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1.
Pharmacol Res ; 131: 211-217, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29452290

RESUMO

Severely obese patients undergoing bariatric surgery (BS) are at increased risk for venous thromboembolism (VTE). How standard low molecular weight heparin (LMWH) regimen should be adapted to provide both sufficient efficacy and safety in this setting is unclear. We aimed to compare the influence of four body size descriptors (BSD) on peak anti-Xa levels in BS obese patients receiving LMWH fixed doses to identify which one had the greatest impact. One hundred and thirteen BS obese patients [median body mass index (BMI), 43.3 kg/m2 (IQR, 40.6-48.7 kg/m2)] receiving subcutaneous dalteparin 5000 IU twice daily were included in this prospective monocenter study. Peak steady-state anti-Xa levels were measured peri-operatively following thromboprophylaxis initiation. Only 48% of patients achieved target anti-Xa levels (0.2-0.5 IU/ml). In univariate analysis, age, gender, total body-weight (TBW), lean body-weight (LBW), ideal body-weight (IBW), BMI and estimated glomerural filtration rate (eGFR) were associated with anti-Xa levels. The strongest negative association was observed with LBW (r = -0.56, p < .0001). Receiver operating characteristic curves indicated that among BSD, LBW (cut-off >55.8 kg) had the highest sensitivity (73%) and specificity (69%) to predict sub-prophylactic anti-Xa levels. In multivariate analysis, LBW and eGFR remained associated with anti-Xa levels (ß = -0.47 ±â€¯0.08, p < .0001 and ß = -0.19 ±â€¯0.08; p = .02, respectively). In BS morbidly obese patients receiving LMWH for thromboprophylaxis after BS, LBW and eGFR are the main determinants of anti-Xa level, and could be proposed in LMWH-based thromboprophylaxis dosing algorithms. The efficacy of a LBW-scale based dosing algorithm for optimal VTE prevention deserves further prospective randomized trials.


Assuntos
Anticoagulantes/uso terapêutico , Dalteparina/uso terapêutico , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Adulto , Cirurgia Bariátrica , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Peso Corporal Ideal , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Redução de Peso
2.
Toxicol Sci ; 158(2): 367-378, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28541575

RESUMO

Derisking xenobiotic-induced nongenotoxic carcinogenesis (NGC) represents a significant challenge during the safety assessment of chemicals and therapeutic drugs. The identification of robust mechanism-based NGC biomarkers has the potential to enhance cancer hazard identification. We previously demonstrated Constitutive Androstane Receptor (CAR) and WNT signaling-dependent up-regulation of the pluripotency associated Dlk1-Dio3 imprinted gene cluster noncoding RNAs (ncRNAs) in the liver of mice treated with tumor-promoting doses of phenobarbital (PB). Here, we have compared phenotypic, transcriptional ,and proteomic data from wild-type, CAR/PXR double knock-out and CAR/PXR double humanized mice treated with either PB or chlordane, and show that hepatic Dlk1-Dio3 locus long ncRNAs are upregulated in a CAR/PXR-dependent manner by two structurally distinct CAR activators. We further explored the specificity of Dlk1-Dio3 locus ncRNAs as hepatic NGC biomarkers in mice treated with additional compounds working through distinct NGC modes of action. We propose that up-regulation of Dlk1-Dio3 cluster ncRNAs can serve as an early biomarker for CAR activator-induced nongenotoxic hepatocarcinogenesis and thus may contribute to mechanism-based assessments of carcinogenicity risk for chemicals and novel therapeutics.


Assuntos
Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Iodeto Peroxidase/genética , Fígado/efeitos dos fármacos , RNA Longo não Codificante/genética , Receptores Citoplasmáticos e Nucleares/agonistas , Xenobióticos/toxicidade , Animais , Biomarcadores/metabolismo , Proteínas de Ligação ao Cálcio , Clordano/toxicidade , Receptor Constitutivo de Androstano , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Knockout , Fenobarbital/toxicidade , Regulação para Cima/efeitos dos fármacos
3.
Proc Natl Acad Sci U S A ; 114(12): 3151-3156, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28265066

