Response of MC3T3‐E1 osteoblasts, L929 fibroblasts, and J774 macrophages to fluoride surface‐modified AZ31 magnesium alloy

Abstract

The present work evaluates the biocompatibility of a fluoride surface-modified AZ31 magnesium alloy (AZ31HF) with different cell lines that coexist in the implant environment to test its potential use as a biodegradable and absorbable biomaterial for bone repair. A clear stimulation of cell proliferation and an enhancement of the mitochondrial respiratory activity were observed when mouse osteoblasts (MC3T3-E1), fibroblasts (L929), and macrophages (J774) cell lines were cultured with the modified alloy. No significant change in apoptosis or viability rates was observed when osteoblasts and fibroblasts cultures were grown in the presence of this alloy. A proteomic analysis of the MC3T3-E1 cell extracts cultured in the presence of AZ31HF showed an overexpression of proteins related with the mineralization process, which is a necessary step for bone repair. An increase in the lactate dehydrogenase activity was observed in the MC3T3-E1 and J774 cell cultures that could be a response of the oxidative stress produced by the presence of the material. This stress could be related to the increase observed in the respiratory mitochondrial activity or respiratory burst measured in theses cultures that indicate damage in the cell membranes and subsequently some cell death. Results reported here, for and against AZ31HF, should be taken into account when considering the potential use of this modified alloy in bone repair applications.

Osteoblasts MC3T3-E1 Response in 2D and 3D Cell Cultures Models to High Carbon Content CoCr Alloy Particles. Effect of Metallic Particles on Vimentin Expression

“…A concentration of 2 mg/ml of wear particles produced an increase of almost 4 folds over the control assay, where cells were no exposed to any particles (Figure 4, left panel). This increase in the respiratory activity produced by the exposure to wear particles could be related to a response of oxidative stress produced by the cells due to the exposure to some metallic alloys (Lozano et al, 2013). In the case of bulk particles (Figure 4, right panel) a comparable increase in the respiratory activity was also observed.…”

“…Both particles samples produced an increase in the mitochondrial activity that can be interpreted as an oxidative stress response (Lozano et al, 2013). Wear particles produced an increase in the respiratory activity that seemed to be directly related to the concentration of particles to which osteoblasts were exposed, a dose-dependence that was no observed for bulk particles where the increase on respiratory activity seemed weakened.…”

Macrophage Biocompatibility of CoCr Wear Particles Produced under Polarization in Physiological Hyaluronic Acid Solution

“…Application of anodic polarization during tribocorrosion assays generated wear particles from CoCr alloy that affected macrophage mitochondrial activity response. It is well known that mitochondrial activity measurement is directly proportional to the number of metabolically active cells in culture that is for this reason a measure of cell viability and biocompatibility [27]. As shown in Figure 7 panel A, wear particles derived from HA solution tests produced a progressive reduction in the respiratory response of macrophages that is wear particle dosedependent.…”

“…Cytotoxicity induced by HCCoCr wear particles obtained in the different tribocorrosion tests was analyzed by measuring LDH activity released from cells ( Figure 6), whose levels increase upon plasma membrane damaged being a sign of cell death [27]. As is shown in Figure 6, exposure of macrophages cultures to wear particles induced a degree of cytotoxicity that was mainly dependent of the conditions used during wear-corrosion assays and particle concentration.…”

“…Wear-particles obtained from the wear-corrosion tests were centrifuged and the particle pellet (WST-1 assay) and plasma membrane damage (LDH assay) were used to evaluate the biocompatibility and cytotoxicity respectively as described below [27].…”