Belabed L, Senon G, Blanc M-C, Paillard A, Cynober L, Darquy S
Laboratory of Biological Nutrition, EA 2498, Paris Descartes University, Paris, France.
Diabetologia. 2006 Jun;49(6):1349-59. doi: 10.1007/s00125-006-0233-4. Epub 2006 Apr 19.
AIMS/HYPOTHESIS: 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.
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.
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/INTERPRETATION: Against our working hypothesis, ZDF rats did not show an impaired metabolic response, and even appeared to be less sensitive to the stress.
目的/假设：与肥胖症和2型糖尿病相关的代谢及内分泌紊乱可能会损害机体对损伤的正常代谢反应。我们的目的是研究内毒素血症2型糖尿病肥胖大鼠的氨基酸代谢情况。
对雄性Zucker糖尿病肥胖（ZDF）大鼠（fa/fa）和瘦的同窝大鼠（fa/+）进行了为期4天的代谢研究，将其分为三组：自由采食未接受治疗的组、通过腹腔注射大肠杆菌脂多糖（LPS）进行处理的组以及与相应LPS组配对喂食的组。我们评估了内毒素血症对体重、食物摄入量和组织重量的影响。通过测定尿中3-甲基组氨酸（3-MH）排泄量每日测量氮损失和肌肉蛋白水解情况。测量了血浆、肠道和肌肉中的氨基酸水平。
数据显示，自由采食的ZDF大鼠血浆精氨酸和谷氨酰胺水平低于自由采食的对照大鼠。与对照大鼠相比，经LPS处理的ZDF大鼠胸腺退化程度较低，3-MH与肌酐比值较低，累积氮平衡较高。
结论/解读：与我们的工作假设相反，ZDF大鼠并未表现出代谢反应受损，甚至似乎对应激的敏感性较低。
