OREGON STATE UNIVERSITY

scientific research and advances

Want to better comply with dietary guidelines, and save money? Cook dinner at home

CORVALLIS, Ore. – The best culinary paths to better health are not always paved with cash, new research shows, and cooking at home can provide the best bang-for-the-buck nutritionally as well as  financially.

A study by Arpita Tiwari, a health systems researcher at Oregon State University, and collaborators at the University of Washington confirms what many mothers and grandmothers have said for decades: that habitually eating dinner at home means a better diet and lower food expenditures compared with regularly dining out.

“Traditionally better socioeconomic status – more money – means healthier people,” said Tiwari, a graduate student at OSU's College of Public Health and Human Sciences. “That’s the trend. This research goes against that; it shows a resilience to that trend. It’s not spending more but how you spend that’s important. What you eat is important.”

“Cooking at home reduces that expenditure, and our research empirically quantifies that when we regularly eat dinner at home, our nutrition intake is better.”

Tiwari is quick to point out, though, that researchers understand the barriers to home-cooked meals.

“A mother who has two jobs and four children, even if she knows the value of home-cooked dinners, doesn’t have time to cook,” Tiwari said. “Government policy needs to be mindful of things like that when states create programs to help Medicaid populations achieve nutritional goals. Right now our system really does not allow for it. What can the government do about that? That’s what needs to be explored in the near future.”

The research involved more than 400 Seattle-area adults who were surveyed regarding a week’s worth of cooking and eating behaviors. Participants also provided various types of sociodemographic information, and their weekly food intake was graded using the Healthy Eating Index (HEI).

HEI scores range from 0 to 100, with higher scores indicating better diet quality. An index score over 81 indicates a “good” diet; 51 to 80 means “needs improvement”; and 50 or less is “poor.”

Households that cooked at home three times per week showed an average score of about 67 on the Healthy Eating Index; cooking at home six times per week resulted in an average score of around 74.

“Higher HEI scores are generally associated with higher socioeconomic status, education and income,” Tiwari said. “By contrast, cooking dinner at home depends more on the number of children at home. The study showed no association between income or education and eating at home or eating out.”

The findings also suggested that regularly eating home-cooked dinners, associated with diets lower in calories, sugar and fat, meant meeting more of the guidelines for a healthy diet as determined by the Department of Agriculture.

Eighty percent of U.S. residents fail to meet at least some of the federal dietary guidelines, the study notes, and about half the money spent on eating in the U.S. is on food not cooked at home. From the 1970s to the late 1990s, the percentage of home-cooked calories consumed fell from 82 to 68.

“HMOs should have ancillary programs to really encourage people to eat healthier,” Tiwari said. “It’s a benefit for insurance companies to get involved; eating is really the source of most of the issues that the insurance system has to deal with down the road.”

The National Institutes of Health supported this research. Findings were published in the American Journal of Preventive Medicine.

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Steve Lundeberg, 541-737-4039

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home cooking

Meal preparation

Engagement with natural environment a significant contributor to life satisfaction

CORVALLIS, Ore. – Looking to improve your overall life satisfaction? Try regularly hiking in a forest or otherwise engaging with the natural environment.

And then, for good measure, look for ways to build your trust in the scientists and policymakers involved in managing the forest where you like to hike.

New research at Oregon State University empirically demonstrates that a variety of mechanisms for engaging nature significantly contribute to a person’s overall well-being.

Chief among those, the study found, was whether people believed their surrounding environments were being managed well – for the earning of income and the underpinning of cultural practices as well as for the pursuit of recreation.

“Whether people feel like things are fair and they have a voice in process of making decisions and whether governance is transparent – those are the foundations of why people even can interact with nature,” said lead author Kelly Biedenweg of OSU’s College of Agricultural Sciences.

Biedenweg, an assistant professor in the Department of Fisheries and Wildlife, and collaborators from Colorado State University and the University of Georgia analyzed results from more than 4,400 respondents to an online survey conducted in the Puget Sound region of Washington state.

The researchers used 13 different metrics to illustrate the relationship between overall life satisfaction and engaging with the natural environment. Among those metrics were community activities, access to wild resources, stress eased by time outdoors, and trust in policymakers.

