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1.
Wiad Lek ; 73(8): 1637-1640, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33055325

RESUMO

OBJECTIVE: The aim: To examine the association between polymorphisms of the IL-6 gene promoter and HF in patients with CAD and obesity. PATIENTS AND METHODS: Material and methods: 222 patients with coronary artery disease and obesity were identified. Comparison group consisted of 115 patients with coronary artery disease with normal body weight. The groups were comparable in age and sex. The exclusion group consisted of patients with severe concomitant diseases of the respiratory and digestive organs, kidneys and people with cancer. One single nucleotide polymorphisms in the interleukin-6 promoter region was analyzed. Odds ratio (OR) and 95 % confident interval (95 % CI) were calculated. RESULTS: Results: The combined course of coronary artery disease and obesity was characterized by the detection of allele C in 62 patients (27.93 %), allele G - in 160 patients (72.07 %), and genotypes CC, CG and GG - at 24 (10.81 %), 67 (30.18 %) and 131 (59.01 %) patients respectively. The results showed that the -174G allele and GG genotype in patients with coronary artery disease and obesity were associated with heart failure (OR = 2.55, 95% CI = [1.72-3.79], χ2 = 22.8; p<0.05) and (OR = 11.95, 95% CI = [3.41-41.91], χ2 = 22.5; p<0.05), whereas allele C-174 was associated with a decrease in the risk of heart failure (OR = 0.39, 95% CI = [0.26-0.58 ], χ2 = 22.75, p<0.05). CONCLUSION: Conclusions: The obtained results testify that the -174G>C polymorphism in the interleukin-6 gene is significantly associated with increased risk of heart failure in patients with coronary artery disease and obesity.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Interleucina-6 , Obesidade , Alelos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/genética , Feminino , Insuficiência Cardíaca/genética , Humanos , Interleucina-6/genética , Masculino , Obesidade/complicações , Obesidade/genética
2.
Anticancer Res ; 40(10): 5445-5456, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988866

RESUMO

BACKGROUND/AIM: Dietary interventions like time-restricted feeding (TRF) show promising anti-cancer properties. We examined whether therapeutic TRF alone or combined with immunotherapy would diminish renal tumor growth in mice of varying body weights. MATERIALS AND METHODS: Young (7 week) chow-fed or older (27 week) high-fat diet (HFD)-fed BALB/c mice were orthotopically injected with renal tumor cells expressing luciferase. After tumor establishment, mice were randomized to ad libitum feeding or TRF +/- anti-CTLA-4. Body composition, tumor viability and growth, and immune responses were quantified. RESULTS: TRF alone reduced renal tumor bioluminescence in older HFD-fed, but not young chow-fed mice. In the latter, TRF mitigated tumor-induced loss of lean- and fat-mass. However, TRF did not alter excised renal tumor weights or intratumoral immune responses and failed to improve anti-CTLA-4 outcomes in any mice. CONCLUSION: Therapeutic TRF exhibits modest anti-cancer properties but fails to improve anti-CTLA-4 immune checkpoint blockade in murine renal cancer.


Assuntos
Jejum , Neoplasias Renais/tratamento farmacológico , Obesidade/tratamento farmacológico , Animais , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Modelos Animais de Doenças , Ingestão de Alimentos/fisiologia , Humanos , Imunoterapia/efeitos adversos , Neoplasias Renais/complicações , Neoplasias Renais/genética , Neoplasias Renais/patologia , Camundongos , Obesidade/complicações , Obesidade/genética
3.
PLoS One ; 15(8): e0237708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817646

RESUMO

Parental high-fat diet (HFD) programs for obesity and hypertension in female offspring in rats, but it is unknown how the pregnancies of these offspring are impacted. Therefore, the hypothesis was tested that parental HFD exaggerates obesity and hypertension during pregnancy of the offspring. Wistar Hannover rat dams (the parental, P generation) were maintained on normal-fat diet (NFD) or HFD from weaning and were kept on respective diets through pregnancy and lactation. Their offspring (the first filial, F1 generation) were weaned onto the same diet as the P generation, or they were changed to the other diet to determine if combined HFD in the P and F1 generations exaggerates body weight and blood pressure levels during pregnancy in these offspring. This diet paradigm resulted in the following groups of pregnant F1 offspring: P-NFD/F1-NFD, P-HFD/F1-NFD, P-NFD/F1-HFD, and P-HFD/F1-HFD. Maternal body and adipose tissue weights were greatest in the P-HFD/F1-HFD group compared to the other 3 groups by the end of pregnancy. Plasma leptin and conscious mean arterial blood pressure were not significantly different between any group, although there was a main effect for increased blood pressure in the F1-HFD groups. Circulating levels of the antihypertensive pregnancy factor, placental growth factor (PlGF), were assessed. Although average PlGF levels were similar among all groups, correlative studies revealed that lower levels of PlGF were associated with higher blood pressure only in the P-HFD/F1-HFD group. In summary, HFD feeding from the P generation exaggerated HFD-induced body and adipose tissue weights in the pregnant offspring.


