Longevity & AgingCircadian Clocks Protect the Liver From Fat Buildup During Calorie Restriction
Calorie restriction (CR) and unanticipated fasting (F) both raise blood ketones and free fatty acids, yet only fasting triggers fat accumulation in the liver. Researchers at Cleveland State University found that CR prevents this hepatic steatosis not through stronger fat-burning, but by suppressing genes that transport fatty acids into liver cells, synthesize triglycerides, and form lipid droplets. The circadian clock and the animal's learned anticipation of its daily meal were both required for this protection. When clock genes were knocked out or the expected meal was skipped, CR mice developed liver fat accumulation similar to fasted mice — identifying a circadian-gating mechanism as a critical guardian of liver lipid homeostasis.