“Eleven of the 13 had a positive correlation to overall life satisfaction,” said Biedenweg, a social scientist who studies both how humans benefit from the natural environment and the impact human actions have on it. “The links between ecological conditions, like drinking water and air quality, and objective well-being have been studied quite a bit, but the connection between various aspects of engaging the natural environment and overall subjective well-being have rarely been looked at.”

“We wanted to identify the relative importance of diverse, nature-oriented experiences on a person’s overall life satisfaction assessment and statistically prove the relationship between happiness/life satisfaction and engaging with nature in many different ways.”

The researchers quantified the relationship between well-being and six common mechanisms by which nature has effects on well-being: social and cultural events; trust in governance; access to local wild resources; sense of place; outdoor recreation; and psychological benefits from time outdoors.

“Controlling for demographics, all were significantly related to life satisfaction,” Biedenweg said. “The fact that trust in governance was a significant predictor of life satisfaction – in fact, the most statistically significant predictor of the ones we looked at – it was nice to see that come out of the research. The way we manage is the gateway to people being able to get livelihoods and satisfaction from nature.”

Findings were recently published in the Journal of Environmental Psychology. The National Science Foundation and the Environmental Protection Agency supported this research.

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Steve Lundeberg, 541-737-4039

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Surf fisherman

New video shows how blue whales employ strategy before feeding

NEWPORT, Ore. – Blue whales didn’t become the largest animals ever to live on Earth by being dainty eaters and new video captured by scientists at Oregon State University shows just how they pick and choose their meals.

There is a reason for their discretion, researchers say. The whales are so massive – sometimes growing to the length of three school buses – that they must carefully balance the energy gained through their food intake with the energetic costs of feeding.

“Modeling studies of blue whales ‘lunge-feeding’ theorize that they will not put energy into feeding on low-reward prey patches,” said Leigh Torres, a principal investigator with the Marine Mammal Institute at Oregon State, who led the expedition studying the blue whales. “Our footage shows this theory in action. We can see the whale making choices, which is really extraordinary because aerial observations of blue whales feeding on krill are rare.”

“The whale bypasses certain krill patches – presumably because the nutritional payoff isn’t sufficient – and targets other krill patches that are more lucrative. We think this is because blue whales are so big, and stopping to lunge-feed and then speeding up again is so energy-intensive, that they try to maximize their effort.”

The video, captured in the Southern Ocean off New Zealand, shows a blue whale cruising toward a large mass of krill – roughly the size of the whale itself. The animal then turns on its side, orients toward the beginning of the krill swarm, and proceeds along its axis through the entire patch, devouring nearly the entire krill mass.

In another vignette, the same whale approaches a smaller mass of krill, which lies more perpendicular to its approach, and blasts through it without feeding.

“We had theorized that blue whales make choices like this and the video makes it clear that they do use such a strategy,” explained Torres, who works out of Oregon State’s Hatfield Marine Science Center in Newport, Oregon. “It certainly appears that the whale determined that amount of krill to be gained, and the effort it would take to consume the meal wasn’t worth the effort of slowing down.

“It would be like me driving a car and braking every 100 yards, then accelerating again. Whales need to be choosy about when to apply the brakes to feed on a patch of krill.”

The researchers analyzed the whale’s lunge-feeding and found that it approached the krill patch at about 6.7 miles per hour. The act of opening its enormous mouth to feed slowed the whale down to 1.1 mph – and getting that big body back up to cruising speed again requires a lot of energy.

The rare footage was possible through the use of small drones. The OSU team is trained to fly them over whales and was able to view blue whales from a unique perspective.

“It’s hard to get good footage from a ship,” Torres said, “and planes or helicopters can be invasive because of their noise. The drone allows us to get new angles on the whales without bothering them.”

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Leigh Torres, 541-867-0895, leigh.torres@oregonstate.edu

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Photo at left: Blue whale feeding on a krill patch.

 

Launching Drone
Launching of the drone.

Study examines impact of common risk factors on outcomes for home and birth center births

CORVALLIS, Ore. – Women with some characteristics commonly thought to increase pregnancy risks – being over age 35; being overweight; and in some cases, having a vaginal birth after a cesarean section – tend to have good outcomes when they give birth at home or in a birth center, a new assessment has found.

