title: Feeding during the resting phase causes profound changes in physiology and desynchronization between liver and muscle rhythms of rats.
abstract: Shiftworkers run an increased risk of developing metabolic disorders, presumably as a result of disturbed circadian physiology. Eating at a time-of-day that is normally dedicated to resting and fasting, may contribute to this association. The hypothalamus is the key brain area that integrates different inputs, including environmental time information from the central biological clock in the suprachiasmatic nuclei, with peripheral information on energy status to maintain energy homeostasis. The orexin system within the lateral hypothalamus is an important output of the suprachiasmatic nuclei involved in the control of sleep/wake behavior and glucose homeostasis, among other functions. In this study, we tested the hypothesis that feeding during the rest period disturbs the orexin system as a possible underlying contributor to metabolic health problems. Male Wistar rats were exposed to an 8-week protocol in which food was available ad libitum for 24-h, for 12-h during the light phase (i.e., unnatural feeding time) or for 12-h during the dark phase (i.e., restricted feeding, but at the natural time-of-day). Animals forced to eat at an unnatural time, i.e., during the light period, showed no changes in orexin and orexin-receptor gene expression in the hypothalamus, but the rhythmic expression of clock genes in the lateral hypothalamus was absent in these animals. Light fed animals did show adverse changes in whole-body physiology and internal desynchronization of muscle and liver clock and metabolic gene expression. Eating at the 'wrong' time-of-day thus causes internal desynchronization at different levels, which in the long run may disrupt body physiology.
authors: Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.
authors: Anne-Loes
authors: AL
authors: Opperhuizen
authors: Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.|Institute of Plant Protection (IPP), Chinese Academy of Agricultural Science (CAAS), Beijing, China.
authors: Dawei
authors: D
authors: Wang
authors: Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands.
authors: Ewout
authors: E
authors: Foppen
authors: Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.
authors: Remi
authors: R
authors: Jansen
authors: Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands.
authors: Olga
authors: O
authors: Boudzovitch-Surovtseva
authors: Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.
authors: Janneke
authors: J
authors: de Vries
authors: Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands.
authors: Eric
authors: E
authors: Fliers
authors: Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.|Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands.
authors: Andries
authors: A
authors: Kalsbeek
mesh_terms: D000204:Activity Cycles; D000818:Animals; D056926:CLOCK Proteins / Q000235:genetics / Q000378:metabolism; D002940:Circadian Rhythm; D005247:Feeding Behavior; D007031:Hypothalamus / Q000378:metabolism / Q000502:physiology; D008099:Liver / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D064446:Orexin Receptors / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D064446:Orexin Receptors; D056926:CLOCK Proteins
keywords: circadian; energy metabolism; obesity; orexin; shiftwork