PUBLICATION
Regeneration of dopaminergic neurons in adult zebrafish depends on immune system activation and differs for distinct populations
- Authors
- Caldwell, L.J., Davies, N.O., Cavone, L., Mysiak, K.S., Semenova, S.A., Panula, P., Armstrong, J.D., Becker, C.G., Becker, T.
- ID
- ZDB-PUB-190406-7
- Date
- 2019
- Source
- The Journal of neuroscience : the official journal of the Society for Neuroscience 39(24): 4694-4713 (Journal)
- Registered Authors
- Becker, Catherina G., Becker, Thomas, Caldwell, Lindsey, Davies, Nick O., Mysiak, Karolina S., Panula, Pertti, Semenova, Svetlana
- Keywords
- none
- MeSH Terms
-
- Aging
- Animals
- Axons/physiology
- Cell Lineage/genetics
- Cell Proliferation
- Diencephalon/cytology
- Diencephalon/physiology
- Dopaminergic Neurons/physiology*
- Female
- Immune System Phenomena/physiology*
- Male
- Microglia/physiology
- Nerve Regeneration/physiology*
- Neural Stem Cells/physiology
- Neurogenesis/genetics
- Neurogenesis/physiology
- Sexual Behavior, Animal/physiology
- Zebrafish/physiology*
- PubMed
- 30948475 Full text @ J. Neurosci.
Citation
Caldwell, L.J., Davies, N.O., Cavone, L., Mysiak, K.S., Semenova, S.A., Panula, P., Armstrong, J.D., Becker, C.G., Becker, T. (2019) Regeneration of dopaminergic neurons in adult zebrafish depends on immune system activation and differs for distinct populations. The Journal of neuroscience : the official journal of the Society for Neuroscience. 39(24):4694-4713.
Abstract
Adult zebrafish, in contrast to mammals, regenerate neurons in their brain, but the extent and variability of this capacity is unclear. Here we ask whether loss of various dopaminergic neuron populations is sufficient to trigger their functional regeneration. Both sexes of zebrafish were analysed. Genetic lineage tracing shows that specific diencephalic ependymo-radial glial progenitor cells (ERGs) give rise to new dopaminergic (Th+) neurons. Ablation elicits an immune response, increased proliferation of ERGs and increased addition of new Th+ neurons in populations that constitutively add new neurons, e.g. diencephalic population 5/6. Inhibiting the immune response attenuates neurogenesis to control levels. Boosting the immune response enhances ERG proliferation, but not addition of Th+ neurons. In contrast, in populations in which constitutive neurogenesis is undetectable, e.g. the posterior tuberculum and locus coeruleus, cell replacement and tissue integration are incomplete and transient. This is associated with loss of spinal Th+ axons, as well as permanent deficits in shoaling and reproductive behaviour. Hence, dopaminergic neuron populations in the adult zebrafish brain show vast differences in regenerative capacity that correlate with constitutive addition of neurons and depend on immune system activation.SIGNIFICANCE STATEMENTDespite the fact that zebrafish show a high propensity to regenerate neurons in the brain, this study reveals that not all types of dopaminergic neurons are functionally regenerated after specific ablation. Hence, in the same adult vertebrate brain, mechanisms of successful and incomplete regeneration can be studied. We identify progenitor cells for dopaminergic neurons and show that activating the immune system promotes proliferation of these cells. However, in some areas of the brain this only leads to insufficient replacement of functionally important dopaminergic neurons that later disappear. Understanding the mechanisms of regeneration zebrafish may inform interventions targeting regeneration of functionally important neurons, such as dopaminergic neurons, from endogenous progenitor cells in non-regenerating mammals.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping