Talk:Excitotoxicity

Concern

This page appears to be part of a network of pages being edited to promote positions held in homeopathic and alternative medicine and contrary to the current scientific consensus. Specifically, it attempts to imply MSG is a toxic substance through pointed discussion of glutamate. These edits are possibly being made to push the views of Dr. Russell Blaylock specifically, however it may just be because these positions are quite prevalent in alternative medicine circles. This includes the pages on 2009 flu pandemic vaccine, Water_fluoridation_controversy, Dental amalgam controversy, and Aspartame.— Preceding unsigned comment added by 24.206.70.55 (talk • contribs) 1 January 2016 (UTC)

No, excitotoxicity is a very real disorder and there exists a scientific consensus within the field of neuroscience as to it’s existence; it is a common form of neurotoxicity. Just because some homeopaths and alt. Med. practitioners pseudoscientifically claim their patients are suffering excitotoxicity because of X is in their body or missing from their body does not change this. As an example: Alt med people often misdiagnose people with candidiasis with bogus tests, but this does not mean there is no such thing as the medical condition called thrush caused by a Candida infection.--Literaturegeek | T@1k? 01:20, 1 November 2018 (UTC)

MSG

I don't know very much about this subject, so I apologize for any inaccuracies. I removed statements about the toxicity of MSG which lack mainstream scientific support, and which are adequately covered in that article. Molybdenumblue 14:12, 14 Apr 2005 (UTC)

'to lack mainstream scientific support" : why only circumstantial evidence is possible.

ADHD Not to eat E621 / msg is now also followed by adhd and add people everywhere at internetfora they are saying that if you (genetically) have adhd, you better not eat too much E621 but it is only statistically that people feel a bit better. You cannot see it live in action unfortunately. — Preceding unsigned comment added by 87.212.168.115 (talk) 12:00, 14 September 2012 (UTC)

Agree. Just because most people don't suffer issues from excitotoxicity, doesn't mean it doesn't exist. Most people don't suffer e.g. gluten intolerance, but celiac and non-celiac gluten intolerance are recognised medical conditions, as is diabetes. In these cases, a normal food acts as a poison, and Wikipedia serves the public by explaining how. Why should it not do so here? I would suggest readers consider the possibility that the food industry recognises that it loses billions of dollars each year because people are afraid of MSG in food, and so it tends to promote information saying MSG is safe (which it may well be, up to a point) and stifle debate about whether it isn't. To avoid risk of committing the traitorous critic fallacy, I would ask we all stay in healthy debate. -- Mike Amy

The lack of scientific peer review and wide research here is a concern. This article seems to be dominated by the research of a single individual (Russell Blaylock) whose work on various topics such as aspartame and immunisation remains highly controversial, and whose own entry in Wikipedia reflects this. Glutamates occur naturally in a wide variety of foods. The claims in this article seem in direct contradiction to the main body of the Wikipedia articles on glutamate flavoring and glutamic acid and should not therefore be presented as undisputed fact. The article seems to breach Wikipedia's NPOV standard. — Preceding unsigned comment added by Walkerdage (talk • contribs) 04:48, 27 January 2014 (UTC)

Dr Blaylock is like Dr Oz, a popularizer of medical and biochemical science. If you doubt what Blaylock says about MSG, read some of the citations in this article and in his book. A Google Scholar search on "glutamate excitotoxicity" yielded more than 26,000 hits. Excitotoxity is mainstream science. Greensburger (talk) 08:16, 8 February 2014 (UTC)

And there are over 21,000 hits for "aliens on mars" on Google scholar. That doesn't mean there's a scientific consensus that aliens exist on mars... 128.40.76.3 (talk) 18:57, 14 April 2014 (UTC)

Note that the amount of research on the highly popular topic of existence of life on the closest planet to Earth bears no significance whatsoever on the topic of human brain chemistry. Red herring fallacy. -- Mike Amy

Well, if Dr Blaylock is like Dr Oz then I suppose this article must be of high quality. 70.186.199.13 (talk) — Preceding undated comment added 20:06, 21 October 2014 (UTC)

