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1.
Angew Chem Int Ed Engl ; 60(10): 5414-5420, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33258169

RESUMEN

4-Androstenedione (4-AD) and progesterone (PG) are two of the most important precursors for synthesis of steroid drugs, however their current manufacturing processes suffer from low efficiency and severe environmental issues. In this study, we decipher a dual-role reductase (mnOpccR) in the phytosterols catabolism, which engages in two different metabolic branches to produce the key intermediate 20-hydroxymethyl pregn-4-ene-3-one (4-HBC) through a 4-e reduction of 3-oxo-4-pregnene-20-carboxyl-CoA (3-OPC-CoA) and 2-e reduction of 3-oxo-4-pregnene-20-carboxyl aldehyde (3-OPA), respectively. Inactivation or overexpression of mnOpccR in the Mycobacterium neoaurum can achieve exclusive production of either 4-AD or 4-HBC from phytosterols. By utilizing a two-step synthesis, 4-HBC can be efficiently converted into PG in a scalable manner (100 gram scale). This study deciphers a pivotal biosynthetic mechanism of phytosterol catabolism and provides very efficient production routes of 4-AD and PG.


Asunto(s)
Proteínas Bacterianas/metabolismo , Oxidorreductasas/metabolismo , Fitosteroles/metabolismo , Pregnenos/metabolismo , Androstenodiona/síntesis química , Proteínas Bacterianas/genética , Biocatálisis , Mycobacteriaceae/enzimología , Mycobacteriaceae/genética , Oxidorreductasas/genética , Pregnenos/química , Progesterona/síntesis química
2.
Chem Commun (Camb) ; 55(57): 8231-8234, 2019 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-31241075

RESUMEN

Withangulatin A (WA) has been reported to exhibit potent antitumor activity. However, its possible mechanism and direct proteomic targets remain unknown. Herein we report the subcellular localization of WA by designing and synthesizing its fluorescent analogues with coumarin moieties. Furthermore, sarco/endoplasmic reticulum calcium-ATPase (SERCA)2 was identified as the potential target of WA for its antitumor activity by chemical proteomics.


Asunto(s)
Colorantes Fluorescentes/química , Pregnenos/análisis , Proteómica/métodos , Línea Celular Tumoral , Cumarinas/química , Humanos , Microscopía Fluorescente , Pregnenos/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/análisis , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo
3.
Reproduction ; 157(5): 413-422, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30763279

RESUMEN

Dexamethasone (DEX) initiates parturition by inducing progesterone withdrawal and affecting placental steroidogenesis, but the effects of DEX in fetal and maternal tissue steroid synthetic capacity remains poorly investigated. Blood was collected from cows at 270 days of gestation before DEX or saline (SAL) treatment, and blood and tissues were collected at slaughter 38 h later. Steroid concentrations were determined by liquid chromatography tandem mass spectrometry to detect multiple steroids including 5α-reduced pregnane metabolites of progesterone. The activities of 3ß-hydroxysteroid dehydrogenase (3ßHSD) in cotyledonary and luteal microsomes and mitochondria and cotyledonary microsomal 5α-reductase were assessed. Quantitative PCR was used to further assess transcripts encoding enzymes and factors supporting steroidogenesis in cotyledonary and luteal tissues. Serum progesterone, pregnenolone, 5α-dihydroprogesterone (DHP) and allopregnanolone (3αDHP) concentrations (all <5 ng/mL before treatment) decreased in cows after DEX. However, the 20α-hydroxylated metabolite of DHP, 20αDHP, was higher before treatment (≈100 ng/mL) than at slaughter but not affected by DEX. Serum, cotyledonary and luteal progesterone was lower in DEX- than SAL-treated cows. Progesterone was >100-fold higher in luteal than cotyledonary tissues, and serum and luteal concentrations were highly correlated in DEX-treated cows. 3ßHSD activity was >5-fold higher in luteal than cotyledonary tissue, microsomes had more 3ßHSD than mitochondria in luteal tissue but equal in cotyledonary sub-cellular fractions. DEX did not affect either luteal or cotyledonary 3ßHSD activity but luteal steroidogenic enzyme transcripts were lower in DEX-treated cows. DEX induced functional luteal regression and progesterone withdrawal before any changes in placental pregnene/pregnane synthesis and/or metabolism were detectable.


Asunto(s)
Bovinos , Dexametasona/farmacología , Parto/efectos de los fármacos , Preñez , Pregnanos/metabolismo , Pregnenos/metabolismo , Animales , Bovinos/metabolismo , Cuerpo Lúteo/efectos de los fármacos , Cuerpo Lúteo/metabolismo , Femenino , Feto/efectos de los fármacos , Feto/metabolismo , Edad Gestacional , Luteólisis/sangre , Luteólisis/efectos de los fármacos , Luteólisis/metabolismo , Parto/metabolismo , Embarazo , Preñez/sangre , Preñez/efectos de los fármacos , Preñez/metabolismo , Pregnanos/sangre , Pregnenos/sangre , Progesterona/metabolismo
4.
Microb Cell Fact ; 17(1): 100, 2018 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-29940969

