Synergistic Effect of Feeding Time and Diet on Hepatic Steatosis and Gene Expression in Male Wistar Rats

Abstract

Objective Eating out of phase with the endogenous biological clock alters clock and metabolic gene expression in rodents and can induce obesity and type 2 diabetes mellitus. Diet composition can also affect clock gene expression. This study assessed the combined effect of diet composition and feeding time on (1) body composition, (2) energy balance, and (3) circadian expression of hepatic clock and metabolic genes. Methods Male Wistar rats were fed a chow or a free‐choice high‐fat, high‐sugar (fcHFHS) diet, either ad libitum or with food access restricted to either the light or dark period. Body weight, adiposity, and hepatic fat accumulation as well as hepatic clock and metabolic mRNA expression were measured after 5 weeks of the diet. Energy expenditure was measured using calorimetric cages. Results Animals with access to the fcHFHS diet only during the light period showed more hepatic fat accumulation than fcHFHS dark‐fed animals despite less calories consumed. In contrast, within the chow‐fed groups, light‐fed animals showed the lowest hepatic fat content, but they also showed the lowest caloric intake. Locomotor activity and heat production followed feeding times, except in the fcHFHS light‐fed group. Hepatic clock and metabolic gene expression rhythms also followed timing of food intake. Yet, in the fcHFHS light‐fed animals, clock gene expression appeared 3 hours advanced compared with chow light‐fed animals, an effect not observed in the fcHFHS dark‐fed animals. Conclusions An fcHFHS diet consumed in the light period promotes hepatic fat accumulation and advances clock gene expression in male Wistar rats, likely because of a mismatch between energy intake and expenditure.

Time‐restricted feeding during the inactive phase abolishes the daily rhythm in mitochondrial respiration in rat skeletal muscle

“…Thus, contrary to most mice studies, rats eating at the wrong time of day did not show an increased body weight, this could be due to the fact that in the current experiment the feeding period was only 10 h, instead of 12 h, or a stronger light‐induced inhibition of activity and feeding behavior during the light period in rats as compared to mice. In contrast, feeding efficiency was increased in the light‐fed animals and in previous experiments, we found increased adiposity in the light‐fed animals 37‐39 …”

“…In contrast, feeding efficiency was increased in the light-fed animals and in previous experiments, we found increased adiposity in the light-fed animals. [37][38][39] A subset of animals was housed in metabolic cages, first under AL (baseline) feeding conditions and subsequently under TRF conditions (4 weeks) to assess physical activity and substrate metabolism. As expected, light-fed and dark-fed animals did not eat during the dark and light phases, respectively (Figure 1E).…”

Identification of an endocannabinoid gut-brain vagal mechanism controlling food reward and energy homeostasis

“…Access to calories-rich food and time-restricted feeding are invariably associated with changes in circulating signals reflecting metabolic and behavioral adaptations [25]. In line with this, we observed that our BE model was associated with reduced circulating triglycerides and insulin, and increased circulating corticosterone during the anticipatory phase (Suppl.…”

Identification of an endocannabinoid gut-brain vagal mechanism controlling food reward and energy homeostasis

“…Access to calories-rich food and time-restricted feeding are invariably associated with changes in circulating signals reflecting metabolic and behavioral adaptations (Oosterman et al, 2020). In line with this, we observed that our model of BE was associated with reduced circulating triglycerides (TG) and insulin and concomitant increase in circulating corticosterone during the anticipatory phase (Figure 2A-C) while overall insulin sensitivity, as assessed by oral glucose tolerance test, remained unchanged (Figure 2D, E).…”