However, women with some other risk factors, a breech baby and some other cases of vaginal birth after cesarean or VBAC, may face an increased risk of poor outcomes for themselves or their babies, researchers at Oregon State University have found. The study is believed to be the first to examine these risks and the outcomes.

About 2 percent of all births in the U.S., and about 4 percent in Oregon, occur at home or in a birth center, rather than in a hospital setting. Generally, women who are considered “low-risk” are good candidates for home or birth center births, also referred to as community births, if they are attended by a midwife or other trained provider and timely access to a hospital is available.  

However, there is little agreement among health providers on what should be considered low- or high-risk, and some women choose to have a community birth despite potential risks, said Marit Bovbjerg, a clinical assistant professor of epidemiology at Oregon State University and lead author of the study.

Medical ethics and the tenets of maternal autonomy dictate that women be allowed to decide where and how they wish to give birth. That’s why it’s important to have as much information as possible about potential risks, said Bovbjerg, who works in the College of Public Health and Human Sciences at OSU.

There are also risks associated with hospital births, such as increased interventions, which means there aren’t always clear answers when it comes to determining the best and safest place to give birth, said Melissa Cheyney, a medical anthropologist and associate professor in OSU’s College of Liberal Arts.

The goal of the research was to better understand the outcomes for women and babies with some of the most common pregnancy risk factors, to see how those risk factors affected outcomes.

“There’s a middle or gray area, in terms of risk, where the risk associated with community birth is only slightly elevated relative to a completely low-risk sample,” Cheyney said. “We’re trying to get more information about births that fall in that middle zone so that clinicians and pregnant women can have the best evidence available when deciding where to give birth.”

The findings were published recently in the journal Birth. Other co-authors are Jennifer Brown of University of California, Davis; and Kim J. Cox and Lawrence Leeman of the University of New Mexico.

Using birth outcome data collected by the Midwives Alliance of North America Statistics Project, commonly referred to as MANA Stats, the researchers analyzed more than 47,000 midwife-attended community births.

They looked specifically at the independent contributions to birth outcomes of 10 common risk factors: primiparity, or giving birth for the first time; advanced maternal age, or mother over age 35; obesity; gestational diabetes; preeclampsia; post-term pregnancy, or more than 42 weeks gestation; twins; breech presentation; history of both cesarean and vaginal birth; and history of only cesarean birth.

The last two groups are both considered VBACs and hospital policies and state regulations for midwifery practice usually make no distinction between the two types. However, the researchers found a clear distinction between the two groups in terms of community birth outcomes.

Women who delivered vaginally after a previous cesarean and also had a history of previous vaginal birth had better outcomes even than those women giving birth for the first time. On the other hand, women who had never given birth to a child vaginally had an increased risk of poor outcomes in community birth settings.

“That finding suggests that current policies that universally discourage VBAC should be revisited, as the evidence does not support them,” Bovbjerg said. “Women who in the past have successfully delivered vaginally seem to do just fine the next time around, even if they have also had a previous C-section. That’s really important because some medical groups totally oppose VBACs, even in hospital settings, and many hospitals don’t offer the option of a VBAC at all.”

Researchers also found that women whose babies were in breech position had the highest rate of adverse outcome when giving birth at home or in a birth center.

There was only a slight increase in poor outcomes for women over age 35, or women who were overweight or obese, compared to those without those risk factors. In some categories, there were not enough births in the data set to properly evaluate a risk’s impact, such as with gestational diabetes and preeclampsia.

“As is appropriate, women who face high complication risks such as preeclampsia tend to plan for and choose a hospital birth, rather than a community birth,” Bovbjerg said. “But even for these women, it’s important to remember that they can choose a community birth if their faith, culture or other considerations dictate that is the best choice for them.”

The researchers emphasized that the new information about risks and outcomes can serve as an important tool in decision-making for families making very personal choices about where to give birth.

“These findings help us to put information and evidence, rather than fear, at the center of discussions around informed, shared decision-making between expectant families and their health care providers,” Cheyney said.

Researchers next plan to examine how the healthcare culture and standards of care in different locations within the U.S. affect outcomes of home and birthing center deliveries.

