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2.
Nat Genet ; 51(3): 452-469, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30778226

RESUMO

Body-fat distribution is a risk factor for adverse cardiovascular health consequences. We analyzed the association of body-fat distribution, assessed by waist-to-hip ratio adjusted for body mass index, with 228,985 predicted coding and splice site variants available on exome arrays in up to 344,369 individuals from five major ancestries (discovery) and 132,177 European-ancestry individuals (validation). We identified 15 common (minor allele frequency, MAF ≥5%) and nine low-frequency or rare (MAF <5%) coding novel variants. Pathway/gene set enrichment analyses identified lipid particle, adiponectin, abnormal white adipose tissue physiology and bone development and morphology as important contributors to fat distribution, while cross-trait associations highlight cardiometabolic traits. In functional follow-up analyses, specifically in Drosophila RNAi-knockdowns, we observed a significant increase in the total body triglyceride levels for two genes (DNAH10 and PLXND1). We implicate novel genes in fat distribution, stressing the importance of interrogating low-frequency and protein-coding variants.


Assuntos
Predisposição Genética para Doença/genética , Variação Genética/genética , Homeostase/genética , Lipídeos/genética , Proteínas/genética , Animais , Distribuição da Gordura Corporal/métodos , Índice de Massa Corporal , Estudos de Casos e Controles , Drosophila/genética , Exoma/genética , Feminino , Frequência do Gene/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Fatores de Risco , Relação Cintura-Quadril/métodos
3.
Biol Psychiatry ; 85(11): 946-955, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30679032

RESUMO

BACKGROUND: Smoking and alcohol use have been associated with common genetic variants in multiple loci. Rare variants within these loci hold promise in the identification of biological mechanisms in substance use. Exome arrays and genotype imputation can now efficiently genotype rare nonsynonymous and loss of function variants. Such variants are expected to have deleterious functional consequences and to contribute to disease risk. METHODS: We analyzed ∼250,000 rare variants from 16 independent studies genotyped with exome arrays and augmented this dataset with imputed data from the UK Biobank. Associations were tested for five phenotypes: cigarettes per day, pack-years, smoking initiation, age of smoking initiation, and alcoholic drinks per week. We conducted stratified heritability analyses, single-variant tests, and gene-based burden tests of nonsynonymous/loss-of-function coding variants. We performed a novel fine-mapping analysis to winnow the number of putative causal variants within associated loci. RESULTS: Meta-analytic sample sizes ranged from 152,348 to 433,216, depending on the phenotype. Rare coding variation explained 1.1% to 2.2% of phenotypic variance, reflecting 11% to 18% of the total single nucleotide polymorphism heritability of these phenotypes. We identified 171 genome-wide associated loci across all phenotypes. Fine mapping identified putative causal variants with double base-pair resolution at 24 of these loci, and between three and 10 variants for 65 loci. Twenty loci contained rare coding variants in the 95% credible intervals. CONCLUSIONS: Rare coding variation significantly contributes to the heritability of smoking and alcohol use. Fine-mapping genome-wide association study loci identifies specific variants contributing to the biological etiology of substance use behavior.

5.
Nat Genet ; 50(5): 766-767, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29549330

RESUMO

In the version of this article originally published, one of the two authors with the name Wei Zhao was omitted from the author list and the affiliations for both authors were assigned to the single Wei Zhao in the author list. In addition, the ORCID for Wei Zhao (Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA) was incorrectly assigned to author Wei Zhou. The errors have been corrected in the HTML and PDF versions of the article.