RESUMEN

BACKGROUND: Metabolic activities of microorganisms to modify the chemical structures of organic compounds became an effective tool for the production of high-valued steroidal drugs or their precursors. Currently research efforts in production of steroids of pharmaceutical interest are focused on either optimization of existing processes or identification of novel potentially useful bioconversions. Previous studies demonstrated that P. lanosocoeruleum KCH 3012 metabolizes androstanes to the corresponding lactones with high yield. In order to explore more thoroughly the factors determining steroid metabolism by this organism, the current study was initiated to delineate the specificity of this fungus with respect to the cleavage of steroid side chain of progesterone and pregnenolone The effect of substituents at C-16 in 16-dehydropregnenolone, 16α,17α-epoxy-pregnenolone and 16α-methoxy-pregnenolone on the pattern of metabolic processing of these steroids was also investigated. RESULTS AND DISCUSSION: All of the analogues tested (except the last of the listed) in multi-step transformations underwent the Baeyer-Villiger oxidation to their δ-D-lactones. The activity of 3ß-HSD was a factor affecting the composition of the product mixtures. 16α,17α-epoxy-pregnenolone underwent a rare epoxide opening with retention stereochemistry to give four 16α-hydroxy-lactones. Apart from oxidative transformations, a reductive pathway was revealed with the unique hydrogenation of 5-ene double bond leading to the formation of 3ß,16α-dihydroxy-17a-oxa-D-homo-5α-androstan-17-one. 16α-Methoxy-pregnenolone was transformed to the 20(R)-alcohol with no further conversion. CONCLUSIONS: This work clearly demonstrated that P. lanosocoeruleum KCH 3012 has great multi-functional catalytic properties towards the pregnane-type steroids. Studies have highlighted that a slight modification of the D-ring of substrates may control metabolic fate either into the lactonization or reductive and oxidative pathways. Possibility of epoxide opening by enzymes from this microorganism affords a unique opportunity for generation of novel bioactive steroids.


Asunto(s)
Lactonas/metabolismo , Redes y Vías Metabólicas , Penicillium/metabolismo , Pregnenos/metabolismo , Esteroides/metabolismo , Biotransformación , Catálisis , Compuestos Epoxi/metabolismo , Estructura Molecular , Oxidación-Reducción , Pregnenolona/análogos & derivados , Pregnenolona/metabolismo , Progesterona/metabolismo
5.
J Bacteriol ; 200(2)2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29109182

RESUMEN

The heteromeric acyl coenzyme A (acyl-CoA) dehydrogenase FadE28-FadE29 and the enoyl-CoA hydratase ChsH1-ChsH2, encoded by genes within the intracellular growth (igr) operon of Mycobacterium tuberculosis, catalyze the dehydrogenation of the cholesterol metabolite 3-oxo-4-pregnene-20-carboxyl-CoA (3-OPC-CoA), with a 3-carbon side chain, and subsequent hydration of the product 3-oxo-4,17-pregnadiene-20-carboxyl-CoA (3-OPDC-CoA) to form 17-hydroxy-3-oxo-4-pregnene-20-carboxyl-CoA (17-HOPC-CoA). The gene downstream of chsH2, i.e., ltp2, was expressed in recombinant Rhodococcus jostii RHA1 in combination with other genes within the igr operon. His-tagged Ltp2 copurified with untagged ChsH1-ChsH2, ChsH2, or the C-terminal domain of ChsH2, which contains a domain of unknown function (DUF35). Ltp2 in association with ChsH1-ChsH2 or just the DUF35 domain of ChsH2 was shown to catalyze the retroaldol cleavage of 17-HOPC-CoA to form androst-4-ene-3,17-dione and propionyl-CoA. Steady-state kinetic analysis using the Ltp2-DUF35 complex showed that the aldolase had optimal activity at pH 7.5, with a Km of 6.54 ± 0.90 µM and a kcat of 159 ± 8.50 s-1 ChsH1-ChsH2 could hydrate only about 30% of 3-OPDC-CoA, but this unfavorable equilibrium could be overcome when the aldolase was present to remove the hydrated product, providing a rationale for the close association of the aldolase with the hydratase. Homologs of ChsH1, ChsH2, and Ltp2 are found in steroid-degrading Gram-positive and Gram-negative bacteria, suggesting that side chains of diverse steroids may be cleaved by aldolases in the bacteria.IMPORTANCE The C-C bond cleavage of the D-ring side chain of cholesterol was shown to be catalyzed by an aldolase. The aldolase associates with the hydratase that catalyzes the preceding reaction in the cholesterol side chain degradation pathway. These enzymes are encoded by genes within the intracellular growth (igr) operon of M. tuberculosis, and the operon was demonstrated previously to be linked to the pathogenicity and persistence of the bacteria in macrophages and in mice.


