title: Extended exposure to sugar and/or caffeine produces distinct behavioral and neurochemical profiles in the orbitofrontal cortex of rats: Implications for neural function.
abstract: Caffeine is a psychostimulant commonly consumed with high levels of sugar. The increased availability of highly caffeinated, high sugar energy drinks could put some consumers at risk of being exposed to high doses of caffeine and sugar. Notably, research that has examined the consequences of this combination is limited. Here, we explored the effect of chronic exposure to caffeine and/or sugar on behavior and protein levels in the orbitofrontal cortex (OFC) of rats. The OFC brain region has been implicated in neuropsychiatric conditions, including obesity and addiction behaviors. Adult male Sprague-Dawley rats were treated for 26 days with control, caffeine (0.6 g/L), 10% sugar, or combination of both. Locomotor behavior was measured on the first and last day of treatment, then 1 week after treatment. Two hours following final behavioral testing, brains were rapidly removed and prepared for proteomic analysis of the OFC. Label-free quantitative shotgun analysis revealed that 21, 12, and 23% of proteins identified in the OFC were differentially expressed by sugar and/or caffeine. The results demonstrate that the intake of high levels of sugar and/or low to moderate levels of caffeine has different behavioral consequences. Moreover, each treatment results in a unique proteomic profile with different implications for neural health.
authors: Department of Psychology, Macquarie University, Sydney, NSW, Australia.
authors: Jane L
authors: JL
authors: Franklin
authors: Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia.
authors: Mehdi
authors: M
authors: Mirzaei
authors: Department of Psychology, Macquarie University, Sydney, NSW, Australia.
authors: Travis A
authors: TA
authors: Wearne
authors: Faculty of Human Sciences, Macquarie University, Sydney, NSW, Australia.
authors: Judi
authors: J
authors: Homewood
authors: Department of Biomedical Sciences, Macquarie University, Sydney, NSW, Australia.
authors: Ann K
authors: AK
authors: Goodchild
authors: Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia.
authors: Paul A
authors: PA
authors: Haynes
authors: Department of Psychology, Macquarie University, Sydney, NSW, Australia.
authors: Jennifer L
authors: JL
authors: Cornish
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001628:Beverages / Q000009:adverse effects; D002110:Caffeine / Q000009:adverse effects / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000009:adverse effects / Q000494:pharmacology*; D004040:Dietary Carbohydrates / Q000009:adverse effects / Q000494:pharmacology*; D008124:Locomotion / Q000187:drug effects; D008297:Male; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000502:physiology; D020543:Proteome / Q000032:analysis / Q000378:metabolism*; D040901:Proteomics; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects; D015430:Weight Gain / Q000187:drug effects
chemical_list: D000697:Central Nervous System Stimulants; D004040:Dietary Carbohydrates; D020543:Proteome; D002110:Caffeine
keywords: Animal proteomics; Caffeine; Hyperactivity; Neurological disease; Orbitofrontal cortex; Sugar