MWCNTs of varying size lead to DNA methylation changes that correspond to lung inflammation and injury in a mouse model

Diversity in physico-chemical properties of engineered multi-walled carbon nanotubes (MWCNT) increases the complexity involved in interpreting toxicity studies of these materials. Studies indicate that epigenetic changes could be at least partially involved in MWCNT-induced pro- inflammatory and fibrotic lung pathology. Therefore, we examined distinct methylation changes in response to MWCNT of varied sizes in order to identify potential epigenetic biomarkers of MWCNT exposure and disease progression. C57BL/6 mice were exposed via oropharyngeal instillation to a single dose (50 g) to one of three differently sized MWCNTs: “Narrow Short” (NS), “Wide Short” (WS), and “Narrow Long” (NL). Vehicle-treated control mice received dispersion media (DM) only. Whole lung lavage fluid (LLF) and lung tissue were collected 24 hours and 7 days post-exposure to evaluate pro-inflammatory cytokines, epigenetic, or histological responses at acute and sub-chronic intervals, respectively. Luminometric methylation assay and p...