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1.
Graefes Arch Clin Exp Ophthalmol ; 257(11): 2429-2436, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31512044

RESUMEN

PURPOSE: Diabetic retinopathy (DR) is a complex eye disease associated with diabetes mellitus. It is characterized by three pathophysiological components, namely microangiopathy, neurodegeneration, and inflammation. We recently reported that intraperitoneal administration of BNN27, a novel neurosteroidal microneurotrophin, reversed the diabetes-induced neurodegeneration and inflammation in rats treated with streptozotocin (STZ), by activating the NGF TrkA and p75 receptors. The aim of the present study was to investigate the efficacy of BNN27 to protect retinal neurons when applied topically as eye drops in the same model. METHODS: The STZ rat model of DR was employed. BNN27 was administered as eye drops to diabetic Sprague-Dawley rats for 7 days, 4 weeks post-STZ (70 mg/kg) injection. Immunohistochemistry and western blot analyses were employed to examine the viability of retinal neurons in control, diabetic, and diabetic-treated animals and the involvement of the TrkA receptor and its downstream signaling ERK1/2 kinases, respectively. RESULTS: BNN27 reversed the STZ-induced attenuation of the immunoreactive brain nitric oxide synthetase (bNOS)- and tyrosine hydroxylase (TH)-expressing amacrine cells and neurofilament (NFL)-expressing ganglion cell axons in a dose-dependent manner. In addition, BNN27 activated/phosphorylated the TrkA receptor and its downstream prosurvival signaling pathway, ERK1/2 kinases. CONCLUSIONS: The results of this study provide solid evidence regarding the efficacy of BNN27 as a neuroprotectant to the diabetic retina when administered topically, and suggest that its pharmacodynamic and pharmacokinetic profiles render it a putative therapeutic for diabetic retinopathy.


Asunto(s)
Deshidroepiandrosterona/administración & dosificación , Diabetes Mellitus Experimental , Retinopatía Diabética/tratamiento farmacológico , Retina/patología , Administración Tópica , Animales , Western Blotting , Deshidroepiandrosterona/farmacocinética , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Retina/efectos de los fármacos , Retina/metabolismo , Resultado del Tratamiento
2.
Prague Med Rep ; 116(1): 40-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25923969

RESUMEN

Eight women of reproductive age with normal body mass index were given 5 standardised meals, and their hormonal milieu was determined during the course of the day. Plasma from 12 withdrawals was analysed for dehydroepiandrosterone and its 7- and 16-hydroxylated metabolites. Overall, there was a maximum in the levels of steroid hormones in the morning, followed by decreases throughout the day. There was also an additional significant decrease found for dehydroepiandrosterone and its 7α-hydroxyderivative in association with the consumption of main meals, but not for the 7ß-isomer or 16α-hydroxyderivative.


Asunto(s)
Deshidroepiandrosterona/farmacocinética , Ingestión de Alimentos/efectos de los fármacos , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/farmacocinética , Adulto , Deshidroepiandrosterona/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Hidroxilación
3.
Eur J Contracept Reprod Health Care ; 18(6): 489-500, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23944295

RESUMEN

BACKGROUND: Combined oral contraceptives (COCs) reduce the levels of ovarian and adrenal androgens. Co-administration of dehydroepiandrosterone (DHEA) may normalise androgen levels during COC use. OBJECTIVE: To investigate the effect of the addition of DHEA to a COC on the pharmacokinetics (PK) and pharmacodynamics (PD) of DHEA and its sulphate (DHEA-S), and on levels of total and free testosterone (T). METHODS: In a prospective, randomised, double-blind, placebo-controlled, cross-over study involving 21 female volunteers, the PK and PD of DHEA and DHEA-S were investigated during the use of one cycle of a COC containing 30 µg ethinylestradiol (EE) and 3 mg drospirenone (DRSP) with and without daily co-administration of 50 mg DHEA. RESULTS: Treatment during one cycle with a COC containing EE and DRSP reduces the exposure to DHEA and DHEA-S by at least 20%. This loss of adrenal androgens can be fully compensated by daily oral co-administration of 50 mg DHEA. With DHEA co-administration total T levels rise significantly (1.44 nmol/L with DHEA vs. 0.82 nmol/L with placebo; p < 0.001). Free T levels decrease significantly with both DHEA and placebo treatment, but significantly less during co-administration of DHEA (6.34 pmol/L with DHEA vs. 3.96 pmol/L with placebo; p < 0.001). CONCLUSION: By adding DHEA to a COC the loss of adrenal and ovarian androgens can be restored.


