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bioRxiv · 10.1101/2025.04.01.646648

iNeurons are sweet, maybe too sweet? Exploring the impact of media composition on PINK1-dependent mitophagy

Abstract

Parkinsons disease associated proteins PINK1 and Parkin collaboratively regulate stress-induced mitophagy. While in vitro human neuronal cultures are valuable for studying the roles of PINK1 and Parkin in a disease-relevant context, the impact of culture conditions on these processes remains largely underexplored. Here, it is shown that human induced neurons (iNeurons) cultured in N2B27 and BrainPhys medium exhibit distinct PINK1-Parkin dependent mitophagy phenotypes. Specifically, BrainPhys-cultured iNeurons show greater resistance to PINK1-dependent mitophagy initiation, linked to a reduction in glucose availability and reduced PINK1 protein availabilities, leading to decreases in stress-induced and basal mitophagy fluxes. These findings highlight the critical impact of culture conditions on mitophagy dynamics and emphasise the need to account for media-specific differences when using in vitro models to investigate mitophagy mechanisms in human neurons.

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BibTeXRIS

O'Callaghan, B., Melandri, D., Soltic, D., Cosker, K., Soutar, M. P. M., Plun-Favreau, H.. 2025-04-03. iNeurons are sweet, maybe too sweet? Exploring the impact of media composition on PINK1-dependent mitophagy. https://doi.org/10.1101/2025.04.01.646648

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