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1.
Toxicol Appl Pharmacol ; 486: 116919, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38580201

RESUMEN

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a disease characterized by elevated intracranial pressure (ICP) and is a disease of young females. The first line pharmacological treatments include acetazolamide and topiramate and given the nature of IIH patients and the dosing regimen of these drugs, their effect on the endocrine system is important to evaluate. We aimed to assess the effects of acetazolamide and topiramate on steroid profiles in relevant endocrine tissues. METHODS: Female Sprague Dawley rats received chronic clinically equivalent doses of acetazolamide or topiramate by oral gavage and were sacrificed in estrus. Tissue specific steroid profiles of lateral ventricle CP, 4th ventricle CP, CSF, serum, uterine horn and fundus, ovaries, adrenal glands and pituitary glands were assessed by quantitative targeted LC-MS/MS. We determined luteinizing hormone (LH) and follicle stimulating hormones (FSH) levels in paired serum by ELISA. RESULTS: Topiramate increased the concentration of estradiol and decreased the concentration of DHEA in lateral choroid plexus. Moreover, it decreased the concentration of androstenediol in the pituitary gland. Topiramate increased serum LH. Acetazolamide decreased progesterone levels in serum and uterine fundus and increased corticosteroid levels in the adrenal glands. CONCLUSION: These results demonstrate that both acetazolamide and topiramate have endocrine disrupting effects in rats. Topiramate primarily targeted the choroid plexus and the pituitary gland while acetazolamide had broader systemic effects. Furthermore, topiramate predominantly targeted sex hormones, whereas acetazolamide widely affected all classes of hormones. A similar effect in humans has not yet been documented but these concerning findings warrants further investigations.


Asunto(s)
Acetazolamida , Disruptores Endocrinos , Estro , Ratas Sprague-Dawley , Topiramato , Animales , Femenino , Topiramato/farmacología , Acetazolamida/farmacología , Acetazolamida/toxicidad , Disruptores Endocrinos/toxicidad , Ratas , Estro/efectos de los fármacos , Hormona Luteinizante/sangre , Fructosa/toxicidad , Fructosa/análogos & derivados , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Progesterona/sangre , Hormona Folículo Estimulante/sangre , Hormonas Esteroides Gonadales/sangre , Estradiol/sangre , Ovario/efectos de los fármacos , Ovario/metabolismo
3.
Fluids Barriers CNS ; 21(1): 10, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273331

RESUMEN

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a syndrome exhibiting elevated intracranial pressure (ICP), visual disturbances, and severe headache. IIH primarily affects young obese women, though it can occur in individuals of any age, BMI, and sex. IIH is characterized by systemic metabolic dysregulation with a profile of increased androgen hormones. However, the contribution of obesity/hormonal perturbations to cerebrospinal fluid (CSF) dynamics remains unresolved. METHODS: We employed obese female Zucker rats and adjuvant testosterone to reveal IIH causal drivers. ICP and CSF dynamics were determined with in vivo experimentation and magnetic resonance imaging, testosterone levels assessed with mass spectrometry, and choroid plexus function revealed with transcriptomics. RESULTS: Obese rats had undisturbed CSF testosterone levels and no changes in ICP or CSF dynamics. Adjuvant testosterone treatment of obese rats elevated the CSF secretion rate, although with no effect on the ICP, due to elevated CSF drainage capacity of these rats. CONCLUSIONS: Obesity in itself therefore does not suffice to recapitulate the IIH symptoms in rats, but modulation of CSF dynamics appears with adjuvant testosterone treatment, which mimics the androgen excess observed in female IIH patients. Obesity-induced androgen dysregulation may thus contribute to the disease mechanism of IIH and could potentially serve as a future therapeutic target.


Asunto(s)
Seudotumor Cerebral , Humanos , Femenino , Ratas , Animales , Andrógenos , Ratas Zucker , Obesidad , Testosterona
4.
Environ Res ; 241: 117474, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37879390

RESUMEN

Here, we collected 154 plant species in China ancient forests looking for novel efficient bioactive compounds for cancer treatments. We found 600 bioactive phyto-chemicals that induce apoptosis of liver cancer cell in vitro. First, we screen the plant extract's in vitro cytotoxicity inhibition of cancer cell growth using in vitro HepG2 cell lines and MTT cytotoxicity. The results from these initial MTT in vitro cytotoxicity tests show that the most efficient plants towards hepatoma cytoxicity is Cephalotaxus sinensis, mint bush (Elsholtzia stauntonii) and winged spindle tree (Euonymus alatus). We then used in cell-counting kit-8 (CCK-8) to further understand in vivo tumor growth using nude mice and GC-MS and LC-QTOF-MS to analyze the composition of compounds in the extracts. Extracted chemically active molecules analyzed by network pharmacology showed inhibition on the growth of liver cancer cells by acting on multiple gene targets, which is different from the currently used traditional drugs acting on only one target of liver cancer cells. Extracts from Cephalotaxus sinensis, mint bush (Elsholtzia stauntonii) and winged spindle tree (Euonymus alatus) induce apoptosis in hepatoma cancer cell line HepG2 with a killing rate of more than 83% and a tumor size decrease by 62-67% and a killing rate of only 6% of normal hepatocyte LO2. This study highlight efficient candidate species for cancer treatment providing a basis for future development of novel plant-based drugs to help meeting several of the UN SDGs and planetary health.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Ratones , Animales , Humanos , Células Hep G2 , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Ratones Desnudos , Neoplasias Hepáticas/tratamiento farmacológico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis
5.
Environ Int ; 181: 108279, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37924601

