OREGON STATE UNIVERSITY

heath and nutrition

Drug interactions causing a significant impact on statin use

CORVALLIS, Ore. – A new study has found that many people who stopped taking cholesterol-lowering statin drugs were also taking an average of three other drugs that interfered with the normal metabolism of the statins.

The other drugs can contribute to a common side effect of taking statins - muscle pain – and often led people to discontinue use of a medication that could otherwise help save their life, researchers learned.

The interactions of many drugs with statins have been known of for some time, researchers said, but are not being adequately managed by physicians and pharmacists, who could often choose different medications or adjust dosages to retain the value of statin drugs without causing this side effect.

The research, done as part of a survey of more than 10,000 current and former statin users, found that use of medications which interfere with statin metabolism almost doubles the chance that a person will discontinue statin use due to muscle pain.

The issue is of growing importance because statin drugs are some of the most widely used medications in the world, proven to lower LDL, or “bad” cholesterol, and decrease the risk of heart attacks, heart disease, strokes and death. About 20 million people in the U.S. now take statins, and new guidelines have just been issued to further expand the types of health conditions for which statins may be of benefit. Based on those guidelines, the number of statin users could increase to more than 30 million.

The findings were published in the Journal of Clinical Lipidology by scientists from Oregon State University and four other universities or research institutes.

“We’ve known for some time of many medications that can interact with statins, but only now is it becoming clear that this is a significant contributor to the side effects, and often the reason some patients stop taking statins,” said Matt Ito, a professor in the OSU College of Pharmacy and president of the National Lipid Association, which funded this study.

“This issue is something physicians, pharmacists and patients all need to be more aware of,” Ito said. “There’s a lot we can do besides discontinue use of these valuable medications. You can change dosages, use drugs that don’t cause interactions, use different types of statins. Patients need to be proactive in understanding this issue and working with their health care providers to address it.”

Persons who have problems taking statins should discuss options with their physicians or pharmacists, Ito said, and not assume the drug has be to discontinued. A Medscape web site at http://reference.medscape.com/drug-interactionchecker also can help individuals learn more about possible interactions between statins and the full range of medications they may be taking.

Statins are usually well-tolerated, but in the recent survey, a muscle-related side effect was reported by 29 percent of participants. In former statin users, 62 percent of the people said that side effects, mostly muscle pain, were the reason they stopped taking the drugs.

There are many drugs that can interfere with statin metabolism, increase systemic exposure to the statin and raise the risk of this muscle pain, the researchers said in their report. This can include some common antibiotics, cardiovascular drugs, and others taken for treatment of cancer, mental health, HIV treatment and other conditions.

These interactions are not always adequately considered by physicians and pharmacists, however. One recent report found that as many as 20 percent of significant statin-drug interactions were missed in 64 pharmacies.

Besides drug interactions, statin side effects are also more common in women and associated with increasing age, history of cardiovascular disease, and some other conditions. Statin discontinuation has been associated with increased cardiovascular morbidity and death.

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Matt Ito, 503-494-3657

Excess omega-3 fatty acids could lead to negative health effects

CORVALLIS, Ore. – A new review suggests that omega-3 fatty acids taken in excess could have unintended health consequences in certain situations, and that dietary standards based on the best available evidence need to be established.

“What looked like a slam dunk a few years ago may not be as clear cut as we thought,” said Norman Hord, associate professor in OSU’s College of Public Health and Human Sciences and a coauthor on the paper.

“We are seeing the potential for negative effects at really high levels of omega-3 fatty acid consumption. Because we lack valid biomarkers for exposure and knowledge of who might be at risk if consuming excessive amounts, it isn’t possible to determine an upper limit at this time.”

Previous research led by Michigan State University’s Jenifer Fenton and her collaborators found that feeding mice large amounts of dietary omega-3 fatty acids led to increased risk of colitis and immune alteration. Those results were published in Cancer Research in 2010.

