1
|
Pahl MC, Grant SFA, Leibel RL, Stratigopoulos G. Technologies, strategies, and cautions when deconvoluting genome-wide association signals: FTO in focus. Obes Rev 2023; 24:e13558. [PMID: 36882962 DOI: 10.1111/obr.13558] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 10/08/2022] [Accepted: 01/31/2023] [Indexed: 03/09/2023]
Abstract
Genome-wide association studies have revealed a plethora of genetic variants that correlate with polygenic conditions. However, causal molecular mechanisms have proven challenging to fully define. Without such information, the associations are not physiologically useful or clinically actionable. By reviewing studies of the FTO locus in the genetic etiology of obesity, we wish to highlight advances in the field fueled by the evolution of technical and analytic strategies in assessing the molecular bases for genetic associations. Particular attention is drawn to extrapolating experimental findings from animal models and cell types to humans, as well as technical aspects used to identify long-range DNA interactions and their biological relevance with regard to the associated trait. A unifying model is proposed by which independent obesogenic pathways regulated by multiple FTO variants and genes are integrated at the primary cilium, a cellular antenna where signaling molecules that control energy balance convene.
Collapse
Affiliation(s)
- Matthew C Pahl
- Center for Spatial and Functional Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Struan F A Grant
- Center for Spatial and Functional Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Division of Diabetes and Endocrinology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Department of Pediatrics, The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.,Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rudolph L Leibel
- Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, New York, USA.,Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA
| | - George Stratigopoulos
- Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, New York, USA.,Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA
| |
Collapse
|
2
|
Le N, Sayers S, Mata-Pacheco V, Wagner EJ. The PACAP Paradox: Dynamic and Surprisingly Pleiotropic Actions in the Central Regulation of Energy Homeostasis. Front Endocrinol (Lausanne) 2022; 13:877647. [PMID: 35721722 PMCID: PMC9198406 DOI: 10.3389/fendo.2022.877647] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/30/2022] [Indexed: 12/11/2022] Open
Abstract
Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP), a pleiotropic neuropeptide, is widely distributed throughout the body. The abundance of PACAP expression in the central and peripheral nervous systems, and years of accompanying experimental evidence, indicates that PACAP plays crucial roles in diverse biological processes ranging from autonomic regulation to neuroprotection. In addition, PACAP is also abundantly expressed in the hypothalamic areas like the ventromedial and arcuate nuclei (VMN and ARC, respectively), as well as other brain regions such as the nucleus accumbens (NAc), bed nucleus of stria terminalis (BNST), and ventral tegmental area (VTA) - suggesting that PACAP is capable of regulating energy homeostasis via both the homeostatic and hedonic energy balance circuitries. The evidence gathered over the years has increased our appreciation for its function in controlling energy balance. Therefore, this review aims to further probe how the pleiotropic actions of PACAP in regulating energy homeostasis is influenced by sex and dynamic changes in energy status. We start with a general overview of energy homeostasis, and then introduce the integral components of the homeostatic and hedonic energy balance circuitries. Next, we discuss sex differences inherent to the regulation of energy homeostasis via these two circuitries, as well as the activational effects of sex steroid hormones that bring about these intrinsic disparities between males and females. Finally, we explore the multifaceted role of PACAP in regulating homeostatic and hedonic feeding through its actions in regions like the NAc, BNST, and in particular the ARC, VMN and VTA that occur in sex- and energy status-dependent ways.
Collapse
Affiliation(s)
- Nikki Le
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Sarah Sayers
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Veronica Mata-Pacheco
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Edward J. Wagner
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, United States
| |
Collapse
|
3
|
Identificación del fenotipo ahorrador para la personalización del manejo del sobrepeso y la obesidad. REVISTA MÉDICA CLÍNICA LAS CONDES 2022. [DOI: 10.1016/j.rmclc.2022.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
4
|
Stammers L, Wong L, Brown R, Price S, Ekinci E, Sumithran P. Identifying stress-related eating in behavioural research: A review. Horm Behav 2020; 124:104752. [PMID: 32305343 DOI: 10.1016/j.yhbeh.2020.104752] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 03/26/2020] [Accepted: 04/07/2020] [Indexed: 11/29/2022]
Abstract
Stress is a commonly reported precipitant of overeating. Understanding the relationship between stress and food intake is important, particularly in view of the increasing prevalence of obesity. The purpose of this review is to examine how stress-related eating has been defined and measured in the literature to date. There are no established diagnostic criteria or gold standards for quantification of stress-related eating. Questionnaires relying on the accuracy of self-report are the mainstay of identifying people who tend to eat in response to stress and emotions. There is a paucity of clinical research linking objective measurements of stress and appetite with self-reported eating behaviour. Limitations of the methodological approaches used and the heterogeneity between studies leave significant knowledge gaps in our understanding of the mechanism of stress related eating, and how best to identify it. These issues are discussed, and areas for further research are explored.
