title: Manipulation of serotonin signal suppresses early phase of behavioral aging in Caenorhabditis elegans.
abstract: Aging is associated with progressive changes in behavioral functions, in part caused by muscle frailty, called sarcopenia. However, it was not clear whether certain neurotransmitters are directly involved in behavioral aging. Here we investigated aging of locomotion behaviors with an associative learning property, called basal and enhanced slowing response in Caenorhabditis elegans. Basal slowing response is a modest slowdown in response to food, while enhanced slowing response is a greater slowdown response when animals experience starvation. The behaviors are mediated by dopamine and serotonin, respectively. During aging, basal slowing response was increased, resulting in a diminished difference between the two slowing responses. The behavioral change occurred during early phase of aging prior to the timing when sarcopenia was observed in previous studies. Interestingly, expression of a serotonin biosynthesis marker, tph-1Colon, two colonsGFP, was increased in old animals. Serotonin receptor antagonists and deletion mutants of their target receptor genes (ser-1 and ser-4) partially suppressed age-related changes in locomotion behaviors. Thus, manipulating serotonin signal at receptor levels suppresses early phase of locomotion aging.
authors.affiliation: Gheens Center on Aging, Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, 580 S Preston Street, BaxterII, RM102, Louisville, KY 40202, United States.
authors.forename: Hana
authors.initials: H
authors.lastname: Murakami
authors.forename: Karalee
authors.initials: K
authors.lastname: Bessinger
authors.forename: Jason
authors.initials: J
authors.lastname: Hellmann
authors.forename: Shin
authors.initials: S
authors.lastname: Murakami
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D017173:Caenorhabditis elegans / Q000502:physiology*; D005684:Gait / Q000502:physiology*; D007858:Learning / Q000502:physiology*; D012701:Serotonin / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D012701:Serotonin