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81.
82.
目的:研究大豆异黄酮对去卵巢小鼠认知功能的影响并探讨其机制。方法:45只健康雌性昆明种小鼠按体重随机均分为5组,A组为对照组(假手术组),B组为去卵巢模型组(OVX),C组为OVX+大豆异黄酮低剂量组,D组为OVX+大豆异黄酮中剂量组,E组为OVX+大豆异黄酮高剂量组。试验期为60 d。结果:B组小鼠到达水迷宫终点时间明显长于D组和E组(P<0.05);跳台记忆试验B组小鼠平台潜伏期短于D组, 且错误次数高于A,C,D,E组(P<0.05)。A,C,D,E组小鼠血清SOD活力、脑组织Na+K+-ATP酶活力均高于B组,血清MDA水平均低于B组(P<0.05);Ca2+ Mg2+-ATP活力A,D组高于B组,E组小鼠脑组织中AchE活力明显高于B,C,D,组(P<0.05),单胺氧化酶活力B组高于D组(P<0.05)。结论:持续口服大豆异黄酮可以明显改善去卵巢小鼠的认知功能。 相似文献
83.
Memory performance, brain excitatory amino acid and acetylcholinesterase activity of chronically aluminum (Al) exposed mice in response to soy isoflavones (SI) treatment was investigated in the study. Forty eight mice were allotted randomly into a control group, an Al exposed group (100 mg/kg Al) and an Al exposed group treated with SI (100 mg/kg Al + 60 mg/kg SI) for 60 days. Chronic Al exposure significantly impaired long memory performance in mice as assessed using a passive avoidance task test (χ(2) analysis, p < 0.05). Interestingly, SI treatment markedly improved the memory performance score in the Al exposed mice. This improvement was associated with a total reversal of Al-induced increases in acetylcholinesterase activity in the cerebral cortex and hippocampus of mice. The Al exposure also led to significant decreases in brain levels of aspartic and glutamic acids, two excitatory amino acid neurotransmitters; whereas SI treatment partially reversed the decreased aspartic and glutamic acid contents in the hippocampus. The results suggest that SI can improve long memory performance in the Al exposed mice, possibly by modulating the metabolism of brain acetylcholine and amino acid neurotransmitters. 相似文献
84.
大豆异黄酮对C6胶质瘤细胞侵袭力的影响 总被引:1,自引:0,他引:1
目的:观察大豆异黄酮(soybean isoflavones,SI)对大鼠C6胶质瘤细胞侵袭力的影响。方法:C6胶质瘤细胞分为对照组和大豆异黄酮(20、40、80mg/kg)4组,分别采用Boyden小室法检测细胞侵袭力,realtime PCR、免疫组织化学方法检C6胶质瘤细胞中MMP-2、MMP-9mRNA和蛋白含量。结果:大豆异黄酮低剂量组即能明显降低大鼠C6细胞侵袭力,MMP-2、MMP-9mRNA和蛋白含量。结论:大豆异黄酮能降低大鼠C6细胞侵袭力。 相似文献
85.
C. P. Teixeira R. Florencio-Silva G. R. S. Sasso A. A. F. Carbonel R. S. Simões M. J. Simões 《Gynecological endocrinology》2019,35(7):586-590
Ovarian aging is characterized by declines in follicular reserve and oocyte quality due, in part, to increased oxidative stress and apoptosis. Soy isoflavones (ISOs) have been shown to improve ovarian lifespan by acting as antioxidant and antiapoptotic agents. We aimed at evaluating whether ISOs could modulate oxidative stress and reduce apoptosis and improve ovarian follicle survival in middle-aged female rats. Twelve ovary-intact female Wistar rats (12-month-old) were divided into groups: control (CTRL) and ISO, daily treated by gavage with vehicle or soy-ISO extract (150?mg/kg b.w), respectively. After 8?weeks, rats were euthanized and their ovaries removed for histomorphometric (% follicles) and apoptosis (cleaved-caspase-3/BCL2 immunostaining) evaluations, or subjected to biochemical assays to survey reactive oxygen species (ROS) and lipid peroxidation levels and total antioxidant capacity (TAC). The frequency of atretic follicles and number of cleaved-caspase-3-positive cells, as well as the ROS and lipid peroxidation levels, were significantly lower in ISO group compared to CTRL. A significantly higher number of BCL2-positive cells and TAC levels were also observed in ISO group. In conclusion, soy ISOs could decrease follicular atresia, apoptosis and oxidative stress, as well as increase the TAC in ovaries of female rats. 相似文献
86.