RESUMEN

According to the World Health Organization, women's breast cancer is among the most common cancers with 7.8 million diagnosed cases during 2016-2020 and encompasses 15 % of all female cancer-related mortalities. These mortality events from triple-negative breast cancer are a significant health issue worldwide calling for a continuous search of bioactive compounds for better cancer treatments. Historically, plants are important sources for identifying such new bioactive chemicals for treatments. Here we use high-throughput screening and mass spectrometry analyses of extracts from 100 plant species collected in Chinese ancient forests to detect novel bioactive breast cancer phytochemicals. First, to study the effects on viability of the plant extracts, we used a MTT and CCK-8 cytotoxicity assay employing triple-negative breast cancer (TNBC) MDA-MB-231 and normal epithelial MCF-10A cell lines and cell cycle arrest to estimate apoptosis using flow cytometry for the most potent three speices. Based on these analyses, the final most potent extracts were from the Amur honeysuckle (Lonicera maackii) wood/root bark and Nigaki (Picrasma quassioides) wood/root bark. Then, 5 × 106 MDA-MB-231 cells were injected subcutaneously into the right hind leg of nude mice and a tumour was allowed to grow before treatment for seven days. Subsequently, the four exposed groups received gavage extracts from Amur honeysuckle and Nigaki (Amur honeysuckle wood distilled water, Amur honeysuckle root bark ethanol, Nigaki wood ethanol or Nigaki root bark distilled water/ethanol (1:1) extracts) in phosphate-buffered saline (PBS), while the control group received only PBS. The tumour weight of treated nude mice was reduced significantly by 60.5 % within 2 weeks, while on average killing 70 % of the MDA-MB-231 breast cancer cells after 48 h treatment (MTT test). In addition, screening of target genes using the Swiss Target Prediction, STITCH, STRING and NCBI-gene database showed that the four plant extracts possess desirable activity towards several known breast cancer genes. This reflects that the extracts may kill MBD-MB-231 breast cancer cells. This is the first screening of plant extracts with high efficiency in 2 decades, showing promising results for future development of novel cancer treatments.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama Triple Negativas , Animales , Ratones , Femenino , Humanos , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Extractos Vegetales/farmacología , Extractos Vegetales/química , Neoplasias de la Mama/patología , Ratones Desnudos , Línea Celular Tumoral , Ensayos Analíticos de Alto Rendimiento , Detección Precoz del Cáncer , Apoptosis , Bosques , Etanol , Agua , Proliferación Celular
6.
Fluids Barriers CNS ; 20(1): 44, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328884

RESUMEN

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a condition characterized by increased intracranial pressure (ICP), impaired vision, and headache. Most cases of IIH occur in obese women of childbearing age, though age, BMI, and female sex do not encompass all aspects of IIH pathophysiology. Systemic metabolic dysregulation has been identified in IIH with a profile of androgen excess. However, the mechanistic coupling between obesity/hormonal perturbations and cerebrospinal fluid dynamics remains unresolved. METHODS: Female Wistar rats were either fed a high fat diet (HFD) for 21 weeks or exposed to adjuvant testosterone treatment for 28 days to recapitulate IIH causal drivers. Cerebrospinal fluid (CSF) and blood testosterone levels were determined with mass spectrometry, ICP and CSF dynamics with in vivo experimentation, and the choroid plexus function revealed with transcriptomics and ex vivo isotope-based flux assays. RESULTS: HFD-fed rats presented with increased ICP (65%), which was accompanied by increased CSF outflow resistance (50%) without altered CSF secretion rate or choroid plexus gene expression. Chronic adjuvant testosterone treatment of lean rats caused elevated ICP (55%) and CSF secretion rate (85%), in association with increased activity of the choroid plexus Na+,K+,2Cl- cotransporter, NKCC1. CONCLUSIONS: HFD-induced ICP elevation in experimental rats occurred with decreased CSF drainage capacity. Adjuvant testosterone, mimicking the androgen excess observed in female IIH patients, elevated the CSF secretion rate and thus ICP. Obesity-induced androgen dysregulation may thus contribute to the disease mechanism of IIH.


