Does eating fish protect our brains from air pollution?
July 15, 2020
Science Daily/American Academy of Neurology
Older women who eat more than one to two servings a week of baked or broiled fish or shellfish may consume enough omega-3 fatty acids to counteract the effects of air pollution on the brain, according to a new study published in the July 15, 2020, online issue of Neurology®, the medical journal of the American Academy of Neurology.
Researchers found that among older women who lived in areas with high levels of air pollution, those who had the lowest levels of omega-3 fatty acids in their blood had more brain shrinkage than women who had the highest levels.
"Fish are an excellent source of omega-3 fatty acids and easy to add to the diet," said study author Ka He, M.D., Sc.D., of Columbia University in New York. "Omega-3 fatty acids have been shown to fight inflammation and maintain brain structure in aging brains. They have also been found to reduce brain damage caused by neurotoxins like lead and mercury. So we explored if omega-3 fatty acids have a protective effect against another neurotoxin, the fine particulate matter found in air pollution."
The study involved 1,315 women with an average age of 70 who did not have dementia at the start of the study. The women completed questionnaires about diet, physical activity, and medical history.
Researchers used the diet questionnaire to calculate the average amount of fish each woman consumed each week, including broiled or baked fish, canned tuna, tuna salad, tuna casserole and non-fried shellfish. Fried fish was not included because research has shown deep frying damages omega-3 fatty acids.
Participants were given blood tests. Researchers measured the amount of omega-3 fatty acids in their red blood cells and then divided the women into four groups based on the amount of omega-3 fatty acids in their blood.
Researchers used the women's home addresses to determine their three-year average exposure to air pollution. Participants then had brain scans with magnetic resonance imaging (MRI) to measure various areas of the brain including white matter, which is composed of nerve fibers that send signals throughout the brain, and the hippocampus, the part of the brain associated with memory.
After adjusting for age, education, smoking and other factors that could affect brain shrinkage, researchers found that women who had the highest levels of omega-3 fatty acids in the blood had greater volumes of white matter than those with the lowest levels. Those in the highest group had 410 cubic centimeters (cm3) white matter, compared to 403 cm3 for those in the lowest group. The researchers found that for each quartile increase in air pollution levels, the average white matter volume was 11.52 cm3 smaller among people with lower levels of omega-3 fatty acids and 0.12 cm3 smaller among those with higher levels.
Women with the highest levels of omega-3 fatty acids in the blood also had greater volumes of the hippocampus.
"Our findings suggest that higher levels of omega-3 fatty acids in the blood from fish consumption may preserve brain volume as women age and possibly protect against the potential toxic effects of air pollution," said He. "It's important to note that our study only found an association between brain volume and eating fish. It does not prove that eating fish preserves brain volume. And since separate studies have found some species of fish may contain environmental toxins, it's important to talk to a doctor about what types of fish to eat before adding more fish to your diet."
A limitation of the study was that most participants were older white women, so the results cannot be generalized to others. Also, researchers were only able to examine exposures to later-life air pollution, not early or mid-life exposures, so future studies should look at exposures to air pollution across a person's lifespan.
https://www.sciencedaily.com/releases/2020/07/200715163555.htm
Nutrients in microalgae: An environmentally friendly alternative to fish
July 7, 2020
Science Daily/Martin-Luther-Universität Halle-Wittenberg
Microalgae could provide an alternative source of healthy omega-3 fatty acids for humans while also being more environmentally friendly to produce than popular fish species. This is the result of a new study by scientists from Martin Luther University Halle-Wittenberg (MLU). The study was recently published in the Journal of Applied Phycology and offers an initial indication of the environmental effects of producing microalgae in Germany.
Microalgae have been the focus of several decades of research -- initially as a raw material for alternative fuels, but more recently as a source of nutrients in the human diet. They are mainly produced in open ponds in Asia; however, these ponds are at risk of potential contamination. Also, some species of algae are easier to cultivate in closed systems, so-called photobioreactors. "We wanted to figure out whether microalgae produced in photobioreactors in Germany could provide a more environmentally friendly source of essential nutrients than fish," says Susann Schade from the Institute of Agricultural and Nutritional Sciences at MLU. Up to now, photobioreactors had usually only been compared to pond cultivation and they often scored worse due to their higher environmental impacts. "However, little research has been done on the precise extent of the environmental impacts of algae produced for human consumption, especially under climatic conditions such as those found in Germany," adds Schade.
