Daily anticipatory rhythms of behavior and body temperature in response to glucose availability in rats.

Abstract

When food is available recurrently at a particular time of day, several species increase their locomotion in the hours that precede food delivery, a phenomenon called food anticipatory activity (FAA). In mammals, many studies have shown that FAA is driven by a food-entrained circadian oscillator (FEO) that is distinct from the light-entrained pacemaker in the suprachiasmatic nucleus of the hypothalamus. Few studies have investigated the effect of sugar ingestion on food anticipatory rhythms and the FEO. We aimed to extend the understanding of the role of glucose on the emergence of food anticipatory rhythms by investigating whether glucose ingestion is sufficient to produce daily food anticipation, reflected by motor activity and core body temperature rhythms. Under a 12 h/12 h light/dark cycle, chow-deprived rats had glucose solution available between Zeitgeber Time (ZT) 6 and ZT 9 for 10 days (glucose restriction group), whereas control animals had chow available within the same time window (chow restriction group). Animals in both groups exhibited anticipatory motor activity and body temperature around the fourth day of the scheduled food restriction. Glucose-fed rats ingested ~15 kcal on the days immediately before FAA emergence and reached an intake of ~20 kcal/day, whereas chow-fed rats ingested ~40 kcal/day. The glucose restriction group exhibited a pattern of food anticipation (activity and temperature) that was extremely similar to that observed in the chow restriction group. We conclude that glucose ingestion is a sufficient temporal cue to produce recurrent food anticipation, reflected by activity and temperature rhythms, in rats.

A nonparametric methodological analysis of rest-activity rhythm in type 2 diabetes

“…Also, feeding time can entrain the intrinsic oscillation of clocks in liver cells, similar to what occurs in central oscillators in the brain when entrained by light 15 . These previous findings support the understanding that circadian and metabolic systems are reciprocally regulated 14 , 16 - 18 .…”

The effects of graded levels of calorie restriction: V. Impact of short term calorie and protein restriction on physical activity in the C57BL/6 mouse

“…Their earlier work had shown mice developed nutrient-dependent FAA to sweetened meal [ 93 ], however, chronically protein deprived mice did not show anticipation for a single protein meal (this was also true for carbohydrate and fat). More recent research, however, has concluded glucose availability can produce FAA in rats [ 94 ]. Results here show FAA was due to restriction of calories alone with no evidence that equivalent levels of PR increased FAA.…”

Inexpensive Home Infrared Living/Environment Sensor with Regional Thermal Information for Infant Physical and Psychological Development

“…The former pathway passed circuits via different B-mechanisms and then reached St4 ( Figure 13 B). The circadian positive and negative correlation shift emerged ( Figure 2 B) as contributing to the formation of more complex emotional mechanisms with a psychologically relevant BD [ 35 , 36 , 37 , 38 ] –BT [ 57 , 60 ] correlation. In contrast, the latter influenced the underlying basic mechanism because of the longitudinal effect in St2 but not St3, just after the dramatic change in home environment and when feeding times were reduced from three to two.…”