Asunto(s)
Hipertensión Intracraneal , Seudotumor Cerebral , Femenino , Ratas , Animales , Presión Intracraneal/fisiología , Testosterona , Andrógenos , Dieta Alta en Grasa/efectos adversos , Ratas Wistar , Obesidad/complicaciones
7.
Cephalalgia ; 42(2): 93-107, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34816764

RESUMEN

BACKGROUND: Opening of KATP channels by systemic levcromakalim treatment triggers attacks in migraine patients and hypersensitivity to von Frey stimulation in a mouse model. Blocking of these channels is effective in several preclinical migraine models. It is unknown in what tissue and cell type KATP-induced migraine attacks are initiated and which KATP channel subtype is targeted. METHODS: In mouse models, we administered levcromakalim intracerebroventricularly, intraperitoneally and intraplantarily and compared the nociceptive responses by von Frey and hotplate tests. Mice with a conditional loss-of-function mutation in the smooth muscle KATP channel subunit Kir6.1 were given levcromakalim and GTN and examined with von Frey filaments. Arteries were tested for their ability to dilate ex vivo. mRNA expression, western blotting and immunohistochemical stainings were made to identify relevant target tissue for migraine induced by KATP channel opening. RESULTS: Systemic administration of levcromakalim induced hypersensitivity but central and local administration provided antinociception respectively no effect. The Kir6.1 smooth muscle knockout mouse was protected from both GTN and levcromakalim induced hypersensitivity, and their arteries had impaired dilatory response to the latter. mRNA and protein expression studies showed that trigeminal ganglia did not have significant KATP channel expression of any subtype, whereas brain arteries and dura mater primarily expressed the Kir6.1 + SUR2B subtype. CONCLUSION: Hypersensitivity provoked by GTN and levcromakalim in mice is dependent on functional smooth muscle KATP channels of extracerebral origin. These results suggest a vascular contribution to hypersensitivity induced by migraine triggers.


Asunto(s)
Canales KATP , Trastornos Migrañosos , Adenosina Trifosfato , Animales , Cromakalim/efectos adversos , Modelos Animales de Enfermedad , Humanos , Canales KATP/genética , Canales KATP/metabolismo , Ratones , Ratones Noqueados , Músculo Liso/metabolismo , ARN Mensajero
8.
PLoS One ; 15(12): e0244000, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33320886

RESUMEN

The aim of this study was to investigate the potential interference of cyanobacterial metabolites, in particular microcystins (MCs), with steroid hormone biosynthesis. Steroid hormones control many fundamental processes in an organism, thus alteration of their tissue concentrations may affect normal homeostasis. We used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the modulation of 14 hormones involved in the adrenal steroid biosynthesis pathway using forskolin-treated H295R cells, following exposure with either microcystin-LR (MC-LR) alone, a mixture made up of MC-LR together with eight other MCs and nodularin-R (NOD-R), or extracts from the MC-LR-producing Microcystis aeruginosa PCC7806 strain or its MC-deficient mutant PCC7806mcyB-. Production of 17-hydroxypregnenolone and dehydroepiandrosterone (DHEA) was increased in the presence of MC-LR in a dose-dependent manner, indicating an inhibitory effect on 3ß-hydroxysteroid dehydrogenase (3ß-HSD). This effect was not observed following exposure with a MCs/NOD-R mixture, and thus the effect of MC-LR on 3ß-HSD appears to be stronger than for other congeners. Exposure to extracts from both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- had an opposite effect on 3ß-HSD, i.e. concentrations of pregnenolone, 17-hydroxypregnenolone and DHEA were significantly decreased, showing that there are other cyanobacterial metabolites that outcompete the effect of MC-LR, and possibly result instead in net-induction. Another finding was a possible concentration-dependent inhibition of CYP21A2 or CYP11ß1, which catalyse oxidation reactions leading to cortisol and cortisone, by MC-LR and the MCs/NOD-R mixture. However, both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- extracts had an opposite effect resulting in a substantial increase in cortisol levels. Our results suggest that MCs can modulate steroidogenesis, but the net effect of the M. aeruginosa metabolome on steroidogenesis is different from that of pure MC-LR and independent of MC production.


Asunto(s)
17-alfa-Hidroxipregnenolona/metabolismo , 3-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Deshidroepiandrosterona/biosíntesis , Inhibidores Enzimáticos/farmacología , Microcistinas/farmacología , Microcystis/química , Línea Celular Tumoral , Familia 11 del Citocromo P450/antagonistas & inhibidores , Familia 21 del Citocromo P450/antagonistas & inhibidores , Humanos
9.
Toxicology ; 425: 152247, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31330226

