Avaliação do estado nutricional relativo ao selênio e da expressão gênica de selenoproteínas em pacientes com aterosclerose tratados com estatinas

The aim of this study was to determine the effects of the use of rosuvastatin in patients with atherosclerosis, in relation to blood parameters of selenium and selenoproteins, and also observe possible changes in gene expression of selenoproteins in these patients. The sample consisted of 27 adult and elderly patients with a clinical diagnosis of coronary artery disease undergoing angioplasty, treated at Natal Hospital Center hospital, Natal, RN. Patients were treated with rosuvastatin 10 mg/day during four months. Anthropometric variables such as body mass index (BMI) and Waist circumference (WC) were measured before and after treatment, as well as lipid profile, blood glucose and liver enzymes (AST and ALT). The diet of the patients was also analyzed using 24-hour diet recall. We analyzed the concentrations of selenium in plasma and erythrocytes, and also the activity of Glutathione Peroxidase and gene expression by Real Time PCR of selenoproteins GPx1, SelP1 and SelN1. Patients had mean age of 61.0 ± 9.4 years, 59.3% were men and 40.7% were women. After four months of treatment there was significant reduction of CA and, according to BMI, most were overweight. The intake of macronutrients, cholesterol, polyunsaturated fatty acids, monounsaturated and saturated was adequate, but the energy and fiber intake was below the recommendations. Regarding the selenium intake was observed a high prevalence of inadequacy. As expected, after treatment with rosuvastatin, a significant reduction in total cholesterol, LDL and glucose, which was not observed for HDL. Selenium concentrations in plasma and erythrocytes showed no changes, keeping within the established cutoffs. We observed a significant increase in GPx enzyme activity and mRNA expression of GPX1 and SEPN1, but not for gene SEPP1. Thus, it was found that treatment with rosuvastatin did not reduce the expression of selenoproteins. More studies are needed to clarify the effects of rosuvastatin on gene expression of selenoproteins in patients with atherosclerosis

Avaliação do status de zinco e da expressão gênica de metalotioneínas em pacientes com aterosclerose tratados com rosuvastatina

The study had as objective to evaluate the zinc status by means of dietary intake, zinc in plasma and in erythrocytes and the metallothionein gene expression in patients with atherosclerosis in use of rosuvastatin. The research involved 27 adult and elderly patients of both genders with atherosclerosis that were treated with rosuvastatin (10mg/day) during 4 months. We performed the dosage of lipids, glucose, AST and ALT, ultrasensitive C-reactive protein (hsCRP), plasmatic and erythrocyte zinc and 1 and 2 metallothionein gene expression. The assessment of body mass index (BMI) and abdominal circumference (AC) was performed, besides the analysis of dietary intake of patients. The majority of the evaluated patients presented overweight, before and after the treatment, with no significant difference between the times of the study. It was identified that the AC was significantly reduced in the group (p<0.05) after the intervention. The majority of the patients had intake below the recommendation of calories and fibers and above recommendation of proteins. The mono and polyunsaturated fats were adequate for the majority of the patients, however, the saturated fat and cholesterol were consumed in excess by a great part of the individuals. The intake of zinc was inadequate, being noticed an inadequacy of 100% in the male gender and of 84% in the female. After the treatment with rosuvastatin there was a significant reduction in the total cholesterol (TC) and LDL-c (p<0.01) and no alterations were observed in the HDL-c and triacylglycerols. It was also verified that the reduction of glycemia (p<0.05) and of hsCRP (p<0.01). The analysis did not demonstrate significant differences in the plasmatic and erythrocyte zinc concentration after the treatment. There was, after the treatment, reduction of the MT1F gene (p<0.05) without, however, occurring significant alterations in the MT2A gene. The treatment with rosuvastatin was effective in the reduction of TC and LDL-c, and promoted the reduction of inflammatory marker hsCRP. The zinc in the plasma and erythrocyte was not altered by the use of the medication and there was a reduction in the MT1F gene, possibly due to the reduction of inflammation. The majority of patients presented inadequate intake of zinc and this inadequacy did not have relation with the mineral parameters in plasma and erythrocytes or with the metallothionein gene expression

Avaliação do status antioxidante, expressão gênica e polimorfismos dos genes SOD1, SOD2 e GPx1 em crianças, adolescentes e adultos jovens com diabetes tipo 1

