title: Obesity diminishes synaptic markers, alters microglial morphology, and impairs cognitive function.
abstract: Obesity is a major public health problem affecting overall physical and emotional well-being. Despite compelling data suggesting an association between obesity and cognitive dysfunction, this phenomenon has received relatively little attention. Neuroimaging studies in obese humans report reduced size of brain regions involved in cognition, but few studies have investigated the cellular processes underlying cognitive decline in obesity or the influence of obesity on cognition in the absence of obesity-related illnesses. Here, a rat model of diet-induced obesity was used to explore changes in brain regions important for cognition. Obese rats showed deficits on cognitive tasks requiring the prefrontal and perirhinal cortex. Cognitive deficits were accompanied by decreased dendritic spine density and synaptic marker expression in both brain regions. Microglial morphology was also changed in the prefrontal cortex. Detrimental changes in the prefrontal cortex and perirhinal cortex occurred before metabolic syndrome or diabetes, suggesting that these brain regions may be particularly vulnerable to early stage obesity.
authors.affiliation: Department of Psychology, Princeton University, Princeton, NJ 08544; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544;
authors.forename: Miriam E
authors.initials: ME
authors.lastname: Bocarsly
authors.affiliation: Department of Psychology, Princeton University, Princeton, NJ 08544; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544;
authors.forename: Maria
authors.initials: M
authors.lastname: Fasolino
authors.affiliation: Department of Psychology, Princeton University, Princeton, NJ 08544; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544;
authors.forename: Gary A
authors.initials: GA
authors.lastname: Kane
authors.affiliation: Department of Psychology, Princeton University, Princeton, NJ 08544; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544;
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: LaMarca
authors.affiliation: Department of Psychology, Princeton University, Princeton, NJ 08544; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544;
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Kirschen
authors.affiliation: Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA 99164; Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY 10021.
authors.forename: Ilia N
authors.initials: IN
authors.lastname: Karatsoreos
authors.affiliation: Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY 10021 mcewen@mail.rockefeller.edu goulde@princeton.edu.
authors.forename: Bruce S
authors.initials: BS
authors.lastname: McEwen
authors.affiliation: Department of Psychology, Princeton University, Princeton, NJ 08544; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544; mcewen@mail.rockefeller.edu goulde@princeton.edu.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Gould
mesh_terms: D000818:Animals; D001007:Anxiety / Q000209:etiology; D048430:Cell Shape; D003072:Cognition Disorders / Q000209:etiology*; D003712:Dendrites / Q000473:pathology; D004195:Disease Models, Animal; D008297:Male; D017628:Microglia / Q000473:pathology*; D009765:Obesity / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013569:Synapses / Q000737:chemistry / Q000502:physiology*
keywords: cognition; dendritic spine; microglia; obesity; prefrontal cortex