大豆异黄酮和皂苷对糖尿病大鼠脂蛋白氧化修饰的抑制作用

脂质过氧化和低密度脂蛋白的氧化修饰在动脉硬化的发生中起着极其重要的作用.大豆异黄酮和皂甙具有多种药理作用.为研究大豆异黄酮和皂甙对糖尿病大鼠血浆及脂蛋白脂质过氧化水平的影响和低密度脂蛋白氧化易感性的变化,从大豆胚轴提取大豆异黄酮和皂甙,高效液相色谱法(HPLC)分析其有效成分.给糖尿病大鼠饲喂添加100 g kg-1大豆异黄酮和皂甙的饲料20周,观察血浆脂蛋白过氧化脂质(LPO)含量及氧化易感性的变化.结果表明,饲喂大豆异黄酮和皂甙后糖尿病大鼠血总LPO、LDL及HDL-LPO明显减少;在体外进行氧化修饰时,LDL氧化延滞时间明显延长.说明大豆异黄酮和皂甙可降低脂蛋白过氧化程度和增强LDL抗氧化修饰能力,因此能够起到防治糖尿病及其并发症的积极作用.     

大豆异黄酮甙元对结肠癌HT-29细胞增殖和凋亡的影响

大豆异黄酮通过促进肿瘤细胞凋亡可抑制多种肿瘤细胞的增殖.从大豆提取大豆异黄酮糖甙,再将其部分水解成其甙元,研究大豆异黄酮甙元抑制结肠癌细胞的增殖和促进其凋亡的作用.采用MTT比色法观察大豆异黄酮甙元对结肠癌HT-29细胞增殖的影响,采用TUNEL染色法检测其对HT-29细胞凋亡的影响,采用免疫细胞化学法检测凋亡相关蛋白bax、bcl-2和p53的表达.结果表明:大豆异黄酮甙元可在20～80 mg·L-1范围内时间和浓度依赖性地抑制结肠癌HT-29细胞增殖和诱导细胞凋亡.用40 mg·L-1大豆异黄酮甙元作用结肠癌HT-29细胞72 h时,细胞生长抑制率为(57.1±4.9)%,其对肿瘤细胞凋亡率为(20.9±2.1)%.免疫组化结果还显示,大豆异黄酮甙元可显著性增加HT-29细胞凋亡相关基因bax蛋白表达和降低bcl-2表达.提示,大豆异黄酮甙元可通过诱导结肠癌细胞凋亡发挥抗结肠癌作用.     

大豆异黄酮和皂甙对大鼠肝癌诱发初期肝脏氧化应激的干预作用

利用Solt-Faber法制备大鼠肝癌初期模型,同时以100 mg.kg-1大豆异黄酮和皂甙干预42 d。然后处死动物,制备肝匀浆及肝线粒体提取液。以比色法测定丙氨酸氨基转移酶(ALT)、门冬氨酸氨基转移酶(AST)、γ-谷酰胺转肽酶(γ-GT)、谷胱甘肽-S-转移酶(GST)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-PX)活性及丙二醛(MDA)含量。结果表明,大豆异黄酮和皂甙能降低肝癌发生初期大鼠肝脏ALT、AST、γ-GT和GST活性,升高肝脏及肝线粒体SOD、CAT、GSH-PX活性和降低MDA水平。提示,大豆异黄酮和皂甙具有减轻肝癌发生初期大鼠肝细胞损伤,降低其氧化应激的作用。此作用有助于预防肝癌的发生。     

大豆异黄酮和皂甙对H_(22)小鼠肝癌移植瘤的生长抑制及促细胞凋亡作用

为了探讨大豆异黄酮和皂甙对H_(22)小鼠肝癌移植瘤的生长抑制及促细胞凋亡作用,建立小鼠皮下H_(22)移植瘤模型,将其分为模型组、5-氟尿嘧啶组、大豆异黄酮组和大豆皂甙组。大豆异黄酮和大豆皂甙组分别按200 mg·kg~(-1)剂量每日灌胃给药,共10次;5-Fu组按25 mg·kg~(-1)剂量隔日腹腔注射给药,共5次。实验末期处死动物,计算抑瘤率、胸腺指数和脾脏指数,苏木素-伊红(HE)染色法观察肿瘤组织病理学变化,比色法检测肿瘤组织Caspase-3和Caspase-8相对活性以及血清还原型谷胱甘肽(GSH)含量、总抗氧化活力(T-AOC)和丙二醛(MDA)含量。结果表明:与模型组比较,大豆异黄酮和皂甙处理均能显著降低H_(22)小鼠肝癌移植瘤组织的瘤重,提高抑瘤率,其抑癌率分别为36.3%和34.8%。同时,大豆异黄酮和皂甙均显著升高荷瘤小鼠脾脏指数,增高肿瘤组织Caspase-3和Caspase-8相对活性,降低小鼠血清MDA水平,增高血清GSH和T-AOC水平。试验说明大豆异黄酮和皂甙对H_(22)小鼠肝癌移植瘤具有明显的抑瘤作用,其作用可能与其促细胞凋亡和抗氧化作用有关。     

