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1.
Drug Metab Dispos ; 42(9): 1556-66, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25002748

RESUMO

Several factors are thought to be implicated in the occurrence of idiosyncratic adverse drug reactions. The present work aimed to question as to whether inflammation is a determinant factor in hepatic lesions induced by chlorpromazine (CPZ) using the human HepaRG cell line. An inflammation state was induced by a 24-hour exposure to proinflammatory cytokines interleukin-6 (IL-6) and IL-1ß; then the cells were simultaneously treated with CPZ and/or cytokine for 24 hours or daily for 5 days. The inflammatory response was assessed by induction of C-reactive protein and IL-8 transcripts and proteins as well as inhibition of CPZ metabolism and down-regulation of cytochrome 3A4 (CYP3A4) and CYP1A2 transcripts, two major cytochrome P450 (P450) enzymes involved in its metabolism. Most effects of cotreatments with cytokines and CPZ were amplified or only observed after five daily treatments; they mainly included increased cytotoxicity and overexpression of oxidative stress-related genes, decreased Na(+)-taurocholate cotransporting polypeptide mRNA levels and activity, a key transporter involved in bile acids uptake, and deregulation of several other transporters. However, CPZ-induced inhibition of taurocholic acid efflux and pericanalicular F-actin distribution were not affected. In addition, a time-dependent induction of phospholipidosis was noticed in CPZ-treated cells, without obvious influence of the inflammatory stress. In summary, our results show that an inflammatory state induced by proinflammatory cytokines increased cytotoxicity and enhanced some cholestatic features induced by the idiosyncratic drug CPZ in HepaRG cells. These changes, together with inhibition of P450 activities, could have important consequences if extrapolated to the in vivo situation.


Assuntos
Clorpromazina/efeitos adversos , Colestase/metabolismo , Inflamação/metabolismo , Actinas/genética , Actinas/metabolismo , Ácidos e Sais Biliares/genética , Ácidos e Sais Biliares/metabolismo , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Linhagem Celular , Colestase/induzido quimicamente , Colestase/genética , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Regulação para Baixo/genética , Humanos , Inflamação/genética , Interleucinas/genética , Interleucinas/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Estresse Oxidativo/genética , RNA Mensageiro/genética , Simportadores/genética , Simportadores/metabolismo , Ácido Taurocólico/genética , Ácido Taurocólico/metabolismo
2.
Mol Cell Biochem ; 378(1-2): 205-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23494528

RESUMO

Natural polyamines such as putrescine (Put), spermidine (Spd), and spermine (Spm), which are present in the human diet in large amounts, associated with their active transporter, are assumed to play a role in non-heme iron uptake and iron bioavailability from nutrients. Enterocytes and hepatocytes play pivotal roles in the regulation of body iron homeostasis. In this study, we report the effects of natural polyamines on iron transport in the Caco-2 cell line. In enterocyte-like Caco-2 cells, polyamines did not significantly modulate the transepithelial iron flux across the cell monolayer cultured on permeable membranes. In contrast, Spd, Spm, and to a lesser extent, Put were shown to activate Caco-2 cell iron uptake and to induce an increase in the ferritin level. This iron co-transport in enterocytes, which involved an interaction between iron and polyamine then cell uptake of the polyamine-iron complexes by the polyamine transport system, was more pronounced in proliferating than in differentiated Caco-2 cells. Moreover, it was observed at physiological concentrations of both polyamines and iron. It could thus play a role in the rapid renewal of enterocytes. These data suggest the involvement of polyamines as components of the pool of transferrin-independent iron-chelating vectors. Further investigations are needed to demonstrate their biological relevance in physiological situations.


Assuntos
Compostos Férricos/metabolismo , Poliaminas/farmacologia , Transporte Biológico , Células CACO-2 , Diferenciação Celular , Permeabilidade da Membrana Celular , Proliferação de Células , Ferritinas/metabolismo , Humanos
3.
Lab Invest ; 92(3): 396-410, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22157718