As a follow-up, in the current issue of the journal Prostaglandins, Leukotrienes & Essential Fatty Acids, Fenton and her co-authors, including Hord, reviewed the literature and discuss the potential adverse health outcomes that could result from excess consumption of omega-3 fatty acids.

Studies have shown that omega-3s, also known as long chain polyunsaturated fatty acids (LCPUFAs), are associated with lower risk of sudden cardiac death and other cardiovascular disease outcomes.

“We were inspired to review the literature based on our findings after recent publications showed increased risk of advanced prostate cancer and atrial fibrillation in those with high blood levels of LCPUFAs,” Fenton said.

Omega-3 fatty acids have anti-inflammatory properties, which is one of the reasons they can be beneficial to heart health and inflammatory issues. However, the researchers said excess amounts of omega-3 fatty acids can alter immune function sometimes in ways that may lead to a dysfunctional immune response to a viral or bacterial infection.

“The dysfunctional immune response to excessive omega-3 fatty acid consumption can affect the body’s ability to fight microbial pathogens, like bacteria,” Hord said.

Generally, the researchers point out that the amounts of fish oil used in most studies are typically above what one could consume from foods or usual dosage of a dietary supplement. However, an increasing amount of products, such as eggs, bread, butters, oils and orange juice, are being “fortified” with omega-3s. Hord said this fortified food, coupled with fish oil supplement use, increases the potential for consuming these high levels.

“Overall, we support the dietary recommendations from the American Heart Association to eat fish, particularly fatty fish like salmon, mackerel, lake trout or sardines, at least two times a week, and for those at risk of coronary artery disease to talk to their doctor about supplements,” he said.

“Our main concern here is the hyper-supplemented individual, who may be taking high-dose omega-3 supplements and eating four to five omega-3-enriched foods per day,” Hord added. “This could potentially get someone to an excessive amount. As our paper indicates, there may be subgroups of those who may be at risk from consuming excess amounts of these fatty acids.”

Hord said there are no evidence-based standards for omega-3 intake and no way to tell who might be at health risk if they consume too high a level of these fatty acids.

“We’re not against using fish oil supplements appropriately, but there is a potential for risk,” Hord said. “As is all true with any nutrient, taking too much can have negative effects. We need to establish clear biomarkers through clinical trials. This is necessary in order for us to know who is eating adequate amounts of these nutrients and who may be deficient or eating too much.

“Until we establish valid biomarkers of omega-3 exposure, making good evidence-based dietary recommendations across potential dietary exposure ranges will not be possible.”

Sanjoy Ghosh from University of BC-Okanagan, Canada and Eric Gurzell from Michigan State University also contributed to this study, which was supported by grants from the National Institutes of Health and the Canadian Diabetes Association.

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Norman Hord, 541-737-5923

Beyond antibiotics: “PPMOs” offer new approach to bacterial infection

CORVALLIS, Ore. – Researchers at Oregon State University and other institutions today announced the successful use of a new type of antibacterial agent called a PPMO, which appears to function as well or better than an antibiotic, but may be more precise and also solve problems with antibiotic resistance.

In animal studies, one form of PPMO showed significant control of two strains of Acinetobacter, a group of bacteria of global concern that has caused significant mortality among military personnel serving in Middle East combat.

The new PPMOs offer a fundamentally different attack on bacterial infection, researchers say.

They specifically target the underlying genes of a bacterium, whereas conventional antibiotics just disrupt its cellular function and often have broader, unwanted impacts. As they are further developed, PPMOs should offer a completely different and more precise approach to managing bacterial infection, or conceptually almost any disease that has an underlying genetic component.

The findings were published today in the Journal of Infectious Diseases, by researchers from OSU, the University of Texas Southwestern Medical Center, and Sarepta, Inc., a Corvallis, Ore., firm.

“The mechanism that PPMOs use to kill bacteria is revolutionary,” said Bruce Geller, a professor of microbiology in the OSU College of Science and lead author on the study. “They can be synthesized to target almost any gene, and in that way avoid the development of antibiotic resistance and the negative impacts sometimes associated with broad-spectrum antibiotics.

“Molecular medicine,” Geller said, “is the way of the future.”

PPMO stands for a peptide-conjugated phosphorodiamidate morpholino oligomer – a synthetic analog of DNA or RNA that has the ability to silence the expression of specific genes. Compared to conventional antibiotics, which are often found in nature, PPMOs are completely synthesized in the laboratory with a specific genetic target in mind.

In animal laboratory tests against A. baumannii, one of the most dangerous Acinetobacter strains, PPMOs were far more powerful than some conventional antibiotics like ampicillin, and comparable to the strongest antibiotics available today. They were also effective in cases where the bacteria were resistant to antibiotics.

PPMOs have not yet been tested in humans. However, their basic chemical structure, the PMO, has been extensively tested in humans and found safe. Although the addition of the peptide to the PPMO poses an uncertain risk of toxicity, the potency of PPMOs reduces the risk while greatly improving delivery of the PMOs into bacterial cells, Geller said.

Geller said research is being done with Acinetobacter in part because this pathogen has become a huge global problem, and is often spread in hospitals. It can cause respiratory infection, sepsis, and is a special concern to anyone whose immune system is compromised. Wounds in military battle conditions have led to numerous cases in veterans, and A. baumannii is now resistant to many antibiotics. “Urgent new approaches to therapeutics are needed,” the scientists said in their report.

Continued research and eventually human clinical trials will be required before the new compounds are available for health care, the researchers said. This and continued studies have been supported by the National Institutes of Health, the other collaborators and the N.L. Tartar fund.

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Editor’s Note: A scanning electron microscope image of A. baumannii is available online (please provide image credit as indicated at web site): http://bit.ly/GztejR

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Bruce Geller, 541-737-1845

Innovative approach could ultimately end deadly disease of sleeping sickness

CORVALLIS, Ore. – A tag team of two bacteria, one of them genetically modified, has a good chance to reduce or even eliminate the deadly disease African trypanosomiasis, or sleeping sickness, researchers at Oregon State University conclude in a recent mathematical modeling study.

African trypanosomiasis, caused by a parasite carried by the tsetse fly, infects 30,000 people in sub-Saharan Africa each year and is almost always fatal without treatment. In a 2008 epidemic, 48,000 people died.

In this research, scientists evaluated the potential for success of a new approach to combat the disease – creating a genetically modified version of the Sodalis bacteria commonly found in the gut of the flies that carry the disease, and using different bacteria called Wolbachia to drive the GMO version of Sodalis into fly populations.

When that’s done, the GMO version of Sodalis would kill the disease-causing trypanosome parasite. According to the analysis published in PLOS Neglected Tropical Diseases, researchers say this should work – and could offer a model system for other tropical, insect-carried diseases of even greater importance, including dengue fever and malaria.

“There are a few ‘ifs’ necessary for this to succeed, but none of them look like an obstacle that could not be overcome,” said Jan Medlock, an assistant professor in the OSU Department of Biomedical Sciences, and lead author on the new report.

“If everything goes right, and we are optimistic that it will, this could be enormously important,” Medlock said. “There’s a potential here to completely solve this disease that has killed many thousands of people, and open new approaches to dealing with even more serious diseases such as malaria.”

Some of the “ifs” include: the transgenic Sodalis has to be reasonably effective at blocking the parasite, at or above a level of about 85 percent; the Wolbachia bacteria, which has some effect on the health of flies affected with it, must not kill too many of them; and the target species of fly has to be a majority of the tsetse flies in the areas being treated.

The research shows that dealing with all of those obstacles should be possible. If so, this might spell the end of a tropical disease that has plagued humans for hundreds, possibly thousands of years. African trypanosomiasis causes serious mental and physical deterioration – including the altered sleep patterns that give the disease its name – and is fatal without treatment. It’s still difficult to treat, and neurologic damage is permanent.

Past efforts to control the disease, including insect traps, insecticide spraying, and use of sterile insects have been of some value, but only in limited areas and the effects were not permanent.

The strength of the new approach, researchers say, is that once the process begins it should spread and be self-sustaining - it should not be necessary to repeatedly take action in the huge geographic areas of Africa. Due to some genetic manipulation, the flies carrying the Wolbachia bacteria should naturally increase their populations and have an inherent survival advantage over conventional tsetse flies.

As the flies carrying transgenic bacteria continue to dominate and their populations spread, trypanosomiasis should fairly rapidly disappear. Whether the mechanism of control could wane in effectiveness over time is an issue that requires further study, scientists said.

Work has begun on the GMO version of Sodalis that has the capability to resist trypanosomes . It’s not yet finalized, Medlock said, but it should be possible, and when complete, the bacteria will be very specific to tsetse flies.

Medlock, an expert in modeling the transmission of various diseases – including human influenza – says the analysis is clear that this approach has significant promise of success. Because of the relatively low infectiousness of the parasite and the ability of Wolbachia to drive the resistance genes, no part of the system has to be 100 percent perfect in order to ultimately achieve near eradication of this disease, he said.

Accomplishing a similar goal with diseases such as malaria may be more difficult, he said, because that disease historically has shown a remarkable ability to mutate and overcome many of the approaches used to attack it. However, at least some near-term gains may be possible, he said.

Collaborators on this study included scientists from the OSU College of Veterinary Medicine and the Yale School of Public Health. It was supported by the National Institutes of Health and the Miriam Weston Trust.

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Jan Medlock, 541-737-6874

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Tsetse fly

Tsetse fly

California’s new mental health system helps people live independently

CORVALLIS, Ore. – A new analysis by Oregon State University researchers of California’s mental health system finds that comprehensive, community-based mental health programs are helping people with serious mental illness transition to independent living.

Published in the October issue of the American Journal of Public Health, this study has important implications for the way that states finance and deliver mental health programs, and speaks to the effectiveness of well-funded, comprehensive community programs.

In November of 2004, California voters passed the Mental Health Services Act, which allocated more than $3 billion for comprehensive community mental health programs, known as Full Service Partnerships (FSP). While community-based, these programs are different from usual mental health services programs in most states because they provides a more intensive level of care and a broader range of mental health services and supports, such as medication management, crisis intervention, case management and peer support.

It also provides services such as food, housing, respite care and treatment for co-occurring disorders, such as substance abuse.

“We found that these programs promoted independent living in the community among people who had serious mental illness but had not been served or underserved previously,” said Jangho Yoon, an assistant professor of health policy and health economist in OSU’s College of Public Health and Human Sciences and lead author of the study. “Overall, it reduced their chance of living on the street or being incarcerated in jails and prisons.”

The researchers looked at data from 43 of California’s 53 counties, resulting in a sample of 9,208 adults over the course of four years. They found that participants who stayed enrolled in the program continuously, without interruption, were 13.5 percent more likely to successfully transition to independent living.

However, they found that non-white patients were less likely to live independently, and more likely to end up in jail or homeless.

“Although FSPs represent the most well-funded comprehensive community-based programs in the country, they are still community programs and therefore program participation is voluntary,” Yoon said.  “My guess is that minorities may not benefit fully from these programs in their communities possibly due to greater stigma, and less family/social supports. But it needs further investigation.”

Patients with schizophrenia and bipolar disorders were also less likely to benefit from the community programs, because of the nature and severity of their mental health issues.

Yoon is an expert on health management policy, specifically policy around the area of mental health. He said other states haven’t followed California’s lead, in part because of the cost of such extensive programming. Yoon said some of the funding made possible by the federal Patient Protection and Affordable Care Act, which includes $460 million for community mental health services for states to use, may help other states to create similar programs.

