Imaging epigenetic regulation by histone deacetylases in the brain using PET/MRI with ¹⁸F-FAHA.

Epigenetic modifications mediated by histone deacetylases (HDACs) play important roles in the mechanisms of different neurologic diseases and HDAC inhibitors (HDACIs) have shown promise in therapy. However, pharmacodynamic profiles of many HDACIs in the brain remain largely unknown due to the lack of validated methods for noninvasive imaging of HDAC expression-activity. In this study, dynamic PET/CT imaging was performed in 4 rhesus macaques using [(18)F]FAHA, a novel HDAC substrate, and [(18)F]fluoroacetate, the major radio-metabolite of [(18)F]FAHA, and fused with corresponding MR images of the brain.