Effect of feed restriction on adipose tissue transcript concentrations in genetically lean and obese pigs

To determine possible genetic influences on the steady-state concentrations of several key transcription factor transcripts and the transcript concent rations for adipocyte-characteristic proteins, young, genetically obese and lean pigs were given ad libitum access or feed or were restrictively fed a t 50% of ad libitum intake for 5 wk. Obese pigs were smaller and fatter tha n lean pigs, whether intake was ad Libitum or restrictive. Plasma protein, albumin, and cholesterol concentrations were greater in obese than in lean pigs. Plasma NEFA, blood urea nitrogen, triacylglycerols, and postprandial glucose and insulin concentrations were less (P < .02) in pigs fed restrict ively than in pigs with ad libitum access to feed, regardless of genetic gr oup. The adipose tissue glucose transporter 4, fatty acid synthase, and lep tin transcript concentrations were greater (P < .05) in obese than in lean pigs. The CCAAT/enhancer binding proteins beta and alpha, adipocyte fatty a cid binding protein, hormone-sensitive lipase, and the beta 1-adrenergic re ceptor transcript concentrations tended (P < .10) to be greater in adipose tissue from obese than in that from lean pigs. Several other transcripts we re numerically greater in obese than in lean pigs. The data collectively su ggest that messenger RNA concentration for several adipose tissue proteins is a contributing factor to the excess fat deposition in these obese pigs. Restricted feeding did not change the concentration of any transcript excep t that for adipocyte fatty acid binding protein, which was reduced. The acc retion of fat was markedly reduced in the restrictively fed pigs, but this diminution does not seem to be regulated by modulation of messenger RNA con centration.