Age-related decline in motor behavior and striatal dopamine transporter in cynomolgus monkeys.
Advanced human aging is associated with progressive declines of motor function and a risk factor for Parkinson's disease, which mainly involves central nigrostriatal dopaminergic system. The present study investigated age-related changes in motor behaviors and alterations of the number of nigrostriatal dopaminergic terminals in non-human primates. A total of 30 cynomolgus monkeys (Macaca fascicularis) of age 3.5-15.5 years were studied. Motor behaviors including upper limb movement time and the amount of overall home cage activity were quantitatively assessed using a modified movement assessment panel and a newly developed webcam-based monitoring system. The function of the dopaminergic system was semi-quantitatively measured by (99m)Tc-TRODAT-1 uptake rates, a dopamine transporter (DAT) specific radiopharmaceutical with SPECT imaging. The results showed a significant decline in motor behaviors associated with aging which were significantly correlated with age-related decreases of (99m)Tc-TRODAT-1 uptake. A further partial correlation analysis independent of age indicated that age contributed to the relationship between striatal DAT levels and motor behaviors. Our results indicate that normal aging-related dopamine physiology influences certain aspects of motor behaviors and suggest that aging-associated dysfunction in the nigrostriatal dopaminergic system may be an important factor contributing to the decline of motor behaviors in aging cynomolgus monkeys.
Department of Neurobiology and Neurology, Beijing Institute of Geriatrics, Xuanwu Hospital of Capital University of Medical Sciences, 45 Changchun Street, Beijing, China.
Feng
F
Yue
Sien
S
Zeng
Di
D
Wu
Deqiao
D
Yi
Y
Y
Alex Zhang
Piu
P
Chan
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D008252:Macaca fascicularis; D009043:Motor Activity / Q000502:physiology*; D015899:Tomography, Emission-Computed, Single-Photon
D050483:Dopamine Plasma Membrane Transport Proteins