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Oregon State University

The

Linus Pauling
Institute

R E S E A R C H

N E W S L E T T E R

From theDirector

A New Twist on
Vitamin C and Beer!

Balz Frei, Ph.D.
LPI Director and Endowed ChairOSU Distinguished Professor of
Biochemistry and Biophysics

An Interview with Fred Stevens, Ph.D.
Associate Professor of Medicinal Chemistry
LPI Principal Investigatorn my last director’s column (LPI Research Newsletter
Spring/Summer 2010), I described my daily dietary
supplement regimen, which consists of:

Q. You earned your Ph.D. in The Netherlands andspent some years as a post-doctoral research
associate in Europe. You’ve been at OSU for about
eight years and with LPI for the last five years.
Is the academic research environment in Europe
much different from what you find here?
A. Of course, I’ve only seen it here at OSU as a facultyI• A multivitamin/mineral with 100% of the Daily Valueof most vitamins and essential minerals• 500 milligrams (mg) of vitamin C• 2,000 International Units (IU) (equaling 50 micrograms)of vitamin D3• 1,200 mg of fish oil• 400 mg of lipoic acid
• 1,000 mg of acetyl-L-carnitine
I also pointed out that I make sure to get 1,000 mg ofcalcium daily from my supplements and diet combined andthat I currently don’t take a vitamin E supplement becauseof concerns of an increased tendency to bleed when I takevitamin E together with a fish oil supplement.
I was pleased to see that my column inspired several
articles in the popular media, including an upcoming article
in Vogue magazine. My column also elicited feedback frommy faculty colleagues and several LPI supporters around thecountry. One loyal donor from New York wrote me, “I doeverything you do. So maybe that’s why I just passed my95th birthday.” He continued, “Two things that I do thatyou left out, [but] I’m sure that you will add along the way:
1. Resveratrol 2. Coenzyme Q10.” He was not the only LPI
donor who asked about those two supplements.

member. Here, we’re much more focused on grant writing
and getting money for research, while in Europe moretime is spent on the research itself and writing papers.

Q. How is academic research funded in Europe?
Are there government agencies to which you apply
for funding?
A. In The Netherlands, the Ministry of Education allocates
research funds to the universities, and they distribute thatto the departments. Every department has state-funded
professors, lecturers, technicians, and graduate students.
At Oregon State University, only professors and instructors
have state-funded positions. In The Netherlands there
are opportunities to apply for national or European
grants that are generally smaller in size.

Q. What do you like to do when you’re not working
in the lab?
A. I like to swim every day.
Q. What’s your position at LPI?
A. I’m a Principal Investigator, and my academic home is
the Department of Pharmaceutical Sciences in OSU’s
College of Pharmacy.

In addition, Dr. Maret Traber, LPI Principal Investigatorand one of the world’s foremost authorities on vitamin E,
wasn’t quite happy that I preferred fish oil over her favorite
vitamin. On the other hand, Dr. Donald Jump, an LPI

Q. You also serve as co-director of the Biomolecular Mass
Spectrometry Core Lab. What does that lab do?
A. That lab provides mass spectrometry services for OSU.

continued on page 2

continued on page 3

I provide expertise and instrumentation for analysis of— DESIGNATED BY THE NATIONAL INSTITUTES OF HEALTH AS A —Center of Excellence for Research on Complementary and Alternative Medicine

Continued from cover — From the Director
Principal Investigator who is doing cutting-edge researchon the biology and health effects of omega-3 fatty acids,
including fish oils, didn’t object. So, in this column, let me
further comment on those three supplements—vitamin E,
resveratrol, and coenzyme Q.
As you may know, vitamin E has taken a beating lately
in both the scientific literature and popular press.
Numerous large, randomized, placebo-controlled trials(RCT) of vitamin E supplementation for the prevention ortreatment of heart disease or cancer have shown mixed andoverall disappointing results. Some “meta-analyses” evensuggested that vitamin E supplements may increase therisk of dying! Hence, the medical community, with a few
exceptions, has all but dismissed any health benefit ofsupplemental vitamin E. However, these RCT, which areconsidered “the gold standard” for showing efficacy andsafety of a medical drug, are far from being the ideal
approach to test the efficacy and safety of micronutrient
supplements like vitamins and essential minerals.
For example, while drugs are being recognized by the
body as foreign substances (“xenobiotics”) that are rapidly
metabolized, detoxified, and excreted, vitamins are essential
for life (“vita” meaning life in Latin). Humans have
evolved specific mechanisms to absorb and transport theseessential nutrients to target cells and tissues for use in
enzyme reactions and other biological functions. This alsomeans that every person has been “exposed” to thesemicronutrients through their diet over their lifetime, which
is not true for synthetic drugs that are only taken as partof the study. Therefore, RCT of micronutrients are notcontrolled: while the investigators give a placebo pill to the“control” group, all subjects in this control group havesubstantial levels of the vitamin to be tested in their bodies
from the outset and throughout the course of the study!
This severely limits the statistical power of the trial. For
these and other reasons, the deck is stacked heavily against
showing an effect of vitamin supplements in RCT.
A much better approach to evaluate the possible healthbenefits of vitamins is to look at the totality of evidence—
test tube, cell culture, and animal studies, as well as
epidemiological studies (human population studies) otherthan RCT. This totality of evidence shows that vitamin E
acts as an important, fat-soluble antioxidant in our bodies
and is very likely to have benefits in reducing the risk of
diseases that have oxidative stress as a contributing factor,
such as heart disease, ischemic stroke, Alzheimer’s disease,
and, possibly, certain cancers and Lou Gehrig’s disease.
Therefore, I firmly stand behind LPI’s recommendation totake a daily supplement of 200 IU (133 mg) of natural
source alpha-tocopherol (d-alpha-tocopherol) with a meal.
Coenzyme Q is often taken for two purposes: 1) tostrengthen mitochondria, the “power plants” in our cells,
and enhance energy metabolism; and 2) as an antioxidant
to protect cell membranes and lipoproteins against
oxidative damage. In fact, I co-authored two papers 20

2

Fall/Winter 2010

years ago in Proceedings of the National Academy of
Sciences USA showing that coenzyme Q is an effective fatsoluble antioxidant and protects low density lipoprotein—
the “bad cholesterol” contributing to heart disease and stroke––more efficiently against oxidative damage than vitamin E.
Coenzyme Q, unlike vitamins, is not an essential nutrient
because it is synthesized in our bodies. A major problem withcoenzyme Q supplements is that they are poorly absorbed,
although some formulations are available that have increased
bioavailability. It is also unclear whether supplemental
coenzyme Q reaches its target tissues in the body, such asmuscles, heart, and brain, especially in healthy individuals.
There is some evidence that coenzyme Q supplementation
is useful as an adjunct to conventional drug therapy forcongestive heart failure and may help in the treatment ofother cardiovascular diseases and certain neurodegenerative
diseases, such as Parkinson’s or Huntington’s disease. It’s also
possible, but not proven, that heart disease patients taking
cholesterol-lowering statins may benefit from coenzyme Q
supplementation. Statins are known to inhibit coenzyme Q
synthesis in the body because they target the same pathway ascholesterol synthesis. Because of the limited overall evidence
for benefit in healthy individuals, its low bioavailability, andthe relatively high cost, LPI does not recommend regularcoenzyme Q supplementation for healthy individuals. Certain
subpopulations with specific diseases, older people, andindividuals taking statin drugs may derive some benefit fromcoenzyme Q supplements.
Finally, resveratrol has been one of the hottest topics
among the health-conscious public, as attested by thefact that the resveratrol article on LPI’s Micronutrient
Information Center (http://lpi.oregonstate.edu/infocenter/
phytochemicals/resveratrol) is visited over 50,000 times eachmonth. As we explain on that Web site, there is intriguing
evidence that resveratrol “can inhibit the growth of cancer
cells in culture and in some animal models” and may mimic
caloric restriction and extend “the lifespan of yeast, worms,
fruit flies, fish, and mice fed a high-calorie diet.” However,there is very little evidence for any health benefits ofresveratrol supplements in humans, let alone evidence that it
extends lifespan. The LPI research focus has been more on
healthspan than lifespan, as we believe it is more importantfor people to attain a healthy old age than just a long life.
Commercially available resveratrol supplements
contain doses that are hundreds or thousands oftimes higher than the amount naturally present
in red wine or grapes. We don’t know if
taking such large doses of resveratrol
over long periods of time is safe. Hence,at our current state of knowledge, therisk/benefit ratio seems unfavorable.
LPI does not recommend resveratrol
supplements, nor do I take them
personally. I prefer to get myresveratrol the natural way.
So, here’s to your health! LPIContinued from cover — Interview with Dr. Fred Stevens
small organic molecules, which includes metabolites.
We analyze metabolites made from lipid peroxidation
products and xenobiotics. We do a lot of work forpeople in the Colleges of Pharmacy and Veterinary
Medicine, analyzing drugs and case studies.