Collapse
Affiliation(s)
- Lauren Stammers
- Department of Medicine (Austin), University of Melbourne, 145 Studley Road, Heidelberg, Victoria, Australia; Department of Endocrinology, Austin Health, 300 Waterdale Road, Heidelberg Heights, Victoria, Australia.
| | - Lisa Wong
- Department of Medicine (Austin), University of Melbourne, 145 Studley Road, Heidelberg, Victoria, Australia; Department of Endocrinology, Austin Health, 300 Waterdale Road, Heidelberg Heights, Victoria, Australia.
| | - Robyn Brown
- Florey Institute of Neuroscience and Mental Health, 30 Royal Parade, University of Melbourne, Parkville, Victoria, Australia.
| | - Sarah Price
- Department of Medicine (Austin), University of Melbourne, 145 Studley Road, Heidelberg, Victoria, Australia.
| | - Elif Ekinci
- Department of Medicine (Austin), University of Melbourne, 145 Studley Road, Heidelberg, Victoria, Australia; Department of Endocrinology, Austin Health, 300 Waterdale Road, Heidelberg Heights, Victoria, Australia.
| | - Priya Sumithran
- Department of Medicine (Austin), University of Melbourne, 145 Studley Road, Heidelberg, Victoria, Australia; Department of Endocrinology, Austin Health, 300 Waterdale Road, Heidelberg Heights, Victoria, Australia.
| |
Collapse
|
5
|
Dorling JL, Clayton DJ, Jones J, Carter WG, Thackray AE, King JA, Pucci A, Batterham RL, Stensel DJ. A randomized crossover trial assessing the effects of acute exercise on appetite, circulating ghrelin concentrations, and butyrylcholinesterase activity in normal-weight males with variants of the obesity-linked FTO rs9939609 polymorphism. Am J Clin Nutr 2019; 110:1055-1066. [PMID: 31504106 DOI: 10.1093/ajcn/nqz188] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 07/18/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The fat mass and obesity-associated gene (FTO) rs9939609 A-allele is associated with higher acyl-ghrelin (AG) concentrations, higher energy intake, and obesity, although exercise may mitigate rs9939609 A-allele-linked obesity risk. Butyrylcholinesterase (BChE) hydrolyzes AG to des-acyl-ghrelin (DAG), potentially decreasing appetite. However, the effects of the FTO rs9939609 genotype and exercise on BChE activity, AG, DAG, and energy intake are unknown. OBJECTIVE We hypothesized that individuals homozygous for the obesity-risk A-allele (AAs) would exhibit higher postprandial AG and energy intake than individuals homozygous for the low obesity-risk T-allele (TTs), but that exercise would increase BChE activity and diminish these differences. METHODS Twelve AA and 12 TT normal-weight males completed a control (8 h rest) and an exercise (1 h of exercise at 70% peak oxygen uptake, 7 h rest) trial in a randomized crossover design. A fixed meal was consumed at 1.5 h and an ad libitum buffet meal at 6.5 h. Appetite, appetite-related hormones, BChE activity, and energy intake were assessed. RESULTS AAs displayed lower baseline BChE activity, higher baseline AG:DAG ratio, attenuated AG suppression after a fixed meal, and higher ad libitum energy intake compared with TTs [effect sizes (ESs) ≥ 0.72, P ≤ 0.049]. Exercise increased Δ BChE activity in both genotypes (ESs = 0.37, P = 0.004); however, exercise lowered AG and the AG:DAG ratio to a greater extent in AAs (P ≤ 0.023), offsetting the higher AG profile observed in AAs during the control trial (ESs ≥ 1.25, P ≤ 0.048). Exercise did not elevate energy intake in either genotype (P = 0.282). CONCLUSIONS Exercise increases BChE activity, suppresses AG and the AG:DAG ratio, and corrects the higher AG profile observed in obesity-risk AA individuals. These findings suggest that exercise or other methods targeting BChE activity may offer a preventative and/or therapeutic strategy for AA individuals. This trial was registered at clinicaltrials.gov as NCT03025347.
