Fischer S, Hanefeld M, Haffner S M, Fusch C, Schwanebeck U, Köhler C, Fücker K, Julius U
Institute of Clinical Metabolic Research, Medical Faculty Carl Gustav Carus, University of Technology Dresden, Fetscherstrasse 74, 01307 Dresden, Germany.
Acta Diabetol. 2002 Sep;39(3):105-10. doi: 10.1007/s005920200027.
In obese people, an increase of plasma leptin levels is well-known and is seen as a consequence of the increased body fat mass. Moreover, a relationship between fasting concentrations of leptin and insulin has been described. Hyperinsulinemia is considered to be indicative of insulin resistance. We aimed at elucidating the interrelations between leptin, insulin and insulin resistance in type 2 diabetic patients. Under metabolic ward conditions, we investigated 21 moderately overweight men with type 2 diabetes. The patients had a mean age of 49.1 years, a mean body mass index (BMI) of 26.8 kg/m(2), and a mean diabetes duration of 82.5 months. All patients were treated with diet alone. We measured fasting leptin and insulin levels, body composition by determination of total body water, and insulin resistance by euglycemic hyperinsulinemic clamp technique. At univariate analysis, fasting leptin level significantly and positively correlated with BMI (r=0.49, p=0.02) and with fasting insulin (r=0.69, p=0.001), while it negatively correlated with the glucose disposal rate (r=-0.62, p=0.002). Furthermore, leptin was inversely correlated with HDL-cholesterol (r=-0.45, p=0.04). When excluding the influence of body fat mass or of BMI in partial correlation analysis, the correlations between leptin and insulin or insulin sensitivity remained significant. The relationship between insulin resistance (as measured directly in the clamp experiments) and leptin concentrations was also shown by subdividing the diabetic patients according to tertiles of insulin sensitivity. The highest fasting leptin levels were observed in those patients with the most expressed insulin resistance. Our data point to a functional relationship between insulin resistance and leptin concentrations in insulin-resistant type 2 diabetic men, independently of body composition. This relationship is believed to be mediated by insulin.
在肥胖人群中，血浆瘦素水平升高是众所周知的，并且被视为体脂量增加的结果。此外，已经描述了瘦素的空腹浓度与胰岛素之间的关系。高胰岛素血症被认为是胰岛素抵抗的指标。我们旨在阐明2型糖尿病患者中瘦素、胰岛素和胰岛素抵抗之间的相互关系。在代谢病房条件下，我们调查了21名中度超重的2型糖尿病男性患者。这些患者的平均年龄为49.1岁，平均体重指数（BMI）为26.8kg/m²，平均糖尿病病程为82.5个月。所有患者均仅接受饮食治疗。我们测量了空腹瘦素和胰岛素水平，通过测定总体水来测量身体成分，并通过正常血糖高胰岛素钳夹技术测量胰岛素抵抗。在单变量分析中，空腹瘦素水平与BMI显著正相关（r = 0.49，p = 0.02），与空腹胰岛素正相关（r = 0.69，p = 0.001），而与葡萄糖处置率负相关（r = -0.62，p = 0.002）。此外，瘦素与高密度脂蛋白胆固醇呈负相关（r = -0.45，p = 0.04）。在偏相关分析中排除体脂量或BMI的影响后，瘦素与胰岛素或胰岛素敏感性之间的相关性仍然显著。根据胰岛素敏感性三分位数对糖尿病患者进行细分，也显示了胰岛素抵抗（如在钳夹实验中直接测量）与瘦素浓度之间的关系。在胰岛素抵抗最明显的患者中观察到最高的空腹瘦素水平。我们的数据表明，在胰岛素抵抗的2型糖尿病男性中，胰岛素抵抗与瘦素浓度之间存在功能关系，与身体成分无关。这种关系被认为是由胰岛素介导的。
