title: On-going electroencephalographic rhythms related to cortical arousal in wild-type mice: the effect of aging.
abstract: Resting state electroencephalographic (EEG) rhythms reflect the fluctuation of cortical arousal and vigilance in a typical clinical setting, namely the EEG recording for few minutes with eyes closed (i.e., passive condition) and eyes open (i.e., active condition). Can this procedure be back-translated to C57 (wild type) mice for aging studies? On-going EEG rhythms were recorded from a frontoparietal bipolar channel in 85 (19 females) C57 mice. Male mice were subdivided into 3 groups: 25 young (4.5-6 months), 18 middle-aged (12-15 months), and 23 old (20-24 months) mice to test the effect of aging. EEG power density was compared between short periods (about 5 minutes) of awake quiet behavior (passive) and dynamic exploration of the cage (active). Compared with the passive condition, the active condition induced decreased EEG power at 1-2 Hz and increased EEG power at 6-10 Hz in the group of 85 mice. Concerning the aging effects, the passive condition showed higher EEG power at 1-2 Hz in the old group than that in the others. Furthermore, the active condition exhibited a maximum EEG power at 6-8 Hz in the former group and 8-10 Hz in the latter. In the present conditions, delta and theta EEG rhythms reflected changes in cortical arousal and vigilance in freely behaving C57 mice across aging. These changes resemble the so-called slowing of resting state EEG rhythms observed in humans across physiological and pathological aging. The present EEG procedures may be used to enhance preclinical phases of drug discovery in mice for understanding the neurophysiological effects of new compounds against brain aging.
authors.affiliation: IRCCS SDN, Naples, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Del Percio
authors.affiliation: Janssen Research and Development, Pharmaceutical Companies of J&J, Beerse, Belgium.
authors.forename: Wilhelmus
authors.initials: W
authors.lastname: Drinkenburg
authors.affiliation: Department of Physiology and Pharmacology, University of Rome "Sapienza", Rome, Italy.
authors.forename: Susanna
authors.initials: S
authors.lastname: Lopez
authors.affiliation: IRCCS San Raffaele Pisana, Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Infarinato
authors.affiliation: H. Lundbeck A/S, Valby, Denmark.
authors.forename: Jesper Frank
authors.initials: JF
authors.lastname: Bastlund
authors.affiliation: H. Lundbeck A/S, Valby, Denmark.
authors.forename: Bettina
authors.initials: B
authors.lastname: Laursen
authors.affiliation: H. Lundbeck A/S, Valby, Denmark.
authors.forename: Jan T
authors.initials: JT
authors.lastname: Pedersen
authors.affiliation: H. Lundbeck A/S, Valby, Denmark.
authors.forename: Ditte Zerlang
authors.initials: DZ
authors.lastname: Christensen
authors.affiliation: Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milan, Italy.
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Forloni
authors.affiliation: Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milan, Italy.
authors.forename: Angelisa
authors.initials: A
authors.lastname: Frasca
authors.affiliation: Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milan, Italy.
authors.forename: Francesco M
authors.initials: FM
authors.lastname: Noè
authors.affiliation: Department of Neurological Science (DSNNMM), University of Verona, Verona, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Bentivoglio
authors.affiliation: Department of Neurological Science (DSNNMM), University of Verona, Verona, Italy.
authors.forename: Paolo Francesco
authors.initials: PF
authors.lastname: Fabene
authors.affiliation: Department of Neurological Science (DSNNMM), University of Verona, Verona, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Bertini
authors.affiliation: Department of Neurological Science (DSNNMM), University of Verona, Verona, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Colavito
authors.affiliation: Janssen Research and Development, Pharmaceutical Companies of J&J, Beerse, Belgium.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Kelley
authors.affiliation: Eli Lilly, Erl Wood Manor, Windlesham, Surrey, UK.
authors.forename: Sophie
authors.initials: S
authors.lastname: Dix
authors.affiliation: GlaxoSmithKline R&D Neurotherapeutics Area UK, Stevenage, Hertfordshire, UK.
authors.forename: Jill C
authors.initials: JC
authors.lastname: Richardson
authors.affiliation: Department of Physiology and Pharmacology, University of Rome "Sapienza", Rome, Italy; IRCCS San Raffaele Pisana, Rome, Italy. Electronic address: claudio.babiloni@uniroma1.it.
authors.forename: Claudio
authors.initials: C
authors.lastname: Babiloni
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001143:Arousal / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology*; D055808:Drug Discovery; D004569:Electroencephalography; D005260:Female; D008297:Male; D008810:Mice, Inbred C57BL; D012146:Rest / Q000502:physiology; D014851:Wakefulness / Q000502:physiology
keywords: Awake active state; Awake passive state; C57 wild-type (WT) mice; Electroencephalographic (EEG) rhythms