RESUMO

Inhibitors of double minute 2 protein (MDM2)-tumor protein 53 (TP53) interaction are predicted to be effective in tumors in which the TP53 gene is wild type, by preventing TP53 protein degradation. One such setting is represented by the frequent CDKN2A deletion in human cancer that, through inactivation of p14ARF, activates MDM2 protein, which in turn degrades TP53 tumor suppressor. Here we used piggyBac (PB) transposon insertional mutagenesis to anticipate resistance mechanisms occurring during treatment with the MDM2-TP53 inhibitor HDM201. Constitutive PB mutagenesis in Arf-/- mice provided a collection of spontaneous tumors with characterized insertional genetic landscapes. Tumors were allografted in large cohorts of mice to assess the pharmacologic effects of HDM201. Sixteen out of 21 allograft models were sensitive to HDM201 but ultimately relapsed under treatment. A comparison of tumors with acquired resistance to HDM201 and untreated tumors identified 87 genes that were differentially and significantly targeted by the PB transposon. Resistant tumors displayed a complex clonality pattern suggesting the emergence of several resistant subclones. Among the most frequent alterations conferring resistance, we observed somatic and insertional loss-of-function mutations in transformation-related protein 53 (Trp53) in 54% of tumors and transposon-mediated gain-of-function alterations in B-cell lymphoma-extra large (Bcl-xL), Mdm4, and two TP53 family members, resulting in expression of the TP53 dominant negative truncations ΔNTrp63 and ΔNTrp73. Enhanced BCL-xL and MDM4 protein expression was confirmed in resistant tumors, as well as in HDM201-resistant patient-derived tumor xenografts. Interestingly, concomitant inhibition of MDM2 and BCL-xL demonstrated significant synergy in p53 wild-type cell lines in vitro. Collectively, our findings identify several potential mechanisms by which TP53 wild-type tumors may escape MDM2-targeted therapy.


Assuntos
Elementos de DNA Transponíveis , Resistencia a Medicamentos Antineoplásicos/genética , Vetores Genéticos/genética , Mutagênese Insercional , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética , Aloenxertos , Animais , Antineoplásicos/farmacologia , Biomarcadores Tumorais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Deriva Genética , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Knockout , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/mortalidade , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
4.
Surg Obes Relat Dis ; 13(2): 320-326, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27720420

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a leading cause of death in obese patients undergoing bariatric surgery (BS), but there is neither consensus nor high-level guidelines yet on VTE prophylaxis in this specific population. OBJECTIVE: We aimed to evaluate patterns of BS perioperative thromboprophylaxis practices. SETTING: French obesity specialized care centers (CSO), which are tertiary care referral hospitals for the most severe cases of obesity METHODS: A detailed questionnaire survey (11 opened, 15 closed questions) investigating their prophylactic schemes of anticoagulation (molecule, dose, weight-adjustment, duration, associated measures, follow-up) was sent to the 37 CSO. RESULTS: Completion rate was 92%. Over 90% of respondents indicated using low molecular weight heparin. Enoxaparin was the most commonly used molecule (89%), twice daily (71%), started mostly 6 hours after BS (74%), whereas fondaparinux (9%), dalteparin (6%), and tinzaparin (6%) were less often prescribed. Dosing varied significantly according to centers from 4000 to 12,000 IU/d, with the most commonly used dose being 8000 IU once daily, 83%, as well as treatment duration (1 week, 9%; 3 weeks, 47%). Half CSO adjusted low molecular weight heparin dose to weight. Biological monitoring was performed in 88%. Only 1 center followed systematically anti-Xa activity. Associated measures such as elastic stoking or intermittent pneumatic compression were used in 32% and 26%, respectively, and both were used in 39%. CONCLUSION: This study finds significant discrepancies in thromboprophylaxis practices in obese patients undergoing BS, particularly with respect to treatment duration and dose adjustment, highlighting the urgent need for improved implementation of existing clinical practice guidelines in this VTE high-risk population.


Assuntos
Cirurgia Bariátrica/métodos , Obesidade Mórbida/cirurgia , Tromboembolia Venosa/prevenção & controle , Idoso , Anticoagulantes/administração & dosagem , Estudos Transversais , Esquema de Medicação , Feminino , França , Humanos , Dispositivos de Compressão Pneumática Intermitente/estatística & dados numéricos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Hemorragia Pós-Operatória/etiologia , Padrões de Prática Médica/estatística & dados numéricos , Autorrelato , Meias de Compressão/estatística & dados numéricos , Centros de Atenção Terciária/estatística & dados numéricos , Trombose Venosa/etiologia
5.
Sci Rep ; 6: 36923, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27853279

RESUMO

Antibodies targeting IL-17A or its receptor IL-17RA show unprecedented efficacy in the treatment of autoimmune diseases such as psoriasis. These therapies, by neutralizing critical mediators of immunity, may increase susceptibility to infections. Here, we compared the effect of antibodies neutralizing IL-17A, IL-17F or TNFα on murine host responses to Mycobacterium tuberculosis infection by evaluating lung transcriptomic, microbiological and histological analyses. Coinciding with a significant increase of mycobacterial burden and pathological changes following TNFα blockade, gene array analyses of infected lungs revealed major changes of inflammatory and immune gene expression signatures 4 weeks post-infection. Specifically, gene expression associated with host-pathogen interactions, macrophage recruitment, activation and polarization, host-antimycobacterial activities, immunomodulatory responses, as well as extracellular matrix metallopeptidases, were markedly modulated by TNFα blockade. IL-17A or IL-17F neutralization elicited only mild changes of few genes without impaired host resistance four weeks after M. tuberculosis infection. Further, the absence of both IL-17RA and IL-22 pathways in genetically deficient mice did not profoundly compromise host control of M. tuberculosis over a 6-months period, ruling out potential compensation between these two pathways, while TNFα-deficient mice succumbed rapidly. These data provide experimental confirmation of the low clinical risk of mycobacterial infection under anti-IL-17A therapy, in contrast to anti-TNFα treatment.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos/imunologia , Interleucina-17/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Interações Hospedeiro-Patógeno/imunologia , Imunidade/imunologia , Interleucinas/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Interleucina-17/imunologia , Interleucina 22
6.
Cancer Immunol Res ; 3(2): 161-72, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25271151