Collapse
Affiliation(s)
- James L Dorling
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise, and Health Sciences, Loughborough University, Loughborough, United Kingdom.,Ingestive Behavior Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - David J Clayton
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise, and Health Sciences, Loughborough University, Loughborough, United Kingdom.,School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Jenny Jones
- Centre for Obesity Research, University College London, London, United Kingdom
| | - Wayne G Carter
- School of Medicine, University of Nottingham Medical School, Royal Derby Hospital Centre, Derby, United Kingdom
| | - Alice E Thackray
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise, and Health Sciences, Loughborough University, Loughborough, United Kingdom.,University Hospitals of Leicester National Health Service Trust, Leicester, United Kingdom
| | - James A King
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise, and Health Sciences, Loughborough University, Loughborough, United Kingdom.,University Hospitals of Leicester National Health Service Trust, Leicester, United Kingdom
| | - Andrea Pucci
- Centre for Obesity Research, University College London, London, United Kingdom.,University College London Hospitals Bariatric Centre for Weight Management and Metabolic Surgery, London, United Kingdom
| | - Rachel L Batterham
- Centre for Obesity Research, University College London, London, United Kingdom.,University College London Hospitals Bariatric Centre for Weight Management and Metabolic Surgery, London, United Kingdom.,National Institute of Health Research, University College London Hospitals Biomedical Research Centre, London, United Kingdom
| | - David J Stensel
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise, and Health Sciences, Loughborough University, Loughborough, United Kingdom.,University Hospitals of Leicester National Health Service Trust, Leicester, United Kingdom
| |
Collapse
|
6
|
Wang L, De Solis AJ, Goffer Y, Birkenbach KE, Engle SE, Tanis R, Levenson JM, Li X, Rausch R, Purohit M, Lee JY, Tan J, De Rosa MC, Doege CA, Aaron HL, Martins GJ, Brüning JC, Egli D, Costa R, Berbari N, Leibel RL, Stratigopoulos G. Ciliary gene RPGRIP1L is required for hypothalamic arcuate neuron development. JCI Insight 2019; 4:e123337. [PMID: 30728336 PMCID: PMC6413800 DOI: 10.1172/jci.insight.123337] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 01/03/2019] [Indexed: 12/16/2022] Open
Abstract
Intronic polymorphisms in the α-ketoglutarate-dependent dioxygenase gene (FTO) that are highly associated with increased body weight have been implicated in the transcriptional control of a nearby ciliary gene, retinitis pigmentosa GTPase regulator-interacting protein-1 like (RPGRIP1L). Previous studies have shown that congenital Rpgrip1l hypomorphism in murine proopiomelanocortin (Pomc) neurons causes obesity by increasing food intake. Here, we show by congenital and adult-onset Rpgrip1l deletion in Pomc-expressing neurons that the hyperphagia and obesity are likely due to neurodevelopmental effects that are characterized by a reduction in the Pomc/Neuropeptide Y (Npy) neuronal number ratio and marked increases in arcuate hypothalamic-paraventricular hypothalamic (ARH-PVH) axonal projections. Biallelic RPGRIP1L mutations result in fewer cilia-positive human induced pluripotent stem cell-derived (iPSC-derived) neurons and blunted responses to Sonic Hedgehog (SHH). Isogenic human ARH-like embryonic stem cell-derived (ESc-derived) neurons homozygous for the obesity-risk alleles at rs8050136 or rs1421085 have decreased RPGRIP1L expression and have lower numbers of POMC neurons. RPGRIP1L overexpression increases POMC cell number. These findings suggest that apparently functional intronic polymorphisms affect hypothalamic RPGRIP1L expression and impact development of POMC neurons and their derivatives, leading to hyperphagia and increased adiposity.
Collapse
Affiliation(s)
- Liheng Wang
- Naomi Berrie Diabetes Center and Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Alain J. De Solis
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Yossef Goffer
- Naomi Berrie Diabetes Center & Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, New York, USA
| | - Kathryn E. Birkenbach
- Naomi Berrie Diabetes Center & Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, New York, USA
| | - Staci E. Engle
- Department of Biology, Indiana University-Purdue University, Indianapolis, Indiana, USA
| | - Ross Tanis
- University of South Carolina School of Medicine, Columbia, South Carolina, USA
| | - Jacob M. Levenson
- University of Central Florida College of Medicine, Orlando, Florida, USA
| | - Xueting Li
- Institute of Human Nutrition graduate program, Columbia University, New York, New York, USA
| | - Richard Rausch
- Naomi Berrie Diabetes Center & Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, New York, USA
| | - Manika Purohit
- Zuckerman Institute, Columbia University, New York, New York, USA
| | - Jen-Yi Lee
- Cancer Research Laboratory Molecular Imaging Center, University of California, Berkeley, 94720, USA
| | - Jerica Tan
- Naomi Berrie Diabetes Center, Columbia Stem Cell Initiative, Department of Pathology and Cell Biology, Columbia University, New York, New York, USA
| | - Maria Caterina De Rosa
- Naomi Berrie Diabetes Center, Columbia Stem Cell Initiative, Department of Pathology and Cell Biology, Columbia University, New York, New York, USA
| | - Claudia A. Doege
- Naomi Berrie Diabetes Center, Columbia Stem Cell Initiative, Department of Pathology and Cell Biology, Columbia University, New York, New York, USA
