[ RadSafe ] RE: hormesis mechanism of action

[Muckerheide, James]

Then you haven't read much of the hormesis biology literature.  But of course
"hormesis" is the normal biological response to critical stressors required
for good biological functions (inlcuding e.g., heat and exercise, and normal
oxidative metabolism).  If you have good health (including exercise) and
nutrition, additional stimulation may not be of great consequence - like
taking vitamin and mineral supplements, essential if you aren't getting them,
of limited use if you are getting them through normal diet.

LDR (as with other hormetins) does stimulate SOD, Gpx, etc., but a great deal
more. In one case, medical research was claiin success in stimulating p53 in
the brain by about 30%, while LDR stimulates p53 in the brain by something
like a factor of 3 to 5.  These results have dramatic effects in many cases.

For some immunological studies at Norman Bethune University (now part of
Jilin Univ.), see, e.g., a presentation by Dr. Liu at:
http://cnts.wpi.edu/RSH/Docs/LiuAmherst2002ppt_files/v3_document.htm 
and http://cnts.wpi.edu/RSH/Docs/LiuANS_Nov2002.htm 

See also:  http://cnts.wpi.edu/rsh/docs/Liu_Munich_2000.htm 

and abstracts from 85 refs from work at Dr. Liu's lab between 1995 and 2000
at:
http://cnts.wpi.edu/rsh/docs/shuzheng_liu_et_al_abstracts.htm 

For some more examples of the general in vivo biology literature see Section
3.0, esp under 3.2.2 and 3.2.3 at:
http://cnts.wpi.edu:9000/rsh/dd3/_database.jsp 

Section 3.3 includes more on mechanisms (not health effects) from the in
vitro research.  There are very many more general treatments of the subject,
from evolutionary biology to biophysics.  

We can also be certain that DNA damage from LDR has nothing to do with health
effects (or even HDR that DOES cause latent cancer and other health effects)
simply because it is thousands of times less than normal DNA damage rates
from osidative metabolism for DSBs and millions of times less than for SSBs,
even without the proven enhancement of biological functions, and healing,
from LDR.  See, e.g., the 4th item down under "Science Papers" by Ludwig
Feinendegen and myron Pollycove at:
http://cnts.wpi.edu/rsh/docs/index_science.html 

You can find many more examples of the science literature and general article
sources at:
http://cnts.wpi.edu/rsh/docs/ 

As a footnote, I would have to disagree with Jerry Cohen in stating that
cadmium, lead and mercury do not indicate hormetic effects. 

Jerry,  We have distributed a number such papers over the last few years on
the RSH mailing list.  Ed Calabrese's work on hormesis data and toxicology
has documented such results.  Unfortunately, not all of these sources are in
the database (yet). :-)  But you can review the database and just do a search
on pubMed for "homesis" and "metal"  or with the individual metals.  This is
a limited effect since, as Ed has documented extensively, the term hormesis
and non-linear dose-response results are often not reported eeven when they
exist.  You can review Ed's papers for relevant documentation!

Regards, Jim Muckerheide


-----Original Message-----
From: James Salsman [mailto:james at bovik.org]
Sent: Sun 5/8/2005 3:55 PM
To: jjcohen; hflong at pacbell.net
Cc: Muckerheide, James; radsafe at radlab.nl
Subject: hormesis mechanism of action
 
All of the papers I have read on hormesis do not suggest any
mechanism of action more specific than e.g. "stimulates the
immune system" or "causes slight damage activating repair
mechanisms which provide a beneficial effect."

It seems very odd that hormesis proponents apparently do not
consider that such repair mechanisms might be activated by a
signaling substance within the cell which is not associated
with toxic chemicals or ionizing radiation.

If the "repair mechanisms are just ordinary superoxide dismutase, 
catalase, and glutathione peroxidases -- which seems likely
because the harmful effects of both ionizing radiation and toxic
heavy metals involves the production of hydroxyl and other free
radical ions as the primary source of tissue damage -- then those
interested in hormesis might benefit from study of the ependymin
peptides and other stimulants of SOD, CAT, and Gpx.

Jerry Cohen wrote:

 > Hormesis can be considered a general rule in nature, but not
 > a universal rule  since there are exceptions. For example,
 > 3 heavy metals that show no evidence of hormesis are lead,
 > cadmium, and mercury.

So, for which heavy metals is there evidence for hormesis, and
where is it documented?

Howard Long stated that cobalt in vitamin B-12 is essential,
which is true in that B-12 is essential.  But no other form of
cobalt, including elemental, is neither helpful or toxic:

"Cobalt and its salts are relatively non toxic by ingestion.
Most cases of cobalt toxicity relate to occupational skin
contact or inhalation."
   -- http://www.intox.org/databank/documents/chemical/cobalt/ukpid52.htm

The article Howard Long recently suggested is here:
   http://www.sepp.org/NewSEPP/radiation_trace_energy.htm
It only mentions cobalt in the context of gamma rays from Co-60.

Sincerely,
James Salsman