Asunto(s)
Androstenos/farmacología , Anticonceptivos Orales Combinados/farmacología , Sulfato de Deshidroepiandrosterona/farmacocinética , Deshidroepiandrosterona/farmacocinética , Etinilestradiol/farmacología , Levonorgestrel/farmacología , Testosterona/sangre , Adulto , Análisis de Varianza , Estudios Cruzados , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona/sangre , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Embarazo , Estudios Prospectivos
4.
Steroids ; 173: 108889, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34246664

RESUMEN

Estradiol, an estrogen steroid hormone, serves as the dominant female hormone and its levels fluctuate during lifetime. In women, after the menopause, all estrogens and almost all androgens are locally developed in the peripheral tissues from dehydroepiandrosterone (DHEA). However, the effect of DHEA supplementation on estradiol levels in women is unclear as previously published data has resulted in conflicting findings. Thus, we conducted the present dose-response meta-analysis of randomized controlled trials (RCTs) evaluating the influence of DHEA on estradiol concentrations in women. The PubMed/Medline, Embase, Web of Science and Scopus databases were systematically searched for articles published on this topic until May 10, 2021. No time or language restrictions were applied. The data were expressed as weighted mean differences (WMDs) and 95% confidence intervals (CI), and a P-value of less than 0.05 was considered to be statistically significant. The pooled results were obtained using the generic inverse of variance method with a random effects model. A total of 21 arms, including 1223 participants (case = 610, and control = 613), reported estradiol concentrations as an outcome measure. The overall results demonstrated that estradiol significantly increased following the administration of DHEA (WMD: 7.02 pg/mL, 95% CI: 5.43, 8.62, P = 0.000). The stratified analyses revealed that the elevation of estradiol concentrations was more pronounced in subjects aged ≥60 years old (WMD: 8.56 pg/mL, 95% CI: 6.97, 10.16, I2 = 94%) and in those receiving DHEA supplements for ≥26 weeks (WMD: 7.30 pg/mL, 95% CI: 6.28, 8.32, I2 = 61%). Moreover, estradiol levels increased significantly with DHEA dosages of 50 mg/day (WMD: 7.75 pg/mL, 95% CI: 9.12, 9.39, I2 = 94%) and when DHEA was prescribed to postmenopausal women (WMD: 7.61 pg/mL, 95% CI: 5.97, 9.24, I2 = 93%). This meta-analysis has provided a comprehensive overview of the effects of DHEA administration on circulating estradiol levels, far beyond the available evidence from different RCTs. Subsequent subgroup analyses revealed that postmenopausal women, females aged 60 years and above, those on DHEA dosages of 50 mg/day and those receiving DHEA for ≥26 weeks registered a more pronounced elevation of the circulating estradiol levels.


Asunto(s)
Deshidroepiandrosterona/uso terapéutico , Suplementos Dietéticos , Estradiol/sangre , Posmenopausia/sangre , Anciano , Deshidroepiandrosterona/farmacocinética , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia/efectos de los fármacos , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
Pharmacol Res Perspect ; 9(2): e00724, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33638308

RESUMEN

BNN27 is a novel 17-spiroepoxy derivative of the neurosteroid Dehydroepiandrosterone with neuroprotective properties. The purpose of this study was the detection and quantification of BNN27 after single intraperitoneal administration, in the serum and retina of normal rodents. Forty-two C57BL/6 mice and 48 Sprague-Dawley rats were used for the quantification of BNN27 in the blood serum and retina, respectively. BNN27 was injected intraperitoneally (i.p.) at concentrations of 100 and 30 mg/kg of body weight (b.w.), respectively. The blood was collected with retro-orbital bleeding and the retina was isolated after enucleation at various time points. The molecule concentrations were measured with Liquid chromatography-mass spectrometry (LC-MS). Non-compartmental analysis was used to determine pharmacokinetic parameters. BNN27 was found to have an elimination constant kel  = 0.465 h-1 and mean residence time (MRT) 2.154 h in the mouse serum. The maximum concentration (Cmax ) in the retina was detected at 2 h ( tCmax ) after intraperitoneal administration and was equal to 1100 ng/g. BNN27 is rapidly eliminated from both blood and retina. In the retina specifically, it is undetectable 6 h after injection. BNN27 shows a rapid systemic elimination as anticipated by its small size and lipophilicity. It is measurable in small peripheral tissues such as the rat retina, after one single i.p. injection, using a simple method such as LC-MS. Its detection in the retina corroborates the existing biological data that the molecule crosses the blood-retinal barrier, highlighting it as a potential neuroprotective agent for retinal disease.


Asunto(s)
Deshidroepiandrosterona/farmacocinética , Fármacos Neuroprotectores/farmacocinética , Animales , Área Bajo la Curva , Barrera Hematorretinal/metabolismo , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/análisis , Femenino , Inyecciones Intraperitoneales , Masculino , Tasa de Depuración Metabólica , Ratones , Modelos Animales , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/análisis , Permeabilidad , Ratas , Retina/química , Distribución Tisular
6.
J Pharmacol Exp Ther ; 333(1): 70-80, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20068030

RESUMEN

Insulin resistance, the major metabolic abnormality underlying type 2 diabetes, is associated with chronic inflammation and heavy macrophage infiltration in white adipose tissue (WAT). The therapeutic properties of the synthetic adrenal steroid Delta(5)-androstene-17alpha-ethynyl-3beta,7beta,17beta-triol (HE3286) were characterized in metabolic disease models. Treatment of diabetic db/db mice with HE3286 suppressed progression to hyperglycemia and markedly improved glucose clearance. Similar effects were also observed in insulin-resistant, diet-induced obese C57BL/6J mice and genetically obese ob/ob mice. This effect appeared to be a consequence of reduced insulin resistance because HE3286 lowered blood insulin levels in db/db and ob/ob mice. Treatment with HE3286 was accompanied by suppressed expression of the prototype macrophage-attracting chemokine monocyte chemoattractant protein-1 in WAT, along with its cognate receptor C-C motif chemokine receptor-2. Exposure of mouse macrophages to HE3286 in vitro caused partial suppression of endotoxin (lipopolysaccharide)-induced nuclear factor kappa-B (NF-kappaB)-sensitive reporter gene expression, NF-kappaB nuclear translocation, and NF-kappaB/p65 serine phosphorylation. Proinflammatory kinases, including IkappaB kinase, c-Jun NH2-terminal kinase, and p38, were also inhibited by HE3286. In ligand competition experiments HE3286 did not bind to classical sex steroid or corticosteroid receptors, including androgen receptor (AR), progesterone receptor, estrogen receptor (ER) alpha or ERbeta, and glucocorticoid receptor (GR). Likewise, in cells expressing nuclear receptor-sensitive reporter genes HE3286 did not substantially stimulate transactivation of AR, ER, GR, or peroxisome proliferator-activated receptor (PPAR) alpha, PPARdelta, and PPARgamma. These findings indicate that HE3286 improves glucose homeostasis in diabetic and insulin-resistant mice and suggest that the observed therapeutic effects result from attenuation of proinflammatory pathways, independent of classic sex steroid receptors, corticosteroid receptors, or PPARs.


Asunto(s)
Antiinflamatorios/farmacología , Deshidroepiandrosterona/análogos & derivados , Hipoglucemiantes/farmacología , Animales , Antiinflamatorios/farmacocinética , Línea Celular , Deshidroepiandrosterona/farmacocinética , Deshidroepiandrosterona/farmacología , Perfilación de la Expresión Génica , Intolerancia a la Glucosa/metabolismo , Intolerancia a la Glucosa/prevención & control , Hiperglucemia/metabolismo , Hiperglucemia/prevención & control , Hipoglucemiantes/farmacocinética , Resistencia a la Insulina , Lipopolisacáridos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , FN-kappa B/metabolismo , Fosforilación , Receptores de Esteroides/biosíntesis , Receptores de Esteroides/genética
7.
Drug Metab Dispos ; 37(5): 1089-97, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19196848

RESUMEN

The objective of this research was the identification of the metabolic profile of fluasterone, a synthetic derivative of dehydroepiandrosterone, in dogs treated orally or subcutaneously with [4-(14)C]fluasterone. Separation and characterization techniques used to identify the principal metabolites of fluasterone in urine and feces included high-performance liquid chromatography (HPLC), liquid scintillation spectrometry, HPLC/tandem mass spectrometry, and NMR. In urine, the majority of the radioactivity was present as two components that had apparent molecular weights consistent with their tentative identification as monoglucuronide conjugates of 4alpha-hydroxy-16alpha-fluoro-5-androsten-17beta-ol and X(alpha or beta)-4alpha-dihydroxy-16alpha-fluoro-5-androsten-17beta-ol. The identification of the monoglucuronide conjugate of 4alpha-hydroxy-16alpha-fluoro-5-androsten-17beta-ol was also supported by NMR data. In support of this identification, these metabolites were cleaved with glucuronidase enzyme treatment, which gave rise to components with molecular weights again consistent with the aglycones of a monohydroxylated, 17-keto reduced (dihydroxy) fluasterone metabolite and a dihydroxylated, 17-keto reduced (trihydroxy) fluasterone metabolite. In feces, nonconjugated material predominated. The primary metabolites eliminated in feces were the two hydroxy fluasterone metabolites arising from 17-reduction (16alpha-fluoro-5-androsten-17beta-ol and 16alpha-fluoro-5-androsten-17alpha-ol) and 4alpha-hydroxy-16alpha-fluoro-5-androsten-17beta-ol that was present in urine in glucuronide form.


Asunto(s)
Antineoplásicos/farmacocinética , Deshidroepiandrosterona/análogos & derivados , Heces/química , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/orina , Biotransformación , Cromatografía Líquida de Alta Presión , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/farmacocinética , Deshidroepiandrosterona/orina , Perros , Eritrocitos/metabolismo , Glucuronidasa/metabolismo , Glucurónidos/metabolismo , Inyecciones Subcutáneas , Espectroscopía de Resonancia Magnética , Masculino , Espectrometría de Masas , Sulfatasas/metabolismo
8.
Gynecol Obstet Invest ; 66(2): 111-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18446040

