Check out the recipe for making your own low-sodium soy sauce substitute that contains no soy at Low Sodium Soy Sauce Substitute Recipe. The recipe calls for two tablespoons of sodium-free beef bouillon, two tablespoons of red wine vinegar, one teaspoon molasses, 1/8 teaspoon ground ginger, a dash of black pepper and a dash of garlic powder mixed with 3/4 cup of water.
Just mix all these ingredients together and put in in a sauce pan. Then boil uncovered for five minutes until the mixture is reduced by evaporation from the boiling down to just 1/2 cup of liquid. You can store it it the refrigerator when cool. Put it in a covered glass jar. Then shake well or stir before using. The recipe does taste great and makes eight servings.
Some brands of soy sauce contain a large amount of sodium per serving, sometimes -- 920 mg, or 38 percent your maximum daily sodium intake of 2,400 mg. The Mayo Clinic suggests keeping sodium intake to 1,500 mg, especially if you have high blood pressure, kidney disease or diabetes. Sodium can increase blood pressure, which can damage blood vessels and increase the risk of developing heart disease.
The Mayo Clinic recommends avoiding any foods that contain more than 200 mg of sodium per serving. Because the sodium count of soy sauce is so high, use it sparingly and occasionally rather than as a regular condiment, and don't use it at all if you have any risk factors. Or look for low-sodium soy sauce.
Why is it so darn difficult to make healthier hot dogs? See the December 7, 2011 news release from the American Chemical Society, "Shedding light on why it is so 'tough' to make healthier hot dogs."
How healthy can you make a hot dog? What's your personal recipe for making your own hot dogs, regular or vegan? How does it taste, and how healthy are your own home-made hot dogs?
Have you ever had a hot dog headache? Other names for hot dog headache are known as glutamate-induced asthma and/or MSG (monosodium glutamate) syndrome.
In part of an effort to replace animal fat in hot dogs, sausages, hamburgers and other foods with healthier fat, scientists are reporting an advance in solving the mystery of why hot dogs develop an unpleasant tough texture when vegetable oils pinch hit for animal fat. A report on their study appears in ACS' Journal of Agricultural and Food Chemistry (ACS Publications).
Choosing healthier hot dogs for kids
Anna M. Herrero and colleagues explain that some brands of sausage (frankfurters) have been reformulated with olive oil-in-water emulsion as a source of more healthful fat. With consumers gobbling up tens of billions of hot dogs annually, and the typical frankfurter packing 80 percent of its calories from fat, hot dogs have become a prime candidate for reformulation, notes the news release.
Some hot dogs reformulated with vegetable oil develop an unpleasant chewy texture. Herrero's team set out to uncover the chemistry behind that change with an eye to guiding food companies to optimize low-fat sausage manufacture.
Using a laboratory instrument called an infrared spectrometer (IR spectrometer) they verified that sausages made with heart-healthy olive oil-in-water emulsion stabilized with casein were slightly tougher. However, when frankfurters were elaborated with an emulsion stabilized with a combination of casein and microbial transglutaminase (to help the oil blend in better) the sausage became much tougher.
The IR spectrometer revealed that the proteins and fats in low-fat cooked derivates formulated with this stabilizer system as animal fat replacer showed weak lipid-protein interactions, which implies more physical entrapment of the emulsion within the meat matrix. This fact could explain why those sausages are tougher than the others.
The authors acknowledge funding from the Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+I), the Consolider-Ingenio 2010: CARNSENUSA and Ministerio de Ciencia y Tecnología. The American Chemical Society is a non-profit organization chartered by the U.S. Congress.
With more than 163,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.
Meanwhile, what do you do about hot dog headache?
Has hot dog headache made you sleepless? See, The dangers of MSG. Overstimulation of that part of the brain can produce marked changes. Are you worried about the effects of glutamic acid on your brain?
You need both sides of the story, of course. So read the studies from the Glutamate Association which conducts research and makes public statements regarding the use and 'safety' of MSG and associated products. See the website, The Glutamate Association. Okay, now you have access to both sides of the story.