Assuntos
Hipertensão/sangue , Leptina/sangue , Obesidade/sangue , Fator de Crescimento Placentário/sangue , Efeitos Tardios da Exposição Pré-Natal/sangue , Adiposidade/genética , Animais , Pressão Sanguínea/genética , Peso Corporal/genética , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Humanos , Hipertensão/genética , Hipertensão/fisiopatologia , Masculino , Herança Materna/genética , Obesidade/genética , Obesidade/fisiopatologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos , Desmame
4.
Nat Commun ; 11(1): 3794, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732906

RESUMO

Defective rhythmic metabolism is associated with high-fat high-caloric diet (HFD) feeding, ageing and obesity; however, the neural basis underlying HFD effects on diurnal metabolism remains elusive. Here we show that deletion of BMAL1, a core clock gene, in paraventricular hypothalamic (PVH) neurons reduces diurnal rhythmicity in metabolism, causes obesity and diminishes PVH neuron activation in response to fast-refeeding. Animal models mimicking deficiency in PVH neuron responsiveness, achieved through clamping PVH neuron activity at high or low levels, both show obesity and reduced diurnal rhythmicity in metabolism. Interestingly, the PVH exhibits BMAL1-controlled rhythmic expression of GABA-A receptor γ2 subunit, and dampening rhythmicity of GABAergic input to the PVH reduces diurnal rhythmicity in metabolism and causes obesity. Finally, BMAL1 deletion blunts PVH neuron responses to external stressors, an effect mimicked by HFD feeding. Thus, BMAL1-driven PVH neuron responsiveness in dynamic activity changes involving rhythmic GABAergic neurotransmission mediates diurnal rhythmicity in metabolism and is implicated in diet-induced obesity.


Assuntos
Fatores de Transcrição ARNTL/genética , Ritmo Circadiano/fisiologia , Obesidade/patologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Receptores de GABA-A/metabolismo , Animais , Ritmo Circadiano/genética , Dieta Hiperlipídica , Metabolismo Energético/fisiologia , Comportamento Alimentar/fisiologia , Camundongos , Camundongos Knockout , Neurônios/fisiologia , Obesidade/genética , Núcleo Hipotalâmico Paraventricular/citologia
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(7): 1097-1102, 2020 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-32741178

RESUMO

Objective: The aim of this study is to investigate the relationship between fat mass and obesity associated (FTO) gene polymorphism and the risk of gestational diabetes mellitus (GDM), and provide clues and basis for the study of GDM mechanism. Methods: The case group of GDM pregnant women who delivered at the First Affiliated Hospital of Shanxi Medical University from March 1, 2012 to July 30, 2014 were selected, and matched the control group among non-GDM pregnant women by age, gestational age and residential address, and 324 cases and 318 controls were finally included. DNA was extracted and genotyped, and min P test and unconditional logistic regression model were used to estimate the relationship between FTO gene polymorphism and GDM. Results: At gene level, we did not find the association between FTO and the risk of GDM (P>0.05). After adjusted for family history of diabetes, pre-pregnancy body mass index and multiple comparisons using false discovery rate method, unconditional logistic regression analysis showed that pregnant women who carried the rs11075995 TT genotype (OR=0.59, 95%CI: 0.35-0.89), rs3826169 GG genotype (OR=0.59, 95%CI: 0.35-0.88), and rs74245270 GA genotype (OR=0.69, 95%CI: 0.49-0.98), GA or AA genotype(OR=0.70, 95%CI: 0.50-0.97) had reduced risk of GDM. However, pregnant women who carried the rs74018601 GA genotype (OR=1.51, 95%CI: 1.07-2.12), GA or AA genotype (OR=1.46, 95%CI: 1.06-2.02), rs7205009 AA genotype (OR=1.83, 95%CI: 1.18-2.86), GA or AA genotype (OR=1.53, 95%CI: 1.08-2.19), and rs9888758 AG genotype (OR=1.43, 95%CI: 1.02-2.00) had elevated risk of GDM. Conclusion: The polymorphisms of FTO gene rs11075995,rs3826169, rs74245270, rs74018601, rs7205009 and rs9888758 were associated with the risk of GDM.


