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1.
Diabetologia ; 66(4): 674-694, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36633628

RESUMO

AIMS/HYPOTHESIS: Genome-wide studies have uncovered multiple independent signals at the RREB1 locus associated with altered type 2 diabetes risk and related glycaemic traits. However, little is known about the function of the zinc finger transcription factor Ras-responsive element binding protein 1 (RREB1) in glucose homeostasis or how changes in its expression and/or function influence diabetes risk. METHODS: A zebrafish model lacking rreb1a and rreb1b was used to study the effect of RREB1 loss in vivo. Using transcriptomic and cellular phenotyping of a human beta cell model (EndoC-ßH1) and human induced pluripotent stem cell (hiPSC)-derived beta-like cells, we investigated how loss of RREB1 expression and activity affects pancreatic endocrine cell development and function. Ex vivo measurements of human islet function were performed in donor islets from carriers of RREB1 type 2 diabetes risk alleles. RESULTS: CRISPR/Cas9-mediated loss of rreb1a and rreb1b function in zebrafish supports an in vivo role for the transcription factor in beta cell mass, beta cell insulin expression and glucose levels. Loss of RREB1 also reduced insulin gene expression and cellular insulin content in EndoC-ßH1 cells and impaired insulin secretion under prolonged stimulation. Transcriptomic analysis of RREB1 knockdown and knockout EndoC-ßH1 cells supports RREB1 as a novel regulator of genes involved in insulin secretion. In vitro differentiation of RREB1KO/KO hiPSCs revealed dysregulation of pro-endocrine cell genes, including RFX family members, suggesting that RREB1 also regulates genes involved in endocrine cell development. Human donor islets from carriers of type 2 diabetes risk alleles in RREB1 have altered glucose-stimulated insulin secretion ex vivo, consistent with a role for RREB1 in regulating islet cell function. CONCLUSIONS/INTERPRETATION: Together, our results indicate that RREB1 regulates beta cell function by transcriptionally regulating the expression of genes involved in beta cell development and function.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Animais , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Proteínas de Ligação a DNA/metabolismo , Expressão Gênica , Glucose/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Fatores de Transcrição/genética , Peixe-Zebra/genética
3.
PLoS Genet ; 13(4): e1006528, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28448500

RESUMO

Physical activity (PA) may modify the genetic effects that give rise to increased risk of obesity. To identify adiposity loci whose effects are modified by PA, we performed genome-wide interaction meta-analyses of BMI and BMI-adjusted waist circumference and waist-hip ratio from up to 200,452 adults of European (n = 180,423) or other ancestry (n = 20,029). We standardized PA by categorizing it into a dichotomous variable where, on average, 23% of participants were categorized as inactive and 77% as physically active. While we replicate the interaction with PA for the strongest known obesity-risk locus in the FTO gene, of which the effect is attenuated by ~30% in physically active individuals compared to inactive individuals, we do not identify additional loci that are sensitive to PA. In additional genome-wide meta-analyses adjusting for PA and interaction with PA, we identify 11 novel adiposity loci, suggesting that accounting for PA or other environmental factors that contribute to variation in adiposity may facilitate gene discovery.


Assuntos
Adiposidade/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Exercício Físico , Obesidade/genética , Adiposidade/fisiologia , Índice de Massa Corporal , Epigenômica , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Obesidade/fisiopatologia , Circunferência da Cintura , Relação Cintura-Quadril
4.
Scand J Med Sci Sports ; 29(2): 213-222, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30341979

