Imaging pulmonary fibrosis with a practical probe for the detection of peroxynitrite in living cells and mice

Idiopathic pulmonary fibrosis (IPF) is a frequent chronic trouble, during which the fibrogenic process was associated to the chronic inflammation and oxidative stress, especially peroxynitrite. In this work, we intended to image the pulmonary fibrosis with a practical probe, YXP, for the detection of peroxynitrite. The probe showed the emission at 535 nm when being excited at 397 nm. The fluorescence quantum yield was calculated as 0.31 and the limit of detection was determined as 0.81 mu M with a linear range of 2-10 mu M. The response time was within 300 s, and the fluorescence intensity was steady over 48 h and within the range of 6-10. With high selectivity and non-interference, YXP was applied in the applications in living BEAS cells from human lung and in pulmonary fibrosis model in mice. In living cells, YXP could exhibit dose-dependent response towards ONOO- with steady signal output, and reflect the fluctuation of endogenous ONOO- in the physiological procedures. In the successfully constructed pulmonary fibrosis model, YXP could hint the development of the damage by the detection of peroxynitrite. The findings and applications in this work might provide useful information for the early diagnosis of IPF.