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Parekh P, Begley P, Jessop M, Aplin M, Missir E, McMeekin H, Raczek G, Singh N, Dizdarevic S. Association between body mass index (BMI) and [ 123I]Ioflupane (DaTSCAN) availabilities in patients with parkinsonism using single-photon emission computed tomography-computed tomography (SPECT-CT). Eur J Hybrid Imaging 2023; 7:21. [PMID: 37981626 PMCID: PMC10657921 DOI: 10.1186/s41824-023-00181-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/14/2023] [Indexed: 11/21/2023] Open
Abstract
AIM [123I]Ioflupane (DaTSCAN) has a high binding affinity to the dopamine (DA) transporter (DaT) and tenfold less affinity to serotonin (5-HT) transporter (SERT). Both neurotransmitters are considered to contribute to body weight regulation. This study assesses the association between body mass index (BMI) and DaTSCAN availability in brain. METHOD Scans from 74 consecutive patients who had undergone DaTSCAN single-photon emission computed tomography-computed tomography (SPECT-CT) were used to obtain semi- and absolute quantitative data in several volumes of interest (VOIs). Relative semi-quantitative specific binding ratios (SBRs) from Chang attenuated SPECT were obtained from GE DaTQUANT. Absolute normalised concentration (NC) was calculated from attenuation/scatter corrected SPECT-CT images, using an adapted version of the EARL Ltd (European Association of Nuclear Medicine (EANM) Research 4 Life) template. Scans were subdivided into either degenerative parkinsonism (abnormal = 49), borderline (n = 14) or scan without evidence of dopaminergic deficit (SWEDD = 11) using visual assessment and SBR values by two nuclear medicine consultants. RESULTS SBRs did not correlate with BMI. However, NC values correlated negatively in the entire cohort, with the strongest correlation in the frontal (r = - 0.649. p = 0.000), occipital (r = - 0.555, p = 0.000) regions and pons (r = - 0.555, p = 0.000). In the abnormal (n = 49) and SWEDD group (n = 11), NC of the frontal region was the most correlated with BMI (r = - 0.570, p = 0.000; r = - 0.813, p = 0.002, respectively). In the borderline group (n = 14), the left posterior putamen displayed the strongest correlation (r = - 0.765, p = 0.001). CONCLUSION Absolute NC values demonstrate a strong inverse correlation with BMI, strongest in the extrastriatal regions. Due to the predominately non-overlapping distribution of DaT and SERT, this study suggests greater involvement of SERT in obesity with possible interplay with DA transmission.
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Affiliation(s)
- Puja Parekh
- Brighton and Sussex Medical School, Brighton, England
| | - Patrick Begley
- Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England
| | - Maryam Jessop
- Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England
| | - Mark Aplin
- Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England
| | - Elena Missir
- Brighton and Sussex Medical School, Brighton, England
| | | | - Gosia Raczek
- Brighton and Sussex Medical School, Brighton, England
| | - Nitasha Singh
- Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England
| | - Sabina Dizdarevic
- Clinical Imaging Science Centre, Neuroscience and Medicine, Brighton and Sussex Medical School, Brighton, England.
- Brighton and Sussex Medical School, Brighton, England.
- Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England.
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Obesity and dietary fat influence dopamine neurotransmission: exploring the convergence of metabolic state, physiological stress, and inflammation on dopaminergic control of food intake. Nutr Res Rev 2021; 35:236-251. [PMID: 34184629 DOI: 10.1017/s0954422421000196] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The aim of this review is to explore how metabolic changes induced by diets high in saturated fat (HFD) affect nucleus accumbens (NAc) dopamine neurotransmission and food intake, and to explore how stress and inflammation influence this process. Recent evidence linked diet-induced obesity and HFD with reduced dopamine release and reuptake. Altered dopamine neurotransmission could disrupt satiety circuits between NAc dopamine terminals and projections to the hypothalamus. The NAc directs learning and motivated behaviours based on homeostatic needs and psychological states. Therefore, impaired dopaminergic responses to palatable food could contribute to weight gain by disrupting responses to food cues or stress, which impacts type and quantity of food consumed. Specifically, saturated fat promotes neuronal resistance to anorectic hormones and activation of immune cells that release proinflammatory cytokines. Insulin has been shown to regulate dopamine neurotransmission by enhancing satiety, but less is known about effects of diet-induced stress. Therefore, changes to dopamine signalling due to HFD warrant further examination to characterise crosstalk of cytokines with endocrine and neurotransmitter signals. A HFD promotes a proinflammatory environment that may disrupt neuronal endocrine function and dopamine signalling that could be exacerbated by the hypothalamic-pituitary-adrenal and κ-opioid receptor stress systems. Together, these adaptive changes may dysregulate eating by changing NAc dopamine during hedonic versus homeostatic food intake. This could drive palatable food cravings during energy restriction and hinder weight loss. Understanding links between HFD and dopamine neurotransmission will inform treatment strategies for diet-induced obesity and identify molecular candidates for targeted therapeutics.
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Say YH. The association of insertions/deletions (INDELs) and variable number tandem repeats (VNTRs) with obesity and its related traits and complications. J Physiol Anthropol 2017; 36:25. [PMID: 28615046 PMCID: PMC5471687 DOI: 10.1186/s40101-017-0142-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 06/01/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Despite the fact that insertions/deletions (INDELs) are the second most common type of genetic variations and variable number tandem repeats (VNTRs) represent a large portion of the human genome, they have received far less attention than single nucleotide polymorphisms (SNPs) and larger forms of structural variation like copy number variations (CNVs), especially in genome-wide association studies (GWAS) of complex diseases like polygenic obesity. This is exemplified by the vast amount of review papers on the role of SNPs and CNVs in obesity, its related traits (like anthropometric measurements, biochemical variables, and eating behavior), and its related complications (like hypertension, hypertriglyceridemia, hypercholesterolemia, and insulin resistance-collectively known as metabolic syndrome). Hence, this paper reviews the types of INDELs and VNTRs that have been studied for association with obesity and its related traits and complications. These INDELs and VNTRs could be found in the obesity loci or genes from the earliest GWAS and candidate gene association studies, like FTO, genes in the leptin-proopiomelanocortin pathway, and UCP2/3. Given the important role of the brain serotonergic and dopaminergic reward system in obesity susceptibility, the association of INDELs and VNTRs in these neurotransmitters' metabolism and transport genes with obesity is also reviewed. Next, the role of INS VNTR in obesity and its related traits is questionable, since recent large-scale studies failed to replicate the earlier positive associations. As obesity results in chronic low-grade inflammation of the adipose tissue, the proinflammatory cytokine gene IL1RA and anti-inflammatory cytokine gene IL4 have VNTRs that are implicated in obesity. A systemic proinflammatory state in combination with activation of the renin-angiotensin system and decreased nitric oxide bioavailability as found in obesity leads to endothelial dysfunction. This explains why VNTR and INDEL in eNOS and ACE, respectively, could be predisposing factors of obesity. Finally, two novel genes, DOCK5 and PER3, which are involved in the regulation of the Akt/MAPK pathway and circadian rhythm, respectively, have VNTRs and INDEL that might be associated with obesity. SHORT CONCLUSION In conclusion, INDELs and VNTRs could have important functional consequences in the pathophysiology of obesity, and research on them should be continued to facilitate obesity prediction, prevention, and treatment.
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Affiliation(s)
- Yee-How Say
- Department of Biomedical Science, Faculty of Science, Universiti Tunku Abdul Rahman (UTAR) Kampar Campus, Jalan Universiti, Bandar Barat, 31900, Kampar, Perak, Malaysia.
