Effect of a moderate weight loss on adipose tissue lipoprotein lipase activity and expression: existence of sexual variation and regional differences.
OBJECTIVE
To evaluate the impact of moderate body weight loss on both adipose tissue lipoprotein lipase (AT-LPL) activity and expression and to verify whether variation in AT-LPL could be related to changes in lipid-lipoprotein metabolism.


METHODS
Intervention study of a 15-week weight reducing program (energy deficit: 500-800 kcal/d below the subjects' estimated sedentary energy expenditure).


METHODS
Thirty two obese subjects (14 men and 18 premenopausal women; aged 36-50 y) whose body fatness ranged from 34 to 54% fat.


METHODS
Adipose tissue biopsies from the abdominal and femoral depots, various fatness and fat distribution parameters (computed tomography and anthropometry), fasting plasma concentrations of high- and low-density lipoprotein cholesterol (HDL-C, LDL-C), and triglycerides at baseline and 4-6 weeks after the 15-week weight reducing program, when subjects were weight stable.


RESULTS
In response to weight loss, AT-LPL activity of both regions did not change in men, but decreased in women. Regarding AT-LPL expression, no interaction between time and sex was observed in response to the treatment. In both genders, the higher was the basal AT-LPL activity, the greater was the reduction of this enzyme activity in response to weight loss, in both the abdominal and femoral depots (-0.53<r<-0.84, P values ranging from 0.0001 to 0.05). Body weight loss promoted a significant reduction in plasma triglyceride (TG), insulin and LDL-cholesterol (C) concentrations in men whereas only plasma TG and LDL-C levels were decreased in women (P<0.05). Although the average reduction in HDL-C levels in response to weight loss was not significant, the higher was the decrease in femoral AT-LPL activity, the greater was the reduction in plasma HDL-C levels (r=0.50, P<0.05) in response to weight loss, in women. An inverse relationship was observed between changes in femoral AT-LPL activity and HDL-C levels variation in men (r=-0.64, P<0.05).


CONCLUSIONS
(1) variation in AT-LPL activity differs between men and women in response to moderate body weight loss although the corresponding enzyme mRNA levels remain unchanged; and (2) changes in femoral AT-LPL activity are related to weight loss induced variation in plasma HDL-C concentrations.
Imbeault
P
P
Physical Activity Sciences Laboratory, Department of Social and Preventive Medicine, Québec, Canada.
Alméras
N
N
Richard
D
D
Després
J P
JP
Tremblay
A
A
Mauriège
P
P
D000273:Adipose Tissue / Q000201:enzymology*; D000328:Adult; D001823:Body Composition; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D017931:DNA Primers; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008071:Lipoprotein Lipase / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy / Q000201:enzymology / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012737:Sex Factors; D014280:Triglycerides / Q000097:blood; D015431:Weight Loss / Q000502:physiology*
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D017931:DNA Primers; D007328:Insulin; D012333:RNA, Messenger; D014280:Triglycerides; D008071:Lipoprotein Lipase