氧化和抗氧化指标在大鼠高脂饮食所致脂肪肝中的动态变化

1、氧化和抗氧化指标在大鼠高脂饮食所致脂肪肝中的动态变化     【摘要】  目的 探讨氧应激和脂质过氧化在高脂饮食所致脂肪性肝炎形成中的作用。方法 雄性SD大鼠 30只随机分为3组，每组10只。正常组普通饲料喂养；模型、组喂高脂饲料；12周末处死正常组、模型组大鼠；模型组大鼠继续喂养至16周末处死，测定血清转氨酶（ALT、AST），全血谷胱甘肽过氧化物酶（GSHPX），肝匀浆丙二醛（MDA）含量，超氧化物歧化酶（SOD）活性，总抗氧化能力（TAOC），一氧化氮（NO），诱导型一氧化氮合酶（iNOS），谷胱甘肽（GSH）水平，观察肝组织学改变。结果

2、 模型组大鼠12周出现单纯性脂肪肝，16周发展为脂肪性肝炎。与正常组比，模型组大鼠肝组织脂质过氧化产物MDA含量明显增多，而抗氧化物SOD，GSH，GSHPX含量明显降低，且肝脏的脂肪变性严重程度随着高脂饮食喂养的时间延长而加剧。结论 氧应激和脂质过氧化在肝组织脂肪变性后炎症的过程中发挥重要作用。 【关键词】  氧应激脂质过氧化非酒精性脂肪性肝炎Development Changes of Oxidative and Antioxidative Indexes in Establishment of Steatohepatitis in Rats Fed by Highfat Die

3、tsPeng Haiying, Yu Hongbo, Zuo Zhong (Dalian Sanatorium of Shenyang Military Region, Dalian 116013, China; PLA No.210 Hospital, Dalian 116021, China)Abstract： Objective  To explore the role of oxygen stress and lipid peroxidation in the establishment of steatohepatitis in rats fed by highf

4、at diets. Methods  Thirty male Sprague Dawley rats were assigned into three groups (n=10) at random. The rats fed by normal foods served as controls. The rats in model groups (, ) were fed with high-fat diets. The animals in control group and model I group were killed at the end of the 12th wee

5、k, and the ones left were killed at the end of the 16th week. Blood samples were collected for the detection of serum aspartate transaminase (AST), alanine aminotransferase (ALT) and glutathione peroxidase (GSHPX), and liver tissues were obtained for the detection of malondialdehyde (MDA) contents,

6、superoxide dismutase (SOD) activity, total antioxidative capacity (TAOC), and nitric oxide (NO), inducible nitric oxide synthase (iNOS) and glutathione (GSH) levels. The histological changes were observed under light microscope. Results  Pure fatty liver was formed in the model rats after in th

7、e 12th week, and fatty hepatitis was established in the 16th week. In comparison with those of normal rats, the contents of MDA were increased (P<0.01) but antioxide SOD, GSH, GSHPX contents were decreased significantly (P<0.05, or P<0.01). The severity of hepatic fatty degeneration aggrava

8、ted with the prolonging of the highfat diets taking duration.  Conclusion  Oxidative stress and lipid peroxidation may play an important role in the formation of liver inflammation cell infiltration.Key  words： oxygen stress; lipid peroxidation; nonalcoholic steatohepatitis研究认为氧应激和脂质过

9、氧化在非酒精性脂肪性肝炎(nonalcoholic  steatohepatitis，NASH)发病中占有重要地位13。我们通过高脂饮食建立NASH大鼠模型，动态检测氧化和抗氧化指标观察实验性NASH肝组织的氧化损伤。1  材料和方法1.1  材料  雄性SD大鼠 30只，体重（150±10）g，购自大连医科大学实验动物中心。胆固醇购自上海伯奥生物工程公司，猪油自备。超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、诱导型一氧化氮合酶(iNOS)、总抗氧化能力(TAOC)、谷胱甘肽过氧化物酶(GSHPX)、还原型谷胱甘肽 (GSH)

10、等试剂盒购自南京建成生物工程公司。1.2  方法  大鼠普通饲料喂养1周后，随机分为3组(每组10只)。正常组普通饲料喂养；模型、组喂高脂饲料(880 g/kg普通饲料+100 g/kg 猪油+20 g/kg 胆固醇)。各组大鼠自由进食、进水，分笼(每笼5只)饲养于（20±2）、明暗各12 h 的动物实验室内。12周末处死正常组、模型组大鼠；模型组大鼠继续喂养至16周末处死。方法为禁食12 h，乙醚麻醉，下腔静脉采血后处死，迅速取出肝脏，按常规制备血清、肝匀浆、肝组织石蜡切片标本，肝组织于-70 低温保存。（1）采用全自动生化分析仪测定血清ALT、AST，全血GS

11、HPX (DTNB直接法)；（2）肝匀浆测定MDA含量(改进后的硫代巴比妥酸荧光法)，SOD活性 (改良的盐酸羟胺法)，TAOC、NO、iNOS、GSH(按试剂盒说明操作)；（3）肝脏病理学检查，光镜下评估脂肪变性程度和炎症活动度计分45。1.3  统计学处理  计量资料以均值±标准差（±s）表示，各组间实验数据采用两样本均数的t检验；等级资料采用秩和检验。2  结果2.1  血清ALT、AST及全血GSHPX变化  与正常组比较，模型，组ALT，AST显著增高(P0.01)，GSHPX显著下降(P0.01)，详见表1。表1  各组大鼠血清生化指标（略）与正常组比较，P0.012.2  肝MDA、NO、iNOS、SOD、TAOC及GSH变化  与正常组比较，模型组MDA显著增高，SOD、GSH下降明显(P0.05)；模型组MDA、iNOS、NO显著增高(P0.01，P0.05)；模型组SOD、TAOC、GSH增高(P0.01)，详见表2。表2  各组大鼠肝匀浆生化指标（略）与正