Department of Food Science, University of Massachusetts, Amherst, 100 Holdsworth Way, Amherst, MA 01003, USA.
J Bone Miner Metab. 2011 May;29(3):268-78. doi: 10.1007/s00774-010-0212-1. Epub 2010 Aug 10.
Dietary conjugated linoleic acid (CLA) has shown wide biologically beneficial effects, such as anticancer, antiatherosclerotic, antidiabetic, immunomodulating, and antiobesity effects. However, the effects of CLA on total body ash, reflective of bone mineral content, have not been consistent. We hypothesized that the inconsistency of the CLA effect on ash may be linked to interaction between CLA and dietary calcium levels. Thus, we investigated the effects of CLA on body ash in conjunction with various calcium levels. Male ICR mice were fed three different levels of calcium (0.01, 0.5, and 1%) with or without 0.5% CLA for 4 weeks for Experiment 1 and separate CLA isomers at 0.22% level with 1% calcium in Experiment 2. CLA feeding reduced body fat regardless of dietary calcium level, whereas CLA supplementation increased body ash compared to control only in animals fed the 1% calcium. In Experiment 2 it was confirmed that this observation was associated with the trans-10, cis-12 CLA isomer, but not with the cis-9, trans-11 isomer. CLA administration with 1% dietary calcium significantly improved total ash percent (%) in femurs, confirming that CLA has the potential to be used to improve bone mass.
饮食共轭亚油酸（CLA）已显示出广泛的有益生物学效应，如抗癌、抗动脉粥样硬化、抗糖尿病、免疫调节和抗肥胖作用。然而，CLA 对总体灰分（反映骨矿物质含量）的影响并不一致。我们假设 CLA 对灰分的影响不一致可能与 CLA 与膳食钙水平之间的相互作用有关。因此，我们研究了 CLA 与各种钙水平结合对体灰分的影响。雄性 ICR 小鼠在实验 1 中分别用 0.01、0.5 和 1%三种不同的钙水平和或 0.5% CLA 喂养 4 周，在实验 2 中用 1%的钙和 0.22%的 CLA 异构体喂养。无论饮食钙水平如何，CLA 喂养均可减少体脂肪，而 CLA 补充仅在动物食用 1%钙时与对照组相比增加了体灰分。在实验 2 中证实，这种观察结果与反式 10，顺式 12 CLA 异构体有关，而与顺式 9，反式 11 异构体无关。CLA 与 1%膳食钙联合使用可显著提高股骨总灰分（%），证实 CLA 具有增加骨量的潜力。
