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1.
Am J Respir Crit Care Med ; 200(2): 184-198, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30964696

RESUMO

Rationale: Given the paucity of effective treatments for idiopathic pulmonary fibrosis (IPF), new insights into the deleterious mechanisms controlling lung fibroblast activation, the key cell type driving the fibrogenic process, are essential to develop new therapeutic strategies. TGF-ß (transforming growth factor-ß) is the main profibrotic factor, but its inhibition is associated with severe side effects because of its pleiotropic role. Objectives: To determine if downstream noncoding effectors of TGF-ß in fibroblasts may represent new effective therapeutic targets whose modulation may be well tolerated. Methods: We investigated the whole noncoding fraction of TGF-ß-stimulated lung fibroblast transcriptome to identify new genomic determinants of lung fibroblast differentiation into myofibroblasts. Differential expression of the long noncoding RNA (lncRNA) DNM3OS (dynamin 3 opposite strand) and its associated microRNAs (miRNAs) was validated in a murine model of pulmonary fibrosis and in IPF tissue samples. Distinct and complementary antisense oligonucleotide-based strategies aiming at interfering with DNM3OS were used to elucidate the role of DNM3OS and its associated miRNAs in IPF pathogenesis. Measurements and Main Results: We identified DNM3OS as a fibroblast-specific critical downstream effector of TGF-ß-induced lung myofibroblast activation. Mechanistically, DNM3OS regulates this process in trans by giving rise to three distinct profibrotic mature miRNAs (i.e., miR-199a-5p/3p and miR-214-3p), which influence SMAD and non-SMAD components of TGF-ß signaling in a multifaceted way. In vivo, we showed that interfering with DNM3OS function not only prevents lung fibrosis but also improves established pulmonary fibrosis. Conclusions: Pharmacological approaches aiming at interfering with the lncRNA DNM3OS may represent new effective therapeutic strategies in IPF.


Assuntos
Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/genética , RNA Longo não Codificante/genética , Fator de Crescimento Transformador beta/metabolismo , Animais , Caveolina 1/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Camundongos , MicroRNAs/metabolismo , Miofibroblastos/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Via de Sinalização Wnt
2.
BMC Nephrol ; 18(1): 282, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28870161

RESUMO

BACKGROUND: Isoniazid is the most widely used anti-tuberculosis agent, yet it may lead to life-threatening complications. CASE PRESENTATION: Here we report the case of a chronic hemodialysis patient who developed severe encephalopathy after the start of isoniazid. Blood levels of isoniazid were elevated, and acetyl-isoniazid over isoniazid ratio was decreased 3 h after intake of the medication, suggesting that a slow acetylator phenotype may have contributed to drug toxicity, in addition to pyridoxal phosphate removal by dialysis. This hypothesis was confirmed by sequencing of NAT2, the gene responsible for isoniazid elimination, and identification of NAT2 polymorphisms compatible with a slow acetylator phenotype. Isoniazid withdrawal along with supplementation using high doses of pyridoxine successfully reversed the drug toxicity. Isoniazid toxicity occurs in populations at risk, including patients with chronic kidney failure or NAT2 polymorphisms, who have a disturbed metabolism of pyridoxine or isoniazid, respectively, and those on renal replacement therapies, in whom pyridoxal phosphate - the active metabolite of pyridoxine - is inadvertently removed by dialysis. CONCLUSIONS: Physicians should be aware of the increased risk of isoniazid toxicity in patients on dialysis and in those with a slow acetylator phenotype conferred by NAT2 polymorphisms. Adaptation of prescription - either with higher doses of pyridoxine or decreased doses of isoniazid, respectively - has been suggested to reduce the risk of potentially life-threatening toxicity of isoniazid.


Assuntos
Arilamina N-Acetiltransferase/genética , Encefalopatias/genética , Isoniazida/efeitos adversos , Falência Renal Crônica/genética , Polimorfismo Genético/genética , Diálise Renal , Idoso , Antituberculosos/efeitos adversos , Encefalopatias/induzido quimicamente , Humanos , Falência Renal Crônica/terapia , Masculino , Diálise Renal/métodos , Fatores de Risco
3.
Childs Nerv Syst ; 32(12): 2403-2413, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27704245