Assuntos
Tecido Adiposo , Diabetes Gestacional/epidemiologia , Obesidade/genética , Polimorfismo Genético , Estudos de Casos e Controles , China/epidemiologia , Feminino , Genótipo , Humanos , Gravidez , Fatores de Risco
7.
PLoS Comput Biol ; 16(8): e1008044, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797044

RESUMO

Genetic studies have recently highlighted the importance of fat distribution, as well as overall adiposity, in the pathogenesis of obesity-associated diseases. Using a large study (n = 1,288) from 4 independent cohorts, we aimed to investigate the relationship between mean adipocyte area and obesity-related traits, and identify genetic factors associated with adipocyte cell size. To perform the first large-scale study of automatic adipocyte phenotyping using both histological and genetic data, we developed a deep learning-based method, the Adipocyte U-Net, to rapidly derive mean adipocyte area estimates from histology images. We validate our method using three state-of-the-art approaches; CellProfiler, Adiposoft and floating adipocytes fractions, all run blindly on two external cohorts. We observe high concordance between our method and the state-of-the-art approaches (Adipocyte U-net vs. CellProfiler: R2visceral = 0.94, P < 2.2 × 10-16, R2subcutaneous = 0.91, P < 2.2 × 10-16), and faster run times (10,000 images: 6mins vs 3.5hrs). We applied the Adipocyte U-Net to 4 cohorts with histology, genetic, and phenotypic data (total N = 820). After meta-analysis, we found that mean adipocyte area positively correlated with body mass index (BMI) (Psubq = 8.13 × 10-69, ßsubq = 0.45; Pvisc = 2.5 × 10-55, ßvisc = 0.49; average R2 across cohorts = 0.49) and that adipocytes in subcutaneous depots are larger than their visceral counterparts (Pmeta = 9.8 × 10-7). Lastly, we performed the largest GWAS and subsequent meta-analysis of mean adipocyte area and intra-individual adipocyte variation (N = 820). Despite having twice the number of samples than any similar study, we found no genome-wide significant associations, suggesting that larger sample sizes and a homogenous collection of adipose tissue are likely needed to identify robust genetic associations.


Assuntos
Adipócitos , Aprendizado de Máquina , Obesidade , Adipócitos/classificação , Adipócitos/citologia , Tecido Adiposo/fisiologia , Adulto , Índice de Massa Corporal , Tamanho Celular , Biologia Computacional/métodos , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Obesidade/epidemiologia , Obesidade/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
9.
Proc Natl Acad Sci U S A ; 117(33): 20149-20158, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747560

RESUMO

The C2 domain containing protein extended synaptotagmin (E-Syt) plays important roles in both lipid homeostasis and the intracellular signaling; however, its role in physiology remains largely unknown. Here, we show that hypothalamic E-Syt3 plays a critical role in diet-induced obesity (DIO). E-Syt3 is characteristically expressed in the hypothalamic nuclei. Whole-body or proopiomelanocortin (POMC) neuron-specific ablation of E-Syt3 ameliorated DIO and related comorbidities, including glucose intolerance and dyslipidemia. Conversely, overexpression of E-Syt3 in the arcuate nucleus moderately promoted food intake and impaired energy expenditure, leading to increased weight gain. Mechanistically, E-Syt3 ablation led to increased processing of POMC to α-melanocyte-stimulating hormone (α-MSH), increased activities of protein kinase C and activator protein-1, and enhanced expression of prohormone convertases. These findings reveal a previously unappreciated role for hypothalamic E-Syt3 in DIO and related metabolic disorders.


Assuntos
Regulação da Expressão Gênica/fisiologia , Obesidade/induzido quimicamente , Obesidade/genética , Sinaptotagminas/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Predisposição Genética para Doença , Hipotálamo/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Pró-Proteína Convertase 1/genética , Pró-Proteína Convertase 1/metabolismo , Pró-Proteína Convertase 2/genética , Pró-Proteína Convertase 2/metabolismo , Sinaptotagminas/genética
10.
Arterioscler Thromb Vasc Biol ; 40(9): 2227-2243, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32640901

