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Ray D’Alonzo, Ph.D., is an Associate Director of Research and Development
at Procter & Gamble Pharmaceuticals where he has worked for 29 years and led
research programs in bone metabolism, infectious disease, respiratory
disease, arthritis, and nutrition. He has published scientific papers on a
wide variety of topics from the chemical composition of fats and oils to the
pharmacoeconomics of osteoporosis. Dr. D’Alonzo is the recipient of the
Chancellor’s Medal from the University of Massachusetts, Amherst, in part,
for his contributions to the development of new pharmaceutical agents. As
both a patient and scientist, he has made a personal effort to increase the
awareness of Chiari in the health care sector and to assist others afflicted
with the syndrome. He has published the story of his personal struggle
with Chiari in a book,
Contents Under Pressure,
with 100% of royalties going towards Chiari education, awareness, and
research programs.
November 20, 2006 -- I thought I would write about nanotechnology and
brain tissue repair this month with a focus on a recently published paper
from the Massachusetts Institute of Technology (MIT)1. The paper reports on
the repair of severed optic nerves in animals, hamsters to be specific and
was first reported in Conquer Chiari in the April 2006 edition. The question
is can this technology hold promise for repairing brain tissue damaged from
the compressive forces associated with Chiari?
Before answering this question, let me provide some background. First, what
is nanotechnology? Nano is a prefix that means one-billionth. For example,
one billion nanoseconds equal one second. Applied to length, a nanometer is
one-billionth of a meter. A human hair is about 10,000 nanometers wide.
Nanotechnology is technology on an extremely small scale. In electronics,
nanotechnology might mean circuits that are so small they can only be seen
with a powerful electron microscope. Such circuits may be so small that they
approach the size of individual molecules. In engineering, nanotechnology
conjures up images of super small machines, machines the size of a single
cell or smaller with highly advanced functions.
In chemistry and biochemistry, nanotechnology often refers to molecules that
are highly ordered in their structure and possess unique properties or
functions as a result. It can also refer to molecules with the potential for
self-assembly.
Recently, researchers at MIT utilized a unique molecule that can
self-assemble into a fibrous network within damaged sections or areas of
nervous tissue to “allow” repair and healing. The molecule is made from
common amino acids which are the building blocks of proteins. The molecule
is known as SAPNS. The SAPNS building block is very small. Its length is 5
nanometers and its width, 1.3 nanometers. It would take 2,000 of these
building blocks attached end to end to stretch across the width of a human
hair.
These SAPNS building blocks can hook together on their own to form a fibrous
network with unique properties. The fibrous network formed by SAPNS self
assembly acts as a scaffold to tie damaged nervous tissue together in such a
way as to permit axonal regeneration without provoking an immune
response or the formation of scar tissue.
The researchers at MIT severed the optic nerve of several hamsters. In one
group of hamsters, SAPNS was injected into the severed nerve and the other
group, saline was injected as a control. The results were nothing short of
remarkable. Hamsters treated with SAPNS showed healing that was so complete
it almost appeared as normal whereas no healing of tissue was observed in
the control animals. Behavioral testing (orienting towards a small object)
was also conducted in the hamsters to determine if actual vision was
restored. 75% of the SAPNS treated animals showed a return in visual ability
while hamsters in the control group demonstrated behavior consistent with
blind animals.
Finally, the investigators looked at the metabolic fate of SAPNS and found
that it was broken down to L-amino acids which were either used by
surrounding tissue in the healing process or excreted in the urine.
Without a doubt SAPNS has great potential as a safe and effective treatment
for axonal repair. However, there are different types of nerve tissue damage
and several barriers to regeneration. Nerve tissue can be cleanly severed
but it can also be crushed. Also, prolonged damage may be covered over with
scar tissue. The barriers to regeneration include 1) scar tissue as just
mentioned, 2) gaps in nerve tissue formed during resorption of dying cells
after injury, 3) factors that inhibit axon growth in mature animals, and 4)
failure of many adult neurons to initiate axonal extension.
The MIT experiment with SAPNS appears to overcome the first two barriers.
SAPNS' effectiveness against the last two barriers is less clear. The damage
caused by the compressive forces associated with Chiari is unlike that in
the MIT experiment. Nerve tissue is not cleanly severed in Chiari. The
damage can not be readily detected. While some very sophisticated imaging
techniques can locate areas of the brain responsible for processing certain
tasks, it can’t locate precisely where damage may reside in specific
individuals. Even if the damaged tissue could be precisely located getting SAPNS to the damaged tissue without disrupting healthy tissue represents a
formidable task which brings me back to the picture above. Nanobiochemical
technology may require an assist from nanoengineering technology. Some sort
of nano-size device that can navigate through the body at the cellular level
to locate damage and deliver a treatment agent such as SAPNS just might be
able to do the trick. I guess we can all dream but dreams often come true.
When my father was a boy in the 1920’s, the notion of going to the moon was
a distant dream. Just ten years ago, an agent to regenerate a severed optic
nerve in hamsters was a distant dream.
The dreams and more importantly, the hard work of these MIT researchers is
to be highly commended. These are the true heroes of healing deserving of
our respect. After all, I am not aware of a single Reiki master who has
restored vision in a hamster with surgically severed optic nerves.
1Rutledge G, Ellis, Yu-Xiang Liang, Si-Wei You, David K. C. Tay, Shuguang
Zhang, Kwok-Fai So, and Gerald E. Schneider: PNAS 2006;103:5054-5059.
--Ray D'Alonzo, PhD
** If you
would like to share your comments, thoughts, or ideas with Ray,
please send them to dalonzo.rp@fuse.net.
Due to the volume and nature of email received, individual responses are not
possible. **
[Ed. Note: The opinions expressed above are solely those of the
author. They do not represent the opinions of the editor, publisher,
or this publication. Mr. D'Alonzo is not a medical doctor and does not
give medical advice. Anyone with a medical problem is strongly
encouraged to seek professional medical care.]
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