Adult neurogenesis

Not to be confused with Neuroregeneration.
BrdU (red), a marker of DNA replication, highlights neurogenesis in the subgranular zone of hippocampal dentate gyrus. Fragment of an illustration from Faiz et al., 2005.[1]
Doublecortin expression in the rat dentate gyrus, 21st postnatal day. Oomen et al., 2009.[2]

Adult neurogenesis is the process in which neurons are generated from neural stem cells in the adult. This process differs from prenatal neurogenesis.

In most mammals, new neurons are born throughout adulthood in two regions of the brain:[3]

More attention has been given to the neurogenesis in the dentate gyrus than in the striatum. In rodents, many of the newborn dentate gyrus neurons die shortly after they are born,[4] but a number of them become functionally integrated into the surrounding brain tissue.[10][11][12] Adult neurogenesis in rodents is reported to play a role in learning and memory, emotion, stress, depression, response to injury, and other conditions.[13]

The numbers of neurons born in the human adult hippocampus remains controversial; some studies have reported that in adult humans about 700 new neurons are added in the hippocampus every day,[14] while more recent studies show that adult hippocampal neurogenesis does not exist in humans, or, if it does, it is at undetectable levels.[15] Recent evidence shows that adult neurogenesis is basically extinct in humans.[16] The experiments advocating for the presence of adult neurogenesis have focused on how dual antigen retrieval finds that DCX antibodies are staining many cells within the adult human dentate gyrus. This finding is not as clear though as supporters of adult neurogenesis suggest; the dentate gyrus cells stained with DCX have been shown to have a mature morphology, contrasting the idea that novel neurons are being generated within the adult brain.[17] The role of new neurons in human adult brain function thus remains unclear.

