Behavioral deficits during early stages of aging in Caenorhabditis elegans result from locomotory deficits possibly linked to muscle frailty.
Many behavioral responses require the coordination of sensory inputs with motor outputs. Aging is associated with progressive declines in both motor function and muscle structure. However, the consequences of age-related motor deficits on behavior have not been clearly defined. Here, we examined the effects of aging on behavior in the nematode, Caenorhabditis elegans. As animals aged, mild locomotory deficits appeared that were sufficient to impair behavioral responses to sensory cues. In contrast, sensory ability appeared well maintained during aging. Age-related behavioral declines were delayed in animals with mutations in the daf-2/insulin-like pathway governing longevity. A decline in muscle tissue integrity was correlated with the onset of age-related behavioral deficits, although significant muscle deterioration was not. Treatment with a muscarinic agonist significantly improved locomotory behavior in aged animals, indicating that improved neuromuscular signaling may be one strategy for reducing the severity of age-related behavioral impairments.
Glenn
Charles F
CF
Laboratory of Neuosciences, National Institue on Aging, Baltimore, MD 21224, USA.
Chow
David K
DK
David
Lawrence
L
Cooke
Carol A
CA
Gami
Minaxi S
MS
Iser
Wendy B
WB
Hanselman
Keaton B
KB
Goldberg
Ilya G
IG
Wolkow
Catherine A
CA
D000109:Acetylcholine / Q000378:metabolism; D000375:Aging / Q000502:physiology / Q000523:psychology*; D000818:Animals; D017173:Caenorhabditis elegans / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D008124:Locomotion; D009046:Motor Neurons / Q000502:physiology; D018721:Muscarinic Agonists / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D009132:Muscles / Q000473:pathology / Q000502:physiology*; D009154:Mutation; D018722:Nicotinic Agonists / Q000494:pharmacology; D011972:Receptor, Insulin / Q000235:genetics; D012677:Sensation
D029742:Caenorhabditis elegans Proteins; D018721:Muscarinic Agonists; D018722:Nicotinic Agonists; C107483:DAF-2 protein, C elegans; D011972:Receptor, Insulin; D000109:Acetylcholine