【作者】 杨慧；

【导师】 杨军；

【作者基本信息】 中国医科大学 ， 儿少卫生与妇幼保健学， 2004， 硕士

【摘要】 实验目的 衰老是生命周期中随时间进展而表现出机体功能不断恶化直到死亡的复杂动态变化过程。衰老的自由基学说认为，自由基及其诱导的脂质过氧化对生物膜的损害作用是衰老发生的主要原因之一。年龄的增加使机体自由基的产生过多而清除能力下降，机体内物质代谢紊乱、酶活性发生改变。细胞凋亡可能也是这种失衡的结局。 植物化学物具有较强的抗氧化作用，能有效地清除氧自由基，可以延缓衰老的发生发展。其中研究较多的是β-胡萝卜素和番茄红素，它们具有抗氧化、抑制突变、降低核酸损伤、预防衰老和预防癌症等多种功能。增加富含类胡萝卜素蔬菜的摄入可以使机体血浆和组织的β-胡萝卜素、番茄红素等类胡萝卜素浓度升高，从而提高抗氧化水平。 单一抗氧化剂的作用与果蔬整体作用的效果不同。本研究采用以富含类胡萝卜素为主的两种蔬菜——胡萝卜和番茄，以自然进食的方式直接干预D-半乳糖致大鼠拟衰老模型，研究其延缓大鼠衰老的作用，为进一步进行人群干预试验提供基础研究的数据。 实验方法 1．胡萝卜和番茄的处理 选用非棚栽成熟胡萝卜、番茄，去掉非可食部分，洗净，用去离子水冲洗3次，避光晾干，称重，破碎后加5％植物油混匀，0.05MPa高压10分钟，冷却后于0-4℃避光冷藏备用。 2．测定指标及方法 2．1胡萝卜和番茄的实际摄入量 每天早晨称量前一晚喂饲胡萝卜或番茄的剩余量计算实际摄入量。 2．2外观特征 随时观察大鼠外观变化，如皮毛情况、活动及精神状态等，每周称一次体重。 2．3丙二醛(MDA)含量 硫代巴比妥酸比色法。 2.4超氧化物歧化酶(SOD)活性亚硝酸盐法。 2.5谷耽甘肤过氧化物酶(GSH一入)活性5，5’一二硫代2一硝基苯甲酸显色法。 2 .6细胞凋亡率流式细胞仪碘化丙陡染色法。 3.动物喂养及干预处理 6周龄健康雄性Wistar大鼠适应性喂养1周后随机分成4组(n二8):对照组(A组)、衰老组(B组)、胡萝卜干预组(C组)、番茄干预组(D组)，自由进食饮水。每天A组颈背部皮下注射生理盐水looml/纯.bw，B组、c组、D组颈背部皮下注射D一半乳糖loom岁纯.bw，同时C组加喂胡萝卜159，D组加喂番茄159，进行26周的干预试验。 4.统计分析处理 用SPSS软件对实验数据进行方差分析。实验结果 1.胡萝卜和番茄的实际摄人量 胡萝卜组每只大鼠平均每天实际摄人胡萝卜13.89，番茄组每只大鼠平均每天实际摄人番茄13·79。 2.大鼠外观特征 衰老组大鼠比其它组大鼠毛色枯黄、行动迟缓、精神不振;第6一13周衰老组、胡萝卜组和番茄组大鼠体重明显高于对照组(P<0.05)。 3.各组大鼠肝脏、肾脏、脑及血MDA含量 实验10周末B组大鼠血清MDA含量明显高于A组、C组和D组(P<0 .05);实验26周末，B组大鼠肝脏中MDA含量显著高于A组、C组和D组(P<0.01，P<0.05，P<0.05)，肾脏中MDA含量也显著高于A组、C组和D组(P<0.01)，A组、C组和D组之间各脏器MDA含量没有统计学差异(P>0 .05)。 4.各组大鼠肝脏、肾脏、脑及血soD、CSH一Px活性 B组大鼠肝脏SOD活性比A组明显降低(P<0.05)，脑soD活性明显低于A组和D组(P<0.05);脑GsH一h活性明显低于A，组和C组(P<0 .05)。A组、C组和D组之间各脏器soD及CSH一Px活性均没有统计学差异(P>0.05)。 5.各组大鼠脾细胞凋亡率 B组大鼠脾细胞凋亡率明显高于A组、C组和D组(P<0 .05)，A组脾细胞凋亡率明显低于C组和D组(P<0.05)。结论 1.本实验所用胡萝卜、番茄可抑制D一半乳糖致大鼠拟衰老模型肝脏、肾脏MDA的形成。 2.本实验所用胡萝卜、番茄可分别改善D一半乳糖致大鼠拟衰老模型脑CSH一h及soD活性的降低。 3.本实验所用胡萝卜、番茄降低了D一半乳糖致大鼠拟衰老模型的脾细胞凋亡。更多还原

