Effect of hypocaloric diet-induced weight loss in obese women on plasma apelin and adipose tissue expression of apelin and APJ.
OBJECTIVE
Apelin is a novel adipokine acting on APJ receptor, regulated by insulin and tumor necrosis factor-alpha (TNF-alpha) in adipose tissue (AT). Plasma apelin levels are increased in obese hyperinsulinemic subjects. The aim was to investigate whether the hypocaloric diet associated with weight loss modifies the elevated plasma apelin levels and the expression of apelin and APJ receptor in AT in obese women.


METHODS
Fasting plasma levels of apelin and TNF-alpha as well as mRNA levels of apelin and APJ in AT were measured before and after a 12-week hypocaloric weight-reducing diet in 20 obese women (body mass index (BMI) before diet 32.2+/-6.4 kg/m(2)). Twelve healthy women with a BMI of 20.7+/-0.6 kg/m(2) served as reference.


RESULTS
Plasma levels of apelin and TNF-alpha were higher in obese compared with lean controls. The hypocaloric diet resulted in a significant decrease of BMI to 29.8+/-6.3 kg/m(2), plasma insulin (8.16+/-0.73 to 6.58+/-0.66 mU/l), apelin (369+/-25 pg/ml to 257+/-12 pg/ml), TNF-alpha levels (0.66+/-0.04 pg/ml to 0.56+/-0.04 pg/ml), and AT mRNAs of apelin and APJ. In addition, changes in AT mRNA apelin were related to changes in AT mRNA APJ levels.


CONCLUSIONS
The hypocaloric diet associated with weight loss reduces the increased plasma and AT expression of apelin in obese women. This reduced apelin expression in AT could contribute to decreased circulating apelin levels.
Castan-Laurell
Isabelle
I
Inserm, U858 Equipe 3, Institut de Médecine Moléculaire de Rangueil, BP84225, Toulouse F-31432 Cedex 4, France. isabelle.castan@toulouse.inserm.fr
Vítkova
Michaela
M
Daviaud
Danièle
D
Dray
Cédric
C
Kováciková
Michaela
M
Kovacova
Zuzana
Z
Hejnova
Jindriska
J
Stich
Vladimir
V
Valet
Philippe
P
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000073861:Apelin; D000075244:Apelin Receptors; D050528:Diet, Carbohydrate-Restricted / Q000379:methods*; D005260:Female; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood* / Q000378:metabolism; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000178:diet therapy* / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000097:blood* / Q000378:metabolism; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss
C115436:APLN protein, human; C104575:APLNR protein, human; D000073861:Apelin; D000075244:Apelin Receptors; D036341:Intercellular Signaling Peptides and Proteins; D043562:Receptors, G-Protein-Coupled