Biological responses of preosteoblasts to particulate and ion forms ofCo‐Cr alloy

Abstract

This study compared the particulate and ion forms of a cobalt-chrome (Co-Cr) alloy on the differentiation/activation of preosteoblasts. Mouse preosteoblasts (MC3T3-E1) were cultured in an osteoblast-induction medium in the presence of particulate and ion forms of a Co-Cr alloy, followed by cell proliferation and cytotoxicity evaluations. The maturation and function of osteoblasts were assessed by alkaline phosphatase (ALP) assay and related gene expressions. Both particulate and ion forms of the metals significantly reduced the proliferation of MC3T3-E1 cells in a dose-dependent manner. Similarly, cells challenged with high concentrations of particles and ions exhibited a marked cytotoxic effect and diminished expression of ALP. Real-time (RT) polymerase chain reaction (PCR) data have suggested that cells with Co-Cr particles dramatically promoted over-expression of monocyte chemo-attractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), whereas Co(2+) ions treatment predominately up-regulated expressions of receptor activator of nuclear factor kappa-B ligand (RANKL), nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), and down-regulated expression of osteoprotegerin (OPG) and Osterix (Osx). Overall, this study provides evidence that both Co-Cr alloy particles and metal ions interfered with the MC3T3-E1 cells for their growth, maturation, and functions. Further, Co-Cr particles exhibited stronger effects on inflammatory mediators, while metal ions showed more influence on inhibition of osteoblast differentiation and promotion of osteoclastogenesis.

Particulate and ion forms of cobalt–chromium challenged preosteoblasts promote osteoclastogenesis and osteolysis in a murine model of prosthesis failure

“…31 It is therefore estimated that local Co(II) levels may be as high as 0.50 – 1 mM, implying that the concentrations utilized in this study were within a clinically significant range. 32 Further, our preliminary in vitro test 33 clearly suggested that particles (5 mg/ml) or ions (1mM) resulted in ubiquitous cell death compared to debris-free controls, while particles﹤0.15 mg/ml or ions ﹤32 μM did not show any influence on preosteoblast proliferation. We then determined to use particles concentrations at 0.3 and 2.5 mg/ml, in comparison with the metal ions at 62 and 500μM as physiological and clinical relevant low and high concentrations for the current study.…”

Gene Expression in Osteolysis: Review on the Identification of Altered Molecular Pathways in Preclinical and Clinical Studies

“…Although PMMA and CE particles behave similarly to Ti [34,49], ZrO 2 reduced pro-inflammatory genes more than Ti [54]. The addition of Ni to Co-Cr-Mo alloys reduced gene for TNFα [1] and Co-Cr alloy increased osteoclastogenesis to a greater extent than the ion form [40]. …”

“…Mouse macrophage cell lines (RAW264.7) were the most used [4,6,27,28,29,30,31,32,33,34,35,36,37], followed by OB precursors derived from mouse calvaria (MC3T3-E1) [27,28,38,39,40,41] and human (Saos-2 and MG-63) [1,42,43] or rat (ROS 17/2.8) [44] osteosarcoma and monocitic (THP-1) [20,45,46] cell lines. In addition, other studies also used primary cells: mouse [28,47] or human [42,48] OBs, mouse or rat bone-marrow-derived macrophages (BMM) [28,49,50,51], human MSCs [39,52], mouse [47] or human [53] FBs and mouse peritoneal macrophages [54].…”

“…In one study, mouse calvaria [4] were cultured in toto. Regarding the different wear particles used, Ti [4,6,27,28,29,30,31,32,33,38,39,42,45,50,52,53] was the most employed, followed by PE [20,34,37,43,47,48], PMMA [36,41,51] and Co-Cr alloy [1,40,46]. Three studies compared Ti effects with PMMA [49], zirconia (ZrO 2 ) [54] and aluminia ceramic (CE) [34] and one compared PE and hydroxyapatite (HA) particles [44].…”

“…In the first study, Co-Cr alloys and ions reduced the expression of OB differentiation markers (OPG, RUNX2 and OCN), while Co-Cr alloys and Co (II) also increased genes related to inflammation and osteoclastogenesis (TNFα, IL6, RANKL, CCL2 and NFATC1): this effect was more evident with Co-Cr alloy [40]. Co-Cr-Mo alloys with and without Ni increased the expression of gene for TNFα and the presence of Ni reduced their expression in OBs [1].…”