Why enhance the flavor with MSG when you can enhance the flavor with herbs, garlic, onion, or cilantro and celery or pepper and curry? If you want to find out whether MSG is safe, instead of asking the FDA, ask the people who have MSG restaurant syndrome. Back in the 1950s, people called it Asian restaurant syndrome. If you want to find out what it feels like, check out the website, Chinese restaurant syndrome.
Any type of restaurant can add MSG to food if it wants to. Usually there are no signs up telling you MSG has been added to food or comes with the canned sauces put in the food. Some restaurants have signs saying "We don't add MSG to the food."
Other eateries will tell you they don't add the MSG to food already cooked, but the canned foods and sauces may have MSG. Sometimes soy sauce or oyster sauce may have MSG, but the food cooked in the restaurant don't have added MSG. The sauces have it because they come from another manufacturer outside the restaurant. So check carefully if MSG gives you an adverse or allergic reaction.
Chinese restaurant syndrome refers to a collection of symptoms that some people experience after eating Chinese food. A food additive called monosodium glutamate (MSG) has been implicated, but it has not been proved to be the substance that causes this condition. The names of MSG adverse reactions include, hot dog headache, glutamate-induced asthma, and MSG (monosodium glutamate) syndrome.
A few years ago one individual sitting across from me eating a soup that contained MSG, said she felt as if her cheek bones were protruding forward through her skin. This feeling of facial pressure is one of the typical symptoms of an adverse reaction to MSG in any given food. She didn't like the symptoms, which went away when she stopped eating fast food containing MSG to extend the flavor.
According to the Chinese restaurant syndrome article, "In 1968, reports of a series of reactions to Chinese food were first described. MSG was reported to cause these symptoms, but subsequent research produced conflicting data. Many studies were performed, but a majority failed to show a connection between MSG and the symptoms that some people describe after eating Chinese food.
For this reason, MSG continues to be used in some meals. However, it is possible that some people are particularly sensitive to food additives, and MSG is chemically similar to one of the brain's most important neurotransmitters, glutamate."
The Chinese Restaurant Syndrome article also noted the symptoms of MSG reactions. Note, that it's not just Asian restaurants that put MSG into food. It can be any restaurant in the nation that can put MSG in food if the restaurant wants to. The idea is to find out before you sit down in a restaurant whether MSG is in which foods.
Many times, club meetings take place in restaurants where the food is full of MSG. So check before your pay in advance when making a reservation if the food served has MSG and whether you get adverse reactions to it. Not everyone has adverse reactions. Do you? Also see the article, Hot Dog Headache - RightHealth.
Maybe you're getting tired of the MSG (monosodium glutamate) in some fast-food restaurants. You'll find MSG more in restaurants that serve Asian or Pacific Islands foods, but not always. So just ask the manager to ask the cook whether there is MSG in all foods, or some foods. MSG enhances flavor. But it may also make a few changes in your brain chemistry.
If you want to read about neurodegenerative symptoms, check out the study, Histological and biochemical effects of monosodium glutamate on on the frontal lobe of adult Wistar rats. Okay, rats shouldn't be eating food containing MSG, but what about people? There have been some human clinical trials.
Not every person feels any symptoms from MSG. That's why you have various clubs meeting in restaurants week after week for years without anyone complaining that most of the food contains MSG. So it's an individual response. Some people are sensitive to it, and some won't notice anything and keep on eating MSG in restaurants decade after decade.
No restaurant is losing money from adding MSG to food, and those restaurants who removed MSG from being added to foods usually have highly salted food instead, again with no loss in income. It's an individual choice, and you have the freedom to choose eating any food you want.
Restaurants who don't add MSG to food usually will advertise that they add no MSG to the food. But what about the canned sauces they use where the MSG is added to the cans of food or sauces before the restaurant opens the cans and serves the food covered in the various sauces?
Consider that can of food...Just ask the manager if he or she knows whether the ingredients on the label of a can of various types of soups, sauces, or canned vegetables or meats contains MSG.
Sometimes soy sauce contains a small percentage of MSG. If you ask to read the label on any given can of food the restaurant uses, chances are it won't be available. But you can try. Or you can just order a plate of food with nothing added.