RESUMEN

Azole antifungal drugs are used worldwide to treat a variety of fungal infections such as vulvovaginal candidiasis, particularly in pregnant women who are at increased risk. The aim of this study was to mechanistically investigate the endocrine disrupting potential of four commonly used azole antifungal drugs; clotrimazole, miconazole, ketoconazole and fluconazole in vitro using the H295R cell assay and two recombinant, CYP17A1 and CYP19A1 (aromatase), assays. Steroids were quantified using LC-MS/MS. In both recombinant assays, all four azoles inhibited the CYP enzymes investigated, at therapeutically relevant concentrations. However, responses were much more complex in the H295R cell line. Clotrimazole inhibited steroid production in a dose-dependent manner with IC50 values for CYP17A1 and CYP19A1 in the range 0.017-0.184 µM. Miconazole and ketoconazole increased all steroids on the hydroxylase axis (IC50 MIC: 0.042-0.082 µM, KET: 0.041-1.2 µM), leading to accumulation of progestagens and corticosteroids and suppression of androgens and estrogens, indicating inhibition of CYP17A1, in particular lyase activity. However, ketoconazole suppressed all steroids at higher concentrations, resulting in bell-shaped curves for all steroids on the hydroxylase axis. Fluconazole was found to inhibit CYP17A1-lyase activity, causing suppression of androgens (IC50 = 114-209 µM) and estrogens (IC50 = 28 µM). The results indicate that these four azole drugs are highly potent in vitro and, based on plasma Cmax values, may exert endocrine disrupting effects at therapeutically relevant concentrations. This raises concern for endocrine related effects in patients using azole antifungal drugs, particularly when taken during sensitive periods like pregnancy.


Asunto(s)
Antifúngicos/toxicidad , Aromatasa/efectos de los fármacos , Clotrimazol/toxicidad , Disruptores Endocrinos/toxicidad , Fluconazol/toxicidad , Cetoconazol/toxicidad , Miconazol/toxicidad , Esteroide 17-alfa-Hidroxilasa/antagonistas & inhibidores , Inhibidores de la Aromatasa/toxicidad , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Cromatografía de Gases y Espectrometría de Masas , Humanos , Concentración 50 Inhibidora
10.
Malar J ; 17(1): 464, 2018 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-30537973

RESUMEN

BACKGROUND: Most epidemiological studies on the interplay between iron deficiency and malaria risk classify individuals as iron-deficient or iron-replete based on inflammation-dependent iron markers and adjustment for inflammation by using C-reactive protein (CRP) or α-1-acid glycoprotein (AGP). The validity of this approach and the usefulness of fibroblast growth factor 23 (FGF23) as a proposed inflammation-independent iron marker were tested. METHODS: Conventional iron markers and FGF23 were measured in children with acute falciparum malaria and after 1, 2, 4, and 6 weeks. Children, who were transfused or received iron supplementation in the follow-up period, were excluded, and iron stores were considered to be stable throughout. Ferritin levels 6 weeks after admission were used as a reference for admission iron status and compared with iron markers at different time points. RESULTS: There were long-term perturbations in iron markers during convalescence from acute malaria. None of the tested iron parameters, including FGF23, were independent of inflammation. CRP and AGP normalized faster than ferritin after malaria episodes. CONCLUSION: Malaria may bias epidemiological studies based on inflammation-dependent iron markers. Better markers of iron status during and after inflammation are needed in order to test strategies for iron supplementation in populations at risk of malaria.


Asunto(s)
Deficiencias de Hierro , Hierro/sangre , Malaria Falciparum , Biomarcadores/sangre , Niño , Preescolar , Estudios de Cohortes , Enfermedades Carenciales/sangre , Enfermedades Carenciales/etiología , Femenino , Ferritinas/sangre , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/sangre , Hepcidinas/sangre , Humanos , Lactante , Inflamación/sangre , Hierro/uso terapéutico , Malaria Falciparum/sangre , Malaria Falciparum/complicaciones , Malaria Falciparum/epidemiología , Malaria Falciparum/fisiopatología , Masculino
11.
Chemosphere ; 212: 1142-1154, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30286543

RESUMEN

The present study investigated the occurrence and removal of 10 steroid hormones (4 androgens, 3 progestagens and 3 estrogens) in two WSP systems, Mafisa and Mzumbe in Morogoro, Tanzania. All 10 steroid hormones were detected in the influent of both WSP systems in the dry as well as in the rainy season. The concentrations of steroids in influent wastewater ranged from 0.1 ng/L for 17-OH-pregnenolone to 445 ng/L for estrone and from below limit of detection for 17-OH-pregnenolone to 45 ng/L for estrone in effluent. During dry season, the overall mean ±â€¯standard deviation removal efficiency for the 10 steroids were 70 ±â€¯21% for Mzumbe WSP and 97 ±â€¯3% for Mafisa WSP. During the rainy season the overall mean removal efficiency for all the steroid hormones were 52 ±â€¯32% for Mzumbe WSP and 94 ±â€¯8% for Mafisa WSP. Risk was characterized by calculating the risk quotients (RQs) for fish and humans. 46% of the total RQs calculated were above one, indicating high risk. Low RQs were estimated for androgens and progestagens but the estrogen concentrations measured in the WSP systems and Morogoro River indicated a high risk for fish. However, estrogens appeared not to pose an appreciable risk to human health from water intake and fish consumption. The results indicated that WSP systems are quite effective in removing steroid hormones from wastewater. Thus, low technology systems such as WSP systems are suitable techniques in low income counties due to relatively low costs of building, operating and maintaining these systems.


