Association of BDNF, HTR2A, TPH1, SLC6A4, and COMT polymorphisms with tDCS and escitalopram efficacy: ancillary analysis of a double-blind, placebo-controlled trial

Objective: We investigated whether single nucleotide polymorphisms (SNPs) associated with neuroplasticity and activity of monoamine neurotransmitters, such as the brain-derived neurotrophic factor (BDNF, rs6265), the serotonin transporter (SLC6A4, rs25531), the tryptophan hydroxylase 1 (TPH1, rs1800532), the 5-hydroxytryptamine receptor 2A (HTR2A, rs6311, rs6313, rs7997012), and the catechol-O-methyltransferase (COMT, rs4680) genes, are associated with efficacy of transcranial direct current stimulation (tDCS) in major depression. Methods: Data from the Escitalopram vs. Electrical Current Therapy for Treating Depression Clinical Study (ELECT-TDCS) were used. Participants were antidepressant-free at baseline and presented with an acute, moderate-to-severe unipolar depressive episode. They were randomized to receive escitalopram/tDCS-sham (n=75), tDCS/placebo-pill (n=75), or placebo-pill/sham-tDCS (n=45). General linear models assessed the interaction between treatment group and allele-wise carriers. Additional analyses were performed for each group and each genotype separately. Results: Pairwise group comparisons (tDCS vs. placebo, tDCS vs. escitalopram, and escitalopram vs. placebo) did not identify alleles associated with depression improvement. In addition, exploratory analyses also did not identify any SNP unequivocally associated with improvement of depression in any treatment group. Conclusion: Larger, combined datasets are necessary to identify candidate genes for tDCS response.

Enzymatic potential of heterotrophic bacteria from a neutral copper mine drainage

Abstract Copper mine drainages are restricted environments that have been overlooked as sources of new biocatalysts for bioremediation and organic syntheses. Therefore, this study aimed to determine the enzymatic activities (esterase, epoxide hydrolase and monooxygenase) of 56 heterotrophic bacteria isolated from a neutral copper mine drainage (Sossego Mine, Canaã dos Carajás, Brazil). Hydrolase and monooxygenase activities were detected in 75% and 20% of the evaluated bacteria, respectively. Bacterial strains with good oxidative performance were also evaluated for biotransformation of organic sulfides. Fourteen strains with good enzymatic activity were identified by 16S rRNA gene sequencing, revealing the presence of three genera: Bacillus, Pseudomonas and Stenotrophomonas. The bacterial strains B. megaterium (SO5-4 and SO6-2) and Pseudomonas sp. (SO5-9) efficiently oxidized three different organic sulfides to their corresponding sulfoxides. In conclusion, this study revealed that neutral copper mine drainages are a promising source of biocatalysts for ester hydrolysis and sulfide oxidation/bioremediation. Furthermore, this is a novel biotechnological overview of the heterotrophic bacteria from a copper mine drainage, and this report may support further microbiological monitoring of this type of mine environment.

Polimorfismos de los genes cytochrome P450 y VKORC1 afectan la terapia anticoagulante oral / Polymorphisms of cytochrome P450 genes and VKORC1 affect the oral anticoagulant therapy

Los llamados factores vitaminas k dependientes (FII, FVII, FIXy FX), requieren ser carboxilados por la enzima gamma carboxilasa de los hepatocitos para ser funcionales. Esta enzima utiliza como cofactor vitamina K reducida, condición que se logra por acción de la enzima epóxido reductasa. Los anticoagulantes orales (ACO) son antagonistas de la vitamina K, quedando esta última en forma oxidada, no pudiendo actuar como cofactor. La variabilidad interindividual del tratamiento anticoagulante (TAC) se explica por factores ambientales, desconocidos y genéticos. Entre estos últimos los polimorfismos genéticos del cytochrome P450 (CYP2C9) y de la vitamina K epóxido reductasa (VKOR), los cuales se han relacionado con la variación en las dosis de ACO en distintas poblaciones del mundo. En dicho contexto se muestran resultados preliminares de un polimorfismo de CYP2C9 obtenidos en el Programa de Investigación de Factores de Riesgo de Enfermedades Cardiovasculares (PIFRECV). Además se describen brevemente otros polimorfismos que podrían influir sobre la variabilidad en la respuesta al TAC.

Effects of light on the feedback control of GA-20 oxidase gene homolog in DongJinByeo seedlings.