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Melissa Cheyney, 541-737-4515, melissa.cheyney@oregonstate.edu; Marit Bovbjerg, 541-737-5313, Marit.Bovbjerg@oregonstate.edu

Adolescents with frequent PE more fit, more informed about physical activity’s role in health

CORVALLIS, Ore. – Frequent, long-term instruction in physical education not only helps adolescents be more fit but also equips them with knowledge about how regular physical activity relates to good health, research at Oregon State University shows. 

The findings are important for several reasons. One is that regular physical education, which is on the decline nationwide, strongly correlated with students meeting the federal recommendation of at least 60 minutes per day of moderate to vigorous physical activity.

The results also showed more than one adolescent in five reported no physical education at all; nearly 40 percent of the students in the 459-person sample, whose ages ranged from 12 to 15, were obese or overweight; and only 26.8 percent met the federal government’s physical activity guidelines.

“Perhaps some were not meeting the guidelines because fewer than 35 percent actually knew what the guidelines were for their age group,” said study co-author Brad Cardinal, a professor in OSU’s School of Biological and Population Health Sciences and a nationally recognized expert on the benefits of exercise.

The guidelines call for an hour or more of physical activity at least five days a week.

The findings by OSU’s College of Public Health and Human Sciences indicate that a trend of decline in physical education mandates for middle-school students is detrimental to developing the knowledge, interests and skills that serve as a foundation for a lifelong healthy lifestyle.

Physical activity also has been shown to improve cognitive function and academic performance, Cardinal said.

“We have the physical activity guidelines for a reason, and they’re based on good science,” he said. “With only slightly more than one in four adolescents meeting the guidelines, today’s youth are being shortchanged in terms of their holistic development. They are not being prepared to live the proverbial good life.”

Cardinal notes that new guidelines will be released in 2018.

“Because of a growing propensity toward inactivity in daily life, such as increased media consumption and screen time, the guidelines very well may have to be ratcheted up to compensate,” Cardinal said.

Like physical education, participation in sports also correlated with more accurate student perceptions of the amount of physical activity necessary for good health, as well as better performance on a variety of muscular fitness-related tests.

“This underscores the importance of quality physical education in schools and the added value of sports participation,” Cardinal said. “The junior high/middle school years are a vulnerable and pivotal time in which students are typically required to take at least some physical education for at least part of the year, whereas after their freshman year in high school, most students aren’t required to take any. It’s a time when experiences in physical education and sports, whether positive or negative, can make or break whether an adolescent chooses to continue a physically active lifestyle.”

Cardinal points out that in Oregon, 2017 is supposed to represent the final year in a decade-long, statute-mandated ramp-up of physical education in public schools, but the reality is something different.

Portland Public Schools, he noted, just announced a cutback to 30 minutes of physical education every other week, whereas the law calls for 225 minutes per week for middle school students and 150 for elementary school students.

“In the federal Every Student Succeeds Act, physical education is a core subject, on par with language, math and science. Its status was elevated for a reason,” Cardinal said. “If you’re physically active, you’re going to be healthier and stronger and have fewer behavioral problems, and your cognitive function is going to be better.

“Physical education trumps sports in a head-to-head comparison of the two,” he added, “and when you have physical education plus sports, that’s when you have students who are the healthiest, fittest, strongest and most active.”

Findings were published in the American Journal of Health Promotion.

OSU alumnus Paul Loprinzi, now with the University of Mississippi, is the lead author, and the other co-authors are Marita Cardinal of Western Oregon University and Charles Corbin of Arizona State University.

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Steve Lundeberg, 541-737-4039

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Brad Cardinal

Technology to improve rockfall analysis on cliffs could save money, lives

CORVALLIS, Ore. – Researchers in the Pacific Northwest have developed a new, automated technology to analyze the potential for rockfalls from cliffs onto roads and areas below, which should speed and improve this type of risk evaluation, help protect public safety and ultimately save money and lives.

Called a “rockfall activity index,” the system is based on the powerful abilities of light detection and ranging, or LIDAR technology. It should expedite and add precision to what’s now a somewhat subjective, time-consuming process to determine just how dangerous a cliff is to the people, vehicles, roads or structures below it.

This is a multi-million dollar global problem, experts say, of significant concern to transportation planners.

