当前位置： SCI文献检索 > BONE期刊下所有文献 > Low osteocalcin/collagen type I bone gene expression ratio is associated with hip fragility fractures.

Low osteocalcin/collagen type I bone gene expression ratio is associated with hip fragility fractures.

Abstract：

INTRODUCTION:Osteocalcin (OC) is the most abundant non-collagenous bone protein and is determinant for bone mineralization. We aimed to compare OC bone expression and serum factors related to its carboxylation in hip fragility fracture and osteoarthritis patients. We also aimed to identify which of these factors were associated with worse mechanical behavior and with the hip fracture event. METHODS:In this case-control study, fragility fracture patients submitted to hip replacement surgery were evaluated and compared to a group of osteoarthritis patients submitted to the same procedure. Fasting blood samples were collected to assess apolipoproteinE (apoE) levels, total OC and undercarboxylated osteocalcin (ucOC), vitamin K, LDL cholesterol, triglycerides and bone turnover markers. The frequency of the apoε4 isoform was determined. Femoral epiphyses were collected and trabecular bone cylinders drilled in order to perform compression mechanical tests. Gene expression of bone matrix components was assessed by quantitative RT-PCR analysis. RESULTS:64 patients, 25 submitted to hip replacement surgery due to fragility fracture and 39 due to osteoarthritis, were evaluated. Bone OC/collagen expression (OC/COL1A1) ratio was significantly lower in hip fracture compared to osteoarthritis patients (p<0.017) adjusted for age, gender and body mass index. Moreover, OC/COL1A1 expression ratio was associated with the hip fracture event (OR ~0; p=0.003) independently of the group assigned, or the clinical characteristics. Apoε4 isoform was more frequent in the hip fracture group (p=0.029). ucOC levels were higher in the fracture group although not significantly (p=0.058). No differences were found regarding total OC (p=0.602), apoE (p=0.467) and Vitamin K (p=0.371). In hip fracture patients, multivariate analysis, adjusted for clinical characteristics, serum factors related to OC metabolism and gene expression of bone matrix proteins showed that low OC/COL1A1 expression ratio was significantly associated with worse trabecular strength (β=0.607; p=0.013) and stiffness (β=0.693; p=0.003). No association was found between ucOC and bone mechanics. Moreover, in osteoarthritis patients, the multivariate analysis revealed that serum total OC was negatively associated with strength (β=-0.411; p=0.030) and stiffness (β=-0.487; p=0.009). CONCLUSION:We demonstrated that low bone OC/COL1A1 expression ratio was an independent predictor of worse trabecular mechanical behavior and of the hip fracture event. These findings suggest that in hip fracture patients the imbalance of bone OC/COL1A1 expression ratio reflects disturbances in osteoblast activity leading to bone fragility.

journal_name

Bone

journal_title

Bone

authors

Rodrigues AM,Caetano-Lopes J,Vale AC,Vidal B,Lopes A,Aleixo I,Polido-Pereira J,Sepriano A,Perpétuo IP,Monteiro J,Vaz MF,Fonseca JE,Canhão H

doi

10.1016/j.bone.2012.08.129

subject

Has Abstract

pub_date

2012-12-01 00:00:00

pages

981-9

issue

eissn

8756-3282

issn

1873-2763

pii

S8756-3282(12)01169-6

journal_volume

pub_type

杂志文章

在线工具

Low osteocalcin/collagen type I bone gene expression ratio is associated with hip fragility fractures.