Time-dependent effects of a high-energy-yielding diet on the regulation of specific white adipose tissue genes

White adipose tissue development is regulated by many factors, including the energy content of food and the genetic background. Nevertheless, little is known about possible differential effects of high-fat palatable diets when fed for short or longtime periods. Thus, the expression of certain genes involved with lipid metabolism (peroxisome proliferator-activated receptor gamma, PPAR gamma2; retinoic receptors; fatty acid binding protein, aP2 and uncoupling proteins, UCP) may be affected by those dietary manipulations (high-energy-yielding diet and time duration of feeding). High-fat feeding for 8 days decreased mRNA UCP3 levels compared to control fed animals, while feeding for 30 days increased them over controls. Similar findings occurred for PPAR gamma2 and aP2. Furthermore, statistically significant associations were found among PPAR gamma2, aP2 and UCP3 mRNA levels. These data suggest a physiological time-dependent response seeking to prevent excessive fat deposition when animals are fed for short-term with a high amount of dietary fat, which was followed by an adaptive period to the high-energy content of diet throughout a coregulation among certain lipid metabolism related genes: PPAR gamma2, aP2, UCP3. (C) 2001 Academic Press.