RESUMO

OBJECTIVE: Perivascular adipose tissue (PVAT) surrounding arteries supports healthy vascular function. During obesity, PVAT loses its vasoprotective effect. We study pathological conversion of PVAT, which involves molecular changes in protein profiles and functional changes in adipocytes. Approach and Results: C57BL6/J mice were fed a 60% high-fat diet for 12 weeks or a cardioprotective 30% calorie-restricted diet for 5 weeks. Proteomic analysis identified PVAT as a molecularly distinct adipose depot, and novel markers for thermogenic adipocytes, such as GRP75 (stress-70 protein, mitochondrial), were identified. High-fat diet increased the similarity of protein signatures in PVAT and brown adipose, suggesting activation of a conserved whitening pathway. The whitening phenotype was characterized by suppression of UCP1 (uncoupling protein 1) and increased lipid deposition, leptin, and inflammation, and specifically in PVAT, elevated Notch signaling. Conversely, PVAT from calorie-restricted mice had decreased Notch signaling and less lipid. Using the Adipoq-Cre strain, we constitutively activated Notch1 signaling in adipocytes, which phenocopied the changes in PVAT caused by a high-fat diet, even on a standard diet. Preadipocytes from mouse PVAT expressed Sca1, CD140a, Notch1, and Notch2, but not CD105, showing differences compared with preadipocytes from other depots. Inhibition of Notch signaling during differentiation of PVAT-derived preadipocytes reduced lipid deposition and adipocyte marker expression. CONCLUSIONS: PVAT shares features with other adipose depots, but has a unique protein signature that is regulated by dietary stress. Increased Notch signaling in PVAT is sufficient to initiate the pathological conversion of PVAT by promoting adipogenesis and lipid accumulation and may thus prime the microenvironment for vascular disease.


Assuntos
Adipócitos Brancos/metabolismo , Adipogenia , Tecido Adiposo Branco/metabolismo , Lipogênese , Obesidade/metabolismo , Receptores Notch/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo Branco/patologia , Adiposidade , Animais , Ataxina-1/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Restrição Calórica , Dieta Hiperlipídica , Modelos Animais de Doenças , Endoglina/metabolismo , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/genética , Obesidade/patologia , Fenótipo , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Proteômica , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptor Notch2/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores Notch/genética , Transdução de Sinais
11.
Arterioscler Thromb Vasc Biol ; 40(9): e240-e255, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32698687

RESUMO

OBJECTIVE: To determine if endothelial dysfunction in a mouse model of diet-induced obesity and in obese humans is mediated by the suppression of endothelial Kir (inwardly rectifying K+) channels. Approach and Results: Endothelial dysfunction, observed as reduced dilations to flow, occurred after feeding mice a high-fat, Western diet for 8 weeks. The functional downregulation of endothelial Kir2.1 using dominant-negative Kir2.1 construct resulted in substantial reductions in the response to flow in mesenteric arteries of lean mice, whereas no effect was observed in arteries of obese mice. Overexpressing wild-type-Kir2.1 in endothelium of arteries from obese mice resulted in full recovery of the flow response. Exposing freshly isolated endothelial cells to fluid shear during patch-clamp electrophysiology revealed that the flow-sensitivity of Kir was virtually abolished in cells from obese mice. Atomic force microscopy revealed that the endothelial glycocalyx was stiffer and the thickness of the glycocalyx layer reduced in arteries from obese mice. We also identified that the length of the glycocalyx is critical to the flow-activation of Kir. Overexpressing Kir2.1 in endothelium of arteries from obese mice restored flow- and heparanase-sensitivity, indicating an important role for heparan sulfates in the flow-activation of Kir. Furthermore, the Kir2.1-dependent component of flow-induced vasodilation was lost in the endothelium of resistance arteries of obese humans obtained from biopsies collected during bariatric surgery. CONCLUSIONS: We conclude that obesity-induced impairment of flow-induced vasodilation is attributed to the loss of flow-sensitivity of endothelial Kir channels and propose that the latter is mediated by the biophysical alterations of the glycocalyx.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Glicocálix/metabolismo , Artérias Mesentéricas/metabolismo , Obesidade/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Vasodilatação , Adulto , Animais , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Feminino , Heparitina Sulfato/metabolismo , Humanos , Masculino , Mecanotransdução Celular , Potenciais da Membrana , Artérias Mesentéricas/fisiopatologia , Camundongos , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/fisiopatologia , Canais de Potássio Corretores do Fluxo de Internalização/genética , Fluxo Sanguíneo Regional
12.
Proc Natl Acad Sci U S A ; 117(28): 16616-16625, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601203

RESUMO

Enhanced inflammation is believed to contribute to overnutrition-induced metabolic disturbance. Nutrient flux has also been shown to be essential for immune cell activation. Here, we report an unexpected role of nutrient-sensing O-linked ß-N-acetylglucosamine (O-GlcNAc) signaling in suppressing macrophage proinflammatory activation and preventing diet-induced metabolic dysfunction. Overnutrition stimulates an increase in O-GlcNAc signaling in macrophages. O-GlcNAc signaling is down-regulated during macrophage proinflammatory activation. Suppressing O-GlcNAc signaling by O-GlcNAc transferase (OGT) knockout enhances macrophage proinflammatory polarization, promotes adipose tissue inflammation and lipolysis, increases lipid accumulation in peripheral tissues, and exacerbates tissue-specific and whole-body insulin resistance in high-fat-diet-induced obese mice. OGT inhibits macrophage proinflammatory activation by catalyzing ribosomal protein S6 kinase beta-1 (S6K1) O-GlcNAcylation and suppressing S6K1 phosphorylation and mTORC1 signaling. These findings thus identify macrophage O-GlcNAc signaling as a homeostatic mechanism maintaining whole-body metabolism under overnutrition.