6.
Nat Genet ; 50(1): 26-41, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29273807

RESUMO

Genome-wide association studies (GWAS) have identified >250 loci for body mass index (BMI), implicating pathways related to neuronal biology. Most GWAS loci represent clusters of common, noncoding variants from which pinpointing causal genes remains challenging. Here we combined data from 718,734 individuals to discover rare and low-frequency (minor allele frequency (MAF) < 5%) coding variants associated with BMI. We identified 14 coding variants in 13 genes, of which 8 variants were in genes (ZBTB7B, ACHE, RAPGEF3, RAB21, ZFHX3, ENTPD6, ZFR2 and ZNF169) newly implicated in human obesity, 2 variants were in genes (MC4R and KSR2) previously observed to be mutated in extreme obesity and 2 variants were in GIPR. The effect sizes of rare variants are ~10 times larger than those of common variants, with the largest effect observed in carriers of an MC4R mutation introducing a stop codon (p.Tyr35Ter, MAF = 0.01%), who weighed ~7 kg more than non-carriers. Pathway analyses based on the variants associated with BMI confirm enrichment of neuronal genes and provide new evidence for adipocyte and energy expenditure biology, widening the potential of genetically supported therapeutic targets in obesity.

7.
Nature ; 542(7640): 186-190, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28146470

RESUMO

Height is a highly heritable, classic polygenic trait with approximately 700 common associated variants identified through genome-wide association studies so far. Here, we report 83 height-associated coding variants with lower minor-allele frequencies (in the range of 0.1-4.8%) and effects of up to 2 centimetres per allele (such as those in IHH, STC2, AR and CRISPLD2), greater than ten times the average effect of common variants. In functional follow-up studies, rare height-increasing alleles of STC2 (giving an increase of 1-2 centimetres per allele) compromised proteolytic inhibition of PAPP-A and increased cleavage of IGFBP-4 in vitro, resulting in higher bioavailability of insulin-like growth factors. These 83 height-associated variants overlap genes that are mutated in monogenic growth disorders and highlight new biological candidates (such as ADAMTS3, IL11RA and NOX4) and pathways (such as proteoglycan and glycosaminoglycan synthesis) involved in growth. Our results demonstrate that sufficiently large sample sizes can uncover rare and low-frequency variants of moderate-to-large effect associated with polygenic human phenotypes, and that these variants implicate relevant genes and pathways.


Assuntos
Estatura/genética , Frequência do Gene/genética , Variação Genética/genética , Proteínas ADAMTS/genética , Adulto , Alelos , Moléculas de Adesão Celular/genética , Feminino , Genoma Humano/genética , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosaminoglicanos/biossíntese , Proteínas Hedgehog/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fatores Reguladores de Interferon/genética , Subunidade alfa de Receptor de Interleucina-11/genética , Masculino , Herança Multifatorial/genética , NADPH Oxidase 4 , NADPH Oxidases/genética , Fenótipo , Proteína Plasmática A Associada à Gravidez/metabolismo , Pró-Colágeno N-Endopeptidase/genética , Proteoglicanas/biossíntese , Proteólise , Receptores Androgênicos/genética , Somatomedinas/metabolismo
8.
PLoS One ; 11(4): e0153920, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27101308

RESUMO

DNA methylation is believed to regulate gene expression during adulthood in response to the constant changes in environment. The methylome is therefore proposed to be a biomarker of health through age. ANGPTL2 is a circulating pro-inflammatory protein that increases with age and prematurely in patients with coronary artery diseases; integrating the methylation pattern of the promoter may help differentiate age- vs. disease-related change in its expression. We believe that in a pro-inflammatory environment, ANGPTL2 is differentially methylated, regulating ANGPTL2 expression. To test this hypothesis we investigated the changes in promoter methylation of ANGPTL2 gene in leukocytes from patients suffering from post-acute coronary syndrome (ACS). DNA was extracted from circulating leukocytes of post-ACS patients with cardiovascular risk factors and from healthy young and age-matched controls. Methylation sites (CpGs) found in the ANGPTL2 gene were targeted for specific DNA methylation quantification. The functionality of ANGPTL2 methylation was assessed by an in vitro luciferase assay. In post-ACS patients, C-reactive protein and ANGPTL2 circulating levels increased significantly when compared to healthy controls. Decreased methylation of specific CpGs were found in the promoter of ANGPTL2 and allowed to discriminate age vs. disease associated methylation. In vitro DNA methylation of specific CpG lead to inhibition of ANGPTL2 promoter activity. Reduced leukocyte DNA methylation in the promoter region of ANGPTL2 is associated with the pro-inflammatory environment that characterizes patients with post-ACS differently from age-matched healthy controls. Methylation of different CpGs in ANGPTL2 gene may prove to be a reliable biomarker of coronary disease.