“Nobody would disagree that the public mental health system has historically been under-funded in the U.S.,” he said. “The message for other states is clear: investment in well-funded, recovery-oriented, comprehensive community mental health programs clearly improves lives of people with serious mental illness, and may also save money from reduced dependency and incarcerations in this population.”

Tim Bruckner of the University of California, Irvine, and Timothy Brown of the University of California, Berkeley, contributed to this study, which was jointly funded by the California Department of Mental Health and the California Health Care Foundation.

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Jangho Yoon, 541-737-3839

Gut microbes closely linked to range of health issues

CORVALLIS, Ore. –A new understanding of the essential role of gut microbes in the immune system may hold the key to dealing with some of the more significant health problems facing people in the world today, Oregon State University researchers say in a new analysis.

Problems ranging from autoimmune disease to clinical depression and simple obesity may in fact be linked to immune dysfunction that begins with a “failure to communicate” in the human gut, the scientists say. Health care of the future may include personalized diagnosis of an individual’s “microbiome” to determine what prebiotics or probiotics are needed to provide balance.

Appropriate sanitation such as clean water and sewers are good. But some erroneous lessons in health care may need to be unlearned – leaving behind the fear of dirt, the love of antimicrobial cleansers, and the outdated notion that an antibiotic is always a good idea. We live in a world of “germs” and many of them are good for us.

“Asked about their immune system, most people might think of white blood cells, lymph glands or vaccines,” said Dr. Natalia Shulzhenko, author of a new report in Clinical Reviews in Allergy and Immunology, and assistant professor and physician in the OSU Department of Biomedical Sciences. “They would be surprised that’s not where most of the action is. Our intestines contain more immune cells than the entire rest of our body.

“The human gut plays a huge role in immune function,” Shulzhenko said. “This is little appreciated by people who think its only role is digestion. The combined number of genes in the microbiota genome is 150 times larger than the person in which they reside. They do help us digest food, but they do a lot more than that.”

An emerging theory of disease, Shulzhenko said, is a disruption in the “crosstalk” between the microbes in the human gut and other cells involved in the immune system and metabolic processes.

“In a healthy person, these microbes in the gut stimulate the immune system as needed, and it in turn talks back,” Shulzhenko said. “There’s an increasing disruption of these microbes from modern lifestyle, diet, overuse of antibiotics and other issues. With that disruption, the conversation is breaking down.”

An explosion of research in the field of genomic sequencing is for the first time allowing researchers to understand some of this conversation and appreciate its significance, Shulzhenko said. The results are surprising, with links that lead to a range of diseases, including celiac disease and inflammatory bowel disease. Obesity may be related. And some studies have found relevance to depression, late-onset autism, allergies, asthma and cancer.

In the new review, researchers analyzed how microbe dysfunction can sometimes result in malabsorption and diarrhea, which affects tens of millions of children worldwide and is often not cured merely by better nutrition. In contrast, a high-fat diet may cause the gut microbes to quickly adapt to and prefer these foods, leading to increased lipid absorption and weight gain.

The chronic inflammation linked to most of the diseases that kill people in the developed world today – heart disease, cancer, diabetes – may begin with dysfunctional gut microbiota.

Understanding these processes is a first step to addressing them, Shulzhenko said. Once researchers have a better idea of what constitutes healthy microbiota in the gut, they may be able to personalize therapies to restore that balance. It should also be possible to identify and use new types of probiotics to mitigate the impact of antibiotics, when such drugs are necessary and must be used.

Such approaches are “an exciting target for therapeutic interventions” to treat health problems in the future, the researchers concluded.

The study, supported by OSU, included researchers from both the College of Veterinary Medicine and the College of Pharmacy.

