棘梨熱水抽出物が骨粗鬆症モデル卵巣摘出ラットに及ぼす影響

抄録

Firstly, the effects of cili (Rosa roxburghii) extract on bone metabolism and uterotrophic activity were studied in an ovariectomized rat model of osteoporosis. Secondly, cili extract was examined for the effects on osteogenic activity in UMR106 cells, a clonal osteoblastic line derived from rat osteosarcoma. Thirteen-week old female Wistar rats were randomly assigned to following five groups, i.e., shamoperated (Sham); ovariectomized (Ovx); Ovx and fed a diet containing 4. 5% ciliextract (Ovx +LC); Ovx and fed a diet containing 9. 0% cili extarct ( Ovx +HC);Ovx and injected daily with 5 μg of 17 β-etradiol / kg body wt./day (Ovx +E₂).The Ovx group showed significantly lower bone mineral density of the right femur than did the Sham group. Bone mineral density did not differ among the other groups from the Ovx group. These results suggest that cili extract is effective in preventing bone loss induced by ovarian hormone deficiency. Ovariectomy caused atrophy of the uterus. The atrophy was completely prevented by the E₂ treatment and partly prevented by the higher intake of cili extract. These results suggest that compared to E₂, cili extract has similar action on bone metabolism but less uterotrophic activity. Thus cili extract might be more suitable drug than estrogen for prevention of osteoporosis because estrogen administration is accompanied by severe adverse effects such as vaginal bleeding and carcinogenesis. In in vitro study, alkaline phosphatase activity was significantly increased in UMR106 cells by the additions of E₂ or cili extract. This implies that cili extract directly stimulates osteoblastic activity. In conclusion, cili extract contains a phytoestrogen which is effective in preventing bone loss due to ovarian hormone deficiency.