For their study, the researchers developed a model to determine location-specific environmental impacts. "One of the things we did was to compare the carbon footprint of nutrients from microalgae and fish. We also analysed how much both food sources increase the acidification and eutrophication in water bodies," explains Dr Toni Meier, head of the Innovation Office nutriCARD at MLU. The researchers were able to show that microalgae farming has a similar impact on the environment as fish production. "However, if we compare the environmental effects in relation to the amount of omega-3 fatty acids produced, fish from aquaculture comes off far worse," says Schade. One advantage of algae cultivation is its low land consumption; even infertile soils can be used. In contrast, both open ponds and the cultivation of feed for aquaculture require very large areas of land. In particular, fish species that are popular in Germany, such as salmon and pangasius, are primarily produced through aquaculture and therefore put the environment under a considerable amount of pressure. However, even fishing wild Alaska pollack had poorer values than microalgae for all environmental indicators.
"Microalgae should not and cannot completely replace fish as a food source. But if microalgae could be established as a common food, it would be another excellent environmentally friendly source of long-chain omega-3 fatty acids," explains Meier. Several algae are already used as a food supplement in powder or tablet form and as an additive to foods such as pasta or cereals. It would be a way to reduce the current gap in the global supply of omega-3 fatty acids. At the same time, it would provide considerable relief to the world's oceans.
https://www.sciencedaily.com/releases/2020/07/200707084008.htm
Analysis predicts purified fish oil could prevent thousands of cardiovascular events
March 25, 2020
Science Daily/University of California - Irvine
Researchers from the University of California, Irvine have conducted a statistical analysis that predicts more than 70,000 heart attacks, strokes and other adverse cardiovascular events could be prevented each year in the U.S. through the use of a highly purified fish oil therapy.
Led by Nathan D. Wong, PhD, professor and director of the Heart Disease Prevention Program in the Division of Cardiology at the UCI School of Medicine, the abstract of the statistical analysis was accepted by the American College of Cardiology and is slated to be presented at the upcoming ACC.20/World Congress of Cardiology virtual conference taking place March 28-30. The analysis utilizes data from the Centers for Disease Control and Prevention's National Health and Nutrition Examination Survey (NHANES), and inclusion criteria from a multinational clinical trial led by investigators from Harvard University called REDUCE-IT, which was published in the New England Journal of Medicine in January of 2019.
The REDUCE-IT trial showed patients with known cardiovascular disease or diabetes and multiple risk factors who have elevated triglyceride levels and are at increased risk for ischemic events benefitted substantially from icosapent ethyl, a highly purified fish oil therapy, which lowered cardiovascular events, including heart attacks and strokes, by 25 percent. Positive results were not found in other trials, possibly due to mixtures with other omega-3 fatty acids such as DHA, or inadequate dosages according to Wong.
"Our analysis extends the findings of the REDUCE-IT trial by estimating its potential impact on the U.S. population," said Wong. "By using inclusion criteria and cardiovascular disease event rates from the REDUCE-IT trial and applying it to data on US adults from NHANES, we were able to estimate the beneficial impact icosapent ethyl could have on preventing initial and total cardiovascular events in eligible U.S. adults with cardiovascular disease or diabetes and multiple risk factors."
Wong's analysis is the first to project the findings of REDUCE-IT to the overall U.S. population.
"When you consider that for every 21 patients treated with icosapent ethyl you can spare a cardiovascular event, you begin to see the implications of our results," said Wong.
Icosapent ethyl is a purified stable eicosapentaenoic acid (EPA) which was recently approved by the Federal Drug Administration (FDA) in conjunction with maximally tolerated statin therapy to reduce the risk of cardiovascular events in certain adults with elevated triglyceride levels. The only drug of its kind to show such an effect, icosapent ethyl, is currently marketed under the name Vascepa® by Amarin Pharma. The EPA therapy has also gained the support of several major societies, which have incorporated it in various guidelines, scientific statements and advisories, including the American Diabetes Association, American Heart Association, National Lipid Association, and the European Society of Cardiology/European Atherosclerosis Society.
https://www.sciencedaily.com/releases/2020/03/200325131536.htm
Products of omega-3 fatty acid metabolism may have anticancer effects
July 13, 2018
Science Daily/University of Illinois at Urbana-Champaign
A class of molecules formed when the body metabolizes omega-3 fatty acids could inhibit cancer's growth and spread, University of Illinois researchers report in a new study in mice. The molecules, called endocannabinoids, are made naturally by the body and have similar properties to cannabinoids found in marijuana -- but without the psychotropic effects.
In mice with tumors of osteosarcoma -- a bone cancer that is notoriously painful and difficult to treat -- endocannabinoids slowed the growth of tumors and blood vessels, inhibited the cancer cells from migrating and caused cancer cell death. The results were published in the Journal of Medicinal Chemistry.
