High and low exercise intensity found to influence brain function differently
Study suggests that exercise could play a role as a therapeutic strategy in neurological and psychiatric disorders
January 30, 2020
Science Daily/IOS Press
A new study shows for the first time that low and high exercise intensities differentially influence brain function. Using resting state functional magnetic resonance imaging (Rs-fMRI), a noninvasive technique that allows for studies on brain connectivity, researchers discovered that low-intensity exercise triggers brain networks involved in cognition control and attention processing, while high-intensity exercise primarily activates networks involved in affective/emotion processing. The results appear in a special issue of Brain Plasticity devoted to Exercise and Cognition.
"We believe that functional neuroimaging will have a major impact for unraveling body-brain interactions," said lead investigators Angelika Schmitt, MSc, and Henning Boecker, MD, Functional Neuroimaging Group, Department of Radiology, University Hospital Bonn, Bonn, Germany. "These novel methods allow us to 'look' directly into the brains of a group of athletes, and, maybe even more importantly, understand the dynamic changes in brain structure and function associated with the transition from a sedentary to a healthy lifestyle.
Twenty-five male athletes underwent individual assessments using an incremental treadmill test. On separate days they performed low- and high-intensity exercise bouts for 30 minutes. Before and after exercising, Rs-fMRI was used to examine functional connectivity of different brain regions that are linked to specific behavioral processes. Participants also completed a questionnaire to measure positive and negative mood before and after the exercise.
The behavioral data showed a significant increase in positive mood after both exercise intensities and no significant change in negative mood. The results of the Rs-fMRI tests showed that low-intensity exercise led to increased functional connectivity in networks associated with cognitive processing and attention. High-intensity exercise, on the other hand, led to increased functional connectivity in networks related to affective, emotional processes. High-intensity exercise also led to a decreased functional connectivity in networks associated with motor function.
The investigators note that this is the first study to report distinct effects of exercise intensity on specific functional networks within the brain at rest. Future research in this area will help provide neurobiological evidence about what type of exercise intensity is best suited for certain neurological or behavioral modulations and may pave the way for supportive clinical applications in patients or for enhancing brain functional plasticity.
https://www.sciencedaily.com/releases/2020/01/200130115430.htm
Movement study could be significant in helping understand brain rehabilitation
January 30, 2020
Science Daily/University of Plymouth
The human brain's ability to recall a single movement is significantly affected by the characteristics of previous actions it was learned with, a new study has shown.
Research led by the University of Plymouth explored how distinct prior actions affected a person's ability to perform certain simple movements, corresponding to, for example, reaching to catch a ball or drinking a cup of coffee.
It showed that prior visual and physical motions exert different influences on the effectiveness of a particular action, but that the strength of influence depends on their similarity to the condition in which it was learned.
As such, actual physical movement had a far greater influence on the success of any given action than mere observation of movement, which the authors suggest is because of the longer time taken for the brain to process a visual as opposed to a physical movement.
Scientists believe it is an important step in understanding how the brain controls motor functions, which could be particularly important for those working in rehabilitation and helping people to recover after neurological conditions.
In particular, it demonstrates that very consistent lead-in movements with the same distance and duration are required to get the best possible recall of a skilled action.
The research, published in the journal PLOS ONE, saw two groups of people asked to complete a movement task after being subjected to a series of different physical and visual triggers.
It was led by Dr Ian Howard, Associate Professor in Computational Neuroscience in the University of Plymouth's School of Engineering, Computing and Mathematics, with colleagues Professor David Franklin and Dr Sae Franklin at the Technical University of Munich, Germany.
Dr Howard has previously carried out research showing that a consistent backswing is crucial in helping sports people produce optimum results, while the follow-through performed after completing an action has significant influence on the extent to which new skills are acquired.
Speaking about the latest research, he said: "In our daily lives we often make what seem like simple actions but are in fact comprised of complex and connected movements. Drinking a cup of coffee, for example, involves the brain knowing where the cup is, reaching for it, bringing it to our mouths and then drinking it in a controlled way. Our brains become trained to do this over time but understanding how, and what might influence their ability to do this, is something scientists have been trying to figure out for many years.