Q. You worked for many years on a phytochemicalcalled xanthohumol found in beer. What is
xanthohumol and what does it do in cells?
A. Xanthohumol is a flavonoid found in hops. We’ve
known about it for a long time, but it never received any
attention from beer brewers because it has no taste.
I got interested in xanthohumol back in 1995 when
I became a post-doc at Oregon State University withProfessor Max Deinzer. We were investigating thechemistry of hops and focused on xanthohumol, which
we were able to isolate. Professor Don Buehler, Val
Miranda, and I investigated the activity of xanthohumolin cancer cells and found that it induces phase 2 enzymes—enzymes that detoxify carcinogens. That is good forcancer chemoprotection. We also found that xanthohumol
inhibits phase 1 enzymes that activate pro-carcinogens.
So the effect is two-fold: xanthohumol prevents activationof pro-carcinogens into carcinogens by phase 1 enzymes
and helps detoxify carcinogens by the phase 2 process.
We can clearly say that xanthohumol is a cancer
chemoprotective compound in cell culture.

Q. One problem with the cell culture model is that it
doesn’t necessarily predict what will happen in
the body because compounds need to be absorbed
into the blood stream to have many physiologicaleffects. Have you studied the bioavailability ofxanthohumol—how much actually gets into theblood stream?
A. We have measured pharmacokinetics in a handful ofpeople and found that xanthohumol is absorbed andmay be distributed to the tissues, which seem to holdonto it for a long time. It has a long half-life in the
body. Although the plasma levels are relatively low,tissue levels may be much higher. Low plasma levels
don’t necessarily imply a lack of biological activity.

Q. Does xanthohumol act as an antioxidant in
the body?
A. It has antioxidant activity in vitro. We don’t thinkthat it functions as an antioxidant in the body.

Q. Is xanthohumol found in other dietary plants
or in lagers and wines?
A. It is found in any beer that is produced from hops
but not in dietary plants. It’s not found in beers thatare made from hop extracts.

Q. One of the hop flavonoids you studied,
8-prenylnaringenin, is a potent phytoestrogen.
How may that affect health?
A. Prenylnaringenin was identified as a metabolite ofisoxanthohumol, which is the isomer made from
xanthohumol when you brew the beer. However, thelevel of prenylnaringenin in beer is very low, and it’svery doubtful that the low amount in beer would be
estrogenic in people. In the last couple of years, studies
have shown that some people have certain microorganisms in the gut that are able to convert
isoxanthohumol into prenylnaringenin. Xanthohumol
supplements in those people may be problematic,
but the amount in beer is not a concern.

Q. Is there any way to determine which people havemicroorganisms that convert isoxanthohumol toprenylnaringenin?
A. There is no easy test to identify these people.
Q. How might xanthohumol help prevent
prostate cancer?
A. We published a paper with Emily Ho, another LPI
Principal Investigator, showing that xanthohumol
interferes with NFκB signaling. NFκB is a protein andmaster switch for the regulation of about 400 genesthat are involved in inflammatory processes.
Xanthohumol binds to a certain chemical group in a
structural subunit of NFκB and prevents its signaling,
thereby blunting or reducing the inflammatory
response. NFκB-driven inflammation is an important
process in the development of prostate cancer.

Q. You studied another kind of flavonoid,
proanthocyanidins. What foods contain these?
A. Virtually all plants make proanthocyanidins, also
called condensed tannins. They are found in hops,
grapes and their seeds, apples, cocoa, tea, and many
fruits. Anything that has an astringent taste probably
contains a lot of proanthocyanidins.

Q. How do proanthocyanidins affect the risk forcolorectal cancer?
A. We found that proanthocyanidins kill cancer cells in
vitro by producing hydrogen peroxide. Bioavailability,
or absorption into the blood stream, is not an issue
because the colorectal cells would be directly exposed
to ingested proanthocyanidins.

Q. Why are xanthohumol and proanthocyanidins
synthesized by plants?
A. Well, a lot of phytochemicals are defense chemicals
against herbivores. Of course, unripe fruits contain alot of tannins and are not palatable to animals, so they
don’t eat them until the fruit is ripe. Then the animals
consume the fruit and disperse the seeds, which helps
ensure survival of the plant species.

Q. For the last half-dozen years, you have worked
on reactions between vitamin C and rancid fats,or lipid peroxidation products, also called LPO
products. How does vitamin C react with these?
A. Well, this is a difficult problem. When fats get oxidized,
they make degradation products known as reactive
aldehydes.

continued on page 4

The Linus Pauling Institute3

Continued from page 3 — Interview with Dr. Fred Stevens

Q. Does that happen in the body?
A. Yes, we have lots of evidence that these aldehydes are
made in the body. Vitamin C can react in vitro withthese compounds to make what we call ascorbylated
lipids. This has been shown for a very small lipid
peroxidation product called acrolein, which reacts withvitamin C in cultured cells. This is an important finding
because it shows that vitamin C can compete with awell-known pathway called glutathione conjugationthat helps get rid of toxic products. At first we were
not very successful in finding these LPO products.
It now appears that the ascorbylated aldehydes get
further metabolized. We have identified one metabolite
and want to find out if it is the final end product orgets further modified. Once we have clearly identified
the end products, we will try to determine if thisprocess happens in the body.

Q. What is the physiological significance of LPO
products? How are they detrimental to health?
A. Not all of them are bad. Prostaglandins are enzymatic
breakdown products of lipid hydroperoxides.
Prostaglandins are ubiquitous and have very importantfunctions, including the regulation of platelet activity
and inflammation. On the other hand, nonenzymatic
lipid perioxidation generates reactive aldehydes thatcan react with DNA in a nonspecific manner. This cancause DNA mutations that could lead to cancer.
Aldehydes can also react with proteins, including
enzymes, in a nonspecific manner, causing damage thatcan lead to cellular dysfunction. For example, elevatedlevels of the LPO product, 4-hydroxy-2-nonenal(HNE), have been associated with the development
and progression of Alzheimer’s disease.