RESUMO

OBJECTIVE: This study aims to describe the clinical and molecular presentation of pediatric neurofibromatosis type 2 (NF2) and the subsequent management of vestibular schwannomas (VS) and hearing rehabilitation. METHODS: This is a single-center retrospective study of neurofibromatosis type 2 diagnosed before the age of 18 years old from 1997. Natural history of vestibular schwannomas and surgical outcomes were evaluated using volumetric MRI, hearing, and facial nerve assessment. Patients included in chemotherapy protocols were excluded. RESULTS: From a database of 80 patients followed up for NF2 on a regular basis, 25 patients were eligible (11 sporadic cases, 14 inherited in five families). The mean age at diagnosis was 11.6 years old. The average clinical follow-up was 6.5 years. NF2 mutation was identified in 81 % of the probands. The average growth rate based on the maximum linear diameter (DGR) was 1.68 mm/year (n = 33, average follow-up 4.22 years) and 545 mm3/year in volumetric assessment (VGR) for VS larger than 1 cm (n = 21, average follow-up 3.4 years). In unoperated ears, hearing was stable in about 50 % of ears. The mean change in dB HL was 9.5 dB/year for pure-tone average and 3.5 for speech-recognition threshold (n = 34, 5.5 years 1-12). Eight children required removal through a translabyrinthine approach (mean follow-up was 4.5 years), six patients were operated on for hearing preservation (mean postoperative follow-up 4.3 years). Six patients were eligible for hearing rehabilitation with cochlear implantation (I), and five received placement of an auditory brainstem implant. CONCLUSION: Early diagnosis and treatment of small growing VS should be carefully discussed considering familial history and possible rehabilitation with a CI.


Assuntos
Correção de Deficiência Auditiva/métodos , Neurofibromatose 2/complicações , Neuroma Acústico/diagnóstico , Neuroma Acústico/etiologia , Neuroma Acústico/terapia , Adolescente , Criança , Pré-Escolar , Feminino , Testes Auditivos , Humanos , Masculino , Estudos Retrospectivos
4.
Toxicol Appl Pharmacol ; 279(3): 409-418, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25036895

RESUMO

Numerous xenobiotics have been shown to be harmful for the kidney. Thus, to improve our knowledge of the cellular processing of these nephrotoxic compounds, we evaluated, by real-time PCR, the mRNA expression level of 377 genes encoding xenobiotic-metabolizing enzymes (XMEs), transporters, as well as nuclear receptors and transcription factors that coordinate their expression in eight normal human renal cortical tissues. Additionally, since several renal in vitro models are commonly used in pharmacological and toxicological studies, we investigated their metabolic capacities and compared them with those of renal tissues. The same set of genes was thus investigated in HEK293 and HK2 immortalized cell lines in commercial primary cultures of epithelial renal cells and in proximal tubular cell primary cultures. Altogether, our data offers a comprehensive description of kidney ability to process xenobiotics. Moreover, by hierarchical clustering, we observed large variations in gene expression profiles between renal cell lines and renal tissues. Primary cultures of proximal tubular epithelial cells exhibited the highest similarities with renal tissue in terms of transcript profiling. Moreover, compared to other renal cell models, Tacrolimus dose dependent toxic effects were lower in proximal tubular cell primary cultures that display the highest metabolism and disposition capacity. Therefore, primary cultures appear to be the most relevant in vitro model for investigating the metabolism and bioactivation of nephrotoxic compounds and for toxicological and pharmacological studies.


Assuntos
Perfilação da Expressão Gênica , Rim/metabolismo , Xenobióticos/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA Complementar/biossíntese , DNA Complementar/genética , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Imunossupressores/toxicidade , Rim/efeitos dos fármacos , Nefropatias/induzido quimicamente , Nefropatias/patologia , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/efeitos dos fármacos , Modelos Biológicos , Cultura Primária de Células , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Tacrolimo/toxicidade
5.
BMC Med Genet ; 14: 35, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23506543

RESUMO

BACKGROUND: Crohn's disease (CD) is associated with elevated anti-glycans antibody response in 60% of CD patients, and 25% of healthy first-degree relatives (HFDRs), suggesting a genetic influence for this humoral response. In mice, anti-glucan antibody response depends on the NLRP3 inflammasome. Here, we explored the effect of mutated CARD8, a component of the inflammasome, on anti-glycans antibody response in human. METHODS: The association between p.C10X mutation (rs2043211) of the CARD8 gene and the levels of anti-glycans antibody response was examined in 39 CD families. The family-based QTDT association test was used to test for the genetic association between CARD8 p.C10X mutation and anti-glycan antibodies in the pedigrees. The difference in antibody responses determined by ELISA was tested in a subgroup of CD probands (one per family) and in a subgroup of HFDRs using the Wilcoxon Kruskal Wallis non-parametric test. RESULTS: The QTDT familial transmission tests showed that the p.C10X mutation of CARD8 was significantly associated with lower levels of antibody to mannans and glucans but not chitin (p=0.024, p=0.0028 and p=0.577, for ASCA, ALCA and ACCA, respectively). These associations were independent of NOD2 and NOD1 genetic backgrounds. The p.C10X mutation significantly associated or displayed a trend toward lower ASCA and ALCA levels (p=0.038 and p=0.08, respectively) only in the subgroup of CD probands. Such associations were not significant for ACCA levels in both subgroups of CD probands and of HFDRs. CONCLUSION: Our results show that ASCA and ALCA but not ACCA levels are under the influence of CARD8 genotype. Alteration of CARD8, a component of inflammasome, is associated with lower levels of antibodies directed to mannans and glucans at least in CD patients.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/genética , Doença de Crohn/genética , Doença de Crohn/imunologia , Glucanos/imunologia , Imunidade Humoral/genética , Mutação , Proteínas de Neoplasias/genética , Anticorpos/genética , Formação de Anticorpos/genética , Proteínas Adaptadoras de Sinalização CARD/imunologia , Estudos de Casos e Controles , Quitina/imunologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Inflamassomos/genética , Masculino , Mananas/imunologia , Proteínas de Neoplasias/imunologia , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Linhagem
6.
Alcohol Alcohol ; 48(4): 415-25, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23558111

RESUMO

AIMS: In response to acute ethanol consumption, tryptophan 2,3-dioxygenase (TDO) induces the kynurenine pathway (KP) through a glucocorticoid-mediated mechanism, which could lead to a dramatic accumulation of neurotoxic metabolites in association with serotonin depletion. As a result, interindividual variability in ethanol-induced behavioural disorders, such as black-outs and violent impulsive behaviours (BOVIBs) following binge drinking, could be partly explained by genetic polymorphisms affecting the KP. The aim of this study was to identify polymorphisms on the promoter of the TDO2 gene that could affect expression and/or activity of TDO through glucocorticoid induction. METHODS: Polymorphisms were screened using a PCR-sequencing strategy applied to 31 alcohol-dependent patients and 49 unrelated healthy volunteers, and functionally analysed with bioinformatic prediction tools and gene reporter assays in HepG2 and A549 cell lines. RESULTS: We identified 12 polymorphisms in the human TDO2 promoter region, 2 of them corresponding to previously unknown single-nucleotide polymorphisms (SNPs) and 3 of them located in putative glucocorticoid-responsive elements (GREs). Gene reporter assays using HepG2 and A549 cell lines confirmed the presence of several functional GREs in the promoter region of TDO2 and revealed that some of the identified polymorphisms affect the promoter activity under glucocorticoid receptor over-expression and dexamethasone exposure conditions. CONCLUSIONS: Correlational studies in larger samples could help to determine whether these polymorphisms are responsible for variations of expression and/or activity of TDO, in particular under conditions where release of glucocorticoids is increased, such as acute ethanol intake. If confirmed, such results would be of major interest in explaining part of the interindividual variability observed in behavioural responses to acute ethanol consumption.


Assuntos
Transtornos Relacionados ao Uso de Álcool/genética , Sintomas Comportamentais/genética , Glucocorticoides/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Elementos de Resposta/genética , Triptofano Oxigenase/genética , Estudos de Casos e Controles , Predisposição Genética para Doença/genética , Humanos
7.
J Toxicol Environ Health A ; 76(15): 895-906, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24156693

RESUMO

Lead (Pb) body burden and toxicity may be influenced by genetic polymorphisms. The aim of this study was to investigate the influence of G177C delta-aminolevulinic acid dehydratase (ALAD) polymorphism (rs1800435) on selected Pb exposure biomarkers in a population of workers highly exposed to this metal in the past. A cross-sectional survey was conducted between 2007 and 2009 within the cohort of ex-employees of a smelter in the north of France that closed down in 2003. A questionnaire was completed by each participant and blood samples enabled determination of Pb levels and ALAD polymorphism. Five parameters estimating the Pb body burden and its variations were studied: last blood lead level (BLL) during activity, cumulative blood Pb index, BLL at the time of the study, and absolute and percent changes in BLL after cessation of metal exposure. Multiple regression models were used to evaluate links between ALAD polymorphism and the selected Pb exposure biomarkers. Two hundred and four men were included. At the time of inclusion, the median age was 53.5 yr. The median duration of Pb exposure was 25 yr and the median latency since end of exposure was 5.6 yr. The frequency of ALAD-2 allele was 9.3%, with 34 subjects being heterozygous (ALAD1-2) and 2 homozygous (ALAD2-2). According to genotype, there was no significant difference for any of the five selected Pb exposure biomarkers. These results lend support to the notion that ALAD polymorphism exerts no marked impact on Pb body burden.