"Our findings suggest that the distance, speed and duration of movements significantly affect how we recall different motions. We believe it is important for those trying to understand how the brain functions. However, it is particularly significant for those working in rehabilitation and other similar fields helping people to recover from neurological conditions. It indicated that lead-in during training must be consistent and similar to lead-in during later use."
For the study, participants learned to compensate a curl force field using a two-part point-to-point movement task. The first part was either a passive lead-in movement or a visual lead-in movement (observation of a moving cursor).
Participants made the second movement themselves and did so in a curl field. The curl field pushed their hand in a direction perpendicular to movement, proportional to their speed of movement. After they learned to move normally again in the curl field, the duration and distance of the lead-in movement were occasionally changed.
This significantly affected their performance in the curl field, and indeed, some lead-in durations and distances almost removed the effect of the previous training.
https://www.sciencedaily.com/releases/2020/01/200130091530.htm
Antianxiety and antidepressant effects from a single dose of psychedelic drug persist years later in cancer patients
January 28, 2020
Science Daily/New York University
Following up on their landmark 2016 study, researchers at NYU Grossman School of Medicine found that a one-time, single-dose treatment of psilocybin, a compound found in psychedelic mushrooms, combined with psychotherapy appears to be associated with significant improvements in emotional and existential distress in cancer patients. These effects persisted nearly five years after the drug was administered.
In the original study, published in the Journal of Psychopharmacology, psilocybin produced immediate, substantial, and sustained improvements in anxiety and depression and led to decreases in cancer-related demoralization and hopelessness, improved spiritual well-being, and increased quality of life. At the final 6.5-month follow-up assessment, psilocybin was associated with enduring antianxiety and antidepressant effects. Approximately 60 percent to 80 percent of participants continued with clinically significant reductions in depression or anxiety, sustained benefits in existential distress and quality of life, as well as improved attitudes toward death.
The present study, publishing online Jan. 28 in the same journal, is a long-term follow-up (with assessments at about 3 years and 4.5 years following single-dose psilocybin administration) of a subset of participants from the original trial. The study reports on sustained reductions in anxiety, depression, hopelessness, demoralization, and death anxiety at both follow-up points.
Approximately 60 percent to 80 percent of participants met criteria for clinically significant antidepressant or anxiolytic responses at the 4.5 year follow-up. Participants overwhelmingly (71 to 100 percent) attributed positive life changes to the psilocybin-assisted therapy experience and rated it among the most personally meaningful and spiritually significant experiences of their lives.
"Adding to evidence dating back as early as the 1950s, our findings strongly suggest that psilocybin therapy is a promising means of improving the emotional, psychological, and spiritual well-being of patients with life-threatening cancer," says the 2016 parent study's lead investigator, Stephen Ross, MD, an associate professor of psychiatry in the Department of Psychiatry at NYU Langone Health. "This approach has the potential to produce a paradigm shift in the psychological and existential care of patients with cancer, especially those with terminal illness."
An alternative means of treating cancer-related anxiety and depression is urgently needed, says Ross. According to statistics from several sources, close to 40 percent of the global population will be diagnosed with cancer in their lifetime, with a third of those individuals developing anxiety, depression, and other forms of distress as a result. These conditions, experts say, are associated with poorer quality of life, increased rates of suicide, and lowered survival rate. Unfortunately, conventional pharmacologic treatment methods like antidepressants work for less than half of cancer patients and tend to not work any better than placebos. In addition, they have no effect whatsoever on existential distress and death anxiety, which commonly accompany a cancer diagnosis and are linked to a hastened desire for death and increased suicidality, says Ross.
The researchers say psilocybin may provide a useful tool for enhancing the effectiveness of psychotherapy and ultimately relieving these symptoms. Although the precise mechanisms are not fully understood, experts believe that the drug can make the brain more flexible and receptive to new ideas and thought patterns. In addition, previous research indicates that the drug targets a network of the brain, the default mode network, which becomes activated when we engage in self-reflection and mind wandering, and which helps to create our sense of self and sense of coherent narrative identity. In patients with anxiety and depression, this network becomes hyperactive and is associated with rumination, worry, and rigid thinking. Psilocybin appears to acutely shift activity in this network and helps people to take a more broadened perspective on their behaviors and lives.
