Regional variations in HDL metabolism in human fat cells: effect of cell size

Journal Article · Fri May 01 04:00:00 EDT 1987 · Am. J. Physiol.; (United States)

OSTI ID:5767532

Despres, J; Fong, B S; Julien, P; Jimenez, J; Angel, A

Abdominal obesity is related to reduced plasma high-density lipoprotein (HDL) cholesterol, and both are associated with cardiovascular disease risk. The authors have observed that plasma membranes from abdominal subcutaneous adipocytes have a greater HDL binding capacity than omental fat cell plasma membranes. The present study examined whether these binding characteristics could be due to differences in fat cell size or cholesterol concentration between the two adipose depots. Abdominal subcutaneous and deep omental fat were obtained from massively obese patients at surgery. Subcutaneous abdominal fat cells were significantly larger and their cellular cholesterol content greater than omental adipocytes. The uptake of HDL by collagenase-isolated fat cells was studied by incubating the cells for 2 h at 37/sup 0/C with 10 ..mu..g/ml /sup 125/I-HDL/sub 2/ or /sup 125/I-HDL/sub 3/. In both depots, the cellular uptake of /sup 125/I-HDL/sub 2/ and /sup 125/I-HDL/sub 3/ was specifically inhibited by addition of 25-fold excess unlabeled HDL and a close correlation was observed between the cellular uptake of /sup 125/I-HDL/sub 2/ and /sup 125/I-HDL/sub 3/. In obese patients, the uptake of /sup 125/I-HDL was higher in subcutaneous cells than in omental cells. The cellular /sup 125/I-HDL uptake was significantly correlated with adipocyte size and fat cell cholesterol content but not with adipocyte cholesterol concentration. These results suggest that the higher HDL uptake observed in subcutaneous cells compared with omental cells in obesity is the result of differences in adipocyte size rather than differences in the cholesterol concentration (cholesterol-to-triglyceride ratio). The increased interaction of HDL with hypertrophied abdominal adipocytes may play an important role in determining the lipid composition of HDL in obesity.

• Research Organization: Univ. of Toronto, Ontario
• OSTI ID: 5767532
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 252:5; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADIPOSE TISSUE
ANIMAL CELLS
ANIMAL TISSUES
BETA DECAY RADIOISOTOPES
BIOPSY
BODY
CELL CONSTITUENTS
CELL MEMBRANES
CHOLESTEROL
CONNECTIVE TISSUE
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
DIAGNOSTIC TECHNIQUES
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
FAT CELLS
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
LABELLED COMPOUNDS
LIPIDS
LIPOPROTEINS
MEMBRANES
METABOLIC DISEASES
METABOLISM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PATHOGENESIS
PATIENTS
PROTEINS
RADIOISOTOPES
SIZE
SOMATIC CELLS
STEROIDS
STEROLS
TISSUES
UPTAKE