Cargando…

Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1

Purkinje neuron dendritic degeneration precedes cell loss in cerebellar ataxia, but the basis for dendritic vulnerability in ataxia remains poorly understood. Recent work has suggested that potassium (K(+)) channel dysfunction and consequent spiking abnormalities contribute to Purkinje neuron degene...

Descripción completa

Detalles Bibliográficos
Autores principales: Chopra, Ravi, Bushart, David D., Shakkottai, Vikram G.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5976172/
https://www.ncbi.nlm.nih.gov/pubmed/29847609
http://dx.doi.org/10.1371/journal.pone.0198040
_version_ 1783327128062787584
author Chopra, Ravi
Bushart, David D.
Shakkottai, Vikram G.
author_facet Chopra, Ravi
Bushart, David D.
Shakkottai, Vikram G.
author_sort Chopra, Ravi
collection PubMed
description Purkinje neuron dendritic degeneration precedes cell loss in cerebellar ataxia, but the basis for dendritic vulnerability in ataxia remains poorly understood. Recent work has suggested that potassium (K(+)) channel dysfunction and consequent spiking abnormalities contribute to Purkinje neuron degeneration, but little attention has been paid to how K(+) channel dysfunction impacts dendritic excitability and the role this may play in the degenerative process. We examined the relationship between K(+) channel dysfunction, dendritic excitability and dendritic degeneration in spinocerebellar ataxia type 1 (SCA1). Examination of published RNA sequencing data from SCA1 mice revealed reduced expression of several K(+) channels that are important regulators of excitability in Purkinje neuron dendrites. Patch clamp recordings in Purkinje neurons from SCA1 mice identified increased dendritic excitability in the form of enhanced back-propagation of action potentials and an increased propensity to produce dendritic calcium spikes. Dendritic excitability could be rescued by restoring expression of large-conductance calcium-activated potassium (BK) channels and activating other K(+) channels with baclofen. Importantly, this treatment combination improves motor performance and mitigates dendritic degeneration in SCA1 mice. These results suggest that reduced expression of K(+) channels results in persistently increased dendritic excitability at all stages of disease in SCA1, which in turn may contribute to the dendritic degeneration that precedes cell loss.
format Online
Article
Text
id pubmed-5976172
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-59761722018-06-17 Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1 Chopra, Ravi Bushart, David D. Shakkottai, Vikram G. PLoS One Research Article Purkinje neuron dendritic degeneration precedes cell loss in cerebellar ataxia, but the basis for dendritic vulnerability in ataxia remains poorly understood. Recent work has suggested that potassium (K(+)) channel dysfunction and consequent spiking abnormalities contribute to Purkinje neuron degeneration, but little attention has been paid to how K(+) channel dysfunction impacts dendritic excitability and the role this may play in the degenerative process. We examined the relationship between K(+) channel dysfunction, dendritic excitability and dendritic degeneration in spinocerebellar ataxia type 1 (SCA1). Examination of published RNA sequencing data from SCA1 mice revealed reduced expression of several K(+) channels that are important regulators of excitability in Purkinje neuron dendrites. Patch clamp recordings in Purkinje neurons from SCA1 mice identified increased dendritic excitability in the form of enhanced back-propagation of action potentials and an increased propensity to produce dendritic calcium spikes. Dendritic excitability could be rescued by restoring expression of large-conductance calcium-activated potassium (BK) channels and activating other K(+) channels with baclofen. Importantly, this treatment combination improves motor performance and mitigates dendritic degeneration in SCA1 mice. These results suggest that reduced expression of K(+) channels results in persistently increased dendritic excitability at all stages of disease in SCA1, which in turn may contribute to the dendritic degeneration that precedes cell loss. Public Library of Science 2018-05-30 /pmc/articles/PMC5976172/ /pubmed/29847609 http://dx.doi.org/10.1371/journal.pone.0198040 Text en © 2018 Chopra et al http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Chopra, Ravi
Bushart, David D.
Shakkottai, Vikram G.
Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
title Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
title_full Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
title_fullStr Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
title_full_unstemmed Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
title_short Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
title_sort dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5976172/
https://www.ncbi.nlm.nih.gov/pubmed/29847609
http://dx.doi.org/10.1371/journal.pone.0198040
work_keys_str_mv AT chopraravi dendriticpotassiumchanneldysfunctionmaycontributetodendritedegenerationinspinocerebellarataxiatype1
AT bushartdavidd dendriticpotassiumchanneldysfunctionmaycontributetodendritedegenerationinspinocerebellarataxiatype1
AT shakkottaivikramg dendriticpotassiumchanneldysfunctionmaycontributetodendritedegenerationinspinocerebellarataxiatype1