RESUMO

This study aimed to analyze the intra-individual variation in VO2max of human subjects using total-capture and free-flow indirect calorimetry. Twenty-seven men (27 ± 5 year; VO2max 49-79 mL•kg-1 •min-1 ) performed two maximal exertion tests (CPETs) on a cycle ergometer, separated by a 7 ± 2 day interval. VO2 and VCO2 were assessed using an indirect calorimeter (Omnical) with total capture of exhalation in a free-flow airstream. Thirteen subjects performed a third maximal exertion test using a breath-by-breath calorimeter (Oxycon Pro). On-site validation was deemed a requirement. For the Omnical, the mean within-subject CV for VO2max was 1.2 ± 0.9% (0.0%-4.4%) and for ergometer workload P max 1.3 ± 1.3% (0%-4.6%). VO2max values with the Oxycon Pro were significantly lower in comparison with Omnical (P < 0.001; t test) with mean 3570 vs 4061 and difference SD 361 mL•min-1 . Validation results for the Omnical with methanol combustion were -0.05 ± 0.70% (mean ± SD; n = 31) at the 225 mL•min-1 VO2 level and -0.23 ± 0.80% (n = 31) at the 150 mL•min-1 VCO2 level. Results using gas infusion were 0.04 ± 0.75% (n = 34) and -0.99 ± 1.05% (n = 24) over the respective 500-6000 mL•min-1 VO2 and VCO2 ranges. Validation results for the Oxycon Pro in breath-by-breath mode were - 2.2 ± 1.6% (n = 12) for VO2 and 5.7 ± 3.3% (n = 12) for VCO2 over the 1000-4000 mL•min-1 range. On a Visual analog scale, participants reported improved breathing using the free-flow indirect calorimetry (score 7.6 ± 1.2 vs 5.1 ± 2.7, P = 0.008). We conclude that total capturing free-flow indirect calorimetry is suitable for measuring VO2 even with the highest range. VO2max was linear with the incline in P max over the full range.


Assuntos
Calorimetria Indireta/instrumentação , Calorimetria Indireta/métodos , Consumo de Oxigênio , Adulto , Teste de Esforço , Expiração , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
6.
Hum Mol Genet ; 24(12): 3582-94, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25784503

RESUMO

Polymorphisms rs6232 and rs6234/rs6235 in PCSK1 have been associated with extreme obesity [e.g. body mass index (BMI) ≥ 40 kg/m(2)], but their contribution to common obesity (BMI ≥ 30 kg/m(2)) and BMI variation in a multi-ethnic context is unclear. To fill this gap, we collected phenotypic and genetic data in up to 331 175 individuals from diverse ethnic groups. This process involved a systematic review of the literature in PubMed, Web of Science, Embase and the NIH GWAS catalog complemented by data extraction from pre-existing GWAS or custom-arrays in consortia and single studies. We employed recently developed global meta-analytic random-effects methods to calculate summary odds ratios (OR) and 95% confidence intervals (CIs) or beta estimates and standard errors (SE) for the obesity status and BMI analyses, respectively. Significant associations were found with binary obesity status for rs6232 (OR = 1.15, 95% CI 1.06-1.24, P = 6.08 × 10(-6)) and rs6234/rs6235 (OR = 1.07, 95% CI 1.04-1.10, P = 3.00 × 10(-7)). Similarly, significant associations were found with continuous BMI for rs6232 (ß = 0.03, 95% CI 0.00-0.07; P = 0.047) and rs6234/rs6235 (ß = 0.02, 95% CI 0.00-0.03; P = 5.57 × 10(-4)). Ethnicity, age and study ascertainment significantly modulated the association of PCSK1 polymorphisms with obesity. In summary, we demonstrate evidence that common gene variation in PCSK1 contributes to BMI variation and susceptibility to common obesity in the largest known meta-analysis published to date in genetic epidemiology.


Assuntos
Índice de Massa Corporal , Predisposição Genética para Doença , Variação Genética , Obesidade/epidemiologia , Obesidade/genética , Pró-Proteína Convertase 1/genética , Alelos , Humanos , Obesidade/diagnóstico , Razão de Chances , Polimorfismo de Nucleotídeo Único
7.
PLoS Med ; 11(3): e1001618, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24642734