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Lanza HI, Pittman P, Batshoun J. Obesity and Cigarette Smoking: Extending the Link to E-cigarette/Vaping Use. Am J Health Behav 2017; 41:338-347. [PMID: 28376978 DOI: 10.5993/ajhb.41.3.13] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVES In recent years, electronic tobacco (e-cigarette/vaping) use among young adults has grown exponentially. Given past research linking obesity and cigarette smoking, assessing whether this relationship extends to electronic tobacco use is warranted. The current study examined weight status as a correlate of substance use patterns reflecting electronic tobacco use. METHODS Survey data were collected from a convenience sample of 452 (59% female) undergraduates attending a large, public university during the 2015-2016 academic year. Latent class analysis (LCA) was conducted to identify substance use classes and examine weight status as a covariate of class membership. RESULTS LCA analyses identified 4 classes: High Substance Use (19%), Risky Alcohol Use (14%), Cigarette/Electronic Tobacco Use (17%), and Low Substance Use (50%). Both obesity status and greater deviation from one's group body mass index (BMI) norm were associated with a higher likelihood of belonging to the Cigarette/Electronic Tobacco Use class. CONCLUSIONS Findings suggest that electronic tobacco use may fit well into previously established relationships between higher weight status and tobacco use. Future research should examine the longitudinal processes and pathways underlying the relationship between weight status and electronic tobacco use.
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Affiliation(s)
- H. Isabella Lanza
- Assistant Professor, Undergraduate Research Assistant, Department of Human Development, California State University, Long Beach, CA;,
| | - Patricia Pittman
- Undergraduate Research Assistant, Department of Human Development, California State University, Long Beach, CA
| | - Jennifer Batshoun
- Undergraduate Research Assistant, Department of Human Development, California State University, Long Beach, CA
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Lanza HI, Grella CE, Chung PJ. Does adolescent weight status predict problematic substance use patterns? Am J Health Behav 2014; 38:708-16. [PMID: 24933140 DOI: 10.5993/ajhb.38.5.8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVES To identify underlying patterns of cigarette smoking, alcohol use, and marijuana use in young adulthood, and ascertain whether adolescent overweight or obesity status predicts problematic substance use patterns. METHODS The study included 15,119 participants from the National Longitudinal Study of Adolescent Health (Add Health) at Wave 1 (11-19 years) and Wave 3 (18-26 years). Latent class analysis was conducted. RESULTS Participants were classified into a Low Substance Use (35%), Regular Smokers (12%), High-risk Alcohol use (33%), or High Substance Use (20%) class. Overweight/obese adolescents had a greater likelihood of belonging to the Regular Smokers class. CONCLUSIONS Overweight/obese adolescents are at higher risk of engaging in regular cigarette smoking without problematic alcohol or marijuana use.
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Affiliation(s)
- H Isabella Lanza
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, USA.
| | - Christine E Grella
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, USA
| | - Paul J Chung
- Department of Pediatrics, University of California, Los Angeles, USA
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Alsiö J, Rask-Andersen M, Chavan RA, Olszewski PK, Levine AS, Fredriksson R, Schiöth HB. Exposure to a high-fat high-sugar diet causes strong up-regulation of proopiomelanocortin and differentially affects dopamine D1 and D2 receptor gene expression in the brainstem of rats. Neurosci Lett 2014; 559:18-23. [DOI: 10.1016/j.neulet.2013.11.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 11/01/2013] [Accepted: 11/11/2013] [Indexed: 11/28/2022]
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Goldfield GS, Dowler LM, Walker M, Cameron JD, Ferraro ZM, Doucet E, Adamo KB. Are dopamine-related genotypes risk factors for excessive gestational weight gain? Int J Womens Health 2013; 5:253-9. [PMID: 23723720 PMCID: PMC3665497 DOI: 10.2147/ijwh.s43935] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Background Excessive gestational weight gain is associated with postpartum weight retention and downstream child obesity. Dopamine plays a critical role in the regulation of energy intake and body weight. The purpose of this study was to examine the relationship between excessive gestational weight gain and dopamine pathway-related polymorphisms, namely the variable nucleotide tandem repeat in the 3′untranslated region (UTR) region of the SLC6A3 (DAT-1) dopamine transporter gene and the 30-base pair variable nucleotide tandem repeat polymorphism of the 5′UTR of the monoamine oxidase-A (MAO-A) gene. Methods Ninety-three women of mean age 31.7 ± 4.2 years were recruited from the Ottawa and Kingston birth cohort and assessed at 12–20 weeks’ gestation. Mean body mass index was 22.7 ± 2.5 kg/m2. Excessive gestational weight gain was defined according to the 2009 Institute of Medicine guidelines based on body mass index. Genotype analyses were performed using polymerase chain reaction and agarose gel electrophoresis. Results There was no relationship between the prevalence or magnitude of excessive gestational weight gain among women with the 3′ UTR single nucleotide polymorphism of the DAT-1 gene. However, 70% (19 of 27) of women carrying the MAO-A 4/4 (high activity) allele exceeded recommendations for gestational weight gain compared with 48% (32 of 60) of those with the pooled 3/3, 3/4, and 3/3.5 (low activity) alleles (P < 0.05). Similarly, those with the MAO-A 4/4 allele had significantly greater gestational weight gain than those with the 3/3, 3/4, or 3/3.5 pooled genotypes (19.3 ± 4.1 versus 17.0 ± 5.0 kg, P = 0.03). Conclusion Carriers of the 4/4 variants of the MAO-A gene may be at increased risk for excessive gestational weight gain.
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Affiliation(s)
- Gary S Goldfield
- Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada ; Department of Paediatrics, University of Ottawa, Ottawa, ON, Canada ; School of Human Kinetics, University of Ottawa, Ottawa, ON, Canada ; School of Psychology, University of Ottawa, Ottawa, ON, Canada ; Department of Psychology, Carleton University, Ottawa, ON, Canada
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van de Giessen E, Hesse S, Caan MWA, Zientek F, Dickson JC, Tossici-Bolt L, Sera T, Asenbaum S, Guignard R, Akdemir UO, Knudsen GM, Nobili F, Pagani M, Vander Borght T, Van Laere K, Varrone A, Tatsch K, Booij J, Sabri O. No association between striatal dopamine transporter binding and body mass index: a multi-center European study in healthy volunteers. Neuroimage 2012; 64:61-7. [PMID: 22982354 DOI: 10.1016/j.neuroimage.2012.09.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 08/30/2012] [Accepted: 09/02/2012] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION Dopamine is one among several neurotransmitters that regulate food intake and overeating. Thus, it has been linked to the pathophysiology of obesity and high body mass index (BMI). Striatal dopamine D(2) receptor availability is lower in obesity and there are indications that striatal dopamine transporter (DAT) availability is also decreased. In this study, we tested whether BMI and striatal DAT availability are associated. METHODS The study included 123 healthy individuals from a large European multi-center database. They had a BMI range of 18.2-41.1 kg/m(2) and were scanned using [(123)I]FP-CIT SPECT imaging. Scans were analyzed with both region-of-interest and voxel-based analysis to determine the binding potential for DAT availability in the caudate nucleus and putamen. A direct relation between BMI and DAT availability was assessed and groups with high and low BMI were compared for DAT availability. RESULTS No association between BMI and striatal DAT availability was found. CONCLUSION The lack of an association between BMI and striatal DAT availability suggests that the regulation of striatal synaptic dopamine levels by DAT plays no or a limited role in the pathophysiology of overweight and obesity.
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Affiliation(s)
- Elsmarieke van de Giessen
- Department of Nuclear Medicine, Academic Medical Center University of Amsterdam, Amsterdam, The Netherlands.
