rexresearch.com
Will TAYLOR, et al.
Selenium vs Ebola
http://www.youtube.com/watch?v=4g-ZYth7ZUk#t=887
http://orthomolecular.org/library/jom/1995/articles/1995-v10n0304-p131.shtml
Theoretical
Evidence that the Ebola Virus Zaire Strain May Be
Selenium-Dependent: A Factorin Pathogenesis and Viral
Outbreaks?
Ethan
Will Taylor1 and Chandra Sekar Ramanathan
Abstract
A theoretical analysis of the genomic structure of the Ebola
virus Zaire strain reveals the existence of several open reading
frames (ORFs) containing large numbers of inframe UGA codons.
This clustering of UGA codons is very unlikely to have arisen by
chance, and raises the possibility that these ORFs may encode
selenoproteins, since, in addition to its usual role as a stop
codon, UGA can under certain conditions encode selenocysteine.
The other major requirement for selenocysteine insertion at UGA
codons appears to be met in this case, due to the presence of
selenocysteine insertion sequences (SECIS) in stable stem-loop
structures in the appropriate Ebola Zaire mRNAs. Specifically,
there is a SECIS in the 3’untranslated region of the
nucleoprotein mRNA, where the largest potential selenoproteins
are encoded, one of which may contain up to 16 selenium atoms
per molecule. The expression of this hypothetical protein could
impose an unprecedented selenium demand upon the host,
potentially leading to severe lipid peroxidation and cell
membrane destruction. This could also contribute to the
characteristic hemorrhaging caused by intravascular blood
clotting, due to the thrombotic effect of Se deficiency. The
possibility that this gene might contribute to the extreme
pathogenicity of the Zaire strain of Ebola virus by this
mechanism is also consistent with the observation that this
potential selenoprotein gene is not present in the Ebola Reston
strain, which was not pathogenic in humans.
http://drsircus.com/medicine/ebola-saving-lives-natural-allopathic-medicine
Resolving
Cytokine Storms with Selenium
The highly pathogenic Zaire strain of the Ebola virus may be
dependent on the trace mineral selenium (Se), due to the
presence in the Ebola genome of several open reading frames
(ORFs) containing clusters of up to 17 inframe UGA codons, which
potentially encode the rare amino acid selenocysteine (SeC).
This raises the possibility that Se deficiency in host
populations may actually foster viral replication, possibly
triggering outbreaks linked and perhaps even facilitating the
emergence of more virulent viral strains. [2]
Selenium is a strong antioxidant and anti-inflammatory that can
control the cytokine storms provoked from out of control
infections. The clinical investigations in sepsis studies
indicate that higher doses of selenium are well tolerated as
continuous infusions of selenium as sodium selenite (4,000 µg
selenium as sodium selenite pentahydrate on the first day, 1,000
µg selenium/day on the nine following days) and had no reported
toxicity issues. In view of this new information, Biosyn
introduced the 1,000 µg dose vials for such high selenium
clinical usage.
The primary symptoms of a cytokine storms are high fever,
swelling and redness, extreme fatigue and nausea. In Ebola a
combination of factors lead to death so we chose a combination
approach that deals with all the factors. In Ebola the
immune reaction may be fatal with cytokine storms. To stop the
cytokine storms and acute respiratory distress inject selenium
or force the world of medicine to produce Dr. Emanuel Revici’s
liposomal selenium, which can be administered orally in
extraordinarily high dosages, much higher than is available
through injections.
Dr. Revici’s greatest discovery was that if we want to deliver a
nutrient to a sick cell – attach it to a fat. Unsaturated
fats are the ultimate and perfect vehicle to deliver nutrients
to stressed cells. This discovery enabled Dr. Revici to
package therapeutic minerals, at will, to delivery only to sick
cells. This gave him a huge advantage as a therapy developer –
especially with selenium.
Revici used a special molecular form of selenium
(bivalent-negative selenium) incorporated in a molecule of fatty
acid. In this form, he can administer up to 1 gram of selenium
per day, which corresponds to 1 million micrograms per day,
reportedly with no toxic side effects. In contrast, too much
selenite (hexavalent-positive selenium) has toxic effects on
animals, so human intake of commercial selenite is limited to a
dosage of only 100 to 150 micrograms by mouth. Dr. Revici often
administered his nontoxic form of selenium by injection, usually
considered to be four times more powerful than the form given
orally.