RESUMO

BACKGROUND: Cross-sectional studies have shown that objectively measured physical activity is associated with childhood adiposity, and a strong inverse dose-response association with body mass index (BMI) has been found. However, few studies have explored the extent to which this association reflects reverse causation. We aimed to determine whether childhood adiposity causally influences levels of physical activity using genetic variants reliably associated with adiposity to estimate causal effects. METHODS AND FINDINGS: The Avon Longitudinal Study of Parents and Children collected data on objectively assessed activity levels of 4,296 children at age 11 y with recorded BMI and genotypic data. We used 32 established genetic correlates of BMI combined in a weighted allelic score as an instrumental variable for adiposity to estimate the causal effect of adiposity on activity. In observational analysis, a 3.3 kg/m² (one standard deviation) higher BMI was associated with 22.3 (95% CI, 17.0, 27.6) movement counts/min less total physical activity (p = 1.6×10⁻¹6), 2.6 (2.1, 3.1) min/d less moderate-to-vigorous-intensity activity (p = 3.7×10⁻²9), and 3.5 (1.5, 5.5) min/d more sedentary time (p = 5.0×10⁻4). In Mendelian randomization analyses, the same difference in BMI was associated with 32.4 (0.9, 63.9) movement counts/min less total physical activity (p = 0.04) (∼5.3% of the mean counts/minute), 2.8 (0.1, 5.5) min/d less moderate-to-vigorous-intensity activity (p = 0.04), and 13.2 (1.3, 25.2) min/d more sedentary time (p = 0.03). There was no strong evidence for a difference between variable estimates from observational estimates. Similar results were obtained using fat mass index. Low power and poor instrumentation of activity limited causal analysis of the influence of physical activity on BMI. CONCLUSIONS: Our results suggest that increased adiposity causes a reduction in physical activity in children and support research into the targeting of BMI in efforts to increase childhood activity levels. Importantly, this does not exclude lower physical activity also leading to increased adiposity, i.e., bidirectional causation.


Assuntos
Adiposidade , Índice de Massa Corporal , Atividade Motora , Absorciometria de Fóton , Criança , Inglaterra , Feminino , Humanos , Estudos Longitudinais , Masculino , Análise da Randomização Mendeliana
8.
medRxiv ; 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38352379

RESUMO

Background & Aims: Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver pathology in western countries, with serious public health consequences. Efforts to identify causal genes for NAFLD have been hampered by the relative paucity of human data from gold-standard magnetic resonance quantification of hepatic fat. To overcome insufficient sample size, genome-wide association studies using NAFLD surrogate phenotypes have been used, but only a small number of loci have been identified to date. In this study, we combined GWAS of NAFLD composite surrogate phenotypes with genetic colocalization studies followed by functional in vitro screens to identify bona fide causal genes for NAFLD. Approach & Results: We used the UK Biobank to explore the associations of our novel NAFLD score, and genetic colocalization to prioritize putative causal genes for in vitro validation. We created a functional genomic framework to study NAFLD genes in vitro using CRISPRi. Our data identify VKORC1, TNKS, LYPLAL1 and GPAM as regulators of lipid accumulation in hepatocytes and suggest the involvement of VKORC1 in the lipid storage related to the development of NAFLD. Conclusions: Complementary genetic and genomic approaches are useful for the identification of NAFLD genes. Our data supports VKORC1 as a bona fide NAFLD gene. We have established a functional genomic framework to study at scale putative novel NAFLD genes from human genetic association studies.

9.
Commun Med (Lond) ; 3(1): 173, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036650

RESUMO

BACKGROUND: Whether obesity is a cause or consequence of low physical activity levels and more sedentary time has not yet been fully elucidated. Better instrumental variables and a more thorough consideration of potential confounding variables that may influence the causal inference between physical activity and obesity are needed. METHODS: Leveraging results from our recent genome-wide association study for leisure time moderate-to-vigorous intensity (MV) physical activity and screen time, we here disentangle the causal relationships between physical activity, sedentary behavior, education-defined by years of schooling-and body mass index (BMI), using multiple univariable and multivariable Mendelian Randomization (MR) approaches. RESULTS: Univariable MR analyses suggest bidirectional causal effects of physical activity and sedentary behavior with BMI. However, multivariable MR analyses that take years of schooling into account suggest that more MV physical activity causes a lower BMI, and a higher BMI causes more screen time, but not vice versa. In addition, more years of schooling causes higher levels of MV physical activity, less screen time, and lower BMI. CONCLUSIONS: In conclusion, our results highlight the beneficial effect of education on improved health and suggest that a more physically active lifestyle leads to lower BMI, while sedentary behavior is a consequence of higher BMI.


It remains unclear exactly how physical activity, sedentary behavior (usually time spent sitting or lying, often in front of a screen), and obesity influence each other, and what role education plays in this relationship. Here, we use genetic information to study this relationship. We show that if you're more physically active, you're likely to be thinner. If your weight is higher, you tend to spend more time in front of the TV or computer. Additionally, getting more years of education leads to more physical activity, less screen time, and a lower weight later in life. The take-home messages are that being more physically active can prevent obesity; watching more TV is a result but not the cause of obesity; and education stimulates a healthier lifestyle later in life. These findings may help to guide public health messaging around healthy lifestyles.

10.
Nat Genet ; 55(9): 1448-1461, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37679419

RESUMO

Conventional measurements of fasting and postprandial blood glucose levels investigated in genome-wide association studies (GWAS) cannot capture the effects of DNA variability on 'around the clock' glucoregulatory processes. Here we show that GWAS meta-analysis of glucose measurements under nonstandardized conditions (random glucose (RG)) in 476,326 individuals of diverse ancestries and without diabetes enables locus discovery and innovative pathophysiological observations. We discovered 120 RG loci represented by 150 distinct signals, including 13 with sex-dimorphic effects, two cross-ancestry and seven rare frequency signals. Of these, 44 loci are new for glycemic traits. Regulatory, glycosylation and metagenomic annotations highlight ileum and colon tissues, indicating an underappreciated role of the gastrointestinal tract in controlling blood glucose. Functional follow-up and molecular dynamics simulations of lower frequency coding variants in glucagon-like peptide-1 receptor (GLP1R), a type 2 diabetes treatment target, reveal that optimal selection of GLP-1R agonist therapy will benefit from tailored genetic stratification. We also provide evidence from Mendelian randomization that lung function is modulated by blood glucose and that pulmonary dysfunction is a diabetes complication. Our investigation yields new insights into the biology of glucose regulation, diabetes complications and pathways for treatment stratification.


Assuntos
Diabetes Mellitus Tipo 2 , Glucose , Humanos , Estudo de Associação Genômica Ampla , Glicemia/genética , Diabetes Mellitus Tipo 2/genética , Colo
11.
Nat Commun ; 13(1): 627, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110541

RESUMO

CRISPR-Cas9 genome editing has potential to cure diseases without current treatments, but therapies must be safe. Here we show that CRISPR-Cas9 editing can introduce unintended mutations in vivo, which are passed on to the next generation. By editing fertilized zebrafish eggs using four guide RNAs selected for off-target activity in vitro, followed by long-read sequencing of DNA from >1100 larvae, juvenile and adult fish across two generations, we find that structural variants (SVs), i.e., insertions and deletions ≥50 bp, represent 6% of editing outcomes in founder larvae. These SVs occur both at on-target and off-target sites. Our results also illustrate that adult founder zebrafish are mosaic in their germ cells, and that 26% of their offspring carries an off-target mutation and 9% an SV. Hence, pre-testing for off-target activity and SVs using patient material is advisable in clinical applications, to reduce the risk of unanticipated effects with potentially large implications.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Peixe-Zebra/genética , Animais , DNA , Terapia Genética , Células Germinativas , Humanos , Mutação , RNA Guia de Cinetoplastídeos/genética
12.
Nat Hum Behav ; 5(12): 1717-1730, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34211149

RESUMO

Age at first sexual intercourse and age at first birth have implications for health and evolutionary fitness. In this genome-wide association study (age at first sexual intercourse, N = 387,338; age at first birth, N = 542,901), we identify 371 single-nucleotide polymorphisms, 11 sex-specific, with a 5-6% polygenic score prediction. Heritability of age at first birth shifted from 9% [CI = 4-14%] for women born in 1940 to 22% [CI = 19-25%] for those born in 1965. Signals are driven by the genetics of reproductive biology and externalising behaviour, with key genes related to follicle stimulating hormone (FSHB), implantation (ESR1), infertility and spermatid differentiation. Our findings suggest that polycystic ovarian syndrome may lead to later age at first birth, linking with infertility. Late age at first birth is associated with parental longevity and reduced incidence of type 2 diabetes and cardiovascular disease. Higher childhood socioeconomic circumstances and those in the highest polygenic score decile (90%+) experience markedly later reproductive onset. Results are relevant for improving teenage and late-life health, understanding longevity and guiding experimentation into mechanisms of infertility.