Assuntos
Macrófagos/imunologia , N-Acetilglucosaminiltransferases/imunologia , Obesidade/imunologia , Proteínas Quinases S6 Ribossômicas 90-kDa/imunologia , Acetilglucosamina/imunologia , Tecido Adiposo/imunologia , Animais , Humanos , Ativação de Macrófagos , Macrófagos/enzimologia , Camundongos , Camundongos Knockout , N-Acetilglucosaminiltransferases/genética , Obesidade/enzimologia , Obesidade/genética , Obesidade/metabolismo , Fosforilação , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Transdução de Sinais
13.
Vasc Health Risk Manag ; 16: 249-256, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612360

RESUMO

Background: The role of metabolic states in cardiovascular risks among individuals with varying degrees of obesity is unknown. The study aimed to compare cardiometabolic index (CMI), atherogenic index of plasma (AIP), lipid accumulation product (LAP) and novel anthropometric indices in metabolic and non-metabolically obese individual with regard to the role of FTO gene in Iranian adults. Methods: In total, 165 individuals were recruited into this cross-sectional study. Individuals grouped into four groups: metabolic healthy normal-weight (MHNW) individuals, metabolically unhealthy normal-weight (MUNW) individuals, metabolically healthy obese (MHO) individuals and metabolic unhealthy obese (MUO) individuals. The dietary intake was evaluated by food frequency questionnaire (FFQ). The cardiovascular indices (CMI, AIP and LAP) were calculated. A variety of anthropometric indices were calculated, including body adiposity Index (BAI), weight-adjusted-waist index (WWI), A body shape index (ABSI) and waist-height ratio (WHR). The genotypes of FTO-rs9939609 subjects were detected by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The individuals with metabolically unhealthy phenotypes (MUO, MUNW) have higher levels of triglyceride and cardiovascular indices (AIP, LAP and CMI) than the individuals with metabolic healthy phenotypes (MHO, MHNW). With a similar degree of obesity, the anthropometric indices (BAI, WWI and WHR) levels were higher in metabolic unhealthy groups than metabolically healthy groups. The highest frequency of obesity-risk allele AA of FTO gene was observed in MUO, MHO, MUNW and MHNW, respectively. Conclusion: Normal-weight individuals with metabolic unhealthy status are at higher risk for cardiovascular diseases than obese individuals with metabolically healthy status. The genotype frequencies of obesity-risk allele AA of FTO gene were higher in obesity phenotypes than metabolic phenotypes.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Doenças Cardiovasculares/genética , Metabolismo Energético/genética , Síndrome Metabólica/genética , Obesidade Metabolicamente Benigna/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Antropometria , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Estudos Transversais , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Lipídeos/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/diagnóstico , Obesidade Metabolicamente Benigna/sangue , Obesidade Metabolicamente Benigna/diagnóstico , Fenótipo , Medição de Risco , Fatores de Risco , Adulto Jovem
14.
PLoS Med ; 17(7): e1003196, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32692746