The last 25 years the average daily selenium intake has fallen
from 60µg/day to 35µg/day. The UK government has
established a Reference Nutrient Intake (RNI) level of selenium
at 75µg/day. Therefore a nutritional gap now exists
between the actual recommended level of daily selenium and what
people are actually achieving through their diets.[3]
I believe I am the only doctor who has written a book on
Selenium. I have safely used dosages on myself of a special form
of selenium 100 times what would normally be thought of as
rational to great effect. Selenium influences both the innate,
"non-adaptive" and the acquired, "adaptive" immune
systems[4]-[5]-[6]-[7]-[8] The innate immune system includes
barriers to infection and nonspecific effector cells such as
macrophages. Both the T and B lymphocytes form the major
effector cells of the acquired system that mature with exposure
to immune challenges.
Selenium-deficient lymphocytes are less able to proliferate in
response to mitogen, and in macrophages, leukotriene B4
synthesis, which is essential for neutrophil chemotaxis, is
impaired by this deficiency. These processes can be improved by
selenium supplementation. The humoral system is also affected by
selenium deficiency; for example, IgM, IgG and IgA titers are
decreased in rats, and IgG and IgM titers are decreased in
humans. In endothelial cells from asthmatics, there is a marked
selenium deficiency that results in an increase in expression of
adhesion molecules, which causes greater adhesion of
neutrophils.[9]
Selenium is also involved in several key metabolic activities
through its selenoprotein enzymes that protect against oxidative
damage.[10] Further, selenium deficiency may allow invading
viruses to mutate and cause longer-lasting, more severe
illness.[11] Animal research has shown selenium and vitamin E
have synergistic effects, enhancing the body’s response to
bacterial[12] and parasitic infections.[13]
In that selenium is a potent immune stimulator is an 18-month
study of 262 patients with AIDS that found those who took a
daily capsule containing 200 micrograms of selenium ended up
with lower levels of the AIDS virus and more health-giving CD4
immune system cells in their bloodstreams than those taking a
dummy pill.
These AIDS patients who took selenium were able to suppress the
deadly virus in their bodies and boost their fragile immune
systems, adding to evidence that selenium has healing powers we
need to pay attention to in treating Ebola patients.[14] Those
with severely compromised immune systems due to AIDS had
dramatically better immune system response with selenium
supplementation and this finding is consistent with the
information presented by the NIH on their selenium web site.
http://www.whale.to/m/selenium.html
Selenium
Against Viruses: More Exciting Research from Dr. Will
Taylor
By
Richard A. Passwater, Ph.D.
You are witnessing a scientific breakthrough develop from theory
to public health practice. In November 1994, Dr. Will Taylor,
Associate Professor in the Department of Medicinal Chemistry at
the University of Georgia, explained his hypothesis that opened
new inroads into possibly controlling many viruses including
AIDS, Ebola and even several "more-routine" viruses. Last month,
Dr. Marianna Baum of the University of Miami discussed her
published results with selenium and HIV/AIDS. We didn't discuss
her latest results because they had not yet been peer-reviewed
for publication, but I can tell you that they are very exciting.
Dr. Orville Levander of the USDA has published his latest
findings with selenium and viruses. These three aspects of
research with selenium and human viruses recently gained
interest at an International Conference on the subject held in
Germany in April.
As one who has conducted laboratory research with selenium and
other antioxidants for more than 35 years, I can attest to the
scientific and public health importance of this "new direction"
in virus research. I don't believe that I have used that
terminology to describe completely new concepts since my 1973
publication, "Cancer: New Directions," in which I reported my
laboratory research showing that selenium and other antioxidants
reduce the incidence of cancers. [American Laboratory 5(6) 10-22
(1973)] By the way, an upcoming chat with Dr. Larry Clark will
discuss his clinical trial which found that selenium supplements
can cut the cancer death rate in half.
Let's chat again with Dr. Taylor to see how his new theory has
had an effect on AIDS and viral research. It is not necessary to
understand the technical aspects of the theory, just that, as
his analogy illustrates, that selenium can be a birth control
pill to some deadly viruses. If you are interested in the
details of his theory, please refer to our November 1994
discussion which describes it in detail.
Passwater: Dr. Taylor, it has only been two years since we
discussed your exciting new theory about selenium and HIV, but
thanks to your new concept, a lot of important and exciting
related findings have resulted in that relatively brief time as
research goes. Not only has selenium and AIDS research leaped
ahead, but research with selenium on many viruses from the rare
Ebola to the common flu has produced dramatic findings.
Are you pleased with the way in which some researchers are
comprehending the significance of your research on the role of
selenium in limiting the spread of at least some viruses? Or are
you disappointed that more scientists have failed to look into
this relationship?