RESUMO

Although carbon tetrachloride (CCl(4))-induced acute and chronic hepatotoxicity have been extensively studied, little is known about the very early in vivo effects of this organic solvent on oxidative stress and mitochondrial function. In this study, mice were treated with CCl(4) (1.5 ml/kg ie 2.38 g/kg) and parameters related to liver damage, lipid peroxidation, stress/defense and mitochondria were studied 3 h later. Some CCl(4)-intoxicated mice were also pretreated with the cytochrome P450 2E1 inhibitor diethyldithiocarbamate or the antioxidants Trolox C and dehydroepiandrosterone. CCl(4) induced a moderate elevation of aminotransferases, swelling of centrilobular hepatocytes, lipid peroxidation, reduction of cytochrome P4502E1 mRNA levels and a massive increase in mRNA expression of heme oxygenase-1 and heat shock protein 70. Moreover, CCl(4) intoxication induced a severe decrease of mitochondrial respiratory chain complex IV activity, mitochondrial DNA depletion and damage as well as ultrastructural alterations. Whereas DDTC totally or partially prevented all these hepatic toxic events, both antioxidants protected only against liver lipid peroxidation and mitochondrial damage. Taken together, our results suggest that lipid peroxidation is primarily implicated in CCl(4)-induced early mitochondrial injury. However, lipid peroxidation-independent mechanisms seem to be involved in CCl(4)-induced early hepatocyte swelling and changes in expression of stress/defense-related genes. Antioxidant therapy may not be an efficient strategy to block early liver damage after CCl(4) intoxication.


Assuntos
Intoxicação por Tetracloreto de Carbono/metabolismo , Hepatócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Animais , Antioxidantes/farmacologia , Tetracloreto de Carbono , Cromanos/farmacologia , Inibidores do Citocromo P-450 CYP2E1 , Desidroepiandrosterona/farmacologia , Ditiocarb/farmacologia , Masculino , Camundongos , Mitocôndrias Hepáticas/efeitos dos fármacos
4.
J Pharmacol Exp Ther ; 342(3): 676-87, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22647274

RESUMO

Clinical investigations suggest that hepatotoxicity after acetaminophen (APAP) overdose could be more severe in the context of obesity and nonalcoholic fatty liver disease. The pre-existence of fat accumulation and CYP2E1 induction could be major mechanisms accounting for such hepatic susceptibility. To explore this issue, experiments were performed in obese diabetic ob/ob and db/db mice. Preliminary investigations performed in male and female wild-type, ob/ob, and db/db mice showed a selective increase in hepatic CYP2E1 activity in female db/db mice. However, liver triglycerides in these animals were significantly lower compared with ob/ob mice. Next, APAP (500 mg/kg) was administered in female wild-type, ob/ob, and db/db mice, and investigations were carried out 0.5, 2, 4, and 8 h after APAP intoxication. Liver injury 8 h after APAP intoxication was higher in db/db mice, as assessed by plasma transaminases, liver histology, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. In db/db mice, however, the extent of hepatic glutathione depletion, levels of APAP-protein adducts, c-Jun N-terminal kinase activation, changes in gene expression, and mitochondrial DNA levels were not greater compared with the other genotypes. Furthermore, in the db/db genotype plasma lactate and ß-hydroxybutyrate were not specifically altered, whereas the plasma levels of APAP-glucuronide were intermediary between wild-type and ob/ob mice. Thus, early APAP-induced hepatotoxicity was greater in db/db than ob/ob mice, despite less severe fatty liver and similar basal levels of transaminases. Hepatic CYP2E1 induction could have an important pathogenic role when APAP-induced liver injury occurs in the context of obesity and related metabolic disorders.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fígado/efeitos dos fármacos , Obesidade/metabolismo , Ácido 3-Hidroxibutírico/sangue , Acetaminofen/sangue , Animais , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocromo P-450 CYP2E1/metabolismo , DNA Mitocondrial/metabolismo , Fígado Gorduroso/sangue , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Feminino , Glucuronídeos/sangue , Glutationa/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Ácido Láctico/sangue , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Obesidade/sangue , Obesidade/patologia , Sulfatos/sangue , Triglicerídeos/sangue
5.
Facts Views Vis Obgyn ; 9(2): 101-104, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29209486

RESUMO

OBJECTIVE: The purpose of this pilot study is to compare the 2D scanning measurement of the foetal femoral diaphysis using anterior or lateral/external incidence at ultrasound. METHODS: In August 2016, 30 consecutive patients underwent a second trimester morphology ultrasound between 21 and 24 weeks of gestation by a senior sonographist. In each case, the femur length was measured either with an anterior angle, estimating the straight aspect of the diaphysis or with a lateral angle, assessing its curved aspect. The two measures were collected prospectively. The difference between paired measurements was calculated and expressed in percentage (mm) and in percentile. RESULTS: The median difference between the two ultrasound angles in terms of femur length was 3,55% and in terms of percentile variation was 17,16. CONCLUSION: An anterior angle of measurement of the femur length seems to allow an optimal measure of the straight and longest aspect of the diaphysis. According to our results, this angle should be considered when scoring the quality of a morphological ultrasound, but further and larger studies should be done to confirm our hypothesis.

