title: Quantification of the Metabolic State in Cell-Model of Parkinson's Disease by Fluorescence Lifetime Imaging Microscopy.
abstract: Intracellular endogenous fluorescent co-enzymes, reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD), play a pivotal role in cellular metabolism; quantitative assessment of their presence in living cells can be exploited to monitor cellular energetics in Parkinson's disease (PD), a neurodegenerative disorder. Here, we applied two-photon fluorescence lifetime imaging microscopy (2P-FLIM) to noninvasively measure the fluorescence lifetime components of NADH and FAD, and their relative contributions in MPP(+) (1-methyl-4-phenylpyridinium) treated neuronal cells, derived from PC12 cells treated with nerve growth factor (NGF), to mimic PD conditions. A systematic FLIM data analysis showed a statistically significant (p < 0.001) decrease in the fluorescence lifetime of both free and protein-bound NADH, as well as free and protein-bound FAD in MPP(+) treated cells. On the relative contributions of the free and protein-bound NADH and FAD to the life time, however, both the free NADH contribution and the corresponding protein-bound FAD contribution increase significantly (p < 0.001) in MPP(+) treated cells, compared to control cells. These results, which indicate a shift in energy production in the MPP(+) treated cells from oxidative phosphorylation towards anaerobic glycolysis, can potentially be used as cellular metabolic metrics to assess the condition of PD at the cellular level.
authors.affiliation: Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan 11221, ROC.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Chakraborty
authors.affiliation: Program in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan 11529, ROC.|Institue of Brain Science, National Yang-Ming University, Taipei, Taiwan 11221, ROC.
authors.forename: Fang-Shin
authors.initials: FS
authors.lastname: Nian
authors.affiliation: Institue of Brain Science, National Yang-Ming University, Taipei, Taiwan 11221, ROC.|Biophotonics and Molecular Imaging Research Center, National Yang-Ming University, Taipei, Taiwan 11221, ROC.
authors.forename: Jin-Wu
authors.initials: JW
authors.lastname: Tsai
authors.affiliation: Biophotonics and Molecular Imaging Research Center, National Yang-Ming University, Taipei, Taiwan 11221, ROC.|Department of Physics, National Dong Hwa University, Hualien, Taiwan 97401, ROC.
authors.forename: Artashes
authors.initials: A
authors.lastname: Karmenyan
authors.affiliation: Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan 11221, ROC.|Biophotonics and Molecular Imaging Research Center, National Yang-Ming University, Taipei, Taiwan 11221, ROC.
authors.forename: Arthur
authors.initials: A
authors.lastname: Chiou
mesh_terms: D000818:Animals; D004734:Energy Metabolism / Q000187:drug effects; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D055432:Metabolomics / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods; D008954:Models, Biological; D009243:NAD / Q000378:metabolism; D020932:Nerve Growth Factor / Q000494:pharmacology; D016716:PC12 Cells; D010300:Parkinson Disease / Q000378:metabolism; D051381:Rats
chemical_list: D009243:NAD; D005182:Flavin-Adenine Dinucleotide; D020932:Nerve Growth Factor