18 February 2008

Hippocampal and Olfactory Neurons Regenerate

Towards the end of our last discussion the question came up about neuron regeneration. There are actually two two different types of neurons that are able to regenerate. We have been taught and had the understanding for the longest time that neurons do not regenerate...thus don't go running around and getting too many concussions. However there has been research completed that says otherwise: that hippocampal and olfactory neurons DO regenerate. So I went looking for an article supporting some of this data and found that there happen to be multiple articles dated back to as early as 1999 that supports this. Here is a summary statement made by an article in 2007 with some of the latest developments towards research that is currently taking place based off of this idea.

Note: I posted only the statement because I had problems accessing the entire article, the citation is listed so if anyone can figure out how to locate a full version of the article for free, post it!

"It is now well documented that active neurogenesis does exist throughout the life span in the brain of various species including human. Two discrete brain regions contain progenitor cells that are capable of differentiating into neurons or glia, the subventricular zone and the dentate gyrus of the hippocampal formation. Recent studies have shown that neurogenesis can be modulated by a variety of factors, including stress and neurohormones, growth factors, neurotransmitters, drugs of abuse, and also strokes and traumatic brain injuries. In particular, the hippocampal neurogenesis may play a role in neuroadaptation associated with pathologies, such as cognitive disorders and depression. The increased neurogenesis at sites of injury may represent an attempt by the central nervous system to regenerate after damage. We herein review the most significant data on hippocampal neurogenesis in brain under various pathological conditions, with a special attention to mood disorders including depression and addiction."

2007 Oct;32(10):1762-71. Epub 2007 Apr 4.

PMID: 17406979 [PubMed - indexed for MEDLINE]

(here is a link to the old 1999 article)
http://www.princeton.edu/pr/pwb/99/0405/brain.htm

2 comments:

Alisa85 said...

I had the same trouble you did trying to access the article - but I did find some more interesting information pertaining to neuron regeneration/plasticity within the hippocampus:

Alterations of neuroplasticity in depression: the hippocampus and beyond. Fuchs, E., et al., 2004. This paper suggests that norepinephrine and serotonin may be partially responsible for this phenomenon.

Here's the link to a paper published from the Karolinska Institute of Stockholm, Sweden that's really interesting too (I'm still reading the 56 page beast): http://diss.kib.ki.se/2007/978-91-7357-439-6/thesis.pdf

Thanks for sharing about neuronal regeneration in the hippocampus!

LianH495 said...

Thanks to Dr. Zoe Cohen's help, here is the link to the entire article that I had trouble locating:

http://www.springerlink.com/content/a335g76476265051/fulltext.html