Assuntos
Predisposição Genética para Doença , Intoxicação por Chumbo/genética , Metalurgia , Doenças Profissionais/genética , Exposição Ocupacional/efeitos adversos , Polimorfismo Genético , Sintase do Porfobilinogênio/genética , Biomarcadores/sangue , Carga Corporal (Radioterapia) , Estudos de Coortes , Estudos Transversais , Humanos , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/enzimologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/sangue , Doenças Profissionais/enzimologia , Sintase do Porfobilinogênio/metabolismo , Inquéritos e Questionários , Fatores de Tempo
8.
Drug Metab Dispos ; 40(4): 694-705, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22217464

RESUMO

Intestinal cell lines are used as in vitro models for pharmacological and toxicological studies. However, a general report of the gene expression spectrum of proteins that are involved in the metabolism and the disposition of xenobiotics in these in vitro systems is not currently available. To fill this information gap, we systematically characterized the expression profile of 377 genes encoding xenobiotic-metabolizing enzymes, transporters, and nuclear receptors and transcription factors in intestinal mucosa (ileum, ascending colon, transverse colon, descending colon, and rectum) from five healthy subjects and in five commonly used intestinal cell lines (Caco-2, C2BBe1, HT29, T84, and FHC). For this, we performed a quantitative real-time reverse transcription-polymerase chain reaction analysis using TaqMan low-density arrays and analyzed the results by different statistical approaches: Spearman correlation coefficients, hierarchical clustering, and principal component analysis (PCA). A large variation in gene expression spectra was observed between intestinal cell lines and intestinal tissues. Both hierarchical clustering and PCA showed that two distinct clusters are visible, of which one corresponds to all cultured cell lines and the other to all intestinal biopsies. The best agreement between human tissue and the representative cell line was observed for human colonic tissues and HT29 and T84 cell lines. Altogether, these data demonstrated that gene expression profiling represents a new valuable tool for investigating in vitro and in vivo expression level correlation. This study has pointed out interesting expression profiles for various colon cell lines, which will be useful for choosing the appropriate in vitro model for pharmacological and toxicological studies.


Assuntos
Colo/metabolismo , Perfilação da Expressão Gênica , Mucosa Intestinal/metabolismo , Xenobióticos/metabolismo , Adulto , Idoso , Biópsia , Técnicas de Cultura de Células , Linhagem Celular , Análise por Conglomerados , Colo/enzimologia , Colo/patologia , Feminino , Expressão Gênica , Humanos , Mucosa Intestinal/enzimologia , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Componente Principal , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual , Xenobióticos/farmacocinética
9.
Drug Metab Dispos ; 40(10): 1953-65, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22798553

RESUMO

Numerous lung cell lines are currently used as in vitro models for pharmacological and toxicological studies. However, no exhaustive report about the metabolic capacities of these models in comparison with those of lung tissues is available. In the present study, we used a high-throughput quantitative real-time reverse transcription-polymerase chain reaction strategy to characterize the expression profiles of 380 genes encoding proteins involved in the metabolism and disposition of xenobiotics in 10 commonly used lung cell lines (A549, H292, H358, H460, H727, Calu-1, 16HBE, 1 HAEO, BEAS-2B, and L-132) and four primary cultures of human bronchial epithelial cells. Expression results were then compared with those previously obtained in human nontumoral and tumoral lung tissues. Our results revealed disparities in gene expression between lung cell lines or when comparing lung cell lines with primary cells or lung tissues. Primary cell cultures displayed the highest similarities with bronchial mucosa in terms of transcript profiling and therefore seem to be the most relevant in vitro model for investigating the metabolism and bioactivation of toxicants and drugs in bronchial epithelium. H292 and BEAS-2B cell lines, which exhibited the highest homology in gene expression pattern with primary cells and the lowest number of dysregulated genes compared with nontumoral lung tissues, could be used as surrogates for toxicological and pharmacological studies. Overall, our study should provide references for researchers to choose the most appropriate in vitro model for analyzing the cellular effects of drugs or airborne toxicants on the airway.


Assuntos
Neoplasias Pulmonares/metabolismo , Pulmão/metabolismo , Xenobióticos/metabolismo , Biotransformação/genética , Brônquios/metabolismo , Linhagem Celular , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ensaios de Triagem em Larga Escala , Humanos , Pulmão/enzimologia , Pulmão/patologia , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Cultura Primária de Células , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Mucosa Respiratória/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Mol Biol Rep ; 39(2): 1503-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21617944