The effects of gibberellin (GA) on the expression of GA-20 oxidase gene homolog were examined in light-grown seedlings and dark-grown seedlings of DongJinByeo. The growth rates of the stems of etiolated seedlings were faster than those of green seedlings. However, upon addition of GA to these seedlings, the stem growth rates of green seedlings were faster than those of etiolated seedlings. To understand the molecular mechanism of GA gene regulation in DongJinByeo, total RNA from DongJinByeo was hybridized with cDNA of GA-20 oxidase gene homolog. Greater accumulation of transcript of GA-20 oxidase gene homolog was observed in green seedlings than in etiolated seedlings. However, upon addition of GA, higher accumulation of the gene transcript was found in etiolated seedlings than in green seedlings, indicating that expression of the transcript of GA-20 oxidase gene homolog might be inhibited by light. These results suggest that light might regulate feedback control of the transcript of GA-20 oxidase gene homolog in DongJinByeo.

Influence of the CYP2C9 AND CYP2C19 polymorphisms on phenytoin hydroxylation in healthy individuals from south India.

BACKGROUND AND OBJECTIVES: Phenytoin, a widely used anti-epileptic drug, is metabolized mainly by CYP2C9 (90%) and partly by CYP2C19 (10%) to its major metabolite 5-(para-hydroxyphenyl)-5- phenylhydantoin (p-HPPH). The CYP2C9 and CYP2C19 genes encoding these enzymes are polymorphically expressed and most of the variants result in decreased metabolism of the respective substrates. The present study was undertaken to investigate the influence of the CYP2C9*2 and *3 as well as CYP2C19*2 and *3 variant genotypes on phenytoin hydroxylation in healthy subjects from south India. METHODS: A total of 27 healthy, unrelated, subjects were administered a single oral dose of 300 mg phenytoin. Four hours later, 5 ml of blood was collected and genotyped for CYP2C9*1, *2, *3, CYP2C19*1, *2 and *3 by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Phenytoin and the major metabolite p-HPPH were estimated by reverse phase HPLC. The metabolic ratio was calculated as concentration of phenytoin/p-HPPH. RESULTS: A significant correlation was observed between the CYP2C9 genotype and metabolic ratio of phenytoin/p-HPPH (r = 0.472, 95% CI 0.100 to 0.728; P = 0.01). While no association was found with CYP2C19 alone, a significant correlation was observed between the combined CYP2C9 and CYP2C19 genotypes and phenytoin metabolic ratio (r = 0.507, 95% CI 0.146 to 0.749; P< 0.01). INTERPRETATION AND CONCLUSION: CYP2C9*2 and *3 mutant alleles caused decreased hydroxylation of phenytoin in vivo, whereas the mutant alleles of CYP2C19 played only a minor role in the metabolism of phenytoin in subjects of our study. The results of present preliminary study needs to be confirmed with a larger sample.

CYP2A6 and CYP2E1 polymorphisms in a Brazilian population living in Rio de Janeiro

Cytochrome P450 (CYP) is a superfamily of enzymes involved in the metabolism of endogenous compounds and xenobiotics. CYP2A6 catalyzes the oxidation of nicotine and the activation of carcinogens such as aflatoxin B1 and nitrosamines. CYP2E1 metabolizes ethanol and other low-molecular weight compounds and can also activate nitrosamines. The CYP2A6 and CYP2E1 genes are polymorphic, altering their catalytic activities and susceptibility to cancer and other diseases. A number of polymorphisms described are ethnic-dependent. In the present study, we determined the genotype and allele frequencies of the main CYP2A6 and CYP2E1 polymorphisms in a group of 289 volunteers recruited at the Central Laboratory of Hospital Universitário Pedro Ernesto. They had been residing in the city of Rio de Janeiro for at least 6 months and were divided into two groups according to skin color (white and non-white). The alleles were determined by allele specific PCR (CYP2A6) or by PCR-RFLP (CYP2E1). The frequencies of the CYP2A6*1B and CYP2A6*2 alleles were 0.29 and 0.02 for white individuals and 0.24 and 0.01 for non-white individuals, respectively. The CYP2A6*5 allele was not found in the population studied. Regarding the CYP2E1*5B allele, we found a frequency of 0.07 in white individuals, which was statistically different (P < 0.05) from that present in non-white individuals (0.03). CYP2E1*6 allele frequency was the same (0.08) in both groups. The frequencies of CYP2A6*1B, CYP2A6*2 and CYP2E1*6 alleles in Brazilians are similar to those found in Caucasians and African-Americans, but the frequency of the CYP2E1*5B allele is higher in Brazilians.