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Dr. Natalia Shulzhenko, 541-737-1051

OSU Be Well Walk & Run on Oct. 11

CORVALLIS, Ore. – Oregon State University is holding the fourth annual Be Well Walk & Run on Oct. 11 in the Memorial Union Quad. The event is free and open to everyone.

This year’s event includes a five-kilometer running course as well as a one-mile walking course (5k Map / 1-Mile Map). The scenic route will wind participants throughout OSU’s campus, highlighting picturesque buildings and spaces. Costumes are encouraged. 

The event will feature activity stations in the Memorial Union Quad to engage participants in learning about the Healthy Campus Initiative, including physical activity, stress management, nutrition and a smoke-free campus.

Participants can register as individuals or as part of a group.  Early registrants will receive a free 2013 Be Well Walk & Run t-shirt. To register, go to http://bit.ly/19Zo7Rk. The run starts at 3:30 p.m. in the quad, check in begins at 3 p.m.

For more information, go to http://oregonstate.edu/bewell

Accommodations for disabilities may be made by calling Joe Schaffer, 541-737-4884.

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Lisa Hoogesteger, 541-737-3343

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Traber honored for research on vitamin E

CORVALLIS, Ore. – Maret Traber, a professor in the College of Public Health and Human Sciences at Oregon State University, and principal investigator in the Linus Pauling Institute, has received an international honor for her work on vitamin E.

Traber received the DSM Nutritional Science Award 2013 on fundamental or applied research in human nutrition, which included an honorarium of 50,000 Euros. It recognizes her lifetime commitment to research on vitamin E and many new insights into its role in human nutrition and optimum health.

Traber is director of the Oxidative and Nitrative Stress Laboratory at OSU and is the Helen P. Rumbel Professor for Micronutrient Research. She has published nearly 250 professional publications on vitamin E, on such topics as its bioavailability, kinetics, metabolism, and effects of vitamin E deficiency – especially in people with particular health concerns, such as burn victims or diabetics.

She received the award in Granada, Spain at the IUNS 20th International Congress of Nutrition.

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Maret Traber, 541-737-7977

ACL injuries may be prevented by different landing strategy

CORVALLIS, Ore. – Women are two to eight times more likely than men to suffer a debilitating tear of the anterior cruciate ligament (ACL) in the knee and a new study suggests that a combination of body type and landing techniques may be to blame.

In two new studies published online this week in the Journal of Athletic Training, lead author Marc Norcross of Oregon State University documents how women who were asked to undergo a series of jumping exercises landed more often than men in a way associated with elevated risk of ACL injuries.

Both men and women tended to land stiffly, which can lead to ACL injuries, but women were 3.6 times more likely to land in a “knock-kneed” position, which the researchers say may be the critical factor leading to the gender disparity in ACL tears.

“We found that both men and women seem to be using their quad region the same, so that couldn’t explain why females are more at risk,” Norcross said. “Using motion analysis, we were able to pinpoint that this inability to control the frontal-plane knee loading – basically stress on the knee from landing in a knock-kneed position – as a factor more common in women.

“Future research may isolate why women tend to land this way,” he added, “but it could in part be because of basic biology. Women have wider hips, making it more likely that their knees come together after jumping.”

Norcross, an assistant professor of exercise and sport science in OSU’s College of Public Health and Human Sciences, is a former collegiate athletic trainer dedicating his research to the prevention of ACL tears.

“You see ACL injuries in any sport where you have a lot of jump stops and cuts, so basketball, soccer, lacrosse, and volleyball are high-risk sports,” said Norcross. “We know that people who hurt themselves tend to look stiff when they land and that the combined ‘knee loading’ from multiple directions is likely causing the injury event. But it wasn’t clear initially why women had more injuries than men.”

The researchers used motion analysis software to monitor the landing strategies of 82 physically active men and women. They found that both males and females had an equal likelihood of landing stiffly – likely from tensing the muscles in their quads before landing – putting them at higher risk of ACL tears. Women, however, were more likely to land in a “knee valgus” position, essentially knock-kneed.