RESUMO

The human Cytochrome P450 4A11 (CYP4A11) is a major ω-hydroxylase involved in the regulation of blood pressure in the kidney through the conversion of arachidonic acid into 20-hydroxyeicosatetraenoic acid (20-HETE). Previous studies have reported a significant association between the 8590T>C genetic variant of CYP4A11 and hypertension. Interestingly, several population-based studies have reported ethnic differences in the prevalence of hypertension, with the highest prevalence in African populations. The aim of this work was to determine the frequency and inter-ethnic comparison of the CYP4A11 (8590T>C) functional polymorphism, in five new ethnic groups: European (99 French Caucasians), African (36 Gabonese and 50 Senegalese), South American (60 Peruvians) and North African (53 Tunisians) populations, using polymerase chain reaction-single strand conformational polymorphism and sequencing strategies. We confirmed that the CYP4A11 (8590T>C) functional polymorphism exhibits inter-ethnic frequency differences. Noteworthy, the highest 8590C allele frequency was observed in the Tunisian (30.2%), followed by Senegalese (20%) populations. In addition, the CC genotype was only found in the Gabonese and Tunisian populations (5.6% and 8.4%, respectively). These populations may be of major interest to help to clarify the linkage between hypertension and CYP4A11 (8590T>C) genotype in African populations. These findings provide data for further studies that investigate the potential association of CYP4A11 (8590T>C) variant with an incidence of hypertension genesis in respect of ethnicity.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Etnicidade/genética , Variação Genética , Hipertensão/genética , Polimorfismo de Nucleotídeo Único/genética , Sequência de Bases , Primers do DNA/genética , Frequência do Gene , Genótipo , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA
11.
Nutrients ; 14(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35565854

RESUMO

Previously, the in vitro growth of cancer stem cells in the form of tumor spheres from five different brain cancer cell lines was found to be methionine-dependent. As this earlier work indicated that ALDH1L2, a folate-dependent mitochondria aldehyde dehydrogenase gene, is upregulated in glioblastoma stem cells, we invalidated this gene using CRISPR-cas 9 technique in this present work. We reported here that this invalidation was effective in U251 glioblastoma cells, and no cas9 off target site could be detected by genome sequencing of the two independent knockout targeting either exon I or exon III. The knockout of ALDH1L2 gene in U251 cells rendered the growth of the cancer stem cells of U251 methionine independent. In addition, a much higher ROS (reactive oxygen radicals) level can be detected in the knockout cells compared to the wild type cells. Our evidence here linked the excessive ROS level of the knockout cells to reduced total cellular NADPH. Our evidence suggested also that the cause of the slower growth of the knockout turmor sphere may be related to its partial differentiation.


Assuntos
Glioblastoma , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Humanos , Metionina/metabolismo , Células-Tronco Neoplásicas/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
12.
Pharmacogenet Genomics ; 21(6): 313-24, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21372752

RESUMO

BACKGROUND: Adverse effects of thiopurine drugs occur in 15-28% of patients and the majority is not explained by thiopurine-S-methyltransferase deficiency. Furthermore, approximately 9% of patients with inflammatory bowel disease are resistant to azathioprine therapy. Recently, the small guanosine triphosphatase, Rac1, was identified as an important molecular target of 6-thioguanine triphosphate, one of the active metabolite of thiopurines such as azathioprine. To date, no functional genetic polymorphism of the human Rac1 gene had been reported. OBJECTIVES: Evidence for functional genetic polymorphisms of the human Rac1 gene and to investigate their relative contribution to the development of toxicity induced by azathioprine treatment in patients with inflammatory bowel disease. METHODS: We first screened for polymorphisms in the Rac1 gene in genomic DNA samples from 92 unrelated Caucasian individuals. The functional consequences of identified polymorphisms were assessed in vitro using transient transfection assays in Jurkat and A549 cell lines. The relationship between polymorphisms of Rac1 and thiopurine response or hematotoxicity was studied in 128 patients under thiopurine treatment. RESULTS: Three single nucleotide polymorphism and one variable number tandem repeat were identified in the promoter region of Rac1 gene. Interestingly, in Jurkat T cells, the c.-289G>C substitution and c.-283_-297[3] variable number tandem repeat displayed a significantly increased promoter activity (P<0.01) of 150 and 300%, respectively, compared with that of the wild-type sequence. Patients with thiopurine-S-methyltransferase mutations presented a significantly increased probability of developing hematotoxicity (odds ratio=5.68, 95% confidence interval=1.45-22.23, P=0.00625). Moreover, among the 75 patients who did not develop hematotoxicity, there was a marginally overrepresentation of functional genetic polymorphisms of Rac1 (odds ratio=0.18, 95% confidence interval=0.02-1.49, P=0.079). CONCLUSION: This study constitutes the first report of a functional genetic polymorphism that could affect Rac1 expression and thus modulate the risk of adverse drug reaction in patients under thiopurine treatment. A larger scale (case-control) study should enable us to confirm or cancel these preliminary results.