Taylor: There certainly are a lot of exciting developments about
selenium and viruses, some of which is new work and some of
which is research that is only now gaining the attention it
deserves, even though it was done a few years back. I am
referring to the use of selenium to treat an Ebola-like
hemorrhagic fever that broke out in China in the late 1980s.
Hemorrhagic fevers can kill up to 90 percent of those infected,
but this study showed that selenium supplementation can reduce
that mortality rate dramatically. But let's talk about that
later.
From my perspective, however, I'd honestly have to say that
despite the accumulation of supporting evidence, it has been
somewhat frustrating to me that few major virology groups have
made any attempt, let alone a serious effort, to rigorously
prove or disprove what I now call the "viral selenoprotein
theory." In essence that hypothesis, first proposed in my 1994
paper, is the idea that certain viruses (initially HIV, other
retroviruses, and also some strains of Coxsackievirus) may
interact directly with selenium in host cells by incorporating
selenium into viral proteins. This would mean that the role of
selenium deficiency in some viral diseases might be far more
complex than previously thought - and believe me, the potential
roles of selenium and other antioxidants in the body's defenses
against infectious disease are already very complicated, even
without this possibility.
On the positive side, a number of studies have recently come out
or are being prepared for publication (Allavena et al. 1995,
Constans et al. 1995, Look et al. in press, Baum et al. in
preparation), confirming that low serum or plasma selenium is a
highly significant correlate of HIV disease progression, and a
risk factor for mortality. While this does not prove anything
about the MECHANISMS involved, there seems to be more going on
here than a simple nutritional effect, and these observations
are consistent with my 1994 prediction, based on theoretical
genomic evidence, that dietary selenium might inhibit HIV
replication and slow disease progression. Of course, based on
his studies of the mouse mammary tumor virus (MMTV), a
retrovirus relative of HIV, Dr. Gerhard Schrauzer had already
predicted over ten years ago that selenium would have an
anti-HIV effect. So he has had to be far more patient than I
have so far, in waiting to see his idea rigorously tested.
The most encouraging development on the clinical side is the
long-overdue initiation of some rigorous clinical studies of
selenium supplementation in HIV patients. These include a study
by Dr. Marianna Baum in Miami, and a study in African AIDS
patients that is being set up by Prof. Luc Montagnier of the
Pasteur Institute, who recently told me that he thought the data
on selenium and HIV are now sufficiently compelling as to
justify such a study. I find that very gratifying, particularly
since most AIDS patients in impoverished nations in Africa and
elsewhere are unlikely to receive any of the expensive new
antiviral drugs, like the HIV protease inhibitors. In those
countries, all they can realistically hope for is inexpensive
ways of slowing down the disease until a vaccine is found- and
there is nothing I know of that can do this that is cheaper than
selenium!
Passwater: Dr. Montagnier is the discoverer of HIV. Our readers
may wish to review his research in the September 1995 issue.
When I visited Dr. Montagnier in his Pasteur Institute
Laboratory, I handed him our 1994 article and he became very
interested in your theory. Also, I used that article to
introduce your theory to Dr. Baum and she became very interested
in your theory as she commented in last month's column.
Are clinical researchers better understanding the significance
of the role of selenium acting directly on viruses themselves,
as opposed to protecting the host via such mechanisms as
stimulating the immune system?
Taylor: It has been my impression that there has been a lot of
interest in my research among practitioners of holistic or
alternative medicine, and M.D.s who appreciate the value of
prevention and nutritional approaches to therapy, but that
"mainstream" HIV clinicians are less likely to have heard of it,
or indeed to place much hope in any type of nutritional
supplementation approach. Thanks to a story in Dr. Jonathan
Wright's excellent newsletter, "Nutrition and Healing", I have
been invited to present these concepts to a large group of M.D.s
at a meeting of the "American College for Advancement in
Medicine" in Tampa, Fl, next spring.
There is no doubt that part of what is catching these people's
attention is the idea that selenium may have a direct effect on
some viruses, rather than merely a non-specific immune-boosting
effect. However, it's the whole story - putting my findings in
the context of the various Chinese selenium studies, the work of
Drs. Levander and Beck, Dr. Schrauzer, and so on - that is so
intriguing.
Passwater: There is no doubt that you will have an interested
audience at the ACAM Conference. These medical practitioners are
very familiar with selenium. In addition to the clinical studies
that you mentioned, linking selenium status to HIV disease
progression, what are some of the specific new developments that
you can point to as support for your "viral selenoprotein
theory"?