Asunto(s)
Colesterol/metabolismo , Fructosa-Bifosfato Aldolasa/genética , Fructosa-Bifosfato Aldolasa/metabolismo , Mycobacterium tuberculosis/enzimología , Acilcoenzima A/genética , Acilcoenzima A/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biocatálisis , Colesterol/química , Enoil-CoA Hidratasa/genética , Enoil-CoA Hidratasa/metabolismo , Fructosa-Bifosfato Aldolasa/biosíntesis , Concentración de Iones de Hidrógeno , Cinética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Operón , Pregnenos/química , Pregnenos/metabolismo , Proteínas Recombinantes/metabolismo , Rhodococcus/genética
6.
J Am Soc Mass Spectrom ; 25(5): 869-79, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24658800

RESUMEN

Steroid conjugates, which often occur as metabolites, are challenging to characterize. One application is female-mouse urine, where steroid conjugates serve as important ligands for the pheromone-sensing neurons. Although the two with the highest abundance in mouse urine were previously characterized with mass spectrometry (MS) and NMR to be sulfated steroids, many more exist but remain structurally unresolved. Given that their physical and chemical properties are similar, they are likely to have a sulfated steroid ring structure. Because these compounds occur in trace amounts in mouse urine and elsewhere, their characterization by NMR will be difficult. Thus, MS methods become the primary approach for determining structure. Here, we show that a combination of MS tools is effective for determining the structures of sulfated steroids. Using 4-pregnene analogs, we explored high-resolving power MS (HR-MS) to determine chemical formulae; HD exchange MS (HDX-MS) to determine number of active, exchangeable hydrogens (e.g., OH groups); methoxyamine hydrochloride (MOX) derivatization MS, or reactive desorption electrospray ionization with hydroxylamine to determine the number of carbonyl groups; and tandem MS (MS(n)), high-resolution tandem MS (HRMS/MS), and GC-MS to obtain structural details of the steroid ring. From the fragmentation studies, we deduced three major fragmentation rules for this class of sulfated steroids. We also show that a combined MS approach is effective for determining structure of steroid metabolites, with important implications for targeted metabolomics in general and for the study of mouse social communication in particular.


Asunto(s)
Hidrocortisona/análogos & derivados , Pregnenos/metabolismo , Métodos Analíticos de la Preparación de la Muestra , Animales , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hidrocortisona/química , Hidrocortisona/metabolismo , Hidroxilaminas/química , Indicadores y Reactivos/química , Ratones , Estructura Molecular , Peso Molecular , Pregnenos/química , Pregnenos/orina , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
7.
Steroids ; 78(14): 1312-24, 2013 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-24135562

RESUMEN

Structural modification of steroids through whole-cell biocatalysis is an invaluable procedure for the production of active pharmaceutical ingredients (APIs) and key intermediates. Modifications could be carried out with regio- and stereospecificity at positions hardly available for chemical agents. Much attention has been focused recently on the biotransformation of 17α-ethynyl substituted steroidal drugs using fungi, bacteria and plant cell cultures in order to obtained novel biologically active compounds with diverse structure features. Present article includes studies on biotransformation on 17α-ethynyl substituted steroidal drugs using microorganisms and plant cell cultures. Various experimental and structural elucidation methods used in biotransformational processes are also highlighted.


Asunto(s)
Estrenos/metabolismo , Etinilestradiol/metabolismo , Norpregnenos/metabolismo , Pregnenos/metabolismo , Bacterias/metabolismo , Biotransformación , Técnicas de Cultivo de Célula , Descubrimiento de Drogas , Estrenos/química , Estrenos/aislamiento & purificación , Etinilestradiol/química , Etinilestradiol/aislamiento & purificación , Hongos/metabolismo , Humanos , Norpregnenos/química , Norpregnenos/aislamiento & purificación , Células Vegetales/metabolismo , Pregnenos/química , Pregnenos/aislamiento & purificación , Estereoisomerismo
8.
Steroids ; 77(5): 382-93, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22210448

RESUMEN

Urine from neonates with 21-hydroxylase deficiency contains a large range of metabolites of 17-hydroxyprogesterone, 21-deoxycortisol and androgens but few have been previously described. We present the second part of a comprehensive project to characterize and identify these in order to enhance diagnosis and to further elucidate neonatal steroid metabolism. Steroids were analyzed, after extraction and enzymatic conjugate hydrolysis, as methyloxime-trimethylsilyl ether derivatives on gas-chromatographs coupled to quadrupole and ion-trap mass-spectrometers. GC-MS and GC-MS/MS spectra were used together to determine the structure of the A- and B-rings containing an oxo group. Fragmentations indicating presence of 3-, 6-, and 7-oxo groups and also 1ß-, 2α-, 4ß-, and 6ß-hydroxyls are presented and discussed for the first time. Interpretation was aided by comparison with spectra of available relevant standards, of oxidation products of standards and urinary metabolites and of deuterated derivatives. Endogenous 1-enes and 2(3)-ene artifacts of non-hydrolyzed 3α-sulfates are also reported. D-ring and side chain structure was determined according to our previously published criteria. Likely metabolic relationships were also explored. We conclude that GC-MS combined with GC-MS/MS allows identification of the A- and B-ring structure of pregnane and pregnenes in the presence of an oxo group on one of these rings. Major oxygenations are 1ß, 15ß, 16α and 21-hydroxy and 6- and 7-oxo groups. Minor positions of hydroxylation are those at 2α, 4ß and 6ß. Three major metabolic streams exist in affected neonates in addition to the classical 3α-hydroxy-5ß-pregnane pathway, i.e. these of the 3-oxo-4-enes as well as 3α- and 3ß-hydroxy-5α-anes.