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Snyder EE, Walts B, Pérusse L, Chagnon YC, Weisnagel SJ, Rankinen T, Bouchard C. The Human Obesity Gene Map: The 2003 Update. ACTA ACUST UNITED AC 2012; 12:369-439. [PMID: 15044658 DOI: 10.1038/oby.2004.47] [Citation(s) in RCA: 207] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This is the tenth update of the human obesity gene map, incorporating published results up to the end of October 2003 and continuing the previous format. Evidence from single-gene mutation obesity cases, Mendelian disorders exhibiting obesity as a clinical feature, quantitative trait loci (QTLs) from human genome-wide scans and animal crossbreeding experiments, and association and linkage studies with candidate genes and other markers is reviewed. Transgenic and knockout murine models relevant to obesity are also incorporated (N = 55). As of October 2003, 41 Mendelian syndromes relevant to human obesity have been mapped to a genomic region, and causal genes or strong candidates have been identified for most of these syndromes. QTLs reported from animal models currently number 183. There are 208 human QTLs for obesity phenotypes from genome-wide scans and candidate regions in targeted studies. A total of 35 genomic regions harbor QTLs replicated among two to five studies. Attempts to relate DNA sequence variation in specific genes to obesity phenotypes continue to grow, with 272 studies reporting positive associations with 90 candidate genes. Fifteen such candidate genes are supported by at least five positive studies. The obesity gene map shows putative loci on all chromosomes except Y. Overall, more than 430 genes, markers, and chromosomal regions have been associated or linked with human obesity phenotypes. The electronic version of the map with links to useful sites can be found at http://obesitygene.pbrc.edu.
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Affiliation(s)
- Eric E Snyder
- Human Genomics Laboratory, Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, Louisiana 70808-4124, USA
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Pérusse L, Rankinen T, Zuberi A, Chagnon YC, Weisnagel SJ, Argyropoulos G, Walts B, Snyder EE, Bouchard C. The Human Obesity Gene Map: The 2004 Update. ACTA ACUST UNITED AC 2012; 13:381-490. [PMID: 15833932 DOI: 10.1038/oby.2005.50] [Citation(s) in RCA: 212] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This paper presents the eleventh update of the human obesity gene map, which incorporates published results up to the end of October 2004. Evidence from single-gene mutation obesity cases, Mendelian disorders exhibiting obesity as a clinical feature, transgenic and knockout murine models relevant to obesity, quantitative trait loci (QTLs) from animal cross-breeding experiments, association studies with candidate genes, and linkages from genome scans is reviewed. As of October 2004, 173 human obesity cases due to single-gene mutations in 10 different genes have been reported, and 49 loci related to Mendelian syndromes relevant to human obesity have been mapped to a genomic region, and causal genes or strong candidates have been identified for most of these syndromes. There are 166 genes which, when mutated or expressed as transgenes in the mouse, result in phenotypes that affect body weight and adiposity. The number of QTLs reported from animal models currently reaches 221. The number of human obesity QTLs derived from genome scans continues to grow, and we have now 204 QTLs for obesity-related phenotypes from 50 genome-wide scans. A total of 38 genomic regions harbor QTLs replicated among two to four studies. The number of studies reporting associations between DNA sequence variation in specific genes and obesity phenotypes has also increased considerably with 358 findings of positive associations with 113 candidate genes. Among them, 18 genes are supported by at least five positive studies. The obesity gene map shows putative loci on all chromosomes except Y. Overall, >600 genes, markers, and chromosomal regions have been associated or linked with human obesity phenotypes. The electronic version of the map with links to useful publications and genomic and other relevant sites can be found at http://obesitygene.pbrc.edu.
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Affiliation(s)
- Louis Pérusse
- Division of Kinesiology, Department of Social and Preventive Medicine, Faculty of Medicine, Laval University, Sainte-Foy, Québec, Canada
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Egecioglu E, Skibicka KP, Hansson C, Alvarez-Crespo M, Friberg PA, Jerlhag E, Engel JA, Dickson SL. Hedonic and incentive signals for body weight control. Rev Endocr Metab Disord 2011; 12:141-51. [PMID: 21340584 PMCID: PMC3145094 DOI: 10.1007/s11154-011-9166-4] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Here we review the emerging neurobiological understanding of the role of the brain's reward system in the regulation of body weight in health and in disease. Common obesity is characterized by the over-consumption of palatable/rewarding foods, reflecting an imbalance in the relative importance of hedonic versus homeostatic signals. The popular 'incentive salience theory' of food reward recognises not only a hedonic/pleasure component ('liking') but also an incentive motivation component ('wanting' or 'reward-seeking'). Central to the neurobiology of the reward mechanism is the mesoaccumbal dopamine system that confers incentive motivation not only for natural rewards such as food but also by artificial rewards (eg. addictive drugs). Indeed, this mesoaccumbal dopamine system receives and integrates information about the incentive (rewarding) value of foods with information about metabolic status. Problematic over-eating likely reflects a changing balance in the control exerted by hypothalamic versus reward circuits and/or it could reflect an allostatic shift in the hedonic set point for food reward. Certainly, for obesity to prevail, metabolic satiety signals such as leptin and insulin fail to regain control of appetitive brain networks, including those involved in food reward. On the other hand, metabolic control could reflect increased signalling by the stomach-derived orexigenic hormone, ghrelin. We have shown that ghrelin activates the mesoaccumbal dopamine system and that central ghrelin signalling is required for reward from both chemical drugs (eg alcohol) and also from palatable food. Future therapies for problematic over-eating and obesity may include drugs that interfere with incentive motivation, such as ghrelin antagonists.
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Affiliation(s)
- Emil Egecioglu
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - Karolina P. Skibicka
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - Caroline Hansson
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - Mayte Alvarez-Crespo
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - P. Anders Friberg
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - Jörgen A. Engel
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
| | - Suzanne L. Dickson
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, PO Box 434, SE-405 30 Gothenburg, Sweden
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Genotype and ancestry modulate brain's DAT availability in healthy humans. PLoS One 2011; 6:e22754. [PMID: 21826203 PMCID: PMC3149615 DOI: 10.1371/journal.pone.0022754] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 06/30/2011] [Indexed: 12/18/2022] Open
Abstract
The dopamine transporter (DAT) is a principal regulator of dopaminergic neurotransmission and its gene (the SLC6A3) is a strong biological candidate gene for various behavioral- and neurological disorders. Intense investigation of the link between the SLC6A3 polymorphisms and behavioral phenotypes yielded inconsistent and even contradictory results. Reliance on objective brain phenotype measures, for example, those afforded by brain imaging, might critically improve detection of DAT genotype-phenotype association. Here, we tested the relationship between the DAT brain availability and the SLC6A3 genotypes using an aggregate sample of 95 healthy participants of several imaging studies. These studies employed positron emission tomography (PET) with [¹¹C]cocaine wherein the DAT availability was estimated as Bmax/Kd; while the genotype values were obtained on two repeat polymorphisms--3-UTR- and intron 8--VNTRs. The main findings are the following: 1) both polymorphisms analyzed as single genetic markers and in combination (haplotype) modulate DAT density in midbrain; 2) ethnic background and age influence the strength of these associations; and 3) age-related changes in DAT availability differ in the 3-UTR and intron 8--genotype groups.
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Dopamine polymorphisms and depressive symptoms predict foods intake. Results from a nationally representative sample. Appetite 2011; 57:339-48. [PMID: 21672565 DOI: 10.1016/j.appet.2011.05.325] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 05/12/2011] [Accepted: 05/28/2011] [Indexed: 11/24/2022]
Abstract
Depression and variation in dopamine related genes have both independently been associated with food consumption. Depressive symptoms could synergistically interact with genetic variation to influence food intake. We examined the interaction between high depressive symptoms and functional polymorphisms of dopamine transporter (SLC6A3), monoamine oxidase A (MAOA), dopamine receptor D2 (DRD2) and dopamine receptor D4 (DRD4) on intake of high-calorie sweet, high-calorie non-sweet, and low-calorie foods in the National Longitudinal Study of Adolescent Health (Add Health). Multivariate linear regression analyses were used to examine main effects of gene and depression symptoms and their interaction (genotype-by-high depression symptoms) on food categories. Applying a false discovery rate criterion for multiple comparisons indicated a statistically significant interaction for females with high depressive symptoms and the SLC6A3 gene, such that those with the SLC6A3 10/10 allele reported greater intake of high-calorie sweet foods than their counterparts high in depressive symptoms with the SLC6A3 any 9 allele (LS mean 10/10 allele=2.5, SE=.13; LS mean any 9 allele=1.8, SE=.13, p<.05). These findings highlight that the relationship between depression and food intake may vary as a function of genetic polymorphism. Further research is needed to confirm these findings.
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Stice E, Yokum S, Zald D, Dagher A. Dopamine-based reward circuitry responsivity, genetics, and overeating. Curr Top Behav Neurosci 2011; 6:81-93. [PMID: 21243471 DOI: 10.1007/7854_2010_89] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Data suggest that low levels of dopamine D2 receptors and attenuated responsivity of dopamine-target regions to food intake is associated with increased eating and elevated weight. There is also growing (although mixed) evidence that genotypes that appear to lead to reduced dopamine signaling (e.g., DRD2, DRD4, and DAT) and certain appetite-related hormones and peptides (e.g., ghrelin, orexin A, leptin) moderate the relation between dopamine signaling, overeating, and obesity. This chapter reviews findings from studies that have investigated the relation between dopamine functioning and food intake and how certain genotypes and appetite-related hormones and peptides affect this relation.
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Affiliation(s)
- Eric Stice
- Oregon Research Institute, Eugene, OR, USA.
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Panariello F, De Luca V, de Bartolomeis A. Weight gain, schizophrenia and antipsychotics: new findings from animal model and pharmacogenomic studies. SCHIZOPHRENIA RESEARCH AND TREATMENT 2010; 2011:459284. [PMID: 22988505 PMCID: PMC3440684 DOI: 10.1155/2011/459284] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/03/2010] [Revised: 08/03/2010] [Accepted: 10/24/2010] [Indexed: 02/07/2023]
Abstract
Excess body weight is one of the most common physical health problems among patients with schizophrenia that increases the risk for many medical problems, including type 2 diabetes mellitus, coronary heart disease, osteoarthritis, and hypertension, and accounts in part for 20% shorter life expectancy than in general population. Among patients with severe mental illness, obesity can be attributed to an unhealthy lifestyle, personal genetic profile, as well as the effects of psychotropic medications, above all antipsychotic drugs. Novel "atypical" antipsychotic drugs represent a substantial improvement on older "typical" drugs. However, clinical experience has shown that some, but not all, of these drugs can induce substantial weight gain. Animal models of antipsychotic-related weight gain and animal transgenic models of knockout or overexpressed genes of antipsychotic receptors have been largely evaluated by scientific community for changes in obesity-related gene expression or phenotypes. Moreover, pharmacogenomic approaches have allowed to detect more than 300 possible candidate genes for antipsychotics-induced body weight gain. In this paper, we summarize current thinking on: (1) the role of polymorphisms in several candidate genes, (2) the possible roles of various neurotransmitters and neuropeptides in this adverse drug reaction, and (3) the state of development of animal models in this matter. We also outline major areas for future research.
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Affiliation(s)
- Fabio Panariello
- Department of Psychiatry, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Room 30, Toronto, ON, Canada M5T 1R8
| | - Vincenzo De Luca
- Department of Psychiatry, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Room 30, Toronto, ON, Canada M5T 1R8
| | - Andrea de Bartolomeis
- Dipartimento di Neuroscienze, Sezione di Psichiatria, Laboratorio di Psichiatria Molecolare, University of Napoli “Federico II”, Via Pansini 5, 80131 Napoli, Italy
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16
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Dopamine D1 receptor gene expression decreases in the nucleus accumbens upon long-term exposure to palatable food and differs depending on diet-induced obesity phenotype in rats. Neuroscience 2010; 171:779-87. [DOI: 10.1016/j.neuroscience.2010.09.046] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 09/14/2010] [Accepted: 09/27/2010] [Indexed: 11/18/2022]
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Johansson A, Marroni F, Hayward C, Franklin CS, Kirichenko AV, Jonasson I, Hicks AA, Vitart V, Isaacs A, Axenovich T, Campbell S, Floyd J, Hastie N, Knott S, Lauc G, Pichler I, Rotim K, Wild SH, Zorkoltseva IV, Wilson JF, Rudan I, Campbell H, Pattaro C, Pramstaller P, Oostra BA, Wright AF, van Duijn CM, Aulchenko YS, Gyllensten U. Linkage and genome-wide association analysis of obesity-related phenotypes: association of weight with the MGAT1 gene. Obesity (Silver Spring) 2010; 18:803-8. [PMID: 19851299 DOI: 10.1038/oby.2009.359] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
As major risk-factors for diabetes and cardiovascular diseases, the genetic contribution to obesity-related traits has been of interest for decades. Recently, a limited number of common genetic variants, which have replicated in different populations, have been identified. One approach to increase the statistical power in genetic mapping studies is to focus on populations with increased levels of linkage disequilibrium (LD) and reduced genetic diversity. We have performed joint linkage and genome-wide association analyses for weight and BMI in 3,448 (linkage) and 3,925 (association) partly overlapping healthy individuals from five European populations. A total of four chromosomal regions (two for weight and two for BMI) showed suggestive linkage (lod >2.69) either in one of the populations or in the joint data. At the genome-wide level (nominal P < 1.6 x 10(-7), Bonferroni-adjusted P < 0.05) one single-nucleotide polymorphism (SNP) (rs12517906) (nominal P = 7.3 x 10(-8)) was associated with weight, whereas none with BMI. The SNP associated with weight is located close to MGAT1. The monoacylglycerol acyltransferase (MGAT) enzyme family is known to be involved in dietary fat absorption. There was no overlap between the linkage regions and the associated SNPs. Our results show that genetic effects influencing weight and BMI are shared across diverse European populations, even though some of these populations have experienced recent population bottlenecks and/or been affected by genetic drift. The analysis enabled us to identify a new candidate gene, MGAT1, associated with weight in women.
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Affiliation(s)
- Asa Johansson
- Department of Genetics and Pathology, Rudbeck laboratory, Uppsala University, Uppsala, Sweden
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18
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Body mass index and smoking: cross-sectional study of a representative sample of adolescents in Denmark. Int J Public Health 2010; 55:307-14. [PMID: 20094754 DOI: 10.1007/s00038-009-0115-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2009] [Revised: 08/23/2009] [Accepted: 11/15/2009] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE To quantify the association between body mass index (BMI) and smoking (at all and daily smoking) stratified by gender, family social class, and ethnicity among adolescents aged between 13 and 15. METHODS The analyses were based on the Danish contribution to the international Health Behaviour in School-aged Children survey in 2002 with self-reported data on height, weight, and smoking behaviour. The study population comprised 3,072 students aged between 13 and 15 (1,512 boys and 1,560 girls). Logistic regression analysis was used to quantify the association. RESULTS Odds of at all smoking by BMI (per step) was 1.10 (95% CI 1.03-1.17) among boys but there was no association among girls (OR 0.98, 95% CI 0.93-1.04). No significant association was found for daily smoking and BMI. The association between at all smoking and BMI (per step) was significant among boys of middle social class (OR 1.13, 95% CI 1.03-1.24) and Danish ethnicity (OR 1.10, 95% CI 1.02-1.19). CONCLUSION Significant association exists between smoking and BMI among boys of Danish ethnicity and middle family social class only.
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19
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Stice E, Spoor S, Ng J, Zald DH. Relation of obesity to consummatory and anticipatory food reward. Physiol Behav 2009; 97:551-60. [PMID: 19328819 PMCID: PMC2734415 DOI: 10.1016/j.physbeh.2009.03.020] [Citation(s) in RCA: 199] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2008] [Revised: 03/15/2009] [Accepted: 03/16/2009] [Indexed: 10/21/2022]
Abstract
This report reviews findings from studies that have investigated whether abnormalities in reward from food intake and anticipated food intake increase risk for obesity. Self-report and behavioral data suggest that obese relative to lean individuals show elevated anticipatory and consummatory food reward. Brain imaging studies suggest that obese relative to lean individuals show greater activation of the gustatory cortex (insula/frontal operculum) and oral somatosensory regions (parietal operculum and Rolandic operculum) in response to anticipated intake and consumption of palatable foods. Yet, data also suggest that obese relative to lean individuals show less activation in the dorsal striatum in response to consumption of palatable foods and reduced striatal D2 dopamine receptor density. Emerging prospective data also suggest that abnormal activation in these brain regions increases risk for future weight gain and that genotypes associated with lowered dopamine signaling amplify these predictive effects. Results imply that individuals who show greater activation in the gustatory cortex and somatosensory regions in response to anticipation and consumption of food, but who show weaker activation in the striatum during food intake, may be at risk for overeating, particularly those at genetic risk for lowered dopamine receptor signaling.
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Affiliation(s)
- Eric Stice
- Oregon Research Institute, Eugene, OR 97403, USA.
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20
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Leddy JJ, Waxmonsky JG, Salis RJ, Paluch RA, Gnagy EM, Mahaney P, Erbe R, Pelham WE, Epstein LH. Dopamine-related genotypes and the dose-response effect of methylphenidate on eating in attention-deficit/hyperactivity disorder youths. J Child Adolesc Psychopharmacol 2009; 19:127-36. [PMID: 19364291 DOI: 10.1089/cap.2008.046] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE There are individual differences in the effects of methylphenidate (MPH), a dopamine (DA) transport inhibitor, on appetite in children with attention-deficit/hyperactivity disorder (ADHD). One potential moderating factor is variation in brain DA activity, which is influenced by dopamine-related genes: the DA transporter (DAT) (SLC6A3), the DA D2 receptor (DRD2), and the DA D4 receptor (DRD4) genes. The purpose of this study was to explore the relationship between dopamine-related gene polymorphisms and food consumption in ADHD children receiving varying doses of MPH. METHODS In a randomized, within-subject, double-blind design, 58 ADHD children (ages 6-12 years) received placebo, 0.15, 0.3, or 0.6 mg/kg of MPH three times daily over 9 weeks. Observations of percent lunch consumed as a function of dopamine-related genotypes and MPH dose were analyzed using mixed effects regression models. RESULTS A significant dose-response reduction in eating was observed across all genotypes (p < 0.001). There was an interaction of DAT SLC6A3 and DRD2 genotypes and dose, because 9/9 DAT children showed a stronger effect of dose when compared with the 9/10 and 10/10 children (p < 0.001) and DRD2 A2/A2 children showed a stronger effect of dose when compared with A1/A1 and A1/A2 children combined (p = 0.007). There was no significant interaction of dose by DRD4 genotype. CONCLUSIONS Lunch consumption decreased as a function of MPH dose. DA-related genotypes associated with greater brain DA signaling moderated the influence of drug on consumption. These results provide information relevant to predicting which children are likely to experience the greatest appetite suppression when taking MPH.
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Affiliation(s)
- John J Leddy
- State University of New York at Buffalo School of Medicine and Biomedical Sciences, Buffalo, New York, USA.
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21
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Azzato EM, Morton LM, Bergen AW, Wang SS, Chatterjee N, Kvale P, Yeager M, Hayes RB, Chanock SJ, Caporaso NE. SLC6A3 and body mass index in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. BMC MEDICAL GENETICS 2009; 10:9. [PMID: 19183461 PMCID: PMC2640369 DOI: 10.1186/1471-2350-10-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 01/30/2009] [Indexed: 11/29/2022]
Abstract
Background To investigate the contribution of the dopamine transporter to dopaminergic reward-related behaviors and anthropometry, we evaluated associations between polymorphisms at the dopamine transporter gene(SLC6A3) and body mass index (BMI), among participants in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. Methods Four polymorphisms (rs6350, rs6413429, rs6347 and the 3' variable number of tandem repeat (3' VNTR) polymorphism) at the SLC6A3 gene were genotyped in 2,364 participants selected from the screening arm of PLCO randomly within strata of sex, age and smoking history. Height and weight at ages 20 and 50 years and baseline were assessed by questionnaire. BMI was calculated and categorized as underweight, normal, overweight and obese (<18.5, 18.5–24.9, 25.0–29.9, or ≥ 30 kg/m2, respectively). Odds ratios (ORs) and 95% confidence intervals (CIs) of SLC6A3 genotypes and haplotypes were computed using conditional logistic regression. Results Compared with individuals having a normal BMI, obese individuals at the time of the baseline study questionnaire were less likely to possess the 3' VNTR variant allele with 9 copies of the repeated sequence in a dose-dependent model (** is referent; OR*9 = 0.80, OR99 = 0.47, ptrend = 0.005). Compared with individuals having a normal BMI at age 50, overweight individuals (A-C-G-* is referent; ORA-C-G-9 = 0.80, 95% CI 0.65–0.99, p = 0.04) and obese individuals (A-C-G-* is referent; ORA-C-G-9 = 0.70, 95% CI 0.49–0.99, p = 0.04) were less likely to possess the haplotype with the 3'variant allele (A-C-G-9). Conclusion Our results support a role of genetic variation at the dopamine transporter gene, SLC6A3, as a modifier of BMI.
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Affiliation(s)
- Elizabeth M Azzato
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, Maryland, USA.
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Need AC, Ahmadi KR, Spector TD, Goldstein DB. Obesity is Associated with Genetic Variants That Alter Dopamine Availability. Ann Hum Genet 2008; 70:293-303. [PMID: 16674552 DOI: 10.1111/j.1529-8817.2005.00228.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Human and animal studies have implicated dopamine in appetite regulation, and family studies have shown that BMI has a strong genetic component. Dopamine availability is controlled largely by three enzymes: COMT, MAOA and MAOB, and by the dopamine transporter SLC6A3, and each gene has a well-characterized functional variant. Here we look at these four functional polymorphisms together, to investigate how heritable variation in dopamine levels influences the risk of obesity in a cohort of 1150, including 240 defined as obese (BMI > or = 30). The COMT and SLC6A3 polymorphisms showed no association with either weight, BMI or obesity risk. We found, however, that both MAOA and MAOB show an excess of the low-activity genotypes in obese individuals (MAOA:chi2= 15.45, p = 0.004; MAOB:chi2= 8.05, p = 0.018). Additionally, the MAOA genotype was significantly associated with both weight (p = 0.0005) and BMI (p = 0.001). When considered together, the 'at risk genotype'--low activity genotypes at both the MAOA and MAOB loci--shows a relative risk for obesity of 5.01. These results have not been replicated and, given the experience of complex trait genetics, warrant caution in interpretation. In implicating both the MAOA and MOAB variants, however, this study provides the first indication that dopamine availability (as opposed to other effects of MAOA) is involved in human obesity. It is therefore a priority to assess the associations in replication datasets.