Asunto(s)
Hormonas , Medición de Riesgo , Esteroides , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Andrógenos/análisis , Animales , Estrógenos/análisis , Peces , Hormonas/análisis , Hormonas/aislamiento & purificación , Humanos , Estanques , Progestinas/análisis , Estaciones del Año , Esteroides/análisis , Esteroides/aislamiento & purificación , Tanzanía , Eliminación de Residuos Líquidos/economía , Contaminantes Químicos del Agua/aislamiento & purificación
12.
Toxicol Lett ; 285: 139-147, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29289696

RESUMEN

Mild analgesics have been associated with antiandrogenic effects, but there are no such studies on dipyrone, despite its high prevalence of use in many countries. We examined the production of steroid hormones in human H295R cells after exposure to dipyrone and two metabolites, 4-Methylaminoantipyrine (MAA) and 4-Aminoantipyrine (AA), as well as fetal testicular testosterone production in rats following maternal dipyrone exposure. Androgen agonistic/antagonistic effects were examined in vitro for dipyrone and its metabolites in the Yeast Androgen Screen (YAS) assay and in vivo for dipyrone through the Hershberger assay. In vitro we tested dipyrone, MAA, and AA (0.1-1000 µM) while in vivo we used dipyrone (50, 100, 200 mg/kg/day). In the H295R assay, dipyrone, MAA and AA reduced the production of androgens and corticosteroids. Testosterone was reduced at concentrations 4-13 times higher than the maximum plasma concentrations reported in humans for MAA and AA. No effects were observed in the fetal testosterone production assay. In the YAS and Hershberger assays, no androgen agonistic/antagonistic activities were observed. These results indicate that dipyrone and its metabolites do not interact with the androgen receptor, but have the potential to inhibit steroidogenesis, however only at concentrations that are not relevant under normal medical use.


Asunto(s)
Analgésicos/toxicidad , Antagonistas de Receptores Androgénicos/toxicidad , Andrógenos/toxicidad , Dipirona/toxicidad , Disruptores Endocrinos/toxicidad , Analgésicos/sangre , Antagonistas de Receptores Androgénicos/sangre , Andrógenos/sangre , Animales , Bioensayo , Línea Celular Tumoral , Dipirona/sangre , Disruptores Endocrinos/sangre , Femenino , Humanos , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Ratas , Ratas Wistar , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Testículo/efectos de los fármacos , Testículo/embriología , Testículo/metabolismo , Testosterona/biosíntesis
13.
Toxicol In Vitro ; 47: 63-71, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29100959

RESUMEN

The aim of this study was to determine the steroidogenic endocrine disrupting effect of three widely used serotonin-noradrenaline reuptake inhibitors duloxetine, venlafaxine and tramadol, using two in vitro models, the H295R assay and a recombinant CYP17 enzyme assay. Steroid hormones were quantified using LC-MS/MS. Duloxetine showed endocrine disrupting effects at 5-20µM with CYP17 being the main target. Venlafaxine also affected the steroidogenesis, mainly by affecting the CYP17 lyase reaction, although at much higher concentrations i.e. 100µM. Tramadol only exerted minor effects on the steroidogenesis with the lowest observed effect at 314µM. Based on the H295R results, the inhibition of CYP17 by duloxetine and venlafaxine was investigated in a recombinant CYP17 assay with the use of the 4 major CYP17 substrates pregnenolone, progesterone, 17α-hydroxypregnenolone and 17α-hydroxyprogesterone. Both duloxetine and venlafaxine inhibited CYP17 enzyme activity, but duloxetine was most potent. IC50-values were in the range 5.3-21µM for duloxetine and 1318-2750µM for venlafaxine. Overall, results from the recombinant CYP17 assay confirmed the results from the H295R cell assay. Using testosterone as end point, the margin of safety (defined as NOAEL/Cmax) for duloxetine was 1.6 indicating that duloxetine may have endocrine disrupting effects. In contrast, venlafaxine and tramadol showed higher margins of safety (venlafaxine: 24; tramadol: 157) indicating a lower potential to disrupt the human steroidogenesis.


Asunto(s)
Corteza Suprarrenal/efectos de los fármacos , Familia 17 del Citocromo P450/antagonistas & inhibidores , Clorhidrato de Duloxetina/efectos adversos , Disruptores Endocrinos/efectos adversos , Inhibidores de Captación de Serotonina y Norepinefrina/efectos adversos , Tramadol/efectos adversos , Clorhidrato de Venlafaxina/efectos adversos , Corteza Suprarrenal/metabolismo , Corticoesteroides/biosíntesis , Corticoesteroides/química , Corticoesteroides/metabolismo , Analgésicos Opioides/efectos adversos , Antidepresivos/efectos adversos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Inhibidores Enzimáticos del Citocromo P-450/efectos adversos , Familia 17 del Citocromo P450/genética , Familia 17 del Citocromo P450/metabolismo , Humanos , Límite de Detección , Estructura Molecular , Nivel sin Efectos Adversos Observados , Concentración Osmolar , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Reproducibilidad de los Resultados
14.
Toxicol In Vitro ; 41: 1-11, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28179152