Asunto(s)
Hiperplasia Suprarrenal Congénita/orina , Esteroides/química , Esteroides/orina , Hiperplasia Suprarrenal Congénita/enzimología , Cromatografía de Gases , Cromatografía de Gases y Espectrometría de Masas , Humanos , Recién Nacido , Espectrometría de Masas , Redes y Vías Metabólicas , Estructura Molecular , Oxidación-Reducción , Pregnanos/química , Pregnanos/metabolismo , Pregnanos/orina , Pregnenos/química , Pregnenos/metabolismo , Pregnenos/orina , Esteroide 21-Hidroxilasa/metabolismo , Esteroides/metabolismo
9.
Steroids ; 75(1): 34-52, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19799922

RESUMEN

Steroid metabolites in urine from neonates with 21-hydroxylase deficiency are predominantly polyhydroxylated 17-hydroxyprogesterone and androgen metabolites, and most have incompletely defined structure. This study forms part of a comprehensive project to characterize and identify these in order to enhance diagnosis and to further elucidate neonatal types of steroid metabolism. Steroids were analyzed, after extraction and enzymatic conjugate hydrolysis, as methyloxime-trimethylsilyl ether derivatives on gas-chromatographs coupled to quadrupole and ion-trap mass-spectrometers. GC-MS and GC-MS/MS spectra, obtained with constant excitation conditions, were used together to determine the structure of the D-ring and the side chain of 20-oxo and 20-hydroxy pregnane(ene)s without oxo groups on the A-, B-, and C-ring. All possible combinations of D-ring and side chain configuration were considered. Most fragmentations could be interpreted as partial or complete D-ring cleavages with loss of the side chain, aided by comparison with spectra of deuterated derivatives and of borohydride reduced metabolites. Possible rearrangement ions are also discussed. More than 140 endogenous metabolites were characterized. GC-MS/MS was especially beneficial for characterization of compounds with 16,17-dihydroxy-20-oxo structure, interpreted as markers of intra-uterine enzyme induction. It also assisted the differentiation of 16-hydroxy-20-oxo metabolites, present in urine of non-affected neonates, from the diagnostic 17-hydroxy-20-oxosteroids and enabled the detection of 15,17-dihydroxy-20-oxo compounds in low concentrations. The presence of 17,21-dihydroxylated pregnane(ene)s despite the deficit in CYP21A2 is discussed. We conclude that GC-MS combined with GC-MS/MS allows reliable identification of the structure of the D-ring and side chain of pregnane(ene)s without prior isolation, even when in low concentrations in urine.


Asunto(s)
Cromatografía de Gases/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Esteroide 21-Hidroxilasa/metabolismo , Esteroides/orina , 17-alfa-Hidroxiprogesterona/química , 17-alfa-Hidroxiprogesterona/metabolismo , Hiperplasia Suprarrenal Congénita/enzimología , Hiperplasia Suprarrenal Congénita/genética , Humanos , Hidroxilación , Hidroxiprogesteronas/química , Hidroxiprogesteronas/metabolismo , Lactante , Recién Nacido , Pregnanos/química , Pregnanos/metabolismo , Pregnanos/orina , Pregnenos/química , Pregnenos/metabolismo , Pregnenos/orina , Esteroide 21-Hidroxilasa/genética , Esteroides/química , Esteroides/metabolismo
10.
Physiol Behav ; 99(1): 8-16, 2010 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-19833145

RESUMEN

With salivary assessment of steroid hormones increasing, more work is needed to address fundamental properties of steroid hormone levels in humans. Using a test-retest design and radioimmunoassay assessment of salivary steroids, we tested the reliability of testosterone, cortisol, and progesterone levels across two weeks, as well as the effects of oral contraceptives, menstrual cycle phase, and time of day on steroid hormone levels. Testosterone and cortisol were found to be highly reliable in both sexes. Progesterone was found to be reliable after collapsing across sex. Oral contraceptive use was associated with lower levels of testosterone, but did not affect cortisol. Contrary to expectations, oral contraceptives also did not affect progesterone. Menstrual cycle was found to affect levels of progesterone, but not testosterone or cortisol. Time of day had an effect on cortisol, on progesterone only at one testing time, and no effect on testosterone. We explored the interhormone correlations among testosterone, progesterone, and cortisol. All three hormones were positively correlated with one another in men. In women, progesterone was positively correlated with testosterone and cortisol, but testosterone and cortisol were uncorrelated.


Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Anticonceptivos Hormonales Orales/farmacología , Hidrocortisona/metabolismo , Ciclo Menstrual/efectos de los fármacos , Pregnenos/metabolismo , Saliva/efectos de los fármacos , Testosterona/metabolismo , Adolescente , Análisis de Varianza , Ritmo Circadiano/fisiología , Femenino , Humanos , Radioinmunoensayo/métodos , Reproducibilidad de los Resultados , Saliva/metabolismo , Caracteres Sexuales , Factores de Tiempo , Adulto Joven
11.
Endocr Relat Cancer ; 13(3): 717-38, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16954427

RESUMEN

In the 70 years since progesterone (P) was identified in corpus luteum extracts, its metabolism has been examined extensively in many tissues and cell lines from numerous species. In addition to the reproductive tissues and adrenals, every other tissue that has been investigated appears to have one or more P-metabolizing enzyme, each of which is specific for a particular site on the P molecule. In the past, the actions of the P metabolizing enzymes generally have been equated to a means of reducing the P concentration in the tissue microenvironment, and the products have been dismissed as inactive waste metabolites. In human breast tissues and cell lines, the following P-metabolizing enzymes have been identified: 5alpha-reductase, 3alpha-hydroxysteroid oxidoreductase (3alpha-HSO), 3beta-HSO, 20alpha-HSO, and 6alpha-hydroxylase. Rather than providing diverse pathways for inactivating and controlling the concentration of P in breast tissue microenvironments, it is proposed that the enzymes act directly on P to produce two types of autocrines/paracrines with opposing regulatory roles in breast cancer. Evidence is reviewed which shows that P is directly converted to the 4-pregnenes, 3alpha-hydroxy-4-pregnen-20-one (3alpha-dihydroprogesterone; 3alphaHP) and 20alpha-dihydroprogesterone (20alphaHP), by the actions of 3alpha-HSO and 20alpha-HSO respectively and to the 5alpha-pregnane, 5alpha-pregnane-3,20-dione(5alpha-dihydroprogesterone; 5alphaP), by the irreversible action of 5alpha-reductase. In vitro studies on a number of breast cell lines indicate that 3alphaHP promotes normalcy by downregulating cell proliferation and detachment, whereas 5alphaP promotes mitogenesis and metastasis by stimulating cell proliferation and detachment. The hormones bind to novel, separate, and specific plasma membrane-based receptors and influence opposing actions on mitosis, apoptosis, and cytoskeletal and adhesion plaque molecules via cell signaling pathways. In normal tissue, the ratio of 4-pregnenes:5alpha-pregnanes is high because of high P 3alpha- and 20alpha-HSO activities/expression and low P 5alpha-reductase activity/expression. In breast tumor tissue and tumorigenic cell lines, the ratio is reversed in favor of the 5alpha-pregnanes because of altered P-metabolizing enzyme activities/expression. The evidence suggests that the promotion of breast cancer is related to changes in in situ concentrations of cancer-inhibiting and -promoting P metabolites. Current estrogen-based theories and therapies apply to only a fraction of all breast cancers; the majority (about two-thirds) of breast cancer cases are estrogen-insensitive and have lacked endocrine explanations. As the P metabolites, 5alphaP and 3alphaHP, have been shown to act with equal efficacy on all breast cell lines tested, regardless of their tumorigenicity, estrogen sensitivity, and estrogen receptor/progesterone receptor status, it is proposed that they offer a new hormonal basis for all forms of breast cancer. New diagnostic and therapeutic possibilities for breast cancer progression, control, regression, and prevention are suggested.


Asunto(s)
Neoplasias de la Mama/metabolismo , Progesterona/metabolismo , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , División Celular , Línea Celular Tumoral , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Mitosis , Pregnenos/metabolismo , Receptores de Progesterona/metabolismo
12.
Eksp Klin Farmakol ; 69(4): 36-8, 2006.
Artículo en Ruso | MEDLINE | ID: mdl-16995436

RESUMEN

Chemical modification of progesterone molecule leads to changes both in the gestagenic activity of new derivatives and in their specific binding with progesterone receptors. The passage from esters (acetomepregenole, butagest) to the corresponding OH-forms such as 17a-acetoxy-3b-hydroxy-6-methyl-pregna-4,6-dien-20-one (ABMP)is accompanied by an increase in the binding with progesterone receptors in vitro. The translocation of a double bond from endocyclic (N6-N7) to exocyclic position (methylene group at N6 in ABMP) has no significant effect on the ability to binding with progesterone receptors.


