In Vivo Imaging of Senescent Vascular Cells in Atherosclerotic Mice Using a β‑Galactosidase-Activatable Nanoprobe

Senescence-associated diseases have severely diminished the quality of life and health of patients. However, a sensitive assay of these diseases remains limited due to a lack of straightforward methods. Considering that senescence-associated β-galactosidase (SA-β-Gal) is overexpressed in senescent cells, the detection of SA-β-Gal in senescent cells and tissues might be a feasible strategy for the early diagnosis of SA diseases. In this study, a β-galactosidase-activatable nanoprobe BOD-L-βGal-NPs was developed for the imaging of senescent cells and vasculature in atherosclerotic mice via real-time monitoring of β-Gal. BOD-L-βGal-NPs was fabricated by encapsulating a newly designed NIR ratiometric probe BOD-L-βGal within a poly­(lactic-co-glycolic) acid (PLGA) core. Nanoprobe BOD-L-βGal-NPs showed good accumulation in arteries, thus successfully visualizing senescent cells and vasculature in atherosclerotic mice by tail vein injection. Our findings indicated that nanoprobe BOD-L-βGal-NPs holds great potential for the early diagnosis and therapy of atherosclerosis and other aging-associated diseases.