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Affiliation(s)
- A C Need
- Department of Biology, University College London, The Darwin Building, Gower Street, London WC1E 6BT
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23
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Schmitt AO, Al-Hasani H, Cheverud JM, Pomp D, Bünger L, Brockmann GA. Fine mapping of mouse QTLs for fatness using SNP data. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2008; 11:341-50. [PMID: 18092907 DOI: 10.1089/omi.2007.0015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Quantitative trait loci (QTLs), as determined in crossbred studies, are a valuable resource to identify genes responsible for the corresponding phenotypic variances. Due to their broad chromosomal extension of some dozens of megabases, further steps are necessary to bring the number of candidate genes that underlie the detected effects to a reasonable order of magnitude. We use a set of 13,370 SNPs to identify informative haplotype blocks in 22 mouse QTLs for fatness. About half of the genes in a typical QTL overlap with haplotype blocks, which are different for the two base mouse lines, and which, thus, qualify for further analysis. For these genes we collect four more pieces of evidence for association with fat accumulation, namely (1) homology to genes identified in a Caenorhabditis elegans knock-out experiment as fat decreasing or fat increasing, (2) the overexpression of the genes in mouse fat, liver, muscle, or hypothalamus tissues, (3) the occurrence of a gene in several independently found QTLs, and (4) the information provided by gene ontology, to achieve a ranked list of 131 candidate genes. Ten genes fulfill three or four of the above sketched criteria and are discussed briefly, 121 further genes fulfilling two criteria are provided as on-line material. Viewing the genomic region of fatness-related QTLs under several different aspects is appropriate to assess the many thousands of genes that reside in such QTLs and to produce lists of more robust candidate genes.
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Affiliation(s)
- Armin O Schmitt
- Institute for Animal Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.
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24
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Fuemmeler BF, Agurs-Collins TD, McClernon FJ, Kollins SH, Kail ME, Bergen AW, Ashley-Koch AE. Genes implicated in serotonergic and dopaminergic functioning predict BMI categories. Obesity (Silver Spring) 2008; 16:348-55. [PMID: 18239643 PMCID: PMC2919156 DOI: 10.1038/oby.2007.65] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE This study addressed the hypothesis that variation in genes associated with dopamine function (SLC6A3, DRD2, DRD4), serotonin function (SLC6A4, and regulation of monoamine levels (MAOA) may be predictive of BMI categories (obese and overweight + obese) in young adulthood and of changes in BMI as adolescents transition into young adulthood. Interactions with gender and race/ethnicity were also examined. METHODS AND PROCEDURES Participants were a subsample of individuals from the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative sample of adolescents followed from 1995 to 2002. The sample analyzed included a subset of 1,584 unrelated individuals with genotype data. Multiple logistic regressions were conducted to evaluate the associations between genotypes and obesity (BMI > 29.9) or overweight + obese combined (BMI > or = 25) with normal weight (BMI = 18.5-24.9) as a referent. Linear regression models were used to examine change in BMI from adolescence to young adulthood. RESULTS Significant associations were found between SLC6A4 5HTTLPR and categories of BMI, and between MAOA promoter variable number tandem repeat (VNTR) among men and categories of BMI. Stratified analyses revealed that the association between these two genes and excess BMI was significant for men overall and for white and Hispanic men specifically. Linear regression models indicated a significant effect of SLC6A4 5HTTLPR on change in BMI from adolescence to young adulthood. DISCUSSION Our findings lend further support to the involvement of genes implicated in dopamine and serotonin regulation on energy balance.
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Affiliation(s)
- Bernard F Fuemmeler
- Department of Community and Family Medicine, Duke University Medical Center, Durham, NC, USA.
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25
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Davis C, Levitan RD, Kaplan AS, Carter J, Reid C, Curtis C, Patte K, Kennedy JL. Dopamine transporter gene (DAT1) associated with appetite suppression to methylphenidate in a case-control study of binge eating disorder. Neuropsychopharmacology 2007; 32:2199-206. [PMID: 17314918 DOI: 10.1038/sj.npp.1301348] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Response to psychomotor stimulants is highly variable across individuals. Such inconsistencies are influenced by many factors including drug dose and polymorphic differences in genes that encode proteins, such as the dopamine transporter (DAT1), which are relevant to the site of action of these substances. The current study used a double blind, crossover (methylphenidate vs placebo) design to assess DAT1 genotype differences on appetite ratings to a snack-food cue in subjects with binge eating disorder (BED) (n=32) and healthy age-matched controls (n=46). ANOVA results indicated a significant genotype x diagnostic group interaction whereby BED subjects with at least one copy of the 9-repeat allele showed a significant suppression of appetite in response to methylphenidate compared with controls with this allele, or to subjects with the 10/10 genotype (irrespective of diagnosis) whose drug response was indistinguishable from placebo. The most probable explanation for these findings is that some, currently unknown, genetic variant, which is overrepresented in those with BED, interacts with DAT1 to suppress appetite in response to stimulant administration. The current findings have implications for treatment response to drugs currently in use (or being developed) for the treatment of overeating and overweight.
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Affiliation(s)
- Caroline Davis
- Department of Kinesiology and Health Sciences, York University, Toronto, ON, Canada.
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26
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Goldfield GS, Lorello C, Doucet E. Methylphenidate reduces energy intake and dietary fat intake in adults: a mechanism of reduced reinforcing value of food? Am J Clin Nutr 2007; 86:308-15. [PMID: 17684199 DOI: 10.1093/ajcn/86.2.308] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Dopamine mediates the reinforcing value of food, and low concentrations of dopamine are related to increased feeding. Thus, administering a drug that increases dopamine may reduce energy intake, possibly by reducing food reinforcement. OBJECTIVES We tested whether short-acting methylphenidate (MPH), a drug that increases the availability of dopamine by blocking its reuptake, reduces energy intake and alters macronutrient preference and whether these effects are due to a mechanism of reduced hunger or food reinforcement. DESIGN Fourteen adults were given placebo or short-acting MPH (0.5 mg/kg) in a randomized, double-blind, placebo-controlled crossover fashion. One hour after ingestion, hunger and the relative reinforcing value of snack food were measured, followed immediately by energy intake and macronutrient preference during a buffet-style lunch. RESULTS MPH reduced energy intake by 11% (P = 0.024) as well as intake of fat by 17% (P = 0.003) relative to placebo. Despite similar levels of prebuffet hunger, subjects taking MPH reduced their energy and fat intakes more than did those taking placebo, which suggests that hunger may not mediate the effects of MPH on energy intake. MPH showed a trend toward reducing the reinforcing value of high-fat food relative to placebo, but reduced food reinforcement was not significantly correlated with energy intake. CONCLUSION MPH reduced overall energy intake with a selective reduction in dietary fat. Findings are consistent with a reward deficiency model of obesity whereby low brain dopamine predicts overeating and obesity, and administering agents that increase dopamine results in reduced feeding behavior.
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Affiliation(s)
- Gary S Goldfield
- Mental Health Research, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
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O'Brien LM, Holbrook CR, Faye Jones V, Gozal D. Ethnic difference in periodic limb movements in children. Sleep Med 2007; 8:240-6. [PMID: 17368099 DOI: 10.1016/j.sleep.2006.08.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2006] [Revised: 08/07/2006] [Accepted: 08/14/2006] [Indexed: 11/22/2022]
Abstract
BACKGROUND Epidemiological studies have suggested that ethnicity is a risk factor for sleep-disordered breathing (SDB) and that African-American children are three times more likely than Caucasian children to have SDB. Ethnic differences in sleep architecture and other routinely assessed sleep parameters have not been critically assessed, thus the aim of this study was to compare sleep characteristics in African-American and Caucasian children. METHODS A total of 41,363 sleep questionnaires were mailed to parents of children aged 5-7 years in Jefferson County, KY. Parents of snoring and non-snoring children were invited to have their child undergo overnight polysomnography. RESULTS Complete questionnaires were returned by 9872 families (23% response rate). Of these, 689 agreed to undergo polysomnography, and 542 complete polysomnograms were obtained (5.7% of questionnaire respondents). There were 391 Caucasian and 151 African-American children with a mean age of 6.7+/-0.5 years who underwent overnight polysomnographic evaluation. No differences between groups were observed for sleep latency, total sleep time, sleep efficiency, or rapid eye movement (REM) latency. African-American children had slightly increased stage 3 sleep (6.0+/-2.8% vs. 5.4+/-2.8%; p=0.01), although the total proportion of slow wave sleep was similar. Higher respiratory arousal index (3.6+/-6.5/h vs. 1.4+/-2.7/h; p<0.001) and total arousal index (11.5+/-5.2/h vs. 9.8+/-4.8/h; p<0.001) emerged in African-American children, who were more likely to have mild SDB (AHI>1:34% in African-American vs. 24% in Caucasian; p=0.017) and SDB (AHI>5: 22.5% vs. 7%; p<0.001). However, Caucasian children were more likely to have periodic leg movements during sleep (PLMS; 16.5% vs. 7% in AA; p=0.004). The odds ratio for a Caucasian child to have PLMS was 2.6 (95% confidence interval (CI) 1.3-5.3; p=0.006). Furthermore, in the absence of SDB, the odds ratio for a Caucasian child to have PLMS was 9.5 (95% CI: 2.2-39.9; p=0.002). CONCLUSIONS African-American and Caucasian children have similar sleep architecture. African-American children are more likely to display respiratory disturbances during sleep, while PLMS are significantly more prevalent among Caucasian children.
