| 1. |
- Bhardwaj, R. D., et al.
(författare)
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Neocortical neurogenesis in humans is restricted to development.
- 2006
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 103:33, s. 12564-8
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Tidskriftsartikel (refereegranskat)abstract
- Stem cells generate neurons in discrete regions in the postnatal mammalian brain. However, the extent of neurogenesis in the adult human brain has been difficult to establish. We have taken advantage of the integration of (14)C, generated by nuclear bomb tests during the Cold War, in DNA to establish the age of neurons in the major areas of the human cerebral neocortex. Together with the analysis of the neocortex from patients who received BrdU, which integrates in the DNA of dividing cells, our results demonstrate that, whereas nonneuronal cells turn over, neurons in the human cerebral neocortex are not generated in adulthood at detectable levels but are generated perinatally.
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| 2. |
- van den Berge, Simone A, et al.
(författare)
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Longterm quiescent cells in the aged human subventricular neurogenic system specifically express GFAP-delta.
- 2010
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Ingår i: Aging cell. - : Wiley. - 1474-9726 .- 1474-9718. ; 9:3, s. 313-326
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Tidskriftsartikel (refereegranskat)abstract
- Summary A main neurogenic niche in the adult human brain is the subventricular zone (SVZ). Recent data suggest that the progenitors that are born in the human SVZ migrate via the rostral migratory stream (RMS) towards the olfactory bulb (OB), similar to what has been observed in other mammals. A subpopulation of astrocytes in the SVZ specifically expresses an assembly-compromised isoform of the intermediate filament protein glial fibrillary acidic protein (GFAP-delta). To further define the phenotype of these GFAP-delta expressing cells and to determine whether these cells are present throughout the human subventricular neurogenic system, we analysed SVZ, RMS and OB sections of 14 aged brain donors (ages 74-93). GFAP-delta was expressed in the SVZ along the ventricle, in the RMS and in the OB. The GFAP-delta cells in the SVZ co-expressed the neural stem cell (NSC) marker nestin and the cell proliferation markers proliferating cell nuclear antigen (PCNA) and Mcm2. Furthermore, BrdU retention was found in GFAP-delta positive cells in the SVZ. In the RMS, GFAP-delta was expressed in the glial net surrounding the neuroblasts. In the OB, GFAP-delta positive cells co-expressed PCNA. We also showed that GFAP-delta cells are present in neurosphere cultures that were derived from SVZ precursors, isolated postmortem from four brain donors (ages 63-91). Taken together, our findings show that GFAP-delta is expressed in an astrocytic subpopulation in the SVZ, the RMS and the OB. Importantly, we provide the first evidence that GFAP-delta is specifically expressed in longterm quiescent cells in the human SVZ, which are reminiscent of NSCs.
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| 3. |
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| 4. |
- Curtis, Maurice A, et al.
(författare)
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Human neuroblasts migrate to the olfactory bulb via a lateral ventricular extension.
- 2007
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Ingår i: Science (New York, N.Y.). - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 315:5816, s. 1243-9
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Tidskriftsartikel (refereegranskat)abstract
- The rostral migratory stream (RMS) is the main pathway by which newly born subventricular zone cells reach the olfactory bulb (OB) in rodents. However, the RMS in the adult human brain has been elusive. We demonstrate the presence of a human RMS, which is unexpectedly organized around a lateral ventricular extension reaching the OB, and illustrate the neuroblasts in it. The RMS ensheathing the lateral olfactory ventricular extension, as seen by magnetic resonance imaging, cell-specific markers, and electron microscopy, contains progenitor cells with migratory characteristics and cells that incorporate 5-bromo-2'-deoxyuridine and become mature neurons in the OB.
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| 5. |
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| 6. |
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| 7. |
- Curtis, Maurice A, et al.
(författare)
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The rostral migratory stream and olfactory system: smell, disease and slippery cells.
- 2009
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Ingår i: Progress in brain research. - 1875-7855. ; 175, s. 33-42
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Tidskriftsartikel (refereegranskat)abstract
- In the mammalian brain, olfaction is an important sense that is used to detect odors of different kinds that can warn of off food, to produce a mothering instinct in a flock or group of animals, and to warn of danger such as fire or poison. The olfactory system is made up of a long-distance rostral migratory stream that arises from the subventricular zone in the wall of the lateral ventricle, mainly comprises neuroblasts, and stretches all the way through the basal forebrain to terminate in the olfactory bulb. The olfactory bulb receives a constant supply of new neurons that allow ongoing integration of new and different smells, and these are integrated into either the granule cell layer or the periglomerular layer. The continuous turnover of neurons in the olfactory bulb allows us to study the proliferation, migration, and differentiation of neurons and their application in therapies for neurodegenerative diseases. In this chapter, we will examine the notion that the olfactory system might be the route of entry for factors that cause or contribute to neurodegeneration in the central nervous system. We will also discuss the enzymes that may be involved in the addition of polysialic acid to neural cell adhesion molecule, which is vital for allowing the neuroblasts to move through the rostral migratory stream. Finally, we will discuss a possible role of endosialidases for removing polysialic acid from neural cell adhesion molecules, which causes neuroblasts to stop migrating and terminally differentiate into olfactory bulb interneurons.