Taylor: There is not as much as I'd like, because in many ways
the theory has hardly been tested. However, we can say with
considerable confidence that there is now virtually no doubt
that some viruses can make selenoproteins - it's more a matter
of which viruses can do it. This statement is possible because
Dr. Bernard Moss, a scientist at the National Institutes of
Health (NIH), recently reported the complete DNA sequence of a
common wart virus, the pox virus Molluscum contagiosum. This
virus appears to encode a gene that is 80% identical to the
known mammalian selenoprotein glutathione peroxidase (GPx). So
far he's only done what I have for HIV: show the potential gene
is there by theoretical analysis. But with such an unmistakable
match to a known selenoprotein, there's no reason to doubt that
this is a real GPx gene.
Similarly, we have now demonstrated GPx-like sequences in
Coxsackie B virus, the viral cofactor for Keshan disease, and
the subject of the now famous Levander and Beck studies. If our
readers will bear with me for just a moment, I want to point out
to our technical readers that other developments include a
published experimental verification of an RNA "pseudoknot" that
we predicted in HIV, in vitro experimental verification in my
lab of a novel frameshift site in HIV associated with a
conserved UGA codon, and most recently, from the lab of a
collaborating virologist, immuno-histochemical evidence in
patient samples for some novel HIV protein variants that I
predicted. Finally, in the test tube, selenium has been shown to
be a potent inhibitor of HIV reactivation from latently infected
cells. In summary: still no absolute direct proof that a virus
can make a selenoprotein, but an increasingly strong body of
favorable circumstantial evidence.
Passwater: When we discussed the mechanisms you elucidated and
presented in your hypothesis, we also included a glossary for
the non-virologists. Just so our non-virologists don't have to
go back to that article or reach for their scientific
dictionary, a codon is a three-letter code in DNA or RNA that
directs insertion of an amino acid into proteins, a frameshift
is a shift into a new protein coding region, a pseudoknot is an
RNA structure that promotes frameshifts, and UGA not only stands
for the University of Georgia but either a "stop" signal for
protein synthesis or for selenocysteine insertion.
As I mentioned, I have had the pleasure of introducing your
research to several clinical investigators, yet, I am still
struggling to get the concept across to many nutritionists and
clinical researchers who are not overly familiar with stop
codons, frame shifts and pseudoknots. I have the advantage of
getting help from my youngest son, Michael, when it comes to
complex modern virology. You may recall that the fact that my
oldest son, Richard, graduated from the University of Georgia
that led me to your earlier research. Rich and I deal with
antioxidants more than viruses. Now I find it ironical that what
seems like just a few years ago that Mike asked, "Hey, Dad,
what's DNA?" Now, I have to ask, "Hey Mike, why do RNA-based
viruses mutate more than DNA-based viruses? Or "Why do the HIV
family of viruses have the highest mutation rates among a family
(retroviruses) of viruses with high mutation rates?"
Mike pointed out that the fleets of enzymes which check, double
check, and transcribe DNA are at least as important as the DNA
itself. RNA is not protected as well. Perhaps it would help
clarify your findings if I lead you through the same line of
questioning that Mike led me through when we first discussed
your research. Could you briefly explain the significance of UGA
codons in your findings on HIV, and how that may relate to the
role of the known Selenium-containing antioxidant enzyme you
mentioned earlier, glutathione peroxidase (GPx)?
Taylor: In essence, the UGA codon is the selenium link because
it can direct the insertion of selenocysteine into proteins, an
alternative to its more common role as a "stop" signal. We
showed that in regions of HIV-1 that were presumed to be
inactive or non-coding, UGA codons are "conserved," i.e. found
in almost all isolates of HIV-1. Along with other structural
features we identified, these observations suggested that the
virus might encode selenoproteins in several such regions.
That was a radical suggestion because apparently no one had ever
seriously considered the possibility that viruses might encode
selenoproteins, which were believed to be very rare. Only about
five mammalian selenoproteins were known at the time, although
several more have already been found, and now some leading
researchers in this field of research believe that many more
probably exist. GPx is the prototypical selenoprotein, and is an
essential antioxidant enzyme in living systems, used to break
down harmful peroxides, to maintain cell membrane integrity, and
to generally reduce the harmful effects of reactive oxygen
species.
