特定單脈衝電磁場與植物性雌激素對蝕骨細胞分化機轉之探討

Effects of Specific Single Pulsed Electromagnetic Field and Phytoestrogen Stimulation on Osteoclast Differentiation

黃莉婷(smile Huang)

指導教授 ： 張恆雄

中原大學/工學院/醫學工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400508

摘要

隨著年齡的增長亦或是婦女停經後會引發大量骨質流失，造成骨質疏鬆症。而骨質疏鬆所導致的脆弱骨質，以及隨之而來的骨折，已經被視為一種愈來愈重要之公衛健康問題。停經後之婦女愈來愈想以比較天然之療法來改善停經後之症候群。植物性雌激素 ( phytoestrogen ) 是這類療法中極具潛力之一顆新星，特別是從大豆中所獲取之異黃酮類 ( isoflavones )，被視為是一種選擇性雌激素接受體調節物 ( Selective estrogen receptor modulators: SERMs ) 。近來的研究也發現到很多類的植物性雌激素，特別是異黃酮類之genistein以及daidzein，具有雌激素之功能，卻沒有一般雌激素替代療法 ( hormone replacement therapy-HRT ) 之副作用，因此有愈來愈多之研究想探討是否可做為HRT之替代物來防治骨質疏鬆症。
根據植物性雌激素所擁有的這種作用之下，本研究試圖想要建立起一套體外蝕骨細胞培養模式來探討植物性雌激素對防治骨質疏鬆的效果，更希望能結合有關電磁場刺激的研究，將兩者的效用合併使防治骨質疏鬆的效果更好，期建立一套完整且有效的防治方法。
首先以1.3 Gauss強度之7.5 Hz單脈衝電磁場刺激加入含genistein和daidzein之骨髓細胞培養系統，每天刺激2小時，共刺激9天欲探討加了電磁場之不同種類的植物性雌激素是否會因此而影響蝕骨細胞之生成。
另外，也已完全相同的條件但多添加了抑制劑，欲探討加了電磁場之不同種類的植物性雌激素是否是藉由這些抑制劑的路徑而影響蝕骨細胞之生成。
而本研究中發現genistein和daidzein在濃度為10-5 M時，對蝕骨細胞的抑制效果最佳，其中又以daidzein的作用比genistein好。同時加入genistein和電磁場刺激與同時加入和daidzein電磁場刺激，可發現電磁場有更進一步抑制蝕骨細胞生成的效果。而當genistein和daidzein濃度提高時，加入電磁場刺激會有更好的效果。
在抑制劑中，環乙亞胺對genistein抑制蝕骨生成數目並無影響，但三苯氧胺卻有更加進一步抑制蝕骨生成數目，而genistein抑制蝕骨生成數目並不是經由蛋白質合成和protein kinase C這2條路徑所造成的。環乙亞胺可以block daidzein抑制蝕骨生成數目，相同的三苯氧胺也可block daidzein抑制蝕骨生成數目，因此daidzein抑制蝕骨生成數目是經由蛋白質合成和protein kinase C這2條路徑所造成的。
電磁場對於蝕骨細胞之影響，部分應該是經由蛋白質合成的路徑所造成之結果。而當genistein或daidzein濃度上升時，加入環乙亞胺的電磁場刺激並沒有更好的效果。而電磁場不是經由protein kinase C的路徑對蝕骨細胞生成造成影響。同樣的當genistein或daidzein濃度上升時，加入三苯氧胺的電磁場刺激並沒有更好的效果。

關鍵字

蝕骨細胞 ； 單脈衝電磁場 ； 植物性雌激素

並列摘要

Bone loss, as a natural part of aging and menopause, can result in osteoporosis. Osteoporotic bone fragility and fractures have been recognized a major public health issue. More and more menopausal women are seeking natural therapies to treat menopausal syndrome. Phytoestrogens are seen as a potential material in terms of natural therapies for treating the syndrome. In particular, isoflavones, a derivative of soybeans, are considered a kind of selective estrogen receptor modulators (SERMs). Recent studies have also cited that many types of phytoestrogens, especially genistein and daidzein in the isoflavones family, have the same functions of phytoestrogens and don’t have the side-effects of hormone replacement therapy (HRT). Therefore, more and more researches and experiments are conducted to discuss the possibility to treat osteoporosis with an alternative to HRT.
Therefore, this study aims to establish a vitro osteoclast culture models to evaluate the effectiveness of phytoestrogen treatment on osteoporosis and to provide an effective method of Osteoporosis prevention and treatment by combining the vitro osteoclast culture models with electromagnetic field stimulation.
Single pulsed electromagnetic fields (sPEMF) are confirmed to modulate the bone formation and bone resorption, which are carried out by osteoblasts and osteoclasts respectively. The underlying mechanisms, however, remain unclear up to date. Both of phytoestrogens and sPEMF are also combined to form a useful tool in the prevention of and therapy for osteoporosis.
In this study, murine bone marrow cells were exposed to sPEMF at 3.2 Gauss for 2h/day. All of the cells were cultured for 9 days in medium containing either vehicle, genisten, daidzein, cycloheximide, tamoxifen. To find out whether sPEMF and phytoestrogens can regulate osteoclasts formation.
The present of genistein (10-5 M), daidzein (10-5 M), genistein (10-5 M) plus sPEMF, or daidzein (10-5 M) plus sPEMF induced a remarkable decrease in osteoclasts formation. The present of genistein (10-5 M), daidzein (10-5 M) caused a significant decrease in osteoclasts formation, but this decrease was enhanced significantly by the addition of sPEMF.
The genistein (10-5 M), which induced decrease in osteoclasts formation, was not blocked by the present of cycloheximide (10-8 M) and tamoxifen (10-8 M). These results suggest that the effect of genistein to inhibit osteoclasts formation is not mediated through the pathway of protein synthesis and protein kinase C. The daidzein (10-5 M) induced decrease in osteoclasts formation was prevented completely by the present of cycloheximide (10-8 M) and tamoxifen (10-8 M). These results suggest that the effect of daidzein to inhibit osteoclasts formation is mediated through the pathway of protein synthesis and protein kinase C.
The sPEMF, which induced osteoclasts formation, is mediated through the pathway of protein synthesis; however, not form the pathway of protein kinase C.

並列關鍵字

Single pulsed electromagnetic fields ； Phytoestrogen ； osteoclast

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