Department of Food Science, National Chiayi University, Chiayi, Taiwan.
Nutr Metab (Lond). 2009 Apr 9;6:15. doi: 10.1186/1743-7075-6-15.
In the literature, supplement of soy aglycons of isoflavone as estrogen agonists in improvement of serum biochemical attributes, liver antioxidative capacities and vaginal epithelium protection has been meagerly investigated. In this study, ovariectomized (OVX) rats were used as an animal model to simulate post-menopausal status. Supplementary health benefits of soy aglycons of isoflavone (SAI) on improvement of growth and serum biochemical attributes, enhancement of liver antioxidation-related capacities and protection of vaginal epithelium of the OVX rats were assessed.
As an in vivo study, 30 OVX Sprague-Dawley rats were distributed into OVX (positive control), OVX/LSAI (low SAI group - supplemented with 0.0135% SAI being equivalent to 80 mg per day for a 60 Kg-human), and OVX/HSAI (high SAI group - supplemented with 0.027% SAI) and 10 rats with sham operation as negative control fed with basal diet.
The average daily gain (ADG), feed intake and feed/gain ratio were higher for the OVX groups than the sham group (P < 0.05). Serum isoflavone concentrations of the OVX rats were increased by SAI supplementation. In comparison, significantly lower serum cholesterol and LDL (low-density lipoprotein) levels, and higher HDL (high-density lipoprotein) levels were detected for the rats of OVX/HSAI group (P < 0.05). SAI supplementation also increased iron chelating ability and decreased values of TBARS (thiobarbituric acid-reactive substance) (P < 0.05) of liver extracts. Liver catalase activity and total antioxidative activity (trolox equivalency) were enhanced by HSAI supplementation (P < 0.05). Decrease of vagina epithelial cellular linings of the OVX rats were noticeably improved by dietary supplementation with SAI.
Diets supplemented with soy aglycons of isoflavone have conferred health benefits to the OVX rats, in comparison to the sham rats fed with basal diet, by detection of higher serum isoflavone concentrations, significantly lower contents of serum cholesterol and LDL, and higher contents of serum HDL, increased iron chelating ability, lower contents of TBARS (thiobarbituric acid-reactive substance) and enhanced catalase and total antioxidative (as trolox equivalency) activities of the liver extracts, and protection of the epithelial cellular linings of vagina in the former rather than in the latter. This evidences that estrogen-agonist chemoprevention of menopausal-related cardiovascular diseases, decreased liver antioxidative capacities and epithelial degeneration of vagina could be achieved by dietary supplementation with soy aglycons of isoflavone.
在文献中，大豆苷元作为雌激素激动剂补充物对改善血清生化指标、肝脏抗氧化能力和阴道上皮保护的作用研究甚少。本研究以去卵巢（OVX）大鼠为动物模型模拟绝经后状态，评估大豆苷元（SAI）补充物对改善生长和血清生化指标、增强肝脏抗氧化相关能力和保护 OVX 大鼠阴道上皮的补充健康益处。
作为一项体内研究，将 30 只 OVX Sprague-Dawley 大鼠分为 OVX（阳性对照）、OVX/LSAI（低 SAI 组-补充相当于 80mg/天的 0.0135%SAI，用于 60kg 人）和 OVX/HSAI（高 SAI 组-补充 0.027%SAI）以及 10 只假手术（阴性对照）的大鼠，用基础饮食喂养。
与假手术组相比，OVX 组的平均日增重（ADG）、采食量和饲料/增重比更高（P<0.05）。SAI 补充使 OVX 大鼠的血清异黄酮浓度增加。相比之下，OVX/HSAI 组大鼠的血清胆固醇和 LDL（低密度脂蛋白）水平明显降低，HDL（高密度脂蛋白）水平升高（P<0.05）。SAI 补充还增加了肝脏提取物的铁螯合能力，并降低了 TBARS（硫代巴比妥酸反应物质）值（P<0.05）。HSAI 补充增强了肝脏过氧化氢酶活性和总抗氧化能力（trolox 等效物）（P<0.05）。SAI 饮食补充明显改善了 OVX 大鼠阴道上皮细胞衬里的减少。
与用基础饮食喂养的假手术大鼠相比，补充大豆苷元异黄酮的饮食通过检测更高的血清异黄酮浓度、显著降低血清胆固醇和 LDL 含量、提高血清 HDL 含量、增加铁螯合能力、降低 TBARS（硫代巴比妥酸反应物质）含量以及增强肝脏提取物的过氧化氢酶和总抗氧化（以 trolox 等效物计）活性和保护阴道上皮细胞衬里，为 OVX 大鼠带来了健康益处，表明通过膳食补充大豆苷元异黄酮可以预防绝经相关心血管疾病、降低肝脏抗氧化能力和阴道上皮退化的雌激素激动剂化学预防。
