Department of Kinesiology, School of Public Health, University of Maryland College Park, MD 20742, USA.
Metabolism. 2011 Feb;60(2):265-71. doi: 10.1016/j.metabol.2010.01.026. Epub 2010 Mar 4.
Fetuin-A is a liver-derived factor that may play a role in insulin resistance and age-related chronic diseases (eg, type 2 diabetes mellitus and cardiovascular [CV] disease). Regular exercise improves CV risk and insulin sensitivity; however, it is unknown whether chronic exercise training is related to circulating levels of fetuin-A. Therefore, this study examined whether plasma fetuin-A levels were related to age and chronic physical activity in men. We hypothesized that chronic physical activity would be related to lower plasma fetuin-A levels in younger and older men. In healthy high-active (HI) and low-active (LO) young (HI, n = 7; LO, n = 8) and older (HI, n = 12, LO, n = 11) men, we determined cardiorespiratory fitness (maximal oxygen uptake), plasma fetuin-A levels, plasma insulin, insulin resistance (homeostasis model assessment of insulin resistance), and the standard risk factors for CV disease. Groups were matched for body mass index. Fetuin-A was significantly higher (~20%) in both young and older LO men compared with their HI counterparts, and fetuin-A was inversely related to maximal oxygen uptake (r = -0.40, P = .014). Plasma fetuin-A levels showed trends to be significantly correlated with insulin (r = -0.34, P = .052) and homeostasis model assessment of insulin resistance (r = 0.33, P = .058) in the older individuals. In younger participants, fetuin-A was related to blood pressure and cholesterol measures. These results indicate that low levels of fetuin-A are related to cardiorespiratory fitness and a number of conventional CV and metabolic disease risk factors independent of age and body mass index. Therefore, the maintenance of low levels of circulating fetuin-A may be a novel mechanism contributing to enhanced insulin sensitivity with regular physical activity.
胎球蛋白 A 是一种肝脏来源的因子，可能在胰岛素抵抗和与年龄相关的慢性疾病（如 2 型糖尿病和心血管疾病）中发挥作用。有规律的运动可以改善心血管风险和胰岛素敏感性；然而，目前尚不清楚慢性运动训练是否与胎球蛋白 A 的循环水平有关。因此，本研究探讨了血浆胎球蛋白 A 水平与男性年龄和慢性体力活动的关系。我们假设慢性体力活动与年轻和老年男性的血浆胎球蛋白 A 水平较低有关。在健康的高活跃（HI）和低活跃（LO）的年轻（HI，n = 7；LO，n = 8）和老年（HI，n = 12，LO，n = 11）男性中，我们测定了心肺功能（最大摄氧量）、血浆胎球蛋白 A 水平、血浆胰岛素、胰岛素抵抗（胰岛素抵抗稳态模型评估）以及心血管疾病的标准危险因素。组间匹配了体重指数。年轻和老年 LO 男性的胎球蛋白 A 水平均显著高于其 HI 对应者（约 20%），胎球蛋白 A 与最大摄氧量呈负相关（r = -0.40，P =.014）。在老年个体中，血浆胎球蛋白 A 水平与胰岛素（r = -0.34，P =.052）和胰岛素抵抗稳态模型评估（r = 0.33，P =.058）呈显著相关趋势。在年轻参与者中，胎球蛋白 A 与血压和胆固醇指标有关。这些结果表明，低水平的胎球蛋白 A 与心肺功能以及许多传统的心血管和代谢疾病危险因素有关，与年龄和体重指数无关。因此，循环胎球蛋白 A 水平的维持较低可能是有规律的体力活动增强胰岛素敏感性的一个新机制。
