Nakashima N, Haji M, Umeda F, Nawata H
Third Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Horm Metab Res. 1995 Nov;27(11):491-4. doi: 10.1055/s-2007-980009.
The effects of dehydroepiandrosterone (DHEA) on glucose uptake and on insulin sensitivity were studied in cultured rat myoblasts (L6 cells). Preincubation with supraphysiological doses of DHEA (10(-5) M approximately significantly enhanced (p < 0.05) the cellular uptake of [3H]-2-deoxyglucose. Glucose uptake was significantly increased in cells exposed to 10(-4)M DHEA for 10 hours (p < 0.005), and for 24 hours (p < 0.001), but not for 3 hours. An increase in DHEA sensitivity with an enhanced glucose uptake was observed in cells exposed to 10(-7)M of human insulin. Insulin sensitivity was increased by preincubating the cells with 10(-6)M of DHEA. Other androgens enhanced the effect on glucose uptake to a lesser extent. DHEA sulfate had no effect on L6 cells, suggesting that the effect may be specific for DHEA, not common to androgens, Sulfation of DHEA may negate the effect. In reciprocal plot analysis, the Km value for glucose transport was decreased by preincubation with DHEA (from 0.67 mM without DHEA, 0.56mM with 10(-5)M DHEA, and 0.25mM with 10(-4) M DHEA), although Vmax was unchanged, We conclude that DHEA increases the affinity of glucose transport in the plasma membrane of cultured rat myoblasts, leading to an enhanced glucose uptake and an increase in insulin sensitivity.
在培养的大鼠成肌细胞（L6细胞）中研究了脱氢表雄酮（DHEA）对葡萄糖摄取和胰岛素敏感性的影响。用超生理剂量的DHEA（10⁻⁵M）预孵育可显著增强（p<0.05）[³H]-2-脱氧葡萄糖的细胞摄取。暴露于10⁻⁴M DHEA 10小时（p<0.005）和24小时（p<0.001）的细胞中葡萄糖摄取显著增加，但3小时时未增加。在暴露于10⁻⁷M人胰岛素的细胞中观察到DHEA敏感性增加以及葡萄糖摄取增强。用10⁻⁶M DHEA预孵育细胞可增加胰岛素敏感性。其他雄激素对葡萄糖摄取的影响较小。硫酸脱氢表雄酮对L6细胞无影响，表明该作用可能对DHEA具有特异性，而非雄激素共有，DHEA的硫酸化可能会消除该作用。在双倒数作图分析中，用DHEA预孵育可降低葡萄糖转运的Km值（未用DHEA时为0.67mM，用10⁻⁵M DHEA时为0.56mM，用10⁻⁴M DHEA时为0.25mM），尽管Vmax不变。我们得出结论，DHEA增加了培养的大鼠成肌细胞质膜中葡萄糖转运的亲和力，导致葡萄糖摄取增强和胰岛素敏感性增加。
