Insulin signaling promotes neurogenesis in the brain of adult zebrafish.
Laura GenceDanielle FernezelianOlivier MeilhacSepand RastegarJean-Loup BascandsNicolas DiotelPublished in: The Journal of comparative neurology (2023)
Insulin is a peptide hormone that plays a central role in the regulation of circulating blood glucose in vertebrates, including zebrafish. Increasing evidence has demonstrated the important role of insulin in many brain functions. In zebrafish, two insulin receptor genes (insra and insrb) have been identified. However, their biodistribution in the adult brain as well as their cell-specific expression pattern has not been well described. Using gene expression analysis, in situ hybridization and transgenic fish, we confirmed the expression of insra, insrb, and irs1 (insulin receptor substrate 1, the downstream effector of insulin receptor) in the brain of adult zebrafish and characterized their specific expression in neurons and neural stem cells (radial glia). After demonstrating that intracerebroventricular (ICV) injection resulted in the diffusion of the injected solution within the ventricular system, we analyzed the effect of insulin ICV injection on neurogenesis. We showed that insulin promotes ventricular cell proliferation 24 h postinjection. This neurogenic effect appeared to be independent of neuroinflammatory processes. Also, after a mechanical telencephalic stab-wound injury, we highlighted the overexpression of irs1 gene 5 days postlesion notably in the ventricular zone where radial glial cells (RGCs) are localized, suggesting key roles of insulin signaling in regenerative processes. Finally, our results reinforced the expression of insulin-related proteins in the brain of adult zebrafish, highlighting the potential role of insulin signaling on neurogenesis.
Keyphrases
- type diabetes
- glycemic control
- blood glucose
- poor prognosis
- cell proliferation
- resting state
- heart failure
- stem cells
- white matter
- neural stem cells
- cerebral ischemia
- spinal cord injury
- mesenchymal stem cells
- blood pressure
- genome wide
- left ventricular
- spinal cord
- copy number
- binding protein
- functional connectivity
- climate change
- weight loss
- skeletal muscle
- young adults
- long non coding rna
- brain injury
- regulatory t cells
- risk assessment
- single cell
- genome wide identification
- childhood cancer
- blood brain barrier
- bone marrow
- transcription factor
- induced apoptosis
- signaling pathway
- drug induced
- catheter ablation
- neuropathic pain
- cell cycle arrest