Asunto(s)
Endometrio/metabolismo , Congéneres de la Progesterona/metabolismo , Progestinas/metabolismo , Receptores de Progesterona/metabolismo , 17-alfa-Hidroxiprogesterona/análogos & derivados , 17-alfa-Hidroxiprogesterona/química , 17-alfa-Hidroxiprogesterona/metabolismo , Adulto , Hiperplasia Endometrial/metabolismo , Hiperplasia Endometrial/prevención & control , Femenino , Humanos , Hidroxiprogesteronas/química , Hidroxiprogesteronas/metabolismo , Persona de Mediana Edad , Pregnadienodioles/química , Pregnadienodioles/metabolismo , Pregnenos/química , Pregnenos/metabolismo , Congéneres de la Progesterona/química , Progestinas/química , Relación Estructura-Actividad
13.
J Steroid Biochem Mol Biol ; 100(4-5): 129-40, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16806904

RESUMEN

Recent evidence indicates that progesterone metabolites play important roles in regulating breast cancer. Previous studies have shown that breast carcinoma and tumorigenic breast cell lines have higher 5alpha-reductase and lower 3alpha-hydroxysteroid oxidoreductase (3alpha-HSO) and 20alpha-HSO activities and mRNA expression levels than normal tissue and non-tumorigenic cell lines. The 5alpha-reduced progesterone metabolites such as 5alpha-dihydroprogesterone (5alphaP) promote both mitogenic and metastatic activity in breast cell lines in culture, whereas the 4-pregnene metabolites, 4-pregnen-3alpha-ol-20-one (3alphaHP) and 4-pregnen-20alpha-ol-3-one (20alphaHP) have the opposite (anti-cancer-like) effects. The 5alpha-reductase inhibitor dutasteride has been shown to inhibit 5alpha-reduction of testosterone to 5alpha-dihydrotestosterone in prostate tissue, resulting in decreased prostate volume. The aim of this study was to determine if dutasteride is an effective inhibitor of progesterone 5alpha-reduction in human breast cell lines and if such inhibition reduces mammary cell proliferation and detachment. The effect of dutasteride on progesterone metabolizing enzyme activities and mRNA expression were examined in tumorigenic MCF-7 and non-tumorigenic MCF-10A human breast cell lines. Dutasteride (10(-6)M) inhibited progesterone conversion to 5alpha-pregnanes by >95% and increased 4-pregnene production. The results indicated that effects of dutasteride on the progesterone metabolizing enzymes are due to direct inhibition of 5alpha-reductase activity and to altered levels of expression of 5alpha-reductase and HSO mRNAs. Treatment of cells with progesterone without medium change for 72 h resulted in significant conversion to 5alpha-pregnanes and increases in cell proliferation and detachment. The increases in proliferation and detachment were blocked by dutasteride and were reinstated by concomitant treatment with 5alphaP, providing proof-of-principle that the effects were due not to progesterone but to the 5alpha-reduced metabolites. This study provides the first evidence that dutasteride is a potent progesterone 5alpha-reductase inhibitor and that such inhibition may be beneficial in breast cancer.


Asunto(s)
3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , Azaesteroides/metabolismo , Mama/citología , Adhesión Celular/fisiología , Proliferación Celular , Inhibidores Enzimáticos/metabolismo , Progesterona/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/genética , Inhibidores de 5-alfa-Reductasa , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular , Dutasterida , Femenino , Humanos , Estructura Molecular , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Pregnanos/química , Pregnanos/metabolismo , Pregnenos/metabolismo , ARN Mensajero/metabolismo
15.
J Steroid Biochem Mol Biol ; 93(2-5): 201-8, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15860263

RESUMEN

Proliferative changes in the normal breast are known to be controlled by female sex steroids. However, only a portion of all breast cancer patients respond to current estrogen based endocrine therapy, and with continued treatment nearly all will become unresponsive and experience relapse. Therefore, ultimately for the majority of breast carcinomas, explanations and treatments based on estrogen are inadequate. Recent observations indicate that 5alpha-pregnane and 4-pregnene progesterone metabolites may serve as regulators of estrogen-responsive as well as unresponsive human breast cancers. The conversion of progesterone to the 5alpha-pregnanes is increased while conversion to the 4-pregnenes is decreased in breast carcinoma tissue, as a result of changes in progesterone metabolizing 5alpha-reductase, 3alpha-hydroxysteroid oxidoreductase (3alpha-HSO) and 20alpha-HSO activities and gene expression. The 5alpha-pregnane, 5alpha-pregnane-3,20-dione (5alphaP) stimulates, whereas the 4-pregnene, 3alpha-hydroxy-4-pregnen-20-one (3alphaHP), inhibits cell proliferation and detachment, by modulation of cytoskeletal and adhesion plaque molecules via the MAP kinase pathway and involving separate and specific plasma membrane-based receptors. The promotion of breast cancer appears to be related to changes in in situ concentrations of cancer-inhibiting and cancer-promoting progesterone metabolites. New diagnostic and therapeutic possibilities for breast cancer are suggested.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias Hormono-Dependientes/metabolismo , Progesterona/metabolismo , 20-alfa-Hidroxiesteroide Deshidrogenasa/genética , 20-alfa-Hidroxiesteroide Deshidrogenasa/metabolismo , 3-alfa-Hidroxiesteroide Deshidrogenasa (B-Específica)/genética , 3-alfa-Hidroxiesteroide Deshidrogenasa (B-Específica)/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Mama/metabolismo , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Carcinógenos/metabolismo , Carcinógenos/toxicidad , Adhesión Celular/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Colestenona 5 alfa-Reductasa/genética , Colestenona 5 alfa-Reductasa/metabolismo , Femenino , Humanos , Sistema de Señalización de MAP Quinasas , Neoplasias Hormono-Dependientes/diagnóstico , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias Hormono-Dependientes/genética , Pregnanos/metabolismo , Pregnanos/toxicidad , Pregnenos/metabolismo , Pregnenos/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo
16.
Vertex ; 15(57): 183-95, 2004.
Artículo en Español | MEDLINE | ID: mdl-15505680