RESUMO

Tryptophan catabolism by indoleamine 2,3-dioxygenase 1 (IDO1) plays a key role in tumoral resistance to immune rejection. In humans, constitutive expression of IDO1 has been observed in several tumor types. However, a comprehensive analysis of its expression in normal and tumor tissues is still required to anticipate the risks and potential benefits of IDO1 inhibitors. Using a newly validated monoclonal antibody to human IDO1, we performed an extensive immunohistochemical analysis of IDO1 expression in normal and tumor tissues. In normal tissues, IDO1 was expressed by endothelial cells in the placenta and lung and by epithelial cells in the female genital tract. In lymphoid tissues, IDO1 was expressed in mature dendritic cells with a phenotype (CD83(+), DC-LAMP(+), langerin(-), CD123(-), CD163(-)) distinct from plasmacytoid dendritic cells. Importantly, IDO1-expressing dendritic cells were not enriched in tumor-draining lymph nodes, in contrast with previously reported findings. IDO1-expressing cells were observed in a large fraction (505/866, 58%) of human tumors. They comprised tumor cells, endothelial cells, and stromal cells in proportions that varied depending on the tumor type. Tumors showing the highest proportions of IDO1-immunolabeled samples were carcinomas of the endometrium and cervix, followed by kidney, lung, and colon. This hierarchy of IDO1 expression was confirmed by gene expression data mined from The Cancer Genome Atlas database. Expression of IDO1 may be used to select tumors likely to benefit from targeted therapy with IDO1 inhibitors.


Assuntos
Biomarcadores Tumorais/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Células Cultivadas , Células Dendríticas/imunologia , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/imunologia , Genitália Feminina/imunologia , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Pulmão/imunologia , Linfonodos/imunologia , Metástase Linfática , Camundongos Endogâmicos BALB C , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Neoplasias/genética , Placenta/imunologia , Gravidez , RNA Mensageiro/genética
7.
Toxicol Sci ; 139(2): 501-11, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24690595

RESUMO

The constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) are closely related nuclear receptors involved in drug metabolism and play important roles in the mechanism of phenobarbital (PB)-induced rodent nongenotoxic hepatocarcinogenesis. Here, we have used a humanized CAR/PXR mouse model to examine potential species differences in receptor-dependent mechanisms underlying liver tissue molecular responses to PB. Early and late transcriptomic responses to sustained PB exposure were investigated in liver tissue from double knock-out CAR and PXR (CAR(KO)-PXR(KO)), double humanized CAR and PXR (CAR(h)-PXR(h)), and wild-type C57BL/6 mice. Wild-type and CAR(h)-PXR(h) mouse livers exhibited temporally and quantitatively similar transcriptional responses during 91 days of PB exposure including the sustained induction of the xenobiotic response gene Cyp2b10, the Wnt signaling inhibitor Wisp1, and noncoding RNA biomarkers from the Dlk1-Dio3 locus. Transient induction of DNA replication (Hells, Mcm6, and Esco2) and mitotic genes (Ccnb2, Cdc20, and Cdk1) and the proliferation-related nuclear antigen Mki67 were observed with peak expression occurring between 1 and 7 days PB exposure. All these transcriptional responses were absent in CAR(KO)-PXR(KO) mouse livers and largely reversible in wild-type and CAR(h)-PXR(h) mouse livers following 91 days of PB exposure and a subsequent 4-week recovery period. Furthermore, PB-mediated upregulation of the noncoding RNA Meg3, which has recently been associated with cellular pluripotency, exhibited a similar dose response and perivenous hepatocyte-specific localization in both wild-type and CAR(h)-PXR(h) mice. Thus, mouse livers coexpressing human CAR and PXR support both the xenobiotic metabolizing and the proliferative transcriptional responses following exposure to PB.


