Lesions of glucose-responsive neurons impair synchronizing effects of calorie restriction in mice.
Calorie restriction can induce phase-advances of daily rhythms in rodents exposed to light-dark cycles. To test whether glucose-responsive neurons are involved in the synchronizing effects of calorie restriction, C57BL/6J mice were injected with gold-thioglucose (GTG; 0.6 g/kg) which damages glucose-responsive neurons, primarily located in the ventromedial hypothalamus. From the day of injection, GTG-treated and control mice received a hypocaloric diet (66% of ad libitum food intake) 2 h after lights on. When mice were transferred to constant darkness after 4 weeks and fed ad libitum, the onset of circadian rhythm of locomotor activity was phase-advanced by 1 h in control but not in GTG-treated mice. Therefore, glucose-responsive neurons in the ventromedial hypothalamus may play a role in the synchronizing effects of calorie restriction on circadian rhythmicity.
Challet
E
E
Center for Circadian Biology and Medicine, Department of Neurobiology and Physiology, Northwestern University, 2153 North Campus Drive, Evanston, IL 60208, USA. e-challet@nwu.edu
Bernard
D J
DJ
Turek
F W
FW
D000818:Animals; D006051:Aurothioglucose / Q000008:administration & dosage / Q000494:pharmacology; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology; D002149:Energy Intake / Q000502:physiology*; D005508:Food Deprivation; D005947:Glucose / Q000502:physiology*; D007274:Injections, Intraperitoneal; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000187:drug effects; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology*; D017440:Photoperiod; D014697:Ventromedial Hypothalamic Nucleus / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D014851:Wakefulness / Q000187:drug effects
D006051:Aurothioglucose; D005947:Glucose