| | - Holly L. Aaron
- Cancer Research Laboratory Molecular Imaging Center, University of California, Berkeley, 94720, USA
| | | | - Jens C. Brüning
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Cologne, Germany
- Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- National Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Dieter Egli
- Naomi Berrie Diabetes Center & Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, New York, USA
| | - Rui Costa
- Zuckerman Institute, Columbia University, New York, New York, USA
| | - Nicolas Berbari
- Department of Biology, Indiana University-Purdue University, Indianapolis, Indiana, USA
| | - Rudolph L. Leibel
- Naomi Berrie Diabetes Center & Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, New York, USA
| | - George Stratigopoulos
- Naomi Berrie Diabetes Center & Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, New York, USA
| |
Collapse
|
7
|
Kroll C, de França PHC, Mastroeni MF. Association betweenFTOgene polymorphism and excess body weight in women from before to after pregnancy: A cohort study. Am J Hum Biol 2018; 30:e23164. [DOI: 10.1002/ajhb.23164] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 06/05/2018] [Accepted: 06/10/2018] [Indexed: 01/31/2023] Open
Affiliation(s)
- Caroline Kroll
- Post-graduate Program in Health and Environment; University of Joinville Region - UNIVILLE; Joinville Santa Catarina Brazil
| | | | - Marco Fabio Mastroeni
- Post-graduate Program in Health and Environment; University of Joinville Region - UNIVILLE; Joinville Santa Catarina Brazil
| |
Collapse
|
8
|
Obregón Rivas AM, Santos JL, Valladares MA, Cameron J, Goldfield G. Association of the FTO fat mass and obesity-associated gene rs9939609 polymorphism with rewarding value of food and eating behavior in Chilean children. Nutrition 2018; 54:105-110. [PMID: 29778907 DOI: 10.1016/j.nut.2018.03.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 03/08/2018] [Accepted: 03/10/2018] [Indexed: 01/19/2023]
Abstract
OBJECTIVES The aim of this study was to assess the association between the single-nucleotide polymorphism rs9939609 in the FTO gene and homeostatic/non-homeostatic eating behavior patterns in Chilean children. METHODS A cross-sectional study was conducted in 258 children (44% female; 8-14 y of age). Anthropometric measurements (weight, height, Z-score of height, body mass index, and waist circumference) were performed. Eating behavior was assessed using the Eating in Absence of Hunger Questionnaire; the Child Eating Behavior Questionnaire; the Three Factor Eating Questionnaire, and the Food Reinforcement Value Questionnaire. Genotype of rs9939609 was determined by a Taqman assay. Association of rs9939609 with eating behavior was assessed using non-parametric tests. RESULTS Allelic frequencies of rs9939609 were estimated as 77% for the A allele and 23% for the T allele. We found that normal-weight girl A carriers had higher scores of Satiety Responsiveness and Slowness on the Eating subscale. Normal-weight boy A carriers showed significantly higher scores on the Negative Affect and lower scores of the Desire to Drink subscale. In overweight children, A carriers showed higher scores on the Food Responsiveness, Emotional Overeating, Enjoyment of Food, and Food Choice subscales and lower scores on the Satiety- Responsiveness and Slowness in Eating subscales. In obese children, we found higher scores on the Cognitive Restrained subscale and lower Food Choice. CONCLUSION The rs9939609 A allele of the FTO gene is associated with eating behavior traits and may predispose to obesity.
Collapse
Affiliation(s)
- Ana Maria Obregón Rivas
- Escuela de Nutrición y dietética, Facultad de Ciencias para el cuidado de la Salud, Universidad San Sebastián, Concepción, Chile.
| | - Jose L Santos
- Departamento de Nutrición, Diabetes y Metabolismo, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Macarena A Valladares
- Departamento de Ciencias Químicas y Biológicas, Universidad Bernardo O Higgins, Santiago, Chile
| | - Jameson Cameron
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - Gary Goldfield
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| |
Collapse
|
9
|
Zhou Y, Hambly BD, McLachlan CS. FTO associations with obesity and telomere length. J Biomed Sci 2017; 24:65. [PMID: 28859657 PMCID: PMC5580219 DOI: 10.1186/s12929-017-0372-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 08/23/2017] [Indexed: 12/16/2022] Open
Abstract
This review examines the biology of the Fat mass- and obesity-associated gene (FTO), and the implications of genetic association of FTO SNPs with obesity and genetic aging. Notably, we focus on the role of FTO in the regulation of methylation status as possible regulators of weight gain and genetic aging. We present a theoretical review of the FTO gene with a particular emphasis on associations with UCP2, AMPK, RBL2, IRX3, CUX1, mTORC1 and hormones involved in hunger regulation. These associations are important for dietary behavior regulation and cellular nutrient sensing via amino acids. We suggest that these pathways may also influence telomere regulation. Telomere length (TL) attrition may be influenced by obesity-related inflammation and oxidative stress, and FTO gene-involved pathways. There is additional emerging evidence to suggest that telomere length and obesity are bi-directionally associated. However, the role of obesity risk-related genotypes and associations with TL are not well understood. The FTO gene may influence pathways implicated in regulation of TL, which could help to explain some of the non-consistent relationship between weight phenotype and telomere length that is observed in population studies investigating obesity.