Assuntos
Ciclo Celular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fenobarbital/toxicidade , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Esteroides/genética , Transcriptoma/efeitos dos fármacos , Animais , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Receptor Constitutivo de Androstano , Perfilação da Expressão Gênica , Humanos , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenobarbital/farmacocinética , Receptor de Pregnano X , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Especificidade da Espécie , Xenobióticos/farmacocinética , Xenobióticos/toxicidade
8.
Toxicol Pathol ; 42(4): 684-95, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24448599

RESUMO

The purpose of this article is to characterize skin lesions in cynomolgus monkeys following vildagliptin (dipeptidyl peptidase-4 inhibitor) treatment. Oral vildagliptin administration caused dose-dependent and reversible blister formation, peeling and flaking skin, erosions, ulcerations, scabs, and sores involving the extremities at ≥5 mg/kg/day and necrosis of the tail and the pinnae at ≥80 mg/kg/day after 3 weeks of treatment. At the affected sites, the media and the endothelium of dermal arterioles showed hypertrophy/hyperplasia. Skin lesion formation was prevented by elevating ambient temperature. Vildagliptin treatment also produced an increase in blood pressure and heart rate likely via increased sympathetic tone. Following treatment with vildagliptin at 80 mg/kg/day, the recovery time after lowering the temperature in the feet of monkeys and inducing cold stress was prolonged. Ex vivo investigations showed that small digital arteries from skin biopsies of vildagliptin-treated monkeys exhibited an increase in neuropeptide Y-induced vasoconstriction. This finding correlated with a specific increase in NPY and in NPY1 receptors observed in the skin of vildagliptin-treated monkeys. Present data provide evidence that skin effects in monkeys are of vascular origin and that the effects on the NPY system in combination with increased peripheral sympathetic tone play an important pathomechanistic role in the pathogenesis of cutaneous toxicity.


Assuntos
Adamantano/análogos & derivados , Neuropeptídeo Y/efeitos adversos , Nitrilas/efeitos adversos , Pirrolidinas/efeitos adversos , Dermatopatias/patologia , Pele/efeitos dos fármacos , Lesões do Sistema Vascular/patologia , Adamantano/administração & dosagem , Adamantano/efeitos adversos , Administração Oral , Animais , Pressão Sanguínea/efeitos dos fármacos , Temperatura Baixa , Dipeptidases/sangue , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV , Dipeptidil Peptidases e Tripeptidil Peptidases/sangue , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Macaca fascicularis , Neuropeptídeo Y/administração & dosagem , Nitrilas/administração & dosagem , Norepinefrina/urina , Pirrolidinas/administração & dosagem , Pele/patologia , Dermatopatias/induzido quimicamente , Estresse Fisiológico , Lesões do Sistema Vascular/induzido quimicamente , Vasoconstrição/efeitos dos fármacos , Vildagliptina
9.
J Mol Histol ; 44(6): 733-47, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23880984

RESUMO

Dipeptidyl peptidase IV (DPP4) is a peptidase whose inhibition is beneficial in Type II diabetes treatment. Several evidences suggest potential implication of DPP4 in skin disorders such as psoriasis, keloids and fibrotic skin diseases where its inhibition could also be beneficial. DPP4 expression in human skin was described mainly in dermal fibroblasts and a subset of keratinocytes in the basal layer. Of importance in the perspective of preclinical experimentation, DPP4 distribution in skin of non-human primate species has not been documented. This report evidences unexpected differences between a set of human and cynomolgus monkey skin samples revealing a major expression of DPP4 in eccrine sweat glands of cynomolgus monkeys but not in humans. This represents a unique distinctive feature compared to the conserved expression of dipeptidyl peptidases 8 and 9 and potential relevant DPP4 substrates such as neuropeptide Y (NPY) and receptors (NPY-receptor 1 and Neurokinin receptor). Finally the observation that cathepsin D, an unrelated protease, shows the opposite expression compared to DPP4 (present in human but not in cynomolgus monkey eccrine sweat glands) could indicate that human eccrine sweat glands evolved a divergent protease repertoire compared to non-human primates. These unexpected differences in the eccrine sweat glands protease repertoire will need to be confirmed extending the analysis to a major number of donors but could imply possible biochemical divergences, reflecting the functional evolution of the glands and the control of their activity. Our findings also demonstrate that non-human primates studies aiming at understanding DPP4 function in skin biology are not readily translatable to human.


Assuntos
Dipeptidil Peptidase 4/metabolismo , Glândulas Écrinas/metabolismo , Adulto , Animais , Catepsina D/metabolismo , Dipeptidases/genética , Dipeptidases/metabolismo , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Macaca fascicularis , Masculino , Pessoa de Meia-Idade , Neuropeptídeo Y/metabolismo , Receptores de Neuropeptídeo Y/metabolismo
10.
Toxicol Sci ; 131(2): 375-86, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23091169

