home   genetic news   bioinformatics   biotechnology   literature   journals   ethics   positions   events   sitemap
 
  HUM-MOLGEN -> Genetic News | search  
 

Evidence Of A Spinal Motor Neuron Neurotrophic Factor

 
  March, 21 2007 6:32
your information resource in human molecular genetics
 
     
Mi, R., Chen, W., and Hoke, A. Pleiotrophin is a neurotrophic factor for spinal motor neurons. Proc. Nat. Acad. Sci., 104 (11), 4664-4669 (March 13, 2007).


A cDNA microarray was used to identify potential neurotrophic factors in denervated distal nerve stumps. Pleiotrophin (PTN) mRNA levels increase significantly in Schwann cells within two days after sciatic nerve transaction and remain elevated for at least a month. However, by the third month, PTN mRNA returns to baseline.

An analysis of PTN expression during development suggests that this 168 amino acid protein plays a role in normal embryogenesis. At embryonic day 14, PTN mRNA is roughly 11,000 times higher than in the adult rat tibialis anterior muscle. Following birth, the mRNA declines, reaching an adult level by postnatal day 30.

Addition of PTN or PTN expressing HEK-293 cells to cultures of spinal cord motor neurons enhances axonal growth and protects the neurons from excitotoxic effects of the glutamate transport inhibitor threohydroxyaspartate. Similar results were observed in vivo, following sciatic nerve transaction when PTN-expressing HEK-293 cells were included in a silicone tube used for supporting axon regeneration. The presence of PTN increases the number of regenerated myelinated axons, compared with control animals, and it leads to the reemergence of compound motor action potentials in sciatic nerve innervated foot muscles. PTNís neuroprotective properties were investigated in vivo by transecting the facial nerve in neonatal mice. Implants of HEK-293 cells that express the neurotrophic factor rescue the facial motor neurons.

A semiquantitative real-time RT-PCR analysis was used to identify which receptors were increased in response to axotomy. The results revealed that of the four possible PTN receptors, only anaplastic lymphoma kinase (ALK) is upregulated. Moreover, an antibody to ALK was able to block both the axonal regeneration and neuroprotective properties of PTN in cell cultures, indicating that ALK serves a crucial role in the PTN pathway.

The results open a new approach to a therapy that stimulates motor neuron regeneration clinically.


Message posted by: Keith Markey

print this article mail this article
Bookmark and Share this page (what is this?)

Social bookmarking allows users to save and categorise a personal collection of bookmarks and share them with others. This is different to using your own browser bookmarks which are available using the menus within your web browser.

Use the links below to share this article on the social bookmarking site of your choice.

Read more about social bookmarking at Wikipedia - Social Bookmarking

Latest News
Variants Associated with Pediatric Allergic Disorder

Mutations in PHF6 Found in T-Cell Leukemia

Genetic Risk Variant for Urinary Bladder Cancer

Antibody Has Therapeutic Effect on Mice with ALS

Regulating P53 Activity in Cancer Cells

Anti-RNA Therapy Counters Breast Cancer Spread

Mitochondrial DNA Diversity

The Power of RNA Sequencing

ĎPro-Ageing' Therapy for Cancer?

Niche Genetics Influence Leukaemia

Molecular Biology: Clinical Promise for RNA Interference

Chemoprevention Cocktail for Colon Cancer

more news ...

Generated by News Editor 2.0 by Kai Garlipp
WWW: Kai Garlipp, Frank S. Zollmann.
7.0 © 1995-2017 HUM-MOLGEN. All rights reserved. Liability, Copyright and Imprint.