Collapse
Affiliation(s)
- Yuling Zhou
- Rural Clinical School, University of New South Wales, Sydney, 2052, Australia
| | - Brett D Hambly
- Discipline of Pathology and Bosch Institute, University of Sydney, Sydney, Australia
| | - Craig S McLachlan
- Rural Clinical School, University of New South Wales, Sydney, 2052, Australia.
| |
Collapse
|
10
|
Abstract
A cluster of single nucleotide polymorphisms (SNPs) in the first intron of the fat mass and obesity related (FTO) gene were the first common variants discovered to be associated with body mass index and body fatness. This review summarises what has been later discovered about the biology of FTO drawing together information from both human and animal studies. Subsequent work showed that the 'at risk' alleles of these SNPs are associated with greater food intake and increased hunger/lowered satiety, but are not associated with altered resting energy expenditure or low physical activity in humans. FTO is an FE (II) and 2-oxoglutarate dependent DNA/RNA methylase. Contrasting the impact of the SNPs on energy balance in humans, knocking out or reducing activity of the Fto gene in the mouse resulted in lowered adiposity, elevated energy expenditure with no impact on food intake (but the impact on expenditure is disputed). In contrast, overexpression of the gene in mice led to elevated food intake and adiposity, with no impact on expenditure. In rodents, the Fto gene is widely expressed in the brain including hypothalamic nuclei linked to food intake regulation. Since its activity is 2-oxoglutarate dependent it could potentially act as a sensor of citrate acid cycle flux, but this function has been dismissed, and instead it has been suggested to be much more likely to act as an amino acid sensor, linking circulating AAs to the mammalian target of rapamycin complex 1. This may be fundamental to its role in development but the link to obesity is less clear. It has been recently suggested that although the obesity related SNPs reside in the first intron of FTO, they may not only impact FTO but mediate their obesity effects via nearby genes (notably RPGRIP1L and IRX3).
Collapse
Affiliation(s)
- John R Speakman
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 1 Beichen xilu, Chaoyang, Beijing, China.
- Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Ave, Aberdeen, Scotland, AB24 2TZ, UK.
| |
Collapse
|
11
|
Stratigopoulos G, Martin Carli JF, O'Day DR, Wang L, Leduc CA, Lanzano P, Chung WK, Rosenbaum M, Egli D, Doherty DA, Leibel RL. Hypomorphism for RPGRIP1L, a ciliary gene vicinal to the FTO locus, causes increased adiposity in mice. Cell Metab 2014; 19:767-79. [PMID: 24807221 PMCID: PMC4131684 DOI: 10.1016/j.cmet.2014.04.009] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 11/11/2013] [Accepted: 04/18/2014] [Indexed: 12/31/2022]
Abstract
Common polymorphisms in the first intron of FTO are associated with increased body weight in adults. Previous studies have suggested that a CUX1-regulatory element within the implicated FTO region controls expression of FTO and the nearby ciliary gene, RPGRIP1L. Given the role of ciliary genes in energy homeostasis, we hypothesized that mice hypomorphic for Rpgrip1l would display increased adiposity. We find that Rpgrip1l⁺/⁻ mice are hyperphagic and fatter, and display diminished suppression of food intake in response to leptin administration. In the hypothalamus of Rpgrip1l⁺/⁻ mice, and in human fibroblasts with hypomorphic mutations in RPGRIP1L, the number of AcIII-positive cilia is diminished, accompanied by impaired convening of the leptin receptor to the vicinity of the cilium, and diminished pStat3 in response to leptin. These findings suggest that RPGRIP1L may be partly or exclusively responsible for the obesity susceptibility signal at the FTO locus.
