[Effect of the Wnt/LRP5/β-catenin signaling pathway on the pathogenesis of postmenopausal osteoporosis].
OBJECTIVE
To investigate the role of the Wnt/LRP5/β-catenin signaling pathway in the pathogenesis of postmenopausal osteoporosis.


METHODS
Fifty female Wistar rats aged 6-month-old, were randomly divided into control group (NS, n = 24) and ovariectomized group (NOVX, n = 26), NOVX underwent bilateral ovariectomy. At 0, 4 and 8 weeks, all of rats were measured blood estrogen (E(2)) and bone mineral density (BMD), 4 and 8 weeks, low density lipoprotein receptor-related protein 5 (LRP5), β-catenin and Runx2 mRNA in bone were measured respectively by reverse transcription (RT)-PCR.


RESULTS
In 4 and 8 weeks, compared with NS which had (117 ± 29) and (114 ± 15) pmol/L in E(2) level, (0.098 ± 0.016) and (0.095 ± 0.028) g/cm(2) in BMD, NOVX had significantly decreased to (92 ± 15) and (95 ± 22) pmol/L in E(2) level (P < 0.05), (0.076 ± 0.016) and (0.052 ± 0.013) g/cm(2) in BMD values (P < 0.01). And bone tissue LRP5, β-catenin and Runx2 mRNA expression was 1.02 ± 0.06, 1.04 ± 0.05, 1.07 ± 0.21 in NS, NOVX was significantly reduced to 0.97 ± 0.04, 0.58 ± 0.05, 0.86 ± 0.03 (P < 0.05).


CONCLUSIONS
Wnt/LRP5/β-catenin signaling pathway may be important in the pathogenesis of postmenopausal osteoporosis.
Department of Endocrinology, Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
Yan
Y
Wang
Yan
Y
Liu
Jian-xia
JX
Ma
Bao-xin
BX
Li
Yu-kun
YK
Li
D000818:Animals; D015519:Bone Density; D001842:Bone and Bones / Q000378:metabolism*; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D004958:Estradiol / Q000097:blood; D005260:Female; D005786:Gene Expression Regulation; D060492:Low Density Lipoprotein Receptor-Related Protein-5 / Q000235:genetics / Q000378:metabolism*; D010024:Osteoporosis / Q000209:etiology* / Q000378:metabolism / Q000517:prevention & control; D010052:Ovariectomy; D017698:Postmenopause; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D060449:Wnt Signaling Pathway; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
D050659:Core Binding Factor Alpha 1 Subunit; C495268:Ctnnb1 protein, rat; D060492:Low Density Lipoprotein Receptor-Related Protein-5; C555484:Lrp5 protein, rat; D012333:RNA, Messenger; C493717:Runx2 protein, rat; D051176:beta Catenin; D004958:Estradiol