Paolisso G, Sgambato S, Gambardella A, Pizza G, Tesauro P, Varricchio M, D'Onofrio F
Department of Geriatric Medicine and Metabolic Diseases, 1st Medical School, University of Naples, Italy.
Am J Clin Nutr. 1992 Jun;55(6):1161-7. doi: 10.1093/ajcn/55.6.1161.
We demonstrated similar plasma concentrations and urinary losses but lower erythrocyte magnesium concentrations (2.18 +/- 0.04 vs 1.86 +/- 0.03 mmol/L, P less than 0.01) in twelve aged (77.8 +/- 2.1 y) vs 25 young (36.1 +/- 0.4 y), nonobese subjects. Subsequently, aged subjects were enrolled in a double-blind, randomized, crossover study in which placebo (for 4 wk) and chronic magnesium administration (CMA) (4.5 g/d for 4 wk) were provided. At the end of each treatment period an intravenous glucose tolerance test (0.33 g/kg body wt) and a euglycemic glucose clamp with simultaneous [D-3H]glucose infusion and indirect calorimetry were performed. CMA vs placebo significantly increased erythrocyte magnesium concentration and improved insulin response and action. Net increase in erythrocyte magnesium significantly and positively correlated with the decrease in erythrocyte membrane microviscosity and with the net increase in both insulin secretion and action. In aged patients, correction of a low erythrocyte magnesium concentration may allow an improvement of glucose handling.
我们在12名老年（77.8±2.1岁）和25名年轻（36.1±0.4岁）非肥胖受试者中发现，血浆镁浓度和尿镁排泄量相似，但红细胞镁浓度较低（分别为2.18±0.04和1.86±0.03 mmol/L，P<0.01）。随后，老年受试者参加了一项双盲、随机、交叉研究，该研究提供了安慰剂（为期4周）和慢性镁给药（CMA）（4.5 g/d，为期4周）。在每个治疗期结束时，进行了静脉葡萄糖耐量试验（0.33 g/kg体重）以及同时进行[D-3H]葡萄糖输注和间接测热法的正常血糖葡萄糖钳夹试验。与安慰剂相比，CMA显著提高了红细胞镁浓度，并改善了胰岛素反应和作用。红细胞镁的净增加与红细胞膜微粘度的降低以及胰岛素分泌和作用的净增加显著正相关。在老年患者中，纠正低红细胞镁浓度可能有助于改善葡萄糖代谢。
