Effects of combined intervention of soy isoflavone and moderate exercise on bone loss in ovariectomized mice

身体脂肪堆积和骨质流失通常都与绝经后雌激素缺乏有关。在这项研究中，我们研究了大豆黄酮，植物雌激素之一，和适度的运动干预是否表现出协同作用的身体组成和骨量在卵巢切除（OVX）小鼠。将8周龄雌性小鼠分为6组：（1）假手术（sham）;（2）OVX ;（3）接受大豆膳食的OVX（OVX+ISO）;（4）在跑步机上锻炼的OVX（OVX+EX）;（5）给予运动和锻炼的OVX（OVX+ISO&EX）;和（6）皮下用17 β-雌二醇处理的OVX（OVX+E2）。采用双能X线骨密度仪（DXA）测定身体成分和骨密度（BMD）。干预6周后，OVX组大鼠的体脂（%）显著高于Sham组。运动干预和单用E2干预部分抑制了OVX诱导的体脂增加，联合干预以及E2治疗完全恢复了脂肪量到假手术水平。OVX组与OVX+ISO、OVX+EX、OVX+E2组相比，全身瘦体重无显著性差异，但OVX+ISO&EX组明显高于其他各组。全身、腰椎或股骨的BMD均明显降低，运动或单纯运动干预可部分抑制骨丢失。然而，联合干预完全恢复了骨量的水平，假E2。血清总胆固醇显著增加OVX，并通过联合干预或E2治疗恢复正常。这些结果表明，大豆蛋白和运动的联合干预防止了全身的体脂肪积累，增加了瘦体重和恢复了骨量，并降低了OVX小鼠的高血清胆固醇。

Body fat accumulation and bone loss are both often associated with estrogen deficiency following menopause. In this study, we examined whether soy isoflavone, one of the phytoestrogens, and moderate exercise interventions exhibit cooperative effects on body composition and bone mass in ovariectomized (OVX) mice. Eight week-old female mice were assigned to six groups : (1)sham-operated (sham) ; (2)OVX ; (3)OVX with received a soy isoflavone diet (OVX+ISO) ; (4)OVX with exercised on a treadmill (OVX+EX) ; (5)OVX with given both isoflavone and exercise (OVX+ISO&EX) ; and (6)OVX with treated with 17 β-estradiol subcutaneously (OVX+E2). Body composition and bone mineral density (BMD) were estimated by dual-energy X-ray absorptiometry (DXA). After the 6-week intervention, whole body fat (%) in the OVX group showed significantly higher than that in the sham group. Intervention of exercise and isoflavone alone partially inhibited OVX-induced body fat gain, and the combined intervention as well as E2 treatment completely restored fat mass to the sham level. Lean body mass in the whole body was not different in OVX group compared with that in OVX+ISO, OVX+EX and OVX+E2 groups, but it was significantly higher in OVX+ISO&EX than in other groups. BMD of the whole body, lumbar spine or femur showed significantly reduced by OVX, and the bone loss was partially inhibited by intervention of exercise or isoflavone alone. However, the combined intervention completely restored the bone mass to the level of sham, as did E2. Serum total cholesterol was significantly increased by OVX, and which was normalized by the combined intervention or E2 treatment. These results demonstrate that combined intervention of soybean isoflavone and exercise prevented body fat accumulation in the whole body with an increase in lean body mass and restoration of bone mass, and reduced high serum cholesterol in OVX mice.