Aging Differentially Affects Axonal Autophagosome Formation and Maturation

Authors

Heather Tsong
Erika Lf Holzbaur
Andrea Kh Stavoe

Publication Date

12-1-2023

Journal

Autophagy

Abstract

Misregulation of neuronal macroautophagy/autophagy has been implicated in age-related neurodegenerative diseases. We compared autophagosome formation and maturation in primary murine neurons during development and through aging to elucidate how aging affects neuronal autophagy. We observed an age-related decrease in the rate of autophagosome formation leading to a significant decrease in the density of autophagosomes along the axon. Next, we identified a surprising increase in the maturation of autophagic vesicles in neurons from aged mice. While we did not detect notable changes in endolysosomal content in the distal axon during early aging, we did observe a significant loss of acidified vesicles in the distal axon during late aging. Interestingly, we found that autophagic vesicles were transported more efficiently in neurons from adult mice than in neurons from young mice. This efficient transport of autophagic vesicles in both the distal and proximal axon is maintained in neurons during early aging, but is lost during late aging. Our data indicate that early aging does not negatively impact autophagic vesicle transport nor the later stages of autophagy. However, alterations in autophagic vesicle transport efficiency during late aging reveal that aging differentially impacts distinct aspects of neuronal autophagy.

Keywords

Mice, Animals, Autophagosomes, Autophagy, Macroautophagy, Mitogen-Activated Protein Kinase 8, Axons, Lysosomes, Aging, axonal transport, lysosome, microtubule transport, neuron

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Associated Data

PMID: 37464898