Novel AIE Probe for In Situ Imaging of Protein Sulfonation to Assess Cigarette Smoke-Induced Inflammatory Damage.

Abstract

Cysteine sulfonic acid, a product of protein oxidative damage, is an important sign by which the body and cells sense oxidative stress. Cigarette smoke (CS) can trigger inflammatory reactions in humans that lead to higher levels of oxidative stress and reactive oxygen species (ROS) in the body. Available evidence indicates a possible relationship between protein oxidative damage and cigarette smoke, which is poorly understood due to the limitations of analytical techniques. Herein, we developed a donor-acceptor structured aggregation-induced emission (AIE) fluorescence probe H-1, which exhibited excellent optical properties for the highly sensitive and specific detection of sulfonic acid biomacromolecules. The probe could be easily synthesized by click chemistry conjugating triazole heterocycles onto a triphenylamine fluorophore, followed by a cationization reaction. Due to low cytotoxity, the probe was successfully applied for in situ imaging of intracellular protein sulfonation, achieving visualization of protein sulfonation in cigarette smoke stimulation-induced inflammatory RAW264.7 cell models. Moreover, an immunofluorescence study of the aorta and lung revealed that significant blue fluorescence signals could be observed only in CS-stimulated vascular. It indicated that CS-stimulated vascular sulfonation injury can be monitored using H-1. This study will provide an efficient method for revealing CS-induced oxidative damage-relevant diseases.