Metabolic parameters are food-entrained in rats made cirrhotic by chronic CCl₄ treatment

Abstract

Food entrainment of clock genes in peripheral tissues and anticipatory response in the liver of rats maintained under a restricted feeding schedule have suggested that the liver may be a relevant element for a food entrained oscillator (FEO). Recent data suggest that mechanisms underlying food-entrainment for metabolic and behavioral or locomotor food anticipatory activity may depend on different regulatory systems. In a previous study we reported that a dysfunctional liver does not prevent animals from exhibiting behavioral anticipatory activity associated with restricted feeding schedules (RFS). The present study aimed to determine whether in CCl₄ cirrhotic rats metabolic parameters are entrained to RFS. Chronic CCl₄ treated cirrhotic rats and oil treated controls were entrained to RFS. After 2 weeks, rats were sacrificed 2 and 0 h before and 2 and 4 h after mealtime. Serum glucose and free fatty acids were determined as well as liver glycogen. Both groups exhibited a similar entrained pattern in the three parameters. Thus we conclude that anatomical and functional alterations produced by chronic administration of CCl₄ do not interfere with entrainment of metabolic parameters to RFS and point out the relevance of other mechanisms independent of the liver to drive peripheral food entrained rhythms.

Keywords:

• Circadian rhythms
• restricted feeding schedules
• liver
• free fatty acids
• glucose
• glycogen

Acknowledgements

This study was supported by grants CONACyT-México 33033-N and DGAPA-UNAM IN-204800 and IN-203803.