Collapse
Affiliation(s)
- George Stratigopoulos
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
| | - Jayne F Martin Carli
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Diana R O'Day
- Divisions of Developmental Medicine and Genetic Medicine, Department of Pediatrics, Seattle Children's Research Institute and University of Washington 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Liheng Wang
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Charles A Leduc
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Patricia Lanzano
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Wendy K Chung
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Michael Rosenbaum
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Dieter Egli
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Daniel A Doherty
- Divisions of Developmental Medicine and Genetic Medicine, Department of Pediatrics, Seattle Children's Research Institute and University of Washington 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Rudolph L Leibel
- Naomi Berrie Diabetes Center and Division of Molecular Genetics, Department of Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
| |
Collapse
|
12
|
Portella AK, Silveira PP. Neurobehavioral determinants of nutritional security in fetal growth-restricted individuals. Ann N Y Acad Sci 2014; 1331:15-33. [DOI: 10.1111/nyas.12390] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- André Krumel Portella
- Hospital da Criança Santo Antônio; Santa Casa de Misericórdia de Porto Alegre; Rio Grande do Sul; Brazil
| | - Patrícia Pelufo Silveira
- Departamento de Pediatria, Faculdade de Medicina; Universidade Federal do Rio Grande do Sul; Rio Grande do Sul; Brazil
| |
Collapse
|
13
|
Park SL, Cheng I, Pendergrass SA, Kucharska-Newton AM, Lim U, Ambite JL, Caberto CP, Monroe KR, Schumacher F, Hindorff LA, Oetjens MT, Wilson S, Goodloe RJ, Love SA, Henderson BE, Kolonel LN, Haiman CA, Crawford DC, North KE, Heiss G, Ritchie MD, Wilkens LR, Le Marchand L. Association of the FTO obesity risk variant rs8050136 with percentage of energy intake from fat in multiple racial/ethnic populations: the PAGE study. Am J Epidemiol 2013; 178:780-90. [PMID: 23820787 DOI: 10.1093/aje/kwt028] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Common obesity risk variants have been associated with macronutrient intake; however, these associations' generalizability across populations has not been demonstrated. We investigated the associations between 6 obesity risk variants in (or near) the NEGR1, TMEM18, BDNF, FTO, MC4R, and KCTD15 genes and macronutrient intake (carbohydrate, protein, ethanol, and fat) in 3 Population Architecture using Genomics and Epidemiology (PAGE) studies: the Multiethnic Cohort Study (1993-2006) (n = 19,529), the Atherosclerosis Risk in Communities Study (1987-1989) (n = 11,114), and the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) Study, which accesses data from the Third National Health and Nutrition Examination Survey (1991-1994) (n = 6,347). We used linear regression, with adjustment for age, sex, and ethnicity, to estimate the associations between obesity risk genotypes and macronutrient intake. A fixed-effects meta-analysis model showed that the FTO rs8050136 A allele (n = 36,973) was positively associated with percentage of calories derived from fat (βmeta = 0.2244 (standard error, 0.0548); P = 4 × 10(-5)) and inversely associated with percentage of calories derived from carbohydrate (βmeta = -0.2796 (standard error, 0.0709); P = 8 × 10(-5)). In the Multiethnic Cohort Study, percentage of calories from fat assessed at baseline was a partial mediator of the rs8050136 effect on body mass index (weight (kg)/height (m)(2)) obtained at 10 years of follow-up (mediation of effect = 0.0823 kg/m(2), 95% confidence interval: 0.0559, 0.1128). Our data provide additional evidence that the association of FTO with obesity is partially mediated by dietary intake.
Collapse
Affiliation(s)
- Sungshim Lani Park
- Epidemiology Program, University of Hawaii Cancer Center, 701 Ilalo Street, Honolulu, HI 96813, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Reina SA, Shomaker LB, Mooreville M, Courville AB, Brady SM, Olsen C, Yanovski SZ, Tanofsky-Kraff M, Yanovski JA. Sociocultural pressures and adolescent eating in the absence of hunger. Body Image 2013; 10:182-90. [PMID: 23394966 PMCID: PMC3671847 DOI: 10.1016/j.bodyim.2012.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 12/24/2012] [Accepted: 12/27/2012] [Indexed: 01/31/2023]
Abstract
Parental feeding practices and sociocultural pressures theoretically influence eating behavior. Yet, whether these factors relate to eating in the absence of hunger (EAH) is unknown. We assessed if sociocultural pressures were associated with EAH among 90 adolescents (Mage=15.27, SD=1.39; 48% female). Parents completed the Child Feeding Questionnaire. Adolescents completed the Perceived Sociocultural Pressures Scale, Sociocultural Attitudes Towards Appearance Questionnaire-3, and Multidimensional Body Self-Relations Questionnaire-Appearance Scales. On two occasions, EAH was assessed as snack food intake after adolescents ate to satiety. Controlling for body composition and demographics, parental restriction and family pressure to be thin were associated with greater EAH. Media pressure was related to more EAH in girls. Appearance orientation and preoccupation with becoming overweight mediated links between sociocultural pressures and EAH. Findings support the notion that sociocultural pressures and their links to body image may contribute to the course of disinhibited eating behaviors during adolescence.