How the Original Research and Follow-up Were Conducted
For the original study, the NYU Langone team provided 29 cancer patients with nine psychotherapy sessions, as well a single dose of either psilocybin or an active placebo, niacin, which can produce a physical flush sensation that mimics a psychedelic drug experience. After seven weeks, all participants swapped treatments and were monitored with clinical outcome measures for anxiety, depression, and existential distress, among other factors.
Although researchers found that the treatment's antianxiety and antidepressant qualities persisted 6.5 months after the intervention, little was known of the drug's effectiveness in the long term. The new follow-up study is the longest-spanning exploration of psilocybin's effects on cancer-related psychiatric distress to date, the study authors say.
"These results may shed light on how the positive effects of a single dose of psilocybin persist for so long," says Gabby Agin-Liebes, PhD candidate, lead investigator and lead author of the long-term follow-up study, and co-author of the 2016 parent study. "The drug seems to facilitate a deep, meaningful experience that stays with a person and can fundamentally change his or her mindset and outlook," she says.
Agin-Liebes, who is pursuing her PhD in clinical psychology at Palo Alto University in California, cautions that psilocybin does not inherently lead to positive therapeutic effects when used in isolation, and in uncontrolled, recreational settings, and "should be taken in a controlled and psychologically safe setting, preferably in conjunction with counseling from trained mental health practitioners or facilitators," she adds.
Next, the researchers plan to expand this research with larger trials in patients from diverse socioeconomic and ethnic groups who have advanced cancer-related psychiatric and existential distress.
"This could profoundly transform the psycho-oncologic care of patients with cancer, and importantly could be used in hospice settings to help terminally ill cancer patients approach death with improved emotional and spiritual well-being," says Ross.
https://www.sciencedaily.com/releases/2020/01/200128115423.htm
Walnuts may slow cognitive decline in at-risk elderly
Two-year study examined walnut consumption among study groups in California and Spain
January 28, 2020
Science Daily/Loma Linda University Adventist Health Sciences Center
Eating walnuts may help slow cognitive decline in at-risk groups of the elderly population, according to a study conducted by researchers in California and Spain.
The Walnuts and Healthy Aging Study, published this month in The American Journal of Clinical Nutrition, found that walnut consumption by healthy, elderly adults had little effect on cognitive function over two years, but it had greater effect on elderly adults who had smoked more and had a lower baseline neuropsychological test scores.
The study examined nearly 640 free-living elders in Loma Linda, California, USA, and in Barcelona, Catalonia, Spain. For two years, the test group included walnuts in their daily diet, and the control group abstained from walnuts.
Walnuts contain omega-3 fatty acids and polyphenols, which have previously been found to counteract oxidative stress and inflammation, both of which are drivers of cognitive decline.
Joan Sabaté, MD, DrPH, professor of nutrition and epidemiology at Loma Linda University School of Public Health and the study's principal investigator, said this was the largest and most well-controlled trial ever conducted on the effects of nuts on cognition.
"While this was a minor result, it could lead to better outcomes when conducted over longer periods of time," Sabaté said. "Further investigation is definitely warranted based on our findings, especially for disadvantaged populations, who may have the most to gain from incorporating walnuts and other nuts into their diet."
Sabaté and his research team at Loma Linda University were the first to discover the cholesterol-lowering effect of nut consumption -- specifically walnuts -- with lowering blood cholesterol. Findings were first published in the New England Journal of Medicine in 1993.
Subsequently, findings from Loma Linda University researchers have linked nut consumption to lower risk of cardiovascular diseases.
The Walnuts and Healthy Aging Study was funded by a grant from the California Walnut Commission, which had no input in the study design, data collection, analyses, or writing and submission of the manuscript.
https://www.sciencedaily.com/releases/2020/01/200128080917.htm
Can lithium halt progression of Alzheimer's disease?
Researchers' findings show that may be the case
January 25, 2020
Science Daily/McGill University
In a new study, a team of researchers has shown that, when given in a formulation that facilitates passage to the brain, lithium in doses up to 400 times lower than what is currently being prescribed for mood disorders is capable of both halting signs of advanced Alzheimer's pathology and of recovering lost cognitive abilities.
