OBJECTIVETo investigate the preventive and therapeutic effect of Bushen Ningxin decoction (BSNX) on postmenopausal osteoporosis.

METHODSThe BALB/c female mice postmenopausal osteoporosis model was established. The model mice were treated by BSNX, with 17beta-estradiol (E2) and normal saline as positive and negative control, respectively. All mice were sacrificed after 12 weeks' treatment, the serum cytokines Th1/Th2, bone mineral density (BMD) of vertebrae (L3 - 4) and left femur were determined, and morphological quantitative analysis of bone tissue of right femurs was performed and osteoprotegerin (OPG) mRNA expression in tibia was detected by semi-quantitative RT-PCR. The ratio in weight of uterus to body was calculated, and uterine slice was gotten for histological observation.

RESULTSAs compared with the negative control group, the level of interferon-gamma (IFN-gamma) was significantly increased (P < 0.01) and interleukin-4 (IL-4) decreased (P < 0.05) in the BSNX treated group. The BMD of mice were improved, area of bone trabecula and OPG mRNA expression were increased in the BSNX treated and E2 treated group (P < 0.01). But the uterus in the former was significantly smaller than that in the latter (P < 0.01), while it was not significantly different to that in the negative control group.

CONCLUSIONBSNX can selectively prevent and cure the postmenopausal osteoporosis, it has no or slight stimulation on uterus. The mechanism may relate with its effects in regulating the deviation of Th1/Th2, enhancing the OPG expression and inhibiting the activity of osteoclasts.