RESUMO

The molecular events during nongenotoxic carcinogenesis and their temporal order are poorly understood but thought to include long-lasting perturbations of gene expression. Here, we have investigated the temporal sequence of molecular and pathological perturbations at early stages of phenobarbital (PB) mediated liver tumor promotion in vivo. Molecular profiling (mRNA, microRNA [miRNA], DNA methylation, and proteins) of mouse liver during 13 weeks of PB treatment revealed progressive increases in hepatic expression of long noncoding RNAs and miRNAs originating from the Dlk1-Dio3 imprinted gene cluster, a locus that has recently been associated with stem cell pluripotency in mice and various neoplasms in humans. PB induction of the Dlk1-Dio3 cluster noncoding RNA (ncRNA) Meg3 was localized to glutamine synthetase-positive hypertrophic perivenous hepatocytes, suggesting a role for ß-catenin signaling in the dysregulation of Dlk1-Dio3 ncRNAs. The carcinogenic relevance of Dlk1-Dio3 locus ncRNA induction was further supported by in vivo genetic dependence on constitutive androstane receptor and ß-catenin pathways. Our data identify Dlk1-Dio3 ncRNAs as novel candidate early biomarkers for mouse liver tumor promotion and provide new opportunities for assessing the carcinogenic potential of novel compounds.


Assuntos
Biomarcadores Tumorais/genética , Impressão Genômica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Iodeto Peroxidase/genética , Neoplasias Hepáticas Experimentais/genética , Família Multigênica , RNA não Traduzido/genética , Animais , Proteínas de Ligação ao Cálcio , Receptor Constitutivo de Androstano , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Reação em Cadeia da Polimerase , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Transcriptoma , beta Catenina/metabolismo
11.
PLoS One ; 7(5): e36774, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22606287

RESUMO

BACKGROUND: Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a key transcription factor regulating a plethora of detoxifying enzymes and antioxidant genes involved in drug metabolism and defence against oxidative stress. The glucocorticoid receptor (GR) is a ligand-induced transcription factor involved in the regulation of energy supply for metabolic needs to cope with various stressors. GR activity is controlled by glucocorticoids, which are synthesized in the adrenal glands and regenerated mainly in the liver from inactive cortisone by 11ß-hydroxysteroid dehydrogenase-1 (11ß-HSD1). METHODS AND PRINCIPAL FINDINGS: Using transfected HEK-293 cells and hepatic H4IIE cells we show that glucocorticoids, activated by 11ß-HSD1 and acting through GR, suppress the Nrf2-dependent antioxidant response. The expression of the marker genes NQO1, HMOX1 and GST2A was suppressed upon treatment of 11ß-HSD1 expressing cells with cortisone, an effect that was reversed by 11ß-HSD1 inhibitors. Furthermore, our results demonstrate that elevated glucocorticoids lowered the ability of cells to detoxify H(2)O(2). Moreover, a comparison of gene expression in male and female rats revealed an opposite sexual dimorphism with an inverse relationship between 11ß-HSD1 and Nrf2 target gene expression. CONCLUSIONS: The results demonstrate a suppression of the cellular antioxidant defence capacity by glucocorticoids and suggest that elevated 11ß-HSD1 activity may lead to impaired Nrf2-dependent antioxidant response. The gender-specific differences in hepatic expression levels of 11ß-HSD1 and Nrf2 target genes and the impact of pharmacological inhibition of 11ß-HSD1 on improving cellular capacity to cope with oxidative stress warrants further studies in vivo.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Animais , Antioxidantes/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Genes Reporter , Células HEK293 , Humanos , Hidrocortisona/farmacologia , Peróxido de Hidrogênio/farmacologia , Isotiocianatos , Fígado/citologia , Masculino , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo , Ratos , Ratos Wistar , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Caracteres Sexuais , Sulfóxidos , Tiocianatos/farmacologia , Ativação Transcricional/efeitos dos fármacos , Transfecção
12.
Toxicol Sci ; 126(1): 128-39, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22193206

RESUMO

Lens explant cultures were used to assess the mechanism of drug-induced cataractogenic potential of NVS001, a peroxisome proliferator-activated receptor delta (PPARδ) agonist, which resulted in cataract in all treated animals during a 13-week rat study. Ciglitazone, a PPARγ agonist and cataractogenic compound, was used as a positive control to validate this model. Rat lenses were extracted and cultured in medium supplemented with antibiotics for 24-h preincubation pretreatment. Lenses showing no signs of damage at the end of the preincubation pretreatment period were randomized into five experimental groups, (1) untreated control, (2) 0.1% dimethyl sulphoxide control, (3) 10µM NVS001, (4) 10µM ciglitazone, and (5) 10µM acetaminophen (negative control). Lenses were treated every 24 h after preincubation pretreatment for up to 48 h. Samples for viability, histology, and gene expression profiling were collected at 4, 24, and 48 h. There was a time-dependent increase in opacity, which correlated to a decrease in viability measured by adenosine triphosphate levels in NVS001 and ciglitazone-treated lenses compared with controls. NVS001 and ciglitazone had comparable cataractogenic effects after 48 h with histology showing rupture of the lens capsule, lens fiber degeneration, cortical lens vacuolation, and lens epithelial degeneration. Furthermore, no changes were seen when lenses were treated with acetaminophen. Gene expression analysis supported oxidative and osmotic stress, along with decreases in membrane and epithelial cell integrity as key factors in NVS001-induced cataracts. This study suggests that in vitro lens cultures can be used to assess cataractogenic potential of PPAR agonists and to study/understand the underlying molecular mechanism of cataractogenesis in rat.


