Söderberg Lars, Haag Linnea, Höglund Peter, Roth Bodil, Stenberg Pål, Wahlgren Marie
Hospital Pharmacy, Malmö University Hospital, Malmö, Sweden; Department of Food Technology, Lund University, Lund, Sweden.
Eur J Pharm Sci. 2009 Mar 2;36(4-5):458-64. doi: 10.1016/j.ejps.2008.11.011. Epub 2008 Dec 3.
Low aqueous solubility of lipophilic agents, such as free fatty acids, hampers proper in vitro demonstration of biological effects, yielding an ambiguous in vitro-in vivo correlation. We have therefore developed a method for evaluating the acute effects of lipophilic substances on the shape of erythrocytes and estimated EC(50) and Hill coefficient according to the sigmoidal E(max) model. The test substance dissolved in medium-chain triglyceride is coated on a polycarbonate slide which serves as a cover sheet of a Bürker chamber. Freshly collected finger-tip blood is diluted with autologous EDTA-plasma and introduced into the chamber. After 10min at 37 degrees C, the cells are photographed under microscope and the fractions of normal and defect cells are evaluated. No staining is needed and the cells are kept viable during the test period. With increasing chain length, fatty acids, aliphatic amines and alcohols all increased the fraction of defect erythrocytes in a concentration-dependent manner. The results indicate that several fatty acids are very potent in their acute actions on erythrocytes, and that this effect is due to chain length rather than conformation.
The technique offers a screening method for testing the harmful effects of small amounts of lipophilic substances on erythrocytes.
亲脂性物质，如游离脂肪酸，在水中的溶解度较低，这妨碍了其生物学效应在体外的恰当展示，导致体外-体内相关性不明确。因此，我们开发了一种方法来评估亲脂性物质对红细胞形态的急性影响，并根据S形E(max)模型估算半数有效浓度（EC(50)）和希尔系数。将溶解于中链甘油三酯的受试物质涂覆在用作 Bürker 计数板盖片的聚碳酸酯载玻片上。用自体乙二胺四乙酸（EDTA）血浆稀释新鲜采集的指尖血，然后引入计数板。在37℃下放置10分钟后，在显微镜下对细胞进行拍照，并评估正常细胞和缺陷细胞的比例。无需染色，且细胞在测试期间保持存活。随着链长增加，脂肪酸、脂肪族胺和醇类均以浓度依赖的方式增加了缺陷红细胞的比例。结果表明，几种脂肪酸对红细胞的急性作用非常显著，且这种作用归因于链长而非构象。
该技术为检测少量亲脂性物质对红细胞的有害作用提供了一种筛选方法。
