title: Beta-hydroxy-beta-methylbutyrate ameliorates aging effects in the dendritic tree of pyramidal neurons in the medial prefrontal cortex of both male and female rats.
abstract: Beta-hydroxy-beta-methylbutyrate (HMB), a supplement commonly used to maintain muscle in elderly and clinical populations, has been unexplored in the aging brain. In both healthy aging humans and rat models, there are cognitive deficits associated with age-related dendritic shrinkage within the prefrontal cortex. The present study explores the effects of relatively short- and long-term (7 and 31 weeks) oral HMB supplementation starting at 12 months of age in male and female rats on the dendritic tree of layer 5 pyramidal neurons in the medial prefrontal cortex. Since female rats continue to secrete ovarian hormones after reaching reproductive senescence, middle-aged female rats were ovariectomized to model humans. As expected, there were fewer spines and a retraction of dendritic material in the apical and basilar trees in old age controls of both sexes compared with their middle-aged counterparts. However, these losses did not occur in the HMB-treated rats in either dendrites or the total number of dendritic spines. Thus, HMB forestalled the effects of aging on the dendritic tree of this population of neurons.
authors.affiliation: Neuroscience Program, University of Illinois, Champaign, IL, USA.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Kougias
authors.affiliation: Department of Psychology, University of Illinois, Champaign, IL, USA.
authors.forename: Suzanne O
authors.initials: SO
authors.lastname: Nolan
authors.affiliation: Department of Psychology, University of Illinois, Champaign, IL, USA.
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Koss
authors.affiliation: Department of Psychology, University of Illinois, Champaign, IL, USA.
authors.forename: Taehyeon
authors.initials: T
authors.lastname: Kim
authors.affiliation: Department of Psychology, University of Illinois, Champaign, IL, USA.
authors.forename: Emily R
authors.initials: ER
authors.lastname: Hankosky
authors.affiliation: Neuroscience Program, University of Illinois, Champaign, IL, USA; Department of Psychology, University of Illinois, Champaign, IL, USA.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Gulley
authors.affiliation: Neuroscience Program, University of Illinois, Champaign, IL, USA; Department of Psychology, University of Illinois, Champaign, IL, USA. Electronic address: jjuraska@illinois.edu.
authors.forename: Janice M
authors.initials: JM
authors.lastname: Juraska
mesh_terms: D000284:Administration, Oral; D000375:Aging / Q000473:pathology*; D000818:Animals; D003712:Dendrites / Q000473:pathology*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D023421:Models, Animal; D010052:Ovariectomy; D017397:Prefrontal Cortex / Q000166:cytology* / Q000473:pathology*; D017966:Pyramidal Cells / Q000473:pathology*; D020318:Rats, Long-Evans; D014631:Valerates / Q000008:administration & dosage* / Q000494:pharmacology*
chemical_list: D014631:Valerates; C004961:beta-hydroxyisovaleric acid
keywords: Dendrite; Dendritic spine; Golgi; Ovariectomy; Sex difference; mTOR