Using redox-sensitive mitochondrial cytochrome Raman bands for label-free detection of mitochondrial dysfunctionElectronic supplementary information (ESI) available. See DOI: 10.1039/c8an02213e

• Main Authors: Morimoto, Takeshi, Chiu, Liang-da, Kanda, Hiroyuki, Kawagoe, Hiroyuki, Ozawa, Takeaki, Nakamura, Makoto, Nishida, Kohji, Fujita, Katsumasa, Fujikado, Takashi
• Format: Journal Article
• Published: 08.04.2019
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/c8an02213e

Mitochondrial activity is a widely used criterion to judge the metabolic condition of a living specimen. Numerous methods have been developed for related analyses, including the detection of O 2 consumption, trans-membrane potential, and ATP production. In this study, we demonstrate that the redox state of cytochromes can serve as a sensitive mitochondrial activity indicator in glutamate-stressed neuronal cells. Mitochondrial dysfunction was detected by Raman imaging as early as 30 min after glutamate-stress induction. By comparing this result with other commonly used mitochondrial function assays, we found Raman imaging has a similar sensitivity to ATP production and trans-membrane potential assays. Other viability tests, such as MTT assay and ROS production tests, showed a slower response than our method. A thorough understanding of cytochrome dynamics with our new method will help establish Raman spectroscopy as a competitive clinical diagnosis tool for neurodegenerative diseases involving mitochondrial dysfunction. We present a label-free imaging technique that detects mitochondrial activities with a sub-cellular spatial resolution.