It’s a particular concern in the Pacific Northwest with its many mountain ranges, heavy precipitation, erosion of steep cliffs and unstable slopes, and thousands of roads that thread their way through that terrain. The evaluation system now most widely used around the world, in fact, was developed by the Oregon Department of Transportation more than 25 years ago.

The new technology should improve on that approach, according to scientists who developed it from the University of Washington, Oregon State University and the University of Alaska Fairbanks. Findings on it were just published in Engineering Geology.

“Rockfalls are a huge road maintenance issue,” said Michael Olsen, an associate professor of geomatics in the College of Engineering at Oregon State University, and co-author of the report.

“Pacific Northwest and Alaskan highways, in particular, are facing serious concerns for these hazards. A lot of our highways in mountainous regions were built in the 1950s and 60s, and the cliffs above them have been facing decades of erosion that in many places cause at least small rockfalls almost daily. At the same time traffic is getting heavier, along with increasing danger to the public and even people who monitor the problem.”

The new approach could replace the need to personally analyze small portions of a cliff at a time, looking for cracks and hazards, with analysts sometimes even rappelling down it to assess risks. LIDAR analysis can map large areas in a short period, and allow data to be analyzed by a computer.

“Transportation agencies and infrastructure providers are increasingly seeking ways to improve the reliability and safety of their systems, while at the same time reducing costs,” said Joe Wartman, associate professor of civil and environmental engineering at the University of Washington, and corresponding author of the study.

“As a low-cost, high-resolution landslide hazard assessment system, our rockfall activity index methodology makes a significant step toward improving both protection and efficiency.”

The study, based on some examples in southern Alaska, showed the new system could evaluate rockfalls in ways that very closely matched the dangers actually experienced. It produces data on the “energy release” to be expected from a given cliff, per year, that can be used to identify the cliffs and roads at highest risk and prioritize available mitigation budgets to most cost-effectively protect public safety.

“This should improve and speed assessments, reduce the risks to people doing them, and hopefully identify the most serious problems before we have a catastrophic failure,” Olsen said.

The technology is now complete and ready for use, researchers said, although they are continuing to develop its potential, possibly with the use of flying drones to expand the data that can be obtained.

Tens of millions of dollars are spent each year in the U.S. on rock slope maintenance and mitigation.

This research was supported by the Pacific Northwest Transportation Consortium, the National Science Foundation and the Alaska Department of Transportation and Public Facilities. Co-authors included Lisa Dunham, former civil and environmental engineering graduate student at the University of Washington; graduate assistant Matthew O’Banion at OSU; and Keith Cunningham, research assistant professor of remote sensing at the University of Alaska Fairbanks.

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Michael Olsen, 541-737-9327

michael.olsen@oregonstate.edu

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A crumbling cliff
LIDAR image of cliff

Social media tools can reinforce stigma and stereotypes

CORVALLIS, Ore. – Researchers at Oregon State University have developed new software to analyze social media comments, and used this tool in a recent study to better understand attitudes that can cause emotional pain, stigmatize people and reinforce stereotypes.

In particular, the scientists studied comments and sentiments expressed about Alzheimer’s disease and other forms of dementia. It found that 51 percent of tweets by private users of Twitter accounts contained stigma, when making reference to this condition and the people who deal with it.

The new system may be applicable to a range of other social science research questions, the researchers said, and already shows that many people may not adequately appreciate the power of social media to greatly transcend the type of interpersonal, face-to-face communication humans are most accustomed to.

“As a society it’s like we’re learning a new skill of text communication, and we don’t fully understand or reflect on its power to affect so many people in ways that we may not have intended,” said Nels Oscar, an OSU graduate student in the College of Engineering and lead author on the study.

“Social media is instant, in some cases can reach millions of people at once, and can even instigate behaviors. We often don’t even know who might eventually read it and how it will affect them.”

What’s clear, the study showed, is that when it comes to Alzheimer’s disease, thoughtless or demeaning comments on a broad level via social media can take an already-serious problem and make it worse.

The particular topic studied, the scientists said, is of growing importance. A global tripling of individuals with some form of dementia is projected in coming decades, from 43 million today to 131 million by 2050.

“It was shocking to me how many people stigmatized Alzheimer’s disease and reinforced stereotypes that can further alienate people with this condition,” said Karen Hooker, holder of the Jo Anne Leonard Petersen Endowed Chair in Gerontology and Family Studies, in the OSU College of Public Health and Human Sciences. “This can create what we call ‘excess disability,’ when people with a stigmatized condition perform worse just because of the negative expectations that damaging stereotypes bring.

“This type of stigma can make it less likely that people will admit they have problems or seek treatment, when often they can still live satisfying, meaningful and productive lives. Our attitudes, the things we say affect others. And social media is now amplifying our ability to reach others with thoughtless or hurtful comments.”

The researchers noted a 2012 report which concluded that negative attitudes about Alzheimer’s disease and dementia can result in shame, guilt, hopelessness, and social exclusion among stigmatized individuals, leading to delay in diagnosis, inability to cope, and decreased quality of life. It also affects friends, family and caregivers of these individuals.

A comment a person might never make in a face-to-face conversation, Oscar said, is often transmitted via social media to dozens, hundreds or ultimately thousands of people that were not really intended. Some constraints that might reduce the impact, like clearly making a joke or using sarcasm in a personal conversation, can often get lost in translation to the printed word.

“A point many people don’t understand when using social media is that their intent is often irrelevant,” Oscar said. “All people eventually see is the comment, without any other context, and have to deal with the pain it can cause.”

This research was one part of a six-year, $2.3 million project funded by the National Science Foundation to train graduate students in aging sciences and to conduct cross-disciplinary studies on issues of importance to an aging society. The paper was recently published in the Journals of Gerontology: Psychological Sciences. The software created for the project is now freely available for other scientists to use, at http://bit.ly/2p5GmDC

In the research, the software was designed to recognize and interpret the use of various keywords associated with Alzheimer’s disease, such as dementia, memory loss or senile. The system was improved by comparing results to the same comment evaluated by human researchers, and ultimately achieved an accuracy of about 90 percent in determining whether a comment was meant to be informative, a joke, a metaphor, ridicule, or fit other dimensions.

The system was then used to analyze 33,000 tweets that made some reference to Alzheimer’s disease.

People concerned about these issues, the OSU researchers suggested, might be more conscious of their own comments on social media, and also more willing to engage with others who are using language that is insensitive or potentially hurtful.

“We should also consider ways to combat stigma and negative stereotypes by tweeting about the positive experiences of persons with dementia and people in their social networks,” Hooker said.

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Karen Hooker, 541-737-4336

hookerk@oregonstate.edu

New function discovered for compound that may help slow aging

CORVALLIS, Ore. – Researchers at Oregon State University have found that a compound called rapamycin has unusual properties that may help address neurologic damage such as Alzheimer’s disease.

A study just published in Aging Cell outlines a new understanding of how this compound works.

“It’s possible this could provide a new therapeutic approach to neurologic disease,” said Viviana Perez, an assistant professor in the Department of Biochemistry and Biophysics in OSU’s College of Science, expert on the biological processes of aging and principal investigator in the Linus Pauling Institute.

Scientists have now identified two mechanisms of action of rapamycin. One was already known. The newly-discovered mechanism is what researchers say might help prevent neurologic damage and some related diseases.

“The value of rapamycin is clearly linked to the issue of cellular senescence, a stage cells reach where they get old, stop proliferating and begin to secrete damaging substances that lead to inflammation,” Perez said. “Rapamycin appears to help stop that process.”

This secretion of damaging compounds, researchers say, creates a toxic environment called senescence-associated secretory phenotype, or SASP. It’s believed this disrupts the cellular microenvironment and alters the ability of adjacent cells to function properly, compromising their tissue structure and function.

This broad process is ultimately linked to aging.

“The increase in cellular senescence associated with aging, and the inflammation associated with that, can help set the stage for a wide variety of degenerative disease, including cancer, heart disease, diabetes and neurologic disease, such as dementia or Alzheimer’s,” Perez said. “In laboratory animals when we clear out senescent cells, they live longer and have fewer diseases. And rapamycin can have similar effects.”

Prior to this research, it had only been observed that there was one mechanism of action for rapamycin in this process. Scientists believed it helped to increase the action of Nrf2, a master regulator that can “turn on” up to 200 genes responsible for cell repair, detoxification of carcinogens, protein and lipid metabolism, antioxidant protection and other factors. In the process, it helped reduce levels of SASP.

