Choi J H, Cha B K, Rhee S J
Department of Food Science and Nutrition, Catholic University of Teagu-Hyosung, Kyungsan-si, Kyungbuk, Korea.
J Nutr Sci Vitaminol (Tokyo). 1998 Oct;44(5):673-83. doi: 10.3177/jnsv.44.673.
In this study, male Sprague-Dawley rats weighing 70 +/- 5 g were divided into a control (normal) group and three different diabetes mellitus (DM) groups that were supplemented with catechin-free (DM-0C), 0.5% catechin dietary (DM-0.5C), and 1% catechin (DM-1.0C). The animals were maintained on an experimental diet for four weeks. At this point, they were injected with streptozotocin (STZ) to induce diabetes, and they were sacrificed on the 6th day to determine the activities of phospholipase A2 (PLA2) and the changes of phospholipid species by catechin supplementation. In liver tissues, no significant differences were found between the PC hydrolysis of a normal group and a diabetic group; however, PE hydrolysis of the DM-0C, DM-0.5C, and DM-1.0C groups increased by 68.9%, 34.01%, and 26.9%, respectively, compared with the normal group. Although the PLA2 activity of the DM-0C group in the liver tissues increased 91% compared with the normal group, the PLA2 activity of DM-0.5C and DM-1.0C, which were fed catechin, increased 50% and 56%, respectively, compared with the normal group. In the liver tissues, peroxide values of the DM-0C, the DM-0.5C, and the DM-1.0C groups were increased 109%, 32.8%, and 46.7%, respectively, compared with the normal group. Based on these results for STZ-induced diabetic rats, lipid peroxidation seems to be accelerated specifically with the increased PLA2 activities. Thus if antioxidants like catechin were supplementation, the activity of PLA2 and PE hydrolysis can be altered and the accumulation of lipid peroxide would be decreased. Therefore we concluded that the antioxidant catechin for diabetic animals can significantly reduce PLA2 activities and lipid peroxide formation.
在本研究中，将体重70±5克的雄性Sprague-Dawley大鼠分为对照组（正常组）和三个不同的糖尿病（DM）组，分别为不含儿茶素的糖尿病组（DM-0C）、含0.5%儿茶素饮食的糖尿病组（DM-0.5C）和含1%儿茶素的糖尿病组（DM-1.0C）。动物维持实验饮食四周。此时，给它们注射链脲佐菌素（STZ）以诱导糖尿病，并在第6天处死，以测定磷脂酶A2（PLA2）的活性以及通过补充儿茶素引起的磷脂种类变化。在肝脏组织中，正常组和糖尿病组的磷脂酰胆碱（PC）水解之间未发现显著差异；然而，与正常组相比，DM-0C、DM-0.5C和DM-1.0C组的磷脂酰乙醇胺（PE）水解分别增加了68.9%、34.01%和26.9%。虽然肝脏组织中DM-0C组的PLA2活性比正常组增加了91%，但喂食儿茶素的DM-0.5C和DM-1.0C组的PLA2活性与正常组相比分别增加了50%和56%。在肝脏组织中，与正常组相比，DM-0C、DM-0.5C和DM-!0C组的过氧化值分别增加了109%、32.8%和46.7%。基于这些STZ诱导的糖尿病大鼠的结果来看，脂质过氧化似乎随着PLA2活性的增加而加速。因此，如果补充儿茶素等抗氧化剂，PLA?的活性和PE水解可以改变，脂质过氧化物的积累也会减少。所以我们得出结论，糖尿病动物使用抗氧化剂儿茶素可显著降低PLA2活性和脂质过氧化物的形成。