Assuntos
Coito/fisiologia , Parto/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Fatores Etários , Feminino , Estudos de Associação Genética , Humanos , Masculino , Reprodução/genética
13.
Nat Metab ; 3(2): 228-243, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33619380

RESUMO

Obesity is a major risk factor for cardiometabolic diseases. Nevertheless, a substantial proportion of individuals with obesity do not suffer cardiometabolic comorbidities. The mechanisms that uncouple adiposity from its cardiometabolic complications are not fully understood. Here, we identify 62 loci of which the same allele is significantly associated with both higher adiposity and lower cardiometabolic risk. Functional analyses show that the 62 loci are enriched for genes expressed in adipose tissue, and for regulatory variants that influence nearby genes that affect adipocyte differentiation. Genes prioritized in each locus support a key role of fat distribution (FAM13A, IRS1 and PPARG) and adipocyte function (ALDH2, CCDC92, DNAH10, ESR1, FAM13A, MTOR, PIK3R1 and VEGFB). Several additional mechanisms are involved as well, such as insulin-glucose signalling (ADCY5, ARAP1, CREBBP, FAM13A, MTOR, PEPD, RAC1 and SH2B3), energy expenditure and fatty acid oxidation (IGF2BP2), browning of white adipose tissue (CSK, VEGFA, VEGFB and SLC22A3) and inflammation (SH2B3, DAGLB and ADCY9). Some of these genes may represent therapeutic targets to reduce cardiometabolic risk linked to excess adiposity.


Assuntos
Adiposidade/genética , Loci Gênicos/genética , Estudo de Associação Genômica Ampla , Obesidade/genética , Adipócitos/metabolismo , Adipócitos Marrons/fisiologia , Adipócitos Brancos/fisiologia , Tecido Adiposo/metabolismo , Alelos , Metabolismo Energético/fisiologia , Ácidos Graxos/metabolismo , Glucose/metabolismo , Humanos , Insulina/metabolismo , Família Multigênica/genética , Obesidade/complicações , Medição de Risco , Transdução de Sinais/fisiologia
14.
Genome Biol ; 21(1): 290, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261648

RESUMO

BACKGROUND: One ongoing concern about CRISPR-Cas9 genome editing is that unspecific guide RNA (gRNA) binding may induce off-target mutations. However, accurate prediction of CRISPR-Cas9 off-target activity is challenging. Here, we present SMRT-OTS and Nano-OTS, two novel, amplification-free, long-read sequencing protocols for detection of gRNA-driven digestion of genomic DNA by Cas9 in vitro. RESULTS: The methods are assessed using the human cell line HEK293, re-sequenced at 18x coverage using highly accurate HiFi SMRT reads. SMRT-OTS and Nano-OTS are first applied to three different gRNAs targeting HEK293 genomic DNA, resulting in a set of 55 high-confidence gRNA cleavage sites identified by both methods. Twenty-five of these sites are not reported by off-target prediction software, either because they contain four or more single nucleotide mismatches or insertion/deletion mismatches, as compared with the human reference. Additional experiments reveal that 85% of Cas9 cleavage sites are also found by other in vitro-based methods and that on- and off-target sites are detectable in gene bodies where short-reads fail to uniquely align. Even though SMRT-OTS and Nano-OTS identify several sites with previously validated off-target editing activity in cells, our own CRISPR-Cas9 editing experiments in human fibroblasts do not give rise to detectable off-target mutations at the in vitro-predicted sites. However, indel and structural variation events are enriched at the on-target sites. CONCLUSIONS: Amplification-free long-read sequencing reveals Cas9 cleavage sites in vitro that would have been difficult to predict using computational tools, including in dark genomic regions inaccessible by short-read sequencing.


Assuntos
Sequência de Bases , Sistemas CRISPR-Cas , Biologia Computacional/métodos , Edição de Genes/métodos , DNA , Variação Genética , Genômica , Células HEK293 , Humanos , Mutação , Sequenciamento por Nanoporos , RNA Guia de Cinetoplastídeos , Análise de Sequência de DNA , Software
15.
Sci Rep ; 10(1): 11831, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678143