Studies report that the pathophysiological mechanism of diabetes complications is associated with increased production of Reactive Oxygen Species (ROS)-induced by hyperglycemia and changes in the capacity the antioxidant defense system. In this sense, the aim of this study was to evaluate changes in the capacity of antioxidant defense system, by evaluating antioxidant status, gene expression and polymorphisms in the genes of GPx1, SOD1 and SOD2 in children, adolescents and young adults with type 1 diabetes. We studied 101 individuals with type 1 diabetes (T1D) and 106 normoglycemic individuals (NG) aged between 6 and 20 years. Individuals with type 1 diabetes were evaluated as a whole group and subdivided according to glycemic control in DM1G good glycemic control and DM1P poor glycemic control. Glycemic and metabolic control was evaluate by serum glucose, glycated hemoglobin, triglycerides, total cholesterol and fractions (HDL and LDL). Renal function was assessed by measurement of serum urea and creatinine and albumin-to-creatinine ratio (ACR) in spot urine. Antioxidant status was evaluate by content of reduced glutathione (GSH) in whole blood and the activity of erythrocyte enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD). We also analyzed gene expression and gene polymorphisms of GPx1 (rs1050450), SOD1 (rs17881135) and SOD2 (rs4880) by the technique of real-time PCR (Taqman®). Most individuals with DM1 (70.3%) had poor glycemic control (glycated hemoglobin> 8%). Regarding the lipid profile, individuals with type 1 diabetes had significantly elevated total cholesterol (p <0.001) and LDL (p <0.000) compared to NG; for triglycerides only DM1NC group showed significant increase compared to NG. There was an increase in serum urea and RAC of individuals with DM1 compared to NG. Nine individuals with type 1 diabetes showed microalbuminuria (ACR> 30 mg / mg). There was a decrease in GSH content (p = 0.006) and increased erythrocyte GPx activity (p <0.001) and SOD (p <0.001) in DM1 group compared to NG. There was no significant difference in the expression of GPx1 (p = 0.305), SOD1 (.365) and SOD2 (0.385) between NG and DM1. The allele and genotype frequencies of the polymorphisms studied showed no statistically significant difference between the groups DM1 and NG. However, the GPx1 polymorphism showed the influence of erythrocyte enzyme activity. There was a decrease in GPx activity in individuals with type 1 diabetes who had a polymorphic variant T (p = 0.012). DM1 patients with the polymorphic variant G (AG + GG) for polymorphism of SOD2 (rs4880) showed an increase in the RAC (p <0.05). The combined data suggest that glucose control seems to be the predominant factor for the emergence of changes in lipid profile, renal function and antioxidant system, but the presence of the polymorphisms studied may partly contribute to the onset of complications

Algoritmos de agrupamento aplicados a dados de expressão gênica de câncer: um estudo comparativo

The use of clustering methods for the discovery of cancer subtypes has drawn a great deal of attention in the scientific community. While bioinformaticians have proposed new clustering methods that take advantage of characteristics of the gene expression data, the medical community has a preference for using classic clustering methods. There have been no studies thus far performing a large-scale evaluation of different clustering methods in this context. This work presents the first large-scale analysis of seven different clustering methods and four proximity measures for the analysis of 35 cancer gene expression data sets. Results reveal that the finite mixture of Gaussians, followed closely by k-means, exhibited the best performance in terms of recovering the true structure of the data sets. These methods also exhibited, on average, the smallest difference between the actual number of classes in the data sets and the best number of clusters as indicated by our validation criteria. Furthermore, hierarchical methods, which have been widely used by the medical community, exhibited a poorer recovery performance than that of the other methods evaluated. Moreover, as a stable basis for the assessment and comparison of different clustering methods for cancer gene expression data, this study provides a common group of data sets (benchmark data sets) to be shared among researchers and used for comparisons with new methods

Comitês de grupamento aplicados a dados de expressão gênica

The main goal of this work is to investigate the suitability of applying cluster ensemble techniques (ensembles or committees) to gene expression data. More specifically, we will develop experiments with three diferent cluster ensembles methods, which have been used in many works in literature: coassociation matrix, relabeling and voting, and ensembles based on graph partitioning. The inputs for these methods will be the partitions generated by three clustering algorithms, representing diferent paradigms: kmeans, ExpectationMaximization (EM), and hierarchical method with average linkage. These algorithms have been widely applied to gene expression data. In general, the results obtained with our experiments indicate that the cluster ensemble methods present a better performance when compared to the individual techniques. This happens mainly for the heterogeneous ensembles, that is, ensembles built with base partitions generated with diferent clustering algorithms