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| 8. |
- Kam, Monica, et al.
(författare)
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The cellular composition and morphological organization of the rostral migratory stream in the adult human brain.
- 2009
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Ingår i: Journal of chemical neuroanatomy. - : Elsevier BV. - 1873-6300 .- 0891-0618. ; 37:3, s. 196-205
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Tidskriftsartikel (refereegranskat)abstract
- The rostral migratory stream (RMS) is the major pathway by which progenitor cells migrate from the subventricular zone (SVZ) to the olfactory bulb (OB) in rodents, rabbits and primates. However, the existence of an RMS within the adult human brain has been elusive. Immunohistochemical studies utilising cell-type specific markers for early progenitor cells (CD133), proliferating cells (PCNA), astrocytes and type B cells (GFAP) and migrating neuroblasts (PSA-NCAM), reveal that the adult human RMS is organized into layers containing glial cells, proliferating cells and neuroblasts. In addition, the RMS is arranged around a remnant of the ventricular cavity that extends from the SVZ to the OB as seen by immunohistological staining analysis and electron microscopy, showing the presence of basal bodies and a typical 9+2 arrangement of tubulin in tufts of cilia from all levels of the RMS. Overall, these findings suggest that a pathway of migratory progenitor cells similar to that seen in other mammals is present within the adult human brain and that this pathway could provide for neurogenesis in the human forebrain. These findings contribute to the scientific understanding of adult neurogenesis and establish the detailed cytoarchitecture of this novel neurogenic niche in the human brain.
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| 9. |
- Landgren, Henrik, 1978, et al.
(författare)
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Locating and Labeling Neural Stem Cells in the Brain
- 2011
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Ingår i: JOURNAL OF CELLULAR PHYSIOLOGY. - 0021-9541. ; 226:1, s. 1-7
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Forskningsöversikt (refereegranskat)abstract
- The phenomenon of adult neurogenesis has been demonstrated in most mammals including humans. At least two regions of the adult brain maintain stem cells throughout life; the subgranular zone (SGZ) of the hippocampal dentate gyrus, and the subventricular zone (SVZ) of the lateral ventricle wall. Both regions continuously produce neurons that mature and become integrated into functional networks that are involved in learning and memory and odor discrimination, respectively. Apart from these well-studied regions neurogenesis has been reported in a number of other brain regions, such as amygdala and cortex. However, these studies have been contested and there is currently no well-postulated function for non-SVZ/SGZ neurogenesis. The studies of the regional localization of neurogenesis in the brain have been made possible due to several methods for detecting adult neurogenesis including; bromodeoxyuridine labeling (BrdU) together with markers of mature neurons, genetic labeling, by mouse transgenesis, or with the use of viral vectors. These techniques are already put to creative use and will be essential for the discovery of the nature of the adult neural stem cells. In this mini-review, we will discuss the localization of neural stem/progenitor cells in the brain and their implications as well as discussing the pro's and con's of stem cell labeling techniques.
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| 10. |
- Lindwall, Charlotta, et al.
(författare)
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Selective expression of hyaluronan and receptor for hyaluronan mediated motility (Rhamm) in the adult mouse subventricular zone and rostral migratory stream and in ischemic cortex
- 2013
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Ingår i: Brain Research. - : Elsevier BV. - 0006-8993. ; 1503, s. 62-77
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Tidskriftsartikel (refereegranskat)abstract
- Hyaluronan is a large glycosaminoglycan, which is abundant in the extracellular matrix of the developing rodent brain. In the adult brain however, levels of hyaluronan are significantly reduced. In this study, we used neurocan-GFP as a histochemical probe to analyze the distribution of hyaluronan in the adult mouse subventricular zone (SVZ), as well as in the rostral migratory stream (RMS). Interestingly, we observed that hyaluronan is generally downregulated in the adult brain, but notably remains at high levels in the SVZ and RMS; areas in which neural stem/progenitor cells (NSPCs) persist, proliferate and migrate throughout life. In addition, we found that the receptor for hyaluronan-mediated motility (Rhamm) was expressed in migrating neuroblasts in these areas, indicating that Rhamm could be involved in regulating hyaluronan-mediated cell migration. Hyaluronan levels are balanced by synthesis through hyaluronan synthases (Has) and degradation by hyaluronidases (Hyal). We found that Has1 and Has2, as well as Hyal1 and Hyal2 were expressed in GFAP positive cells in the adult rodent SVZ and RMS, indicating that astrocytes could be regulating hyaluronan-mediated functions in these areas. We also demonstrate that hyaluronan levels are substantially increased at six weeks following a photothrombotic stroke lesion to the adult mouse cortex. Furthermore, GFAP positive cells in the pen-infarct area express Rhamm. Thus, hyaluronan may be involved in regulating cell migration in the normal SVZ and RMS and could also be responsible for priming the peri-infarct area following an ischemic lesion for cell migration. (C) 2013 Elsevier B.V. All rights reserved.
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