• Journal of Nutrition and Health
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• 제39권4호
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• pp.338-346
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• 2006

The overall purpose of this study was to investigate the effects of level of isoflavones supplementation on bone metabolism in growing female rats. The effects of level of isoflavones supplementation on bone mineral density (BMD) and bone mineral content (BMC) were inspected in this study. Forty-five rats divided into three groups: Casein, $^1/{_2}IF$, IF. The serum and urine concentrations of calcium and phosphorus were determined. BMD and BMC were estimated by using PIXImus (GE Lunar Co, Wisconsin.) in spine and femur on 3, 6, 9 weeks after feeding. This study of results were as follows: The isoflavones supplementation level did not affect weight gain, mean food intake and food efficiency ratio. The serum concentration of calcium, phosphorus were not significantly different by different level of isoflavones supplementation. The urinary calcium and phosphorus excretion were not significantly different, too. Spine and femur BMD, BMC were not significantly increased by different level of isoflavones supplementation on 3 and 6 weeks after feeding. Spine BMD and spine BMC per weight, femur BMC per weight were significantly increased in the groups $^1/{_2}IF$ and IF at the ninth week after feeding, but there was no significant difference by different level of isoflavones supplementation. Spine BMD per weight and femur BMD per weight were significantly higher in the group of IF than in the group of Casein and $^1/{_2}IF$ at the ninth week after feeding. These results suggest that the group of IF with rich isoflavones supplementation was effective to the increase of BMD spine and femur in growing female rats, respectively.

• Journal of Nutrition and Health
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• 제38권5호
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• pp.344-351
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• 2005

The purpose of this study was to examine the impact of isoflavones on lipid concentrations and hepatic LDL receptor mRNA level in growing female rats. Twenty four rats (body weight $75\pm5g$) were randomly assigned to one of two groups, consuming control diet or isoflavones supplemented diet (57mg isoflavones/100g diet). All rats has been fed on experimental diet and deionized water ad libitum for 9 weeks. The concentration of triglyceride and total cholesterol were measured in serum and liver. Serum HDL cholesterol was measured. Hepatic LDL receptor mRNA level was tested by RT-PCR. Supplementation of isoflavones did not affect weight gain, mean food intake and food efficiency ratio. Serum total cholesterol and non-HDL cholesterol of isoflavones supplemented rats were significantly lower than those of control rats (p<0.05). But hepatic cholseterol was not influenced by supplementation of isoflavones. Hepatic LDL receptor mRNA level not significantly different between control group and isoflavones supplemented group. Therefore, isoflavones may be beneficial on serum cholesterol and non-HDL cholesterol lowering in growing female rats.

• Journal of Nutrition and Health
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• 제41권3호
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• pp.199-205
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• 2008

성장기 암컷 쥐를 대상으로 이소플라본 섭취수준에 따라 골대사 지표 및 골대사 관련 호르몬에 미치는 영향을 알아 보기 위해 실시한 연구 결과를 요약하면 다음과 같다. 1) 체중증가량과 식이섭취량, 식이효율은 이소플라본의 섭취수준에 따라 실험군간에 유의적인 차이가 없었다. 2) 골형성 지표인 혈청 ALP, osteocalcin은 이소플라본 섭취수준에 따라 실험군간에 유의적인 차이는 없었다. 3) 골흡수 지표인 DPD crosslink value도 이소플라본 섭취수준에 따라 실험군간에 유의적인 차이는 없었다. 4) 혈청 에스트로겐 농도, 부갑상선 호르몬과 인슐린유사 성장인자-I 농도는 이소플라본 섭취수준에 따라 유의적인 차이가 없었다. 5) 칼시토닌농도는 1IF군과 1/2IF군 보다 1IF군이 골형성과 골흡수에 유리한 경향을 나타내었고 칼시토닌과 성장호르몬이 유의적으로 증가하여 장기적으로는 골대사에 더 유리한 영향을 미칠 것으로 사료된다.

• 대한지역사회영양학회:학술대회논문집
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• 대한지역사회영양학회 2005년도 10th Anniversary International Symposium
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• pp.86-86
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• 2005

• Nutritional Sciences
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• 제6권1호
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• pp.25-30
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• 2003

The effects of soy-isoflavones, which are phytoestrogens derived from plants with a flavonoid structure, on cyclooxygenase -2 (COX-2) expression, PGE2 production, and mapkinases expression, were investigated in experimentally-induced atherogenic rats by feeding a high fat-high cholesterol diet. Female Sprague-Dawley rats were bilaterally ovariectomized; sham-operated animals were used as controls. Three weeks later, the animals were randomized to the following treatments for an eight-week experimental period: 17$\beta$-estradiol (200$\mu$ g/kg diet), low concentration of isoflavones (0.8g/kg diet), and high concentration of isoflavones (4.0g/kg diet). In the group supplemented with a high dose of isoflavones, COX-2 expression was down-regulated. This down-regulation was accompanied by a reduced expression of pERK1/2. In the second experiment using 48-week old female Sprague-Dawly rats, the effects of isoflavones and estrogen were compared in the basal estrogen-supplementation at the level of 600$\mu$ g/kg diet. Isoflavones induced the marked down-regulation of COX-2 protein and the decrease in $PGE_2$ production in estrogen supplemented states and this was followed by the down-regulation of p38 among mapkinases. The two different mapkinases are involved in the down-regulation of COX-2 depending on estrogen-deficient and estrogen supplemented states. This kind of COX-2 down-regulation by isoflavones was not observed in the different tissue, mammary glands. Further investigations on the relationship between COX-2 and biological activities such as vasodilation by isoflavonesin the absence or the presence of estrogen ave required in vivo system of female rats.