There remains a controversy in scientific circles today regarding the value of lithium therapy in treating Alzheimer's disease. Much of this stems from the fact that because the information gathered to date has been obtained using a multitude of differential approaches, conditions, formulations, timing and dosages of treatment, results are difficult to compare. In addition, continued treatments with high dosage of lithium render a number of serious adverse effects making this approach impracticable for long term treatments especially in the elderly.
In a new study, however, a team of researchers at McGill University led by Dr. Claudio Cuello of the Department of Pharmacology and Therapeutics, has shown that, when given in a formulation that facilitates passage to the brain, lithium in doses up to 400 times lower than what is currently being prescribed for mood disorders is capable of both halting signs of advanced Alzheimer's pathology such as amyloid plaques and of recovering lost cognitive abilities. The findings are published in the most recent edition of the Journal of Alzheimer's Disease.
Building on their previous work
"The recruitment of Edward Wilson, a graduate student with a solid background in psychology, made all the difference," explains Dr. Cuello, the study's senior author, reflecting on the origins of this work. With Wilson, they first investigated the conventional lithium formulation and applied it initially in rats at a dosage similar to that used in clinical practice for mood disorders. The results of the initial tentative studies with conventional lithium formulations and dosage were disappointing however, as the rats rapidly displayed a number of adverse effects. The research avenue was interrupted but renewed when an encapsulated lithium formulation was identified that was reported to have some beneficial effects in a Huntington disease mouse model.
The new lithium formulation was then applied to a rat transgenic model expressing human mutated proteins causative of Alzheimer's, an animal model they had created and characterized. This rat develops features of the human Alzheimer's disease, including a progressive accumulation of amyloid plaques in the brain and concurrent cognitive deficits.
"Microdoses of lithium at concentrations hundreds of times lower than applied in the clinic for mood disorders were administered at early amyloid pathology stages in the Alzheimer's-like transgenic rat. These results were remarkably positive and were published in 2017 in Translational Psychiatry and they stimulated us to continue working with this approach on a more advanced pathology," notes Dr. Cuello.
Encouraged by these earlier results, the researchers set out to apply the same lithium formulation at later stages of the disease to their transgenic rat modelling neuropathological aspects of Alzheimer's disease. This study found that beneficial outcomes in diminishing pathology and improving cognition can also be achieved at more advanced stages, akin to late preclinical stages of the disease, when amyloid plaques are already present in the brain and when cognition starts to decline.
"From a practical point of view our findings show that microdoses of lithium in formulations such as the one we used, which facilitates passage to the brain through the brain-blood barrier while minimizing levels of lithium in the blood, sparing individuals from adverse effects, should find immediate therapeutic applications," says Dr. Cuello. "While it is unlikely that any medication will revert the irreversible brain damage at the clinical stages of Alzheimer's it is very likely that a treatment with microdoses of encapsulated lithium should have tangible beneficial effects at early, preclinical stages of the disease."
Moving forward
Dr. Cuello sees two avenues to build further on these most recent findings. The first involves investigating combination therapies using this lithium formulation in concert with other interesting drug candidates. To that end he is pursuing opportunities working with Dr. Sonia Do Carmo, the Charles E. Frosst-Merck Research Associate in his lab.
He also believes that there is an excellent opportunity to launch initial clinical trials of this formulation with populations with detectable preclinical Alzheimer's pathology or with populations genetically predisposed to Alzheimer's, such as adult individuals with Down Syndrome. While many pharmaceutical companies have moved away from these types of trials, Dr. Cuello is hopeful of finding industrial or financial partners to make this happen, and, ultimately, provide a glimmer of hope for an effective treatment for those suffering from Alzheimer's disease.
https://www.sciencedaily.com/releases/2020/01/200125090727.htm
Living near major roads linked to risk of dementia, Parkinson's, Alzheimer's and MS
January 23, 2020
Science Daily/University of British Columbia
Living near major roads or highways is linked to higher incidence of dementia, Parkinson's disease, Alzheimer's disease and multiple sclerosis (MS), suggests new research published this week in the journal Environmental Health.
