[The relationships between changes of serum osteoprotegerin, nuclear factor-kappa B ligand receptor activator, and age, menopause, bone biochemical markers and bone mineral densities in women aged 20 - 75].
OBJECTIVE
To investigate the relationships between the serum levels of osteoprotegerin (OPG), receptor activator of nuclear factor-kappa B ligand (RANKL) with age, menopause, bone biochemical markers and bone mineral densities (BMDs) in pre- and postmenopausal women and to determine the contributing factors for serum OPG and RANKL.


METHODS
504 pre- and postmenopausal women aged between 20 and 75 years were enrolled in this study. BMDs at lumbar spine and proximal femur were measured with dual-energy X-ray absorption meter. The serum osteocalcin (BGP), OPG, RANKL and urinary type I collagen (NTx) were also tested.


RESULTS
Age was positively related with serum OPG (r = 0.442, P < 0.001) and was negatively in association with serum RANKL (r = -0.263, P < 0.001). Postmenopausal women showed higher levels of serum OPG [(107.6 +/- 3.0) ng/L], while their serum concentrations of RANKL [(4.7 +/- 0.4) ng/L] and RANKL/OPG ratios (0.045 +/- 0.004) were significantly lower than those of premenopausal women [(72.0 +/- 1.8) ng/L, (5.8 +/- 0.3) ng/L and 0.099 +/- 0.008]. Neither serum OPG nor RANKL or RANKL/OPG was in association with BMDs at lumbar spine or proximal femur after adjustment of age, years-since-menopause (YSM) and body mass index. Serum OPG was positively related with urinary NTx/creatinine. Serum RANKL was negatively related with serum BGP. Serum OPG, RANKL and RANKL/OPG showed no differences among normal, osteopenic and osteoporotic postmenopausal women. In multiple regression analysis, YSM, age and bone markers were the independent contributors to OPG-RANKL system.


CONCLUSIONS
The elevation of serum OPG along with age might be a compensatary mechanism against the accelerated bone resorption, while the decreased level of serum RANKL might be helpful for restoring the reduced bone formation in postmenopausal women. YSM, age, together with bone tune-over markers were the main factors affecting serum concentrations of OPG and RANKL.
Liu
Jian-min
JM
Department of Endocrine and Metabolic Diseases, Rui-jin Hospital, Shanghai Clinical Center for Endocrine and Metabolic diseases, Shanghai Second Medical University, Shanghai 200025, China. ljmhh@sh163.net
Zhao
Hong-yan
HY
Ning
Guang
G
Zhao
Yong-ju
YJ
Chen
Ying
Y
Zhang
Lian-zhen
LZ
Xu
Man-yin
MY
Chen
Jia-lun
JL
D000328:Adult; D000367:Age Factors; D000368:Aged; D015519:Bone Density; D002352:Carrier Proteins / Q000097:blood*; D003094:Collagen / Q000097:blood; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D008562:Membrane Glycoproteins / Q000097:blood*; D008593:Menopause / Q000097:blood* / Q000502:physiology; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000097:blood*; D018124:Receptors, Tumor Necrosis Factor; D012044:Regression Analysis
D002352:Carrier Proteins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; C461299:urinary N-telopeptide of type I collagen, human; D015675:Osteocalcin; D003094:Collagen