The equivocal metabolic response to endotoxaemia in type 2 diabetic and obese ZDF rats.
OBJECTIVE
The metabolic and endocrine disturbances associated with obesity and type 2 diabetes may impair the normal metabolic response to injury. Our objective was to investigate amino acid metabolism in endotoxaemic type 2 diabetic obese rats.


METHODS
A metabolic study was performed over 4 days using male Zucker diabetic fatty (ZDF) rats (fa/fa) and lean littermates (fa/+) divided into three groups: ad libitum-fed groups which underwent no treatment, lipopolysaccharide (LPS)-treated groups receiving E. coli LPS by i.p. injection, and pair-fed groups to the respective LPS groups. We evaluated the effect of endotoxaemia on body weight, food intake and tissue weights. Nitrogen loss and muscular proteolysis were measured daily by determination of urinary 3-methylhistidine (3-MH) excretion. Plasma, intestine and muscle amino acid levels were measured.


RESULTS
The data showed that ad libitum-fed ZDF rats had lower plasma arginine and glutamine levels than ad libitum-fed control rats. Compared with control rats, the LPS-treated ZDF rats presented lower thymic involution, a lower 3-MH:creatinine ratio and higher cumulative nitrogen balance.


CONCLUSIONS
Against our working hypothesis, ZDF rats did not show an impaired metabolic response, and even appeared to be less sensitive to the stress.
Belabed
L
L
Laboratory of Biological Nutrition, EA 2498, Paris Descartes University, Paris, France. linda.belabed@nutrition-paris5.org
Senon
G
G
Blanc
M-C
MC
Paillard
A
A
Cynober
L
L
Darquy
S
S
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D019446:Endotoxemia / Q000150:complications*; D007413:Intestinal Mucosa / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism; D008070:Lipopolysaccharides / Q000633:toxicity*; D008099:Liver / Q000502:physiology; D008297:Male; D008762:Methylhistidines / Q000652:urine; D009584:Nitrogen / Q000378:metabolism; D009765:Obesity / Q000235:genetics / Q000503:physiopathology*; D051381:Rats; D011924:Rats, Zucker; D012709:Serum Albumin / Q000378:metabolism
D000596:Amino Acids; D008070:Lipopolysaccharides; D008762:Methylhistidines; D012709:Serum Albumin; C028118:3-methylhistidine; D009584:Nitrogen