Serum Biomarkers Reveal Long-term Cardiac Injury in Isoproterenol-treated African Green Monkeys

The assessment of cardiac toxicity
is a major challenge in both
drug development and clinical trials, and numerous marketed pharmaceuticals
have been removed from the market due to unpredicted cardiac effects.
Serum troponins are widely used indicators of cardiac injury; however,
they are short-lived and have not been validated in preclinical animal
models. In this study, we have used filter-aided sample preparation
(FASP) and tandem mass tag (TMT) labeling to investigate serum protein
alterations in isoproterenol-treated African green monkeys. Our results
showed that the combination of FASP and TMT labeling provided highly
reproducible and efficient sample preparation, which enables us to
identify and quantify serum proteins with high confidence. We focused
on the proteins that exhibit long-term alteration upon isoproterenol
injection and discovered nine proteins exhibiting significant changes
at 48 and 72 h postdosing. We further chose three proteins, serum
amyloid A (SAA), frutose biphosphate aldolase A (FBAA), and fetuin
A, for validation using enzyme-linked immunosorbent assay (ELISA).
The serum concentration of SAA showed a ∼50 fold increase,
while concentration of FBAA and fetuin A exhibited a significant decrease
accompanying isoproterenol-induced cardiotoxicity. This work provides
valuable insights for multimarker evaluation of long-term cardiac
injury.