Antiosteoporotic activity of Er-Xian Decoction, a traditional Chinese herbal formula, in ovariectomized rats

The antiosteoporotic effect of a herbal formula, Er-Xian Decoction (EXD), in ovariectomized (OVX) rats model of osteoporosis was investigated. The rats were divided into Sham and OVX groups. The OVX rats were further sub-divided into four groups administered orally with water, nylestriol (1 mg/kg, weekly) or EXD (300, 600 mg/kg, daily) for 12 weeks. In OVX rats, the increases of body weight, serum BGP and ALP were significantly decreased by EXD treatment. In OVX rats, atrophy of uterus and descent of BMD were suppressed by treatment with EXD and nylestriol. In addition, EXD completely corrected the decreased concentration of calcium, phosphorus, and estradiol in serum observed in OVX rats. EXD also significantly increased biomechanical strength comparable to the Sham group. This was also confirmed by histological results that showed its protective action. The findings assessed on the basis of biochemical, bone mineral density, biomechanical, and histopathological parameters strongly suggested that EXD had a definite antiosteoporotic effect, which is similar to estrogen.