title: Effect of Early Overfeeding on Palatable Food Preference and Brain Dopaminergic Reward System at Adulthood: Role of Calcium Supplementation.
abstract: Rats raised in small litters (SL) are obese and hyperphagic. In the present study, we evaluated whether obesity is associated with changes in the mesocorticolimbic dopaminergic reward system in these animals at adulthood. We also assessed the anti-obesity effects of dietary calcium supplementation. To induce early overfeeding, litters were adjusted to three pups on postnatal day (PN)3 (SL group). Control litters were kept with 10 pups each until weaning (NL group). On PN120, SL animals were subdivided into two groups: SL (standard diet) and SL-Ca [SL with calcium supplementation (10 g calcium carbonate/kg rat chow) for 60 days]. On PN175, animals were subjected to a food challenge: animals could choose between a high-fat (HFD) or a high-sugar diet (HSD). Food intake was recorded after 30 min and 12 h. Euthanasia occurred on PN180. SL rats had higher food intake, body mass and central adiposity. Sixty days of dietary calcium supplementation (SL-Ca) prevented these changes. Only SL animals preferred the HFD at 12 h. Both SL groups had lower tyrosine hydroxylase content in the ventral tegmental area, lower dopaminergic transporter content in the nucleus accumbens, and higher type 2 dopamine receptor (D2R) content in the hypothalamic arcuate nucleus (ARC). They also had higher neuropeptide Y (NPY) and lower pro-opiomelanocortin contents in the ARC. Calcium treatment normalised only D2R and NPY contents. Precocious obesity induces long-term effects in the brain dopaminergic system, which can be associated with an increased preference for fat at adulthood. Calcium treatment prevents this last alteration, partially through its actions on ARC D2R and NPY proteins.
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: E P S
authors.initials: EP
authors.lastname: Conceição
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: J C
authors.initials: JC
authors.lastname: Carvalho
authors.affiliation: Laboratory of Neurophysiology, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Manhães
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: D S
authors.initials: DS
authors.lastname: Guarda
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: M S
authors.initials: MS
authors.lastname: Figueiredo
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: F T
authors.initials: FT
authors.lastname: Quitete
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Oliveira
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: E G
authors.initials: EG
authors.lastname: Moura
authors.affiliation: Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: P C
authors.initials: PC
authors.lastname: Lisboa
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002136:Calcium, Dietary / Q000008:administration & dosage*; D059305:Diet, High-Fat; D004298:Dopamine / Q000378:metabolism*; D004435:Eating; D002149:Energy Intake; D005260:Female; D005518:Food Preferences; D008297:Male; D009478:Neuropeptide Y / Q000378:metabolism; D009714:Nucleus Accumbens / Q000378:metabolism; D009765:Obesity / Q000378:metabolism* / Q000523:psychology*; D011333:Pro-Opiomelanocortin / Q000378:metabolism; D017208:Rats, Wistar; D017448:Receptors, Dopamine D2 / Q000378:metabolism; D012201:Reward; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D017557:Ventral Tegmental Area / Q000378:metabolism
chemical_list: D002136:Calcium, Dietary; D009478:Neuropeptide Y; D017448:Receptors, Dopamine D2; D011333:Pro-Opiomelanocortin; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine
keywords: food preference; mesocorticolimbic system; obesity; small litter