6.
Forensic Sci Int ; 266: e38-e42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27342343

RESUMO

Powdered roots of iboga (Tabernanthe iboga) contain ibogaine, an alkaloid that has been used to treat addictions. We report the case of a 30-year-old woman who died after ingesting a powder labeled as Tabernanthe iboga she had bought online. Analysis of the powder revealed the absence of ibogaine but the presence of toxic alkaloids (ajmaline, yohimbine and reserpine) found in Rauvolfia sp. plant species. An original and specific LC-MS/MS method developed to quantify ajmaline, yohimbine and reserpine showed respective concentrations of 109.1ng/mL, 98.2ng/mL and 30.8ng/mL in blood, and 1528.2ng/mL, 914.2ng/mL and 561.2ng/mL in bile. Moreover, systematic toxicological analyses of biological samples showed the presence of oxazepam at therapeutic concentration and cannabinoids. Death could be attributed to ingestion of a substantial quantity of crushed roots of Rauvolfia in association with concomitant drug withdrawal.


Assuntos
Rotulagem de Produtos , Rauwolfia/intoxicação , Alcaloides de Triptamina e Secologanina/intoxicação , Adulto , Cromatografia Líquida , Feminino , Toxicologia Forense , Humanos , Pós , Alcaloides de Triptamina e Secologanina/isolamento & purificação , Espectrometria de Massas em Tandem
7.
Biochem Pharmacol ; 96(3): 179-89, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26070250

RESUMO

Tumor cell growth requires large iron quantities and the deprivation of this metal induced by synthetic metal chelators is therefore an attractive method for limiting the cancer cell proliferation. The antiproliferative effect of the Quilamine HQ1-44, a new iron chelator vectorized toward tumor cells by a polyamine chain, is related to its high selectivity for the Polyamine Transport System (PTS), allowing its preferential uptake by tumoral cells. The difference in PTS activation between healthy cells and tumor cells enables tumor cells to be targeted, whereas the strong dependence of these cells on iron ensures a secondary targeting. Here, we demonstrated in vitro that HQ1-44 inhibits DNA synthesis and cell proliferation of HCT116 cells by modulating the intracellular metabolism of both iron and polyamines. Moreover, in vivo, in xenografted athymic nude mice, we found that HQ1-44 was as effective as cis-platin in reducing HCT116 tumor growth, without its side effects. Furthermore, as suggested by in vitro data, the depletion in exogenous or endogenous polyamines, known to activate the PTS, dramatically enhanced the antitumor efficiency of HQ1-44. These data support the need for further studies to assess the value of HQ1-44 as an adjuvant treatment in cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , DNA de Neoplasias/antagonistas & inibidores , Eflornitina/farmacologia , Quelantes de Ferro/farmacologia , Poliaminas/antagonistas & inibidores , Animais , Transporte Biológico/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , DNA de Neoplasias/biossíntese , Feminino , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Terapia de Alvo Molecular , Transplante de Neoplasias , Poliaminas/metabolismo , Transplante Heterólogo , Carga Tumoral/efeitos dos fármacos
8.
Redox Rep ; 8(2): 95-104, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12804012

RESUMO

This study was designed to evaluate the effect of high concentrations of melatonin on the peroxidation of human low density lipoproteins (LDLs) initiated by O(2)(*-) and ethanol-derived peroxyl radicals (RO(2)(*)) from water gamma radiolysis in the presence of ethanol. LDL (3 g/l; total LDL concentration) was oxidized in the absence of melatonin or in its presence at three concentrations (50 x 10(-6), 100 x 10(-6) or 250 x 10(-6) mol/l) in ethanol. Radiolytic yields (i.e. number of mole consumed or produced per Joule) of the markers of lipid peroxidation were determined (i.e. decrease in the endogenous antioxidants alpha-tocopherol and beta-carotene, formation of conjugated dienes and of thiobarbituric acid-reactive substances [TBARS]). Melatonin decreased the yields of lipid peroxidation products and delayed the onset of the propagation phase for conjugated dienes and TBARS in a concentration-dependent manner. Nevertheless, melatonin did not protect endogenous alpha-tocopherol against peroxyl-induced oxidation (probably due to a lower scavenging capacity than that of alpha-tocopherol towards peroxyl radicals), but delayed the consumption of LDL endogenous beta-carotene and decreased its rate of disappearance. The effect of melatonin seemed to be the highest for a melatonin concentration of 250 x 10(-6) mol/l.


