Different levels of food restriction have opposite effects on adipocyte cellularity and lipoprotein-lipase activity in obese rats.
The effects of several levels of chronic energy restriction on epididymal and perirenal adipose tissue cellularity and lipoprotein lipase activity, serum glucose and insulin and hepatic enzyme activities were studied in lean Fa/- and genetically obese fafa rats. The restricted rats were compared to rats fed ad libitum 24/24h or 8/24h. Restricting time of feeding was associated with increases in fat cell number in the lean, increases in perirenal adipose tissue fat cell size and serum insulin in the obese and increases in lipoprotein lipase activity in both phenotypes. Mild food restriction (-25%) had similar effects in the obese: perirenal adipose tissue fat cell size and serum insulin levels were even higher but fat cell hyperplasia was reduced. Restriction by 50% normalized lipoprotein lipase activity and markedly reduced fat cell size in the lean; in the obese, lipoprotein lipase activity and insulin levels were similar to or lower than those of the corresponding ad libitum 24/24h group but fat cell hypertrophy was not particularly affected. Restriction by 75% in the obese prevented adipocyte hyperplasia. Furthermore, lipoprotein lipase activity in adipose tissue was normalized, serum insulin and lipids being within normal limits. However, these animals had large adipocytes and were still fat.
Lemonnier
D
D
U1 INSERM, Unité de Recherches sur la Nutrition et l'Alimentation, Hôpital Bichat, Paris.
de Gasquet
P
P
Mackay
S
S
Planche
E
E
Alexiu
A
A
Rosselin
G
G
Loiseau
A
A
D000273:Adipose Tissue / Q000201:enzymology / Q000473:pathology / Q000503:physiopathology*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D004038:Diet, Reducing; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008071:Lipoprotein Lipase / Q000378:metabolism*; D009765:Obesity / Q000201:enzymology / Q000503:physiopathology*; D010734:Phosphogluconate Dehydrogenase / Q000378:metabolism; D051381:Rats; D011924:Rats, Zucker
D001786:Blood Glucose; D007328:Insulin; D008055:Lipids; D010734:Phosphogluconate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D008071:Lipoprotein Lipase