Some meats are already seasoned in a package when they arrive from the factory frozen or in cans, jars, bottles, or other packaging. See, Is MSG hiding in your food? - monosodium glutamate - includes list. Also check out, 8 Foods That Trigger Headaches - Headache and Migraine Center.
The conclusion of that study, Histological and biochemical effects of monosodium glutamate on on the frontal lobe of adult Wistar rats noted the following information: "The side effects of its consumption on the frontal lobe have been shown from this study based on the biochemical and histological alterations observed. It has been shown that nerve cell degeneration and brain lesions result from MSG consumption.
"These changes might affect locomotion, reasoning, memory, language, and social and sexual behaviour. With these results, it is feasible that the functions of the frontal lobe as the organ for executive decision may be adversely affected. It is recommended that further research be carried out investigating the effects of MSG on specific areas of the frontal lobe (for instance, Broca’s speech area) and other parts of the brain."
Are you still ready to enhance or extend flavor with MSG? When any given restaurant enhances flavor in foods with MSG, it's to bring you back again to buy more food next time you eat there. So the goal in many cases is to make money for the restaurant, especially when competition is keen between restaurants.
There are quite a few Chinese restaurants in the USA that have put up signs or listed on their menus that they add no MSG to the food. Maybe they add no MSG, but what about all those canned sauces for example, packaged soy sauce or canned oyster sauce that come from manufacturers outside the restaurant that may have added MSG?
Even some canned soups have MSG. If you check the supermarket label, you'll notice a few popular soup brands have taken out the MSG they had in there a decade or more ago and substituted processed salt or sea salt.
Symptoms of adverse and/or allergic MSG reactions include the following, according to the Chinese restaurant syndrome article:
Numbness or burning in or around the mouth
Sense of facial pressure or swelling
Chinese restaurant syndrome is usually diagnosed based on the symptoms. The health care provider may ask the following questions as well: Have you eaten Chinese food within the past 2 hours? Have you eaten any other food that may contain monosodium glutamate within the past 2 hours?
The following signs may also be used to aid in diagnosis:
- Abnormal heart rhythm observed on an electrocardiogram
- Decreased air entry into the lungs
- Rapid heart rate
Treatment depends on the symptoms. Most, such as headache or flushing, need no treatment. Life-threatening symptoms require immediate medical attention. They may be similar to any other severe allergic reaction and include:
Shortness of breath
Swelling of the throat
Most people recover from mild cases of Chinese restaurant syndrome without treatment and with no lasting problems. People who have experienced life-threatening reactions need to be extremely cautious about what they eat and should always carry medication prescribed by their doctor for emergency treatment.
According to the Chinese Restaurant Syndrome article, "If you experience any symptoms such as shortness of breath, heart palpitations, chest pain, or swelling of the lips or throat, go to the nearest emergency room immediately."
What 10 food additives or shortenings used by some restaurants and eateries or sold by manufacturers to supply cafeterias, restaurants, and eateries are considered most toxic to your health and yet labeled as safe to put in food or use as shortening?
Possible Health Effects of Various Processed Food Additives
Why raise your risk of health problems? Many restaurants use vegetables, binders, fillers, or extenders to flesh out the volume of other foods. But basically, any food that has been canned, dehydrated, or had chemicals added to it is a processed food can be one of the toxic ingredients.
These additives make up about 60 percent of the average American diet. Here's a list of toxic foods to avoid. For more information, check out the article, "Processed Food Pitfalls: Top 10 Toxic Food Ingredients," by Jillian Michaels, creator of JillianMichaels.com, published at the Everyday Health site.
When you read the article, "Processed Food Pitfalls: Top 10 Toxic Food Ingredients," you'll see in detail what the various food ingredients mentioned may do to your body. Food mentioned include the hydrogenated oils/transfats, some artificial sweeteners, white flour, BHA, a preservative put in packaging, MSG, and certain artifical food colorings. So check out that article for explanations what those ingredients may do to your body.
Also mentioned in the top toxic food article are some products made with white flour such as pasta. You also can refer to my January 17, 2011 Examiner.com article on not always eating white rice, white bread, or white beans.
