title: When chocolate seeking becomes compulsion: gene-environment interplay.
abstract: BACKGROUND
  Eating disorders appear to be caused by a complex interaction between environmental and genetic factors, and compulsive eating in response to adverse circumstances characterizes many eating disorders.
  
  
  METHODS
  We compared compulsion-like eating in the form of conditioned suppression of palatable food-seeking in adverse situations in stressed C57BL/6J and DBA/2J mice, two well-characterized inbred strains, to determine the influence of gene-environment interplay on this behavioral phenotype. Moreover, we tested the hypothesis that low accumbal D2 receptor (R) availability is a genetic risk factor of food compulsion-like behavior and that environmental conditions that induce compulsive eating alter D2R expression in the striatum. To this end, we measured D1R and D2R expression in the striatum and D1R, D2R and α1R levels in the medial prefrontal cortex, respectively, by western blot.
  
  
  RESULTS
  Exposure to environmental conditions induces compulsion-like eating behavior, depending on genetic background. This behavioral pattern is linked to decreased availability of accumbal D2R. Moreover, exposure to certain environmental conditions upregulates D2R and downregulates α1R in the striatum and medial prefrontal cortex, respectively, of compulsive animals. These findings confirm the function of gene-environment interplay in the manifestation of compulsive eating and support the hypothesis that low accumbal D2R availability is a "constitutive" genetic risk factor for compulsion-like eating behavior. Finally, D2R upregulation and α1R downregulation in the striatum and medial prefrontal cortex, respectively, are potential neuroadaptive responses that parallel the shift from motivated to compulsive eating.
authors.affiliation: Department of Applied Clinical Science and Biotechnology, University of L'Aquila, Coppito, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Patrono
authors.affiliation: Santa Lucia Foundation, Rome, Italy; Department of Psychology and Center "Daniel Bovet," Sapienza University, Rome, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Di Segni
authors.affiliation: Department of Applied Clinical Science and Biotechnology, University of L'Aquila, Coppito, Italy.
authors.forename: Loris
authors.initials: L
authors.lastname: Patella
authors.affiliation: Santa Lucia Foundation, Rome, Italy; Department of Applied Clinical Science and Biotechnology, University of L'Aquila, Coppito, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Andolina
authors.affiliation: Santa Lucia Foundation, Rome, Italy; Department of Psychology and Center "Daniel Bovet," Sapienza University, Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Valzania
authors.affiliation: Santa Lucia Foundation, Rome, Italy; Department of Psychology and Center "Daniel Bovet," Sapienza University, Rome, Italy.
authors.forename: Emanuele Claudio
authors.initials: EC
authors.lastname: Latagliata
authors.affiliation: CNR, Institute of Cellular Biology and Neurobiology, Rome, Italy.
authors.forename: Armando
authors.initials: A
authors.lastname: Felsani
authors.affiliation: Department of Applied Clinical Science and Biotechnology, University of L'Aquila, Coppito, Italy.
authors.forename: Assunta
authors.initials: A
authors.lastname: Pompili
authors.affiliation: Department of Applied Clinical Science and Biotechnology, University of L'Aquila, Coppito, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Gasbarri
authors.affiliation: Santa Lucia Foundation, Rome, Italy; Department of Psychology and Center "Daniel Bovet," Sapienza University, Rome, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Puglisi-Allegra
authors.affiliation: Santa Lucia Foundation, Rome, Italy; Department of Psychology and Center "Daniel Bovet," Sapienza University, Rome, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Ventura
mesh_terms: D000818:Animals; D056912:Binge-Eating Disorder / Q000235:genetics / Q000378:metabolism*; D002099:Cacao / Q000009:adverse effects*; D002182:Candy / Q000009:adverse effects*; D003192:Compulsive Behavior / Q000235:genetics / Q000378:metabolism*; D066249:Craving; D059647:Gene-Environment Interaction; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009714:Nucleus Accumbens / Q000378:metabolism; D017397:Prefrontal Cortex / Q000378:metabolism; D017447:Receptors, Dopamine D1 / Q000235:genetics / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000235:genetics / Q000378:metabolism; D013378:Substantia Nigra / Q000378:metabolism
chemical_list: D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2