大豆皂甙抗血浆脂质过氧化和红细胞保护作用的研究

用分光光度法测定大豆皂甙的总抗氧化能力(T-AOC)和抗活性氧能力(ROSSC),用八木变法测定血浆过氧化脂质(LOOn)含量,用硫代巴比妥酸(TBA)法测定血浆丙二醛(MDA)含量,用分光光度法测定红细胞溶血程度,以期研究大豆皂甙的体外抗脂质过氧化和红细胞保护作用.结果表明:大豆皂甙具有较强的体外总抗氧化能力和抗活性氧能力,可抑制血浆和红细胞膜脂质过氧化作用,减少红细胞溶血程度.说明大豆皂甙具有体外抗血浆脂质过氧化和红细胞保护作用.     

大豆异黄酮甙元抗脂质过氧化作用的研究

从大豆提取大豆异黄酮糖甙,再将其部分水解成其甙元,研究其体外抗氧化能力.用T-AOC方法测定化学模拟体系中的总抗氧化能力,用八木变法测定过氧化脂质(LOOH)含量,用硫代巴比妥酸(TBA)法测定丙二醛(MDA)含量,用分光光度法测定红细胞溶血和肝线粒体膨胀程度.结果表明:大豆异黄酮甙元的体外总抗氧化能力较强,可抑制血浆及肝组织脂质过氧化,减少红细胞溶血和减轻肝线粒体膨胀程度.说明大豆异黄酮甙元具有抗脂质过氧化作用.     

大豆异黄酮和皂甙对肝癌前病变大鼠血清标志酶及抗氧化活性的影响

采用改良Solt-Faber法建立大鼠肝癌前病变模型,以大豆异黄酮和皂甙饲喂大鼠42 d后,ELISA法测定血清肿瘤坏死因子-α(TNF-α),分光光度法测定γ-谷酰胺转肽酶(γ-GT)、丙氨酸氨基转移酶(ALT)、门冬氨酸氨基转移酶(AST)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-PX)活性及丙二醛(MDA)和一氧化氮(NO)含量。结果表明:大豆异黄酮和皂甙降低肝癌前病变大鼠血清γ-GT、ALT、AST活性,升高血清SOD、CAT、GSH-PX活性和降低MDA以及NO水平,但对血清TNF-α水平没有显著影响。表明大豆异黄酮和皂甙具有明显的抗化学致癌作用,其作用机制可能与增高抗氧化活性有关。     

大豆异黄酮及其衍生物对宫颈癌细胞增殖的影响

近年来的研究发现大豆异黄酮及其衍生物具有抗癌、抗氧化、抗突变等多种药理学作用.目前宫颈癌仍是严重威胁广大女性生命的恶性肿瘤之一,因此开发新的药物非常重要.本文对大豆异黄酮及其衍生物对宫颈癌细胞(Hela、CaSki、Me180、Siha)增殖方面的影响进行了综述,并对其作用途径进行了归纳总结,为研究开发宫颈癌药物提供了新思路.     

大豆异黄酮、皂甙、低聚糖一线三品加工产业设计

本文在查证大豆异黄酮、皂甙和低聚糖有关的技术资料和考察实地生产现场之后，根据国内目首的研发生产状态。设计出一个前处理、一条生产线、三个终端产品的加工产业生产设计，力求达到降低成本、降低能耗和降低原材料的目的。同时，对相关产品的质量、价格及市场做了简要说明，供生产营销人员参考。     

大豆胚轴体外诱导结肠癌细胞分化的研究

用免疫细胞化学法检测增殖细胞核抗原Ki-67和PCNA蛋白表达,分光光度法测定碱性磷酸酶(ALP)和乳酸脱氢酶(LDH)活性,ELISA法测定癌胚抗原(CEA)水平,研究了富含大豆异黄酮和皂甙的大豆胚轴提取物(SHE)对结肠癌细胞增殖和分化的影响。结果表明:富含大豆异黄酮和皂甙的大豆胚轴提取物可时间和浓度依赖性地降低结肠癌细胞Ki-67和PCNA表达,增加细胞ALP活性。CEA水平和LDH活性呈增高趋势,但差异不具有统计学意义。表明富含大豆异黄酮和皂甙的大豆胚轴可抑制结肠癌细胞增殖和诱导细胞分化,从而发挥抗结肠癌作用。     