Efficacy of Triple Therapy with Rabeprazole for Helicobacter pylori Infection in relation to CYP2C19 Genotype / 대한소화기학회지

BACKGROUND/AIMS: Genetic polymorphism of cytochrome P450 CYP2C19 influences the efficacy of proton pump inhibitor (PPI) in Helicobacter pylori (H. pylori) eradication therapy. We investigated the difference in the cure rates of H. pylori infection by triple (rabeprazole plus amoxacillin and clarithromycin) therapy in relation to CYP2C19 genotype status. METHODS: One hundred and sixteen H. pylori infected patients with gastric ulcer and duodenal ulcer completed the triple therapy with 10 mg of rabeprazole b.i.d., 1,000 mg amoxacillin b.i.d. and 500 mg of clarithromycin b.i.d. for one week. The genotype of CYP2C19 was determined by a PCR-restriction fragment length polymorphism method. RESULTS: According to the univariate analysis, heterozygous extensive metabolizers (hetero EMs) and poor metabolizers (PMs) showed the highest (87.0%) and the lowest (80.0%) eradication rates, respectively. The difference in the therapeutic efficacy of rabeprazole among the different CYP2C19 genotypes was insignificant. With regard to gender, age and smoking history in relation to eradication rate, a statistical significance was noted only with age with odds ratio of 1.063 and p-value of 0.0202. CONCLUSIONS: In the eradication therapy of H. pylori, no statistically significant difference in therapeutic efficacy of rabeprazole was found among different CYP2C19 genotypes.

La biodiversidad humana y sus efectos sobre la variabilidad farmacologica: enzimas CYP2D6 y NAT2 en poblaciones amerindias de Panama, Colombia y Costa Rica / Human biodiversity and its effects on the pharmacological variability: CYP2D6 and NAT2 enzymes in Amerind populations of Panama, Colombia and Costa Rica

Human biodiversity originates partially from human microevolution, which have produced different populations. This biodiversity is responsible for most of the variability in drug response. We present the methodology employed in population pharmacology studies and general information about the CYP2D6 and NAT2 systems. We report results obtained in Embera and Ngawbe Amerindians, who are characterized by a low phenotypic and genotypic CYP2D6 diversity. In regard to NAT2, Amerindians are distinguished by a high allelic frequency of S3 and low ones of S1 and S2, situation which is reversed in Caucasians

Nuevos conceptos en hiperplasia suprarrenal virilizante (HSRV) por bloqueo de la 21-hidroxilasa / New concepts in virilizing adrenal hyperplasia due to 21-hydroscylase blocking

El estudio del haplotipo HLA en una familia, cuando hay un caso conocido de HSRV (perdedora o no perdedora de sal) es útil en la práctica para identificar heterozigotos, portadores sanos de la enfermedad y permite dar consejo genético a las parejas. El haplotipo HLA es útil en el diagnóstico intrauterino de la enfermedad, a partir del estudio del líquido amniótico en embarazadas parientes de un apaciente con HSRV. El haplotipo HLA también puede ser útil para identificar otros pacientes en una familia con un caso de la forma no clásica o post-puberal de la enfermedad y ayuda a hacer un diagnóstico precoz, especialmente en el sexo masculino, en que los signos físicos de esta forma clínica son muy difíciles de detectar. El haplotipo HLA hasta el presente no sirve para identificar enfermos ni portadores en la población general, ya que no funciona como un marcador genético y no hay asociación entre un haplotipo HLA determinado y la enfermedad en la población general. La 17-OHP es útil en el diagnóstico de todas las formas clínicas de HSRV. En el RN la 17-OHP está elevada precozmente y es de gran ayuda, ya que en estos casos los 17KS y el PNT urinario generalmente no se elevan significativamente. La determinación de 17-OHP por RIA en muestras de sangre tomadas en papel filtro pueden ser usadas para el rastreo de la enfermedad en los RN de una población con alta incidência de la afección. El estudio de 17-OHP, después del estímulo con ACTH, puede permitir detectar pacientes con formas no clásicas de la enfermedad e identificar alrededor del 75% de los portadores sanos (heterozigotos). La interpretación cuidadosa de las concentraciones plasmáticas de 17-OHP en dos horarios del día (8 AM y 5 PM) es útil en el control del tratamiento de los pacientes pediátricos. La testosterona plasmática (en mujeres de cualquier edad y en niños entre 1 y 9 años) y la - 4 - androstenediona plasmática (en ambos sexos sin importar edad) son útiles para controlar el tratamiento de estos pacientes si se consideran en conjunto con los criterios clásicos y con otros más recientes que se comentan en esta publicación. La actividad aumentada de renina plasmática en sujetos con HSRV es un criterio biológico moderno para identificar pacientes perdedores de sal, aunque clínicamente nunca hayan presentado crisis de pérdida de sal y para decidir si es necesario agregar mineralocorticoides al tratamiento