Assuntos
Acetatos/toxicidade , Catarata/induzido quimicamente , Proteínas do Olho/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Cristalino/efeitos dos fármacos , PPAR delta/agonistas , Tiazóis/toxicidade , Tiazolidinedionas/toxicidade , Acetatos/farmacologia , Animais , Catarata/patologia , Sobrevivência Celular/efeitos dos fármacos , Proteínas do Olho/genética , Perfilação da Expressão Gênica , Cristalino/patologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Tiazóis/farmacologia , Tiazolidinedionas/farmacologia , Técnicas de Cultura de Tecidos
13.
Nat Biotechnol ; 28(5): 463-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20458316

RESUMO

Earlier and more reliable detection of drug-induced kidney injury would improve clinical care and help to streamline drug-development. As the current standards to monitor renal function, such as blood urea nitrogen (BUN) or serum creatinine (SCr), are late indicators of kidney injury, we conducted ten nonclinical studies to rigorously assess the potential of four previously described nephrotoxicity markers to detect drug-induced kidney and liver injury. Whereas urinary clusterin outperformed BUN and SCr for detecting proximal tubular injury, urinary total protein, cystatin C and beta2-microglobulin showed a better diagnostic performance than BUN and SCr for detecting glomerular injury. Gene and protein expression analysis, in-situ hybridization and immunohistochemistry provide mechanistic evidence to support the use of these four markers for detecting kidney injury to guide regulatory decision making in drug development. The recognition of the qualification of these biomarkers by the EMEA and FDA will significantly enhance renal safety monitoring.


Assuntos
Biomarcadores Farmacológicos/urina , Clusterina/urina , Cistatina C/urina , Testes de Função Renal/métodos , Microglobulina beta-2/urina , Animais , Biomarcadores Farmacológicos/metabolismo , Distribuição de Qui-Quadrado , Clusterina/genética , Clusterina/metabolismo , Creatinina/sangue , Creatinina/metabolismo , Cistatina C/genética , Cistatina C/metabolismo , Perfilação da Expressão Gênica , Histocitoquímica , Rim/química , Rim/efeitos dos fármacos , Rim/lesões , Rim/patologia , Nefropatias/diagnóstico , Nefropatias/patologia , Glomérulos Renais/patologia , Túbulos Renais Proximais/patologia , Masculino , Prognóstico , Proteinúria/urina , Curva ROC , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Microglobulina beta-2/genética , Microglobulina beta-2/metabolismo
14.
Gynecol Obstet Invest ; 65(3): 145-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17962718

RESUMO

BACKGROUND/AIMS: Endometrial cells are chronically exposed to iron due to cyclic menstrual bleeding. Iron induces expression of adhesion molecules in endothelial cells. The purpose of this study was to investigate iron incorporation by human endometrial cells and to test whether iron may stimulate expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1. METHODS: Endometrial stromal and epithelial cells were cultured in medium alone or supplemented with INF-gamma or transferrin (Tf). Iron incorporation by cells was quantified by densitometry of ferritin immunostaining. ICAM-1 and VCAM-1 expression were evaluated at the transcriptional level by real-time RT-PCR. Membrane-bound and soluble protein levels of ICAM-1 were measured by quantitative immunohistochemistry and ELISA, respectively. RESULTS: Tf induced a significant increase in ferritin immunostaining in both endometrial cell types. Endometrial cells treated with INF-gamma expressed more ICAM-1 and VCAM-1 than untreated cells. By contrast, Tf treatment did not alter ICAM-1 and VCAM-1 expression in cultured endometrial cells. CONCLUSIONS: Endometrial cells are able to incorporate iron from Tf and to metabolize it to ferritin. Iron, unlike interferon-gamma, does not appear to be involved in the regulation of ICAM-1 and VCAM-1 expression in cultured endometrial cells.


Assuntos
Endométrio/metabolismo , Células Epiteliais/metabolismo , Molécula 1 de Adesão Intercelular/biossíntese , Interferon gama/metabolismo , Molécula 1 de Adesão de Célula Vascular/biossíntese , Células Cultivadas , Feminino , Humanos , Ferro/metabolismo
15.
Cancer Sci ; 98(12): 1831-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17900309