RESUMEN

That the brain is a target for hormones is a well established fact. Today we also know that brains can secrete the whole gamut of peptides and steroid hormones, i.e., pregnanes and pregnenes. Considering that the ancestral neuron was a neurosecreting cell, this is not surprising. As CRH and cortisol secretion occur in situ in nervous systems, the intriguing possibility that anxio-depressive syndromes may be associated with paracrine effects of these compounds on the brain should now be considered. The concept of stress as a specific reaction of the nueroendocrine system to nocuous stimuli is re-examined in light of new evidence. The fundamental importance of historical, social, and psychological contexts in evaluating hormonal actions is emphasized. Problems emerging from the attempt to search for specific biological markers in different psychiatric disorders are discussed. The suggestion is made that, rather than to categorize nosological entities, biological dysfunctions should be elated with psychological abnormalities.


Asunto(s)
Encéfalo/metabolismo , Depresión/metabolismo , Desoxicorticosterona/metabolismo , Pregnanos/metabolismo , Estrés Psicológico/metabolismo , Ansiedad/metabolismo , Depresión/genética , Femenino , Humanos , Pregnenos/metabolismo , Receptores de GABA/metabolismo
17.
Steroids ; 68(9): 707-17, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14625002

RESUMEN

This paper collates and reviews a number of clinical cases published over the last 20 years that we believe describe a novel steroid disorder associated with genital ambiguity. The authors of the original papers were unable to diagnose their patients conclusively. Females with the disorder are frequently masculinized and males feminized. The central feature of steroid biosynthesis is overproduction of pregnenolone and progesterone, which results in elevated concentrations of these steroids in plasma and exaggerated response to ACTH. Equivalent urinary data show elevated excretion of 5-pregnene-3beta,20alpha-diol (the major pregnenolone metabolite) and pregnanediol. Another notable feature of the metabolome is the relatively high plasma concentrations of the analytes for 21-hydroxylase deficiency (17-hydroxyprogesterone) and 17-hydroxylase deficiency (corticosterone). Correspondingly, metabolites of these steroids are prominent in urine. Circulating cortisol was generally normal but had blunted response to ACTH. Taken together these features pointed to an apparent relative deficiency of 21- and 17-hydroxylation, but no mutations have been found in the enzymes responsible for these transformations in cases where it has been investigated. The simultaneous presence of mutated genes on two chromosomes is also extremely unlikely. Until more is known of this interesting condition, and the genetic cause (presumed) is known, we propose naming it apparent pregnene hydroxylation deficiency (APHD). The metabolome is similar to that of isolated 17,20-lyase deficiency with which it has been confused. In fact, diminished (but not isolated) lyase activity is probably a significant factor in some patients. We believe that the attenuated steroid hydroxylation could be associated with deficiency of the required co-factors and modulators of hydroxylation such as P450 reductase and cytochrome b5. Post-translational modifications of the hydroxylases such as phosphorylation/dephosphorylation have also been suggested as influential in directionally regulating steroid synthesis. Some patients with the disorder have no dysmorphology apart from genital malformations while others have skeletal abnormalities attributed to Antley-Bixler syndrome. Whether we are looking at different conditions, or a severity continuum is not known. It is possible that the presence of this metabolome may become a required feature for diagnosis of Antley-Bixler syndrome. A combination of intersex phenotype and dysmorphology suggests that an error in a transcription factor may be an alternative to hydroxylation redox partner deficit as causative of the condition.The virilization of female patients with APHD probably results from a transient hyperandrogenism prior to birth.


Asunto(s)
Errores Congénitos del Metabolismo Esteroideo/metabolismo , Adolescente , Adulto , Niño , Preescolar , Femenino , Trastornos Gonadales/metabolismo , Humanos , Hidroxilación , Lactante , Masculino , Pregnenos/metabolismo , Pregnenolona/metabolismo , Progesterona/metabolismo , Errores Congénitos del Metabolismo Esteroideo/genética , Esteroides/metabolismo
18.
Biol Pharm Bull ; 26(9): 1321-5, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12951479

RESUMEN

Gagaminine, a steroidal alkaloid isolated from the roots of Cynanchum wilfordii, exhibited potent inhibitory effects on aldehyde oxidase activity and lipid peroxidation. To determine whether it would be possible to mass produce this active component, which would be useful for animal tests, we tried to synthesize it using in vitro cell culture methods with various growth conditions. In a previous study it was found that calli were easily induced from the stem of this medicinal plant and cultivated effectively on MS medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) 2 mg/l. In this work we attempted to determine the effects of various culture conditions on cell growth and gagaminine synthesis in suspension culture. Gagaminine production was increased markedly when cell growth proceeded to the death phase. Cell growth was more effective with 5% (v/v) sucrose, in the light (at 38 microE/m(2) x s), on medium containing 2,4-D 2 mg/l, with 2.5 g/10 ml medium as the initial cell concentration. The concentration of gagaminine was optimal with 3% sucrose, in darkness on medium 2,4-D 1 mg/l, with 2.5 g/10 ml medium as an initial cell concentration. However, the highest growth rate was 0.18 d(-1), when the gagaminine concentration was seven- and three-fold (at 140 mu/ml) that of the plant stem and 10 ml of medium respectively, on the 50 ml of medium in suspension culture.


