In vivo brain imaging of mitochondrial Ca in neurodegenerative diseases with multiphoton microscopy.

Mitochondria are involved in a large number of essential roles related to neuronal function. Ca handling by mitochondria is critical for many of these functions, including energy production and cellular fate. Conversely, mitochondrial Ca mishandling has been related to a variety of neurodegenerative diseases. Investigating mitochondrial Ca dynamics is essential for advancing our understanding of the role of intracellular mitochondrial Ca signals in physiology and pathology. Improved Ca indicators, and the ability to target them to different cells and compartments, have emerged as useful tools for analysis of Ca signals in living organisms. Combined with state-of-the-art techniques such as multiphoton microscopy, they allow for the study of mitochondrial Ca dynamics in vivo in mouse models of the disease. Here, we provide an overview of the Ca transporters/ion channels in mitochondrial membranes, and the involvement of mitochondrial Ca in neurodegenerative diseases followed by a summary of the main tools available to evaluate mitochondrial Ca dynamics in vivo using the aforementioned technique.