Q. Can LPO products be used as biomarkers tomeasure oxidative stress in the body?
A. We have done three studies on this. The first was a
study where we exposed rats to carbon tetrachloride,
which is a strong inducer of lipid peroxidation andoxidative stress. We then looked in the urine formetabolites of HNE and a related product called
4-oxo-2-nonen-1-ol (ONO). We were the first group tofind evidence for in vivo production and metabolism
of ONO. It certainly has value as a biomarker ofoxidative stress in rats. In the second study, we usedsmokers as a model of chronic oxidative stress inhumans. We found that the smokers had higher
levels of LPO products, but the differences were notstatistically significant because people vary widely inlevels of oxidative stress. Then we looked at smokers
who stopped smoking and found that smoking
cessation results in a substantial decrease in thesebiomarkers. With LPI’s Maret Traber, we wanted toknow if vitamin C supplementation would affect these
new biomarkers. Using mass spectrometric analysis of
the subjects’ urine, we found that vitamin C supplementation decreases these HNE and ONO metabolites.

4

Fall/Winter 2010

Q. Would these be better biomarkers of oxidative
stress than F2-isoprostanes or other standard
biomarkers?
A. The biomarkers that we measure are present in muchhigher concentrations, so that’s a benefit analytically.
Also, some of them are very stable because they havebeen fully oxidized—they are final end products easy towork with. Although this work is still in the very earlystages, we can say that in the study we just completed
vitamin C supplementation leads to a decrease in HNE
metabolites, whereas F2-isoprostanes did not change.

Q. You have studied a ubiquitous chemical called
acrolein that is formed by cooking food,hydrocarbon combustion, cigarette smoking,and other processes. What does acrolein do in
the body?
A. HNE is the prototypical lipid oxidation product, but
acrolein can also be formed from lipid peroxidation.
Its major source is smoking. A study a couple of years
ago claimed that acrolein—not tar—is the carcinogenic
compound in cigarette smoke. That, of course, received
a lot of interest in the media.

Q. What epidemiological evidence links acrolein tolung cancer?
A. Acrolein is a very small molecule and a volatile substance,
so when you cook with vegetable oils, it’s probably
present in the kitchen air. In Hong Kong, wok cooking
in unventilated kitchens, not smoking, is thought to be
the cause of the high rate of lung cancer in women.

Q. How does vitamin C affect acrolein?
A. Acrolein is a reactive aldehyde that can damage
bio-molecules. Vitamin C can function chemically as
an electron donor. Acrolein is an acceptor, and they
react with each other to form an adduct, ascorbylated
acrolein. It is a very efficient reaction and is easily donein the test tube. We examined the crystal structure ofascorbylated acrolein with a chemist here at OSU. Since
vitamin C adduction to acrolein happens so easily invitro, we think that this reaction may have biologicalsignificance in vivo. Of course, the metabolism of thiscompound needs to be further studied. When we started,
Nicholas Kesinger, my graduate student, challenged
cells with acrolein but didn’t find anything unusual.
That was very disappointing because we had hoped todetect evidence of the chemical reaction we expected.
Then we added synthetic ascorbylated acrolein to cells,
and it disappeared, although we could easily measure
it in a buffer solution. So then we started thinking
that ascorbylated acrolein might be metabolized and
we discovered that it follows a very unusual metabolic
pathway. That was the main finding of Nick Kesinger’s
Ph.D. project that he completed with me in LPI.

Q. So vitamin C forms an adduct with acrolein thatthen further degrades through metabolic processes
in the body, rendering the acrolein harmless.
A. Right.

Q. Have reactive aldehydes been found to cause
diseases in humans?
A. A possible example is Alzheimer’s disease. There are a
lot of studies showing the involvement of HNE in thepathogenesis of Alzheimer’s disease, and, as I mentioned,
acrolein is involved in lung cancer in smokers.

Q. How does HNE contribute to Alzheimer’s
disease?
A. Scientists think that HNE damages proteins that areimportant for prevention or delaying onset of thedisease. For example, HNE can inactivate an enzyme
called neprilysin that breaks down the amyloid beta
plaques in the brain of Alzheimer’s patients.

Q. You’ve described a reaction between vitamin C
and certain phytochemicals that you callascorbylation, which you’ve already discussed.
How is this relevant to health?
A. This is very controversial because many scientists claimthat electrophilic products—chemicals attracted toelectron donors—in the body interact with glutathione.
The idea that vitamin C plays a role as a nucleophilecame from nature. A nucleophile has an excess ofelectrons—it’s an electron donor—and combines with
substances that have a deficiency of electrons to makean adduct. About 10 years ago, I isolated a natural
product from henna, which contains a dye that’s anaphthoquinone. The naphthoquinone reacts readily
with vitamin C in the plant material when you crush
it to make the dye. That’s how I found my firstascorbylated natural product. So I thought, if thisreaction happens so readily in plant material, it musthave some biological significance. Then we searchedmore carefully in the plant kingdom for the specificstructural moiety allowing the ascorbylation reaction,and to our surprise, we found 33 natural products that
had that moiety. In most cases, the authors were noteven aware that they had a vitamin C adduct.

Q. Are these adducts formed only in plants, not in
the body during digestion or metabolism?
A. Right. These are true natural products. A famous
example is ascorbigen, which is an indole-3-carbinol
metabolite with vitamin C found in cabbage. There
are also tannins that contain the vitamin C moiety.
For example, a tea flavonoid—epigallocatechin gallate
or EGCG—has been found in an ascorbylated form.
There are many, many examples. There must be areally significant reason for this reaction in nature,and that is what we are trying to understand.

Q. Those ascorbylated compounds occur in plants
and, of course, may or may not have much
relevance to human physiology or health.
A. Right. Plants make vitamin C for their own health;they don’t make it just for us! I don’t know therelevance of ascorbylation for plants, but if it reduces
the reactivity of waste products in the human body,then it could be considered a detoxification pathway.

Q. Do ascorbylated compounds contribute to the
antioxidant capacity of food?
A. No, because the moiety has been totally modified.
Vitamin C has a double bond and two hydroxyl groups.
Basically, it functions as an antioxidant because it’s aone-electron donor. The ascorbylation reaction is a
two-electron reaction, and then the double bond in thevitamin C molecule disappears, and the antioxidant
activity is lost.

Q. Where is your research headed in the next
few years?
A. We will continue to study the interaction between
vitamin C and reactive aldehydes. There are multiple
ways in which vitamin C may be helpful in unexpected
ways. Last year we compared levels of protein adduction
by HNE in human monocytes in vitro with and without
vitamin C. We found that vitamin C reduced the levelof protein adduction by HNE by 30%. We couldn’t
attribute all of that to the formation of the ascorbylated
products because we didn’t know about the metabolism
at the time. Nevertheless, there must be other mechanisms
by which vitamin C protects proteins from damage by
these reactive aldehydes. This could be very important
for a number of diseases. We’re working on cardiovascular disease, and in the future we will determine
the effect of vitamin C in protecting proteins that areimportant in cardiovascular health.

Q. What kinds of proteins?
A. One enzyme we are studying is aldehyde dehydrogenase.
This is an enzyme that metabolizes HNE, but HNE canalso damage the enzyme. Of course, if HNE damages
the enzyme, then HNE itself cannot be metabolized andmore and more of it is accumulated and creates more
and more damage. If vitamin C could protect the
enzyme, then HNE could be properly metabolized,
and there would be less damage.

Q. LPI will move into our new building, the Linus
Pauling Science Center, next summer. To which
research cluster will you belong?
A. I will be with Balz Frei, Maret Traber, and Don Jump
in the cardiovascular and metabolic diseases group.

Q. You must be looking forward to that.
A. I’m very excited! LPI

The Linus Pauling Institute5Induction of Apoptosis
in Cancer Cells
Siva Kumar Kolluri, Ph.D.
OSU Assistant Professor
Department of Environmental andMolecular Toxicology
Summary: To effectively treat cancer, we want to protect
normal cells and selectively kill cancer cells. A protein called
Bcl-2 regulates apoptosis or cell death. An abundance of
Bcl-2 produced in cancer cells prevents apoptosis. Preventionof apoptosis promotes cancer cell growth. Another protein
called Nur77 can interact with Bcl-2 and convert Bcl-2 froman anti-apoptotic to a pro-apoptotic protein in cancer cells.
We discovered that small fragments of Nur77 (peptides, orgroups of amino acids that make proteins) could also interact
with Bcl-2, leading to the death of cancer cells.
Damaged cells in the body are eliminated through aprocess involving cell suicide known as apoptosis. Since
apoptosis normally eliminates cells with increased malignant
potential, such as those with damaged DNA or aberrant cell
cycling, inhibition of apoptosis is highly important to tumor
initiation and progression. All cells contain both pro-deathand pro-survival proteins that regulate the process of cell
apoptosis. These pro-survival proteins are abundantly
expressed in cancer cells, which help them to thrive and resist
elimination upon treatment with anti-cancer drugs. Bcl-2—anacronym for B-cell lymphoma 2—is one such survival proteinthat is overexpressed in a variety of cancers, including leukemia
and lung, liver, gastric, ovarian, prostate, and breast cancers.
Members of the Bcl-2 family of proteins modulate
apoptosis in different cell types in response to various stimuli.
Some of these members, such as Bcl-2 and Bcl-XL, act toinhibit apoptosis (anti-apoptotic), while others, such as Bax,
Bak, Bid, and Bad, promote apoptosis (pro-apoptotic). All
members of the Bcl-2 family possess at least one of the four
structural domains called Bcl-2 homology (BH) domains.
Domains are discrete, stable components of protein structurethat combine in different ways to make different proteins.
Proteins that contain only one BH domain (BH3) are proapoptotic. Interestingly, anti-apoptotic Bcl-2 members containthis BH3 domain along with three other BH domains (1, 2
and 4). To prevent apoptosis, anti-apoptotic members bindpro-apoptotic members containing only the BH3 domain, andwhile this occurs in normal cells, a significant upregulation of
Bcl-2 in cancer cells disrupts the normal balance, allowing
cancerous cells to survive.
Nur77 is a protein that belongs to the superfamily of
nuclear receptors that controls gene expression in cells.
Nur77 has the capacity to not only regulate gene expression
but also to induce apoptosis. Importantly, the apoptotic effectof Nur77 family members is clinically relevant, since theexpression of the Nur77 subfamily member Nor-1 improves
survival in diffuse, large B-cell lymphoma patients treatedwith chemotherapeutic drugs. Gene expression profiles havealso revealed that downregulation of Nur77 expression isassociated with metastasis of primary solid tumors.

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Fall/Winter 2010

We had previously demonstrated a new paradigm incancer cell apoptosis, whereby Nur77 moves from the cell’s
nucleus to its mitochondria, where it interacts with Bcl-2,
converting this normally anti-apoptotic protein into a
pro-apoptotic protein that induces cell death. While trying tounderstand this unexpected phenomenon, we discovered that
Nur77 causes an alteration in the Bcl-2 structural conformationthat exposes its hidden pro-apoptotic BH3 domain.
In collaboration with Drs. Xiao-kun Zhang, Arnold
Sattherthwait, John Reed, and other colleagues at the
Sanford-Burnham Medical Research Institute, we discoveredthat even short protein fragments or peptides from Nur77’s
Bcl-2 binding region are able to induce the same conformation
changes in Bcl-2 that Nur77 induces. We found that the
Nur77-derived short peptides bound to Bcl-2 and exposed
its BH3 domain, which allowed for Bcl-2 to activate two
pro-apoptotic proteins, Bax and Bak, to initiate apoptosis.
Importantly, the altered Bcl-2 also neutralized the antiapoptotic activity of other Bcl-2 family members. We thenfound that these peptides induced apoptosis in cancer cells
in vitro and suppressed the growth of human cancer cells
explanted in mice. To further confirm this relationship,
we established that the pro-apoptotic activity of the Nur77
peptides was dependent on Bcl-2 expression.
mitochondrion
Bcl-2

Bcl-2

Nur77
Bak
Nucleus

Bax Nucleus

Bak

Bax

Nucleus

CELL
DEATH

How Nur77 initiates apoptosis in cancer cells

A majority of solid tumors are protected from apoptosis
by overexpression of Bcl-2. Accordingly, there have been
efforts in the last few years to identify compounds thatneutralize Bcl-2’s anti-apoptotic functions to make cancer
cells more susceptible to chemotherapeutic drugs orcompounds. This has led to the development of approaches
that either decrease Bcl-2 protein expression or neutralize thesurvival functions of Bcl-2 with small molecules. However,neutralizing Bcl-2’s normal anti-apoptotic/pro-apoptotic
function alone may not be sufficient, since other anti-apoptotic
proteins must also be inhibited for the therapeutics to beeffective. Importantly, our studies have established that
Nur77 peptides or small molecule mimetics not only inhibit
Bcl-2 survival function but also neutralize other Bcl-2 survival
proteins by altering Bcl-2 conformation. This will likely havetherapeutic value in treating a variety of cancers.
Pilot project funding from LPI helped us to conduct theexperiments that reveal the mechanism of cell death inducedby the converted Bcl-2. Furthermore, the LPI pilot projectaward helped us to establish assays to potentially identify
additional compounds that convert Bcl-2 from a cell protector
to a cell killer. This research helped to secure additional
funding from the Breast Cancer Research Program of the
Department of Defense. LPIDevelopments
Michele Erickson
LPI Director of DevelopmentIt is with great enthusiasm and commitment that
I introduce myself as the new Director ofDevelopment for the Linus Pauling Institute. It’s anhonor for me to work on behalf of LPI’s Director,
Balz Frei, and all the other investigators who are
conducting such innovative and important nutrition
research. I am eager to work with all of you who
have given so much to ensure the outstanding
reputation and scientific progress of LPI.

A Vision to Expand LPI’s Healthy
Aging Program
The Linus Pauling Institute has been conducting
research and providing education for nearly 40 years
to help people everywhere achieve healthy, productive
lives and to prevent disease through diet, dietary
supplements, and lifestyle. LPI’s internationallyrecognized expertise in orthomolecular or preventive
medicine and world-class faculty have positioned it
as a leading international research institute. Donors
like you propelled this work by contributing morethan $33 million to the Linus Pauling Institute in thelast few years, reaching our goal to fund constructionof the new Linus Pauling Science Center and initiating
the creation of LPI’s Healthy Aging Program byendowing a Chair for the program director andrecruiting the first of three additional faculty
to work on age-related health issues, such as
declining immune function and Alzheimer’sor Parkinson’s disease.
Increasingly, people are turning to the Linus
Pauling Institute for expert, science-based advice on
the “protect and prevent” role of micronutrientsand other dietary factors vital to healthy aging.
When fully realized, LPI’s vision of five world-classPrincipal Investigators leading the Healthy Aging
Program’s research efforts, leveraged by a dedicatedteam of graduate students and post-doctoral fellows,
will allow us to make tremendous strides. Alreadydesignated by the National Institutes of Health(NIH) as one of the nation’s first two Centers of
Excellence for Research on Complementary andAlternative Medicine, the Linus Pauling Institute will
be highly competitive for NIH grants and influential
as advisors on national committees shaping future
research and recommendations for improving healthand wellness in the U.S.