Assuntos
Síndrome Coronariana Aguda/genética , Angiopoietinas/genética , Metilação de DNA , Leucócitos/metabolismo , Proteínas Semelhantes a Angiopoietina , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Nat Genet ; 46(6): 629-34, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24777453

RESUMO

Hematological traits are important clinical parameters. To test the effects of rare and low-frequency coding variants on hematological traits, we analyzed hemoglobin concentration, hematocrit levels, white blood cell (WBC) counts and platelet counts in 31,340 individuals genotyped on an exome array. We identified several missense variants in CXCR2 associated with reduced WBC count (gene-based P = 2.6 × 10(-13)). In a separate family-based resequencing study, we identified a CXCR2 frameshift mutation in a pedigree with congenital neutropenia that abolished ligand-induced CXCR2 signal transduction and chemotaxis. We also identified missense or splice-site variants in key hematopoiesis regulators (EPO, TFR2, HBB, TUBB1 and SH2B3) associated with blood cell traits. Finally, we were able to detect associations between a rare somatic JAK2 mutation (encoding p.Val617Phe) and platelet count (P = 3.9 × 10(-22)) as well as hemoglobin concentration (P = 0.002), hematocrit levels (P = 9.5 × 10(-7)) and WBC count (P = 3.1 × 10(-5)). In conclusion, exome arrays complement genome-wide association studies in identifying new variants that contribute to complex human traits.


Assuntos
Hemoglobinas/genética , Contagem de Leucócitos , Neutropenia/congênito , Contagem de Plaquetas , Receptores de Interleucina-8B/genética , Adulto , Idoso , Quimiotaxia , Exoma , Feminino , Mutação da Fase de Leitura , Estudo de Associação Genômica Ampla , Genótipo , Hematócrito , Hematopoese , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Neutropenia/genética , Linhagem
10.
Diabetol Metab Syndr ; 5(1): 4, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23379505

RESUMO

BACKGROUND: The dipeptidyl peptidase-4 (DPP4) enzyme is a novel adipokine potentially involved in the development of the metabolic syndrome (MetS). Previous observations demonstrated higher visceral adipose tissue (VAT) DPP4 gene expression in non-diabetic severely obese men with (MetS+) vs. without (MetS-) MetS. DPP4 mRNA abundance in VAT correlated also with CpG site methylation levels (%Meth) localized within and near its exon 2 (CpG94 to CpG102) in non-diabetic severely obese women, regardless of their MetS status. The actual study tested whether DPP4 %Meth levels in VAT are different between MetS- and MetS+ non-diabetic severely obese subjects, whether variable metabolic and plasma lipid profiles are observed between DPP4 %Meth quartiles, and whether correlation exists in DPP4 %Meth levels between VAT and white blood cells (WBCs). METHODS: DNA was extracted from the VAT of 26 men (MetS-: n=12, MetS+: n=14) and 79 women (MetS-: n=60; MetS+: n=19), as well as from WBCs in a sub-sample of 17 women (MetS-: n=9; MetS+: n=8). The %Meth levels of CpG94 to CpG102 were assessed by pyrosequencing of sodium bisulfite-treated DNA. ANOVA analyses were used to compare the %Meth of CpGs between MetS- and MetS+ groups, and to compare the metabolic phenotype and plasma lipid levels between methylation quartiles. Pearson correlation coefficient analyses were computed to test the relationship between VAT and WBCs CpG94-102 %Meth levels. RESULTS: No difference was observed in CpG94-102 %Meth levels between MetS- and MetS+ subjects in VAT (P=0.67), but individuals categorized into CpG94-102 %Meth quartiles had variable plasma total-cholesterol concentrations (P=0.04). The %Meth levels of four CpGs in VAT were significantly correlated with those observed in WBCs (r=0.55-0.59, P≤0.03). CONCLUSIONS: This study demonstrated that %Meth of CpGs localized within and near the exon 2 of the DPP4 gene in VAT are not associated with MetS status. The actual study also revealed an association between the %Meth of this locus with plasma total-cholesterol in severe obesity, which suggests a link between the DPP4 gene and plasma lipid levels.

