A circadian oscillator regulates a food anticipatory increase in heart rate and body temperature

Autor: Abhilash Prabhat, Elizabeth Schroder, Isabel Stumpf, Rebecca Stalcup, Tanya Seward, Julie Pendergast, Brian Delisle
Rok vydání: 2023
Předmět:
Zdroj: Physiology. 38
ISSN: 1548-9221
1548-9213
DOI: 10.1152/physiol.2023.38.s1.5734457
Popis: Objective: The daily rhythm in heart rate is classically considered to be regulated by the circadian clock in the suprachiasmatic nucleus (SCN). The circadian clock in the SCN entrains to the light-dark cycle. However, some circadian rhythms can be entrained to meal timing independently of the SCN. In this study, we tested the hypothesis that heart rate is entrained by meal timing. Methodology: Wild-type male and female mice were implanted with telemetry devices to continually record HR and CBT in thermoneutral conditions. The mice were initially housed in a 12 h light: 12 h dark cycle (LD) with ad libitum access to food (ALF) for 7 days. Mice were then subjected to light cycle time-restricted feeding (TRF) between hours 2 and 9 (hour 0: lights on; hour 12: lights off) for 5 days, followed by 3 days in constant darkness (DD). The mice were then fed ALF for 3 days in DD to determine if food anticipatory rhythms persisted in constant conditions. Results: During ALF feeding in LD, HR and CBT increased at hours 11-13 and corresponded with the onset of nocturnal activity. In contrast, after 1 day of light cycle TRF, HR increased during the 2 hours prior to mealtime between hours 0-2. The food anticipatory increase in HR persisted during TRF in DD. The food-entrained anticipatory increase in HR and CBT remained phase-locked to prior mealtime when mice were returned to ALF after TRF. In contrast to the food-entrained anticipatory increase in HR and CBT, the circadian rhythms in HR and CBT dissociated and shifted back to the phase seen in ALF in LD. There were no sex differences. Conclusions: These data demonstrate that male and female mice have food-anticipatory increases in HR and CBT. Entrainment of the food anticipatory increase in HR and CBT to meal timing during TRF persisted in the absence of zeitgebers (in constant feeding and lighting conditions). Together these findings suggest that a food-entertainable oscillator regulates food-anticipatory increase HR and CBT rhythms independently of the SCN. Funding sources: The present work is supported by the National Heart Lung and Blood Institute grants R01HL153042 and R01HL141343. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Databáze: OpenAIRE
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