 500ng/L treated group showed significant decrease compared to control animals. VTG level increased significantly in 500ng/L progestogen treated group. Since the concentration of DJ-1 significantly increased in brain and liver in all progestogen treatment groups, the DJ-1 protein could be able to a more sensitive marker than VTG. Serum LDL and cholesterol levels of exposed fish were significantly decreased. DJ-1 was mediated through the stimulation of the expression of LDL-receptor which facilitates reuptake subsequently. In summary, our observations unfolded new data about molecular alterations induced by the combined action of environmental progestogens. In addition, the DJ-1 chaperon protein as a possible biomarker helped to trace the abiotic chemical environmental contaminations, like progestogens in the freshwater ecosystems.


Assuntos
Androstenos/farmacologia , Cyprinidae/metabolismo , Levanogestrel/farmacologia , Progesterona/farmacologia , Progestinas/farmacologia , Proteína Desglicase DJ-1/metabolismo , Poluentes Químicos da Água/farmacologia , Androstenos/metabolismo , Animais , Biomarcadores/sangue , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Ecossistema , Exposição Ambiental/análise , Europa (Continente) , Feminino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Lagos/química , Levanogestrel/metabolismo , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Progesterona/metabolismo , Progestinas/metabolismo , Receptores de LDL/sangue , Vitelogeninas/metabolismo , Poluentes Químicos da Água/metabolismo
17.
J Clin Endocrinol Metab ; 102(3): 840-848, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27901631

RESUMO

Context: Androgen excess is a defining feature of polycystic ovary syndrome (PCOS), but the exact origin of hyperandrogenemia remains a matter of debate. Recent studies have highlighted the importance of the 11-oxygenated C19 steroid pathway to androgen metabolism in humans. In this study, we analyzed the contribution of 11-oxygenated androgens to androgen excess in women with PCOS. Methods: One hundred fourteen women with PCOS and 49 healthy control subjects underwent measurement of serum androgens by liquid chromatography-tandem mass spectrometry. Twenty-four-hour urinary androgen excretion was analyzed by gas chromatography-mass spectrometry. Fasting plasma insulin and glucose were measured for homeostatic model assessment of insulin resistance. Baseline demographic data, including body mass index, were recorded. Results: As expected, serum concentrations of the classic androgens testosterone (P < 0.001), androstenedione (P < 0.001), and dehydroepiandrosterone (P < 0.01) were significantly increased in PCOS. Mirroring this, serum 11-oxygenated androgens 11ß-hydroxyandrostenedione, 11-ketoandrostenedione, 11ß-hydroxytestosterone, and 11-ketotestosterone were significantly higher in PCOS than in control subjects, as was the urinary 11-oxygenated androgen metabolite 11ß-hydroxyandrosterone. The proportionate contribution of 11-oxygenated to total serum androgens was significantly higher in patients with PCOS compared with control subjects [53.0% (interquartile range, 48.7 to 60.3) vs 44.0% (interquartile range, 32.9 to 54.9); P < 0.0001]. Obese (n = 51) and nonobese (n = 63) patients with PCOS had significantly increased 11-oxygenated androgens. Serum 11ß-hydroxyandrostenedione and 11-ketoandrostenedione correlated significantly with markers of insulin resistance. Conclusions: We show that 11-oxygenated androgens represent the majority of circulating androgens in women with PCOS, with close correlation to markers of metabolic risk.


Assuntos
Androgênios/metabolismo , Glicemia/metabolismo , Hiperandrogenismo/metabolismo , Insulina/metabolismo , Obesidade/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adulto , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Androstenos/metabolismo , Estudos de Casos e Controles , Cromatografia Líquida , Desidroepiandrosterona/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidroxitestosteronas/metabolismo , Hiperandrogenismo/complicações , Resistência à Insulina , Obesidade/complicações , Síndrome do Ovário Policístico/complicações , Espectrometria de Massas em Tandem , Testosterona/análogos & derivados , Testosterona/metabolismo , Adulto Jovem
18.
Animal ; 11(6): 1071-1077, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27832828