11.
Clin Epigenetics ; 4(1): 10, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22748066

RESUMO

BACKGROUND: Epigenetic mechanisms may be involved in the regulation of genes found to be differentially expressed in the visceral adipose tissue (VAT) of severely obese subjects with (MetS+) versus without (MetS-) metabolic syndrome (MetS). Long interspersed nuclear element 1 (LINE-1) elements DNA methylation levels (%meth) in blood, a marker of global DNA methylation, have recently been associated with fasting glucose, blood lipids, heart diseases and stroke. AIM: To test whether LINE-1%meth levels in VAT are associated with MetS phenotypes and whether they can predict MetS risk in severely obese individuals. METHODS: DNA was extracted from VAT of 34 men (MetS-: n = 14, MetS+: n = 20) and 152 premenopausal women (MetS-: n = 84; MetS+: n = 68) undergoing biliopancreatic diversion for the treatment of obesity. LINE-1%meth levels were assessed by pyrosequencing of sodium bisulfite-treated DNA. RESULTS: The mean LINE-1%meth in VAT was of 75.8% (SD = 3.0%). Multiple linear regression analyses revealed that LINE-1%meth was negatively associated with fasting glucose levels (ß = -0.04; P = 0.03), diastolic blood pressure (ß = -0.65; P = 0.03) and MetS status (ß = -0.04; P = 0.004) after adjustments for the effects of age, sex, waist circumference (except for MetS status) and smoking. While dividing subjects into quartiles based on their LINE-1%meth (Q1 to Q4: lower %meth to higher %meth levels), greater risk were observed in the first (Q1: odds ratio (OR) = 4.37, P = 0.004) and the second (Q2: OR = 4.76, P = 0.002) quartiles compared to Q4 (1.00) when adjusting for age, sex and smoking. CONCLUSIONS: These results suggest that lower global DNA methylation, assessed by LINE-1 repetitive elements methylation analysis, would be associated with a greater risk for MetS in the presence of obesity.

12.
J Pediatr Gastroenterol Nutr ; 55(4): 398-402, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22487951

RESUMO

OBJECTIVES: The smallest premature neonates often receive blood transfusions early in life. Nonrestrictive transfusion policies are linked to deleterious outcomes. Exposure of total parenteral nutrition (TPN) to ambient light generates oxidation products associated with haemolysis in vitro. Shielding TPN from light limits oxidation. Our hypothesis was protecting TPN from light decreases haemolysis and therefore the need for early blood transfusions. METHODS: Comparison of haemolysis between animals fed enterally and those receiving TPN, and exploratory case-control retrospective analysis of transfusion counts in premature infants receiving light-exposed or light-protected TPN. The statistical analysis was analysis of variance and longitudinal binomial regression model adjusting for potential covariables of transfusion counts. RESULTS: In animals, TPN is associated with higher (P<0.05) haemolysis compared with enteral feeds; photoprotection induces lower peroxide load with no effect on the level of haemolysis. In premature infants, light-exposed (n=76) or light-protected (n=57) populations exhibited similar clinical characteristics. Initial haematocrit, gestational age, and index of disease severity had a significant effect on the number of transfusions. When adjusting for these covariables, photoprotection was no longer significant. CONCLUSIONS: Even though peroxides are associated in vitro with haemolysis, shielding TPN from light to reduce infused peroxides does not significantly decrease the need for early transfusions in premature infants.


Assuntos
Transfusão de Sangue , Hemólise , Recém-Nascido de Peso Extremamente Baixo ao Nascer/sangue , Recém-Nascido Prematuro/sangue , Luz , Nutrição Parenteral Total , Proteção Radiológica , Análise de Variância , Animais , Estudos de Casos e Controles , Nutrição Enteral , Feminino , Idade Gestacional , Cobaias , Hematócrito , Humanos , Lactente , Recém-Nascido , Masculino , Oxirredução , Peróxidos/sangue , Análise de Regressão , Estudos Retrospectivos , Índice de Gravidade de Doença
13.
Gene ; 499(1): 99-107, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22425646

