| dc.description.abstract | Resin-based dental materials are a common first choice when restoring dental function. Both dental
personnel and patients are exposed to methacrylate monomers, one main component in these materials. A
concern regarding possible side effects these materials may induce has been the motivation of several in
vitro studies. A cytotoxic potential have been described in vitro, but detailed knowledge regarding
molecular interactions of monomers in living cells remain scarce. A suggested mechanism, however,
involves thiol-reactivity and increased levels of oxidative stress. 2-Hydroxyethylmethacrylate (HEMA) is
shown to form spontaneous adduct formation towards the thiol-group in glutathione (GSH), and it is
speculated if similar reactions between proteins and HEMA occurs. The aim of this study was to investigate
if the commonly used methacrylate HEMA affects protein cysteines.
For this in vitro study, a bronchial epithelial cell line (BEAS-2B) was used as a model. Results showed that
exposure to HEMA (4-10 mM) reduced the cell viability. In addition, HEMA reduced the level of GSH and
S-glutathionylation of at least one protein (MW approx. 42 kDa). These changes were also observed for
concentrations lower than those affecting the cell viability. The results further imply that the observed
protein is β-actin. Although, S-glutathionylation of β-actin is suggested to affect the cytoskeleton by
inhibiting polymerisation of actin, this study could not detect any changes in actin structure after HEMAexposure.
LC-MS analysis of binding between synthetic peptides and HEMA implies that HEMA can bind
to S–glutathionylation site in β-actin. In addition to this possible competitive binding, results obtained by
inhibiting the GSH-synthesis imply that cellular GSH-level also influence the level of β-actin Sglutathionylation | en |