RESUMO

BACKGROUND: Melanocortin 4 receptor (MC4R) deficiency, caused by mutations in MC4R, is the most common cause of monogenic forms of obesity. However, these mutations have often been identified in small-scale, case-focused studies. Here, we assess the penetrance of previously reported MC4R mutations at a population level. Furthermore, we examine why some carriers of pathogenic mutations remain of normal weight, to gain insight into the mechanisms that control body weight. METHODS AND FINDINGS: We identified 59 known obesity-increasing mutations in MC4R from the Human Gene Mutation Database (HGMD) and Clinvar. We assessed their penetrance and effect on obesity (body mass index [BMI] ≥ 30 kg/m2) in >450,000 individuals (age 40-69 years) of the UK Biobank, a population-based cohort study. Of these 59 mutations, only 11 had moderate-to-high penetrance and increased the odds of obesity by more than 2-fold. We subsequently focused on these 11 mutations and examined differences between carriers of normal weight and carriers with obesity. Twenty-eight of the 182 carriers of these 11 mutations were of normal weight. Body composition of carriers of normal weight was similar to noncarriers of normal weight, whereas among individuals with obesity, carriers had a somewhat higher BMI than noncarriers (1.44 ± 0.07 standard deviation scores [SDSs] ± standard error [SE] versus 1.29 ± 0.001, P = 0.03), because of greater lean mass (1.44 ± 0.09 versus 1.15 ± 0.002, P = 0.002). Carriers of normal weight more often reported that, already at age 10 years, their body size was below average or average (72%) compared with carriers with obesity (48%) (P = 0.01). To assess the polygenic contribution to body weight in carriers of normal weight and carriers with obesity, we calculated a genome-wide polygenic risk score for BMI (PRSBMI). The PRSBMI of carriers of normal weight (PRSBMI = -0.64 ± 0.18) was significantly lower than of carriers with obesity (0.40 ± 0.11; P = 1.7 × 10-6), and tended to be lower than that of noncarriers of normal weight (-0.29 ± 0.003; P = 0.05). Among carriers, those with a low PRSBMI (bottom quartile) have an approximately 5-kg/m2 lower BMI (approximately 14 kg of body weight for a 1.7-m-tall person) than those with a high PRS (top quartile). Because the UK Biobank population is healthier than the general population in the United Kingdom, penetrance may have been somewhat underestimated. CONCLUSIONS: We showed that large-scale data are needed to validate the impact of mutations observed in small-scale and case-focused studies. Furthermore, we observed that despite the key role of MC4R in obesity, the effects of pathogenic MC4R mutations may be countered, at least in part, by a low polygenic risk potentially representing other innate mechanisms implicated in body weight regulation.


Assuntos
Mutação , Obesidade/genética , Receptor Tipo 4 de Melanocortina/genética , Adulto , Idoso , Bancos de Espécimes Biológicos , Composição Corporal/genética , Índice de Massa Corporal , Peso Corporal/genética , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Penetrância , Reino Unido
15.
PLoS Med ; 17(7): e1003219, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32692747

RESUMO

BACKGROUND: The influence of genetic risk for obesity on food choice behaviors is unknown and may be in the causal pathway between genetic risk and weight gain. The aim of this study was to examine associations between genetic risk for obesity and food choice behaviors using objectively assessed workplace food purchases. METHODS AND FINDINGS: This study is a secondary analysis of baseline data collected prior to the start of the "ChooseWell 365" health-promotion intervention randomized control trial. Participants were employees of a large hospital in Boston, MA, who enrolled in the study between September 2016 and February 2018. Cafeteria sales data, collected retrospectively for 3 months prior to enrollment, were used to track the quantity (number of items per 3 months) and timing (median time of day) of purchases, and participant surveys provided self-reported behaviors, including skipping meals and preparing meals at home. A previously validated Healthy Purchasing Score was calculated using the cafeteria traffic-light labeling system (i.e., green = healthy, yellow = less healthy, red = unhealthy) to estimate the healthfulness (quality) of employees' purchases (range, 0%-100% healthy). DNA was extracted and genotyped from blood samples. A body mass index (BMI) genome-wide polygenic score (BMIGPS) was generated by summing BMI-increasing risk alleles across the genome. Additionally, 3 polygenic risk scores (PRSs) were generated with 97 BMI variants previously identified at the genome-wide significance level (P < 5 × 10-8): (1) BMI97 (97 loci), (2) BMICNS (54 loci near genes related to central nervous system [CNS]), and (3) BMInon-CNS (43 loci not related to CNS). Multivariable linear and logistic regression tested associations of genetic risk score quartiles with workplace purchases, adjusted for age, sex, seasonality, and population structure. Associations were considered significant at P < 0.05. In 397 participants, mean age was 44.9 years, and 80.9% were female. Higher genetic risk scores were associated with higher BMI. The highest quartile of BMIGPS was associated with lower Healthy Purchasing Score (-4.8 percentage points [95% CI -8.6 to -1.0]; P = 0.02), higher quantity of food purchases (14.4 more items [95% CI -0.1 to 29.0]; P = 0.03), later time of breakfast purchases (15.0 minutes later [95% CI 1.5-28.5]; P = 0.03), and lower likelihood of preparing dinner at home (Q4 odds ratio [OR] = 0.3 [95% CI 0.1-0.9]; P = 0.03) relative to the lowest BMIGPS quartile. Compared with the lowest quartile, the highest BMICNS quartile was associated with fewer items purchased (P = 0.04), and the highest BMInon-CNS quartile was associated with purchasing breakfast at a later time (P = 0.01), skipping breakfast (P = 0.03), and not preparing breakfast (P = 0.04) or lunch (P = 0.01) at home. A limitation of this study is our data come from a relatively small sample of healthy working adults of European ancestry who volunteered to enroll in a health-promotion study, which may limit generalizability. CONCLUSIONS: In this study, genetic risk for obesity was associated with the quality, quantity, and timing of objectively measured workplace food purchases. These findings suggest that genetic risk for obesity may influence eating behaviors that contribute to weight and could be targeted in personalized workplace wellness programs in the future. TRIAL REGISTRATION: Clinicaltrials.gov NCT02660086.