Norcross said his next research project will focus on high school athletes, looking at a sustainable way to integrate injury prevention into team warm-up activities through improving landing technique.

“We are trying to create a prevention strategy that is sustainable and will be widely used by high school coaches,” he said. “A lot of athletes do come back from an ACL injury, but it is a long road. And the real worry is that it leads to early onset arthritis, which then impacts their ability to stay physically active.”

This study was supported by the NATA Research & Education Foundation Doctoral Grant Program.

Researchers from University of North Carolina at Chapel Hill and Greensboro contributed to this study.

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Marc Norcross, 541-737-6788

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ACL jumping landing
Biomechanical model of a female using a “knock-kneed” technique and experiencing high frontal plane knee loading during a jump landing.

Cognitive decline with age is normal, routine – but not inevitable

CORVALLIS, Ore. – If you forget where you put your car keys and you can’t seem to remember things as well as you used to, the problem may well be with the GluN2B subunits in your NMDA receptors.

And don’t be surprised if by tomorrow you can’t remember the name of those darned subunits.

They help you remember things, but you’ve been losing them almost since the day you were born, and it’s only going to get worse. An old adult may have only half as many of them as a younger person.

Research on these biochemical processes in the Linus Pauling Institute at Oregon State University is making it clear that cognitive decline with age is a natural part of life, and scientists are tracking the problem down to highly specific components of the brain. Separate from some more serious problems like dementia and Alzheimer’s disease, virtually everyone loses memory-making and cognitive abilities as they age. The process is well under way by the age of 40 and picks up speed after that.

But of considerable interest: It may not have to be that way.

“These are biological processes, and once we fully understand what is going on, we may be able to slow or prevent it,” said Kathy Magnusson, a neuroscientist in the OSU Department of Biomedical Sciences, College of Veterinary Medicine, and professor in the Linus Pauling Institute. “There may be ways to influence it with diet, health habits, continued mental activity or even drugs.”

The processes are complex. In a study just published in the Journal of Neuroscience, researchers found that one protein that stabilizes receptors in a young animal – a good thing conducive to learning and memory – can have just the opposite effect if there’s too much of it in an older animal.

But complexity aside, progress is being made. In recent research, supported by the National Institutes of Health, OSU scientists used a genetic therapy in laboratory mice, in which a virus helped carry complementary DNA into appropriate cells and restored some GluN2B subunits. Tests showed that it helped mice improve their memory and cognitive ability.

The NMDA receptor has been known of for decades, Magnusson said. It plays a role in memory and learning but isn’t active all the time – it takes a fairly strong stimulus of some type to turn it on and allow you to remember something. The routine of getting dressed in the morning is ignored and quickly lost to the fog of time, but the day you had an auto accident earns a permanent etching in your memory.

Within the NMDA receptor are various subunits, and Magnusson said that research keeps pointing back to the GluN2B subunit as one of the most important. Infants and children have lots of them, and as a result are like a sponge in soaking up memories and learning new things. But they gradually dwindle in number with age, and it also appears the ones that are left work less efficiently.

“You can still learn new things and make new memories when you are older, but it’s not as easy,” Magnusson said. “Fewer messages get through, fewer connections get made, and your brain has to work harder.”

Until more specific help is available, she said, some of the best advice for maintaining cognitive function is to keep using your brain. Break old habits, do things different ways. Get physical exercise, maintain a good diet and ensure social interaction. Such activities help keep these “subunits” active and functioning.

Gene therapy such as that already used in mice would probably be a last choice for humans, rather than a first option, Magnusson said. Dietary or drug options would be explored first.

“The one thing that does seem fairly clear is that cognitive decline is not inevitable,” she said. “It’s biological, we’re finding out why it happens, and it appears there are ways we might be able to slow or stop it, perhaps repair the NMDA receptors. If we can determine how to do that without harm, we will.”

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Kathy Magnusson, 541-737-6923