IEPA.d109.s256
Fasting and leptin modulate adipose and muscle uncoupling protein: divergent effects between messenger ribonucleic acid and protein expression
IEPA.d109.s257
In this study, we examined the effects of fasting for 2 days and exogenous s.c. leptin, 200 microg every 8 h for 2 days, on the regulation of uncoupling protein (UCP) subtypes in brown adipose tissue (BAT) and gastrocnemius muscle
IEPA.d109.s258
Leptin, compared with vehicle, did not alter BAT UCP-1 or UCP-3 mRNA or protein expression when administered to normal ad libitum fed rats
IEPA.d109.s259
Fasting significantly decreased BAT UCP-1 and UCP-3 mRNA expression, to 31% and 30% of ad libitum fed controls, respectively, effects which were prevented by administration of leptin to fasted rats
IEPA.d109.s260
Fasting also significantly decreased BAT UCP-1 protein expression, to 67% of control; however, that effect was not prevented by leptin treatment
IEPA.d109.s261
Fasting, with or without leptin administration, did not affect BAT UCP-2 mRNA; however, leptin administration to ad libitum fed rats significantly increased BAT UCP-2 mRNA, to 138% of control
IEPA.d109.s262
Fasting significantly enhanced gastrocnemius muscle UCP-3 mRNA (411% of control) and protein expression (168% of control), whereas leptin administration to fasted rats did not alter either of these effects
IEPA.d109.s263
In summary, UCP subtype mRNA and protein are regulated in tissue- and subtype-specific fashion by leptin and food restriction