Figure 1

PPARγ expression and activity are decreased in BAL from MWCNT-instilled wild-type C57Bl/6 mice. (A) BAL cell mRNA samples from MWCNT or sham-treated mice (n=4/group) were analyzed by quantitative PCR. PPARγ mRNA was significantly decreased (p = 0.003) 60 days post MWCNT instillation. Immunocytochemistry of alveolar macrophages collected by cytospins demonstrated decreased nuclear staining for PPARγ protein at 60 days after MWCNT instillation (C) compared to sham controls (B). (Nuclei were counterstained with propidium iodide). (D) Quantification of PPARγ fluorescence intensity of alveolar macrophages in immunostained cytospins (n=99 cells/slide) indicated MWCNT exposure significantly reduced PPARγ expression (n=5/group). (E) PPARγ binding activity was reduced in alveolar macrophages of MWCNT-treated mice (n=3/group) as measured by ELISA.