Researchers from the University of British Columbia analyzed data for 678,000 adults in Metro Vancouver. They found that living less than 50 metres from a major road or less than 150 metres from a highway is associated with a higher risk of developing dementia, Parkinson's, Alzheimer's and MS -- likely due to increased exposure to air pollution.
The researchers also found that living near green spaces, like parks, has protective effects against developing these neurological disorders.
"For the first time, we have confirmed a link between air pollution and traffic proximity with a higher risk of dementia, Parkinson's, Alzheimer's and MS at the population level," says Weiran Yuchi, the study's lead author and a PhD candidate in the UBC school of population and public health. "The good news is that green spaces appear to have some protective effects in reducing the risk of developing one or more of these disorders. More research is needed, but our findings do suggest that urban planning efforts to increase accessibility to green spaces and to reduce motor vehicle traffic would be beneficial for neurological health."
Neurological disorders -- a term that describes a range of disorders, including Alzheimer's disease and other dementias, Parkinson's disease, multiple sclerosis and motor neuron diseases -- are increasingly recognized as one of the leading causes of death and disability worldwide. Little is known about the risk factors associated with neurological disorders, the majority of which are incurable and typically worsen over time.
For the study, researchers analyzed data for 678,000 adults between the ages of 45 and 84 who lived in Metro Vancouver from 1994 to 1998 and during a follow-up period from 1999 to 2003. They estimated individual exposures to road proximity, air pollution, noise and greenness at each person's residence using postal code data. During the follow-up period, the researchers identified 13,170 cases of non-Alzheimer's dementia, 4,201 cases of Parkinson's disease, 1,277 cases of Alzheimer's disease and 658 cases of MS.
For non-Alzheimer's dementia and Parkinson's disease specifically, living near major roads or a highway was associated with 14 per cent and seven per cent increased risk of both conditions, respectively. Due to relatively low numbers of Alzheimer's and MS cases in Metro Vancouver compared to non-Alzheimer's dementia and Parkinson's disease, the researchers did not identify associations between air pollution and increased risk of these two disorders. However, they are now analyzing Canada-wide data and are hopeful the larger dataset will provide more information on the effects of air pollution on Alzheimer's disease and MS.
When the researchers accounted for green space, they found the effect of air pollution on the neurological disorders was mitigated. The researchers suggest that this protective effect could be due to several factors.
"For people who are exposed to a higher level of green space, they are more likely to be physically active and may also have more social interactions," said Michael Brauer, the study's senior author and professor in the UBC school of population and public health. "There may even be benefits from just the visual aspects of vegetation."
Brauer added that the findings underscore the importance for city planners to ensure they incorporate greenery and parks when planning and developing residential neighbourhoods.
https://www.sciencedaily.com/releases/2020/01/200123152616.htm
Possible Alzheimer's breakthrough suggested
January 22, 2020
Science Daily/Case Western Reserve University
Researchers at the Case Western University School of Medicine say they have identified a previously unknown gene and associated protein which could potentially be suppressed to slow the advance of Alzheimer's disease.
"Based on the data we have, this protein can be an unrecognized new risk factor for Alzheimer's disease (AD)," said Xinglong Wang, an associate professor of pathology at the School of Medicine. "We also see this as a potential novel therapeutic target for this devastating disease."
Wang said proving the latter assertion, which has not yet been tested in humans, would require additional research to corroborate the function of the protein they have dubbed "aggregatin." Eventually, that would someday mean clinical trials with Alzheimer's patients, he said.
"This protein characteristically accumulates, or aggregates, within the center of plaque in AD patients, like the yolk of an egg -- which is part of the reason we named it "aggregatin," Wang said.
A research team led by Wang and Xiaofeng Zhu, a professor of Population and Quantitative Health Sciences at the School of Medicine, has filed for a patent through the university's Office of Research and Technology Management for "novel Alzheimer's disease treatments and diagnosis based on this and related study," Wang said.
"We're very excited about this because our study is likely the first systematic work combining the identification from a genome-wide association study of high dimensional brain-imaging data and experimental validation so perfectly in Alzheimer's disease," Zhu said.
Their research was published this month by the scientific journal Nature Communications and supported by grants from the National Institutes of Health (NIH) and the Alzheimer's Association. Genomic and brain imaging data was obtained from the Alzheimer's Disease Neuroimaging Initiative, which is supported by the NIH.
Alzheimer's Disease affects millions
More than 5.7 million Americans have Alzheimer's disease, which is the primary cause of dementia and sixth-leading cause of death in the United States. That population is predicted to reach 14 million by the year 2050, according to the Alzheimer's Association.
The relationship between Alzheimer's (and subsequent brain atrophy) and amyloid plaques -- the hard accumulations of beta amyloid proteins that clump together between the nerve cells (neurons) in the brains of Alzheimer's patients -- has been well-established among researchers.
Less understood is precisely how that amyloid-beta actually leads to plaque formation -- and where this new work appears to have broken new ground, Wang said.
Further, while there has been much research into what genes might influence whether or not someone gets Alzheimer's, there is less understanding of genes that might be linked to the progression of the disease, meaning the formation of plaque and subsequent atrophy in the brain.
The role of 'aggregatin' protein
In the new work, the researchers began by correlating roughly a million genetic markers (called single-nucleotide polymorphisms, or SNPs) with brain images. They were able to identify a specific SNP in the FAM222, a gene linked to different patterns of regional brain atrophy.
Further experiments then suggested that the protein encoded by gene FAM222A is not only associated with AD patient-related beta-amyloid plaques and regional brain atrophy, but that "aggregatin" attaches to amyloid beta peptide -- the major component of plaque and facilitates the plaque formation.
So when researchers injected mouse models with the "aggregatin" protein (made from the FAM222A gene), plaque (amyloid deposits) formation accelerated in the brain, resulting in more neuroinflammation and cognitive dysfunction. This happened, they report, because the protein was found to bind directly the amyloid beta peptide, thus facilitating the aggregation and placque formation, Wang said.
Conversely, when they suppressed the protein, the plaques were reduced and neuroinflammation and cognitive impairment alleviated.
Their findings indicate that reducing levels of this protein and inhibition of its interaction with amyloid beta peptide could potentially be therapeutic -- not necessarily to prevent Alzheimer's but to slow its progression.
https://www.sciencedaily.com/releases/2020/01/200122080532.htm
Blue light triggers memory and emphatic fear in mice via a non-invasive approach
January 21, 2020
Science Daily/Institute for Basic Science
Researchers at the Center for Cognition and Sociality, within the Institute for Basic Science (IBS) in South Korea, have engineered an improved biological tool that controls calcium (Ca2+) levels in the brain via blue light. Published in Nature Communications, this optogenetic construct, called monster-OptoSTIM1 or monSTIM1 for short, causes a change in mice's fear learning behavior without the need of optic fiber implants in the brain.
The brain utilizes Ca2+ signaling to regulate a variety of functions, including memory, emotion, and movement. Several evidences show correlation between abnormally regulated Ca2+ levels in certain brain cells and neurodegenerative diseases, but the details still remain obscure. For understanding the precise role of Ca2+ signaling, the IBS team is studying Ca2+-specific modulators that can be triggered in different parts of the brain at a designated time.
Optogenetics uses light to control Ca2+ signaling in the mouse brain. Since the brain is surrounded by hair, skin and skull, which prevent light from reaching deep tissues, optic fiber insertion in the brain used to be the norm in optogenetics. However, these implants can cause inflammation, morphological changes of neurons and disconnection of neural circuits. In this study, the research team improved their optogenetic tool so that it works with an external source of blue light, shone from the ceiling of the mouse cage, and without the need of brain implants.
MonSTIM1 is made of a part (CRY2) that responds to blue light and another part (STIM1) that activates calcium channels. Compared to the previously developed optogenetic techniques, the researchers were able to enhance CRY2's light-sensitivity approximately 55-fold and also avoid the increase of basal Ca2+ levels. The monSTIM1 construct was injected into the mouse brain through a virus, and was shown to activate Ca2+ signals in the cortex as well as in the deeper hippocampus and thalamus regions.
The team observed behavioral changes in mice with monSTIM1 expressed in excitatory neurons in the anterior cingulate cortex, a brain region that has a central function in empathic emotions. Mice with activated monSTIM1 froze with fear by looking at other mice, which experienced a mild electric foot shock. Twenty-four hours later the same mice remembered about it and showed again an enhanced fear response, indicating that Ca2+ signaling contributed to both short- and long-term social fear responses.
"MonSTIM1 can be applied to a wide range of brain calcium research and brain cognitive science research, because it allows easy manipulation of intracellular calcium signals without damaging the brain," says Won Do Heo (KAIST professor), leading author of this research.
https://www.sciencedaily.com/releases/2020/01/200121123953.htm
America's most widely consumed oil causes genetic changes in the brain
Soybean oil linked to metabolic and neurological changes in mice
January 17, 2020
Science Daily/University of California - Riverside
New UC Riverside research shows soybean oil not only leads to obesity and diabetes, but could also affect neurological conditions like autism, Alzheimer's disease, anxiety, and depression.
Used for fast food frying, added to packaged foods, and fed to livestock, soybean oil is by far the most widely produced and consumed edible oil in the U.S., according to the U.S. Department of Agriculture. In all likelihood, it is not healthy for humans.
It certainly is not good for mice. The new study, published this month in the journal Endocrinology, compared mice fed three different diets high in fat: soybean oil, soybean oil modified to be low in linoleic acid, and coconut oil.
The same UCR research team found in 2015 that soybean oil induces obesity, diabetes, insulin resistance, and fatty liver in mice. Then in a 2017 study, the same group learned that if soybean oil is engineered to be low in linoleic acid, it induces less obesity and insulin resistance.
However, in the study released this month, researchers did not find any difference between the modified and unmodified soybean oil's effects on the brain. Specifically, the scientists found pronounced effects of the oil on the hypothalamus, where a number of critical processes take place.
"The hypothalamus regulates body weight via your metabolism, maintains body temperature, is critical for reproduction and physical growth as well as your response to stress," said Margarita Curras-Collazo, a UCR associate professor of neuroscience and lead author on the study.
The team determined a number of genes in mice fed soybean oil were not functioning correctly. One such gene produces the "love" hormone, oxytocin. In soybean oil-fed mice, levels of oxytocin in the hypothalamus went down.
The research team discovered roughly 100 other genes also affected by the soybean oil diet. They believe this discovery could have ramifications not just for energy metabolism, but also for proper brain function and diseases such as autism or Parkinson's disease. However, it is important to note there is no proof the oil causes these diseases.
Additionally, the team notes the findings only apply to soybean oil -- not to other soy products or to other vegetable oils.
"Do not throw out your tofu, soymilk, edamame, or soy sauce," said Frances Sladek, a UCR toxicologist and professor of cell biology. "Many soy products only contain small amounts of the oil, and large amounts of healthful compounds such as essential fatty acids and proteins."
A caveat for readers concerned about their most recent meal is that this study was conducted on mice, and mouse studies do not always translate to the same results in humans.
Also, this study utilized male mice. Because oxytocin is so important for maternal health and promotes mother-child bonding, similar studies need to be performed using female mice.
One additional note on this study -- the research team has not yet isolated which chemicals in the oil are responsible for the changes they found in the hypothalamus. But they have ruled out two candidates. It is not linoleic acid, since the modified oil also produced genetic disruptions; nor is it stigmasterol, a cholesterol-like chemical found naturally in soybean oil.
Identifying the compounds responsible for the negative effects is an important area for the team's future research.
"This could help design healthier dietary oils in the future," said Poonamjot Deol, an assistant project scientist in Sladek's laboratory and first author on the study.
"The dogma is that saturated fat is bad and unsaturated fat is good. Soybean oil is a polyunsaturated fat, but the idea that it's good for you is just not proven," Sladek said.
Indeed, coconut oil, which contains saturated fats, produced very few changes in the hypothalamic genes.
"If there's one message I want people to take away, it's this: reduce consumption of soybean oil," Deol said about the most recent study.
https://www.sciencedaily.com/releases/2020/01/200117080827.htm
Exosomes promote remarkable recovery in stroke
January 14, 2020
Science Daily/University of Georgia
Scientists present brain-imaging data for a new stroke treatment that supported full recovery in swine, modeled with the same pattern of neurodegeneration as seen in humans with severe stroke.