"We have a built-in endocannabinoid system which is anti-inflammatory and pain-reducing. Now we see it is also anti-cancer, stopping the cells from proliferating or migrating," said study leader Aditi Das, a professor of comparative biosciences and an affiliate of biochemistry at Illinois. "These molecules could address multiple problems: cancer, inflammation and pain."
In 2017, the Illinois team identified a new group of omega-3 fatty-acid metabolites called endocannabinoid epoxides, or EDP-EAs. They found that these molecules had anti-inflammatory properties and targeted the same receptor in the body that cannabis does.
Since cannabis has been shown to have some anti-cancer properties, in the new study the researchers investigated whether EDP-EAs also affect cancer cells. They found that in mice with osteosarcoma tumors that metastasized to their lungs, there was an 80 percent increase in naturally occurring EDP-EAs in cancerous lung tissues over the lungs of healthy mice.
"The dramatic increase indicated that these molecules were doing something to the cancer -- but we didn't know if it was harmful or good," Das said. "We asked, are they trying to stop the cancer, or facilitating it? So we studied the individual properties and saw that they are working against the cancer in several ways."
The researchers found that in higher concentrations, EDP-EAs did kill cancer cells, but not as effectively as other chemotherapeutic drugs on the market. However, the compounds also combated the osteosarcoma in other ways: They slowed tumor growth by inhibiting new blood vessels from forming to supply the tumor with nutrients, they prevented interactions between the cells, and most significantly, they appeared to stop cancerous cells from migrating.
"The major cause of death from cancer is driven by the spread of tumor cells, which requires migration of cells," said study coauthor Timothy Fan, a professor of veterinary clinical medicine and veterinary oncology. "As such, therapies that have the potential to impede cell migration also could be useful for slowing down or inhibiting metastases."
The researchers isolated the most potent of the molecules and are working to develop derivatives that bind better to the cannabinoid receptor, which is plentiful on the surface on cancer cells.
"Dietary consumption of omega-3 fatty acids can lead to the formation of these substances in the body and may have some beneficial effects. However, if you have cancer, you want something concentrated and fast acting," Das said. "That's where the endocannabinoid epoxide derivatives come into play -- you could make a concentrated dose of the exact compound that's most effective against the cancer. You could also mix this with other drugs such as chemotherapies."
Next, the researchers plan to perform preclinical studies in dogs, since dogs develop osteosarcoma spontaneously, similarly to humans. They also plan to study the effects of EDP-EAs derived from omega-3 fatty acids in other cancer types.
"Particular cancers that might be most interesting to study would be solid tumors or carcinomas, which tend to spread and cause pain within the skeleton. Some of the most common tumors that behave this way are breast, prostate, and lung carcinomas, and we can certainly explore these tumors in the future," said Fan, who is also a member of the Carle Illinois College of Medicine, the Cancer Center at Illinois and the Carl R. Woese Institute for Genomic Biology.
https://www.sciencedaily.com/releases/2018/07/180713220137.htm
Why fish intake by pregnant women improves the growth of a child's brain
January 14, 2016
Science Daily/Tohoku University
An explanation for the correlation between eating fish during pregnancy, and the health of the baby's brain, has been uncovered by a group of researchers. Dietary lipid contains fatty acids such as omega-6 and omega-3, which are essential nutrients for many animals and humans. The research group found that a balanced intake of lipids by pregnant women is necessary for the normal brain formation of the unborn child.
Dietary lipid contains fatty acids such as omega-6 and omega-3, which are essential nutrients for many animals and humans. The research group, led by Professor Noriko Osumi, found that a balanced intake of lipids by pregnant women is necessary for the normal brain formation of the unborn child.
In an animal study, the researchers noticed that when female mice were fed an omega-6-rich/omega-3-poor diet, their offsprings were born with a smaller brain and showed abnormal emotional behavior in adulthood.
This is significant because people in many countries these days have similarly poor dietary patterns and tend to consume more seed oils that are rich in omega-6 fatty acids and less fish rich in omega-3 fatty acids.
According to Professor Osumi, the brain abnormality found in the offsprings of mice used in the study, was caused by a premature aging of fetal neural stem cells that produce brain cells. The premature aging was promoted by an imbalance of oxides of omega-6 and omega-3 fatty acids. The offsprings also showed higher anxiety levels, even though they were raised on nutritionally optimized diets from an early lactation period.
A diet that contains a good balance of omega-6 and omega-3 fatty acids is known to improve the development of brain functions; this is based on earlier researches that evaluated the effects of maternal intake of an omega-3-poor diet on brain function in children.
