Functional contacts of adult born olfactory neurons in the mouse

Which cell types are targeted by neurogenesis in the olfactory bulb? To answer this question (among others), Bardi et al. used a optogenetic mouse model selective for adult-born olfactory cells to test various cell types for post-synaptic responsiveness following light stimulation. So if the (randomly chosen) cells in the olfactory bulb slices respond to light, as [...]

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Synaptic activity dependent survival via neurotrophins and training in newborn hippocampal neurons

Granulocyte-colony stimulating factor (GCSF) is a recently discovered neurotrophic factor that counteracts apoptosis, boosts synaptic plasticity, and, perhaps through the same mechanism, increases neurogenesis. Diederich et al (here) have an interesting study showing that the beneficial cognitive effects of training on a radial maze for 11 days and receiving daily 20 µg/kg injections of G-CSF [...]

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Correlations Between Neurogenesis and Behavior

Jason Snyder has compiled a very interesting list of 224 studies that have attempted to correlate neurogenesis with behavior while controlling for outside variables. Check out the full list here. Taking the author’s assertions at face value, it appears that 14/47 (29.8%) studies that correlated neurogenesis with depression / anxiety found a significant association, 0/12 [...]

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Characterizing neural development based on single neuron analysis

Yu et al recently reported their use of twin-spot mosaic analysis with repressible cell markers to track the development of clusters of neurons in Drosophila. This is an exciting avenue of research because development is so tightly linked to cell phenotype, and classifying all brain cell types is a major goal of neuroscience. Aside from [...]

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Neurogenesis induces anxiety?

Voluntary wheel running in rodents is correlated with an upregulation of adult neurogenesis, as well as activation of the HPA axis. However, the findings on the effects of voluntary exercise on anxiety have been ambiguous, with some tests indicating no change, some indicating a decrease, and some indicating an increase, the latter of which may [...]

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Two pathways towards enhanced adult neurogenesis

Tashiro et al (2007) describe how mice exposed to an “enriched environment”, meaning larger cages with tunnels and running wheels, can have higher levels of neurogenesis than those without that exposure. That finding in itself is not new, but their team found that mice exposed to the enriched environment for just one week showed an [...]

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Stem cells reverse birth defects in the brains of mice

MIT’s Technology Review reports: By injecting stem cells directly into the brain, scientists have successfully reversed neural birth defects in mice whose mothers were given heroin during pregnancy. Even though most of the transplanted cells did not survive, they induced the brain’s own cells to carry out extensive repairs. … [T]hey are consistent with an [...]

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Effect of melatonin on neurogenesis in the recovery from irradiation

Radiation treatment is a crucial tool for treating brain tumors, but it has the unfortunate side effect of promoting cognitive decline. One of the pathways that this is believed to occur is through decreased neurogenesis in the dentate gyrus of the hippocampus. Manda et al recently investigated the support for this hypothesis using a mouse [...]

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Peptide amphiphile matrix hinders scar development after spinal cord injury

The spinal cord is a crucial component of the CNS and efforts to recovery from injuries to it mirror the kind of efforts that will be undertaken to combat injury to the brain. Tyselling-Mattiace et al. recently analyzed the effects of peptide amphiphiline (PA) molecules that self-assemble into cylindrincal nanofibers incorporated into isoleucine-lysine-valine-alanine-valine (IKVAV), a [...]

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The effect of seizures on hippocampal neurogenesis

Some of the factors that are known to affect the extent of neurogenesis in the subgranular zone of the hippocampus are exercise (enhances), exposure to enriched environment (ie, more ways for rats to be active in their cages; enhances), and seizures. Seizures are perhaps the most interesting of the three, because the way that they [...]

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