Assuntos
Azatioprina/uso terapêutico , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/genética , Polimorfismo Genético/genética , Proteínas rac1 de Ligação ao GTP/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Metiltransferases , Pessoa de Meia-Idade , Mutagênese Sítio-Dirigida , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Regiões Promotoras Genéticas , Estudos Retrospectivos , Adulto Jovem
13.
Nephrol Dial Transplant ; 26(9): 3046-50, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21677300

RESUMO

BACKGROUND: The effect of potentially relevant genetic polymorphisms, CYP3A5 6986A>G and ABCB1 3435C>T, on Tacrolimus pharmacokinetics and graft clinical outcome was investigated in donor and recipient DNA samples from 209 kidney transplant patients. METHODOLOGY/PRINCIPAL FINDINGS: The mean follow-up was 21.8 ± 9 months. The Tacrolimus dose, trough blood concentrations (C0) and C0/dose ratio were only statistically correlated with the recipient CYP3A5 genotype. CYP3A5 and ABCB1 genotypes appeared to have no influence on the incidence of Biopsy Proven Acute Rejection and Delayed Graft Function. Renal function was not affected by CYP3A5 and ABCB1 genotypes. Histological evaluation of biopsies revealed also no significant association between Tacrolimus toxicity features and donor or recipient CYP3A5 and ABCB1 polymorphisms. Tacrolimus sparing appeared to be independent of CYP3A5 and ABCB1 genotypes. CONCLUSIONS/SIGNIFICANCE: Recipient CYP3A5 6986A>G polymorphism explains part of the interindividual variability of the pharmacokinetics of Tacrolimus. The clinical outcome at 2-year follow-up does not appear to be related to the donor or recipient CYP3A5 6986A>G and/or ABCB1 3435C>T polymorphisms.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Citocromo P-450 CYP3A/genética , Rejeição de Enxerto/mortalidade , Imunossupressores/administração & dosagem , Transplante de Rim/mortalidade , Polimorfismo de Nucleotídeo Único/genética , Tacrolimo/administração & dosagem , Subfamília B de Transportador de Cassetes de Ligação de ATP , Relação Dose-Resposta a Droga , Feminino , Genótipo , Humanos , Imunossupressores/farmacocinética , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Tacrolimo/farmacocinética , Distribuição Tecidual
14.
Mol Biol Rep ; 38(8): 5185-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21181270

RESUMO

Human type II inosine monophosphate dehydrogenase (IMPDH2) is a key enzyme in the purine nucleotide biosynthetic pathway and constitutes a pivotal biological target for immunosuppressant and antiviral drugs. Several Single Nucleotide Polymorphisms (SNP) affecting the IMPDH2 gene sequence have been reported with potential functional relevance and could impact drugs response. We aimed to determine the frequency of three of these polymorphisms, namely g.3375C>T (Leu(263)Phe), c.-95T>G and IVS7+10T>C, in Caucasians, Tunisians, Peruvians and Black Africans (Gabonese and Senegalese). The g.3375C>T and c.-95T>G polymorphisms are rare with a Minor Allele Frequency ≤1.0% in our populations, whereas the third variant, IVS7+10T>C, is more frequent and displays large interethnic variations, with an allelic frequency ranging from 14.6% in the French Caucasian population studied to less than 2% in Black African and Peruvian populations. This ethnic-related data might contribute to a better understanding of the variability in clinical outcome and/or dose adjustments of drugs that are IMPDH inhibitors such as mycophenolic acid.


Assuntos
Etnicidade/genética , IMP Desidrogenase/genética , Polimorfismo de Nucleotídeo Único/genética , Frequência do Gene/genética , Genótipo , Humanos , Taxa de Mutação
15.
Eur J Clin Pharmacol ; 67(8): 855-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21691803

RESUMO

BACKGROUND: Tramadol is a synthetic, centrally acting analgesic for the treatment of moderate to severe pain. The marketed tramadol is a racemic mixture containing 50% (+)tramadol and 50% (-)tramadol and is mainly metabolized to O-desmethyltramadol (M1) by the cytochrome P450 CYP2D6. Tramadol is generally considered to be devoid of any serious adverse effects of traditional opioid receptor agonists, such as respiratory depression and drug dependence. CASE REPORT: A 22-year-old Caucasian female patient was admitted to our ICU in refractory cardiac arrest requiring extracorporeal membrane oxygenation. This aggressive support allowed resolution of multi-organ dysfunction syndrome. Repeated blood analyses using liquid chromatography-tandem mass spectrometry confirmed high concentrations of both tramadol and its main metabolite O-desmethyltramadol. Genotyping of CYP2D6 revealed the patient to be heterozygous for a duplicated wild-type allele, predictive of a CYP2D6 ultrarapid metabolizer (UM) phenotype, confirmed by calculation of the tramadol/M1 (MR1) metabolic ratio at all time points. DISCUSSION: We here report a case of near-fatal isolated tramadol cardiotoxicity. Because of the inhibition of norepinephrine reuptake, excessive blood epinephrine levels in this CYP2D6R UM patient following excessive tramadol ingestion could explain the observed strong myocardial stunning. This patient admitted intermittent tramadol consumption to gain a "high" sensation. In patients with excessive morphinomimetic effects, levels of tramadol and its main metabolite M1could be measured, ideally combined with CYP2D6 genotyping, to identify individuals at risk of tramadol-related cardiotoxicity. Tramadol treatment could be optimized in these at-risk individuals, consequently improving patient outcome and safety.