See, Don't eat white foods in the evening - Sacramento Nutrition Examiner. It's just that colorful red and black beans have more nutrition than white beans. But when it comes to bread, that whole wheat bread will raise your blood sugar just as much as the slice of white bread.
When it comes to transfats, there's a law in many cities telling restaurants to stop using trans fats. But some eateries still use food products that contain palm oil. To turn various tropical oils such as palm oil into trans fat, factories combine the palm oil with hydrogen to turn it into a solid transfat in order to lengthen any given product's shelf life.
Glutamate on your mind?
Do all of us at times need a brain cleaner that works something like a nature-made drain cleaner of sorts? As for brain cleaners, a recently developed method at the Weizmann Institute holds promise for treating brain injuries, according to the January 17, 2007 news release, "Brain cleaner."
When glutamate is released by damaged or dying brain cells, the result is a flood that overexcites nearby cells and kills them. For the general consumer, such as a senior citizen looking for more information on the role glutamate plays in brain activity, you also may be interested in taking a look at the site, "The role of glutamate in dementia."
A new method for ridding the brain of excess glutamate has been developed at the Weizmann Institute of Science. This method takes a completely new approach to the problem, compared with previous attempts based on drugs that must enter the brain to prevent the deleterious action of glutamate.
Many drugs, however, can't cross the blood-brain barrier into the brain, while other promising treatments have proved ineffective in clinical trials. Prof. Vivian Teichberg, of the Institute's Neurobiology Department, working together with Prof. Yoram Shapira and Dr. Alexander Zlotnik of the Soroka Medical Center and Ben Gurion University of the Negev, has shown that in rats, an enzyme in the blood can be activated to "mop up" toxic glutamate spills in the brain and prevent much of the damage. This method may soon be entering clinical trials to see if it can do the same for humans.
Though the brain has its own means of recycling glutamate, injury causes the system to malfunction, leading to glutamate build up
Professor Teichberg reasoned that this problem could be circumvented by passing glutamate from the fluid surrounding brain cells into the bloodstream. But first, he had to have a clear understanding of the mechanism for moving glutamate from the brain to the blood. Glutamate concentrations are several times higher in the blood than in the brain, and the body must be able to pump the chemical 'upstream.' Glutamate pumps, called transporters, are found on the outsides of blood vessels, on cells that come into contact with the brain. These collect glutamate, creating small zones of high concentration from which the glutamate can then be released into the bloodstream.
Basic chemistry told him that he could affect the transporter activity by tweaking glutamate levels in the blood. When blood levels are low, the greater difference in concentrations causes the brain to release more glutamate into the bloodstream.
He uses an enzyme called GOT that is normally present in blood to bind glutamate chemically and inactivate it, effectively lowering levels in the blood and kicking transporter activity into high gear, according to the January 17, 2007 news release, "Brain cleaner." In their experiments, Teichberg and his colleagues used this method to scavenge blood glutamate in rats with simulated traumatic brain injury. They found that glutamate cleared out of the animals' brains effectively, and damage was prevented.
Yeda, the technology transfer arm of the Weizmann Institute, now holds a patent for this method, and a new company based on this patent, called "Braintact Ltd.," has been set up in Kiryat Shmona in northern Israel and is currently operating within the framework of Meytav Technological Incubator. The US FDA has assured the company of a fast track to approval. If all goes well, Phase I clinical trials are planned for the near future.
The method could potentially be used to treat such acute brain insults as head traumas and stroke, and prevent brain and nerve damage from bacterial meningitis or nerve gas. It may also have an impact on chronic diseases such as glaucoma, amyotrophic lateral sclerosis (ALS) or HIV dementia.
"Our method may work where others have failed, because rather than temporarily blocking the glutamate's toxic action with drugs inside the brain, it clears the chemical away from the brain into the blood, where it can't do harm anymore," Teichberg explained, according to the news release.
An injury to the brain can be devastating. When brain cells die, whether from head trauma, stroke or disease, a substance called glutamate floods the surrounding areas, overloading the cells in its path and setting off a chain reaction that damages whole swathes of tissue.