RESUMEN

BACKGROUND/AIMS: There is a lack of evidence in the literature supporting vaginal application of a combination hormone-containing cream for local and systemic symptom relief. This pilot study examined the extent of absorption of a single cream containing estriol, estradiol, progesterone, DHEA, and testosterone. METHODS: A combination cream was administered to 12 postmenopausal women in two differing doses over two independent time periods. Following 28 days (arm 1) and an additional 14 days (arm 2), measurement of hormones in saliva and blood and measurements of symptom relief, patient tolerability, and health-related quality of life (HRQoL) were obtained. RESULTS: The dosage and time of evaluation for study arm 1 was not ideal for providing documented increases in hormone levels. HRQoL measurements supported measured improvement in this arm. The second arm did document absorption of the various hormones when given vaginally. CONCLUSION: This study is the first documenting systemic absorption of multiple hormones by both saliva and blood as well as improvement of HRQoL. This therapy was generally well-tolerated with only 2 patients experiencing minor irritation, not necessitating discontinuation. Additional studies in larger numbers of patients will provide better knowledge for clinicians wanting to provide similar therapy at the lowest effective dose.


Asunto(s)
Hormonas Esteroides Gonadales/administración & dosificación , Hormonas Esteroides Gonadales/farmacocinética , Terapia de Reemplazo de Hormonas/métodos , Membrana Mucosa/metabolismo , Vagina/metabolismo , Administración Intravaginal , Adsorción , Anciano , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/sangre , Deshidroepiandrosterona/farmacocinética , Emolientes/administración & dosificación , Emolientes/farmacocinética , Estradiol/administración & dosificación , Estradiol/sangre , Estradiol/farmacocinética , Estriol/administración & dosificación , Estriol/sangre , Estriol/farmacocinética , Femenino , Hormonas Esteroides Gonadales/sangre , Humanos , Persona de Mediana Edad , Proyectos Piloto , Calidad de Vida , Saliva/metabolismo , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/farmacocinética
9.
J Clin Invest ; 94(4): 1484-9, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7929824

RESUMEN

To test the hypothesis that insulin acutely enhances the metabolic clearance rate (MCR) of dehydroepiandrosterone in humans, the effect of a short-term insulin infusion on the MCR of dehydroepiandrosterone was assessed in 10 men and 7 women. After an overnight fast, dehydroepiandrosterone was infused at 3.47 mumol/h for 6.5 h. At 240 min, a hyperinsulinemic-euglycemic clamp was begun by infusing insulin at 21.5 pmol/kg per min for 2.5 h. MCR of dehydroepiandrosterone was calculated at baseline (210-240 min) and during the insulin infusion (360-390 min). A control study was conducted at least 1 wk later, in which 0.45% saline was substituted for the hyperinsulinemic-euglycemic clamp. During the insulin clamp study, serum insulin rose from 34 +/- 2 to 1084 +/- 136 pmol/liter (P = 0.0001) in men and from 40 +/- 5 to 1357 +/- 175 pmol/liter (P = 0.0003) in women, while serum glucose remained constant in both groups. MCR of dehydroepiandrosterone rose in men during the insulin infusion from 2443 +/- 409 to 3599 +/- 500 liters/24 h (P = 0.003), but did not change during the control saline infusion. In contrast, MCR of dehydroepiandrosterone in women did not change in the insulin clamp study during insulin infusion (2526 +/- 495 liters/24 h at baseline vs. 2442 +/- 491 liters/24 h during insulin infusion; P = 0.78). These findings suggest that insulin acutely increases the MCR of dehydroepiandrosterone in men but not in women.


Asunto(s)
Deshidroepiandrosterona/farmacocinética , Insulina/farmacología , Caracteres Sexuales , Adulto , Glucemia/análisis , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/sangre , Femenino , Humanos , Infusiones Intravenosas , Insulina/administración & dosificación , Insulina/sangre , Masculino , Tasa de Depuración Metabólica/efectos de los fármacos
10.
AIDS Res Hum Retroviruses ; 23(1): 77-85, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17263636

RESUMEN

Prior studies have indicated that dehydroepiandrosterone (DHEA) may have immunomodulatory properties as well as positive effects on mood, quality of life, and body composition. Preliminary data suggest that DHEA inhibits expression of human immunodeficiency virus 1 (HIV) in latently infected cells; thus, it might be a potential adjunct to currently available antiretroviral therapy. The objective was to determine DHEA's impact on latent HIV infection, persistent viral replication, immunity, and nonimmune aspects of health restoration. A randomized, double-blind, placebo-controlled 24-week outpatient intervention included 40 subjects with suppressed HIV viremia on a stable antiretroviral regimen. Participants were randomized with equal probability to receive either DHEA or placebo for 12 weeks, followed by open-label DHEA for an additional 12 weeks. Intensive virologic monitoring included plasma viral load assays (lower limits of detection 50 copies/ml and 2.5 copies/ml) and quantitative cultures of replication-competent virus reservoirs in blood cells. A full battery of immunologic measurements was performed. Measurements of hormones, body weight, and body composition were obtained. Quality of life was assessed using validated questionnaires. DHEA was bioavailable as ascertained by increased levels of DHEA, DHEA(S), and androstenedione in recipients' plasma compared to the control group. The titers of infectious HIV culturable from blood trended upward in the DHEA arm although there was no significant change in plasma HIV RNA level. No significant immune effects were observed with DHEA. There appeared to be no benefit with regard to lean muscle mass or bone density in the DHEA recipients. DHEA treatment had a positive impact on overall quality of life. DHEA supplementation in fully suppressed HIV patients was associated with an improvement in quality of life but appeared to have no beneficial antiviral, immunomodulatory, hormonal, or body composition effects, suggesting that it not be routinely used as an adjunctive therapy in this population.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Deshidroepiandrosterona/farmacología , Deshidroepiandrosterona/farmacocinética , Infecciones por VIH/inmunología , Replicación Viral/inmunología , Adulto , Negro o Afroamericano/estadística & datos numéricos , Disponibilidad Biológica , Método Doble Ciego , Femenino , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , ARN Viral/sangre , Encuestas y Cuestionarios , Carga Viral , Población Blanca/estadística & datos numéricos
11.
Steroids ; 72(1): 71-84, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17157339

RESUMEN

HYPOTHESIS: A cortisol response to adrenocorticotropin injection is the standard test for diagnosing adrenal insufficiency. Multiple steroid hormones can now be accurately measured by tandem mass spectrometry in a single sample. The study objective was to determine whether a steroid profile, created by simultaneous measurement of 10 steroid hormones by tandem mass spectrometry, would help determine the cause of adrenal insufficiency. DESIGN: A 10-steroid profile was measured by tandem mass spectrometry during the performance of a standard high dose cortrosyn stimulation test. The steroids were measured at baseline, 30, and 60min following synthetic adrenocorticotropin injection. Adrenal insufficiency was defined as a peak cortisol level of less than 20microg/dL. Testing was conducted in the general clinical research center of a university medical center. Normal volunteers, patients suspected of having adrenal insufficiency, and patients with known adrenal insufficiency participated. RESULTS: Our results showed that adrenal insufficiency of any cause was adequately diagnosed using the response of 11-deoxycortisol, dehydroepiandrosterone, or these analytes combined in a two-steroid profile. A three-steroid profile yielded a test with 100% accuracy for discriminating primary adrenal insufficiency from normal status. Primary adrenal insufficiency was well separated from secondary adrenal insufficiency using only a single aldosterone value. 11-Deoxycortisol, dehydroepiandrosterone, and a two-steroid profile each provided fair discrimination between secondary adrenal insufficiency and normal status. CONCLUSIONS: We conclude that stimulated levels of aldosterone, 11-deoxycortisol, dehydroepiandrosterone, and a two- or three-steroid profile provided additional discrimination between states of adrenal sufficiency and insufficiency. It is proposed that a steroid profile measuring cortisol, aldosterone, 11-deoxycortisol, and dehydroepiandrosterone would potentially improve the ability to determine the cause of adrenal insufficiency.


Asunto(s)
Corticoesteroides/sangre , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/etiología , Hormona Adrenocorticotrópica , Corticoesteroides/análisis , Insuficiencia Suprarrenal/sangre , Adulto , Aldosterona/sangre , Aldosterona/farmacocinética , Cromatografía Líquida de Alta Presión , Cortodoxona/sangre , Cortodoxona/farmacocinética , Deshidroepiandrosterona/sangre , Deshidroepiandrosterona/farmacocinética , Femenino , Humanos , Hidrocortisona/sangre , Hidrocortisona/farmacocinética , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estimulación Química , Espectrometría de Masas en Tándem
12.
Int J Pharm ; 337(1-2): 25-30, 2007 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-17482394

RESUMEN

A sensitive analytical method for the determination of a new active steroid, butane acid-(5-androsten-17-one-3beta-ol)-diester (A1998), was developed by high performance liquid chromatography with laser-induced fluorescence detection following the pre-column derivatization with dansylhydrazine. The calibration curve for A1998 derivatization was found linear in the dynamic range from 0.025 to 5.0 microg/ml, with the precision less than 6% (CV) and the mean extraction efficiency greater than 92%. In 200 microl of plasma samples the limit of quantitation was as low as 0.025 microg/ml with a signal-to-noise ratio of 10. This assaying was further applied to the determination of the pharmacokinetic parameters of A1998 in rats with an intravenous injection of A1998. Values for clearance for elimination, volume of distribution at steady state and terminal half life in the above case were determined as 50.3+/-1.1 ml/min kg, 1329.0+/-111.0 ml/kg and 44.0+/-2.7 min, respectively.


Asunto(s)
Antiarrítmicos/sangre , Cromatografía Líquida de Alta Presión , Deshidroepiandrosterona/sangre , Evaluación Preclínica de Medicamentos/métodos , Rayos Láser , Espectrometría de Fluorescencia , Animales , Antiarrítmicos/administración & dosificación , Antiarrítmicos/química , Antiarrítmicos/farmacocinética , Disponibilidad Biológica , Calibración , Catálisis , Compuestos de Dansilo/química , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/análogos & derivados , Deshidroepiandrosterona/química , Deshidroepiandrosterona/farmacocinética , Evaluación Preclínica de Medicamentos/normas , Femenino , Colorantes Fluorescentes/química , Semivida , Hidrazinas/química , Inyecciones Intravenosas , Tasa de Depuración Metabólica , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Temperatura , Factores de Tiempo , Ácido Trifluoroacético/química
13.
Nat Nanotechnol ; 12(12): 1183-1189, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28825714

RESUMEN

Achieving triggered release of small molecules with spatial and temporal precision at designated cells within an organism remains a challenge. By combining a cell-targetable, icosahedral DNA-nanocapsule loaded with photoresponsive polymers, we show cytosolic delivery of small molecules with the spatial resolution of single endosomes in specific cells in Caenorhabditis elegans. Our technology can report on the extent of small molecules released after photoactivation as well as pinpoint the location at which uncaging of the molecules occurred. We apply this technology to release dehydroepiandrosterone (DHEA), a neurosteroid that promotes neurogenesis and neuron survival, and determined the timescale of neuronal activation by DHEA, using light-induced release of DHEA from targeted DNA nanocapsules. Importantly, sequestration inside the DNA capsule prevents photocaged DHEA from activating neurons prematurely. Our methodology can in principle be generalized to diverse neurostimulatory molecules.


Asunto(s)
Caenorhabditis elegans/metabolismo , ADN/química , Deshidroepiandrosterona , Nanocápsulas/química , Animales , Caenorhabditis elegans/citología , Supervivencia Celular/efectos de los fármacos , Deshidroepiandrosterona/química , Deshidroepiandrosterona/farmacocinética , Deshidroepiandrosterona/farmacología , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Neurogénesis/efectos de los fármacos , Neuronas/citología , Neuronas/metabolismo
14.
Psychopharmacology (Berl) ; 188(4): 541-51, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16231168

RESUMEN

RATIONALE: Dehydroepiandrosterone (DHEA) has been reported to enhance cognition in rodents, although there are inconsistent findings in humans. OBJECTIVES: The aim of this study was to investigate the effects of DHEA administration in healthy young men on episodic memory and its neural correlates utilising an event-related potential (ERP) technique. METHODS: Twenty-four healthy young men were treated with a 7-day course of oral DHEA (150 mg b.d.) or placebo in a double blind, random, crossover and balanced order design. Subjective mood and memory were measured using visual analogue scales (VASs). Cortisol concentrations were measured in saliva samples. ERPs were recorded during retrieval in an episodic memory test. Low-resolution brain electromagnetic tomography (LORETA) was used to identify brain regions involved in the cognitive task. RESULTS: DHEA administration led to a reduction in evening cortisol concentrations and improved VAS mood and memory. Recollection accuracy in the episodic memory test was significantly improved following DHEA administration. LORETA revealed significant hippocampal activation associated with successful episodic memory retrieval following placebo. DHEA modified ERPs associated with retrieval and led to a trend towards an early differential activation of the anterior cingulate cortex (ACC). CONCLUSIONS: DHEA treatment improved memory recollection and mood and decreased trough cortisol levels. The effect of DHEA appears to be via neuronal recruitment of the steroid sensitive ACC that may be involved in pre-hippocampal memory processing. These findings are distinctive, being the first to show such beneficial effects of DHEA on memory in healthy young men.


Asunto(s)
Afecto/efectos de los fármacos , Deshidroepiandrosterona/farmacología , Hidrocortisona/metabolismo , Memoria/efectos de los fármacos , Adolescente , Adulto , Afecto/fisiología , Estudios Cruzados , Deshidroepiandrosterona/farmacocinética , Método Doble Ciego , Electroencefalografía , Humanos , Masculino , Memoria/fisiología , Saliva/metabolismo
15.
Am J Health Syst Pharm ; 63(22): 2201-10, 2006 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-17090740

RESUMEN

PURPOSE: The pharmacology, pharmacokinetics, clinical efficacy, adverse effects and toxicities, drug interactions, dosage and administration, and safety issues related to the use of prasterone are discussed. SUMMARY: Prasterone is a proprietary synthetic dehydroepiandrosterone product under investigation for use in women with systemic lupus erythematosus (SLE) who are taking glucocorticoids. Initial trials investigated prasterone as a treatment to improve disease activity and symptoms in women with mild to moderate SLE. The Food and Drug Administration (FDA) did not approve prasterone's labeling for these indications. Subsequent trials have focused on prasterone as a treatment to limit bone loss in women who have SLE. A study was conducted to assess bone mineral density in patients who had been taking glucocorticoids for six months or longer. The patients in the prasterone group showed an increase in bone mineral density, while the placebo group demonstrated a loss. The most common adverse effects of prasterone therapy were acne and hirsutism. Hematuria, hypertension, and serum creatinine concentration increases have also occurred. Interactions of prasterone potentially exist with 5-alpha reductase inhibitors and additive or antagonistic effects could possibly occur with androgens, estrogens, oral contraceptives, and progestins. In clinical trials, oral prasterone dosages of 100-200 mg/day were administered. These dosages have resulted in supraphysiological hormone levels. CONCLUSION: FDA has granted orphan drug status for the prevention of loss of bone mineral density in SLE patients taking glucocorticoids. FDA is requesting additional Phase III trial data for the treatment of SLE and the prevention of loss of bone mineral density.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Deshidroepiandrosterona/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Producción de Medicamentos sin Interés Comercial , Osteoporosis/tratamiento farmacológico , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/efectos adversos , Adyuvantes Inmunológicos/farmacocinética , Adulto , Disponibilidad Biológica , Densidad Ósea/efectos de los fármacos , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/efectos adversos , Deshidroepiandrosterona/farmacocinética , Aprobación de Drogas , Interacciones Farmacológicas , Femenino , Glucocorticoides/efectos adversos , Humanos , Lupus Eritematoso Sistémico/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/inducido químicamente , Guías de Práctica Clínica como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
16.
J Steroid Biochem Mol Biol ; 159: 142-53, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26972555