RESUMEN

Selective serotonin reuptake inhibitors (SSRIs) used as first line of treatment in major depressive disorder (MDD) are known to exert negative effects on the endocrine system and fertility. The aim of the present study was to investigate the possible endocrine disrupting effect of six SSRIs, fluoxetine, paroxetine, citalopram and its active enantiomer escitalopram, sertraline and fluvoxamine using the OECD standardized and validated human in vitro adrenocortical H295R cell assay. All the major steroids, including progestagens, corticosteroids, androgens and estrogens were analysed using a fully validated LC-MS/MS method. All 6 SSRIs were found to exert endocrine disrupting effects on steroid hormone synthesis at concentrations just around Cmax. Although the mechanisms of disruption were all different, they all resulted in decreased testosterone levels, some due to effects on CYP17, some earlier in the pathway. Furthermore, all SSRIs relatively increased the estrogen/androgen ratio, indicating stimulating effects on the aromatase. Our study demonstrates the potential of SSRIs to interfere with steroid production in the H295R cells around Cmax levels and indicates that these drugs should be investigated further to determine any hazards for the users.


Asunto(s)
Andrógenos/metabolismo , Antidepresivos/farmacología , Disruptores Endocrinos/farmacología , Estrógenos/metabolismo , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Esteroides/metabolismo , Aromatasa/metabolismo , Línea Celular , Citalopram/farmacología , Familia 21 del Citocromo P450/metabolismo , Fluoxetina/farmacología , Fluvoxamina/farmacología , Humanos , Paroxetina/farmacología , Sertralina/farmacología , Esteroide 17-alfa-Hidroxilasa/metabolismo
15.
Environ Int ; 96: 180-189, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27692342

RESUMEN

Per- and polyfluoroalkyl substances (PFASs) are emerging in the Arctic and accumulate in brain tissues of East Greenland (EG) polar bears. In vitro studies have shown that PFASs might possess endocrine disrupting abilities and therefore the present study was conducted to investigate potential PFAS induced alterations in brain steroid concentrations. The concentrations of eleven steroid hormones were determined in eight brain regions from ten EG polar bears. Pregnenolone (PRE), the dominant progestagen, was found in mean concentrations of 5-47ng/g (ww) depending on brain region. PRE showed significantly (p<0.01) higher concentrations in female compared to male bears. Dehydroepiandrosterone (DHEA) found in mean concentrations 0.67-4.58ng/g (ww) was the androgen found in highest concentrations. Among the estrogens estrone (E1) showed mean concentrations of 0.90-2.21ng/g (ww) and was the most abundant. Remaining steroid hormones were generally present in concentrations below 2ng/g (ww). Steroid levels in brain tissue could not be explained by steroid levels in plasma. There was however a trend towards increasing estrogen levels in plasma resulting in increasing levels of androgens in brain tissue. Correlative analyses showed positive associations between PFASs and 17α-hydroxypregnenolone (OH-PRE) (e.g. perflouroalkyl sulfonates (∑PFSA): p<0.01, r=0.39; perfluoroalkyl carboxylates (∑PFCA): p<0.01, r=0.61) and PFCA and testosterone (TS) (∑PFCA: p=0.03, r=0.30) across brain regions. Further when investigating correlative associations in specific brain regions significant positive correlations were found between ∑PFCA and several steroid hormones in the occipital lobe. Correlative positive associations between PFCAs and steroids were especially observed for PRE, progesterone (PRO), OH-PRE, DHEA, androstenedione (AN) and testosterone (TS) (all p≤0.01, r≥0.7). The results from the present study generally indicate that an increase in PFASs concentration seems to concur with an increase in steroid hormones of EG polar bears. It is, however, not possible to determine whether alterations in brain steroid concentrations arise from interference with de novo steroid synthesis or via disruption of peripheral steroidogenic tissues mainly in gonads and feedback mechanisms. Steroids are important for brain plasticity and gender specific behavior as well as postnatal development and sexually dimorph brain function. The present work indicates an urgent need for a better mechanistic understanding of how PFASs may affect the endocrine system of polar bears and potentially other mammal species.


Asunto(s)
Encéfalo/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Hormonas/metabolismo , Hidrocarburos Fluorados/toxicidad , Esteroides/metabolismo , Ursidae/metabolismo , Alcanosulfonatos , Animales , Regiones Árticas , Encéfalo/metabolismo , Química Encefálica/efectos de los fármacos , Ácidos Carboxílicos , Disruptores Endocrinos/análisis , Disruptores Endocrinos/metabolismo , Monitoreo del Ambiente , Contaminantes Ambientales/efectos adversos , Contaminantes Ambientales/análisis , Contaminantes Ambientales/metabolismo , Femenino , Groenlandia , Hidrocarburos Fluorados/análisis , Hidrocarburos Fluorados/metabolismo , Masculino
16.
Sci Rep ; 6: 29468, 2016 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-27406023