Donor Contributions Lead to Success
The advancement of the Linus Pauling Institutehas been extraordinary. Construction of the Linus

Pauling Science Center is a visible and tangible
indication of LPI’s growth and will enhance scientificresearch, extramural funding, and public education
to help use this knowledge for people to live
healthier lives and reduce suffering. LPI’s recent
accomplishments:• Linus Pauling Science Center construction(Grand Opening summer 2011)• The J. Burgess and Elizabeth B. Jamieson
Endowed Chair in Healthspan Research• Two new Principal Investigators in immunosenescence/vitamin D research and cancer
chemoprotection, respectively• Funding for another new Principal
Investigator in the Biochemistry of Aging andcommencement of an international search• Expansion of LPI’s online Micronutrient
Information Center, which receives over
25 million hits every year
While these accomplishments are extraordinary,
it is the annual gifts from dedicated donors likeyou who keep the important day-to-day researchgoing. Thank you for the vital gifts you have madeto LPI to sustain our Research Innovation Fund.
Please continue your essential support. Together,
we can help people everywhere live longer andhealthier lives.
I hope to be able to meet with many of you
in person and hear about your experiences.
Please don’t hesitate to contact me in the office at541-737-3744 or by email at Michele.Erickson@
oregonstate.edu if I can be of assistance in any way.
P.S. Construction remains on schedule for theInstitute’s new home, the Linus Pauling Science
Center (see http://webcam.oregonstate.edu/lpsc)!
There’s still time to name a room by designating
LPI in your estate plans. For information, pleasecontact me by phone or email. LPI

LPI is grateful for thebequests
we have received fro
m thefollowing friends thispast year:
John F. Holterhoff
Nancy J. Bradford
Jean S. White
Gerald D. Carney
Mavis E. DeCius

Grace Telenius Davis
Helen P. Rumbel
Nancy Ann Finke Bower
Mildred G. Mayne
William R. Town
LPI

The Linus Pauling Institute7

The LPI Fitness& Nutrition Studyin Children
Simone Frei, MPH, MA
LPI Program CoordinatorChildhood obesity has become epidemic in the UnitedStates. Results from the 2007-2008 National Healthand Nutrition Examination Survey estimate that 16.9%
of children and adolescents aged 2-19 years are obese
compared to only 5% in 1971. According to the 2007
National Survey of Children’s Health, obesity rates for
10- to 17-year-old children range from 9.6% in Oregon
to 22% in Mississippi.

suggested that “multivitamin/mineral supplementation toincrease micronutrient intake to recommended levels is a
prudent, inexpensive, and convenient way to improve thepublic’s health status.”
Vitamin D deficiency in American children is becoming amajor concern. While parents and pediatricians may haveassumed that children are getting enough vitamin D fromsunshine, vitamin D-rich foods, and vitamin D-fortified
milk, a study published in 2009 found that 70% of children
have inadequate vitamin D levels and nearly 10% aredeficient. Most people living above 40 degrees latitude do
not obtain enough vitamin D from about mid-November
to early March. People with dark-colored skin have asignificantly lower ability to synthesize vitamin D fromsunlight, as do the elderly, and obesity increases the riskof vitamin D deficiency because these individuals cannot
easily access the vitamin D stored in their body fat.

Childhood obesity is associated with many health risks,such as pediatric hypertension, type 2 diabetes, orthopedic
complications, and impaired mobility, and can result in
psycho-social consequences like low self-esteem, social
isolation, and discrimination. In addition, long-term studies
have shown that obese children are likely to become obese
adults. Most experts agree that physical inactivity and apoor diet are the root causes of obesity and that there is a
widespread need to promote regular physical exercise andbetter eating habits among children. Clinicians and publichealth officials recommend that children engage daily in
60 minutes of moderate to vigorous physical activity, suchas brisk walking, running, cycling, or playing outdoors.
However, opportunities for children to be physically active
during school days have decreased in most schools acrossthe United States. Additionally, time spent on sedentary
activities like watching TV or playing computer and othervideo games is increasing.

New evidence shows that vitamin D deficiency may not
only be associated with rickets and osteoporosis but alsowith muscle pain and weakness; cancers of the breast,
prostate, and colon; high blood pressure; heart disease;multiple sclerosis; rheumatoid arthritis; osteoarthritis; type
1 and 2 diabetes; irritable bowel syndrome; and Crohn’sdisease. Research by LPI’s Dr. Adrian Gombart has shownthat vitamin D also plays a critical role in immune function
by enhancing the production of a protein in the body thatcan fight viruses and bacteria (see the Spring/Summer 2010
LPI Research Newsletter). Hence, vitamin D plays animportant role in preventing upper respiratory tract
infections, tuberculosis, and other viral and bacterial
infections that occur during the flu season. Based onthese findings, the Linus Pauling Institute recommends
that children supplement their daily diet with 1000 IUof vitamin D to achieve good health.

Several surveys indicate that many children do not obtainan adequate intake of many vitamins and minerals in theirdiet that are essential for good health and disease prevention.
The Multivitamins & Public Health Workshop in 2003

During the 2009-2010 school year, we implemented a
program to increase fruit and vegetable consumption andphysical activity among elementary school children in the

The LPI Fitness & Nutrition Study

Recognition for LPI Staff and Faculty

Scott Leonard

Emily HoAt the recent OSU University Day, two members of LPI were recognized
for their outstanding achievements. Scott Leonard of Dr. Maret Traber’s
lab in LPI was honored with the Outstanding Faculty Research AssistantAward, which recognizes “scholarly achievement and a level of innovationand effort that far exceeds expectations” and truly exceptional
performance. LPI Principal Investigator Dr. Emily Ho was given thePromising Scholar Award, which recognizes “outstanding scholarly
activity that represents significant intellectual work validated andcommunicated through peer review.” She will hold the title of“Promising Scholar” for 2011.
The Linus Pauling Institute8

We set up a point system to assess study compliance.
Each student could collect a maximum of 9 points per
week (3 points each for walking/running, fruit snack,and fruit and vegetables for lunch); a minimum of 6
points per week was required (66% participation) to beconsidered compliant and remain in the study. Incentives,
such as T-shirts and Frisbees, were given to enhancecompliance. We measured the students’ height andweight and calculated their body mass index (BMI)
three times during the school year and asked them to fillout a validated Food Questionnaire, Physical Activity
Survey, and Pediatric Quality of Life Questionnaire
twice during the school year.
One hundred and thirteen students, or 52% of the 219
students in grades 3-5 at the school, voluntarily enrolled
in the study. Interestingly, 71% of all girls in grades 3-5
enrolled, but only 37% of boys enrolled. Of the 113
enrollees, 85 completed the study, corresponding to 75%
compliance. Among these 85 students, the level ofparticipation differed significantly between grades—3rd
graders had a higher participation level (84%) than the
4th and 5th graders (70% and 69%, respectively). The
level of participation for all grades decreased from 82%
at the beginning to 70% at the end of the study. Further
analysis showed that the decline in participation was due
to a decrease in walking/running during recess, whereas
fruit and vegetable consumption remained unchanged.
This declining participation in physical activity wasobserved for all grades, but the 3rd grade students
maintained a significantly higher level of participation
than the 4th and 5th graders throughout the study.
The calculation of body mass index (BMI) for
children, unlike adults, takes into account the child’s
gender and age and is expressed as a percentile. A BMI
below the 85th percentile indicates a healthy weight;
overweight is defined as a BMI between the 85th and95th percentile; and obese is a BMI higher than the 95th
percentile. Among our study’s students, the numberof overweight and obese students decreased with acorresponding increase in students with a healthy weight(see figure at top right). This reduced prevalence ofoverweight and obesity was mainly attributable to adecrease in the mean BMI of the children in the three
3rd grade classrooms and in one 5th grade classroom.
The mean BMI of the 3rd graders decreased from the62nd to the 51st percentile and for the 5th graders fromthe 71st to the 64th percentile. These four classrooms
also had the highest number of study participants,

9

Fall/Winter 2010

indicating that the higher the participation per classroom,
the greater the decrease in BMI.
Interestingly, we observed a similar trend in BMIchange among the non-study children in all 3rd gradeclassrooms. These results probably reflect teacher
support for the study. It is likely that support by theseteachers had an impact on the health behavior of theirstudents regardless of the students’ participation in
the study.
Fall 2009

Spring 2010

Number of Children
Overweight or Obese(>85th Percentile)

21 (28%)17 (23%)

Number of Children
with Healthy Weight(<85th Percentile)

54 (72%)58 (77%)

BMI at the beginning and end of the study(Number of children = 75 for whom we had complete BMI data)

Fruit/Fruit Juice and Vegetable Intake
The Food Questionnaires revealed that the fruit/fruit
juice and vegetable intake did not differ between girls andboys (see figure below). The children consumed about
half a cup more fruit than recommended by the U.S.
Department of Agriculture. However, reported vegetableconsumption was significantly below the recommended
intake of 2.5 cups. The increased fruit intake is likely due
to the fresh fruit offered for morning snack. The reported
fruit and vegetable intake did not change significantly
from the beginning to the end of the study. The Food
Questionnaires also revealed that most children did not get
the recommended amounts of vitamins A and E, calcium,and magnesium from their diet, and many also did not
get enough vitamin K, iron, and zinc. We were unable toassess vitamin D status because we could not obtainblood samples from the children.

3

Cups Equivalent

3rd, 4th, and 5th grades at a school in Corvallis, Oregon.
Three times a week, students participating in the program
walked or ran on an outdoor track during the 20-minutemorning recess; ate a fresh fruit for morning snack
instead of the usual crackers, chips, or cookies; and ate
fruits and/or vegetables with lunch. Students were alsooffered a daily children’s multivitamin/mineral with 1000
IU of vitamin D. Lastly, we provided three modules ofnutrition education classes during the school year.

2.5

2.5
2

1.97

2.02
1.5

1.5

0.98

1

0.96

0.5
0
Fruit/Fruit Juice

Girls

Boys

Vegetables(including legumes)

Recommended Intake by USDA

Fruit and vegetable intake

continued on page 10

Continued from page 9 — LPI Fitness & Nutrition Study

Conclusions

Moderate and Vigorous Physical Activity

Our study was successful in recruiting more than 50%
of eligible students, especially females, and kept a remarkable
75% of enrolled students motivated throughout theentire school year to improve their eating and physicalactivity habits.

The Physical Activity Survey showed that the mean daily
physical activity time in all three grades was 60 minutes ormore (see figure below) and did not change significantly
throughout the study, although the participation in walking/running declined, as mentioned above. These data indicate that the children met the recommended guidelines of 60
minutes of moderate to vigorous physical activity daily but
may also suggest that the students didn’t report their levelof activity accurately.
90

Minutes per Day

80
70
60

Moderate
Activity

50
40

Vigorous
Activity

30
20
10
0

Grade 3

Grade 4

Grade 5

Number of minutes engaged daily in moderate
or vigorous activity

The high level of participation, the decrease in BMI, andthe low drop-out rates in the three 3rd grade classrooms
and one 5th grade classroom suggest that teacher support
is a critical influence on the students’ health behaviors, a
concept that needs to be further analyzed and confirmed.
It is also likely that parent support and peer pressure
influence children’s health behaviors.
The study also indicated that children are more likely to
eat fruits and vegetables when given the opportunity andencouragement. In contrast, study participation in physicalactivity was low among 4th and 5th graders and declined
over time in all grades, suggesting that it needs to be moreencouraged and incentivized, especially given the key roleof physical activity in maintaining a healthy weight.
The LPI Fitness & Nutrition Study was supported by
grants from the Spirit Mountain Community Fund and theJuan Young Trust, both in Oregon, and a generous giftfrom an anonymous donor. The children’s multivitamin/mineral supplement was a gift from USANA Health
Sciences Inc., Salt Lake City, UT. LPI

Annual Conference of the Oxygen Club of California
Stephen Lawson, LPI Administrative OfficerT

he Oxygen Club of California held its biennial scientificconference—co-sponsored by LPI—in Santa Barbara,
California, in mid-March. Oxidants and Antioxidants
in Biology: Translational Redox Science featured 44
presentations in six sessions: Wound Healing; Redox
Signaling and Inflammation; Cardiovascular; Translational
Science by Micronutrients, which included subsessions on
Carotenoids and Vitamin A, Coenzyme Q, and Polyphenols;
Redox Imaging; and Aging. There was also a poster session
with over 100 presentations covering an extraordinary
range of topics.

The keynote lectures were given by two of the 2008
Nobel Laureates in Physiology or Medicine, Harald zur
Hausen and Luc Montagnier. Zur Hausen won “for his
discovery of human papilloma viruses causing cervicalcancer” and Montagnier won, together with Françoise
Barré-Sinoussi, “for their discovery of human immunodeficiency virus.” In his presentation on “Novel infectious
agents in human carcinogenesis: State and perspectives,”
zur Hausen discussed the potential effect of vaccinations on
preventing cancers caused by hepatitis B virus and humanpapillomaviruses. He addressed the mechanism by which
certain viruses can cause the transformation of normal cells
to malignant cells, as well as the combined effects of viral

10

Fall/Winter 2010

infections, dietary factors, and other influences in thatprocess. Montagnier talked about “New horizons in
HIV/AIDS,” including his development of novel technology
to detect persistent reservoirs of HIV DNA in the blood ofpatients undergoing combined antiretroviral drug therapy.
Tissue injury triggers a number of responses that aid
in healing. Speakers in the first session addressed thismultifactorial response, which includes recruitment of
repair signals and cells to the injury site stimulated byeither hypoxia (reduced oxygen tension) in bone marrowor hyperbaric oxygen treatment, which also stimulates
angiogenesis (new blood vessel formation) at the wound.
Speakers in the second session focused on redox(reduction “electron gain”—oxidation “electron loss”)
signaling and regulation, which play important roles incellular metabolism, immune function, response to injury,
inflammation, and cell growth. The balance between
oxidants and endogenous antioxidants like thioredoxin,glutaredoxin, and peroxiredoxins controls, among otherthings, the fate of cells. In rats, resveratrol was shown to
improve cardiac parameters, including stem cell performance,
after coronary artery occlusion. In old rats, R-alpha lipoic
acid improved antioxidant capacity in the liver not by acting
itself as an antioxidant but rather by reversing age-relateddeclines in the endogenous antioxidant glutathione. Redox
imaging was discussed in the fifth session, with presentations
on new instrumentation and molecular probes that provide
imaging and measurements of reactive oxygen species in vivo.
In the third session on cardiovascular diseases, speakers
explained how redox status affects diabetes-related impairmentof angiogenesis after myocardial infarction in rats. Treatment
with a virus containing the gene for the antioxidant thioredoxin
improved outcomes. Thioredoxin also exhibits cardioprotective
effects related to the growth and death of heart muscle cells.
Oxysterols, the oxidized metabolites of cholesterol found infood and produced in the body, are associated with thedevelopment of atherosclerosis and could, because of theirinflammatory potential, contribute to other diseases.
The Norman I. Krinsky Memorial Lecture focused on
the metabolism of carotenoids. Norman Krinsky, who madeseminal contributions to carotenoid research during a longand productive career at Tufts University, died in 2008.
Carotenoids are colored compounds, some of which produce
vitamin A and play important roles in eye health andimmunity. Several speakers discussed genetic polymorphisms(variations) that probably account for the great variability
among humans in carotenoid absorption and conversion.
Indeed, intake of beta-carotene, which is converted into
vitamin A, does not always predict vitamin A status.
Vitamin A may also have an important effect on energy
production in the mitochondria.
Coenzyme Q, which also plays an important role in
the production of chemical energy in the mitochondria,
may affect apoptosis (programmed cell death) and aging.
Coenzyme Q reduces the age-related expression of oxidase
enzymes that generate superoxide radicals, which aredamaging reactive oxygen species. Treatment of astrocytes(glial cells in the central nervous system) in culture or humansubjects with statins—drugs administered to lower cholesterollevels—substantially decreased coenzyme Q levels.
Inflammatory pathways that figure in chronic diseases
may be modulated by certain dietary factors, including
resveratrol and curcumin from the spice turmeric, as well
as a host of other spices. In mice, resveratrol also shares
similarities with caloric restriction in retarding aging(represented by gene analysis), especially in the heart.
Polyphenols from plants affect redox pathways,
thereby increasing antioxidant and detoxification capacity.
However, polyphenols like ellagitannins from pomegranateshave very limited bioavailability—only very small amounts
are absorbed into the blood stream from the gut—and areextensively and rapidly chemically modified after absorption.
Therefore, it is difficult to extrapolate from cell culture
studies to in vivo behavior and from parent compounds
to their metabolic derivatives.
The last session focused on aging. Researchers showedthat specially bred mice lacking the RasGrf1 gene involvedin cognitive function and glucose homeostasis had an increased
lifespan that mimicked the effect on lifespan by caloric
restriction. Another speaker discussed the need for oxidized
protein to be degraded and removed from cells; otherwise,
protein aggregates can form that result in cellular senescence.