RESUMEN

This study integrates all data obtained in women aged 40-80years enrolled with moderate to severe symptoms of vulvovaginal atrophy (VVA) who received daily intravaginal administration of 0.50% (6.5mg) dehydroepiandrosterone (DHEA; prasterone) for 12weeks (n=723; ITT-S population) as compared with placebo (n=266; ITT-S population). To this end, serum steroid levels (DHEA, DHEA-sulfate (DHEA-S), androst-5-ene-3ß, 17ß-diol (5-diol), testosterone, dihydrotestosterone (DHT), androstenedione (4-dione), estrone (E1), estradiol (E2), estrone sulfate (E1-S), androsterone glucuronide (ADT-G), and androstane-3α, 17ß-diol 17-glucuronide (3α-diol-17G)) were measured at Day 1 and Week 12 by liquid chromatography-tandem mass spectrometry (LC-MS/MS) following validation performed according to the FDA guidelines [1-6]. In agreement with the mechanisms of intracrinology where DHEA is exclusively transformed intracellularly into active sex steroids which act and are inactivated locally before being released as glucuronided or sulfated metabolites for elimination by the kidneys and liver, all sex steroids remained well within normal postmenopausal values following administration of intravaginal DHEA. Serum estradiol, the most relevant sex steroid, was measured after 12weeks of treatment at 3.36pg/ml (cITT-S population) or 19% below the normal postmenopausal value of 4.17pg/ml. On the other hand, serum E1-S, the best recognized marker of global estrogenic activity, shows an average value of 209pg/ml at 12 weeks compared to 220pg/ml in normal postmenopausal women. Moreover, serum ADT-G, the main metabolite of androgens, also remains well within normal postmenopausal values. The present data shows that a low daily intravaginal dose (6.5mg) of DHEA (prasterone) which is efficacious on the symptoms and signs of VVA, permits to achieve the desired local efficacy without systemic exposure, in agreement with the stringent mechanisms of menopause established after 500 million years of evolution where each cell in each tissue is the master of its sex steroid exposure.


Asunto(s)
Deshidroepiandrosterona/administración & dosificación , Estradiol/sangre , Posmenopausia/sangre , Testosterona/sangre , Enfermedades Vaginales/tratamiento farmacológico , Administración Intravaginal , Adulto , Anciano , Anciano de 80 o más Años , Atrofia/tratamiento farmacológico , Deshidroepiandrosterona/farmacocinética , Femenino , Terapia de Reemplazo de Hormonas , Humanos , Persona de Mediana Edad
17.
Biochem Pharmacol ; 117: 68-77, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27498123

RESUMEN

Microneurotrophins (MNT's) are small molecule derivatives of dehydroepiandrosterone (DHEA) and do not have significant interactions with sex steroid receptors. MNT's retain high-affinity binding to protein tyrosine kinase (Trk) receptors and can mimic many pleiotropic actions of neurotrophin (NT) proteins on neurons. MNT's offer therapeutic potential for diseases such as amyotrophic lateral sclerosis (ALS) where motor neurons (MN) degenerate. MNT's cross artificial membranes mimicking the blood-brain barrier, are not major substrates for ABC (ATP-binding cassette) transporters and are metabolized rapidly by mouse but more slowly by human hepatocytes. A lead MNT (BNN27) and its mono-oxidation metabolites enter mouse brain rapidly. RNA-sequencing measured gene expression profiles of human H9eSC-(embryonic stem cell)-derived or CTL (control) subject iPSC-(induced pluripotential stem cell)-derived MN's exposed to NT proteins or MNT molecules. Expression ratios (relative to DMSO (dimethylsulfoxide) vehicle) were calculated, and the resulting top 500 gene lists were analyzed for Gene Ontology (GO) grouping using DAVID (Database for Annotation, Visualization and Integrated Discovery). The MNT's BNN20, BNN23, and BNN27 showed overlap of GO terms with NGF (nerve growth factor) and BDNF (brain-derived neurotrophic factor) in the H9eSC-derived MN's. In the iPSC-derived MN's two (BNN20, BNN27) showed overlap of GO terms with NGF or BDNF. Each NT protein had GO terms that did not overlap with any MNT in the MN cell lines.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Deshidroepiandrosterona/análogos & derivados , Drogas en Investigación/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Neuronas Motoras/efectos de los fármacos , Proteínas del Tejido Nervioso/metabolismo , Fármacos Neuroprotectores/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Absorción Fisiológica/efectos de los fármacos , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Animales , Biotransformación , Barrera Hematoencefálica , Células CACO-2 , Línea Celular , Células Cultivadas , Deshidroepiandrosterona/metabolismo , Deshidroepiandrosterona/farmacocinética , Deshidroepiandrosterona/farmacología , Perros , Drogas en Investigación/metabolismo , Drogas en Investigación/farmacocinética , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células de Riñón Canino Madin Darby , Moduladores del Transporte de Membrana/farmacología , Ratones , Neuronas Motoras/citología , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , Proteínas del Tejido Nervioso/genética , Células-Madre Neurales/citología , Células-Madre Neurales/efectos de los fármacos , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/farmacocinética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Distribución Tisular
18.
Cleve Clin J Med ; 72(11): 965-6, 968, 970-1 passim, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16315437

