Iglesias Bernardo Fabricio, Catalá Angel
Cátedra de Bioquímica, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, CC 296, B1900 AVW, La Plata, Argentina.
Res Vet Sci. 2005 Aug;79(1):19-27. doi: 10.1016/j.rvsc.2004.10.004. Epub 2004 Dec 21.
The aim of the present study was to analyze the time-course of t-butyl hydroperoxide-induced changes in lipid peroxidation, fatty acid composition and chemiluminescence intensity in rat, caprine, equine and bovine erythrocyte ghosts. A relatively high content of arachidonic acid (C20:4 n6) and docosahexaenoic acid (C22:6 n3) was characteristic of the rat erythrocyte ghosts. The fatty acid composition of native erythrocyte ghosts obtained from caprine, equine and bovine was characterized by a high content of oleic acid (C18:1 n9) and a low content of the peroxidable polyunsaturated fatty acids (C20:4 n6 and C22:6 n3). The proportion of linoleic acid (C18:2 n6) was higher in equine and bovine compared to rat and caprine. Increase in lipid peroxidation in rat erythrocyte ghosts was maximal within 12 min of incubation, t-butyl hydroperoxide concentration dependent and was paralleled by a decrease in C18:2 n6, C20:4 n6 and C22:6 n3 and an increase in chemiluminescence formation. Polyunsaturated fatty acids (PUFAs) present in rat erythrocyte ghosts exhibit the highest sensitivity to oxidative damaged and their sensitivity increases as a power function of the number of double bonds per fatty acid molecule. Light emission in caprine, equine and bovine erythrocyte ghosts was very low, t-butyl hydroperoxide concentration-dependent but changes in fatty acid composition were not observed. The main conclusion of this work is that a low unsaturation degree of fatty acids in erythrocyte ghosts of caprine, equine and bovine prevent the lipid peroxidation on those membranes when they are incubated with t-butyl hydroperoxide.
本研究的目的是分析叔丁基过氧化氢诱导的大鼠、山羊、马和牛红细胞膜脂质过氧化、脂肪酸组成及化学发光强度的时间进程。大鼠红细胞膜中花生四烯酸(C20:4 n6)和二十二碳六烯酸(C22:6 n3)含量相对较高。从山羊、马和牛获得的天然红细胞膜的脂肪酸组成特点是油酸(C18:1 n9)含量高,可过氧化的多不饱和脂肪酸(C20:4 n6和C22:6 n3)含量低。与大鼠和山羊相比,马和牛的亚油酸(C18:2 n6)比例更高。大鼠红细胞膜脂质过氧化在孵育12分钟内达到最大值,与叔丁基过氧化氢浓度有关,同时伴随着C18:2 n6、C20:4 n6和C22:6 n3的减少以及化学发光的增加。大鼠红细胞膜中的多不饱和脂肪酸(PUFAs)对氧化损伤最敏感,其敏感性随每个脂肪酸分子双键数量的幂函数增加。山羊、马和牛红细胞膜的发光非常低,与叔丁基过氧化氢浓度有关,但未观察到脂肪酸组成的变化。这项工作的主要结论是,山羊、马和牛红细胞膜中脂肪酸的低不饱和度可防止其与叔丁基过氧化氢孵育时这些膜上的脂质过氧化。