Assuntos
Preferências Alimentares , Obesidade/etiologia , Obesidade/genética , Adulto , Índice de Massa Corporal , Boston , Comportamento do Consumidor , Feminino , Qualidade dos Alimentos , Predisposição Genética para Doença , Promoção da Saúde/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Local de Trabalho
16.
Nutr. hosp ; 37(3): 524-533, mayo-jun. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-193860

RESUMO

BACKGROUND: food is a powerful reinforcer that motivates people to eat. The TaqI A1 polymorphism (rs1800497; T>C) downstream of the dopamine D2 receptor (DRD2) gene has been associated with diminished DRD2 receptor density, higher food reinforcement, and impaired eating behavior in adults. OBJECTIVE: to evaluate the association between the rs1800497 polymorphism and the reinforcing value of food and eating in the absence of hunger in Chilean children. MATERIAL AND METHOD: nineteen Chilean children (aged 8-12 years) who were carriers of the A1-allele and 19 age- and gender-matched non-carriers (A2-allele) were evaluated on the reinforcing value of food and eating in the absence of hunger. Anthropometric measures were performed by standard procedures. Briefly, children received a standard pre-load lunch followed by an ad-libitum exposure to palatable foods. RESULTS: no differences were found between A1-allele carriers and non-carriers, whether obese or non-obese, in ad libitum energy intake, macronutrient consumption, or the relative reinforcing value of food (p > 0.05). In obese children, A1 carriers reported significantly lower satiety and fullness before lunch (p < 0.05). However, in children with normal weight A1 carriers were found to exhibit trends for greater satiety and fullness before lunch when compared to non-carriers, but this trend reversed after lunch such that carriers exhibited lower satiety and fullness (p = 0.06). CONCLUSIONS: although TaqI A1 may play an important role in some eating behavior-related traits such as satiety and fullness, especially in obese children, our findings indicate that this polymorphism does not appear to affect eating in the absence of hunger or food reinforcement in children


ANTECEDENTES: los alimentos son un poderoso reforzador de la alimentación. El polimorfismo TaqI A1 (rs1800497; T> C) del gen del receptor 2 de dopamina (DRD2) se ha asociado con una menor densidad de DRD2, un mayor refuerzo alimentario y un comportamiento alimentario alterado en adultos. OBJETIVO: evaluar la asociación entre el polimorfismo rs1800497, el valor reforzador del alimento y la conducta de comer en ausencia de hambre en niños chilenos. MATERIAL Y MÉTODO: treinta y ocho niños chilenos, 19 portadores del alelo A1 y 19 no portadores (alelo A2), pareados por género y edad, fueron evaluados en condiciones de laboratorio para determinar el valor reforzador del alimento y la conducta de comer en ausencia de hambre. Las mediciones antropométricas se realizaron por procedimientos estándar. Brevemente, los niños recibieron un almuerzo estándar seguido de una exposición ad-libitum a alimentos sabrosos. RESULTADOS: no hubo diferencias en la ingesta ad libitum de energía, ni en el consumo de macronutrientes, ni en el valor reforzador del alimento entre los portadores del alelo A1 frente a los no portadores (p > 0,05). Entre los niños obesos, los portadores del alelo A1 reportaron un menor nivel de saciedad y plenitud pre-almuerzo (p < 0,05). Sin embargo, entre los niños con normopeso se observó que los portadores de A1 tenían tendencia a presentar un mayor grado de saciedad y plenitud (pre-almuerzo) frente a los no portadores. Esta tendencia se invirtió post-almuerzo, de modo que los portadores exhibieron menor saciedad y plenitud (p = 0,06). CONCLUSIONES: la variante TaqI A1 podría desempeñar un papel importante en algunos rasgos relacionados con la conducta alimentaria, como la saciedad y la plenitud


Assuntos
Humanos , Masculino , Feminino , Criança , Fome/fisiologia , Variação Genética/genética , Comportamento Alimentar/fisiologia , Ingestão de Energia/genética , Obesidade/genética , Receptores de Dopamina D2/genética , Chile , Variação Genética/efeitos dos fármacos , Polimorfismo Genético/genética , Antropometria , Peso Corporal/genética , Ingestão de Energia/fisiologia , Receptores de Dopamina D2/fisiologia
17.
Nat Commun ; 11(1): 2695, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483258

