Proteomic profiling reveals mitochondrial metabolic alterations in dexamethasone-induced neuronal differentiation

ObjectiveAs an in vitro model of catecholaminergic neurons, Cath.a Differentiated cells or CAD cells have been selected because of their direct origin in the mouse CNS and their ability to undergo inducible differentiation. Dexamethasone (DEX), a glucocorticoid receptor agonist, generates postmitotic and neurite-bearing CAD cells. Although the morphological differentiation of CAD cells induced by DEX has been well characterized, a comprehensive understanding of its proteomic profile and underlying pathways remains limited. Neuronal differentiation involves substantial remodeling of mitochondrial metabolic programs. However, the relationship between DEX-induced neuronal differentiation in CAD cells and mitochondrial metabolic state remains incompletely understood.MethodsIn this study, we applied a label-free quantitative SWATH-MS proteomic approach to investigate the protein expression in CAD cells upon differentiation.ResultsThe results of the proteomic analysis of 1,114 proteins associated with various GO terms, including neuronal differentiation and characteristics of brain-derived CAD cells, are shown. The data revealed the upregulation of proteins involved in mitochondria-associated metabolism and oxidative phosphorylation in DEX-differentiated cells compared with those in dividing cells, highlighting the role of mitochondrial metabolic changes during the neuronal differentiation of CAD cells. In addition, we identified proteins that were commonly expressed between the two neuronal differentiating protocols. A shared set of proteins involves electron transport, metabolic pathways, and DNA repair.ConclusionsThis study first highlights the proteomic signature and elucidates the key altered molecular pathways underlying DEX-induced neuronal differentiation in CAD cells.