Age-related dysfunction in vascular cells (the endothelium)caused by oxidative stress and inflammation is similar toendothelial changes observed in young people with diabetes
or hypertension. The “triage theory” was advanced byBruce Ames to explain how micronutrient deficiencies
throughout evolution result in metabolic rebalancing tofavor those substances required for short-term survival
while starving those needed for long-term health. Chronic
micronutrient deficiencies, which are prevalent even inapparently well-nourished societies, may contribute to theincidence of age-related disease.
Bharat Aggarwal of the M. D. Anderson Cancer Centerof the University of Texas won the $25,000 Oxygen Clubof California Jarrow Formulas Health Sciences Prize for his
long-term work on the role of natural products, especially
spices, in attenuating chronic inflammation associated withthe development of cancer.
Based on their poster presentations, Jennifer Ehrenof The Salk Institute for Biological Sciences and Ryan
Hamilton of the University of Southern California won
LPI Young Investigator Awards. Dr. Ehren showed thatfisetin, a flavonoid in strawberries and other fruits,
improved multiple physiological parameters, including
nerve and kidney function, when fed to diabetic mice.
Dr. Hamilton discussed findings showing that caloric
restriction when young may help prevent hypometabolism
and mitochondrial dysfunction associated with Alzheimer’s
disease when older. LPI

FACULTY HONORS
LPI’s Maret Traber was elected
President of the Oxygen Club of
California (OCC) for 2010-2012,
succeeding Chandan Sen of Ohio
State University. LPI and OCC
co-sponsor scientific meetings and have enjoyed a longand productive association because of a shared interestin the roles of reactive oxygen species and antioxidants
in health and disease.
LPI Director Balz Frei gavethe 2010 Denham Harman,
M.D., Ph.D., Lecture in
Biomedical Gerontology at
the University of Nebraska
Medical Center in Omaha,
Nebraska, on April 9, 2010.
Dr. Harman proposed
the seminal and highly
influential “free radical
Balz Frei (left) and Denham Harman (right)
theory of aging” in 1956,
followed in 1972 by the hypothesis that mitochondria
in cells may act as a biological clock by producing free
radicals that damage organelles and biomolecules,
leading to senescence. Dr. Frei’s lecture was entitled“Oxidative Stress and Inflammation in Aging andAtherosclerosis: Ameliorating Effects of Lipoic Acid.”

The Linus Pauling Institute11

Nutrition and
Immunity, Part 2
Victoria J. Drake, Ph.D.
LPI Research AssociateManager, Micronutrient Information Center

Summary: Deficiencies of zinc, selenium, iron, and copper
adversely affect immune response. Conversely, too muchiron and copper impair immune function. Probiotics—
microorganisms often added to dairy products like yogurt—
improve immune function in the gastrointestinal system andmay help prevent inflammatory bowel disease. Obesity
produces chronic inflammation and compromised immunitythat may increase the susceptibility to inflections. Moderate,
regular exercise may enhance immunity, but prolonged
high-intensity exercise may impair it.

P

art 1 of this article (LPI Research Newsletter Spring/
Summer 2010) discussed the differences between the
innate and adaptive immune systems and focused on therole of macronutrients (protein and lipids) and vitamins.
In part 2, I discuss the role of minerals and other dietaryand lifestyle factors in immunity.

Several nutritionally-essential minerals, including zinc,selenium, iron, and copper, play important roles in thedevelopment and expression of immune responses. Zinc isrequired for both innate and adaptive immunity because it
has various catalytic, structural, and regulatory functions in
the body. Inadequate intake of zinc can lead to a nutritional
deficiency of the mineral and compromised immune function.
For instance, zinc deficiency impairs the complement system,a biochemical network of more than 30 proteins in plasmaand on cell surfaces that functions to kill invading pathogens
by direct lysis (cell rupture) or through the promotion ofphagocytosis. Phagocytosis is a process by which certain
immune cells, such as macrophages, engulf and digest
invading microorganisms and foreign particles. Zinc
deficiency also impairs other components of innate immunity,
including natural killer cell activity and the ability of immune
cells to generate oxidants that kill invading pathogens, aswell as production and function of lymphocytes—cells thatare key to mounting an adaptive response. Adaptive immune
responses, which are more complex than innate responses,
provide antigen specificity and immunologic “memory” ofpathogens; the latter makes subsequent responses to the same
pathogen more efficient. For example, vaccines function by
this process so that subsequent exposure to the pathogen
elicits a fast and efficient immune response. Zinc deficiency
results in a heightened vulnerability to several infectious
agents. In particular, children with zinc deficiency haveincreased susceptibility of infectious diarrhea, and zinc
supplementation reduces the frequency, severity, and durationof diarrheal episodes in young children. Zinc supplementationin children may also reduce the incidence of lower respiratory
infections like pneumonia. However, because of conflicting
studies, it is presently not clear whether zinc supplementation
has utility in treating childhood malaria.