RESUMEN

Cytochrome P450 17A1 (CYP17A1) is an important target in the treatment of prostate cancer because it produces androgens required for tumour growth. The FDA has approved only one CYP17A1 inhibitor, abiraterone, which contains a steroidal scaffold similar to the endogenous CYP17A1 substrates. Abiraterone is structurally similar to the substrates of other cytochrome P450 enzymes involved in steroidogenesis, and interference can pose a liability in terms of side effects. Using non-steroidal scaffolds is expected to enable the design of compounds that interact more selectively with CYP17A1. Therefore, we combined a structure-based virtual screening approach with density functional theory (DFT) calculations to suggest non-steroidal compounds selective for CYP17A1. In vitro assays demonstrated that two such compounds selectively inhibited CYP17A1 17α-hydroxylase and 17,20-lyase activities with IC50 values in the nanomolar range, without affinity for the major drug-metabolizing CYP2D6 and CYP3A4 enzymes and CYP21A2, with the latter result confirmed in human H295R cells.


Asunto(s)
Diseño de Fármacos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Esteroide 17-alfa-Hidroxilasa/antagonistas & inhibidores , Androstenos/farmacología , Dominio Catalítico , Línea Celular Tumoral , Supervivencia Celular , Cromatografía Liquida , Cristalografía por Rayos X , Humanos , Concentración 50 Inhibidora , Ligandos , Masculino , Espectrometría de Masas , Simulación del Acoplamiento Molecular , Nitrógeno/química , Próstata/metabolismo , Unión Proteica , Esteroide 17-alfa-Hidroxilasa/sangre , Esteroide 17-alfa-Hidroxilasa/metabolismo , Esteroides
17.
Anal Bioanal Chem ; 408(18): 4883-95, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27150205

RESUMEN

Measuring both progestagens, androgens, corticosteroids as well as estrogens with a single method makes it possible to investigate the effects of endocrine-disrupting chemicals (EDCs) on the main pathways in the mammalian steroidogenesis. This paper presents two simple methods for the determination of the major steroid hormones in biological matrixes using liquid chromatography tandem mass spectrometry (LC-MS(2)). A novel method was developed for the determination of 14 steroids in the H295R in vitro assay without the need for solid phase extraction (SPE) purification prior to LC-MS(2) analysis. The in vitro assay was validated by exposing H295R cells to prochloraz for inhibiting steroid hormone secretion and by exposing cells to forskolin for inducing steroid hormone secretion. The developed method fulfills the recommendations for the H295R assay suggested by the OECD. Furthermore, a simple off-line SPE methodology was developed for the necessary clean-up of in vivo assays. Samples, such as gonad tissue, plasma and serum, are complex biological matrixes, and the SPE methodology was optimized to remove salts and proteins prior to elution of target analytes. At the same time, lipophilic compounds were retained on the SPE cartridge during elution. This, combined with the multi-steroid LC-MS(2) method, made it possible to determine 10 steroids in male Sprague-Dawley rat gonad tissue. Furthermore, it was possible to quantify 6 steroids in the plasma. In general, the observed concentration of steroid hormones in plasma, testes, and H295R cell medium corresponded well with previous studies. The off-line SPE method was validated using spiked charcoal-stripped serum. Method recovery, accuracy, precision and robustness were all good. Instrument sensitivity was in the range of 55-530 pg/mL (LLOQ).


Asunto(s)
Bioensayo/métodos , Cromatografía Liquida/métodos , Disruptores Endocrinos/administración & dosificación , Hormonas Esteroides Gonadales/metabolismo , Espectrometría de Masas/métodos , Manejo de Especímenes/métodos , Testículo/metabolismo , Animales , Línea Celular Tumoral , Hormonas Esteroides Gonadales/sangre , Humanos , Técnicas In Vitro , Masculino , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Testículo/efectos de los fármacos
18.
Reprod Toxicol ; 58: 174-83, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26476359

RESUMEN

Endocrine modulating effects of Simvastatin (SV) and its metabolite, Simvastatin ß-hydroxy acid (SVA), were investigated in H295R cells and in female Sprague-Dawley (SPRD) rats. H295R cells were exposed to SV and SVA concentrations from 0 to 10µM for 48h. Four groups of SPRD rats received 0 (CT), 1.3 (L), 5.0 (M), and 20.0 (H)mg SV/kg bw/day for 14 days. 10 Steroids were investigated in H295R growth media, and in tissues and plasma from rats using GC-MS/MS. Plasma LH and FSH were quantified by ELISA. In the H295R assay, SV and SVA particularly decreased progestagens with IC50-values from 0.10-0.13µM for SV and from 0.019-0.055µM for SVA. In rats, SV decreased progestagens in ovaries, brain and plasma, and plasma FSH in the M (72.4% decrease) and H group (76.6% decrease). Because progestagens and gonadotropins are major players in fertility, administration of SV might exert negative effects on female reproduction.