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Affiliation(s)
- Louise M O'Brien
- Kosair Children's Hospital Research Institute, Division of Pediatric Sleep Medicine, Department of Pediatrics, Louisville, KY 40202, USA
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28
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Munafò MR, Shields AE, Berrettini WH, Patterson F, Lerman C. Pharmacogenetics and nicotine addiction treatment. Pharmacogenomics 2006; 6:211-23. [PMID: 16013953 DOI: 10.1517/14622416.6.3.211] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
This review focuses on the current status of, and future directions for, pharmacogenetic research on nicotine dependence and smoking cessation treatment. Pharmacological treatment involving nicotine replacement therapy and bupropion for nicotine addiction and smoking cessation has been shown to be efficacious when provided in combination with behavioral support. Cessation rates remain somewhat modest, however, and one possibility is that success rates may be enhanced by offering treatments tailored to an individual's genotype. Nonetheless, research on this issue remains in its infancy, and although the scope for individualized treatment tailored to genotype is promising, there are substantial practical, ethical and social considerations that must be addressed before such research is translated into clinical practice.
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Affiliation(s)
- Marcus R Munafò
- University of Bristol, Department of Experimental Psychology, Bristol BS8 ITN, UK.
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29
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Rankinen T, Zuberi A, Chagnon YC, Weisnagel SJ, Argyropoulos G, Walts B, Pérusse L, Bouchard C. The human obesity gene map: the 2005 update. Obesity (Silver Spring) 2006; 14:529-644. [PMID: 16741264 DOI: 10.1038/oby.2006.71] [Citation(s) in RCA: 685] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This paper presents the 12th update of the human obesity gene map, which incorporates published results up to the end of October 2005. Evidence from single-gene mutation obesity cases, Mendelian disorders exhibiting obesity as a clinical feature, transgenic and knockout murine models relevant to obesity, quantitative trait loci (QTL) from animal cross-breeding experiments, association studies with candidate genes, and linkages from genome scans is reviewed. As of October 2005, 176 human obesity cases due to single-gene mutations in 11 different genes have been reported, 50 loci related to Mendelian syndromes relevant to human obesity have been mapped to a genomic region, and causal genes or strong candidates have been identified for most of these syndromes. There are 244 genes that, when mutated or expressed as transgenes in the mouse, result in phenotypes that affect body weight and adiposity. The number of QTLs reported from animal models currently reaches 408. The number of human obesity QTLs derived from genome scans continues to grow, and we now have 253 QTLs for obesity-related phenotypes from 61 genome-wide scans. A total of 52 genomic regions harbor QTLs supported by two or more studies. The number of studies reporting associations between DNA sequence variation in specific genes and obesity phenotypes has also increased considerably, with 426 findings of positive associations with 127 candidate genes. A promising observation is that 22 genes are each supported by at least five positive studies. The obesity gene map shows putative loci on all chromosomes except Y. The electronic version of the map with links to useful publications and relevant sites can be found at http://obesitygene.pbrc.edu.
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Affiliation(s)
- Tuomo Rankinen
- Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808-4124, USA
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Obesity, dopamine and the metabolic syndrome: potential of dopaminergic agents in the control of metabolism. ACTA ACUST UNITED AC 2006. [DOI: 10.1097/01.med.0000216967.74622.9c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Epstein LH, Leddy JJ. Food reinforcement. Appetite 2006; 46:22-5. [PMID: 16257474 DOI: 10.1016/j.appet.2005.04.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2004] [Revised: 01/31/2005] [Accepted: 04/03/2005] [Indexed: 11/17/2022]
Abstract
The reinforcing value of food, measured by how hard someone is willing to work to obtain food, is influenced by food palatability, food deprivation and food variety, and may be a more powerful determinant of food intake than hedonics or liking. The reinforcing value of food is mediated in part by dopaminergic activity. Genotypes that influence dopamine transport and the density of dopamine D2 receptors interact with food reinforcement to influence eating behavior, and D2 receptor genotypes may influence food reinforcement and weight gain after smoking cessation. Inhibition of dopamine transport increases brain dopamine concentrations, which may influence weight gain after smoking cessation and can reduce energy intake in obese adults.
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Affiliation(s)
- Leonard H Epstein
- Department of Pediatrics, University at Buffalo School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Farber Hall, Room G56, 3435 Main Street, Building #26, Buffalo, NY 14214-3000, USA.
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Lerman C, Patterson F, Berrettini W. Treating Tobacco Dependence: State of the Science and New Directions. J Clin Oncol 2005; 23:311-23. [PMID: 15637394 DOI: 10.1200/jco.2005.04.058] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite almost two decades of intensive tobacco control efforts, nearly one quarter of Americans continue to smoke. The two United States Food and Drug Administration–approved medications used to treat tobacco dependence, bupropion and nicotine replacement therapy, are effective for only a fraction of smokers. Investigations of medications approved for affective disorders and other forms of substance abuse, such as fluoxetine and naltrexone, have yielded mixed results as tobacco dependence treatments. A particular challenge in tobacco dependence treatment is the development of effective approaches for smokers with unique needs, such as cancer patients and pregnant women. Despite new developments in these areas, significant gaps in knowledge and practice remain. Basic research in the neurobiologic and genetic basis of nicotine dependence offers promise for the development of novel and more effective treatment approaches. For example, emerging research in pharmacogenetics explores how genetic variation in drug-metabolizing enzymes and drug targets modifies response to pharmacotherapy. These discoveries could someday help practitioners to individualize the type, dosage, and duration of tobacco dependence treatment based on genotype, and maximize the efficacy.
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Affiliation(s)
- Caryn Lerman
- Tobacco Use Research Center, 3535 Market St, Suite 4100, Philadelphia, PA 19104, USA.
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Leddy JJ, Epstein LH, Jaroni JL, Roemmich JN, Paluch RA, Goldfield GS, Lerman C. Influence of methylphenidate on eating in obese men. ACTA ACUST UNITED AC 2004; 12:224-32. [PMID: 14981214 DOI: 10.1038/oby.2004.29] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Rapid synaptic dopamine transport or reduced brain dopamine receptor signaling may influence energy intake. Methylphenidate, a dopamine reuptake inhibitor, increases brain synaptic dopamine and produces anorexia, suggesting that it may reduce energy intake. We investigated the effects of two doses of short-acting methylphenidate on energy intake over one meal in obese adult males. RESEARCH METHODS AND PROCEDURES Nine obese males (>85th BMI percentile) ingested a placebo or a moderate dose (0.5 mg/kg) or a high dose (1.0 mg/kg) of methylphenidate in a within-subject double-blind acute laboratory study. One hour after ingestion, pizza consumption was measured in a naturalistic laboratory setting. RESULTS Participants reduced energy intake by 23% for the moderate dose vs. the placebo (p < 0.02), but there was no significant difference for the high dose vs. the moderate dose (p > 0.05). Participants consumed 34% fewer kilocalories after ingesting the lowest effective dose of methylphenidate compared with placebo (725.7 +/- 404.5 vs.1095 +/- 271.1 kcal, p < 0.01). Seven of nine subjects responded to the moderate dose. The increase in perceived drug effect above placebo was correlated with the reduction in energy intake for both the moderate (r = -0.85, p = 0.004) and the high (r = -0.75 p = 0.021) doses. Hunger scores were not different across drug doses or placebo before drug administration. DISCUSSION Methylphenidate reduced energy intake of a highly palatable food over one meal by one-third in obese adult males. Dopamine transport inhibition may be an effective component of a comprehensive treatment for obesity.