The new study took this premise further and focused on the effects of dietary lipids on the brain formation. The results reveal why omega-6 and omega-3 balance is important for future brain function, and reinforces earlier suggestions that more fish intake by women during pregnancy can advantageously affect the child's health.
http://www.sciencedaily.com/releases/2016/01/160114113410.htm
Omega-3 fatty acids fight inflammation via cannabinoids
July 18, 2017
Science Daily/University of Illinois at Urbana-Champaign
Chemical compounds called cannabinoids are found in marijuana and also are produced naturally in the body from omega-3 fatty acids. A well-known cannabinoid in marijuana, tetrahydrocannabinol, is responsible for some of its euphoric effects, but it also has anti-inflammatory benefits. A new study in animal tissue reveals the cascade of chemical reactions that convert omega-3 fatty acids into cannabinoids that have anti-inflammatory benefits - but without the psychotropic high.
Foods such as meat, eggs, fish and nuts contain omega-3 and omega-6 fatty acids, which the body converts into endocannabinoids -- cannabinoids that the body produces naturally, said Aditi Das, a University of Illinois professor of comparative biosciences and biochemistry, who led the study. Cannabinoids in marijuana and endocannabinoids produced in the body can support the body's immune system and therefore are attractive targets for the development of anti-inflammatory therapeutics, she said.
In 1964, the Israeli chemist Raphael Mechoulam was the first to discover and isolate THC from marijuana. To test whether he had found the compound that produces euphoria, he dosed cake slices with 10 milligrams of pure THC and gave them to willing friends at a party. Their reactions, from nonstop laughter, to lethargy, to talkativeness, confirmed that THC was a psychotropic cannabinoid.
It wasn't until 1992 that researchers discovered endocannabinoids produced naturally in the body. Since then, several other endocannabinoids have been identified, but not all have known functions.
Cannabinoids bind to two types of cannabinoid receptors in the body -- one that is found predominantly in the nervous system and one in the immune system, Das said.
"Some cannabinoids, such as THC in marijuana or endocannabinoids can bind to these receptors and elicit anti-inflammatory and anti-pain action," she said.
"Our team discovered an enzymatic pathway that converts omega-3-derived endocannabinoids into more potent anti-inflammatory molecules that predominantly bind to the receptors found in the immune system," Das said. "This finding demonstrates how omega-3 fatty acids can produce some of the same medicinal qualities as marijuana, but without a psychotropic effect."
https://www.sciencedaily.com/releases/2017/07/170718142909.htm
Fish intake associated with boost to antidepressant response
Science Daily/European College of Neuropsychopharmacology (ECNP)
October 20, 2014
Up to half of patients who suffer from major depression do not respond to treatment with Selective Serotonin Reuptake Inhibitors. Now a group of researchers has carried out a study that shows that increasing fatty fish intake appears to increase the response rate in patients who do not respond to antidepressants.
According to lead researcher, Roel Mocking (Amsterdam): "We were looking for biological alterations that could explain depression and antidepressant non-response, so we combined two apparently unrelated measures: metabolism of fatty acids and stress hormone regulation. Interestingly, we saw that depressed patients had an altered metabolism of fatty acids, and that this changed metabolism was regulated in a different way by stress hormones."
The researchers were looking at the relationship between depression and fatty acids, and various hormones, including the stress hormone cortisol. They took 70 patients with depression and compared them to 51 healthy controls, by measuring their fatty acid levels and cortisol levels. They then gave the depressed patients 20mg of an SSRI daily for 6 weeks, and in those who did not respond to the SSRIs the dose was gradually increased up to 50mg/day. Fatty acid and cortisol levels were measured during the trial.
They found that the MDD patients who didn't respond to the SSRI also tended to have abnormal fatty acid metabolism, so they checked the dietary habits of all those taking part in the trial. Fatty fish is rich in fatty acids, such as the well-known Omega-3 DHA. So the researchers looked at the amount of fatty fish in the diet of all involved in the trial. They categorised the patients into 4 groups, according to their fatty fish intake, and they found that those who took the least fish tended to respond badly to anti-depressants, whereas those who had most fish in the diet responded best to anti-depressants. Those who ate fatty fish at least once a week had a 75% chance of responding to antidepressants, whereas those who never ate fatty fish had only a 23% chance of responding to antidepressants.
Roel Mocking continued: "This means that the alterations in fatty acid metabolism (and their relationship with stress hormone regulation) were associated with future antidepressant response. Importantly, this association was associated with eating fatty fish, which is an important dietary source of omega-3 fatty acids. These findings suggest that measures of fatty acid metabolism, and their association with stress hormone regulation, might be of use in the clinic as an early indicator of future antidepressant response. Moreover, fatty acid metabolism could be influenced by eating fish, which may be a way to improve antidepressant response rates."
http://www.sciencedaily.com/releases/2014/10/141020090142.htm