金雀异黄素对低密度脂蛋白氧化修饰及氧化型低密度脂蛋白诱导的血管内皮细胞c-myc mRNA表达的抑制作用

为探讨大豆异黄酮（金雀异黄素和大豆甙元）在防止低密度脂蛋白氧化方面的作用以及对氧化型低密度脂蛋白诱导的血管内皮细胞原癌基因c-myc表达的影响，采用Cu^2 介导的低密度脂蛋白体外氧化方法，通过测定硫代巴比妥酸反应物质生成和琼脂糖电泳迁移率的变化来观察大豆异黄酮对低密度脂蛋白氧化修饰的抑制作用；采用Northern blot杂交技术，分析氧化型低密度脂蛋白对人脐静脉内皮细胞c-myc原癌基因mRNA表达的作用以及金雀异黄素对此表达的影响。结果发现，金雀异黄素能够浓度依赖性减少硫代巴比妥酸反应物质生成，降低低密度脂蛋白的相对电泳迁移率（P＜0．05）；氧化型低密度脂蛋白（200mg/L)刺激人脐静脉内皮细胞c-myc mRNA在1－2h内表达增高，表达量为对照水平的3倍，4h回到对照水平以下；金雀异黄素（100μmol/L）能有效抑制氧化型低密度脂蛋白诱导的c-myc mRNA表达增高。以上结果提示，金雀异黄素不仅能防止低密度脂蛋白发生氧化，而且能够抑制氧化型低密度脂蛋白诱导的人脐静脉内皮细胞c-myc mRNA表过增高。     

大豆苷及大豆苷元溶解吸收特性差异比较及相互作用研究

目的：考察大豆苷和大豆苷元的溶解吸收特性及两者共存条件下在溶解和吸收方面的相互影响。方法采用溶解度实验技术测定大豆苷和大豆苷元的平衡溶解度;采用大鼠在体单向肠灌流方法研究大豆苷元和大豆苷肠渗透性相互作用。结果在pH＝7.4的K-R试液中,大豆苷的溶解度约为大豆苷元的6倍,两者共存时溶解度均有所增强。大豆苷元在大鼠肠道内的吸收系数约为大豆苷的3倍,大豆苷对大豆苷元的吸收有显著性增强作用,但大豆苷元对大豆苷的吸收有抑制作用。结论大豆苷元的溶解度低于大豆苷,渗透性高于大豆苷。两者合用后大豆苷元的溶解度和渗透性均明显增强,大豆苷的溶解度增强不显著,且渗透性显著降低。     

大豆苷元对人非小细胞肺癌A549、H1299细胞增殖、迁移能力的影响及机制

目的探究大豆苷元(daidzein,Daid)对非小细胞性肺癌细胞株A549和H1299增殖、迁移能力的影响及可能机制。方法以A549和H1299为研究对象,CCK-8法检测Daid(0,5,10,25,50,100,200μmol·L^-1)抑制A549和H1299两种细胞的增殖情况。划痕和Transwell小室实验检测Daid对肺癌细胞迁移和侵袭能力的影响。Western blot检测Cleaved Caspase-3和LC3Ⅱ/Ⅰ等的蛋白表达。结果与对照组相比,Daid在体外可明显抑制肺癌细胞的增殖,且抑制作用呈浓度依赖关系。Daid(100μmol·L^-1)可明显降低人肺癌细胞A549和H1299的迁移侵袭能力。Western blot结果显示,Daid(100μmol·L^-1)预处理后,两种肺癌细胞的Cleaved Caspase-3及LC3Ⅱ/Ⅰ表达升高。结论Daid可抑制人非小细胞肺癌A549和H1299细胞的增殖,使上述细胞的迁移侵袭能力明显下降,其机制可能与Daid诱导细胞凋亡及自噬有关。     

Endocrine disrupting effects in rats perinatally exposed to a dietary relevant mixture of phytoestrogens

Dietary phytoestrogens may prevent certain human diseases, but endocrine activity has been reported in animal studies. Sprague-Dawley rats were exposed perinatally to a 1-, 10- or 100-fold “high human dietary intake” mixture of 12 phytoestrogens consisting of mainly the lignan secoisolarici resinol and the isoflavones genistein and daidzein.This mixture induced persistent adverse effects, as adult male mammary glands showed hypertrophic growth. A reduced anogenital distance in newborn males indicated an anti-androgenic mode of action. Testosterone levels, testis and prostate weights, and expression of selected genes in testis and prostate were unaffected. Decreased serum estradiol was seen in genistein-exposed dams. This study indicated adverse effects at high intake levels in rats, but does not provide evidence for risk of phytoestrogen-mediated endocrine disruption at normal human dietary consumption levels. Further studies are warranted to increase the knowledge upon which risk assessment on dietary phytoestrogen exposure during pregnancy and infancy is based.     

