Change in beta1-adrenergic receptor protein concentration in adipose tissue correlates with diet-induced weight loss.
The aim of the present study was to examine gene expression and protein concentrations of beta(1)- and beta(2)-adrenergic receptors in subcutaneous adipose tissue in obese subjects in response to weight loss. Eighteen obese subjects were studied during diet-induced weight loss. Beta-adrenergic receptor mRNA levels were quantified by reverse transcription-PCR-HPLC. Beta-adrenergic receptor protein concentrations were measured by Western blotting using fluorescence laser scanning for detection. Subjects lost 12.8+/-0.8 kg (mean+/-S.E.M.) during diet treatment. There was a 34% decrease in the beta(1)-adrenergic receptor mRNA level (0.92+/-0.09 compared with 0.61+/-0.06 amol/microg of DNA; P<0.002). Beta(2)-adrenergic receptor mRNA did not decrease significantly. Beta(2)-adrenergic receptor protein concentration decreased 37% (25.5+/-7.1 compared with 16.0+/-5.6 arbitrary units/ng of DNA; P=0.008), whereas beta(1)-adrenergic receptor protein concentration did not decrease significantly. The degree of weight loss was correlated with the concentration of beta(1)-adrenergic receptor protein (r=0.65, P<0.003) and changes in receptor protein concentration (r=0.50, P=0.035) during the very-low-calorie diet. In conclusion, the present study demonstrates a relationship between beta(1)-adrenergic receptor protein concentration in adipose tissue and the degree of weight loss. This relationship is not directly related to energy expenditure and deserves further investigation.
Rasmussen
Mads
M
Department of Endocrinology, Herlev Hospital, University of Copenhagen, 2730 Herlev, Denmark. mads.rasmussen@dadlnet.dk
Belza
Anita
A
Almdal
Thomas
T
Toubro
Søren
S
Bratholm
Palle
P
Astrup
Arne
A
Christensen
Niels J
NJ
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000886:Anthropometry; D015153:Blotting, Western; D015992:Body Mass Index; D004038:Diet, Reducing; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D009765:Obesity / Q000178:diet therapy / Q000378:metabolism* / Q000503:physiopathology; D012333:RNA, Messenger / Q000235:genetics; D018342:Receptors, Adrenergic, beta-1 / Q000235:genetics / Q000378:metabolism*; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D015431:Weight Loss
D012333:RNA, Messenger; D018342:Receptors, Adrenergic, beta-1; D018343:Receptors, Adrenergic, beta-2