title: Western High-Fat Diet Consumption during Adolescence Increases Susceptibility to Traumatic Stress while Selectively Disrupting Hippocampal and Ventricular Volumes.
abstract: Psychological trauma and obesity co-occur frequently and have been identified as major risk factors for psychiatric disorders. Surprisingly, preclinical studies examining how obesity disrupts the ability of the brain to cope with psychological trauma are lacking. The objective of this study was to determine whether an obesogenic Western-like high-fat diet (WD) predisposes rats to post-traumatic stress responsivity. Adolescent Lewis rats (postnatal day 28) were fedad libitumfor 8 weeks with either the experimental WD diet (41.4% kcal from fat) or the control diet (16.5% kcal from fat). We modeled psychological trauma by exposing young adult rats to a cat odor threat. The elevated plus maze and the open field test revealed increased psychological trauma-induced anxiety-like behaviors in the rats that consumed the WD when compared with control animals 1 week after undergoing traumatic stress (p< 0.05). Magnetic resonance imaging showed significant hippocampal atrophy (20% reduction) and lateral ventricular enlargement (50% increase) in the animals fed the WD when compared with controls. These volumetric abnormalities were associated with behavioral indices of anxiety, increased leptin and FK506-binding protein 51 (FKBP51) levels, and reduced hippocampal blood vessel density. We found asymmetric structural vulnerabilities to the WD, particularly the ventral and left hippocampus and lateral ventricle. This study highlights how WD consumption during adolescence impacts key substrates implicated in post-traumatic stress disorder. Understanding how consumption of a WD affects the developmental trajectories of the stress neurocircuitry is critical, as stress susceptibility imposes a marked vulnerability to neuropsychiatric disorders.
authors.affiliation: Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine , Loma Linda, California 92350.
authors.forename: Priya
authors.initials: P
authors.lastname: Kalyan-Masih
authors.affiliation: Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California 92350; Physiology Division, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California 92350.
authors.forename: Julio David
authors.initials: JD
authors.lastname: Vega-Torres
authors.affiliation: Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine , Loma Linda, California 92350.
authors.forename: Christina
authors.identifier: 0000-0003-3785-6585
authors.initials: C
authors.lastname: Miles
authors.affiliation: Department of Pediatrics, Loma Linda University School of Medicine , Loma Linda, California 92350.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Haddad
authors.affiliation: Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine , Loma Linda, California 92350.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Rainsbury
authors.affiliation: Department of Pediatrics, Loma Linda University School of Medicine , Loma Linda, California 92350.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Baghchechi
authors.affiliation: Department of Pediatrics, Loma Linda University School of Medicine , Loma Linda, California 92350.
authors.forename: Andre
authors.identifier: 0000-0001-6937-9563
authors.initials: A
authors.lastname: Obenaus
authors.affiliation: Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California 92350; Physiology Division, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California 92350.
authors.forename: Johnny D
authors.identifier: 0000-0003-4769-8736
authors.initials: JD
authors.lastname: Figueroa
mesh_terms: D000818:Animals; D001007:Anxiety / Q000000981:diagnostic imaging / Q000473:pathology; D002552:Cerebral Ventricles / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000473:pathology*; D066273:Diet, Western / Q000009:adverse effects*; D004198:Disease Susceptibility / Q000000981:diagnostic imaging / Q000473:pathology; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000473:pathology*; D020738:Leptin / Q000378:metabolism; D008297:Male; D008568:Memory; D009765:Obesity / Q000000981:diagnostic imaging / Q000209:etiology / Q000523:psychology; D009929:Organ Size; D011897:Random Allocation; D011917:Rats, Inbred Lew; D013216:Reflex, Startle; D013313:Stress Disorders, Post-Traumatic / Q000000981:diagnostic imaging / Q000473:pathology*; D013315:Stress, Psychological / Q000000981:diagnostic imaging / Q000473:pathology
chemical_list: D020738:Leptin
keywords: PTSD ; behavior; high-fat diet; hippocampus; imaging; obesity