• 동의생리병리학회지
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• 제23권2호
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• pp.426-432
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• 2009

The overall purpose of this study was to investigate the effects of level of isoflavones supplementation on bone metabolism in osteoporosis rats. The effects of level of isoflavones supplementation on calcium and osteocalcin blood level, femur/body weight, bone mineral density(BMD) and bone strength were inspected in this study. This study classified 28 of 12 weeks-old male Sprague Dawley rats which have osteoporosis caused by ovariectomy into four groups of 7 rats and made the subjects medicated them isoflavone. Group I was non-treatment after osteoporosis(control); Group II was low-dose isoflavone(20 mg/kg) feeding after osteoporosis; Group III was middle-dose isoflavone(40 mg/kg) feeding after osteoporosis; Group IV was high-dose isoflavone(80 mg/kg) feeding after osteoporosis; In the calcium and osteocalcin level as one of bone formation indexes, there was a statistically significant difference between the group II, III, IV compared to group I. In respect to the femur/body weight, there was a statistically significant difference between the group II, III, IV compared to group I. In the bone mineral density and bone strength test, there was a statistically significant difference between the group II, III, IV compared to group I. The above results suggests that isoflavone medicated is effective to prevention and treatment of osteoporosis.

• Journal of Nutrition and Health
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• 제34권3호
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• pp.322-329
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• 2001

There is growing evidence that soy isoflavones play beneficial role in the prevention of cardiovascular disease. However, current data are not sufficient to determine the effective dose of isoflavone on improving plasma lipid profiles and total antioxidant capacity in Korean menopausal women. In the present study, 24 perimenopausal and 23 postmenopausal women were divided into 3 groups and were given soy isoflavone supplements of 100, 150, 200mg/day for 12weeks. Blood samples were taken before and after 6, 12weeks of soy isoflavone supplementation for analysis of total cholesterol, LDL cholesterol, HDL cholesterol, triglyceride and total antioxidant status(TAS). In the perimenopausal women, serum total cholesterol level decreased significantly in all three groups after 12weeks of isoflavone supplementation(p< 0.05). However, serum LDL cholesterol level significantly lowered only in 150 and 200mg groups, and serum triglyceride level decreased significantly in 200mg group(p<0.05). In the postmenopausal women, the 150mg isoflavone supplementation group demonstrated significant effects on lowering serum total cholesterol, LDL cholesterol levels and raising HDL cholesterol level after 12weeks of isoflavone supplementation(p<0.05). Two hundred mg isoflavone supplementation group had a significantly higher TAS than other groups in both perimenopausal and postmenopausal women. (Korean J Nutrition 34(3) : 322∼329, 2001)

• Nutrition Research and Practice
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• 제8권6호
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• pp.618-624
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• 2014

BACKGROUND/OBJECTIVES: Isoflavones are widely believed to be beneficial to human health, in relation to their antioxidant potentials. Exercise can cause an imbalance between reactive oxygen species (ROS) and antioxidants. This study was conducted in order to investigate the ability of isoflavones in amelioration of oxidative stress induced by exercise. MATERIALS/METHODS: Male Sprague-Dawley rats were assigned to one of four groups: isoflavone-free with no exercise (CON-sd), isoflavone-free with exercise (CON-ex), isoflavone-supplemented with no exercise (ISF-sd), and isoflavone-supplemented with exercise (ISF-ex). Animals exercised on the treadmill for 30 minutes per day, five days per week. TBARS as a marker of oxidative stress and antioxidant enzyme activity, including SOD, GSH-px, and catalase were determined in liver tissue. Serum lipid profile was also examined. RESULTS: A significant effect of isoflavone alone was observed on abdominal fat pad mass. ISF-ex had significantly less abdominal fat pad than CON-ex. Both exercise and isoflavone treatment had significant effects on lowering plasma triglyceride (TG), thus, the ISF-ex group had a significantly lower TG level than the CON-sd group, by 30.9%. However, no differences were observed in plasma cholesterol, HDL-C, and cholesterol/HDL-C ratio. Exercise, isoflavone, and exercise-isoflavone interaction effects were significant on thiobarbituric acid reactive substances (TBARS) (P = 0.001, 0.002, and 0.005, respectively). The CON-ex group showed a higher TBARS level than the other three groups. By contrast, in the ISF-ex group, TBARS was restored to the level of the ISF-sd or CON-sd group. Isoflavone had a significant effect on superoxide dismutase (SOD) (P = 0.022) and catalase activities (P = 0.049). Significantly higher SOD and catalase activities were observed in ISF-ex than CON-ex. SOD and catalase activities showed an inverse pattern of TBARS. Taken together, isoflavones increased the activities of SOD and catalase with concomitant decreases in TBARS, indicative of decreased oxidative stress. CONCLUSIONS: Isoflavone supplementation enhances antioxidant action with attenuation of exercise-induced oxidative stress, as measured by decreases in TBARS, and inhibits body fat accumulation and plasma TG increase. Antioxidative effects ascribed to isoflavones may be partially exerted via enhancement of antioxidant enzyme activities.