Note that any attacks on Dr. Blaylock are using the Argument Ad Hominem fallacy, attacking a person instead of the idea. Whether or not Dr. Blaylock is untrustworthy has increasingly diminished significance with each piece of work done by other researchers. If there are more than 20,000 pieces of work, then his overall impact approaches zero. Given the extensive research by other scientists, a stronger argument based on this fallacy would be that all English-speaking scientists told lies as children, and as most of the referenced research is in English, we shouldn't trust it. -- Mike Amy

Food Additives

I removed the material related to the possible role of some food additives as neurotoxins. First, because it was copied directly from an article in a copyrighted journal. Second, because this wikipedia article is about the specific neurobiological process of excitotoxicity, not about neurotoxins (not all the toxins mentioned in the journal article are believed to work via excitotoxicity). If the editor wishes to expand on this material I would suggest starting a new article on that topic. Nrets 15:29, 12 December 2005 (UTC)

I corrected the misleading statement regarding concentrations of aspartate in the blood in the "Excitotoxins in food additives" section. The original source cited was discussing bioequivalence of capsule versus solution ingestion of aspartame. It was not a study on the levels of aspartate in the blood after the consumption of aspartame, as was implied in the para. The same authors of that source (Stegink, et al) have several studies showing no significant effect of aspartame consumption on aspartate concentrations in the blood. Dutchroll (talk) 01:19, 25 August 2008 (UTC)

Made more NPOV since there is a disagreement in the scientific community. One reference that discussed bioequivalence did have a study of people ingesting aspartame and showed a large aspartate spike. One reference showed only a small rise in aspartate. Balanced statement about Blood Brain Barrier (BBB) with statement about parts of brain unprotected by BBB -- an issue raised in scientific journal articles. Included reference to Science journal article on split opinion of neuroscientists on this issue. Twoggle (talk) 03:42, 12 September 2008 (UTC)

List of excitotoxins

I know the Aspartic Acid in aspartame is an excitotoxin. Shouldn't there be some sort of list of known excitotoxins on this page? Or is that on a different page? jess523s 00:43, 1 January 2006 (PST)

Maybe a cursory list would be appropriate, but the focus of the article should be on the process of excitotoxicity. In my opinion, for a comprehensive list of excitotoxins (and mechanisms of action) might be better suited for a separate article. Nrets 18:22, 1 January 2006 (UTC)

(18 years later) Yes, there should be some sort of list of known excitotoxins on this page. 76.190.213.189 (talk) 19:07, 4 February 2024 (UTC)

Controversies?

I would find it helpful if someone familiar with the field could identify current controversies surrounding excitotoxicity (e.g., is the cause of Delayed Calcium Deregulation still controversial, or has that been figured out?). Can anyone list some of these controversies? Or help me figure out where I can find out? Thanks much, delldot | talk 21:19, 21 March 2006 (UTC)

Source specificity

Should the source specificity controversy be addressed? It was sparked by papers in the early 90's by Tymianski et al. that showed that calcium influx through NMDARs, not calcium load itself, was what was harmful to the cell. Since then molecules linking nmdars to mediators of excitotoxicity such as nNOS have been found. I think it's interesting because it conflicts with the traditionally widely held belief that calcium load alone is what's harmful to the cell. But is this too obscure? Thanks, delldot | talk 20:00, 7 May 2006 (UTC)

Major edit

I've just finished a large edit, converting refs to the current <ref> style, mostly. I hope this is ok with everyone. I don't expect anyone will have any problems with it, but if you do, let me know. delldot | talk 06:25, 31 January 2007 (UTC)

Food additives

I'm a little concerned about the food aditive section. I think that this is a fairly marginal view. I don't believe that it is commonly accepted that excitotoxicity is involved in autism, though I admit I don't know. All of the stuff I find sketchy is from this one guy, Blaylock and his website DORway.com.

