Identification of Celecoxib targeted proteins using label-free thermal
proteome profiling on rat hippocampus
Abstract
Celecoxib or Celebrex, an NSAID (non-steroidal anti-inflammatory drug),
is one of the most common medicines for treating inflammatory diseases.
Recently, it has been shown that celecoxib is associated with
implications in complex diseases such as Alzheimer’s disease and cancer,
as well as with cardiovascular risk assessment and toxicity, suggesting
that celecoxib may affect multiple unknown targets. In this project, we
detected targets of celecoxib within the nervous system using a
label-free TPP (Thermal Proteome Profiling) method. First, proteins of
the rat hippocampus were treated with multiple drug concentrations and
temperatures. Next, we separated the soluble proteins from the denatured
and sedimented total protein load by ultracentrifugation. Subsequently,
the soluble proteins were analyzed by nano-liquid chromatography-mass
spectrometry to determine the identity of the celecoxib targeted
proteins based on structural changes by thermal stability variation of
targeted proteins towards higher solubility in the higher temperatures.
In the analysis of the soluble protein extract at 67 centigrade, 44
proteins were uniquely detected in drug-treated samples out of all 478
identified proteins at this temperature. Rab4a, one out of these 44
proteins, has previously been reported as one of the celecoxib
off-targets in the rat CNS. Furthermore, we provide more molecular
details through biomedical enrichment analysis to explore the potential
role of all detected proteins in the biological systems. We show that
the determined proteins play a role in the signaling pathways related to
neurodegenerative disease - and cancer pathways. Finally, we fill out
molecular supporting evidence for using celecoxib towards the drug
repurposing approach by exploring drug targets.