Expressão gênica dos REα, REβ e PR em tumores mamários de cadelas por meio do q-PCR

A expressão de receptores de estrógeno (ER) e progesterona (PR) por meio da técnica de q-PCR foi avaliada em 26 cadelas portadoras de neoplasias mamárias e cinco cadelas sem afecções mamárias (grupo controle). Os resultados mostraram que os três grupos de animais estudados - com tumor maligno ou benigno e controle - expressaram receptores de estrógeno alfa, beta e progesterona. A quantificação relativa mostrou tendência para uma expressão maior de receptores no grupo controle e menor no grupo de animais com neoplasias malignas. Além disso, observou-se expressão maior de ERα em relação ao ERβ, e as neoplasias malignas de origem mista apresentaram maiores concentrações dos receptores PR, ERα e ERβ que as neoplasias de origem epitelial.

Influência de prolongados períodos de obesidade sobre a expressão gênica miocárdica

FUNDAMENTO: Vários autores mostraram que a deterioração da função cardíaca associa-se com o grau e a duração da obesidade. Os padrões de expressão gênica após longos períodos de obesidade precisam ser estabelecidos. OBJETIVO: Este estudo testou a hipótese de que a exposição prolongada à obesidade leva à redução nos níveis de RNAm de proteínas envolvidas na homeostase do Ca2+ miocárdico. Além disso, este estudo avaliou se uma diminuição no hormônio tireoidiano causava redução na expressão de RNAm. MÉTODOS: Ratos Wistar machos de 30 dias de idade foram distribuídos em dois grupos: controle (C) e obeso (Ob). O grupo C recebeu uma dieta padrão e o grupo Ob recebeu dietas hiperlipídicas por 15, 30 e 45 semanas. A obesidade foi definida pelo índice de adiposidade. A expressão gênica foi avaliada por PCR em tempo real quantitativa. RESULTADOS: O índice de adiposidade foi maior no grupo Ob do que no C em todas as etapas. Enquanto a obesidade nas semanas 15 e 45 determinou uma redução no RNAm de Ca2+-ATPase do retículo sarcoplasmático (SERCA2a), trocador Na+/Ca2+ (NCX) e calsequestrina (CSQ), observou-se aumento da expressão do RNAm de canal de Ca2+ do tipo L, receptor de rianodina, SERCA2a, fosfolamban (PLB), NCX e CSQ após a semana 30, em comparação ao grupo C. Não houve associação significativa entre os níveis de T3 e a expressão de RNAm. CONCLUSÕES: Nossos dados indicam que a obesidade por curtos ou longos períodos de tempo pode promover alteração na expressão gênica de proteínas reguladoras da homeostase do Ca2+ sem influência do hormônio tireoidiano

Estudos de expressão gênica utilizando-se microarrays: delineamento, análise, e aplicações na pesquisa zootécnica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Expressão gênica no embrião e no endosperma micropilar de sementes de café (coffea arabica L.) durante a germinação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Expressão gênica das adesinas e fatores de virulência da fase miceliar e leveduriforme do complexo paracoccidioides e de sua interação com células epiteliais e fagócitos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação do perfil de expressão gênica de células CD34+ e células CD CD133+ isoladas de medula óssea e de sangue de cordão umbilical

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise da expressão gênica de MyoD, MRF4, miogenina e miostatina nos músculos Bíceps femoris e Gastrocnemius lateralis em duas linhagens de Gallus gallus (corte e postura)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da inflamação do tornozelo sobre as características histológicas, a expressão gênica e níveis da creatina cinase nos músculos sóleo e tibial anterior de ratos diabéticos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da obesidade sobre a expressão gênica das proteínas reguladoras do trânsito de cálcio miocárdico

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Avaliação da expressão gênica em leucócitos de eqüinos: análise pela técnica do microarray em modelo ex vivo de endotoxemia

Pós-graduação em Ciência Animal - FMVA