RESUMO

There is considerable interest in defining the relationship between epigenetic variation and the risk of common complex diseases. Strategies which assist in the prioritisation of target loci that have the potential to be epigenetically regulated might provide a useful approach in identifying concrete examples of epigenotype-phenotype associations. Focusing on the postulated role of epigenetic factors in the aetiopathogenesis of obesity this report outlines an approach utilising gene expression data and a suite of bioinformatic tools to prioritise a list of target candidate genes for more detailed experimental scrutiny. Gene expression microarrays were performed using peripheral blood RNA from children aged 11-13years selected from the Newcastle Preterm Birth Growth Study which were grouped by body mass index (BMI). Genes showing ≥2.0 fold differential expression between low and high BMI groups were selected for in silico analysis. Several bioinformatic tools were used for each following step; 1) a literature search was carried out to identify whether the differentially expressed genes were associated with adiposity phenotypes. Of those obesity-candidate genes, putative epigenetically regulated promoters were identified by 2) defining the promoter regions, 3) then by selecting promoters with a CpG island (CGI), 4) and then by identifying any transcription factor binding modules covering CpG sites within the CGI. This bioinformatic processing culminated in the identification of a short list of target obesity-candidate genes putatively regulated by DNA methylation which can be taken forward for experimental analysis. The proposed workflow provides a flexible, versatile and low cost methodology for target gene prioritisation that is applicable to multiple species and disease contexts.


Assuntos
Biologia Computacional , Epigênese Genética/fisiologia , Loci Gênicos/genética , Obesidade/genética , Adolescente , Criança , Estudos de Coortes , Biologia Computacional/métodos , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Masculino , Análise em Microsséries , Especificidade por Substrato/genética
14.
Clin Sci (Lond) ; 123(2): 99-109, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22304237

RESUMO

A previous expression profiling of VAT (visceral adipose tissue) revealed that the TSLP (thymic stromal lymphopoietin) gene was less expressed in severely obese men with (n=7) compared with without (n=7) the MetS (metabolic syndrome). We hypothesized that TSLP SNPs (single nucleotide polymorphisms) are associated with TSLP gene expression in VAT and with MetS phenotypes. Following validation of lower TSLP expression (P=0.003) in VAT of severely obese men and women with (n=70) compared with without (n=60) the MetS, a detailed genetic investigation was performed at the TSLP locus by sequencing its promoter, exons and intron-exon splicing boundaries using DNA of 25 severely obese subjects. Five tagging SNPs were genotyped in the 130 subjects from the expression analysis to test whether these SNPs contributed to TSLP expression variability (ANOVAs) and then genotyped in two independent samples of severely obese men (total, n=389) and women (total, n=894). In a sex-stratified multistage experimental design, ANOVAs were performed to test whether tagging SNPs were associated with MetS components treated as continuous variables. We observed that the non-coding SNP rs2289277 was associated with TSLP mRNA abundance (P=0.04), as well as with SBP [systolic BP (blood pressure)] (P=0.004) and DBP (diastolic BP) (P=0.0003) in men when adjusting for age, waist circumference, smoking and medication treating hypertension. These novel observations suggest that TSLP expression in VAT may partly explain the inter-individual variability for metabolic impairments in the presence of obesity and that specific SNPs (rs2289277 and/or correlating SNPs) may influence TSLP gene expression as well as BP in obese men.


Assuntos
Pressão Sanguínea , Citocinas/genética , Síndrome Metabólica/etiologia , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Citocinas/fisiologia , Feminino , Genótipo , Humanos , Masculino , Síndrome Metabólica/genética , Obesidade/complicações , Fenótipo , RNA Mensageiro/análise
15.
Diabetes ; 61(2): 391-400, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22190649