A deeper question is, what would a virus - say M. contagiosum or
Coxsackievirus - gain by encoding a GPx? There could be many
answers to that question. One is that it is now known that the
immune system uses free radicals as part of the process of
programmed cell death (apoptosis), which is also one of the
mechanisms used to kill off cells infected with viruses. Thus, a
viral GPx could serve a defensive function for the virus, by
countering that process and at the same time keeping the host
cell alive - again reminding us that viruses don't necessarily
want their host cells to die.
Oxidative stress is also known to activate the replication of
many viruses, especially HIV, so increasing the levels of either
a host or a viral GPx could act to inhibit viral replication.
Thus, a viral GPx could also serve as a repressor of viral
replication, similar to what I proposed for one of the
hypothetical selenoproteins in HIV, although that one is not a
GPx.
Passwater: Regarding the potential role of selenium in viruses
such as HIV, Ebola and Coxsackie, would a reduced level of
selenium-containing enzymes countering the transcription and/or
integration process contribute to the high mutation rate
characteristic of these RNA viruses?
Taylor: There are several things going on here. First, as you
mentioned, RNA viruses lack the "editing" or error correcting
enzymes characteristic of the DNA based replication machinery of
higher organisms. Furthermore, RNA is more chemically reactive
and unstable than DNA. Thus, RNA viruses are inherently more
mutation-prone even than DNA viruses, and far more than their
DNA-based hosts. This can be advantageous for a virus because by
mutating it can increase its ability to evade the host immune
system.
Thus, anything that slows down the replication rate of such
viruses will reduce their ability to mutate, because mutants are
just "sloppy copies": no copies, no mutants. That is why in the
chemotherapy of AIDS, high drug levels are used, to reduce viral
replication almost to zero: otherwise, resistant viral mutants
will rapidly emerge and the drugs won't block them. As far as
the potential role of selenoenzymes in this, we do know that
selenium somehow boosts the immune system, and cellular immunity
in particular, which should help keep viral replication in
check. But in regard to how viral selenoproteins may act, this
area is so new that we don't have any hard data; all we really
have are some "educated guesses" like the repressor hypothesis I
mentioned earlier.
Passwater: Wouldn't increasing the selenium concentration in a
virally-infected cell cause an increase in host selenoenzymes as
well as in viral selenoenzymes?
Taylor: Since the same pool of selenocysteine is involved, one
would expect that levels of both host and viral selenoenzymes
would increase if more selenium was available. This touches on
an aspect of my findings that many people have had difficulty
with from the beginning. Many people wonder: if the virus uses
or "needs" selenium, then why would taking selenium slow viral
activity - wouldn't that "feed" the virus?
The answer to this is, first of all, selenium is more essential
for us than it is for the virus. So if selenium becomes
depleted, we suffer far worse consequences than the virus.
Secondly, it also depends on how the virus uses selenium in its
selenoprotein. I explained above how a viral GPx could act to
inhibit viral replication. Thus, I have proposed that in some
cases a virus might use such a protein in a negative feedback
loop, i.e. as a repressor. That would permit the virus to
respond to conditions of low selenium in the cell - which could
be a signal of impending cell death - by replicating at a higher
rate, to "escape" from that cell.
For example, under appropriate conditions, HIV is known to
remain in cells for long periods of time, either in a latent
state or only replicating at a very low level. Selenium-based
mechanisms could help regulate that state.
Passwater: You are right about many people asking why "feeding"
the virus selenium is a good thing. They wonder if it would not
be better to starve the virus. Nutritionists and clinicians tend
to think of selenium in terms of nourishment, but in this case
you are not talking about selenium for the nourishment of the
virus. Even cancer researchers sometimes miss a similar point
when they focus strictly on nutrients and tumor status instead
of the more important question of nutrients and immune system
status Your explanation will help more scientists that are
non-virologists get the point!
In my lectures, I have used your comment about it's really not
in the best interest of viruses to kill their hosts, because the
viruses will also die. That is, unless they can jump ship (host)
by spreading to their next victim. As you said, but I want to
repeat it, the important point is that selenium is not really
feeding the virus, but is used by the virus to determine the
health of the host. If the infected cell (and thus the host) is
well nourished and not in immediate danger of dying there is no
urgent need for the virus to invade new cells.
