KIRA7 prevents bleomycin-induced fibrosis.

(A) Chemical structure of KIRA7. (B) Schematic of the KIRA7 prevention regimen. Mice were exposed to saline or bleomycin once, then treated with KIRA7 or vehicle beginning from the time of bleomycin exposure and daily for two weeks after exposure. (C) Western blot of terminal UPR transcription factors XBP1s and ATF4 from mice treated according to the prevention regimen. (D) Quantitative PCR of terminal UPR markers BiP and CHOP from mice treated according to the prevention regimen. Each mouse is represented by a dot, and whiskers denote group mean +/- SEM. (E) Hematoxylin and eosin stained sections from mice treated according to the prevention regimen, at low magnification (top) and high magnification (bottom). (F) Representative high-magnification sections stained with picrosirius red, from mice treated as in (E), under unpolarized (top) and polarized light (bottom). (G) Quantification of picrosirius red stained fibrillar collagen from (F). Each mouse is represented by a dot and whiskers denote group mean +/- SEM. (H) Markers of fibrosis (lung weight, hydroxyproline content, collagen 1A1 mRNA, and fibronectin mRNA) from mice treated according to the prevention regimen. Each mouse is represented by a dot, and whiskers denote group mean +/- SEM. P values: *<0.05, **<0.01, ***<0.001.