RESUMO

Rapid postnatal growth is associated with increased risk of childhood adiposity. The aim of this study was to establish whether this pathway is mediated by altered DNA methylation and gene expression. Two distinct cohorts, one preterm (n=121) and one term born (n=6,990), were studied. Exploratory analyses were performed using microarrays to identify differentially expressed genes in whole blood from children defined as "slow" (n=10) compared with "rapid" (n=10) postnatal (term to 12 weeks corrected age) growers. Methylation within the identified TACSTD2 gene was measured in both cohorts, and rs61779296 genotype was determined by Pyrosequencing or imputation and analyzed in relation to body composition at 9-15 years of age. In cohort 1, TACSTD2 expression was inversely correlated with methylation (P=0.016), and both measures were associated with fat mass (expression, P=0.049; methylation, P=0.037). Although associated with gene expression (cohort 1, P=0.008) and methylation (cohort 1, P=2.98×10(-11); cohort 2, P=3.43×10(-15)), rs61779296 was not associated with postnatal growth or fat mass in either cohort following multiple regression analysis. Hence, the lack of association between fat mass and a methylation proxy SNP suggests that reverse causation or confounding may explain the initial association between fat mass and gene regulation. Noncausal methylation patterns may still be useful predictors of later adiposity.


Assuntos
Adiposidade , Antígenos de Neoplasias/genética , Composição Corporal , Moléculas de Adesão Celular/genética , Desenvolvimento Infantil , Metilação de DNA , Adolescente , Peso Corporal , Criança , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Genótipo , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
16.
Mol Genet Metab ; 105(3): 494-501, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22178353

RESUMO

Obese individuals are characterized by a chronic, low-grade inflammatory state. Increased levels of C-reactive protein (CRP), a marker of inflammation, have been observed in subjects with the metabolic syndrome. We have previously reported that genes encoding proteins involved in the anti-inflammatory and immune response are differentially expressed in visceral adipose tissue of obese men with or without the metabolic syndrome. Among these genes, the interferon-gamma-inducible protein 30 (IFI30), CD163 molecule (CD163), chemokine (C-X-C motif) ligand 9 (CXCL9) and thymic stromal lymphopoietin (TSLP), were selected for further genetic analyses. The aim of the study was to verify whether IFI30, CD163, CXCL9 and TSLP gene polymorphisms contribute to explain the inter-individual variability of the inflammatory profile of obesity assessed by plasma high-sensitivity CRP concentrations. A total of 1185 severely obese individuals were genotyped for single nucleotide polymorphisms (SNPs) covering most of the sequence-derived genetic variability at the IFI30, CD163, CXCL9 and TSLP gene loci (total of 27 SNPs). Following measurement of plasma CRP levels, subjects were divided into two groups, low vs. high using the median value of plasma CRP levels (8.31 mg/L) as a cutoff point. Genotype frequencies were compared between groups. Associations between genotypes and plasma CRP levels (continuous variable) were also tested after adjustments for age, sex, smoking and BMI. The rs11554159 and rs7125 IFI30 SNPs showed a significant difference in genotype frequencies (p<0.05) between subgroups of low vs. high plasma CRP levels (wild type homozygotes: rs11554159=47% vs. 55%, rs7125=31% vs. 24%, for low vs. high CRP groups, respectively). The association between rs11554159 and CRP levels as a continuous variable remained significant (p=0.004). Both carriers of the GA and AA genotypes demonstrated, on average, a 13% lower CRP levels in comparison with GG homozygotes. No association was observed between SNPs in the CD163, CXCL9 and TSLP genes and CRP levels. The IFI30 rs11554159 polymorphism could partially explain the inter-individual variability observed in the inflammatory profile associated with obesity.


Assuntos
Proteína C-Reativa/análise , Inflamação/genética , Obesidade Mórbida/genética , Polimorfismo de Nucleotídeo Único , Adulto , Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Biomarcadores/sangue , Índice de Massa Corporal , Proteína C-Reativa/imunologia , Quimiocina CXCL9/genética , Citocinas/genética , Feminino , Genótipo , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Receptores de Superfície Celular/genética , Análise de Sequência de DNA
17.
Obesity (Silver Spring) ; 19(2): 388-95, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20847730

