Article

Urinary osteocalcin as a marker of bone metabolism.

Institute of Biomedicine, Department of Anatomy, University of Turku, Turku, Finland.
Clinical Chemistry (Impact Factor: 7.77). 03/2005; 51(3):618-28. DOI: 10.1373/clinchem.2004.043901
Source: PubMed

ABSTRACT Osteocalcin (OC) is produced by osteoblasts during bone formation, and circulating OC has been used in clinical investigations as a marker of bone metabolism. OC is excreted into urine by glomerular filtration and can be found in urine as midmolecule fragments.
We developed and evaluated three immunoassays (U-MidOC, U-LongOC, and U-TotalOC) for the detection of various molecular forms of urine OC (U-OC). We evaluated the association of U-OC with other markers of bone turnover and with bone mass in 1044 elderly women and studied seasonal and circadian variation of U-OC.
U-OC correlated with other bone turnover markers [Spearman correlation (r), 0.30-0.57; P <0.0001], demonstrating the association between U-OC and skeletal metabolism. There was also a significant association between bone metabolism assessed by U-OC quartiles and bone mass assessed by total body bone mineral content (P <0.0001). The seasonal effects appeared to be rather small, but we observed a significant circadian rhythm similar to the one reported for serum OC with high values in the morning and low values in the afternoon.
The three immunoassays had unique specificities toward different naturally occurring U-OC fragments. U-OC concentrations measured with any of these assays correlated with bone turnover rates assessed by conventional serum markers of bone metabolism. The measurement of OC in urine samples could be used as an index of bone turnover in monitoring bone metabolism.

0 Bookmarks
 · 
132 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: Previous studies have shown galanin (GAL) injections onto mouse calvaria increased bone thickness and osteoblast number. This study investigated the effects of the GAL receptor agonist galnon on bone loss using the ovariectomised (OVX) rat model. Methods: OVX rats were treated with either vehicle or galnon for 6 weeks via mini-osmotic pumps. Plasma osteocalcin concentrations, osseous cell gene expression, morphological and biomechanical properties of the skeleton were compared between the two groups. Results: Treatment with galnon increased RANKL:OPG gene ratio (p<0.001) plus expression of TNF-α (p<0.05) and cathepsin K (p<0.05). μCT analyses revealed galnon-treated OVX animals had reduced trabecular and cortical morphology compared to control animals. Biomechanically, galnon OVX animals required similar peak force to failure to that of control OVX animals although galnon treatment did enhance the mechanical properties of Young's modulus and ultimate tensile stress. Conclusions: Our research suggests that galnon, a GAL receptor agonist, may enhance osteoclastic bone resorption in OVX rats. Although galnon reduced bone volume, biomechanical testing revealed that bone of galnon-treated animals was mechanically superior per unit area. Taken together, galnon simultaneously improves the intrinsic quality of cortical bone whilst stimulating osteoclastic activity in the OVX rat model.
    Journal of musculoskeletal & neuronal interactions 06/2014; 14(2):162-172. · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective: To assess bone protective effects and intervention mechanism of α-Zearalanol in ovariectomized rat. Methods: 60 female SD rats were randomly separated into 6 groups:control group (n=10); ovariectomized group (OVX) (n=10); the OVX + E2 group(OVX + E2) (n=10); the high-dose OVX + α-ZAL group (OVX + HZ) (n=10); the moderate-dose OVX + α-ZAL group (OVX + MZ) (n=10); the low dose OVX + α-ZAL group (OVX + LZ) (n=10). α-ZAL was administered intragastrically to the rats. After 35 days, the total body Bone mineral density (BMD) was assessed in the rats. All sections were processed for hematoxylin-eosin staining (H.E.), and Basic fibroblast growth factor (bFGF), Tartrate-resistant acid phosphatase (TRAP), Bone morphogenetic proteins (BMP), and Bone Gla protein (BGP) immunoreactivity was assessed. Serum tumor necrosis factor-α (TNT-α) and bone specific alkaline phosphatase (BALP) levels were assessed using commercially available ELISA kits. Results: The expression of BMP and bFGF were significantly increased in OVX + MZ and OVX + LZ. The expression of TRAP, TNF-α, BGP and BALP were significantly decreased in OVX + MZ and OVX + LZ. BMD was significantly increased in OVX + MZ and OVX + LZ (vs. OVX, P
    01/2011;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective: To assess the bone protective effects and mechanism of Polygonatum Sibiricum Polysaccharide(PSP) in ovariectomized rat. Methods: 60 female SD rats were randomly separated into 6 groupsxontrol group (n=10); ovariectomized group (OVX) (n=10); the OVX + E2 group(OVX + E2) (n=10); the high-dose OVX + PSP group (OVX + HZ) (n=10); the moderate-dose OVX + PSP group (OVX + MZ) (n=10); the low dose OVX + PSP group (OVX + LZ) (n=10). PSP was administered intragastrically to the rats. After 35 days, the total body Bone mineral density (BMD) was assessed in the rats. All sections were processed for hematoxylin-eosin staining (H.E.) ,and Basic fibroblast growth factor (bFGF), Tartrate-resistant acid phosphatase (TRAP), Bone morphogenetic proteins (BMP), and Bone Gla protein (BGP) immunoreactivity was assessed. Serum tumor necrosis factor-α (TNF-α) and bone specific alkaline phosphatase (BAFP) levels were assessed using commercially available ELISA kits. Results: The expression of BMP and bFGF were significantly increased in OVX+HP. The expression of TRAP, TNF-α, BGP and BAFP were significantly decreased in OVX+HP. BMD was significantly increased in OVX+HP (vs. OVX, P
    01/2011;

Full-text (2 Sources)

Download
34 Downloads
Available from
May 21, 2014

Kaisa Ivaska