Figure 7.

Airborne particulate matter causes increased levels of two oxidized PAPC derivatives in BAL fluid of PM_2.5 exposed mice. Lipid extracts from BAL fluid of TLR4^wt and TLR4^d mice exposed for 20 weeks to FA or PM_2.5 were analyzed by HPLC with positive electrospray ionization mass-spectrometry operating in multiple reaction monitoring mode. Parent PAPC and oxidized derivatives (POVPC and PGPC) ion pairs were monitored by their characteristic retention time and daughter ions. Corresponding chromatograms were post-processed by extraction of POVPC and PGPC ions for quantitative analysis. Representative LC-MS chromatograms are shown for (A) TLR4^wt FA, (B) TLR4^wt PM_2.5, (C) TLR4^d FA, (D) TLR4^d PM_2.5. (E) Chemical structures of monitored phospholipids. Quantitative analysis of levels of (F) POVPC and (G) PGPC against PAPC with an exaggerated level of oxidation in the PM_2.5 exposed mice over 20 weeks. In-vitro incubation of PAPC in the presence of PM_2.5 or with PBS was performed in time-dependent manner followed by quantification of levels of (H) POVPC and (I) PGPC by LC/MS-MS. BAL fluid of 5 mice per group were pooled for these experiments with extraction of the lipid content. The amount of oxidized phospholipid is set in ratio to non-oxidized phospholipid in order to compare the different groups.