Taylor: Perhaps it would help some of our lay readers if instead
of thinking of selenium as nourishment or food for the virus,
they would think of selenium as being part of a birth control
pill for viruses. The viruses don't need selenium for survival
so much as for growth regulation.I already explained how a viral
GPx or other selenoprotein can inhibit viral replication by
reducing oxidant tone in the cell: remember that oxidative
stress activates HIV. So a very simple analogy would be that a
viral selenoprotein could act as a viral birth control pill,
inhibiting viral reproduction when selenium is abundant. Of
course, at the same time selenium is boosting the immune system
and having other beneficial effects in the host. But when
selenium levels are too low, we not only have a weakened immune
system, the viral birth control is reduced, and the virus
replicates at higher levels. This obviously makes sense for the
virus, because this is the best time for it to break out - when
the i
mmune system is weakened by selenium deficiency. Thus, by
strengthening the immune system with high selenium/antioxidant
levels, the virus is forced to maintain a low profile. In
essence, this analogy explains what a repressor mechanism is,
using the "birth control" concept.
Passwater: Does increasing the selenium concentration in the
HIV-infected stabilize the HIV genome?
Taylor: Slowing viral replication rate reduces the opportunity
to mutate, which is what is meant by "stabilizing" the viral
genome. Since oxidative stress is known to activate HIV
transcription, selenium supplementation will reduce HIV
replication activity, simply as a consequence of increased
cellular GPx levels. That has been proved in cell culture
studies (Sappey et al. 1994). Furthermore, by protecting against
oxidative free radical damage to RNA and DNA, increased dietary
Selenium would directly reduce mutation rate. But the possible
contributions or roles of viral selenoproteins in these
processes still need to be elucidated.
Passwater: If the HIV genome is stabilized, does this give the
immune system a more steady target that it can destroy with a
"traditional" response?
Taylor: Certainly, if the ability of the virus to mutate is
impaired or slowed, it will be easier for the immune system to
neutralize it, because it will be less of a "moving target".
Passwater: Does increasing the selenium concentration in
HIV-infected cells stimulate the immune system? In uninfected
cells?
Taylor: As you know, there is a remarkably extensive body of
literature showing that dietary selenium is critical for a
healthy immune system, and that selenium potentiates various
aspects of cellular immunity, such as T-cell proliferation
responses, and the action of the cytokine interleukin 2. I think
only a part of this can be explained by known human
selenoproteins like GPx, and we really have a lot to learn about
howselenium produces its immune-stimulating effects. This
statement is supported by the fact that according to an early
study by McConnell using radio-labeled selenium in immune cells,
only about 20% of the total selenium content is contained in
GPx. So selenium is probably doing important things in those
cells that we still don't understand.
Passwater: I believe it was a 1959 study by McConnell in which
he subcutaneously injected radioactive selenium (75Se) chloride
in dogs and measured the amount of selenium incorporated into
the leukocytes. This is the first reference to selenium being
used in the immune system that I am aware of. I don't believe
that anyone has published figures changing his finding that
about 20 percent of the selenium became incorporated into the
protein fraction of the leukocytes, which indeed may be
essentially one or both of the glutathione peroxidases. That's a
good point for me to check with Dr. Orville Levander. Sorry to
interrupt, I hope it didn't make you lose your point.
Taylor: The point that I was getting to is that in HIV-infected
individuals, I would expect this role of selenium in immunity to
be at least as important as in the uninfected. In addition,
since HIV targets the immune system, an important role for
selenium in the normal immune response could also help explain
why the virus might gain something by getting directly involved
in selenium biochemistry, as I have proposed. Mimicry of host
proteins and mechanisms is a common viral strategy.
Passwater: Does increasing the selenium level in HIV-infected
cells increase glutathione or oxidized glutathione levels?
Taylor: Selenium increases GPx levels, and GPx uses glutathione
(GSH) to reduce peroxides, forming GSSG (oxidized glutathione)
in the process. So one might expect GSSG to increase when
selenium is increased. But another enzyme, glutathione
reductase, readily regenerates GSH from GSSG. So the total
amount of both forms of glutathione is what is really important.
Recently, French researchers showed that, counterintuitively,
selenium supplementation actually increases free GSH levels
significantly, which is good, because it is the reduced GSH form
that is needed for many important detoxification reactions and
free radical scavenging in the body. So some complex homeostatic
mechanisms must be involved, that act to increase total
glutathione levels when more selenium and GPx are available.
Passwater: It was recently noted that Keshan disease seems to
have a viral component rather than being strictly a
selenium-deficiency disease per se. Do you see your research as
playing a role in understanding this development?
Taylor: Actually, this link was first noted by the Chinese in
research published as far back as 1980. Coxsackie virus, a
widespread relative of the common cold virus, was isolated from
the hearts of Keshan disease victims, and was also shown to
produce heart damage in selenium-deficient mice that was
identical to that seen in human Keshan disease. I think this is
extremely significant in terms of what I am saying about HIV,
because Keshan disease is clearly a selenium deficiency disease,
apparently with a viral cofactor. And I am saying: AIDS is a
viral disease with selenium deficiency as a cofactor. And we now
have compelling evidence for virally-encoded selenoproteins in
both HIV and Coxsackie virus.