Collapse
Affiliation(s)
- Samantha A. Reina
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Lauren B. Shomaker
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
- Department of Medical and Clinical Psychology (MPS), Uniformed Services University of the Health Sciences (USUHS), Bethesda, MD, United States
| | - Mira Mooreville
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | | | - Sheila M. Brady
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Cara Olsen
- Department of Preventive Medicine and Biometrics, USUHS, Bethesda, MD, United States
| | - Susan Z. Yanovski
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
- Division of Digestive Diseases and Nutrition, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, MD, United States
| | - Marian Tanofsky-Kraff
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
- Department of Medical and Clinical Psychology (MPS), Uniformed Services University of the Health Sciences (USUHS), Bethesda, MD, United States
| | - Jack A. Yanovski
- Section on Growth and Obesity, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver, National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD, United States
| |
Collapse
|
15
|
Wehby GL, von Hinke Kessler Scholder S. Genetic instrumental variable studies of effects of prenatal risk factors. BIODEMOGRAPHY AND SOCIAL BIOLOGY 2013; 59:4-36. [PMID: 23701534 PMCID: PMC3690512 DOI: 10.1080/19485565.2013.774615] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Identifying the effects of maternal risk factors during pregnancy on infant and child health is an area of tremendous research interest. However, policymakers are primarily interested in unraveling the causal effects of prenatal risk factors, not their associations with child health, which may be confounded by several unobserved factors. In this article, we evaluate the utility of genetic variants in three genes that have unequivocal evidence of being related to three major risk factors-CHRNA3 for smoking, ADH1B for alcohol use, and FTO for obesity-as instrumental variables for identifying the causal effects of such factors during pregnancy. Using two independent datasets, we find that these variants are overall predictive of the risk factors and are not systematically related to observed confounders, suggesting that they may be useful instruments. We also find some suggestive evidence that genetic effects are stronger during than before pregnancy. We provide an empirical example illustrating the use of these genetic variants as instruments to evaluate the effects of risk factors on birth weight. Finally, we offer suggestions for researchers contemplating the use of these variants as instruments.
Collapse
Affiliation(s)
- George L. Wehby
- Assistant Professor, Department of Health Management and Policy, College of Public Health, University of Iowa, 200 Hawkins Drive, E205 GH, Iowa City, IA 52242, Phone: 1-319-384-5133, Fax: 1-319-384-5125,
| | | |
Collapse
|
16
|
Kral TVE, Allison DB, Birch LL, Stallings VA, Moore RH, Faith MS. Caloric compensation and eating in the absence of hunger in 5- to 12-y-old weight-discordant siblings. Am J Clin Nutr 2012; 96:574-83. [PMID: 22854400 PMCID: PMC3417216 DOI: 10.3945/ajcn.112.037952] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND An impaired ability to compensate for calories and increased eating in the absence of hunger (EAH) has been associated with increased energy intake and weight gain in unrelated children. OBJECTIVE The aims of this study were to compare caloric compensation [the percentage compensation index (%COMPX)] and EAH in weight-discordant siblings aged 5-12 y. DESIGN In a crossover, behavioral genetics design, 47 same-sex sibling pairs (53% female, 55% full siblings) were served dinner once a week for 3 wk. Across conditions, siblings were served the same dinner, but 25 min before dinner, they either consumed in full or did not consume 1 of 2 preloads that varied in energy density (ED; 0.57 or 0.97 kcal/g). On the day when no preload was consumed, EAH was assessed after dinner and defined as the number of calories consumed from snacks. RESULTS Overweight/obese siblings undercompensated [%COMPX: -48.8 ± 56.3 (mean ± SEM)] and therefore overate after the high-ED preload, whereas normal-weight siblings showed accurate compensation (%COMPX: 101.3 ± 51.9; P = 0.03). Furthermore, overweight/obese siblings consumed 34% more calories (93 kcal) in the absence of hunger than did normal-weight siblings (P = 0.01). Within-pair resemblances for %COMPX and EAH were stronger for full siblings (P < 0.049) than for half siblings (P > 0.23). CONCLUSIONS An impaired ability to regulate short-term energy intake, which includes incomplete adjustment for calorie differences in a preload and eating when satiated, may represent a behavioral phenotype for obesity in children. Future studies should test whether teaching children to focus on internal satiety cues may prevent at-risk children from overeating.