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Affiliation(s)
- John J Leddy
- Department of Orthopedics, Sports Medicine Institute, University at Buffalo School of Medicine and Biomedical Sciences, Buffalo, New York 14214, USA.
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Correll CU, Malhotra AK. Pharmacogenetics of antipsychotic-induced weight gain. Psychopharmacology (Berl) 2004; 174:477-89. [PMID: 15243737 DOI: 10.1007/s00213-004-1949-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2004] [Accepted: 05/28/2004] [Indexed: 02/08/2023]
Abstract
RATIONALE Antipsychotic medications have been associated with considerable weight gain. The degree of inter-individual variability and known genetic contributions to obesity suggest a combination of genetic and environmental factors. In the absence of established mechanisms and valid predictors for this relevant adverse effect, pharmacogenetic studies may provide the basis for the development of individualized treatment and preventive interventions. OBJECTIVE The aim of the present review is to analyze the theoretical and empirical knowledge base for the selection of the most promising target genes that may contribute to antipsychotic-induced weight gain. METHODS Examination of the preclinical and clinical literature that can inform the rational choice of target genes that may play a role in the development of adverse changes in body composition associated with antipsychotic treatment. RESULTS Theoretically, candidate gene selection can be guided by knowledge about molecular pathways associated with obesity, receptors modulated by antipsychotic drugs, and enzymes implicated in their metabolism and bioavailability. While most available data relate to the general mechanisms of obesity and few studies have directly examined the genetic contributions to antipsychotic-induced weight gain, several genes warrant further investigation. These include the 5-HT(2C), pro-opiomelanocortin, leptin, ghrelin, tumor necrosis factor alpha, adiponectin, dopamine D(2) receptor, histamine-H(1) receptor, and alpha(1), beta(2) and beta(3) adrenergic receptor genes. CONCLUSIONS Pharmacogenetic studies can provide powerful tools for the pre-treatment identification of individuals at high risk for antipsychotic-induced weight gain, to uncover biological mechanisms that may even generalize to non-drug-induced weight gain, and to isolate novel targets for treatments of weight gain and obesity. To enhance power, future studies should pay close attention to population selection and avoidance/control of confounds, particularly past treatment exposure.
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Affiliation(s)
- Christoph U Correll
- Department of Psychiatry Research, The Zucker Hillside Hospital, North Shore-Long Island Jewish Health System, Glen Oaks, NY 11004, USA
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Epstein LH, Wright SM, Paluch RA, Leddy JJ, Hawk LW, Jaroni JL, Saad FG, Crystal-Mansour S, Shields PG, Lerman C. Relation between food reinforcement and dopamine genotypes and its effect on food intake in smokers. Am J Clin Nutr 2004; 80:82-8. [PMID: 15213032 DOI: 10.1093/ajcn/80.1.82] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Food reinforcement and dopaminergic activity may influence food consumption, but research on whether they interact has not been performed. OBJECTIVE We assessed the effects of food reinforcement and the interaction of food reinforcement with the dopamine transporter (SLC6A3) genotype and the dopamine D(2) receptor (DRD(2)) genotype on energy consumption. DESIGN We studied food-consumption and reinforcing-value-of-food tasks in 88 smokers of European ancestry before they enrolled in smoking-cessation treatment. In the food-consumption task, subjects tasted and consumed 8 snack foods ad libitum. The reinforcing-value-of-food task assessed how hard subjects would work for food. RESULTS Significant interactions between dopamine genotypes and food reinforcement were observed. Subjects high in food reinforcement who lacked an SLC6A3*9 allele consumed significantly more calories (>150 kcal; P = 0.015) than did subjects low in food reinforcement or those high in food reinforcement who carried at least one SLC6A3*9 allele. Similarly, subjects high in food reinforcement who carried at least one DRD(2)*A1 allele consumed >130 kcal more (P = 0.021) than did subjects low in food reinforcement or those high in food reinforcement who lacked a DRD(2)*A1 allele. There was also a main effect of food reinforcement on energy intake (P = 0.005), with subjects high in food reinforcement consuming 104 kcal (or 30%) more than did subjects low in food reinforcement. CONCLUSIONS Food reinforcement has a significant effect on energy intake, and the effect is moderated by the dopamine loci SLC6A3 and DRD(2).
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Affiliation(s)
- Leonard H Epstein
- Departments of Pediatrics, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, 14214-3000, USA.
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Murphy DL, Uhl GR, Holmes A, Ren-Patterson R, Hall FS, Sora I, Detera-Wadleigh S, Lesch KP. Experimental gene interaction studies with SERT mutant mice as models for human polygenic and epistatic traits and disorders. GENES BRAIN AND BEHAVIOR 2004; 2:350-64. [PMID: 14653307 DOI: 10.1046/j.1601-1848.2003.00049.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Current evidence indicates that virtually all neuropsychiatric disorders, like many other common medical disorders, are genetically complex, with combined influences from multiple interacting genes, as well as from the environment. However, additive or epistatic gene interactions have proved quite difficult to detect and evaluate in human studies. Mouse phenotypes, including behaviors and drug responses, can provide relevant models for human disorders. Studies of gene-gene interactions in mice could thus help efforts to understand the molecular genetic bases of complex human disorders. The serotonin transporter (SERT, 5-HTT, SLC6A4) provides a relevant model for studying such interactions for several reasons: human variants in SERT have been associated with several neuropsychiatric and other medical disorders and quantitative traits; SERT blockers are effective treatments for a number of neuropsychiatric disorders; there is a good initial understanding of the phenotypic features of heterozygous and homozygous SERT knockout mice; and there is an expanding understanding of the interactions between variations in SERT expression and variations in the expression of a number of other genes of interest for neuropsychiatry and neuropharmacology. This paper provides examples of experimentally-obtained interactions between quantitative variations in SERT gene expression and variations in the expression of five other mouse genes: DAT, NET, MAOA, 5-HT(1B) and BDNF. In humans, all six of these genes possess polymorphisms that have been independently investigated as candidates for neuropsychiatric and other disorders in a total of > 500 reports. In the experimental studies in mice reviewed here, gene-gene interactions resulted in either synergistic, antagonistic (including 'rescue' or 'complementation') or more complex, quantitative alterations. These were identified in comparisons of the behavioral, physiological and neurochemical phenotypes of wildtype mice vs. mice with single allele or single gene targeted disruptions and mice with partial or complete disruptions of multiple genes. Several of the descriptive phenotypes could be best understood on the basis of intermediate, quantitative alterations such as brain serotonin differences. We discuss the ways in which these interactions could provide models for studies of gene-gene interactions in complex human neuropsychiatric and other disorders to which SERT may contribute, including developmental disorders, obesity, polysubstance abuse and others.
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Affiliation(s)
- D L Murphy
- Laboratory of Clinical Science, Building 10, Room 3D41, 10 Center Drive, NIMH, NIH/ DHHS, Bethesda, MD 20892-1264, USA.
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