Gene expression analysis of osteoblastic cells contacted by orthopedic implant particles.
Particles generated from orthopedic implants through years of wear play an essential role in the aseptic loosening of a prosthesis. We have investigated the biocompatibility of these orthopedic particles on different osteoblast-like cells representative of different stages of osteoblast maturation. We found the particles induced a caspase-dependent apoptosis of osteoblasts, with less mature osteoblasts being the most susceptible. An analysis of gene expression was performed on the less mature osteoblasts, which were in contact with the particles. We found that the particles had a profound impact on genes that code for inflammatory cytokines and genes involved in controlling the nuclear architecture. Results from this study suggest that the peri-implant osteolysis after a total joint replacement can be due in part to a decrease of bone formation and not solely to an overstimulation of bone resorption as is generally proposed. Development of new drugs that promote normal bone formation and osteoblast survival would possibly control peri-implant osteolysis, resulting in a better prognosis for patients with orthopedic implants.
Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla 92093, USA. pioletti@epfl.ch
Dominique P
DP
Pioletti
Lorenzo
L
Leoni
Davide
D
Genini
Hiroshi
H
Takei
Pinyi
P
Du
Jacques
J
Corbeil
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001672:Biocompatible Materials / Q000494:pharmacology; D053148:Caspase 3; D020169:Caspases; D018929:Cell Culture Techniques; D020869:Gene Expression Profiling; D006801:Humans; D007595:Joint Prosthesis; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D010014:Osteolysis / Q000209:etiology; D010316:Particle Size; D011475:Prosthesis Failure; D051381:Rats; D014025:Titanium / Q000494:pharmacology*
D001672:Biocompatible Materials; D014025:Titanium; C505407:CASP3 protein, human; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases