Change in plasma acylation stimulating protein during euglycaemic-hyperinsulinaemic clamp in overweight and obese postmenopausal women: a MONET study.
OBJECTIVE
Acylation-stimulating protein (ASP) has been shown to positively stimulate fatty acid esterification and glucose uptake in adipocytes. In vitro studies demonstrate that insulin stimulates ASP secretion from adipocytes. Individuals with obesity and/or metabolic disturbances (insulin resistance and type 2 diabetes) have increased plasma ASP.


METHODS
The present study was designed to evaluate whether ASP levels are influenced by the metabolic profiles of overweight and obese postmenopausal women during a euglycaemic/hyperinsulinaemic clamp (EHC). Patients The study population consisted of 76 overweight and obese sedentary postmenopausal women.


METHODS
We evaluated insulin sensitivity, plasma ASP levels, body composition including visceral adipose tissue area, blood lipid profiles, liver enzymes, peak aerobic capacity, resting metabolic rate (RMR) and total energy expenditure (TEE).


RESULTS
We observed wide interindividual variations of ASP levels during the EHC. Therefore, subjects were divided into three groups based on ASP changes. Negative ASP Responders (NAR; n = 24) showed a -20% or greater decrease in ASP levels while Positive ASP Responders (PAR; n = 42) displayed ASP fluctuations superior to +20%. Ten subjects had little or no ASP change and were considered as Zero ASP responders (ZAR). PAR women displayed a worse metabolic profile than NAR women, including higher BMI, visceral adipose tissue, fasting insulin levels, lean body mass, and alanine aminotransferase (ALT), a marker of impaired liver function. After adjustment for BMI, only ALT remained significantly different, while lean body mass (P = 0.08) and visceral adipose tissue (P = 0.07) remained marginally higher. Correlation analysis of all subjects demonstrated that fasting ASP levels correlated positively with albumin and VO(2 peak) and this association remained significant after adjustments for the effect of BMI. In addition, the percentage maximal change in ASP levels during the EHC was positively associated with BMI, lean body mass, visceral adipose tissue, fasting insulin, HOMA, TEE, RMR, ALT and AST.


CONCLUSIONS
Overall these results suggest that an elevated ASP response during the EHC is associated with metabolic disturbances in overweight and obese postmenopausal women.
St-Pierre
David H
DH
Département de Nutrition, Université de Montréal, Montréal, Québec, Canada.
Cianflone
Katherine
K
Smith
Jessica
J
Coderre
Lise
L
Karelis
Antony D
AD
Imbeault
Pascal
P
Lavoie
Jean-Marc
JM
Rabasa-Lhoret
Rémi
R
D017667:Adipocytes / Q000378:metabolism; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D001481:Basal Metabolism / Q000502:physiology; D001823:Body Composition / Q000502:physiology; D015992:Body Mass Index; D003176:Complement C3; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood* / Q000209:etiology / Q000503:physiopathology; D007328:Insulin / Q000097:blood; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000503:physiopathology; D050177:Overweight / Q000097:blood* / Q000503:physiopathology; D010101:Oxygen Consumption / Q000502:physiology; D017698:Postmenopause / Q000097:blood* / Q000502:physiology; D011446:Prospective Studies; D011792:Quebec
D003176:Complement C3; D007328:Insulin; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase