Full text is available at the source.
Feeding Cues Alter Clock Gene Oscillations and Photic Responses in the Suprachiasmatic Nuclei of Mice Exposed to a Light/Dark Cycle
Feeding signals change daily gene rhythms and light responses in the brain’s internal clock of mice in light/dark cycles
AI simplified
Abstract
Hypocaloric feeding at midday led to 2-4 hour phase advances in locomotor activity rhythm and other circadian outputs in mice.
- Normocaloric feeding resulted in predominantly diurnal food intake (60%) and decreased afternoon blood glucose but did not alter the phase of locomotor activity or vasopressin expression in the suprachiasmatic nuclei (SCN).
- In contrast, hypocaloric feeding decreased daily blood glucose and caused significant phase advances in locomotor activity rhythm, pineal melatonin, and vasopressin mRNA cycles in the SCN.
- Oscillations of the genes Per1 and Cry2 in the SCN were advanced by 1 and 3 hours, respectively, only in mice subjected to hypocaloric feeding.
- The expression phases of the genes Per2 and Bmal1 remained unchanged regardless of the feeding condition.
- The behavioral phase-response curve to light, as well as light-induced expression of Per1 in the SCN, were significantly altered in hypocaloric-fed mice compared to those fed ad libitum.
- These findings suggest that energy metabolism may influence circadian rhythmicity and the processing of light signals in mammals.
AI simplified