RESUMO

Severely obese subjects with the metabolic syndrome (MS) have higher dipeptidyl peptidase-4 (DPP4) expression in their visceral adipose tissue (VAT) compared to obese individuals without MS. We tested the hypothesis that methylation level of CpG sites in the DPP4 promoter CpG island in VAT was genotype-dependent and associated with DPP4 mRNA abundance and MS-related phenotypes. The VAT DNA was extracted in 92 severely obese premenopausal women undergoing biliopancreatic derivation for the treatment of obesity. Women were nondiabetic and none of them used medication to treat MS features. Cytosine methylation rates (%) of 102 CpG sites in the DPP4 CpG island were assessed by pyrosequencing of sodium bisulfite-treated DNA. Methylation rates were >10% for CpG sites 94-102. Their mean methylation rate (%Meth(94-102)) was different between genotypes for DPP4 polymorphisms rs13015258 (P = 0.001), rs17848915 (P = 0.0004), and c.1926 G>A (P = 0.001). The %Meth(94-102) correlated negatively with DPP4 mRNA abundance (r = -0.25, P < 0.05) and positively with plasma high-density lipoprotein (HDL) cholesterol concentrations (r = 0.22, P < 0.05), whereas DPP4 mRNA abundance correlated positively with plasma total-/HDL-cholesterol ratio (r = 0.25; P < 0.05). In the VAT of nondiabetic severely obese women, genotype-dependent methylation levels of specific CpG sites in the DPP4 promoter CpG island were associated with DPP4 gene expression and variability in the plasma lipid profile. Higher DPP4 gene expression in VAT and its relationship with the plasma lipid profile may be explained by actually unknown DPP4 biological effect or, to another extent, may also be a marker of VAT inflammation known to be associated with metabolic disturbances.


Assuntos
Metilação de DNA , Dipeptidil Peptidase 4/genética , Gordura Intra-Abdominal/metabolismo , Síndrome Metabólica/genética , Obesidade Mórbida/genética , Omento/metabolismo , Adulto , Desvio Biliopancreático , Feminino , Expressão Gênica , Genótipo , Humanos , Gordura Intra-Abdominal/enzimologia , Lipídeos/sangue , Síndrome Metabólica/enzimologia , Síndrome Metabólica/metabolismo , Obesidade Mórbida/enzimologia , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Polimorfismo Genético , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
18.
Free Radic Biol Med ; 47(3): 275-82, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19409486

RESUMO

Newborn infants are at risk for oxidative stress leading to metabolic syndrome features. Oxidative stress can be induced by oxidant load such as oxygen supplementation, peroxides from intravenous nutrition, or low antioxidant defenses. We hypothesize that a modulation of antioxidant defenses during the neonatal period, without external oxidant challenge, will have a long-term influence on energy metabolism. Guinea pigs were fed between their third and their seventh day of life a regular chow leading to "mature" antioxidant defenses or a deficient chow leading to lower antioxidant defenses. Between weeks 1 and 14, the animals were fed regular chow. The hepatic oxidized redox status of glutathione associated with the deficient diet (-221 +/- 2 vs -228 +/- 1 mV, p < 0.01) was maintained until 14 weeks. At 13-14 weeks, animals fed the deficient diet presented lower plasma TG (479 +/- 57 vs 853 +/- 32 microM, p < 0.01), lower blood glucose (5.8 +/- 0.3 vs 6.9 +/- 0.3 mM, p < 0.05), and better tolerance to glucose (p < 0.05). Blood glucose correlated negatively with the redox status (r2 = 0.47, p < 0.01). Low antioxidant defenses during the neonatal period induce a better energy substrate profile associated with an oxidized redox status later in life. These findings suggest being aware of negative consequences when adopting "aggressive" antioxidant therapies in newborn infants.


Assuntos
Animais Recém-Nascidos , Alimentos Formulados , Glucose/metabolismo , Fígado/fisiologia , Síndrome Metabólica/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Antioxidantes/metabolismo , Dietoterapia/tendências , Dinoprosta/análogos & derivados , Dinoprosta/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Teste de Tolerância a Glucose , Glutationa/metabolismo , Cobaias , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo dos Lipídeos , Síndrome Metabólica/sangue , Síndrome Metabólica/dietoterapia , Síndrome Metabólica/genética , Oxirredução , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fatores de Tempo , Triglicerídeos/sangue
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