Protective effects of Polygonatum sibiricum polysaccharide on ovariectomy-induced bone loss in rats

To assess the ability of traditional Chinese medicine Polygonatum sibiricum polysaccharide to prevent bone loss in the ovariectomized rat. PSP was administered intragastrically to the rats. After 35 days, the total body bone mineral density (BMD) was assessed in all of the rats. All sections were processed for immunohistochemistry and hematoxylin-eosin staining (H.E.). BMD was lower in the ovariectomized group (OVX, 0.163 g/cm2), the group that received a moderate dose of PSP on OVX animals (OVX + MP, 0.163 g/cm2) and the group that received a low dose of PSP on OVX animals (OVX + LP, 0.162 g/cm2) than in the sham-operated group (SHAM, 0.180 g/cm2), the OVX + E2 group (OVX + E2, 0.176 g/cm2) and the group that received a high dose of PSP on OVX animals (OVX + HP, 0.174 g/cm2) (P < 0.05). Clear arrangements of bone trabeculae were observed in the OVX + E2 and OVX + HP. The expression of bone morphogenetic proteins (BMP) and basic fibroblast growth factor (bFGF) in the OVX, OVX + MP and OVX + LP was down regulated compared to the SHAM, OVX + E2 and OVX + HP (P < 0.05). The rats in the OVX + E2 and OVX + HP had lower levels of bone Gla protein (BGP), bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRAP) and tumor necrosis factor α(TNF-α) expression than the rats in the OVX, OVX + MP and OVX + LP (P < 0.05). This experiment demonstrates that the administration of PSP to ovariectomized rats reverses bone loss and prevents osteoporosis.