High expression of complement components in omental adipose tissue in obese men.
Artikel i vetenskaplig tidskrift, 2003

OBJECTIVE: Accumulation of visceral fat is recognized as a predictor of obesity-related metabolic disturbances. Factors that are predominantly expressed in this depot could mediate the link between visceral obesity and associated diseases. RESEARCH METHODS AND PROCEDURES: Paired subcutaneous and omental adipose tissue biopsies were obtained from 10 obese men. Gene expression was analyzed by DNA microarrays in triplicate and by real-time polymerase chain reaction. Serum C3 and C4 were analyzed by radial immunodiffusion assays in 91 subjects representing a cross section of the general population. Body composition was measured by computerized tomography. RESULTS: Complement components C2, C3, C4, C7, and Factor B had higher expression in omental compared with subcutaneous adipose tissue ( approximately 2-, 4-, 17-, 10-, and 7-fold, respectively). In addition, adipsin, which belongs to the alternative pathway, and the classical pathway components C1QB, C1R, and C1S were expressed in both depots. Analysis of tissue distribution showed high expression of C2, C3, and C4 in omental adipose tissue, and only liver had higher expression of these genes. Serum C3 levels correlated with both visceral and subcutaneous adipose tissue in both men (r = 0.65 and p < 0.001 and r = 0.52 and p < 0.001, respectively) and women (r = 0.34 and p = 0.023 and r = 0.49 and p < 0.001, respectively), whereas C4 levels correlated with only visceral fat in men (r = 0.36, p = 0.015) and with both depots in women (visceral: r = 0.58, p < 0.001; and subcutaneous: r = 0.51, p < 0.001). DISCUSSION: Recent studies show that the metabolic syndrome is associated with chronically elevated levels of several immune markers, some of which may have metabolic effects. The high expression of complement genes in intra-abdominal adipose tissue might suggest that the complement system is involved in the development of visceral adiposity and/or contributes to the metabolic complications associated with increased visceral fat mass.

genetics

Complement C2

Gene Expression

Male

Complement Factor B

Complement C3

Oligonucleotide Array Sequence Analysis

genetics

Complement C1q

Serine Endopeptidases

Polymerase Chain Reaction

Adipose Tissue

metabolism

genetics

Humans

Obesity

genetics

chemistry

genetics

Complement C7

Complement Factor D

Complement C1s

Complement C1r

Complement System Proteins

genetics

Complement C4

Omentum

genetics

Adult

genetics

genetics

Middle Aged

genetics

Författare

Britt Gabrielsson

Göteborgs universitet

Jenny Palming

Göteborgs universitet

Malin Lönn

Göteborgs universitet

Margareta Jernås

Göteborgs universitet

Torsten Olbers

Göteborgs universitet

Markku Peltonen

Göteborgs universitet

Ingrid Larsson

Göteborgs universitet

Lars Lönn

Göteborgs universitet

Lars Sjöström

Göteborgs universitet

Björn Carlsson

Göteborgs universitet

Lena M S Carlsson

Göteborgs universitet

Obesity Research

1071-7323 (ISSN) 1550-8528 (eISSN)

Vol. 11 699-708

Ämneskategorier

Dermatologi och venereologi

Medicinsk genetik

DOI

10.1038/oby.2003.100

PubMed

12805391