Epigenetic changes of osteoblasts in response to titanium surface characteristics.

ABSTRACT

We aimed to investigate the influence of titanium surface characteristics on epigenetic mechanisms and DNA damage/repair pathways. Osteoblast-like cells (MG63) were incubated on glass, smooth titanium, and minimally rough titanium discs, respectively, for 0, 1, 6, and 24 hr. The presence of double-stranded DNA damage (γH2AX), DNA repair (Chk2), and epigenetic markers (AcH3 & DNMT1) were investigated using immunofluorescence. There were no Chk2-positive cells on the minimally rough titanium surfaces at all-time points, in comparison to glass and smooth titanium. Total γH2AX-positive cells on minimally rough titanium gradually decreased as incubation time increased, on the contrary to smooth titanium. Minimally rough titanium surfaces induced cytoplasmic staining of DNMT1 up to 99% at 24 hr. For epigenetic markers related to the DNA damage/repair pathway, minimally rough titanium surfaces showed the lower percentage of AcH3-positive cells compared to glass and smooth titanium surface. The findings in the current study show that titanium surface characteristics indeed influence DNA damage and the DNA repair pathway, including epigenetic factors.