刺参多糖清除活性氧保护线粒体的研究

本文采用酶解法(胃蛋白酶与胰蛋白酶)提取刺参多糖(Stichopus japonicus polysaccharides,SJP),以硫酸苯酚法测定多糖含量并研究其清除活性氧保护线粒体的作用机制。以Fe~(2+)-Vit C系统诱发肝线粒体脂质过氧化,以丙二醛(MDA)为指标测定SJP对脂质过氧化的影响;测定SJP的还原力及其对Fe~(2+)的螯合作用;以H_2O_2-Fe~(2+)体系为羟自由基(·OH)生成系统,测定SJP清除·OH的能力;用滴定法测定SJP清除过氧化氢(H_2O_2)的能力;用氮蓝四唑(NBT)法测定SJP清除超氧阴离子(O_2·~-)的能力。研究表明:SJP可抑制MDA生成;SJP具有一定的还原力和较弱的Fe~(2+)螯合作用;另外,SJP能在一定浓度范围内明显清除·OH、H_2O_2和O_2·~-。SJP能通过抗氧化、清除活性氧(ROS)来保护线粒体,具有保护机体的功效,这是SJP保护线粒体的可能机制。

Study on the Mitochondrial Protection of Stichopus japonicus Polysaccharides by Scavenging Reactive Oxygen Species

Stichopus japonicus polysaccharides (SJP) were extracted by enzymatic hydrolysis (pepsin and trypsin), polysaccharide content was determined by phenol/sulfate method and the possible mechanism of scavenging reactive oxygen species (ROS) for SJP to protect mitochondria were investigated in this study. The hepatic mitochondrial lipid peroxidation was induced by Fe2+-Vit C system, malondialdehyde (MDA) was used as an index to determine the effect of SJP on lipid peroxidation; effects of SJP on the reducing power and Fe2+ chelating were measured; the scavenging activity of SJP on the hydroxyl radical (?OH) which was produced by H2O2-Fe2+ system was measured; the method of titration and the method of nitrogen blue tetrazolium (NBT) were used to measure the scavenging activity of SJP on the hydrogen peroxide (H2O2) and superoxide anion (O2??), respectively. The results showed that SJP could inhibit the production of MDA; SJP had a certain reducing power and weaker Fe2+ chelating activity. In addition, SJP could scavenge ?OH, H2O2 and O2?? within a certain concentration range. SJP could protect mitochondria through anti-oxidation and scavenging reactive oxygen species (ROS), which had the effect of protecting the body. This was the possible mechanism of SJP to protect mitochondria.