Effect of weight loss on whole-body and cellular lipid metabolism
in severely obese humans.
Klein, Samuel, Kham Luu, Slavisa Gasic, Allan Green.
Department of Internal Medicine, Washington University School of
Medicine, St. Louis, MO 63110 and Department of Internal Medicine,
The University of Texas Medical Branch, Galveston, TX 77555
APStracts 2:0255E, 1995.
We evaluated the effect of diet-induced weight loss on whole body and
cellular lipid metabolism in persons with severe upper body obesity
in two study protocols. In protocol 1, palmitate and glycerol rates
of appearance (Ra) in plasma were determined during basal conditions
in seven subjects (initial BMI = 41.3+/-2.2kg/m2) before and after a
20.4+/-3.0 kg weight loss. Total glycerol and palmitate Ra decreased
from 231.0+/-19.4 and 166.2+/-16.6 [mu]mol.min-1, respectively,
before weight loss to 162.7+/-9.5 and 105.0+/-9.7 [mu]mol.min-1,
respectively, after weight loss (p< 0.01). However, glycerol and
palmitate Ra expressed per kg fat mass were similar both before and
after weight loss. In protocol 2, subcutaneous abdominal adipose
tissue was obtained before and after a 14.4+/-2.1 kg weight loss in
five subjects (initial BMI = 41.6+/-2.6kg/m2). Weight loss caused a
38+/-8% decrease in adipocyte hormone-sensitive lipase concentration
(p<0.05) but was not associated with any consistent changes in
the concentrations of GTP-dependent regulatory proteins, Gi1[alpha],
Gi2[alpha], and Gsa. We conclude that diet-induced weight loss
ameliorates the increase in basal lipolytic rates in persons with
severe upper-body obesity. These alterations are associated with
changes in cellular hormone sensitive lipase but not GTP-dependent
regulatory protein concentrations.
Received 23 August 1995; accepted in final form 6 December 1995.
APS Manuscript Number E408-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 December 95