RESUMO

Androstenone production increases during pubertal development and plays a major role in boar taint. The objective of the present study was to evaluate the effect of a subclinical inflammation on the pubertal development of boars and hence on fat androstenone. Contrasted hygiene conditions were applied during rearing to increase the variability of the inflammatory status. Boars from a commercial cross line were allocated at 139±0.9 days of age (Day 0) and 81.3±5.9 kg of live weight either to Good (n=61) or Poor (n=54) hygiene conditions until slaughter at 172.9±4.8 days of age and 116.7±4.5 kg live weight. Inflammatory status, growth and pubertal development were evaluated on Day 0, Day 27 and at slaughter by analysing the blood formula, plasma inflammatory proteins; testosterone and oestradiol, salivary cortisol, rectal temperature, live weight, back fat thickness, weight of reproductive organs and clinical scores of organs (lungs, stomach, snout). Fat was collected on Day 27 by biopsy and at slaughter to measure androstenone concentration. A principal component analysis including inflammatory indicators followed by a clustering procedure was performed to identify pigs with a high (Infl+, n=50) or a low (Infl-, n=65) inflammatory status. Infl+ pigs had more granulocytes/ml, higher concentrations of haptoglobin, C-reative protein and cortisol (P<0.05), lower growth rate and higher lung pneumonia score. However, regardless of stage, the inflammatory status had no significant effect on plasma testosterone or oestradiol, fat androstenone or sexual organ development. Present data suggest that a mild inflammatory status has no influence on pubertal development or fat concentration of androstenone in boars.


Assuntos
Androstenos/metabolismo , Maturidade Sexual , Suínos/fisiologia , Tecido Adiposo/metabolismo , Animais , Estradiol/sangue , Inflamação , Masculino , Reprodução , Esteroides/sangue , Suínos/crescimento & desenvolvimento , Suínos/imunologia , Testosterona/sangue
20.
Nature ; 533(7604): 547-51, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27225130

RESUMO

Abiraterone blocks androgen synthesis and prolongs survival in patients with castration-resistant prostate cancer, which is otherwise driven by intratumoral androgen synthesis. Abiraterone is metabolized in patients to Δ(4)-abiraterone (D4A), which has even greater anti-tumour activity and is structurally similar to endogenous steroidal 5α-reductase substrates, such as testosterone. Here, we show that D4A is converted to at least three 5α-reduced and three 5ß-reduced metabolites in human serum. The initial 5α-reduced metabolite, 3-keto-5α-abiraterone, is present at higher concentrations than D4A in patients with prostate cancer taking abiraterone, and is an androgen receptor agonist, which promotes prostate cancer progression. In a clinical trial of abiraterone alone, followed by abiraterone plus dutasteride (a 5α-reductase inhibitor), 3-keto-5α-abiraterone and downstream metabolites were depleted by the addition of dutasteride, while D4A concentrations rose, showing that dutasteride effectively blocks production of a tumour-promoting metabolite and permits D4A accumulation. Furthermore, dutasteride did not deplete the three 5ß-reduced metabolites, which were also clinically detectable, demonstrating the specific biochemical effects of pharmacological 5α-reductase inhibition on abiraterone metabolism. Our findings suggest a previously unappreciated and biochemically specific method of clinically fine-tuning abiraterone metabolism to optimize therapy.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Androgênios/biossíntese , Androstenos/metabolismo , Dutasterida/farmacologia , Dutasterida/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Inibidores de 5-alfa Redutase/uso terapêutico , Acetato de Abiraterona/administração & dosagem , Acetato de Abiraterona/sangue , Acetato de Abiraterona/metabolismo , Acetato de Abiraterona/uso terapêutico , Administração Oral , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Androstenos/administração & dosagem , Androstenos/sangue , Androstenos/farmacologia , Animais , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Masculino , Camundongos , Oxirredução/efeitos dos fármacos , Neoplasias da Próstata/sangue , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
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