Asunto(s)
Cinamatos/metabolismo , Cynanchum/metabolismo , Pregnenos/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacología , División Celular , Células Cultivadas , Cynanchum/citología , Cynanchum/efectos de los fármacos , Herbicidas/farmacología , Cinética , Luz , Raíces de Plantas/química , Sacarosa/farmacología , Temperatura
19.
J Med Chem ; 45(24): 5397-405, 2002 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-12431067

RESUMEN

Ligands for the glucocorticoid receptor labeled with high-energy isotopes are highly desired for their potential applications in nuclear medical studies of the brain where the dysregulation of this receptor system is thought to be involved in various neurodegenerative disorders. Analogues of the glucocorticoid cortivazol have previously been prepared as target compounds for labeling with high-energy isotopes. However, the phenyl rings of arylpyrazoles of this type are not sufficiently activated for nucleophilic substitution reactions that are generally required for the synthesis of radiohalogenated analogues. Since suitably substituted aromatic nitrogen heterocyclic groups are amenable to nucleophilic substitution, the goal of this study was the synthesis of pyridylpyrazolo and pyrimidylpyrazolo analogues similar to cortivazol that could be labeled with radiohalogens in the pyridine or pyrimidine rings. We describe the synthesis of several [3,2-c]pyrazolo steroids containing pyridyl, halopyridyl, and pyrimidyl substituents at the 2' position of the pyrazole ring. These compounds were tested for binding to the glucocorticoid receptor and for biological activity in glucocorticoid responsive HeLa cells grown in tissue culture. Of the pyridyl and pyrimidyl derivatives, 2'-(3-pyridyl)-11 beta,17,21-trihydroxy-16 alpha-methyl-20-oxopregn-4-eno[3,2-c]pyrazole showed superior activity in both assays and it was used as the basis for the synthesis of several analogues that were halogenated in the pyridine ring. These halogenated compounds were all tested for their binding to the glucocorticoid receptor and for their biological activity. One, a fluorinated compound 2'-(2-fluoro-5-pyridyl)-11 beta,17,21-trihydroxy-16 alpha-methyl-20-oxopregn-4-eno[3,2-c]pyrazole had excellent activity, considerably better than the potent glucocorticoid dexamethasone. Most importantly, fluorination was achieved using a nucleophilic exchange reaction, a method that is adaptable to radiolabeling with the positron-emitting isotope fluorine-18. Thus, considering its superior biological activity and adaptability for facile radiosynthesis, this target compound has the potential for imaging of glucocorticoid receptor containing tissues using positron emission tomography.


Asunto(s)
Glucocorticoides/síntesis química , Pregnenos/síntesis química , Pirazoles/síntesis química , Radiofármacos/síntesis química , Receptores de Glucocorticoides/metabolismo , Fosfatasa Alcalina/biosíntesis , Animales , Unión Competitiva , Inducción Enzimática , Radioisótopos de Flúor , Glucocorticoides/química , Glucocorticoides/metabolismo , Células HeLa , Humanos , Técnicas In Vitro , Marcaje Isotópico , Ligandos , Pregnenos/química , Pregnenos/metabolismo , Pirazoles/química , Pirazoles/metabolismo , Radiofármacos/química , Radiofármacos/metabolismo , Ratas
20.
J Steroid Biochem Mol Biol ; 78(5): 493-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11738559

RESUMEN

When Bacillus stearothermophilus, a thermophilic bacterium isolated from the Kuwaiti desert, was incubated with exogenous progesterone for 24 h, three monohydroxylated metabolites were produced. 20alpha-Hydroxyprogesterone was the major metabolite produced in 60.8 relative percentage yield. The other two monohydroxylated metabolites were identified as 6beta-hydroxyprogesterone and the rare 6alpha-hydroxyprogesterone in 21.0 and 13.6 relative percentage yields, respectively. A new metabolite 9,10-seco-4-pregnene-3,9,20-trione was isolated in 3.7 relative percentage yield. All metabolites were purified by preparative TLC and HPLC followed by their identification using 1H, 13C NMR and other spectroscopic data.


Asunto(s)
Geobacillus stearothermophilus/metabolismo , Pregnenos/metabolismo , Progesterona/metabolismo , Biotransformación , Cromatografía Líquida de Alta Presión , Clima Desértico , Geobacillus stearothermophilus/aislamiento & purificación , Kuwait , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Pregnenos/química , Progesterona/química , Microbiología del Suelo , Espectroscopía Infrarroja por Transformada de Fourier
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