Glutamate is always present in the brain, where it carries nerve impulses across the gaps between cells
When this chemical is released by damaged or dying brain cells, the result is a flood that overexcites nearby cells and kills them. Professor Vivian I. Teichberg's research is supported by the M.D. Moross Institute for Cancer Research; the Nella and Leon Benoziyo Center for Neurosciences; the Carl and Micaela Einhorn-Dominic Brain Research Institute; the Mario Negri Institute for Pharmacological Research – Weizmann Institute of Science Exchange Program; the Ruth and Samuel Rosenwasser Charitable Fund; the estate of Dr. Frank Goldstein, Chevy Chase, MD; Mr. and Mrs. Irwin Green, Boca Raton, FL; and the estate of Anne Kinston, UK.
What is Glutamate?
Glutamate is an amino acid, found in all protein-containing foods. Amino acids are the building blocks of proteins. This amino acid is one of the most abundant and important components of proteins. Glutamate is found naturally in protein-containing foods such as cheese, milk, mushrooms, meat, fish, and many vegetables. Glutamate is also produced by the human body and is vital for metabolism and brain function. Tomato juice has a large amount of glutamate.
A lot of foods have naturally-occurring glutamate. But monosodium glutamate, MSG, when added to food as a flavor extender becomes a neurotoxin. Monosodium glutamate (MSG) has been shown to penetrate placental barrier and distribute almost evenly among embryonic tissues using 3H-Glu as a tracer, explains a study, "Transplacental neurotoxic effects of monosodium glutamate on specific brain areas of filial mice."
Monosodium glutamate, or MSG, is the sodium salt of glutamate. When MSG is added to foods, it provides a similar flavoring function as the glutamate that occurs naturally in food. MSG is comprised of nothing more than water, sodium and glutamate.
Glutamate is actually 10 times more abundant in human breast milk than in cow's milk. Glutamate-containing food ingredients, such as hydrolyzed protein and autolyzed yeast extract, also must be listed on food labels. When glutamate is a component of natural protein foods, like tomatoes, it is not listed separately on the label.
Too many cooks at home or in eateries may try to wake up tired food by adding MSG
Monosodium glutamate (MSG) is mistakenly used as a taste enhancer on usually overcooked or 'tired' foods that don't have left enough flavor because they've been stored a long time. Up to 40 percent of the USA population is allergic to MSG. See the articles, studies, and bibliography for reference on adverse reactions related to MSG in food at the Truth in Labeling site. Also see the article, "Monosodium Glutamate: Poison the Body to Better the Taste," at the World Wide Health Center Net site.
According to the Truth in Labeling site, "On March 13, 2009, President Obama stated, in part, that the nation’s decades-old food safety system is a 'hazard to public health.' While nominating Margaret Hamburg, M.D., the former New York Health Commissioner, for the position of FDA commissioner, he also indicated that he would be creating a Food Safety Working Group to coordinate food safety laws throughout government and to advise him on how to update them."
There are healthier, natural alternatives to MSG: Lemon, orange, cherry, or lime juice would be a better flavor enhancer
Even cooking with a small amount of organic wine (without added sulfites) is safer. MSG secretly addicts the consumer to the food by tricking the brain into thinking the food is more flavorful as it hits the taste buds on the tongue. The hidden goal is to make sure the consumer will return to the product or restaurant and order the same food again.
Instead of MSG, as a flavor enhancer, use natural, fresh food flavors, stock, or add a small amount of healthier spices, vegetables, or fruit juices without overpowering the aroma and flavor of the food. MSG is dangerous to the central nervous system. A long list of books have been written about its neurotoxicity. For your reference, a bibliography of 62 studies on the toxicity of MSG are listed at the bottom of the article, "This is What the Data Say About Monosodium Glutamate Toxicity and Human Adverse Reactions," compiled by Adrienne Samuels, Ph.D. May 2009.
You'll find MSG in salad dressings, a variety of restaurant foods, in several types of canned soups and vegetables, in various types of prepared fish or meat products, and in some bottled or canned savory sauces. Read the label before you buy the product because it's often hidden in foods you'd never think would contain MSG.