RESUMO

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death, and its incidence is increasing worldwide. Due to the known risk factors (mainly hepatitis B and C viruses), we believe there is a rationale for a chemopreventive approach to treat HCC. Here, based on described in vitro data, we evaluated the preventive effects of lanreotide, a somatostatin analog, on the induction of early carcinogenic events. We monitored preneoplastic foci induced by a two-stage initiation/promotion model of hepatocarcinogenesis in male Wistar rats, using diethylnitrosamine and 2-acetylaminofluorene. Lanreotide was given starting the day after the first diethylnitrosamine injection. By quantitative morphometry, we showed that lanreotide significantly decreases the size of induced preneoplastic foci. Analysis of proliferation and apoptosis assessed by immunohistochemistry, showed decreased proliferation and increased cell death in rats treated with lanreotide. As these events were associated with a significant decreased expression of the cell cycle regulator cyclin D1 and an increased expression of the cyclin-dependent kinase inhibitor p27(kip1) compared to the non-treated group, it is tempting to speculate that these factors are involved in the favorable effect of lanreotide. In conclusion, lanreotide significantly decreases early carcinogenic transformation in a two-step rat model. As lanreotide has a low toxicity profile, we believe it would be interesting to evaluate its effect in chemoprevention of HCC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Peptídeos Cíclicos/uso terapêutico , Lesões Pré-Cancerosas/prevenção & controle , Somatostatina/análogos & derivados , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Divisão Celular , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Masculino , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/patologia , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Ratos , Ratos Wistar , Somatostatina/uso terapêutico
16.
Am J Surg Pathol ; 30(10): 1243-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17001154

RESUMO

Solid pseudopapillary tumors (SPT) of the pancreas are rare neoplasms that occur mostly in young women. Despite of a low malignant potential, 10% to 15% of the cases have aggressive behavior with metastatic dissemination possibly leading to death. To date, no pathological factor can reliably predict the outcome of these tumours. Galectin-3, a major actor in the carcinogenesis of pancreatic ductal adenocarcinoma, has not been investigated in SPT. The presence of progesterone receptors is frequently reported in SPT, whereas that of estrogen receptor (ER) is unclear. We studied 5 cases of SPT consisting of 4 pancreatic tumors and 1 metastatic case. The morphological distinctive feature of metastatic nodules was the presence of polygonal or spindle cells with pleiomorphic nuclei and high mitotic count exhibiting a diffuse, infiltrative growth pattern. We found a strong expression of galectin-3 in all SPTs, whereas, interestingly, it was lower in metastatic nodules. Conversely, no galectin-3 expression was found in normal pancreatic endocrine cells or in neuroendocrine tumors. We suggest therefore that galectin-3 is a useful marker to distinguish SPT from neuroendocrine tumor, and also indicator of behavior because its low expression is associated with metastatic spreading. Moreover, the presence of galectin-3 in both SPT and pancreatic ducts rises the hypothesis of a posible ductal origin of these tumors. Specific antibodies for anti-ERalpha and anti-ERbeta demonstrated a strong expression of ERbeta whereas ERalpha was not detected. In conclusion, the present study brings the first evidence of the involvement of galectin-3 in SPT but also brought up clues which allowed to reconcile previously conflicting results on the presence of ER.


Assuntos
Adenocarcinoma Papilar/etiologia , Neoplasias Pancreáticas/etiologia , Adenocarcinoma Papilar/química , Adenocarcinoma Papilar/secundário , Biomarcadores Tumorais/análise , Núcleo Celular/patologia , Receptor beta de Estrogênio/análise , Galectina 3/análise , Humanos , Metástase Neoplásica/patologia , Pâncreas/anatomia & histologia , Pâncreas/química , Ductos Pancreáticos/química , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/patologia
17.
Horm Res ; 64(6): 266-73, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16260897

RESUMO

We report long-term evolution of endocrine functions and the results of GH treatment in 35 patients (26 male and 9 female) with pituitary stalk interruption. At diagnosis, mean chronological age was 4.8 +/- 2.7 years, mean SDS for height -3.1 +/- 0.8 with a bone age retardation of 2.3 +/- 1.3 years and a mean SDS for growth velocity of -0.5 +/- 1.1; 80% presented complete GH deficiency (GHD) and 20% partial GHD; thyroid deficiency was present in 47.1% of children with complete GHD but absent in all partial GHD. Diagnosis was made during the first months of life in only 2 patients while 23% presented with severe neonatal distress; neonatal signs were only observed in the group with pituitary height below 2 mm (45.7% of patients). GHD was isolated in 40.6% of patients below 10 years while multiple hormone deficiencies was consistent at completion of growth in all patients. Height gain was significantly higher in patients who started GH treatment before 4 years (p = 0.002). GH treatment is very effective: in 13 patients, final height was -0.4 +/- 1.0, total height gain 3.2 +/- 1.2 and distance to target height -0.3 +/- 1.6 SDS.