RESUMEN

Deficiency of dehydroepiandrosterone (DHEA) is associated with lupus erythematosus, diabetes mellitus, Alzheimer disease, and some cancers, but we are not yet ready to conclude that prescribing supplemental DHEA is helpful in these or any other conditions. DHEA shows some promise in observational clinical studies and laboratory experiments, but we still need large-scale human studies to answer key questions. For now, we do not have enough evidence to recommend routine treatment with DHEA. As with other supplements, quality control is always a concern, and different brands may contain different amounts of active ingredient.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Deshidroepiandrosterona/administración & dosificación , Suplementos Dietéticos , Adyuvantes Inmunológicos/farmacocinética , Deshidroepiandrosterona/farmacocinética , Humanos , Neoplasias/sangre , Neoplasias/prevención & control
19.
Drug Deliv ; 12(5): 275-80, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16188726

RESUMEN

The permeation ability of a compound is due principally to its concentration in the vehicle and to its aptitude to cross the stratum corneum of the skin. In this work ex-vivo permeation studies on newly developed formulations containing dehydroepiandrosterone (DHEA) were carried out to investigate vehicles that increase drug permeation through the skin. To enhance the solubility of DHEA, its complex form with alpha-cyclodextrin was used. In addition, the two forms (pure drug and complex form) were introduced in hydrophilic (water), lipophilic (paraffin oil), and microemulsion vehicles to evaluate the synergic effect of cyclodextrins and microemulsion vehicles on solubility and permeation. From the results, DHEA solubility is notably conditioned by the type of the vehicle used: the highest solubilities (both for pure and complex drug forms) were obtained with microemulsion, followed by paraffin oil and water. Moreover, in all the studied vehicles, the c-DHEA was more soluble than DHEA. Permeation profile fluxes showed very interesting differences. That reflect the varying drug forms (pure drug and complex form), vehicles used, and drug concentrations in the vehicles. The major flux was obtained in complex of DHEA with alpha-cyclodextrins in the microemulsion vehicle. Therefore, this type of vehicle and drug form would be very useful in the development of a topical formulation containing DHEA.


Asunto(s)
Deshidroepiandrosterona/administración & dosificación , Piel/metabolismo , alfa-Ciclodextrinas/administración & dosificación , Animales , Deshidroepiandrosterona/química , Deshidroepiandrosterona/farmacocinética , Masculino , Permeabilidad , Vehículos Farmacéuticos , Solubilidad , Porcinos
20.
J Chromatogr Sci ; 43(1): 32-8, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15808004

RESUMEN

The use of gas chromatography (GC)-combustion (C)-isotope ratio mass spectrometry (IRMS) demonstrates that a single oral administration of dehydroepiandrosterone (DHEA, 100 mg) to a male subject significantly lowers the 13C content of etiocholanolone (Et) and androsterone (A) in the subject's urine. The difference in carbon isotope ratio (d13C per thousand) values between Et and A increases from 1.6 per thousand at the time of administration to 5.1 per thousand at 26 h post-administration, indicating preferential metabolism of administered DHEA to form Et in relation to A. Multiple oral administrations of DHEA to a male subject reveals lower d13C values during the excretion period of Et (-31.7 per thousand to -34.6 per thousand) and A (-31.4 per thousand to -33.0 per thousand) to that of the d13C value of the administered DHEA (-31.3 per thousand). Reference distributions of d13C Et and d13C A constructed from normal athlete populations within Australia and New Zealand show a small natural discrimination against 13C in the formation of Et relative to A (mean=0.3 per thousand, n=167, p=0.007). Amplified differences between d13C Et and d13C A, and in vivo 13C depletion measured by GC-C-IRMS are shown to be potentially useful for doping control.


Asunto(s)
Anabolizantes/aislamiento & purificación , Andrógenos/aislamiento & purificación , Fraccionamiento Químico/métodos , Doping en los Deportes/prevención & control , Adulto , Androsterona/orina , Australia , Isótopos de Carbono/orina , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/farmacocinética , Etiocolanolona/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Masculino , Nueva Zelanda , Deportes
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