Why is MSG still listed at safe by the FDA? Will the Department of Agriculture and the FDA ever share information and connect, commit, and communicate better regarding what additives are being put in most foods? Related research is abundant.
When older adults have a vitamin D deficiency
Older individuals who are vitamin D deficient also tend to have compromised immune function, according to new research accepted for publication in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism. The study, "Vitamin D Deficiency is Associated with Inflammation in Older Irish Adults," is now published online, ahead of print in the The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM).
Vitamin D deficiency may compromise immune function. Vitamin-deficient seniors are more likely to have biomarkers for heart disease and inflammation says a new study. Older individuals who are vitamin D deficient also tend to have compromised immune function, according to the new research.
Vitamin D plays an important role in helping the body absorb calcium needed for healthy bones
The skin naturally produces vitamin D when it is exposed to sunlight. People also obtain smaller amounts of the vitamin through foods, such as milk fortified with vitamin D. More than 1 billion people worldwide are estimated to have deficient levels of vitamin D due to limited sunshine exposure.
"Our data suggest vitamin D may be involved in maintaining the health of the immune system as well as the skeletal system," said one of the study's authors, Mary Ward, PhD, of the University of Ulster in Coleraine, U.K, according to the February 25, 2014 news release, Vitamin D deficiency may compromise immune function. "This study is the first to find a connection between vitamin D levels and inflammation in a large sample of older individuals." The observational study of 957 Irish adults who were at least 60 years old examined vitamin D levels as well as biomarkers of inflammation.
Participants who were vitamin D deficient were more likely to have high levels of these biomarkers, which are linked to cardiovascular disease and inflammatory conditions such as multiple sclerosis and rheumatoid arthritis
"The results indicate immune function may be compromised in older individuals with vitamin D deficiency," Ward said in the news release. "Ensuring older individuals have optimal vitamin D levels may be a way to boost immune function in this population, but this needs to be confirmed through additional studies."
Other authors of the study include: E. Laird and A.M. Molloy of Trinity College in Dublin, Ireland; H. McNulty, L. Hoey, E. McSorley, J.M.W. Wallace, E. Carson and J.J. Strain of the University of Ulster; and M. Healy, M. Casey and C. Cunningham of St. James's Hospital in Dublin.
Founded in 1916, the Endocrine Society is the world's oldest, largest and most active organization devoted to research on hormones and the clinical practice of endocrinology. Today, the Endocrine Society's membership consists of over 17,000 scientists, physicians, educators, nurses and students in more than 100 countries. Society members represent all basic, applied and clinical interests in endocrinology. The The Endocrine Society is based in Washington, DC. You also can follow the Endocrine Society on Twitter.
How increased brain cell activity boosts brain fluid levels of a protein linked to Alzheimer's disease
Increased brain cell activity boosts brain fluid levels of a protein linked to Alzheimer’s disease, according to new research in another study from scientists at Washington University School of Medicine in St. Louis. The study, "Neuronal activity regulates extracellular tau in vivo," is published online since February 18, 2014 in the Journal of Experimental Medicine. Tau protein is the main component of neurofibrillary tangles, one of the hallmarks of Alzheimer’s disease. It has been linked to other neurodegenerative disorders, including frontotemporal dementia, supranuclear palsy and corticobasal degeneration.
“Healthy brain cells normally release tau into the cerebrospinal fluid and the interstitial fluid that surrounds them, but this is the first time we’ve linked that release in living animals to brain cell activity,” said senior author David M. Holtzman, MD, according to the February 25, 2014 news release, Brain cell activity regulates Alzheimer’s protein . “Understanding this link should help advance our efforts to treat Alzheimer’s and other neurodegenerative disorders associated with the tau protein.
Tau protein stabilizes microtubules, which are long columns that transport supplies from the center of the cell to the distant ends of the cell’s branches
Some tau in the cell is not bound to microtubules. This tau can become altered and clump together inside brain cells, forming structures called tangles. Scientists have tracked the spread of these clumps through brain networks in animal models.