葛根黄豆甙元的溶解度和电离常数的测定

本文报道了葛根黄豆甙元在不同pH溶液中的溶解度和它的电离常数。     

Effects of dietary equol administration on ovariectomy induced bone loss in Sprague-Dawley rats

Oestrogen deficiency leads to a considerable bone loss, thus, osteopenia and osteoporosis are serious complications after menopause. OBJECTIVES: To evaluate the effects of a daidzein metabolite equol on bone mass density (BMD) and markers of bone remodelling in an ovariectomized (ovx) rat model of postmenopausal bone loss and compare them with the effects of 17beta-estradiol. METHODS: Twenty-eight female Sprague-Dawley rats were ovx and fed soy-free chow only (control group, n = 8), or with the addition of oestradiol-3 benzoate (E2B) (10mg/kg, n = 10) or equol (400 mg/kg, n = 10). At baseline and after 6-week treatment period, proximal tibia and lumbar spine BMD were measured using computer tomography. Animals were then sacrificed, blood was collected and uteri were removed. RESULTS: Similarly to E2B, dietary equol decreased weight gain and showed mild uterotropic activity. E2B attenuated ovx induced BMD loss at proximal tibia whereas equol had no effect. At lumbar spine, however, equol not only attenuated trabecular bone loss but also increased its density. This effect was also apparent in animals treated with E2B. Cortical BMD at proximal tibia and lumbar spine were not very much influenced by ovx and treatment with E2B or equol did not induce significant changes at these sites. Plasma osteocalcin and type I collagen fragments (cross-laps) in equol treated animals did not differ from the controls whereas in E2B treated animals they were both significantly decreased. CONCLUSIONS: In spite of its mild uterotropic potential, dietary equol shows limited bone sparing effects in ovx rats.     

Dietary daidzein and puerarin do not affect pituitary LH expression but exert uterotropic effects in ovariectomized rats

OBJECTIVE: To investigate the potency of LH suppression, as an indirect measure of alleviation of postmenopausal vasomotor symptoms, as well as the uterotropic effects of two isoflavones: daidzein and puerarin in an ovariectomized (ovx) rat model and compare them with the effects of 17beta-estradiol benzoate (E2B). DESIGN: Eighty female Sprague-Dawley rats were ovx and divided into six different treatment groups and one control group (11-12 animals per group). Daidzein, puerarin and E2B were added to the soy free rodent chow in low and high doses (250 mg and 1000 mg per kg, 600 mg and 3000 mg per kg and 4.3 mg and 17.3 mg per kg, respectively). After 3 months of treatment, animals were sacrificed and using real time RT-PCR, pituitary LHbeta and uterine IGF-1, PR and C3 mRNA levels were measured. Additionally serum LH levels were measured in a radioimmunoassay. RESULTS: Both of our tested isoflavones at low and high doses had no effect on the expression of the pituitary LH at the mRNA and protein level. Only E2B at both doses significantly decreased pituitary LHbeta gene expression and serum LH levels. Daidzein and puerarin at high dose increased significantly uterine weights. Uterine IGF-1 gene expression was only upregulated in puerarin high group. Uterine PR mRNA levels were higher in animals fed with low dose daidzein and high dose puerarin. Uterine C3 gene expression was upregulated in animals fed with daidzein and puerarin at high doses. Although statistically significant, all these effects were however very discrete compared to those of E2B at low and high doses. CONCLUSION: We speculate that due to the lack of LH suppressing effects in our model, it is very unlikely for daidzein and puerarin to alleviate vasomotor symptoms in postmenopausal women. In contrast, due to their uterotropic effects, high dose consumption of commercially available preparations containing daidzein or puerarin may expose women with an intact uterus to the risk of endometrial hyperplasia.     

葛根素治疗突发性耳聋耳鸣的疗效观察

[目的 ]探讨葛根素治疗突发性耳聋、耳鸣的效果。 [方法 ]将突发性耳聋、耳鸣病人 10 0例随机分为治疗组和对照组 ,分别采用葛根素、低分子右旋糖酐及丹参进行治疗 ,观察两组耳聋、耳鸣症状改善情况。 [结果 ]突发性耳聋治疗组总有效率高于对照组 (P <0 .0 5 ) ,两组耳鸣总有效率无统计学意义。 [结论 ]葛根素治疗突发性耳聋、耳鸣均有明显疗效。     

Studies on the anti-tumor activities of the soy isoflavone daidzein on murine neuroblastoma cells.

Daidzein (4',7-dihydroxyisoflavone) and genistein (4',5,7-trihydroxyisoflavone) are two major isoflavones found predominantly in soy beans, as well as in certain traditional Chinese medicinal herbs and tea leaves. In the past decade, there have been extensive studies on the anti-tumor effects of genistein on cancers of the breast, prostate and colon in humans. However, the anti-tumor effects of daidzein on neuronal cancer cells and its action mechanisms remain poorly understood. In this study, daidzein was shown to inhibit the proliferation of a number of murine and human neuroblastoma cell lines in vitro. Using the murine neuroblastoma Neuro-2a (BU-1) cells as the cell model, daidzein was also found to prevent the cell cycle progression to G2/M phase and induced apoptosis of the neuronal tumor cells, as measured by flow cytometry and gel electrophoresis for fragmented DNA respectively. Taken together, our results showed that daidzein could exert pleiotropic effects on the murine neuroblastoma cells, including inhibition of cell proliferation, modulation of cell cycle check point regulation, and triggering of neuronal cell apoptosis.