Development of dual functional SPECT/fluorescent probes for imaging cerebral beta-amyloid plaques
Masahiro Ono1, Manami Ishikawa, Hiroyuki Kimura
1Kyoto University, Sakyo-ku, Japan. ono@pharm.kyoto-u.ac.jp
Abstract:
The imaging of beta-amyloid (Abeta) aggregates in the brain may lead to the early detection of Alzheimer's disease (AD) and monitoring of the progression and effectiveness of treatment. The purpose of this study was to develop dual modality SPECT and fluorescent probes based on boron dipyrromethane (BODIPY) as a core structure. We designed and synthesized an (125)I-labeled derivative of BODIPY (BODIPY7). BODIPY7 had a K(i) value of 108nM for Abeta(1-42) aggregates and exhibited peaks of absorption/emission at 606/613nm. It detected Abeta plaques in sections of brain tissue from an animal model of AD and displayed low uptake in the brain and high uptake in the liver in normal mice. Although additional modifications of the BODIPY scaffold are necessary to improve brain uptake, these results should aid the development of dual functional SPECT/fluorescent probes for the imaging of Abeta plaques in the brain.
