Plasma adiponectin levels are not associated with fat oxidation in humans.
OBJECTIVE
To test the hypothesis that low adiponectin is associated with low fat oxidation in humans.


METHODS
We measured plasma adiponectin concentrations in 75 healthy, nondiabetic Pima Indians (age, 28 +/- 7 years; 55 men and 20 women; body fat, 29.7 +/- 7.5%) and 18 whites [(age, 33 +/- 8 years; 14 men and 4 women; body fat, 28.2 +/- 10.8% (means +/- SD)] whose body composition was measured by DXA and 24-hour energy expenditure (24-hour EE) by a respiratory chamber. Respiratory quotient (an estimate of whole-body carbohydrate/lipid oxidation rate) was calculated over 24 hours (24-hour RQ).


RESULTS
Before correlational analyses, waist-to-thigh ratio (WTR) and percentage of body fat (PFAT) were adjusted for age, sex, and race; 24-hour EE was adjusted for fat mass and fat-free mass, and 24-hour RQ were adjusted for energy balance. Plasma adiponectin concentrations were negatively correlated with WTR (r = -0.42, p < 0.0001) and PFAT (r = -0.46, p < 0.0001). There was no correlation between plasma adiponectin concentrations and 24-hour RQ, (r = 0.09, p = 0.36) before or after adjustment for PFAT (r = 0.001, p = 0.99, respectively, partial correlation), and no correlation was found between plasma adiponectin concentrations and 24-hour EE (r = -0.12, p = 0.27).


CONCLUSIONS
Our cross-sectional data do not suggest physiological concentrations of fasting plasma adiponectin play a role in the regulation of whole-body fat oxidation or energy expenditure in resting conditions. Whether administration of adiponectin to individuals with low levels of this hormone will increase their fat oxidation rates/energy expenditure remains to be established.
Stefan
Norbert
N
Clinical Diabetes and Nutrition Section, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, Arizona 85016, USA. nstefan@mail.nih.gov
Vozarova
Barbora
B
Funahashi
Tohru
T
Matsuzawa
Yuji
Y
Ravussin
Eric
E
Weyer
Christian
C
Tataranni
P Antonio
PA
D015502:Absorptiometry, Photon; D052242:Adiponectin; D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000502:physiology; D002153:Calorimetry, Indirect; D015331:Cohort Studies; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007198:Indians, North American; D007328:Insulin / Q000097:blood / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins; D008297:Male; D011506:Proteins / Q000378:metabolism*; D044465:White People
D052242:Adiponectin; D001786:Blood Glucose; D007328:Insulin; D036341:Intercellular Signaling Peptides and Proteins; D011506:Proteins