Antiproliferative Effect of Amaranth Proteins and Peptides on HT-29 Human Colon Tumor Cell Line

Antiproliferative effect of Amaranthus mantegazzianus proteins and peptides released after simulated gastrointestinal digestion (DH% 37.8?±?3.8) was investigated on human colon cancer cell line HT-29. Inhibition of proliferation of HT-29 cells was exhibited after a 24 h treatment with different concentrations of amaranth protein isolate (API) and the peptides released after digestion (DGS), presenting IC₅₀ values of 1.35?±?0.12 and 0.30?±?0.07 mg soluble protein/mL, respectively. Lactate dehydrogenase assay indicated that both samples caused the loss of membrane integrity and cell lysis over HT-29 cells, and DAPI fluorescence microscopies evidenced typical apoptotic features. Moreover, Annexin V-FITC flow cytometry showed a significant increase of early apoptotic and late apoptotic/necrotic HT-29 cells compared to untreated ones, and caspase-3 assay confirmed the apoptosis induction with a 43.0?±?10.3 and 65.8?±?12.7% increase of caspase-3 activity produced by a 2 mg/mL treatment of API and DGS, respectively. In conclusion, amaranth peptides successfully released after simulated gastrointestinal digestion would exert a potential antiproliferative activity over HT-29 tumor cells. This effect was linked to the induction of cell necrosis and apoptosis, supporting the idea of using amaranth proteins as a potential food alternative ingredient for functional foods.

     

Methanolic Extracts of Uncaria rhynchophylla Induce Cytotoxicity and Apoptosis in HT-29 Human Colon Carcinoma Cells

In this paper, we report the anticancer activities of Uncaria rhynchophylla extracts, a Rubiaceae plant native to China. Traditionally, Uncaria rhynchophylla has been used in the prevention and treatment of neurotoxicity. However, the cytotoxic activity of Uncaria rhynchophylla against human colon carcinoma cells has not, until now, been elucidated. We found that the methanolic extract of Uncaria rhynchophylla (URE) have cytotoxic effects on HT-29 cells. The URE showed highly cytotoxic effects via the MTT reduction assay, LDH release assay, and colony formation assay. As expected, URE inhibited the growth of HT-29 cells in a dose-dependent manner. In particular, the methanolic URE of the 500 microg/ml showed 15.8% inhibition against growth of HT-29 cells. It induced characteristic apoptotic effects in HT-29 cells, including chromatin condensation and sharking occurring 24 h when the cells were treated at a concentration of the 500 microg/ml. The activation of caspase-3 and the specific proteolytic cleavage of poly (ADP-ribose) polymerase were detected over the course of apoptosis induction. These results indicate that URE contains bioactive materials with strong activity, and is a potential chemotherapeutic agent candidate against HT-29 human colon carcinoma cells.     

Geoditin A Induces Oxidative Stress and Apoptosis on Human Colon HT29 Cells

Geoditin A, an isomalabaricane triterpene isolated from the marine sponge Geodia japonica, has been demonstrated to dissipate mitochondrial membrane potential, activate caspase 3, decrease cytoplasmic proliferating cell nuclear antigen (PCNA), and induce apoptosis of leukemia cells, but the underlying mechanism remains unclear [1]. In this study, we found fragmentation of Golgi structure, suppression of transferrin receptor expression, production of oxidants, and DNA fragmentation in human colon cancer HT29 cells after treatment with geoditin A for 24 h. This apoptosis was not abrogated by chelation of intracellular iron with salicylaldehyde isonicotinoyl hydrazone (SIH), but suppressed by N-acetylcysteine (NAC), a thiol antioxidant and GSH precursor, indicating that the cytotoxic effect of geoditin A is likely mediated by a NAC-inhibitable oxidative stress. Our results provide a better understanding of the apoptotic properties and chemotherapeutical potential of this marine triterpene.     

NaCl诱导大豆根尖细胞凋亡的细胞学效应

以大豆种子为试材,NaC l溶液为诱导剂,分别对生长中的大豆根尖进行诱导,研究NaC l溶液处理浓度和处理时间对根尖细胞凋亡的影响,并对凋亡细胞进行形态学显微观察和基因组DNA分子凝胶电泳分析。结果表明:利用NaC l溶液处理根尖细胞,能够引起细胞凋亡,细胞凋亡频率与处理溶液浓度和处理时间有关;在细胞发生凋亡时,凋亡中的细胞形态和结构在不同时期表现各异。证明利用NaC l溶液作为诱导剂处理生长中的大豆根尖细胞,能够引起细胞凋亡;凋亡细胞的形态和结构发生变化,DNA发生降解。