Assuntos
Analgésicos Opioides/intoxicação , Citocromo P-450 CYP2D6/metabolismo , Miocárdio Atordoado/induzido quimicamente , Tramadol/intoxicação , Adulto , Analgésicos Opioides/sangue , Analgésicos Opioides/farmacocinética , Citocromo P-450 CYP2D6/genética , Monitoramento de Medicamentos , Overdose de Drogas , Epinefrina/sangue , Feminino , Genótipo , Parada Cardíaca/etiologia , Humanos , Desintoxicação Metabólica Fase I , Miocárdio Atordoado/sangue , Miocárdio Atordoado/fisiopatologia , Transtornos Relacionados ao Uso de Opioides/psicologia , Tramadol/análogos & derivados , Tramadol/sangue , Tramadol/farmacocinética , Adulto Jovem
16.
Front Endocrinol (Lausanne) ; 12: 718917, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690927

RESUMO

Introduction: Cytochrome P450 2D6, 3A4 and 3A5 are involved in the metabolism of many drugs. These enzymes have a genetic polymorphism responsible for different metabolic phenotypes. They play a role in the metabolism of clomiphene citrate (CC), which is used to induce ovulation. Response to CC treatment is variable, and no predictive factors have thus far been identified. Objective: To study a possible link between the cytochrome P450 2D6, 3A4 and 3A5 polymorphisms and clinical response to CC. Study Design: Seventy-seven women with anovulatory Polycystic Ovarian Syndrome (PCOS) treated with CC were included which determined their cytochrome P450 2D6, 3A4 and 3A5 genotypes and used the results to predict ovarian response to this drug. Predicted responses based on the cytochrome genotypes were compared with the observed clinical responses using the calculation of a weighted Kappa coefficient. Main Outcome Measures: Number of dominant follicles assessed by ultrasound at the end of the follicular phase and confirmation of ovulation by blood progesterone assay in the luteal phase. Results: Concordance between the predicted and observed responses for the combination of the three cytochromes was 36.71%, with a negative Kappa coefficient (K = -0.0240), which corresponds to a major disagreement. Similarly, for predictions based on the cytochrome P450 2D6 genotype alone, only 39.24% of predictions were verified (coefficient K = -0.0609). Conclusion: The genetic polymorphism of cytochromes P450 2D6, 3A4 and 3A5 does not appear to influence clinical response to CC used to induce ovulation in anovulatory PCOS women.


Assuntos
Anovulação , Clomifeno/uso terapêutico , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP3A/genética , Síndrome do Ovário Policístico , Adulto , Anovulação/tratamento farmacológico , Anovulação/genética , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , França , Estudos de Associação Genética , Humanos , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/genética , Variantes Farmacogenômicos/genética , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único/fisiologia , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
17.
Tunis Med ; 99(2): 215-220, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33899189

RESUMO

Progressive familial intrahepatic is a heterogeneous group of rare autosomal recessive liver disorders. Neonatal onset is characteristic of the PFIC 1 and PFIC 2, which result from mutations in genes respectivelyATP8B1 and ABCB11. Four Tunisian patients, three of them with PFIC 2 and one with PFIC1, were described. They all had typical clinical and biological features. However, they all had newly reported mutations. The same mutation was found in the patients with PFIC2, which could facilitate the diagnosis in Tunisian patients suspected in the future. The patient diagnosed with PFIC1 had also a newly described mutation, with a probable phenotypic particularity that is congenital hypothyroidism. Advances are being made to establish a molecular diagnosis in neonatal onset cholestasis. Indeed, next generation sequencing gene panels (NGSGP) potentially decrease the need for invasive procedures in these patients, enable early initiation of treatment and adequate genetic counseling.