12

Fall/Winter 2010

Selenium is required for normal function of several
enzymes important in innate and adaptive immunity,
including the glutathione peroxidases—key redox regulatorsand cellular antioxidants. Inadequate intake of selenium
can impair multiple immune responses, such as cytokine(cell-signaling molecules) expression, antibody production,
and aspects of cell-mediated immunity. Selenium deficiency
has been shown to enhance the virulence or progression ofsome viral infections. For example, mouse studies haveshown that a relatively harmless strain of coxsackievirus
becomes more virulent in selenium-deficient mice, resulting
in an inflammation of the heart muscle called myocarditis.
In humans, concomitant selenium deficiency andcoxsackievirus infection may both contribute to thecardiomyopathy in Keshan disease. Additionally, small
controlled trials in individuals who were not overtly selenium
deficient have found that short-term supplementation
with selenium enhances immune cell response to foreign
antigens. Other studies have established selenium to be
an important regulator of cytokine expression.
Iron is required by the host to mount an effective
immune response because the mineral is needed in the
differentiation and proliferation of T lymphocytes and in thegeneration of reactive oxygen species that kill pathogens.
Accordingly, iron deficiency—the most prevalent micronutrient deficiency in the world—results in impaired
immunity and increased morbidity and mortality from
infections. However, iron is required by most infectious
agents for replication and survival, and during the earlystages of an infection, serum levels of iron decrease andferritin (a protein that stores iron) levels increase in order
to sequester iron from pathogens. Moreover, elevated ironlevels, such as in untreated hereditary hemochromatosis(a genetic condition of iron overload despite normal ironintake), can impair phagocytic function, cytokine production,complement system activation, as well as the function of B
and T lymphocytes. Further, elevated iron levels may be arisk factor for cancer and death, especially in men. Since
iron is very efficiently recycled in the body and lost onlyin blood and skin sloughing, the Linus Pauling Instituterecommends that men and postmenopausal women who
are not at risk of iron deficiency take a multivitaminmineral supplement that does not contain iron.
Copper is also important in immunity, but the exact
mechanism of its immune action is not yet known.
Nutritional deficiency of copper results in an abnormally
low number of neutrophils, a condition called neutropenia.
Menkes disease is a genetic disorder of intracellular coppertransport. Individuals with Menkes disease suffer fromsevere copper deficiency and frequent, serious infections.
It is currently unknown if marginal or mild copper
deficiency results in impaired immunity, but high intakesof copper for prolonged periods have been shown toadversely affect immune function.
Dietary factors other than nutrients may affect immunity,
as well. For instance, yogurt and other fermented foods
may contain probiotics, which are live microorganismsthat benefit the overall health of the host when they areadministered in sufficient amounts. Bacteria of theweight, and energy homeostasis. Results of animal and invitro studies indicate that leptin also modulates inflammatory
and other immune responses, such as stimulation of proinflammatory cytokine production. Immune modulationthat occurs in obesity could increase the susceptibility ofobese individuals to infections. Some epidemiological studies
have shown that obese patients have a higher incidence of
postoperative and other hospital-related infections comparedwith patients of normal weight. Obese individuals have also
been shown to exhibit poor wound healing and increased
occurrence of skin infections.

Lactobacilli and Bifidobacteria species are common
examples. These and other probiotics can transiently
inhabit the lower gastrointestinal tract and modulate
immune function by interacting with intestinal epithelial
cells and immune cells. Studies have shown that probiotics
can benefit both innate and adaptive immunity; however,immune modulation requires regular consumption ofprobiotics since they have not been shown to permanently
alter intestinal microflora. Specific immune effects include
strengthening the intestinal epithelial barrier and stimulatingproduction of antibodies and T lymphocytes—important
mediators of the adaptive immune response. Immune effects
of probiotics may depend on the particular strain, as well as
the dose, route, and frequency of delivery. While probiotics
may have utility in the prevention of various diseases, suchas inflammatory bowel disease, diarrheal diseases, allergic
diseases, and gastrointestinal infections, more clinicalstudies are currently needed to elucidate their health effects.
While certain nutritional deficiencies, like some of themineral deficiencies mentioned above, can compromise
immunity, oversupply of nutrients may also be associatedwith untoward immune effects. Overnutrition is a form ofmalnutrition where nutrients, especially macronutrients,
are supplied in excess of the body’s needs. Overnutrition
can create an imbalance between energy intake and energy
expenditure, leading to excessive energy storage and obesity.
Obesity is a major public health problem in the UnitedStates and elsewhere because the condition is associatedwith increased risk of morbidity from a number of chronic
diseases, including hypertension and other cardiovasculardiseases, type 2 diabetes, liver and gallbladder disease,osteoarthritis, sleep apnea, and various cancers. Moreover,
obesity is linked to an increased risk of overall mortality.
Obesity has been shown to alter immunocompetence.
In obesity, immune cells called macrophages infiltrateadipose (fat) tissue and accumulate in numbers proportional
to the degree of obesity. Macrophages and other immune
cells play important roles in the development of inflammation.
Inflammatory processes are triggered in part by molecules
secreted by adipose tissue. A chronic state of low-grade
inflammation exists in obesity. Adipose tissue secretes anumber of fatty acids, cytokines, and hormones that are
involved in inflammatory and immune processes. The
hormone leptin is secreted from adipose tissue andcirculates in direct proportion to the degree of fat stores.
Leptin is an important regulator of food intake, body

An increased vulnerability, severity, or complications ofcertain infections in obesity may be related to a number offactors, such as select micronutrient deficiencies. In fact,
deficiencies or inadequacies of the B vitamins and vitamins
A, C, D, and E have been associated with obesity, probably
because energy-dense but micronutrient-poor foods are
consumed. Certain mineral deficiencies may also be linked
to obesity. For example, one study in obese children andadolescents associated impairments in cell-mediatedimmunity with deficiencies in zinc and iron. Overall, immune
responses appear to be compromised in obesity, but more
research is needed to clarify the relationship between
obesity and infection-related morbidity and mortality.
In addition to dietary factors, lifestyle choices may playa role in immunity. Moderate, regular physical activity
decreases biomarkers of systemic inflammation and may
also enhance immune function, especially in sedentaryindividuals. In contrast, high-intensity exercise for prolonged
periods (>90 minutes) increases levels of C-reactive
protein—a biomarker of cardiovascular and systemic
inflammation—and may temporarily compromise responsesof both innate and adaptive immunity. However, the effects
of exercise on immune responses are probably influenced
by a number of variables, including a person’s age, genetics,
overall health and nutritional status, as well as the type,
intensity, and duration of exercise. More clinical researchis needed to determine whether exercise-induced changes
in immune functions translate to altered risk of various
infections, such as the common cold and other respiratory
tract infections.
For more detailed information on nutrition andimmunity, see the article in the Micronutrient Information
Center: http://lpi.oregonstate.edu/infocenter/immunity.html.
This article was underwritten, in part, by a grant fromBayer Consumer Care AG, Basel, Switzerland. LPI

Kudos for the LPI Web site
“Thank you for making objective, scientifically-rooted
nutritional information available on your website. Since theinternet is littered with unsubstantiated, bizarre, andsometimes dangerous nutritional claims and advice, asite that offers well-organized, clearly stated empiricalinformation is invaluable. You are without peer inthis regard, so I always turn to your site first when
I need information. Please keep up the good work!”— Dr. Jim Conner, September 2010

The Linus Pauling Institute13

Linus Pauling Institute

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email: lpi@oregonstate.edu
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The Linus Pauling
Science Center
under construction
To see the progress on
our building, please
visit our real-time Web
cam at http://webcam.
oregonstate.edu/lpsc.
LPSC is scheduled forcompletion in summer
2011.

Look for these informative articles inside!
Page 1 ..... From the Director
Page 1 .....A New Twist on Vitamin C and Beer!

Micronutrient
Research for
Optimum HealthPage 6 .... Induction of Apoptosis in Cancer Cells
Page 7 ..... Developments
Page 8 .... The LPI Fitness & Nutrition
Study in Children

Printed on recyclable paperusing soy inks

Page 10 ..... Annual Conference of the
Oxygen Club of California

Page 12 .... Nutrition and Immunity, Part 2
Special thanks to Barbara McVicar for editorialassistance and photographs, authors of signed
articles, and Dick Willoughby for the logo
photograph of Linus Pauling.