• Journal of Nutrition and Health
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• 제36권6호
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• pp.603-612
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• 2003

Postmenopausal women are at an increased risk of developing coronary artery disease. This is due to primarily dyslipidemia accompanying the loss of estrogen secretion. Soy isoflavones are known to have weak estrogenic effects. The purpose of this study is to investigate whether isoflavone supplement improves the risk of cardiovascular disease in hypercholesterolemic postmenopausal women. Subjects consisted of 39 Korean postmenopausal women with hypercholesterolemia (total cholesterol $\geq$ 200 mg/㎗ or LDL cholesterol $\geq$ 130 mg/㎗). Subjects were divided into 2 groups; placebo group (PG), isoflavone supplement group (IG). During 12 weeks, subjects were given placebo and 80mg isoflavone daily. Anthropometric measurement, blood sample analysis and dietary intake measurement were taken at baseline and after 12 weeks. After 12 weeks, systolic blood pressure was decreased significantly (p ＜ 0.01) and plasma HDL cholesterol level was increased significantly (p ＜ 0.05) in IG. But there were no significant changes in plasma total cholesterol, LDL cholesterol and triglyceride levels after isoflavone supplementation. There was a negative correlation between initial plasma HDL cholesterol level and the extent of plasma HDL cholesterol reduction in IG (r＝-0.572, p＝0.012). Atherogenic index (AI), total-/LDL- cholesterol ratio and LDL/HDL cholesterol ratio were improved significantly after isoflavone supplementation. In subjects whose initial plasma LDL cholesterol level were above 160 mg/㎗, plasma malondialdehyde (MDA) level were decreased and total antioxidant status (TAS) were increased significantly after isoflavone supplement (p ＜ 0.05). However there were no significant changes in flow-mediated dilator (FMD), the marker of endothelium-dependent vasodilation and nitroglycerine-mediated dilator (NMD), the marker of endothelium-independent vasodilation and the extent of DNA damage after isoflavone supplement. In conclusion, these results indicate that isoflavone supplement may decrease the risk of cardiovascular disease via improving blood pressure, HDL cholesterol level and AI in hypercholesterolemic postmenopausal women. Futhermore, in case of subjects with elevated LDL cholesterol level, isoflavone supplementation may have more antiatherogenic effects via improving antioxidant status.

• Journal of Community Nutrition
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• 제5권3호
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• pp.132-140
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• 2003

The objective of this study was to investigate the effect of soymilk and exercise on bone mineral density (BMD) in underweight college women of 19-22 years of age, who had lower bone mass. The BMD of the lumbar spine and femoral neck was measured for 52 underweight college women. Among them, 33 subjects, whose t-score value was below -1, were selected. Questionnaire survey, anthropometrical measurements, dietary recall, analysis of BMD, fasting serum osteocalcin and urinary deoxypyridinoline (DPD) were conducted before and after the 10 week study. The 33 subjects were divided into 2 groups： soymilk group (n=19), and soymilk ＋ exercise group (n=14). The soymilk group was given 400$m\ell$ soymilk containing 60mg of isoflavones on a daily basis and the soymilk ＋ exercise group exercised three times a week with a daily intake of 400$m\ell$ soymilk for 10 weeks. The average ages of the soymilk group and the soymilk ＋ exercise group were 21.1 years and 20.4 years, respectively and, there were no significant differences between the soymilk group and the soymilk ＋ exercise group in the areas of height, weight or Body Mass Index (BMI). At the baseline, the mean daily energy intake of the soymilk group and the soymilk ＋ exercise group was 1,597.9kcal (79.43％ of RDA) and 1,704.2kcal (85.2％ of RDA), respectively. The mean calcium intake of the soymilk group (408.3mg) was not significantly different from that of the soymilk ＋ exercise group (389.4mg). Despite the 400$m\ell$ soymilk supplementation, there were no significant changes of nutrient intake in either group after treatment. However, there were significant increases in BMD's of lumbar spine and femoral neck in both groups. There were some increases in the serum osteocalcin level and decreases in the urinary deoxypyridinoline level as well. BMD change of the soymilk group was not significantly different from that of the soymilk ＋ exercise group. In conclusion, supplementary intake of soymilk (containing 60mg of isoflavones) resulted in a significant increase in the BMD's of the lumbar spine and femoral neck in underweight college women with low bone mass. However, exercise did not result in any significant changes in the BMD's, implying the necessity for more intensive and specific long-term physical training for any substantial changes. Further investigation is necessary to determine the exercise that most strongly affects BMD.