Collapse
Affiliation(s)
- Tanja V E Kral
- Department of Biobehavioral Health Sciences, University of Pennsylvania School of Nursing and Perelman School of Medicine, Philadelphia, PA 19104, USA.
| | | | | | | | | | | |
Collapse
|
17
|
Yeo GS, O'Rahilly S. Uncovering the biology of FTO. Mol Metab 2012; 1:32-6. [PMID: 24024116 PMCID: PMC3757649 DOI: 10.1016/j.molmet.2012.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 06/21/2012] [Accepted: 06/21/2012] [Indexed: 11/22/2022] Open
Abstract
Genome-wide association studies have revealed that SNPs in the first intron of FTO (Fat mass and Obesity related) are robustly associated with body mass index and obesity. Subsequently, it has become clear that this association with body weight, and increasingly food intake, is replicable across multiple populations and different age groups. However, to date, no conclusive link has been made between the risk alleles and FTO expression or its physiological role. FTO deficiency leads to a complex phenotype including postnatal mortality and growth retardation, pointing to some fundamental developmental role. Yet, the weight of evidence from a number of animal models where FTO expression has been perturbed indicates some role for FTO in energy homoeostasis. In addition, emerging data points to a role for FTO in the sensing of nutrients. In this review, we explore the in vivo and in vitro evidence detailing FTO's different faces and discuss how these might link to the regulation of body weight.
Collapse
Affiliation(s)
- Giles S.H. Yeo
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Stephen O'Rahilly
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| |
Collapse
|
18
|
Pitman RT, Fong JT, Billman P, Puri N. Knockdown of the fat mass and obesity gene disrupts cellular energy balance in a cell-type specific manner. PLoS One 2012; 7:e38444. [PMID: 22675562 PMCID: PMC3367022 DOI: 10.1371/journal.pone.0038444] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Accepted: 05/08/2012] [Indexed: 11/19/2022] Open
Abstract
Recent studies suggest that FTO variants strongly correlate with obesity and mainly influence energy intake with little effect on the basal metabolic rate. We suggest that FTO influences eating behavior by modulating intracellular energy levels and downstream signaling mechanisms which control energy intake and metabolism. Since FTO plays a particularly important role in adipocytes and in hypothalamic neurons, SH-SY5Y neuronal cells and 3T3-L1 adipocytes were used to understand how siRNA mediated knockdown of FTO expression alters cellular energy homeostasis. Cellular energy status was evaluated by measuring ATP levels using a luminescence assay and uptake of fluorescent glucose. FTO siRNA in SH-SY5Y cells mediated mRNA knockdown (−82%), increased ATP concentrations by up to 46% (P = 0.013) compared to controls, and decreased phosphorylation of AMPk and Akt in SH-SY5Y by −52% and −46% respectively as seen by immunoblotting. In contrast, FTO siRNA in 3T3-L1 cells decreased ATP concentration by −93% (p<0.0005), and increased AMPk and Akt phosphorylation by 204% and 70%, respectively suggesting that FTO mediates control of energy levels in a cell-type specific manner. Furthermore, glucose uptake was decreased in both SH-SY5Y (−51% p = 0.015) and 3T3-L1 cells (−30%, p = 0.0002). We also show that FTO knockdown decreases NPY mRNA expression in SH-SY5Y cells (−21%) through upregulation of pSTAT3 (118%). These results provide important evidence that FTO-variant linked obesity may be associated with altered metabolic functions through activation of downstream metabolic mediators including AMPk.
Collapse
Affiliation(s)
- Ryan T. Pitman
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, Illinois, United States of America
| | - Jason T. Fong
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, Illinois, United States of America
| | - Penny Billman
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, Illinois, United States of America
| | - Neelu Puri
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, Illinois, United States of America
- * E-mail:
| |
Collapse
|
19
|
Abstract
Genome-wide association studies have been very powerful, uncovering potentially new biology that would not have been possible using a candidate gene approach. A prime example of this is the gene FTO (fat mass and obesity associated), which first came to light in 2007, when single nucleotide polymorphisms in its first intron were robustly associated with body mass index and obesity. Subsequently, as it became clear that this association with body weight, and increasingly food intake, was replicable across multiple populations and different age groups, attention was turned to studying the biology of FTO, about which absolutely nothing was known. This review focuses on the genetic and biochemical approaches as well as animal models that have been used by us and others since 2007 to try and uncover the complex biology of FTO.
Collapse
Affiliation(s)
- Yi-Chun Loraine Tung
- University of Cambridge Metabolic Research Labs, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, United Kingdom
| | | |
Collapse
|
20
|
Golay A, Anderson R, Visser A. Changing obesity: theories, facts and interventions. PATIENT EDUCATION AND COUNSELING 2010; 79:275-276. [PMID: 20462729 DOI: 10.1016/j.pec.2010.04.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
|