Assuntos
Lipoproteínas LDL/metabolismo , Melatonina/metabolismo , Oxigênio/metabolismo , beta Caroteno/metabolismo , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Etanol/farmacologia , Radicais Livres , Raios gama , Humanos , Peroxidação de Lipídeos , Modelos Químicos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , alfa-Tocoferol/metabolismo
9.
J Anal Toxicol ; 38(6): 335-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24778089

RESUMO

Mycotoxin intoxications can result from the consumption of amatoxins like α- and ß-amanitin or of phallotoxin, present in several toxic mushrooms like Amanita phalloides. To identify and quantify amatoxins and phallotoidin in biological matrixes, we developed a method using liquid chromatography coupled with an ultra-high-resolution and accurate mass instrument (liquid chromatography-high-resolution-mass spectrometry, LC-HR-MS), Q Exactive™ (Thermo Fisher). The method includes a simple solid-phase extraction of urine samples spiked with flurazepam as internal standard (IS), using Bond Elut Agilent Certify cartridges (C18, 200 mg, 3 mL). LC separation was performed on a C18 Accucore column (100 × 2.1 mm, 2.6 µm) using a gradient of 10 mM ammonium acetate buffer containing 0.1% (v/v) formic acid and of acetonitrile with 0.1% (v/v) formic acid. Separation of analytes was obtained in 7 min, with respective retention times for α-amanitin, ß-amanitin, phalloidin and IS of 1.9, 1.7, 3.5 and 3.8 min, respectively. Quantitation on the LC-HR-MS system was performed by extracting the exact mass value of each protonated species using a 5-p.p.m. mass window, which was 919.3614, 920.3455, 789.3257 and 388.1586 for α-amanitin, ß-amanitin, phalloidin and IS, respectively. Calibration curves were obtained by spiking drug-free urine at 1-100 ng/mL. Mean correlation coefficients, r(2), were above 0.99 for each amatoxins and phalloidin. According to currently accepted validation procedures, the method was tested for selectivity, calibration, accuracy, matrix effect, precision and recovery. Authentic urine samples from 43 patients suffering from a suspected intoxication with mushrooms were analyzed by LC-HR-MS, and the results were compared with ELISA competitive immunoassay. The LC-HR-MS presented large benefits over immunoassay of being specific, faster and more sensitive, making it suitable for daily emergency toxicological analysis.


Assuntos
Alfa-Amanitina/urina , Intoxicação Alimentar por Cogumelos/urina , Faloidina/urina , Amanitinas/urina , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas por Ionização por Electrospray/métodos
10.
J Anal Toxicol ; 37(2): 110-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23316031

RESUMO

A fast and sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) method was developed and validated for the simultaneous determination of acetaminophen (APAP) and its glucuronide and sulfate metabolites (APAP-GLU and APAP-SUL) in small plasma volumes. This method included a simple step of sample preparation and a chromatographic separation on an LC-MS-MS system equipped with an electrospray ionization source and a tandem triple quadrupole mass spectrometer in multiple reaction monitoring mode. The analytes and internal standard, APAP deuterated analog, were separated on a C18 column (3.0 µm, 2.1 × 100 mm), using aqueous 1% formic acid and methanol (80:20, v/v) as the mobile phase. The LC-MS-MS method was validated for accuracy, precision, linearity, extraction efficiency, process efficiency and matrix effect. Calibration curves were obtained by fortifying drug-free plasma and ranges of linearity were set between 0.25-20 mg/L. The mean correlation coefficients, r², were >0.99 for APAP and its metabolites. The inter-day and intra-day precision values were less than 11.75 and 13.03%, respectively, at the lower limit of quantification concentration. The usability of the method was demonstrated by studying APAP metabolism in C57BL/6J wild-type and obese ob/ob female mice, in which only small plasma volumes were available. The results showed that APAP glucuronidation was enhanced in obese mice, suggesting that changes in APAP metabolism could modify its toxicity in obesity and related fatty liver disease.


Assuntos
Acetaminofen/sangue , Analgésicos não Narcóticos/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Acetaminofen/farmacocinética , Analgésicos não Narcóticos/farmacocinética , Animais , Calibragem , Cromatografia Líquida de Alta Pressão , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/metabolismo , Feminino , Glucuronídeos/análise , Glucuronídeos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Reprodutibilidade dos Testes , Sulfatos/análise , Sulfatos/metabolismo
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