Assuntos
Doenças do Sistema Endócrino/etiologia , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/uso terapêutico , Doenças da Hipófise/complicações , Doenças da Hipófise/tratamento farmacológico , Hipófise/anormalidades , Adolescente , Hormônio Adrenocorticotrópico/deficiência , Criança , Pré-Escolar , Feminino , Gonadotropinas Hipofisárias/deficiência , Crescimento , Humanos , Imageamento por Ressonância Magnética , Masculino , Doenças da Hipófise/diagnóstico , Tireotropina/deficiência , Resultado do Tratamento
18.
Am J Reprod Immunol ; 54(1): 5-12, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15948767

RESUMO

PROBLEM: Intercellular adhesion molecule-1 (ICAM-1) is thought to play an important role in pathophysiological processes in endometrial tissue. The aim of this study was to quantify and compare the expression of ICAM-1 mRNA and protein in cultured endometrial epithelial cells (EEC) versus endometrial stromal cells (ESC). METHOD OF STUDY: EEC and ESC were isolated from human endometrium and cultured. At confluency, ICAM-1 mRNA was measured by real-time reverse transcriptase-polymerase chain reaction, the membrane-bound form (mICAM-1) by immunocytodensitometry, and the soluble form (sICAM-1) by enzyme-linked immunosorbent assay. RESULTS: At the transcriptional level, we observed a 1.7-fold increase in ICAM-1 expression in EEC versus ESC. mICAM-1 immunostaining in EEC [cell-relative membrane-bound signal-specific optical density (CR-M-SOD): 0.056 +/- 0.05] was stronger (P < 0.05) than in ESC (CR-M-SOD: 0.009 +/- 0.07). EEC were found to secrete more (P < 0.01) sICAM-1 ([sICAM-1] = 15.59 +/- 2.96 ng/mL) than ESC ([sICAM-1] = 5.14 +/- 2.61 ng/mL). CONCLUSIONS: Cultured EEC constitutively express significantly more ICAM-1 mRNA and protein than ESC.


Assuntos
Endométrio/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/genética , Molécula 1 de Adesão Intercelular/metabolismo , Células Estromais/metabolismo , Adulto , Biópsia , Técnicas de Cultura de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Molécula 1 de Adesão Intercelular/genética , RNA Mensageiro/genética
19.
Horm Res ; 62(1): 49-54, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15192277

RESUMO

BACKGROUND: Elevated plasma ghrelin levels have recently been reported in adults and children with Prader-Willi syndrome (PWS). The aim of the study is to investigate the relationship between obesity, growth hormone (GH) deficiency (GHD) and ghrelinemia in PWS and to examine whether hyperghrelinemia is specific to PWS. METHODS: We measured fasting ghrelinemia in children with PWS, idiopathic GHD (iGHD), obese children, controls and in 6 children presenting another congenital syndrome associated with GHD: pituitary stalk interruption (PSI). RESULTS: Children with PWS exhibited significantly higher ghrelin levels (995 pg/ml (801/1,099, median 1st/3rd quartile)) than iGHD (517 pg/ml (392/775)), obese (396 pg/ml (145/610)) and control (605 ng/ml (413/753)) children. Similar to PWS hyperghrelinemia was found in PSI children (1,029 pg/ml (705/1,151)), and was not modified by GH treatment. CONCLUSION: We conclude that hyperghrelinemia in PWS and PSI is not related to GH secretion. We hypothesize that a major site of ghrelin action is at the hypothalamic level and that a 'ghrelin resistance' syndrome may be present in these patients, primarily due to a hypothalamic defect. Combined alterations such as impaired serotonin receptor regulation associated with abnormal ghrelin responsiveness are probably responsible for obesity in PWS.


Assuntos
Modelos Biológicos , Hormônios Peptídicos/sangue , Hipófise/anormalidades , Síndrome de Prader-Willi/sangue , Envelhecimento/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Anormalidades Congênitas/sangue , Feminino , Grelina , Hormônio do Crescimento/uso terapêutico , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/metabolismo , Humanos , Masculino , Obesidade/sangue , Síndrome de Prader-Willi/tratamento farmacológico , Síndrome de Prader-Willi/metabolismo , Erros Inatos do Metabolismo de Esteroides/sangue
20.
J Neurooncol ; 66(3): 361-3, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15015669

RESUMO

A 73-year-old man with a history of malignant orbital melanoma and prostate carcinoma was admitted for progressive visual disturbance. Brain magnetic resonance imaging showed a suprasellar enhancing nodular lesion with major impingement on the anterior optical ways and sellar invasion. The extensive imaging work-up could not demonstrate with certainty its origin. Surprisingly, the transphenoidal biopsy of this patient revealed a prostate cancer metastasis outlining the importance of a histopathological diagnosis of cerebral metastases in patients with multiple malignancies when there is a doubt about the nature of the lesion.


Assuntos
Adenocarcinoma/secundário , Melanoma/secundário , Neoplasias Primárias Múltiplas/patologia , Neoplasias Orbitárias/patologia , Neoplasias Hipofisárias/secundário , Neoplasias da Próstata/patologia , Adenocarcinoma/química , Idoso , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/química , Neoplasias Encefálicas/secundário , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética , Masculino , Melanoma/química , Neoplasias Orbitárias/química , Neoplasias Hipofisárias/química , Neoplasias da Próstata/química
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