Our latest research on adult neurogenesis in the nucleus accumbens is finally out @MolPsychiatry!!!
A long-term project from the Monyer and Alfonso Labs in collaboration with the labs of R Kuner and JM García-Verdugo @DKFZ @UniHeidelberg @UV_EG
pdf here: https://rdcu.be/b5l8y 

2. In adult mice, neurogenesis persists in the V-SVZ and produces neuroblasts that migrate to the olfactory bulb, where they mature and become inhibitory interneurons processing olfactory information

3. We found neuroblasts around the anterior-ventral V-SVZ in adult mice –already the NAc (ventral striatum), which is associated with addiction, reward, aversion, etc. Of note, the number of neuroblasts declines with age.

4. We verified with several markers that those cells were indeed neuroblasts, not other cell types like OPCs or microglia expressing DCX. We also did electron microscopy together with Vicente Herranz @vherranz and JM García-Verdugo. Beautiful images! @UV_EG

5. But are those neuroblasts migrating or are they just hanging in there?
We recorded movies in brain slices and found neuroblasts actively migrating in the NAc

6. We also found looooooooong radial-glia like fibers (up to 1mm) targeting blood vessels (preferentially in the NAc) in the adult anterior-ventral V-SVZ!! And the amount of fibers also decreases with age!

7. And it turns out that neuroblasts in the NAc follow not only radial glia-like fibers, but also blood vessels!

8. But are those neuroblasts generated after birth?
Yes, and we showed it with 3 methods: BrdU administration in adult mice, retroviral injections in pups, and labeling of stem cells and their progeny in conditional transgenic (Nestin-CreERT2) adult mice

9. Newborn neuroblasts in the NAc become mature neurons, more specifically medium spiny neurons (MSNs) based on DARPP32 expression, the presence of spines and their electrophysiological properties. Interestingly, newborn MSNs do not project outside the NAc...

10. Although the function of the NAc has been classically linked to motivation and addiction, recent studies revealed that the NAc is also involved in chronic pain processing. Therefore, we asked ourselves if pain conditions might influence NAc neurogenesis

11. And the answer is yes, we also observed augmented neurogenesis after pathological pain -only in the NAc, not in the OB. We did these experiments with the help of Linette Tan and Rohini Kuner. These results are truly intriguing and open many new questions!

12. OK, the number of new neurons is modest: ~30/day (~3 orders of magnitude lower than OB neurogenesis). But the functional impact of newborn neurons cannot be inferred based on their number given that the activation of single neurons can translate into a defined behavior

13. In sum, new MSNs are continuously added to the NAc in adult mice. Intriguingly, pathological pain conditions that are not associated with neuronal death increase NAc neurogenesis

And 14. Here’s the paper to find out more https://www.nature.com/articles/s41380-020-0823-4
#AdultNeurogenesis #NucleusAccumbens
BTW, Ionut Dumitru is also first author! (not on twitter)
This work was supported by @dfg_public @sfb1158 @BMBF_Bund
Thanks for your interest!