“In Alzheimer’s disease, you first see clumps of tau in a region called the entorhinal cortex, and then in the hippocampus, and it continues to spread through the brain in a regular pattern,” said Holtzman, the Andrew B. and Gretchen P. Jones Professor and head of the Department of Neurology, according to the news release. “In another disorder, supranuclear palsy, tau clumps first appear in the brain stem and then spread to regions that the brain stem projects to.”
These regular patterns of tau spread through brain networks have led scientists to speculate that dysfunctional tau travels to different brain regions via synapses — the areas where individual nerve cells communicate with each other.
Holtzman’s results support this hypothesis, showing that when nerve cells “talk” to each other, tau levels go up in the fluids between those cells, suggesting that brain cells are secreting tau when they send signals. So far, the researchers only have been able to measure single copies of tau in brain fluid, not the tau clumps. They are looking for a way to detect the clumps.
If brain cells can secrete and take in clumps of tau, the scientists believe, these clumps may cause previously normal tau in the receiving cell to become corrupted, fostering the spread of a form of tau involved in disease. “We also want to know whether brain cells are secreting tau as waste or if tau has a function to perform outside the cell,” Holtzman said in the news release. “For example, there have been hints that tau may modulate how easy or difficult it is to get brain cells to communicate with each other.”
The Tau Consortium and the Japan Society for the Promotion of Science supported the study. Authors are Yamada K, Holth JK, Liao F, Stewart FR, Mahan TE, Jiang H, Cirrito JR, Patel TK, Hochgräfe K, Mandelkow E-M, and David M. Holtzman. You can check out the abstract of the study online, "DM. Neuronal activity regulates extracellular tau in vivo," published online February. 18, 2014 in the Journal of Experimental Medicine.
Tau is primarily a cytoplasmic protein that stabilizes microtubules, according to the study's abstract
What happens is that tau also is found in the extracellular space of the brain at appreciable concentrations. Researchers are trying to understand more about tau. Although its presence there may be relevant to the intercellular spread of tau pathology, the cellular mechanisms regulating tau release into the extracellular space are not well understood. That's why the research focused on testing the context of neuronal networks.
To test this in the context of neuronal networks in vivo, the researchers used in vivo microdialysis. Increasing neuronal activity rapidly increased the steady-state levels of extracellular tau in vivo.
How does glutamate play a role?
Importantly, the researchers write in the study's abstract, presynaptic glutamate release is sufficient to drive tau release. Although tau release occurred within hours in response to neuronal activity, the elimination rate of tau from the extracellular compartment and the brain is slow (half-life of ~11 d). The in vivo results provide one mechanism underlying neuronal tau release and may link trans-synaptic spread of tau pathology with synaptic activity itself.
Glutamate is an excitatory neurotransmitter, but may also act as an endogenous neurotoxin, notes that study's abstract. There is good evidence for an involvement of the glutamatergic system in the pathophysiology of dementia.
The glutamatergic transmission machinery is quite complex and provides a gallery of possible drug targets. There are good arguments both for an agonist and an antagonist strategy. When following the antagonist strategy, the goal is to provide neuroprotective effects via glutamate receptor antagonisms without inhibiting the physiological transmission that is required for learning and memory formation.
The study's abstract explains that when following the agonist strategy, the goal is to activate glutamatergic transmission without neurotoxic side effects. Several available antidementia drugs may modulate the glutamatergic transmission. Fascinating topic how glutamate works in the brain. You may wish to check out the site, "Everything You Need To Know About Glutamate And Monosodium Glutamate."
You also may wish to check out the book, Middleton's Allergy: Principles and Practice, and take a look at the section, "Adverse reactions to food and drug additives."Authors are Bush RK, Taylor SL, Hefle SL. Adkinson NF Jr., Yunginger JW, Busse WW, Bochner BS, and Holgate ST, eds. 6th ed. Philadelphia, Pa; Mosby Elsevier; 2003: chap 90. Or just to have around the house as a reference, you may wish to see the article, "Food poisoning." It's published in the journal Emergency Medicine Clinics of North America. 2007:357-373. Authors are Lawrence DT. Dobmeier SG, Bechtel LK, Holstege CP.