Hematopoietic-derived cells as potential neural precursors in adult neurogenesis
2012 (English)Conference paper (Other academic)
Adult neurogenesis occurs in many vertebrate and invertebrate species, including decapod crustaceans. In the crayfish Procambarus clarkii, new neurons are integrated into interneuronal cell clusters innervating the olfactory and accessory lobes. The 1st-generation precursor cells reside in a niche, where they divide symmetrically; both daughter cells migrate along streams to proliferation zones in the cell clusters, where additional divisions and neuronal differentiation occur. Although divisions of existing niche cells do not replenish the niche, niche cell numbers increase with age. Niche precursor cells must, therefore, originate from an extrinsic source. It has been hypothesized that circulating stem cells of possible hematopoietic origin migrate into the niche from the hemolymph. Previous studies in crayfish have suggested that circulating semi-granular cells are attracted to the niche (Benton et al., 2011). Astakine-1, a prokineticin, has been shown to promote the differentiation and release of semi-granular cells from the hematopoietic tissue (Lin and Soderhall, 2011). Astakine-1 injection also results in increased numbers of cells in the neurogenic niche. In this study, hematopoietic tissue (HPT) was ablated in order to better define the relationship between the hematopoietic system and adult neurogenesis. The most dorsal regions of HPT were removed, leaving some ventral blood-generating tissue. Ten days post-surgery, ablated animals had fewer niche cells relative to sham controls (p<0.001). There were no differences in numbers of dividing (BrdU-labeled) cells in the niche or cell clusters where the adult-born neurons reside. If astakine-1 is injected into HPT-ablated animals 48 hours prior to sacrifice, this deficit in niche cells is ameliorated. A strong positive correlation was found between the numbers of circulating hemocytes immediately before sacrifice and the numbers of cells in the neurogenic niche. Therefore, following HPT ablation the numbers of niche cells are reduced, but can be restored by astakine-1 injection after ablation. Taken together, these data demonstrate a close and dynamic relationship between hematopoiesis and adult neurogenesis in the crayfish brain.
Place, publisher, year, edition, pages
2012. 427.01/A47- p.
IdentifiersURN: urn:nbn:se:uu:diva-189799OAI: oai:DiVA.org:uu-189799DiVA: diva2:582318
42nd Annual Meeting of the Society for Neuroscience .New Orleans, LA, October 13 -17, 2012
FunderSwedish Research Council, 621-2011-4797