Undercarboxylated Osteocalcin ELISA Kit (ucOC)

INTENDED USE

Human undercarboxylated osteocalcin ELISA kit can measure concentrations of ucOC (undercarboxylated osteocalcin) present is plasma, serum, biological fluids or tissue homogenate samples.

INTRODUCTION

Osteocalcin is an abundant noncollagenous bone matrix protein secreted by osteoblasts during bone formation. Through vitamin K-dependent γ-carboxylation of specific glutamic acid residues, osteocalcin binds hydroxyapatite with high affinity, comprising 10-20% of the total bone protein matrix. The resulting γ-carboxyglutamic acid content correlates with mineralization capacity. However, a fraction of synthesized osteocalcin evades this post-translational modification to persist in circulation as ucOC.

Long presumed inert, a paradigm shift occurred upon discovering ucOC biological activity as an endocrine hormone. Interacting with receptors on pancreatic beta cells, it stimulates insulin secretion and improves insulin sensitivity. Separately, it promotes testosterone production in Leydig cells.  In line with such roles, higher ucOC associates with lower adiposity, fewer metabolic disturbances, and better physical function in large human cohorts.

Beyond influencing local bone turnover as osteoblasts take up and carboxylate ucOC, circulating ucOC also promotes systemic phosphate homeostasis by stimulating renal tubular phosphate reabsorption. Given the array of metabolic benefits from ucOC—which requires vitamin K sufficiency—there is interest in developing ucOC as a biomarker of skeletal health reflecting nutritional status. Clinical trials are also underway testing ucOC-therapy for conditions like diabetes, sarcopenia or fracture recovery where low bone turnover and vitamin K deficiency likely contribute to pathogenesis.

CONTENT

All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

• One 96-Well Plate: Pre-coated with anti- ucOC antibody.
• Standards: Lyophilized recombinant.
• Sample/Standard Dilution Buffer.
• Biotinylated-labelled Antibody.
• Antibody Dilution Buffer.
• HRP-Streptavidin Conjugate (SABC).
• SABC Dilution Buffer.
• TMB Substrate.
• Wash Buffer (25x).
• Plate Sealer.
• Product Instructions.

TYPICAL RESULTS

For this ucOC ELISA kit, it is recommended that a standard curve is generated for each assay carried out.

Standard Curve: 0, 0.156, 0.312, 0.625, 1.25, 2.5, 5, 10 ng/ml.
Reactivity: Human
Sensitivity: 0.094 ng/ml
Range: 0.156 – 10 ng/ml
Principle: Sandwich, Double Antibody
Application: Research Use Only.

ASSAY CHARACTERISTICS

– Specificity: Highly specific for ucOC, no cross reactivity or interference between ucOC and analogues was detected.
– Recovery: Serum (85 – 101%), EDTA Plasma (89 – 101%), Heparin Plasma (86 – 104%).
– Linearity: Serum (85 – 100%), EDTA Plasma (91 – 100%), Heparin Plasma (80 – 90%).
– Precison Intra-Assay: CV < 8%
– Precison Inter-Assay: CV < 10%

REFERENCES

1. Undercarboxylated osteocalcin and ibandronate combination ameliorates hindlimb immobilization-induced muscle wasting. J Physiol. (2023) 601 (10): 1851-1867. Lin X., et al.
2. Functional tooth number in the posterior region associated serum ucOC levels. Int J Implant Dent. (2022) 8 (1): 50. Nakamura M., et al.
3. Molecular Pathways and Roles for Vitamin K2-7 as a Health-Beneficial Nutraceutical: Challenges and Opportunities. Front Pharmacol. (2022) 13: 896920. Jadhav N., et al.
4. No Evidence of Association Between Undercarboxylated Osteocalcin and Incident Type 2 Diabetes. J Bone Miner Res. (2022) 37 (5): 876-884. Babey M.E., et al.

ADDITIONAL INFORMATION

• Full Name: Undercarboxylated Osteocalcin ELISA Kit (ucOC)
• Reactivity: Human
• Sample Type: Plasma, Tissue Homogenates, Serum, Biological Fluids
• Sensitivity: 0.094 ng/ml

OTHER RELATED ELISA KITS

• LDHA ELISA Kit
• Nephrin ELISA Kit
• Semaphorin-3G ELISA Kit