桦木酸对环磷酰胺致小鼠肠道氧化损伤的影响

摘要

The experiment was conducted to evaluate the effect of betulinic acid (BA) on intestinal oxidative damage induced by cyclophosphamide (Cy) in mice.Male Kunming mice were randomly divided into 5 groups:control group (NC),Cy group,0.5 mg · kg-1 BA group,5.0 mg · kg-1 BA group and 50.0 mg · kg-1 BA group.The control and Cy group were administered orally with 1％ starch and the other groups were administered orally with different doses of BA (0.5,5.0,and 50.0 mg · kg-1) daily for 14 days.The model of intestinal oxidative damage was set up in mice induced by Cy at the dosage of 50 mg · kg-1 bw for 2 days after last administration of BA.The liver,spleen and thymus index of mice were measured,the activity of secretory immunoglobulin a (SIgA) in intestinal mucosa and the levels of the superoxide dismutase (SOD),malondialdehyde (MDA) and glutathione (GSH) in intestine and serum were determined.BA pretreatment relieved atrophy of thymus,spleen and liver,inhibited the decline of SIgA activity in intestinal mucosa induced by Cy.Pretreatment with BA reduced the contents of GSH and MDA in small intestine and serum induced by Cy,but had no effect on SOD activity.BA could improve intestinal lipid peroxidation and increase the secretion of SIgA in the intestine mucosa and shows preventive protection of Intestinal oxidative damage induced by Cy.%旨在研究桦木酸(betulinic acid,BA)对环磷酰胺(cyclophosphamide,Cy)致小鼠肠道氧化损伤的影响.将健康雄性昆明小鼠随机分为5组:对照(NC)组、Cy组、0.5 mg·kg-1 BA组、5.0 mg·kg-1 BA组、50.0 mg·kg-1BA组.NC组和Cy组灌服1％的可溶性淀粉,其余各组按不同剂量的BA混悬于可溶性淀粉中灌服,1次·d-1,连续14 d后,除NC组注射生理盐水外,其余4组均连续2d腹腔注射Cy(50 mg·kg-1)诱导肠氧化损伤模型.检测肝、脾和胸腺指数,肠黏膜中分泌型免疫球蛋白α(secretory immunoglobulin a,SIgA)水平,血清和肠道中超氧化物歧化酶(superoxide dismutase,SOD)活性,还原型谷胱甘肽(glutathione,GSH)和丙二醛(malondialdehyde,MDA)含量变化.结果表明:BA预处理后,能缓解Cy引起的肝、脾和胸腺指数下降,促进肠黏膜SIgA的分泌,不同程度缓解了Cy引起小鼠血清和小肠MDA、GSH含量的升高,以中剂量效果最佳,BA对SOD活力无影响.结果表明BA能改善Cy引起的小鼠肠道脂质过氧化及提高肠道中SIgA的分泌,对Cy诱导的肠道氧化损伤有预防性的保护作用.