RESUMO

A meta-analysis of genome-wide association studies (GWAS) identified eight loci that are associated with heart rate variability (HRV), but candidate genes in these loci remain uncharacterized. We developed an image- and CRISPR/Cas9-based pipeline to systematically characterize candidate genes for HRV in live zebrafish embryos. Nine zebrafish orthologues of six human candidate genes were targeted simultaneously in eggs from fish that transgenically express GFP on smooth muscle cells (Tg[acta2:GFP]), to visualize the beating heart. An automated analysis of repeated 30 s recordings of beating atria in 381 live, intact zebrafish embryos at 2 and 5 days post-fertilization highlighted genes that influence HRV (hcn4 and si:dkey-65j6.2 [KIAA1755]); heart rate (rgs6 and hcn4); and the risk of sinoatrial pauses and arrests (hcn4). Exposure to 10 or 25 µM ivabradine-an open channel blocker of HCNs-for 24 h resulted in a dose-dependent higher HRV and lower heart rate at 5 days post-fertilization. Hence, our screen confirmed the role of established genes for heart rate and rhythm (RGS6 and HCN4); showed that ivabradine reduces heart rate and increases HRV in zebrafish embryos, as it does in humans; and highlighted a novel gene that plays a role in HRV (KIAA1755).


Assuntos
Bradicardia/genética , Frequência Cardíaca/fisiologia , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Contração Miocárdica/fisiologia , Proteínas RGS/genética , Animais , Animais Geneticamente Modificados , Bradicardia/diagnóstico por imagem , Bradicardia/metabolismo , Bradicardia/fisiopatologia , Sistemas CRISPR-Cas , Fármacos Cardiovasculares/farmacologia , Embrião não Mamífero , Genes Reporter , Estudo de Associação Genômica Ampla , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/antagonistas & inibidores , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Ivabradina/farmacologia , Metanálise como Assunto , Contração Miocárdica/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Imagem Óptica/métodos , Domínios de Homologia à Plecstrina/genética , Proteínas RGS/metabolismo , Peixe-Zebra
16.
Physiol Behav ; 96(4-5): 723-8, 2009 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-19385027

RESUMO

BACKGROUND: Genetic variation in the perilipin (PLIN) gene may play a role in the etiology and treatment of obesity. OBJECTIVE: To examine different polymorphisms in the PLIN gene in relation to body-weight regulation. METHODS: 118 subjects followed a 6 wk VLCD, followed by 1 year weight maintenance. Body-weight (BW), body composition, leptin concentration, and polymorphisms of the PLIN gene: PLIN1:rs2289487, PLIN4:rs894160, PLIN6:rs1052700, PLIN5:rs2304795 and PLIN7:rs 2304796 were determined. RESULTS: BW loss during VLCD was 7.0+/-3.1 kg (p<0.05), and BW regain was 3.7+/-1.4 kg (p<0.05), including changes in body mass index (BMI), waist-circumference, body-composition and leptin concentrations (p<0.05). Linkage disequilibria were observed between PLIN1 and PLIN4: D' >0.9, r2=0.72; PLIN5 and PLIN7: D' >0.9, r2=0.85. In men, body weight, BMI, waist circumference, body fat, leptin concentrations were significantly lower for the haplotype of PLIN1 (C-alleles) and PLIN4 (A-alleles). In women weight loss and loss of fat mass were larger for the haplotype of PLIN1 (C-alleles) and PLIN4 (A-alleles). For PLIN6 genotypes body weight and body fat were lower for homozygotes of the minor allele (T/T) in the men; in the women leptin concentrations were lower. The haplotype of PLIN5 and PLIN7 consisting of A/G and G/G of PLIN5 and A/A of PLIN7 showed a reduction in FM: 5.9+/-0.6 kg vs 3.1+/-0.4 kg, % body fat: 5.5+/-0.6% vs 2.2+/-0.2%, and leptin: 20.5+/-10.8 ng/ml vs 12.9+/-6.7 ng/ml over time in the women (p<0.05). CONCLUSION: Since the haplotype of the minor alleles PLIN1-4, PLIN5-7 and PLIN6, was related to body-weight regulation at a lower level of body-weight in the men as well in the women we conclude that the PLIN1-4, 6, and 5-7 locus appears as a genetic influencer of obesity risk in humans.