The new study concluded that rapamycin could also affect levels of SASP directly, separately from the Nrf2 pathway and in a way that would have impacts on neurons as well as other types of cells.

“Any new approach to help protect neurons from damage could be valuable,” Perez said. “Other studies, for instance, have shown that astrocyte cells that help protect neuron function and health can be damaged by SASP. This may be one of the causes of some neurologic diseases, including Alzheimer’s disease.”

Through its ability to help prevent SASP-related cellular damage through two pathways – one involving Nrf2 and the other more directly – rapamycin will continue to generate significant interest in addressing issues related to aging, Perez said.

Rapamycin is a natural compound first discovered from the soils of Easter Island in the South Pacific Ocean. It has already been intensively studied because it can mimic the valuable effects of dietary restriction, which in some animals has been proven to extend their lifespan.

Laboratory mice that have received rapamycin have demonstrated more fitness, less decline in activity with age, improved cognition and cardiovascular health, less cancer, and a longer life.

The use of rapamycin for that purpose in humans has so far been constrained by an important side effect, an increase in insulin resistance that may raise the risk of diabetes. That concern still exists, limiting the use of rapamycin to help address degenerative disease until ways can be found to address that problem.

This may be possible. Scientists are searching for rapamycin analogs that may have similar biological impacts but don’t cause that unwanted side effect.

This research was supported by the American Federation for Aging Research.

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Viviana Perez, 541-737-9551

viviana.perez@oregonstate.edu

New drug delivery system shows promise for fighting solid tumors

PORTLAND, Ore. – A new cancer-drug delivery system shows the ability to exploit the oxygen-poor areas of solid tumors that make the growths resistant to standard chemotherapy and radiation treatment.

Carcinomas that affect the breast, lung, prostate and colon are among the solid-tumor cancers, as are malignancies in the lymphatic system, known as lymphomas, and the much less common sarcomas that arise in connective tissue.

These solid masses often contain hypoxic regions, where the concentration of oxygen in the tissue is low. Hypoxic cancer cells grow slowly, and that makes them less susceptible to the drugs prescribed to kill or damage them.

Researchers at Oregon State University have found a way to turn the tables on those cells using a “prodrug” loaded into nanostructured platforms.

A prodrug is a pharmacologically inactive compound that the body metabolizes into an active drug, in this case the cancer drug vinblastine.

Provided with the prodrug vinblastine-N-oxide by research partners at Cascade Prodrug Inc. of Eugene, Ore., OSU scientists developed two different lipid-based platform formulations known as liposomes to carry the prodrug to the tumor’s hypoxic regions. There, the lack of oxygen triggers its metabolic conversion to vinblastine.

In both formulations – one with polyethylene glycol on its surface, one without – the prodrug proved both safe and much more effective against non-small cell lung cancer than when it was delivered without a liposome.

“One of the hallmarks of these solid tumors is their hypoxic regions,” said the study’s lead author, Adam Alani of the OSU College of Pharmacy. “One reason these cancers become very aggressive is the development of this hypoxia. Since the late 1990s, researchers have been trying to take advantage of the hypoxia. The tumor model we chose, lung cancer, is one of the very well established tumors and there’s a very strong hypoxia associated with that – as well as, lung cancer is one of these cancers that in its advanced stages, it’s a terminal disease, and there’s a need for new treatments.”

By itself, vinblastine-N-oxide had shown less than optimal efficacy in testing by Cascade Prodrug because of how fast the body clears it from the system – it has a half-life of less than half an hour.

“When it was tested in mice and dogs, it did not have a chance to assimilate in the cancer tissue to produce the desired pharmacological effect,” Alani said.

But the liposomes – both the “pegylated” one containing polyethylene glycol, and the non-pegylated one – increased the half-life dramatically: to 9.5 and 5.5 hours, respectively.

“The nano carriers performed much better than the prodrug itself,” Alani said. “We were able to literally cure the tumor.”

Alani’s research began with laboratory cultures and progressed to safety and efficacy testing in animals.

“We made sure the nanostructure platform worked properly against lung cancer in vitro, then looked at the safety of the formulation in healthy mice and looked at the maximum tolerated dose – the biggest dose you can use without producing side effects,” Alani said. “Then we determined how long the nano carriers could keep the drug in the blood compared to the drug without the nanostructures.”

When those data were “very encouraging,” Alani’s team assessed the efficacy of the formulations in mice that had tumors grafted into them.

Without any liposome, the drug showed some tumor suppression, but the mice that had received the drug alone had to be euthanized after 70 days because of tumors that were no longer being controlled.

Mice that had received the drug with one of the liposomes were healthy and tumor-free for the nearly 100-day run of the experiment.

“The formulations clearly performed better than the unformulated drug as well as much better than Cisplatin, the standard-of-care drug for this research,” Alani said. “Now we’re collaborating with Cascade Prodrug and the College of Veterinary Medicine to assess safety and efficacy in dog models, and trying to look at other tumors, like bladder cancer, associated with dogs.”

One goal, Alani said, is to develop a new treatment for cancer in dogs, and another is to look at dogs as a model for drug development – “to get data Cascade can use to move the process forward for approval for use in dogs, as well as preliminary data for a new drug application with the FDA,” Alani said.

The Oregon Nanoscience and Microtechnologies Institute supported this research. Findings were recently published in the Journal of Controlled Release.

Co-authors on the paper were Alani’s colleagues in the Department of Pharmaceutical Sciences, Vidhi Shah, Duc Nguyen and Adel Alfatease, and Shay Bracha of the OSU veterinary college’s Department of Clinical Sciences.

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Steve Lundeberg, 541-737-4039

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Even short-duration heat waves could lead to failure of coffee crops

CORVALLIS – “Hot coffee” is not a good thing for java enthusiasts when it refers to plants beset by the high-temperature stress that this century is likely to bring, research at Oregon State University suggests.

A study by OSU’s College of Forestry showed that when Coffea arabica plants were subjected to short-duration heat waves, they became unable to produce flowers and fruit.

That means no coffee beans, and no coffee to drink.

C. arabica is the globe’s dominant coffee-plant species, accounting for 65 percent of the commercial production of the nearly 20 billion pounds of coffee consumed globally each year.

Continually producing new flushes of leaves year-round, C. arabica grows on 80 countries in four continents in the tropics.

The OSU research investigated how leaf age and heat duration affected C. arabica’s recovery from heat stress during greenhouse testing. A major finding was that the younger, “expanding” leaves were particularly slow to recover compared to mature leaves, and that none of the plants that endured the simulated heat waves produced any flowers or fruit.

“This emphasizes how sensitive Coffea arabica is to temperature,” said lead author Danielle Marias, a plant physiologist with OSU’s Department of Forest Ecosystems and Society. “No flowering means no reproduction which means no beans, and that could be devastating for a coffee farmer facing crop failure.

“Heat is very stressful to the plants and is often associated with drought. However, in regions where coffee is grown, it may not just be hotter and drier, it could be hotter and wetter, so in this research we wanted to isolate the effects of heat.”

In the OSU study, C. arabica plants were exposed to heat that produced leaf temperatures of a little over 120 degrees Fahrenheit, for either 45 or 90 minutes. That leaf temperature, Marias emphasizes, is a realistic result of global climate change and also more than the surrounding air temperature – think of how hot, for example, asphalt gets in the sunshine on a 90-degree day.

Expanding leaves subjected to the 90-minute treatment took the longest to recover physiologically as measured by photosynthesis; chlorophyll fluorescence, an indicator of photosynthetic energy conversion; and the presence of nonstructural carbohydrates, which include starch and free sugars involved in growth, reproduction and other functions.

“In both treatments, photosynthesis of expanding leaves recovered more slowly than in mature leaves, and stomatal conductance of expanding leaves was reduced in both heat treatments,” Marias said. “Based on the leaf energy balance model, the inhibited stomatal conductance reduces evaporative cooling of leaves, which could further increase leaf temperatures, exacerbating the aftereffects of heat stress under both full and partial sunlight conditions, where C. arabica is often grown.”

Regardless of leaf age, the longer heat treatment resulted in decreased water-use efficiency, which could also worsen the effects of heat stress, particularly during drought.

Results of the research were recently published in Ecology and Evolution. The National Science Foundation supported the study, co-authors of which were Frederick Meinzer of the U.S. Forest Service and Christopher Still of the OSU Department of Forest Ecosystems and Society.

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