Metabolism gets clocked

The paper: F.W. Turek et al., "Obesity and metabolic syndrome in circadian Clock mutant mice." Science, 308:1043, 2005. (Cited in 90 papers) The finding: Joe Bass and others at Northwestern University found that mice with a mutated Clock gene showed both abnormal circadian rhythms and feeding behavior. Metabolic problems included obesity and abnormally high levels of blood cholesterol. The surprise: Circadian variatio

Manasee Wagh
Mar 31, 2007

The paper:

F.W. Turek et al., "Obesity and metabolic syndrome in circadian Clock mutant mice." Science, 308:1043, 2005. (Cited in 90 papers)

The finding:

Joe Bass and others at Northwestern University found that mice with a mutated Clock gene showed both abnormal circadian rhythms and feeding behavior. Metabolic problems included obesity and abnormally high levels of blood cholesterol.

The surprise:

Circadian variation in insulin secretion and action has long been recognized, says Bass, professor at Evanston Northwestern Healthcare. "What's changed is we now have a new molecular window on pathways that give rise to the observed circadian characteristics in the regulation of glucose homeostasis."

The verdict:

Colleen McClung, a circadian researcher at the University of Texas Southwestern Medical Center, Dallas, writes via E-mail that she was struck by "the broad range of metabolic phenotypes that are present in the Clock mutants ... It will be interesting to determine how...

The numbers:
Energy Intake (kcal/wk) Body weight (g)
Wild-type mice (regular diet) 84.1 29.5
Clock mice (regular diet) 91.8 33.8
Wild-type mice (high-fat diet) 92.4 32.1
Clock mice (high-fat diet) 105.4 40.3