Assuntos
Composição Corporal/genética , Leptina/sangue , Obesidade/genética , Fosfoproteínas/genética , Redução de Peso/genética , Adulto , Composição Corporal/fisiologia , Peso Corporal/genética , Proteínas de Transporte , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Perilipina-1 , Fatores de Risco , Redução de Peso/fisiologia
18.
J Appl Physiol (1985) ; 105(2): 561-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18511526

RESUMO

Physical exercise training is a powerful tool to maintain or improve mitochondrial density and function (mitochondrial capacity). This study aims to determine whether mitochondrial capacity is also associated with habitual physical activity in daily life (PADL). The capacity of classic markers for mitochondrial density, i.e., the capacity of citrate synthase (CS) and succinate dehydrogenase (SDH), as well the capacity of cytochrome c oxidase (COX) and beta-hydroxyacyl-CoA dehydrogenase (HAD), was determined in homogenized muscle biopsy samples obtained from the vastus lateralis muscle of nonexercising healthy young (age 20+/-2 yr) subjects (31 women, 7 men). PADL was measured during two periods of 14 days using a triaxial accelerometer for movement registration. CS, SDH, and COX were positively associated with PADL [P<0.05, R=0.36, 95% confidence interval (CI): 1.3.10(-4) to 2.2.10(-3); P<0.05, R=0.39, 95% CI: 1.1.10(-5) to 9.9.10(-5); and P<0.05, R=0.33, 95% CI: 7.5.10(-6) to 3.6.10(-4), respectively], and HAD tended to correlate positively with PADL (P=0.06, R=0.31, 95% CI: -2.2.10(-5) to 1.1.10(-3)). The population was subsequently stratified based on the intensity of the activities performed. CS was only associated with PADL in subjects spending more time on high-intensity physical activity, whereas HAD was only associated with PADL in subjects spending less time on low intensity physical activity. We are the first to report that even within the range of normal daily life activities, mitochondrial capacity is positively associated with the level of habitual physical activity in daily life. Thus an active lifestyle may help to maintain or improve mitochondrial capacity.


Assuntos
Mitocôndrias Musculares/metabolismo , Atividade Motora/fisiologia , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Adulto , Biomarcadores , Biópsia , Composição Corporal/fisiologia , Citrato (si)-Sintase/metabolismo , Transporte de Elétrons , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Humanos , Estilo de Vida , Modelos Lineares , Masculino , Mitocôndrias Musculares/enzimologia , Músculo Esquelético/metabolismo , Oxirredução , Succinato Desidrogenase/metabolismo , Telemetria
19.
Med Sci Sports Exerc ; 50(4): 863-873, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29166322

RESUMO

PURPOSE: Physical activity unquestionably maintains and improves health; however, physical activity levels globally are low and not rising despite all the resources devoted to this goal. Attention in both the research literature and the public policy domain has focused on social-behavioral factors; however, a growing body of literature suggests that biological determinants play a significant role in regulating physical activity levels. For instance, physical activity level, measured in various manners, has a genetic component in both humans and nonhuman animal models. This consensus article, developed as a result of an American College of Sports Medicine-sponsored round table, provides a brief review of the theoretical concepts and existing literature that supports a significant role of genetic and other biological factors in the regulation of physical activity. CONCLUSIONS: Future research on physical activity regulation should incorporate genetics and other biological determinants of physical activity instead of a sole reliance on social and other environmental determinants.


Assuntos
Exercício Físico , Comportamentos Relacionados com a Saúde , Biologia , Consenso , Meio Ambiente , Genética , Humanos , Sociedades Médicas , Medicina Esportiva
20.
Nat Genet ; 50(4): 524-537, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29531354

RESUMO

Stroke has multiple etiologies, but the underlying genes and pathways are largely unknown. We conducted a multiancestry genome-wide-association meta-analysis in 521,612 individuals (67,162 cases and 454,450 controls) and discovered 22 new stroke risk loci, bringing the total to 32. We further found shared genetic variation with related vascular traits, including blood pressure, cardiac traits, and venous thromboembolism, at individual loci (n = 18), and using genetic risk scores and linkage-disequilibrium-score regression. Several loci exhibited distinct association and pleiotropy patterns for etiological stroke subtypes. Eleven new susceptibility loci indicate mechanisms not previously implicated in stroke pathophysiology, with prioritization of risk variants and genes accomplished through bioinformatics analyses using extensive functional datasets. Stroke risk loci were significantly enriched in drug targets for antithrombotic therapy.


Assuntos
Acidente Vascular Cerebral/genética , Biologia Computacional , Bases de Dados Genéticas , Epigênese Genética , Feminino , Redes Reguladoras de Genes , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Mutação INDEL , Desequilíbrio de Ligação , Masculino , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Acidente Vascular Cerebral/classificação , Acidente Vascular Cerebral/fisiopatologia
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