Gene expression of adiponectin receptors in human visceral and subcutaneous adipose tissue is related to insulin resistance and metabolic parameters and is altered in response to physical training.
OBJECTIVE
Adiponectin receptors 1 and 2 (AdipoR1 and AdipoR2, respectively) mediate the effects of adiponectin on glucose and lipid metabolism in vivo. We examined whether AdipoR1 and/or AdipoR2 mRNA expression in human adipose tissue is fat-depot specific. We also studied whether their expression in visceral and subcutaneous fat depots is associated with metabolic parameters and whether their expression is regulated by intensive physical exercise.


METHODS
We determined metabolic parameters and assessed AdipoR1 and AdipoR2 mRNA expression using quantitative real-time PCR in adipose tissue in an observational study of 153 subjects and an interventional study of 60 subjects (20 each with normal glucose tolerance, impaired glucose tolerance, and type 2 diabetes) before and after intensive physical training for 4 weeks.


RESULTS
AdipoR1 and AdipoR2 mRNA expression is not significantly different between omental and subcutaneous fat, but their expression is several-fold lower in adipose tissue than in muscle. AdipoR2 mRNA expression in visceral fat is highly correlated with its expression in subcutaneous fat. AdipoR2 mRNA expression in both visceral and subcutaneous fat is positively associated with circulating adiponectin and HDL levels but negatively associated with obesity as well as parameters of insulin resistance, glycemia, and other lipid levels before and after adjustment for fat mass. Physical training for 4 weeks resulted in increased AdipoR1 and AdipoR2 mRNA expression in subcutaneous fat.


CONCLUSIONS
AdipoR2 mRNA expression in fat is negatively associated with insulin resistance and metabolic parameters independently of obesity and may mediate the improvement of insulin resistance in response to exercise.
Blüher
Matthias
M
Department of Internal Medicine III, University of Leipzig, Leipzig, Germany.
Williams
Catherine J
CJ
Klöting
Nora
N
Hsi
Alex
A
Ruschke
Karen
K
Oberbach
Andreas
A
Fasshauer
Mathias
M
Berndt
Janin
J
Schön
Michael R
MR
Wolk
Alicja
A
Stumvoll
Michael
M
Mantzoros
Christos S
CS
D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000502:physiology* / Q000503:physiopathology*; D050110:Bariatric Surgery; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics / Q000601:surgery; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics / Q000601:surgery; D015444:Exercise; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D008297:Male; D009765:Obesity / Q000235:genetics / Q000601:surgery; D012333:RNA, Messenger / Q000235:genetics; D054419:Receptors, Adiponectin / Q000235:genetics*; D044465:White People
C475418:ADIPOR1 protein, human; C475420:ADIPOR2 protein, human; D012333:RNA, Messenger; D054419:Receptors, Adiponectin