Spermidine treatment: induction of autophagy but also apoptosis?

Maxinne Watchon, Amanda L. Wright, Holly I. Ahel, Katherine J. Robinson, Stuart K. Plenderleith, Andrea Kuriakose, Kristy C. Yuan, Angela S. Laird*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Downloads (Pure)

Abstract

Machado-Joseph disease (MJD), also known as spinocerebellar ataxia type 3, is a fatal neurodegenerative disease that causes loss of balance and motor co-ordination, eventually leading to paralysis. It is caused by the autosomal dominant inheritance of a long CAG trinucleotide repeat sequence within the ATXN3 gene, encoding for an expanded polyglutamine (polyQ) repeat sequence within the ataxin-3 protein. Ataxin-3 containing an expanded polyQ repeat is known to be highly prone to intraneuronal aggregation, and previous studies have demonstrated that protein quality control pathways, such as autophagy, are impaired in MJD patients and animal models of the disease. In this study, we tested the therapeutic potential of spermidine on zebrafish and rodent models of MJD to determine its capacity to induce autophagy and improve functional output. Spermidine treatment of transgenic MJD zebrafish induced autophagy and resulted in increased distances swum by the MJD zebrafish. Interestingly, treatment of the CMVMJD135 mouse model of MJD with spermidine added to drinking water did not produce any improvement in motor behaviour assays, neurological testing or neuropathology. In fact, wild type mice treated with spermidine were found to have decreased rotarod performance when compared to control animals. Immunoblot analysis of protein lysates extracted from mouse cerebellar tissue found little differences between the groups, except for an increased level of phospho-ULK1 in spermidine treated animals, suggesting that autophagy was indeed induced. As we detected decreased motor performance in wild type mice following treatment with spermidine, we conducted follow up studies into the effects of spermidine treatment in zebrafish. Interestingly, we found that in addition to inducing autophagy, spermidine treatment also induced apoptosis, particularly in wild type zebrafish. These findings suggest that spermidine treatment may not be therapeutically beneficial for the treatment of MJD, and in fact warrants caution due to the potential negative side effects caused by induction of apoptosis.

Original languageEnglish
Article number15
Pages (from-to)1-15
Number of pages15
JournalMolecular Brain
Volume17
Issue number1
DOIs
Publication statusPublished - 5 Mar 2024

Bibliographical note

Crown Copyright 2024. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.

Keywords

  • Autophagy
  • Machado-Joseph disease
  • Neurodegeneration
  • PolyQ
  • Spinocerebellar ataxia type 3
  • Trinucleotide repeat disease
  • Zebrafish

Fingerprint

Dive into the research topics of 'Spermidine treatment: induction of autophagy but also apoptosis?'. Together they form a unique fingerprint.

Cite this