Asunto(s)
Corteza Suprarrenal/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Hormona Folículo Estimulante/biosíntesis , Hormonas Esteroides Gonadales/biosíntesis , Inhibidores de Hidroximetilglutaril-CoA Reductasas/toxicidad , Simvastatina/toxicidad , Corteza Suprarrenal/metabolismo , Animales , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Femenino , Fertilidad/efectos de los fármacos , Hormona Folículo Estimulante/sangre , Cromatografía de Gases y Espectrometría de Masas , Hormonas Esteroides Gonadales/sangre , Hormona Luteinizante/biosíntesis , Hormona Luteinizante/sangre , Ratas Sprague-Dawley , Reproducción/efectos de los fármacos , Medición de Riesgo , Espectrometría de Masas en Tándem , Factores de Tiempo
19.
Aquat Toxicol ; 168: 28-37, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26432166

RESUMEN

A 27-day controlled exposure study of adult male African clawed frogs (Xenopus laevis) was conducted to examine the mechanism by which tebuconazole may disrupt steroidogenesis. The fungicide was measured by LC-MS/MS in tank water and in target tissues (adipose, kidney, liver, and brain), and we observed tissue-specific bioconcentration with BCF up to 238. Up to 10 different steroid hormones were quantified in gonads using LC-MS/MS and in plasma using GC-MS/MS and a radioimmunoassay was performed for further measurement of androgens. In order to assess whether effects increased with exposure or animals adapted to the xenobiotic, blood samples were collected 12 days into the study and at termination (day 27). After 12 days of exposure to 100 and 500µgL(-1) tebuconazole, plasma levels of testosterone (T) and dihydrotestosterone (DHT) were increased, while plasma 17ß-estradiol (E2) concentrations were greatly reduced. Exposure to 0.1µgL(-1), on the other hand, resulted in decreased levels of T and DHT, with no effects observed for E2. After 27 days of exposure, effects were no longer observed in circulating androgen levels while the suppressive effect on E2 persisted in the two high-exposure groups (100 and 500µgL(-1)). Furthermore, tebuconazole increased gonadal concentrations of T and DHT as well as expression of the enzyme CYP17 (500µgL(-1), 27 days). These results suggest that tebuconazole exposure may supress the action of CYP17 at the lowest exposure (0.1µgL(-1)), while CYP19 suppression dominates at higher exposure concentrations (increased androgens and decreased E2). Increased androgen levels in plasma half-way into the study and in gonads at termination may thus be explained by compensatory mechanisms, mediated through increased enzymatic expression, as prolonged exposure had no effect on circulating androgen levels.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Triazoles/toxicidad , Xenopus laevis/fisiología , Andrógenos/metabolismo , Animales , Aromatasa/genética , Aromatasa/metabolismo , Dihidrotestosterona/metabolismo , Estradiol/sangre , Estradiol/genética , Estradiol/metabolismo , Fungicidas Industriales/toxicidad , Gónadas/química , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Masculino , Esteroide 17-alfa-Hidroxilasa/genética , Esteroide 17-alfa-Hidroxilasa/metabolismo , Espectrometría de Masas en Tándem , Testosterona/metabolismo , Contaminantes Químicos del Agua/toxicidad
20.
Toxicol Sci ; 148(1): 288-98, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26259604

RESUMEN

Industrial use of aniline is increasing worldwide with production estimated to surpass 5.6 million metric tons in 2016. Exposure to aniline occurs via air, diet, and water augmenting the risk of exposing a large number of individuals. Early observations suggest that aniline is metabolized to paracetamol/acetaminophen, likely explaining the omnipresence of low concentrations of paracetamol in European populations. This is of concern as recent studies implicate paracetamol as a disrupter of reproduction. Here, we show through steroidogenic profiling that exposure to aniline led to increased levels of the Δ4 steroids, suggesting that the activity of CYP21 was decreased. By contrast, paracetamol decreased levels of androgens likely through inhibition of CYP17A1 activity. We confirm that aniline in vivo is rapidly converted to paracetamol by the liver. Intrauterine exposure to aniline and paracetamol in environmental and pharmaceutical relevant doses resulted in shortening of the anogenital distance in mice, a sensitive marker of fetal androgen levels that in humans is associated with reproductive malformations and later life reproductive disorders. In conclusion, our results provide evidence for a scenario where aniline, through its conversion into antiandrogenic paracetamol, impairs male reproductive development.


Asunto(s)
Acetaminofén/toxicidad , Compuestos de Anilina/toxicidad , Carcinógenos Ambientales/toxicidad , Disruptores Endocrinos/toxicidad , Infertilidad Masculina/inducido químicamente , Acetaminofén/metabolismo , Compuestos de Anilina/metabolismo , Animales , Biotransformación , Carcinógenos Ambientales/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Disruptores Endocrinos/metabolismo , Femenino , Desarrollo Fetal/efectos de los fármacos , Humanos , Técnicas In Vitro , Infertilidad Masculina/metabolismo , Infertilidad Masculina/patología , Hígado/enzimología , Hígado/metabolismo , Masculino , Intercambio Materno-Fetal , Ratones Endogámicos C57BL , Embarazo , Progesterona/agonistas , Progesterona/metabolismo , Desarrollo Sexual/efectos de los fármacos , Testosterona/antagonistas & inhibidores , Testosterona/metabolismo , Toxicocinética
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