【Abstract】 SubjectAging is a complex development process in life cycle, during which the functions of the body are deteriorated until its death. The free radical theory of aging indicates that the effect of membrane damage produced by free radicals and lipids peroxidation is one of the major reasons of aging. With the age increasing , excessive free radicals production and lower ability of elimination alternates the metabolism of body and the action of enzymes. Apoptosis may be the result of the imbalance.Phytochemicals have a strong capability of antioxidation. They can eliminate free radicals effectively, thus stave off occurring and development of aging. β - carotene and lycopen, which were studied more often, have many functions, such as antioxidation, restraining mutation, depressing the damage of nucleic acid, preventing aging and cancer. Increasing of the intake of carotenoid - rich vegetables and fruits may enhance the concentrations of carotenoid, such as |3 -carotene and lycopen, in blood and organism, so the ability of antioxidation may be advanced.There are different impacts between single antioxdant and whole vegetables and fruits. We studied the aging preventing effect in rats which were aging produced by D - galactose, using two carotenoid - rich vegetables, carrot and tomato , treated directly with feeding free. This will provide the base data for further study in human body.Materials and Methods1. Treatment of carrot and tomatoNatural grown tomato and carrot were selected as experimental materials, left the parts of availability which were washed three times with water without i-ons. After weighted up, the homogenate of carrot and tomato with 5% plant oil in cans were put in the condition of high pressure at 0. 05MPa for 10 minuets, then cooled and stored at 0 -4 against light.2. Indexes analysis2.1 The actual intake of carrot and tomato: Weighting the carrot or tomato left in the next morning to calculate the actual intake.2.2 The character of aspect: Observing the changes of aspect at any moment and weighted up the rats every week.2.3 The concentration of MDA; With the method TBA colorimetry;2.4 The activity of SOD; With the method nitrite reduction;2.5 The activity of GSH -Px: With DTNB colorimetry;2.6 Ratio of apoptosis of spleenocytes: Analyzed by PCM using propidium staining method.3. Animals feeding and treatment32 six - week health male Wistar rats were fed for one week, fallen into four groups in random( n = 8 ) : normal group ( group A) , aging group ( group B) , carrot group ( group C) and tomato group ( group D). The rats ate and drank freely. Every day, rats of group A were subcutaneous injected with saline 100ml/kg. bw at dorsal of neck; rats of group B, C and D were subcutaneous injected with D - galatose 100mg/kg. bw, at the same time, rats of group C were fed with carrot 15g, and rats of group D were fed with tomato 15g. At the 25th weekend of the experiment, we stopped the injection of saline in the group A and of D - galatose in the other groups.4. Statistics analysisAll data were analyzed with ANVON by SPSS statistic software.its1. Actual intake of carrot and tomatoEvery day, the average actual intake of carrot for every rat in carrot groupwas 13. 8g, the average actual intake of tomato for every rat in tomato group was 13.7g.2. The characters of aspectCompared with the other rats, the rats of aging group were scorcher in hair, slower in action and cachexia. From the 6th week to the 13th, the weight of rats in notmal group was lower in evidence than those of the other rats in aging group, carrot group and tomato group (P <0.05).3. The concentration of MDAAt the 10th weekend, the concentration of MDA in the serum of rats in aging group was increased obviously than those of the other rats in normal group, carrot group and tomato group (P <0. 05). At the end of the study (the 26th weekend) , the increased concentration of MDA in the liver of rats in aging group was more significant than those in the nor更多还原