mpm at seqanal.mi.uky.edu
Mon Apr 4 09:02:48 EST 1994
RSTETTA at DELPHI.COM (rstetta at news.delphi.com) wrote:
: Looking for info on what Nuerotrophic Factors consist of,
: and what effects them.
: There is a form of muscular dystrophy, spinal muscle atrophy,
: in which the motor nuerons are affected, weaken over time.
: It is similiar to ALS (amyotrophic lateral sclerosis) but
: progresses at a much slower rate.
: The info I have comes second hand from my sister in Tucson
: who attended a conference where a researcher from Canada
: mentioned these neurotrophic factors.
: He also mentioned that the motor neurons were affected by
: Free Radicals. Interim use of anti-oxidants is in order.
: Thank you for any input,
: Barbara Stetta
: email : rstetta at delphi.com
The term "neurotrophic factor" can be defined as any discrete, identified
molecule that is trophic (that is, supports health and life) for neurons.
However, the current convention is to restrict the use of this term to
peptides and small proteins which bind a cell-surface receptor on neurons
and activate mechanisms involved in keeping the cell healthy and happy.
The prototype is nerve growth factor (NGF), now recognized as a member of
a family of related peptides termed "neurotrophins" which all support the
health and/or growth of neurons. Different family members seem to be
important for different types of neurons, but (as far as I know) none of
these has been shown to be trophic for the motor neurons which are lost
in ALS. These cells may be more dependent on other factors produced by the
muscles they innervate.
And, yes, oxidative damage can play a major role in loss of these neurons,
as evidenced by the recent demonstration that one familial form of ALS results
from a mutation in the gene for superoxide dismutase, an enzyme which helps
get rid of a particularly harmful oxygen free radical.
Steven W. Barger, Ph.D.
Sanders-Brown Center on Aging
More information about the Neur-sci