• Journal of Nutrition and Health
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• v.38 no.1
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• pp.30-39
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• 2005

The effects of different concentrations of estrogen supplementation to mature female rats or estrogen supplementation to ovariectomized rats on cyclooxygenase-2 (COX-2) expression, PGE$_2$ production and mapkinases expression were investigated in experimentally induced atherogenic rats with feeding a high fat. high cholesterol diet. In the first experiment using 48-week old mature rats, the supplementation of three different levels of estrogen was compared to the basal diet. The high concentration of estrogen supplementation induced the marked up-regulation of COX-2 protein and the increase in plasma PGE$_2$ production and this seems to be followed by the up-regulation of p38 among mapkinases. The regulation of bax showed in a reverse trend of COX-2 in heart tissues of mature female rats. In the second ex-perimental system, female Sprague-Dawley rats were bilaterally ovariectomized; sham-operated animals were used as controls. Three weeks later, the animals were supplied with basal diet to sham-operated control group and ovariectomized control group, and estrogen supplemented diet to ovariectomized group for an eight-week experimental period. In a group supplemented with a medium dose of estrogen, COX-2 expression was up-regulated. This up-regulation was accompanied by the elevated expression of pERK1/2. Bax was increased in estrogen-fed animals indicating bax might be involved in estrogen feeding state in ovariectomized rats. Further investigations on the relationship between COX-2 and biological activities such as vasodilation by estrogen are required in in vivo system of female rats at the various physiological states.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.709-714
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• 2005

Alteration of molecular markers related to apoptosis of in vivo normal system and in vitro cancerous system by soy-isoflavonoid with estrogen was investigated. Down-regulation of Bcl-2 was accompanied by decreased expression of COX-2 (cyclooxygenase-2) in mature female rats treated with soy-isoflavonoid and estrogen. In ovariectomized rat system, Bax was regulated by higher concentration of soy treatment. Bax up-regulation by soy-isoflavonoid genistein treatment was observed in MCF-7 mammary cancer cell system. Estrogen without soy induced similar pattern of Bax expression as soy-isoflavonoid in vivo, but exhibited opposite trend in vitro. These findings suggest soy-isoflavonoid may have potential to induce apoptosis at higher concentrations through up-regulation of Bax or down-regulation of Bcl-2 expressions depending on normal or cancerous state, and physiological status of rats.

• Nutritional Sciences
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• v.8 no.1
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• pp.16-22
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• 2005

The present study examined the effects of cyclooxygenase-2 (COX-2) inhibitor celecoxib or soy-isoflavones in the presence of estrogen on apoptosis related gene expression, COX-2 and mapkinase in 48-week old female rats. Expressions of bel-2 and bax proteins, which are known to be involved in the regulation of apoptosis, were investigated in mammary glands and heart tissues. The elevated expression of bel-2 expression was observed in mammary glands of celecoxib supplemented rats as well as soy-isoflavones. The mammary glands bel-2/bax ratio was found to be higher in celecoxib or soy-isoflavones supplemented rats. However, in heart tissues, expression of bel-2 and bax was in the order of control, celecoxib and soy-isoflavones. The up-regulation of COX-2 was observed in celecoxib or soy-isoflavones in mammary glands. 'The similar trend was not displayed with the mapkinase expression. In heart tissues, the down-regulation of COX-2 as well as mapkinase was observed in celecoxib or soy-isoflavones supplemented rats. Soy-isoflavones and celecoxib both had a similar regulatory pattern of bel-2, bax and COX-2 in mammary glands, and in heart tissues, only COX-2 exhibited a similar down-regulatory properly. These findings revealed that in estrogen sufficient state, celecoxib and soy-isoflavones might not exhibit proapoptotic potential or COX-2 inhibition in normal mammary glands.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.324-330
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• 2004

The purpose of this study was to investigate the effects of Porphyra tenera (PT) extracts on formation of collagen cross-link in ovariectomized rats. From day 3 until 42 after the ovariectomy, Sprague-Dawley female rats were randomly assigned to the following groups : sham-operated rats (Sham), ovariectomized control rats (OVX-control), ovariectomized rats supplemented with PT at 50 mg/kg bw/day (OVX-PT5O), 200 mg/kgbw/day (OVX-PT200). The PT ethanol extracts were orally administrated 1 mL per day. Body weight gain, food intake and food efficiency ratio were significantly different among the groups. The change of collagen content was studied in lung, bone, cartilage and skin of ovariectomized rats. The effects of PT extracts on the amount of collagen were examined by measuring the hydroxyproline, which is a specific amino acid existing in collagen. Pyridinoline is pyridinium cross-link formed in the mature form of collagen from lysine and hydroxylysine residues. Pyridinoline content was analyzed by HPLC. Pyridinoline content in bone collagen was decreased by ovariectomy but supplementation with the PT extracts was similarly increased to Sham. These results suggest that the PT supplementation could decrease bone loss in postmenopausal women.

• Journal of Life Science
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• v.18 no.11
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• pp.1578-1583
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• 2008

The purpose of this study was to investigate the effects of sea tangle (ST) extracts on formation of collagen and collagen cross-link in ovariectomized rats. From day 3 until 42 after the ovariectomy, Sprague-Dawley female rats were randomly assigned to the following groups: sham-operated rats(Sham), ovariectomized control rats (OVX-control), ovariectomized rats supplemented with ST at 50 mg/kg bw/day (OVX-ST50), 200 mg/kg bw/day (OVX-ST200). The ethanol extraxcr of ST was orally administrated at 1 ml/day. The change of collagen content was investigated in bone, cartilage and skin of ovariectomized rats. Effects of ST extract on the amount of collagen was examined by measuring the hydroxyproline, which is a specific amino acid existing in collagen. The ovariectomy resulted in a decrease in the levels of collagen content in bone and cartilage tissues. However, the supplementation with the sea tangle extract prevented the decrease in the collagen level in bone and cartilage tissues. Pyridinoline is pyridinium cross-link formed in the mature form of collagen from lysine and hydroxylysine residues. Although the pyridinoline content in bone collagen declined after ovariectomy, it was recovered to a normal level of Sham group by the supplementation with the ST extracts. In addition, the deoxypyridinoline content in bone collagen, which was reduced after ovariectomy was enhanced to normal level by the supplementation with the ST extract. These results was consistent with the conclusions based on estrogenic activities of ST.