Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.27.353862v1?rss=1 Authors: Ni, R., Villois, A., Dean-Ben, X. L., Chen, Z., Vaas, M., Stavrakis, S., Shi, G., deMello, A., Ran, C., Razansky, D., Arosio, P., Klohs, J. Abstract: The abnormal deposition of fibrillar beta-amyloid (Ab) deposits in the brain is one of the major histopathological hallmarks of Alzheimers disease (AD). Here we characterize curcumin-derivative CRANAD-2 for multi-spectral optoacoustic tomography (MSOT) and fluorescence imaging of brain Ab; deposits in the arcAb; mouse model of AD cerebral amyloidosis. CRANAD-2 shows a specific and quantitative detection of Ab; fibrils in vitro, even in complex mixtures, and it is capable to distinguish between monomeric and fibrillar forms of Ab;. In vivo epifluorescence and MSOT after intravenous CRANAD-2 administration demonstrated higher retention in arcAb; compared to non-transgenic littermate mice. Immunohistochemistry showed co-localization of CRANAD-2 and Ab; deposits in arcAb; mouse brain sections, thus verifying the specificity of the probe. In conclusion, we demonstrate suitability of CRANAD-2 for fluorescence- and MSOT-based detection of Ab; deposits in animal models of AD pathology, which facilitates mechanistic studies and the monitoring of putative treatments targeting Ab; deposits. Copy rights belong to original authors. Visit the link for more info