Therapeutic effects of radix dipsaci, pyrola herb, and Cynomorium songaricum on bone metabolism of ovariectomized rats.
BACKGROUND
The objective of this study was to evaluate the effects of herbal medicines, such as Radix Dipsaci (RDD), Pyrola Herb (PHD), and Cynomorium songaricum decoction (CSD), on osteoporotic rats induced by ovariectomy (OVX).


METHODS
OVX or sham operations were performed on 69 virgin Wistar rats that were divided into six groups: sham (sham, n = 12), OVX control group (OVX, n = 12), and OVX rats with treatments (diethylstilbestrol, E2, n = 12; RDD, n = 11, PHD, n = 11, and CSD, n = 11). Non-surgical rats served as normal control (NC, n = 12). The treatments began four weeks after surgery and lasted for 12 weeks. Bone mass and bone turnover were analyzed by histomorphometry. Levels of protein expression and mRNA of OPG and RANKL in osteoblasts (OB) and bone marrow stromal cells (bMSC) were evaluated by immunohistochemistry and in situ hybridization.


RESULTS
Compared to NC and sham rats, trabecular bone formation was significantly reduced in OVX rats, but restored in E2-treated rats. Treatment with either RDD or PHD enhanced trabecular bone formation remarkably. No significant change of bone formation was observed in CSD-treated rats. OPG expression of protein and mRNA was reduced significantly in OB and bMSC of OVX control rats. RANKL expression of protein and mRNA was increased significantly in OB and bMSC of OVX control rats. These effects were substantially reversed (increased in OPG and decreased in RANKL) by treatment with E2, RDD, or PHD in OB and bMSC of OVX rats. No significant changes in either OPG or RANKL expression were observed in OB and bMSC of OVX rats treated with CSD.


CONCLUSIONS
Our study showed that RDD and PHD increased bone formation by stimulating overexpression of OPG and downregulation of RANKL in OB and bMSC. This suggests that RDD and PHD may be used as alternative therapeutic agents for postmenopausal osteoporosis.
Institute of Basic Theory, China Academy of Chinese Medical Sciences, South Small Street 16, Dongzhimennei, Dongcheng District, Beijing 100700, Peoples Republic of ChineChina.
Meijie
M
Liu
Gary Guishan
GG
Xiao
Peijing
P
Rong
Zhiguo
Z
Zhang
Jiazi
J
Dong
Hongyan
H
Zhao
Honghong
H
Li
Yan
Y
Li
Jinghua
J
Pan
Hong
H
Liu
Wenlai
W
Wang
Qinglin
Q
Zha
Dahong
D
Ju
D000818:Animals; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D031482:Cynomorium; D004054:Diethylstilbestrol / Q000494:pharmacology / Q000627:therapeutic use; D049917:Dipsacaceae; D004365:Drugs, Chinese Herbal / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D059630:Mesenchymal Stem Cells / Q000187:drug effects / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects; D010024:Osteoporosis / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D010052:Ovariectomy; D008517:Phytotherapy; D031828:Pyrola; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D004365:Drugs, Chinese Herbal; D053245:RANK Ligand; D012333:RNA, Messenger; D004054:Diethylstilbestrol