Associations of Serum Osteocalcin and Polymorphisms of<b> </b>the<b><i> Osteocalcin</i></b> Gene with Bone Mineral Density in Postmenopausal and Elderly Chinese Women

Abstract

Background: The aims of this study were: (1) to evaluate the association of serum osteocalcin with bone mineral density (BMD) and markers of bone metabolism in postmenopausal and elderly Chinese women, and (2) to observe the relationships of single-nucleotide polymorphisms (SNPs) in and around the osteocalcin gene with osteocalcin and BMD. Methods: A cross-sectional study was conducted with 725 postmenopausal Chinese women. Five SNPs (rs1543294, rs1800247, rs759330, rs2842880, and rs933489) of the osteocalcin gene were genotyped. Serum osteocalcin and intact parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH)D], and type I collagen containing cross-linked C-telopeptide (β-CTX) were measured. The BMD of the lumbar spine and proximal femur was measured by dual-energy X-ray absorptiometry. Results: Osteocalcin was positively correlated with serum phosphorus (p = 0.001), alkaline phosphatase (ALP; p < 0.001), PTH (p = 0.002) and β-CTX (p < 0.001), and negatively correlated with BMD at the lumbar spine (p < 0.001) and total hip (p = 0.002). No significant association was obtained between the SNPs, haplotypes of the osteocalcin gene, and BMD or osteocalcin. Conclusion: Our results suggest that osteocalcin was positively correlated with serum phosphorus, ALP, PTH, and β-CTX, but negatively correlated with BMD at the lumbar spine and total hip. Common genetic variants of the osteocalcin gene may not be a major contributor to variations in serum osteocalcin or BMD in postmenopausal and elderly Chinese women.

Effects of Premating Calcium and Phosphorus Supplementation on Reproduction Efficiency of Grazing Yak Heifers

“…Osteocalcin can bind strongly to hydroxyapatite to bridge the matrix and mineral fractions of bone tissue [ 45 ]. Serum levels of osteocalcin have been proven to be closely related to the bone formation rate [ 46 ], and they are positively correlated with serum P levels [ 47 ], which is consistent with the findings of this study, suggesting that bone formation could be improved in the MCP group. Previous studies showed that phosphorus-deficient diets could reduce bone formation to maintain serum levels of Ca and P in lactation cows [ 48 ] and decrease the serum osteocalcin levels in growing–finishing pigs [ 49 ].…”

A meta-analysis of serum osteocalcin level in postmenopausal osteoporotic women compared to controls

“…Last but not least, the carboxylation status of sOC was not mentioned in any of the included studies. As a matter of fact, both OC and unOC in the circulation have been reported to correlate with each other [37, 38] and with bone quality [39, 40] but most of the conventional sOC assay kits are designed for total sOC while unOC can only be evaluated with special techniques [41, 42]. The result of this meta-analysis might not be significantly influenced by the carboxylation status of sOC as the same OC assay kit was adopted in PMO and control groups within each individual study.…”

Associations between bone-alkaline phosphatase and bone mineral density in adults with and without diabetes

“…When Lumachi et al [ 12 ] evaluated BAP along with other bone formation markers (osteocalcin, type I collagen and BMD) in elderly men with no history of fractures, they found no relationship at all between BAP and bone density in this population. In a similar comparison among elder Chinese women, Zhang et al [ 20 ] found a positive correlation between osteocalcin and BAP but a negative correlation with total and subregional BMD (at lumbar spine and total hip), suggesting that osteocalcin gene variants may not contribut to BMD in postmenopausal and elderly Chinese women. Those authors also found that BAP was a useful parameter for evaluating age-related changes in bone turnover.…”