  1. ^ Faiz M, Acarin L, Castellano B, Gonzalez B (2005). "Proliferation dynamics of germinative zone cells in the intact and excitotoxically lesioned postnatal rat brain". BMC Neuroscience. 6: 26. doi:10.1186/1471-2202-6-26. PMC 1087489. PMID 15826306.
  2. ^ Oomen CA, Girardi CE, Cahyadi R, et al. (2009). Baune B (ed.). "Opposite effects of early maternal deprivation on neurogenesis in male versus female rats". PLOS ONE. 4 (1): e3675. Bibcode:2009PLoSO...4.3675O. doi:10.1371/journal.pone.0003675. PMC 2629844. PMID 19180242.
  3. ^ Ernst A, Frisén J (January 2015). "Adult neurogenesis in humans- common and unique traits in mammals". PLOS Biology. 13 (1): e1002045. doi:10.1371/journal.pbio.1002045. PMC 4306487. PMID 25621867.
  4. ^ a b Dayer A, Ford A, Cleaver K, Yassaee M, Cameron H (2003). "Short-term and long-term survival of new neurons in the rat dentate gyrus". The Journal of Comparative Neurology. 460 (4): 563–572. doi:10.1002/cne.10675. PMID 12717714. S2CID 7153599.
  5. ^ Vadodaria KC, Gage FH (2014). "SnapShot: Adult Hippocampal Neurogenesis". Cell. 156 (5): 1114–1114.e1. doi:10.1016/j.cell.2014.02.029. PMID 24581504.
  6. ^ Duan X, Kang E, Liu CY, Ming Gl, Song H (February 2008). "Development of neural stem cell in the adult brain". Current Opinion in Neurobiology. 18 (1): 108–115. doi:10.1016/j.conb.2008.04.001. ISSN 0959-4388. PMC 2464621. PMID 18514504.
  7. ^ Fiorelli R, Azim K, Fischer B, Raineteau O (2015-06-15). "Adding a spatial dimension to postnatal ventricular-subventricular zone neurogenesis". Development. 142 (12): 2109–20. doi:10.1242/dev.119966. ISSN 1477-9129. PMID 26081572.
  8. ^ Ernst A, Alkass K, Bernard S, Salehpour M, Perl S, Tisdale J, Possnert G, Druid H, Frisén J (2014). "Neurogenesis in the striatum of the adult human brain". Cell. 156 (5): 1072–83. doi:10.1016/j.cell.2014.01.044. PMID 24561062.
  9. ^ Bergmann O, Liebel J, Bernard S, Alkass K, Yeung M, Steier P, Kutschera W, Johnson L, Landen M, Druid H, Spalding K, Frisen J (2012). "The age of olfactory bulb neurons in humans". Neuron. 74 (4): 634–9. doi:10.1016/j.neuron.2012.03.030. PMID 22632721.
  10. ^ Toni N, Teng E, Bushong E, Aimone J, Zhao C, Consiglio A, van Praag H, Martone M, Ellisman M, Gage F (2007). "Synapse formation on neurons born in the adult hippocampus". Nature Neuroscience. 10 (6): 727–734. doi:10.1038/nn1908. PMID 17486101. S2CID 6796849.
  11. ^ Vivar C, Potter M, Choi J, Lee J, Stringer T, Callawy E, Gage F, Suh H, van Praag H (2012). "Monosynaptic inputs to new neurons in the dentate gyrus". Nature Communications. 3 (1038): 1107. Bibcode:2012NatCo...3.1107V. doi:10.1038/ncomms2101. PMC 4603575. PMID 23033083.
  12. ^ Toni N, Laplagne D, Zhao C, Lombardi G, Ribak C, Gage F, Schinder A (2008). "Neurons born in the adult dentate gyrus form functional synapses with target cells". Nature Neuroscience. 11 (8): 901–7. doi:10.1038/nn.2156. PMC 2572641. PMID 18622400.
  13. ^ Cameron HA, Glover LR (2015-01-03). "Adult Neurogenesis: Beyond Learning and Memory". Annual Review of Psychology. 66 (1): 53–81. doi:10.1146/annurev-psych-010814-015006. ISSN 0066-4308. PMC 5612417. PMID 25251485.
  14. ^ Spalding KL, Bergmann O, Alkass K, Bernard S, Salehpour M, Huttner HB, Boström E, Westerlund I, Vial C (2013-06-06). "Dynamics of hippocampal neurogenesis in adult humans". Cell. 153 (6): 1219–27. doi:10.1016/j.cell.2013.05.002. ISSN 1097-4172. PMC 4394608. PMID 23746839.
  15. ^ Sorrells SF, Paredes MF, Cebrian-Silla A, Sandoval K, Qi D, Kelley KW, James D, Mayer S, Chang J, Auguste KI, Chang EF, Gutierrez AJ, Kriegstein AR, Mathern GW, Oldham MC, Huang EJ, Garcia-Verdugo JM, Yang Z, Alvarez-Buylla A (15 March 2018). "Human hippocampal neurogenesis drops sharply in children to undetectable levels in adults". Nature. 555 (7696): 377–381. Bibcode:2018Natur.555..377S. doi:10.1038/nature25975. PMC 6179355. PMID 29513649.
  16. ^ Duque A, Arellano JI, Rakic P (January 2022). "An assessment of the existence of adult neurogenesis in humans and value of its rodent models for neuropsychiatric diseases". Molecular Psychiatry. 27 (1): 377–382. doi:10.1038/s41380-021-01314-8. ISSN 1476-5578. PMC 8967762. PMID 34667259.
  17. ^ Sorrells SF, Paredes MF, Zhang Z, Kang G, Pastor-Alonso O, Biagiotti S, Page CE, Sandoval K, Knox A, Connolly A, Huang EJ, Garcia-Verdugo JM, Oldham MC, Yang Z, Alvarez-Buylla A (March 2021). "Positive Controls in Adults and Children Support That Very Few, If Any, New Neurons Are Born in the Adult Human Hippocampus". J Neurosci. 41 (12): 2554–65. doi:10.1523/JNEUROSCI.0676-20.2020. PMC 8018729. PMID 33762407.