It's been almost a quarter century since the first drug was approved for stroke. But what's even more striking is that only a single drug remains approved today.
In a publication appearing this month in the journal Translational Stroke Research, animal scientists, funded by the National Institutes of Health, present brain-imaging data for a new stroke treatment that supported full recovery in swine, modeled with the same pattern of neurodegeneration as seen in humans with severe stroke.
"It was eye opening and unexpected that you would see such a benefit after having had such a severe stroke," said Steven Stice, Georgia Research Alliance Eminent Scholar and D.W. Brooks Distinguished Professor in the University of Georgia's College of Agricultural and Environmental Sciences. "Perhaps the most formidable discovery was that one could recover and do so well after the exosome treatment."
Stice and his colleagues at UGA's Regenerative Bioscience Center report the first observational evidence during a midline shift -- when the brain is being pushed to one side -- to suggest that a minimally invasive and non-operative exosome treatment can now influence the repair and damage that follow a severe stroke.
Exosomes are considered to be powerful mediators of long-distance cell-to-cell communication that can change the behavior of tumor and neighboring cells. The results of the study echo findings from other recent RBC studies using the same licensed exosome technology.
Many patients who suffer stroke exhibit a shift of the brain past its center line -- the valley between the left and right part of the brain. Lesions or tumors will induce pressure or inflammation in the brain, causing what typically appears as a straight line to shift.
"Based on results of the exosome treatment in swine, it doesn't look like lesion volume or the effects of a midline shift matter nearly as much as one would think," said Franklin West, associate professor of animal and dairy science in the UGA College of Agricultural and Environmental Sciences. "This suggests that, even in some extremely severe cases caused by stroke, you're still going to recover just as well."
Trauma from an acute stroke can happen quickly and can cause irreversible damage almost immediately. "Time is brain," a phrase coined by stroke advocacy organizations in the late 1990s, captures the importance of acting on the first signs of stroke. In less than 60 seconds, warns the Stroke Awareness Foundation, an ischemic stroke kills 1.9 million brain cells.
Data from the team's research showed that non-treated brain cells near the site of the stroke injury quickly starved from lack of oxygen and died -- triggering a lethal action of damage signals throughout the brain network and potentially compromising millions of healthy cells.
However, in brain areas treated with exosomes that were taken directly from cold storage and administered intravenously, these cells were able to penetrate the brain and interrupt the process of cell death.
"Basically, during a stroke, these really destructive free radicals are all over the place destroying things," said Stice, director of the RBC. "What the exosome technology does is communicate with jeopardized cells and work like an anti-inflammatory agent to interrupt and stop further damage."
According to the team's results, neuroimaging is an essential tool for evaluating brain tissue and managing stroke recovery.
In this observational study, the team analyzed brain images taken 24 hours after stroke. They then applied recovery scores, commonly used in human practice, based on swine gait, cadence, walking speed and stride length. By recording the relationship between brain measurements and functional outcomes, the new assessment scales can better help physicians predict how quickly a person will recover in real time.
"What I'm trying to do with this assessment data is come up with something that we can implement in the clinics right now -- today -- to help with predicting patient outcomes," said Samantha Spellicy, a neuroscience graduate student and first author on the publication.
Spellicy, who is currently training under Stice, began her first two years at the Medical College of Georgia at Augusta University and has plans to return to MCG after completing her Ph.D. She anticipates a return to stroke care and one day using the same outcome assessments presented in the study with human patients.
"When a patient arrives in emergency with a stroke, the available clinician would not be left crunching an arbitrary number based on some standardized scale assessment," Spellicy said. "Instead, the clinician could take more of a personalized approach based on the patient's midline shift measurement, and, say for instance, 'OK, in three months you're going to get better, but you're going to have issues with your gait. Let's talk to a specialist now to target that exact condition.'"
As for the future of the exosome treatment, Spellicy and the RBC team anticipate that the patented neural exosome technology, called AB126, will be filed for clinical trials by 2021.
https://www.sciencedaily.com/releases/2020/01/200114125924.htm