Effects of Cimicifugae rhizoma on serum calcium and phosphate levels in low calcium dietary rats and on bone mineral density in ovariectomized rats

We studied the effects of ethyl acetate-(EtOAc) soluble fractions from methanol (MeOH) extracts of Cimicifugae rhizoma derived from two species - Cimicifuga heracleifolia Komarov and C. foetida L. - and four triterpenoids (1-4) isolated from them on the serum calcium (Ca) and phosphate (P) levels in low - Ca dietary rats. The EtOAc-soluble fraction from C. heracleifolia Komarov (HE) significantly drecreased Ca levels when administered. Similarly, the EtOAc-soluble fraction from C. foetida L. (FE) significantly lowered serum Ca levels at doses of 100 and 200 mg/kg/day, while the four triterpenoids (1-4) did the same at a dose of 25 mg/kg/day. Interestingly only 7,8-didehydro-24-O-acetylhydroshengmanol-3-O-beta-xyloside (4) showed a significant influence on serum P levels. The effects of HE and FE on the bone mineral density (BMD) of the lumbar spine (L 2-4) in ovariectomized rats were measured by dual energy X-ray absorptiometry (DXA). Rats treated with HE and FE showed a significant increase in BMD compared to untreated ovariectomized rats. BMD was lower in the latter than in sham-operated rats.