Passwater: Dr. Melinda Beck of University of North Carolina,
Chapel Hill, made an interesting observation about how a fairly
harmless strain of Coxsackie virus mutates within
selenium-deficient mice (and presumably in people as well) to
become a more harmful virus that can then spread and produce
heart damage, even in others who are not selenium deficient. Was
she aware of your research when she made her observation? How
does her finding complement your research findings?
Taylor: Dr. Beck's work is an extremely important breakthrough
in establishing the selenium-virus link. She and her
collaborator Dr. Orville Levander were working independently in
this area before I was, developing their line of research based
on the earlier Chinese observations linking Coxsackie virus to
Keshan disease. When I discovered a potential HIV-selenium link
in spring of 1994, based purely on genomic analysis of HIV, I
was unaware of their selenium work because their first paper
showing increased virulence of Coxsackie virus in
selenium-deficient mice was not yet published, although I had
seen an earlier paper they did showing a similar effect with
vitamin E.
In a subsequent paper, they showed that when passed through
selenium-deficient animals, the virus actually mutates into a
more virulent strain, that retains its virulence in
selenium-adequate animals. This has obvious implications in
regard to "emerging" viral diseases. In their published work,
Drs. Beck and Levander have focused on known mechanisms to
explain their observations, along the lines we have already
discussed: low selenium leads to weakened antioxidant defenses
and reduced immune surveillance, higher viral replication rates,
and thus to conditions favoring viral mutation. However,
particularly now that my group has demonstrated unmistakable
GPx-related sequences in the Coxsackie B virus strain that they
studied, I think they are seriously considering the possibility
of a direct virus-selenium link of the type I have proposed for
HIV. Obviously, if Coxsackie virus encodes a selenoprotein, it
would have to be involved in the mechanism underlying their
observations.
Passwater: After publishing your selenium - HIV discovery, you
proposed a possible relationship between selenium and the Ebola
virus. What did you find and why did you think to look for this
relationship?
Taylor: Coincidentally, I began to study Ebola less than a month
before the 1995 outbreak in Kikwit, Zaire that brought this
virus so drastically into the public consciousness. I did so
because of a poster presentation I had seen that spring in Santa
Fe, at a meeting of the International Society for Antiviral
Research. A Russian group presented a world map showing the
geographic areas where various hemorrhagic viral diseases tended
to occur, and I was struck by the fact that the area shown for
the filoviruses Ebola and Marburg matched a region in Africa
that I suspected might be a low-selenium region. What we found
was striking: several gene regions in Ebola contained large
numbers of UGA codons, up to 17 in one segment. We later
published a paper showing that it might be possible for Ebola to
synthesize selenoproteins from these gene regions, and proposed
a mechanism whereby this might induce artificial selenium
deficiency and contribute to the blood clotting characteristic
of Ebol
a pathology.During the revisions to the final draft of that
paper, we learned of a 1993 paper in a Chinese journal that
reported the use of selenium to treat an Ebola-like hemorrhagic
fever, with remarkable results. Luckily, the English translation
of the abstract was available. Using the very high oral dose of
2 mg selenium per day as sodium selenite, for only 9 days, the
death rate fell from 100% (untreated) to 37% (treated) in the
very severe cases, and from 22% to zero in the less severe
cases. Apparently there were about 80 people involved in this
outbreak. Dr. Hou of the Chinese Academy of Medical Sciences,
the author of this study, has since told me that he thinks more
lives could have been saved if he had been permitted to give the
selenite by injection, because in many of the more severly
affected there is so much organ damage due to internal bleeding
that they may have been unable to fully absorb or retain the
oral dose of selenium. All in all, this is the closest thing to
a curative result in the treatment of hemorrhagic fever
that I have ever heard of.
Passwater: Dr. Hou used selenite because quick and dramatic
action was required as the patients were dying in front of him.
For normal, long-range protection, organic selenium supplements,
such as selenium-rich yeast or selenomethionine, are preferred,
as discussed by Dr. Gerhard Schrauzer in the December 1991
issue, and by others as will be discussed later in this series.
How do hemorrhagic fever viruses cause hemorrhaging? Would
selenium's effect on blood clotting in the host play a role in
such diseases, or is the effect strictly an interaction with the
virus itself?