RESUMO

Obesity and type 2 diabetes (T2D) are metabolic disorders influenced by lifestyle and genetic factors that are characterized by insulin resistance in skeletal muscle, a prominent site of glucose disposal. Numerous genetic variants have been associated with obesity and T2D, of which the majority are located in non-coding DNA regions. This suggests that most variants mediate their effect by altering the activity of gene-regulatory elements, including enhancers. Here, we map skeletal muscle genomic enhancer elements that are dynamically regulated after exposure to the free fatty acid palmitate or the inflammatory cytokine TNFα. By overlapping enhancer positions with the location of disease-associated genetic variants, and resolving long-range chromatin interactions between enhancers and gene promoters, we identify target genes involved in metabolic dysfunction in skeletal muscle. The majority of these genes also associate with altered whole-body metabolic phenotypes in the murine BXD genetic reference population. Thus, our combined genomic investigations identified genes that are involved in skeletal muscle metabolism.


Assuntos
Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Elementos Facilitadores Genéticos , Resistência à Insulina/genética , Músculo Esquelético/metabolismo , Obesidade/genética , Obesidade/metabolismo , Animais , Linhagem Celular , Cromatina/genética , Cromatina/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Masculino , Camundongos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Obesidade/patologia , Ácido Palmítico/farmacologia , Fatores de Iniciação de Peptídeos/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa/farmacologia
18.
PLoS One ; 15(6): e0234465, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544194

RESUMO

Obesity leads a crucial importance in metabolic disorders, as well as type 2 diabetes mellitus. Our present study was designed to assess the potential role of irisin, adiponectin, leptin and gene polymorphism of PNPLA3, leptin and adiponectin as predictive markers of diabetes associated with obesity. One hundred eighty subjects were distributed to three groups including; healthy non-diabetic non obese volunteers as a control group, diabetic non obese group, and diabetic obese group (n = 60 for each group). Fasting blood samples of all groups were collected to determine fasting blood glucose, insulin levels, insulin resistance, total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triacylglycerol, irisin, adiponectin, leptin; as well as, polymorphism of PNPLA3, adiponectin and leptin. The results showed that glucose, insulin resistance, total cholesterol, irisin, leptin, LDL-C, triacylglycerol concentrations were significantly increased, however, insulin, HDL-C, adiponectin were significantly decreased in diabetic obese patients in relation to diabetic non-obese patients as well as in healthy volunteers. The polymorphism of PNPLA3 rs738409 was linearly related to irisin and leptin but was not related with circulating concentrations of adiponectin. We concluded that increased irisin and leptin levels can predict the insulin resistance in obese patients. Moreover, patients who have mutant genotype of PNPLA3 I148 gene (rs738409) C>G, ADIPOQ gene (rs266729) G>C and LEP gene (rs2167270) G>A showed a significant higher susceptibility rate for DM in obese people than those with wild type. This could be considered as an adjustable retort to counter the impact of obesity on glucose homeostasis.


Assuntos
Adiponectina/genética , Diabetes Mellitus Tipo 2/etiologia , Predisposição Genética para Doença , Resistência à Insulina/genética , Leptina/genética , Lipase/genética , Proteínas de Membrana/genética , Obesidade/complicações , Obesidade/genética , Adiponectina/sangue , Adulto , Feminino , Fibronectinas/sangue , Fibronectinas/genética , Marcadores Genéticos , Humanos , Leptina/sangue , Lipase/sangue , Masculino , Proteínas de Membrana/sangue , Polimorfismo Genético , Adulto Jovem
20.
Arch Endocrinol Metab ; 64(3): 205-222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555987

RESUMO

The Human Genome Project has significantly broadened our understanding of the molecular aspects regulating the homeostasis and the pathophysiology of different clinical conditions. Consequently, the field of nutrition has been strongly influenced by such improvements in knowledge - especially for determining how nutrients act at the molecular level in different conditions, such as obesity, type 2 diabetes, cardiovascular disease, and cancer. In this manner, characterizing how the genome influences the diet and vice-versa provides insights about the molecular mechanisms involved in chronic inflammation-related diseases. Therefore, the present review aims to discuss the potential application of Nutritional Genomics to modulate obesity-related inflammatory responses. Arch Endocrinol Metab. 2020;64(3):205-22.


Assuntos
Dieta Mediterrânea , Inflamação/genética , Nutrigenômica , Obesidade/genética , Doença Crônica , Predisposição Genética para Doença , Humanos , Inflamação/metabolismo , Obesidade/metabolismo
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