Neurovascular dysfunction in many neurodegenerative diseases, such as Alzheimer’s disease (AD), reduces blood flow to affected brain areas and causes neuronal dysfunction and loss. A new optical imaging technique is developed to activate astrocytes in live animal models in order to investigate the increase of local cerebral blood flow as a potential therapeutic strategy for AD. The technique uses fluorescent labeling of vasculature and astrocytes coupled with intravital 2-photon microscopy to visualize the astrocyte-vasculature interactions in live animals. Using femtosecond laser stimulation, calcium uncaging is applied to specifically target and activate astrocytes in vivo with high spatial and temporal resolutions. Intravital 2-photon microscopy imaging was employed to demonstrate that single endfoot optical activation around an arteriole induced a 25% increase in arteriole diameter, which in turn increased cerebral local blood flow in down-stream capillaries. This quantitative result indicates the potential of using optical activation of astrocytes in afflicted brain areas of neurodegeneration to restore normal neurovascular functions.

Date Published: 8 March 2013
PDF: 9 pages
Proc. SPIE 8565, Photonic Therapeutics and Diagnostics IX, 85655K (8 March 2013); doi: 10.1117/12.2004712

Published in SPIE Proceedings Vol. 8565:
Photonic Therapeutics and Diagnostics IX
Andreas Mandelis; Brian Jet-Fei Wong; Anita Mahadevan-Jansen; Henry Hirschberg M.D.; Hyun Wook Kang; Nikiforos Kollias; Melissa J. Suter; Kenton W. Gregory M.D.; Guillermo J. Tearney M.D.; Stephen Lam; Bernard Choi; Steen J. Madsen; Bodo E. Knudsen M.D.; E. Duco Jansen; Justus F. Ilgner M.D.; Haishan Zeng; Matthew Brenner; Laura Marcu, Editor(s)