Taylor: The characteristic hemorrhaging produced by various
"hemorrhagic fever" viruses involves the production of blood
clots that ultimately block small capillary vessels, which
rupture under pressure to produce internal and even external
bleeding in severe cases. This is known as "disseminated
intravascular coagulation", or DIC. Thus, paradoxically, the
bleeding is produced by a pro-clotting mechanism, and
anticoagulants (which usually promote bleeding) have been used
to treat symptoms of the disease.
This may be very significant in regard to selenium involvement,
because the biochemical basis for an anti-clotting effect of
selenium is very well established. Severe selenium deficiency,
usually artificially induced in animals, is known to produce
hemorrhagic symptoms. Thus, the idea that hemorrhagic fever
viruses might produce a severe selenium depletion would be
consistent with the established pro-clotting mechanism of DIC.
So there may be an interaction here, where viral activity is
having a direct impact on host selenium status over the period
of one or two weeks, sufficient to cause serious pathology.
Alternatively, the results obtained in the Chinese study could
have been simply due to the anti-clotting effect of selenium, or
other mechanisms. Dr. Hou apparently decided to try the selenium
treatment because of his own theories about the involvement of
selenium in complement activation, another feature of
hemorrhagic disease. So additional studies are badly needed, to
determine what the predominant mechanism of protection by
selenium really is.
Passwater: Then do you see multiple roles for selenium against
other viruses?
Taylor: At this point, I've very optimistic about the potential
of dietary selenium as a broad-spectrum chemoprotectant against
various viral diseases. A lot of that may be entirely due to the
immune-stimulating and antioxidant benefits of selenium, but I
think that in a number of viral diseases, some degree of direct
interaction between the virus and selenium is likely to be
involved. We already have quite a few viral diseases where a
clinical correlation or definite selenium benefit has been
established: hepatitis B/liver disease, HIV/AIDS, Coxsackie
virus/Keshan disease, hemorrhagic fever, MMTV/cancer, and a
number of other animal viral diseases where selenium has been
used in veterinary practice. I also strongly suspect that
various herpes viruses will prove responsive to selenium
therapy, and the strongest case of a selenoprotein in a virus to
date is in a pox virus. So the potential scope of this
chemoprotection approach is very exciting.
Passwater: Your research is getting dramatic scientific support
at least by some researchers, what are you looking into now?
Taylor: After spending much of my efforts over the last two
years in trying to extend the scope of our HIV findings in terms
of other viruses, and trying to establish some collaborations in
order to have the implications experimentally verified, I am now
focusing on building up the capabilities in my own laboratory to
do some of the necessary experimental research. It's been slow
getting started, because we have been hampered by lack of
financial resources, and only now is the hard evidence coming in
that will enable us to convince Federal funding agencies that
this research merits support. Along with a few other labs, we
have already obtained evidence that some of the molecular
features we predicted in HIV are real. Our objective is to clone
several of the novel genes that we have found by genomic
analysis, including several from HIV and the GPx homologue from
Coxsackie virus, so the meantime we are trying to work with
clinical researchers like Dr. Marianna Baum to promote the
serious assessment of the potential benefits of selenium as a
complementary therapy in HIV disease.
Finally, I've also become very interested in the biochemical
roles of selenium in health as well as in cancer and rheumatoid
diseases, etc. My group is now engaged in a search for new
selenoprotein genes in the human genome, and we are finding some
rather intriguing things. All that I can say at this point is
that I strongly suspect that selenium is playing a role in cell
signaling and attachment - very important in the immune system -
and that selenium is more than just indirectly involved in gene
regulation. So I'm sure I'll be keeping busy well into the next
millennium trying to find out if that hunch is really true!
Hopefully our readers will be able to say they read it here
first.
Passwater: Well, we will all be looking forward to the selenium
millenium! Hopefully our readers will remember they read it here
first.
The information that you have deduced by examining genes to see
what they can make is a great help and gives great directions
for the biochemists to check out. Without this help we are more
or less left to "stumble around" trying to figure out
biochemically how selenium does all those things that our
laboratory studies show it does.
I am sure that the funding agencies will soon understand the
importance of your research. They need time to fully understand
its consequences. You have been on the program of the
International Conferences on selenium and human viruses. Now
let's see if we can get you on the programs of some of the NIH
virus researchers. Remember NIH also stands for Not Invented
Here -- and if not invented here (at National Institutes of
Health) it takes longer to get the attention of the
establishment funders. Thanks for helping us keep up-to-date on
your exciting research.