Journal of Lipid Research, Vol 22, 72-80, Copyright © 1981 by Lipid Research, Inc.

ARTICLES

Effects of cell size and animal age on glucose metabolism in pig adipose tissue

TD Etherton, ED Aberle, EH Thompson and CE Allen

Adipose tissue slices were prepared from middle subcutaneous or perirenal adipose tissue excised from pigs of different ages (and obesity) and incubated with [U-14C]glucose. After incubation, the slices were fixed with osmium tetroxide and separated into diameter ranges of 20--63, 63--102, and 102--153 microgram, respectively. Following determination of cell size and number, the fixed adipocytes were decolorized with H2O2 prior to quantification of glucose conversion to total lipid, glyceride fatty acids, glycerideglycerol, and CO2. Glucose conversion to total lipid or CO2 was unaffected by the presence of purified porcine insulin (0, 10, 100, 1000, and 100,000 microM/ml). Within animals, adipocytes of different sizes were not different with regard to insulin sensitivity. Within a weight (age) group, conversion of glucose to total lipid (insulin present) or to glyceride fatty acids and glyceride-glycerol (insulin absent) per cell was significantly greater in large adipocytes compared to small adipocytes, regardless of the group examined. With increasing weight or age, there was a markedly decreased conversion of glucose to total lipid and glyceride fatty acids among adipocytes of similar size within a cell-size fraction. The diminution in glucose metabolism was greater (as a percentage) in 20--63 microgram adipocytes than for 63--102 or 102--153 microgram adipocytes. However, for all cell-size fractions there was a marked decrease in glucose conversion to fatty acids. Glyceride-glycerol synthesis was impaired in adipocytes from older pigs, but the decrease was less than observed for glyceride fatty acid synthesis.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				D. Gardan, F. Gondret, and I. Louveau Lipid metabolism and secretory function of porcine intramuscular adipocytes compared with subcutaneous and perirenal adipocytes Am J Physiol Endocrinol Metab, August 1, 2006; 291(2): E372 - E380. [Abstract] [Full Text] [PDF]

				T. G. Ramsay and M. P. Richards Hormonal regulation of leptin and leptin receptor expression in porcine subcutaneous adipose tissue J Anim Sci, December 1, 2004; 82(12): 3486 - 3492. [Abstract] [Full Text] [PDF]

				K.-Y. Guo, P. Halo, R. L. Leibel, and Y. Zhang Effects of obesity on the relationship of leptin mRNA expression and adipocyte size in anatomically distinct fat depots in mice Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2004; 287(1): R112 - R119. [Abstract] [Full Text] [PDF]

				Y. Zhang, K.-Y. Guo, P. A. Diaz, M. Heo, and R. L. Leibel Determinants of leptin gene expression in fat depots of lean mice Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2002; 282(1): R226 - R234. [Abstract] [Full Text] [PDF]