Assuntos
Colestase Intra-Hepática , Colestase , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/epidemiologia , Colestase Intra-Hepática/genética , Humanos , Recém-Nascido , Mutação
18.
J Pers Med ; 11(10)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34683143

RESUMO

The pharmacokinetic variability of tacrolimus can be partly explained by CYP3A5 activity. Our objective was to evaluate a tacrolimus sparing policy on renal graft outcome according to CYP3A5 6986A>G genetic polymorphism. This retrospective study included 1114 recipients with a median follow-up of 6.3 years. Genotyping of the 6986A>G allelic variant corresponding to CYP3A5*3 was systematically performed. One year after transplantation, tacrolimus blood trough concentration (C0) target range was 5-7 ng/mL. However, daily dose was capped to 0.10 mg/kg/day regardless of the CYP3A5 genotype. A total 208 CYP3A5*1/- patients were included. Despite a higher daily dose, CYP3A5*1/- recipients exhibited lower C0 during follow-up (p < 0.01). Multivariate analysis did not show any significant influence of CYP3A5*1/- genotype (HR = 0.70, 0.46-1.07, p = 0.10) on patient-graft survival. Glomerular Filtration Rate (GFR) decline was significantly lower for the CYP3A5*1/- group (p = 0.02). The CYP3A5*1/- genotype did not significantly impact the risk of biopsy-proven acute rejection (BPAR) (HR = 1.01, 0.68-1.49, p = 0.97) despite significantly lower C0. Based on our experience, a strategy of tacrolimus capping is associated with a better GFR evolution in CYP3A5*1/- recipients without any significant increase of BPAR incidence. Our study raised some issues about specific therapeutic tacrolimus C0 targets for CYP3A5*1/- patients and suggests to set up randomized control studies in this specific population.

19.
NPJ Genom Med ; 5: 38, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33024573

RESUMO

Next-generation sequencing has revolutionized the molecular diagnosis of individuals affected by genetic kidney diseases. Indeed, rapid genetic testing in individuals with suspected inherited nephropathy has not only important implications for diagnosis and prognosis but also for genetic counseling. Nephronophthisis (NPHP) and related syndromes, a leading cause of end-stage renal failure, are autosomal recessive disorders characterized by the variable presentation and considerable locus heterogeneity with more than 90 genes described as single-gene causes. In this case report, we demonstrate the utility of whole-genome sequencing (WGS) for the molecular diagnosis of NPHP by identifying two putative disease-causing intronic mutations in the NPHP3 gene, including one deep intronic variant. We further show that both intronic variants, by affecting splicing, result in a truncated nephrocystin-3 protein. This study provides a framework for applying WGS as a first-line diagnostic tool for highly heterogeneous disease such as NPHP and further suggests that deep intronic variations are an important underestimated cause of monogenic disorders.

20.
Am J Gastroenterol ; 104(7): 1745-53, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19471251

RESUMO

OBJECTIVES: Anti-Saccharomyces cerevisiae antibodies (ASCAs) are present in 50-60% of patients with Crohn's disease (CD) and in 20-25% of their healthy relatives (HRs). The yeast, Candida albicans, has been shown to generate ASCAs, but the presence of C. albicans in the digestive tract of CD patients and their HRs has never been investigated. Therefore, we studied C. albicans carriage in familial CD and its correlation with ASCAs. METHODS: Study groups consisted of 41 CD families composed of 129 patients and 113 HRs, and 14 control families composed of 76 individuals. Mouth swabs and stool specimens were collected for isolation, identification, and quantification of yeasts. Serum samples were collected for detection of ASCAs and anti-C. albicans mannan antibodies (ACMAs). RESULTS: C. albicans was isolated significantly more frequently from stool samples from CD patients (44%) and their HRs (38%) than from controls (22%) (P<0.05). The prevalence of ACMAs was similar between CD patients, their HRs, and controls (22, 19, and 21%, respectively, P=0.845), whereas the prevalence of ASCAs was significantly increased in CD families (72 and 34% in CD and HRs, respectively, in contrast to 4% in controls, P<0.0001). AMCA levels correlated with C. albicans colonization in all populations. ASCA levels correlated with C. albicans colonization in HRs but not in CD patients. CONCLUSIONS: CD patients and their first-degree HRs are more frequently and more heavily colonized by C. albicans than are controls. ASCAs correlate with C. albicans colonization in HRs but not in CD. In HRs, ASCAs could result from an altered immune response to C. albicans. In CD, a subsequent alteration in sensing C. albicans colonization could occur with disease onset.


Assuntos
Candida albicans/genética , Candidíase/genética , Doença de Crohn/genética , Doença de Crohn/microbiologia , Saccharomyces cerevisiae/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Anticorpos Antifúngicos/análise , Candida albicans/imunologia , Candidíase/imunologia , Estudos de Casos e Controles , Contagem de Colônia Microbiana , Ensaio de Imunoadsorção Enzimática , Feminino , França , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Linhagem , Probabilidade , Valores de Referência , Medição de Risco , Saccharomyces cerevisiae/imunologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Leveduras/genética , Leveduras/imunologia , Adulto Jovem
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