大豆异黄酮诱导人胃癌细胞株SGC-7901凋亡的研究 总被引:6,自引:0,他引:6
目的:探讨大豆异黄酮对体外培养的人胃癌细胞SGC-7901生长的抑制和诱导细胞凋亡的作用.方法:用MTT法检测药物效应,透射电镜及流式细胞仪观察大豆异黄酮处理SGC-7901细胞后细胞周期和细胞凋亡.结果:(1)MTT法证实大豆异黄酮对SGC-7901细胞生长有抑制作用,并呈剂量-效应关系.(2)流式细胞仪分析大豆异黄酮处理SGC-7901细胞后细胞滞留于G2/M期,并可见凋亡峰.(3)透射电镜可见SGC-7901细胞出现典型的凋亡细胞形态学改变.结论:大豆异黄酮对人胃癌细胞SGC-7901有抑制作用,抑制作用与诱导胃癌细胞凋亡、阻抑细胞周期进程有关,诱导胃癌细胞凋亡、阻抑细胞周期进程是大豆异黄酮抗胃癌作用的机制之一. 相似文献
87.
Genistein, an isoflavone, has been demonstrated to promote the health of human beings by reducing the incidence of specific chronic diseases, namely, cancer and atherosclerosis. The present investigation explores a novel method of extraction of genistein from soy source which consists of a bioconversion reaction using fermentation by microorganism namely Streptomyces roseolus NRRL B-5424. In situ bioconversion of genistein glycoside to aglycone was carried out by the microbe. Such methodology has not been reported hitherto. Optimization of upstream and downstream parameters was done for maximum extraction of genistein. Genistein was isolated in a powder form by column chromatography and preparative thin layer chromatography and was characterized using massspectrometry, nuclear magnetic resonance and infrared spectroscopy and its purity determined using high performance liquid chromatography. Genistein was extracted with 91.04% purity and extraction efficiency was 67.01%. 相似文献
88.
加压溶剂法提取槐角总异黄酮的研究 总被引:1,自引:1,他引:0
目的优化加压溶剂法提取槐角总异黄酮的最佳工艺参数。方法采用紫外分光光度法测定总异黄酮,以总异黄酮得率为指标,利用正交试验进行优选,考察提取时间、提取温度、提取压力、乙醇体积分数和固液比对提取效果的影响,并纯化得到槐角异黄酮和槐角多糖粗提物。结果最佳工艺条件为提取压力900 kPa、提取温度110℃、提取时间10 min、乙醇体积分数50%、固液比1∶12.5。此时槐角总异黄酮得率为28.4%,槐角异黄酮粗提物得率为32.6%、异黄酮质量分数为48.5%。结论加压溶剂法是一种省时、节能、高效、环保的中药有效成分提取方法,具有广阔的应用前景。 相似文献
89.
目的:考察壳聚糖絮凝沉降法对葛根芩连汤中黄酮及生物碱类成分的影响。方法:以葛根素、黄芩苷、盐酸小檗碱、浸膏率作为考察指标,采用正交试验法研究药液浓缩程度、壳聚糖用量、pH对壳聚糖絮凝沉降法精制葛根芩连汤中黄酮和生物碱类成分的影响,并与乙醇沉淀法、离心沉降法及滤过法进行比较。结果:壳聚糖絮凝沉淀法的最佳条件为药液质量浓度0.78 g.mL-1,壳聚糖加入量10%、药液pH 6,与不同沉淀方法比较,壳聚糖的沉淀效果最佳。结论:壳聚糖可有效保留药液中有效成分,降低浸膏率,同时改变药液中成分的组成比例,因此选用此方法时需慎重。 相似文献
90.
大豆异黄酮对脑缺血再灌注大鼠海马神经再生的影响 总被引:1,自引:0,他引:1
目的?观察大豆异黄酮对脑缺血再灌注大鼠海马神经再生的影响。方法?线栓法建立大鼠脑缺血再灌注模型,分别给予大豆异黄酮(SI)、7硝基吲哚(7NI)或联合给药(SI+7NI),BrdU免疫荧光法标记新生海马神经细胞,免疫组化法检测海马区ONOO-的反应产物硝基酪氨酸(NT)。结果?SI组、7NI组和SI+7NI组大鼠海马区BrdU+细胞数增加更显著,NT的数量明显减少(P<0.05,P<0.01)。结论?长期给予大豆异黄酮可以使脑缺血再灌注时病理性的ONOO-生成减少,并促进脑缺血组织的海马神经再生,这对脑缺血损伤有潜在的应用价值。 相似文献