The argument that food additives such as MSG and aspartame are dangerous seems based around the idea that they can raise your blood plasma level of those amino acids in this article. But as I understand it, amino acids don't usually cross the blood brain barrier, so this doesn't produce a neurotoxic threat. These amino acids already exist in the bloodstream in much higher concentrations than the brain could handle; thus when the BBB is breached, e.g. in head trauma, this has been thought to be a possible contributing factor to the glutamate rise found in that condition. So anyway, I feel like this info might be misleading. I'd like to add content to the article about how amino acids don't cross the bbb and how increased blood plasma level of these amino acids is not necessarily harmful. I have some sources (e.g. Tsuchioka T, Fujiwara T, and Sunagawa M. Effects of glutamic acid and taurine on total parenteral nutrition. Journal of Pediatric Surgery. 2006 Sep;41(9):1566-1572. PMID 16952593. Retrieved on January 31, 2007) and will find others. I just wanted to put a note here so I could work with the other folks who maybe originally put this info in or have the opposite POV. I'm going to go ahead and add the info in when I have it all, but if there's any problem we can discuss it here. I'd also like to discuss removing the category:food safety, since I think it's at best tangentially related, and it's controversial (since you can't qualify something's membership in a category the way you can in a list, it has to be obvious and noncontroversial). Let me know if you want to discuss this further. Thanks, delldot | talk 17:21, 31 January 2007 (UTC)

The belief that excitotoxins can't cross the blood-brain barrier is the official position by the "scientific establishment" and the government regulatory agencies that have declared aspartame and msg safe. However, there are quite a lot of studies that are hard to explain without assuming BBB-leaks. Look at the references I mentioned in the section below for a more nuanced view. MaxPont 08:02, 24 July 2007 (UTC)

I have removed the following unsourced nonsense regarding soy protein excitotoxicity:

"Soy proteins are also increasingly suspected of being excitotoxins as more evidence makes clearer their effect on the body's hormones. This has been studied with rats. Soy lecithin is likely the worst of all the soy proteins."

First of all, I can find no reliable sources to back the claim that soy is excitotoxic, although Dr. Russell Blaylock seems to be leading the specious crusade against hydrolyzed soy protein isolate without letting that pesky fact get in his way! It's possible he mentions some sources to back his claims in his reports...but these extremist, self-published documents are only available to paying subscribers. Second, not even Dr. Blaylock claims that soy excitotoxicity would be related to hormonal alterations. Finally, soy lecithin is not a protein at all, but rather a collection of lipids, some of which actually exhibit neuroprotective effects (see Aabdallah DM, Eid NI. "Possible neuroprotective effects of lecithin and alpha-tocopherol alone or in combination against ischemia/reperfusion insult in rat brain." J Biochem Mol Toxicol. 2004;18(5):273-8. PMID 15549708). I would be very interested to see any good evidence supporting the original claims, so by all means, let me know if some exists. St3vo (talk) 20:35, 18 January 2008 (UTC)

I have no personal position on the above topic, however I believe there are several misunderstandings in the points made in the main excitotoxin topic page and in the talk items above:

- The concerns about so-called "excitotoxins" is predominantly in regard to their impact on the hypothalamus, which is not behind the blood brain barrier. Dr. Blaylock is very clear about this in his argument. - I have not seen any claims that soy itself is excitotoxic, however my understanding is that the manufacturing process for protein isolates (whey being the primary example) create unbound glutamic acid and aspartic acid which are the primary offenders if one believes that these are toxic - The presence of glutamtes as part of the normal cellular signaling mechanism does not counter the argument that unnaturally high amounts of these in the bloodstream could be harmful, as is implied above.

The increasing popularity of Whey-based nutritional supplements means that many people are now consuming so-called excitotoxins in amounts much larger than those found in food additives. Hopefully someone who fully understands both sides of the argument and who can shed light on whether there is theoretical or demonstrated risk to proper hormone function can update the main page with specifics. — Preceding unsigned comment added by Vincentjr12 (talk • contribs) 03:35, 31 August 2012 (UTC)

Why?

What evolutionary/physiological advantage would there be to have a neurotransmitter itself be a degenerative substance? It surely must be possible to have another neurotransmitter in its place (or deactivate the signal-trandsuction pathways which cause apoptosis). Correct me if I'm mistaken, but this makes no sense to me. - 2-16 15:10, 30 May 2007 (UTC)

This academic article could add insight here. If anyone can access the article it would be helpful to integrate the findings in the WP article:

REVIEW ARTICLE The role of excitotoxicity in neurodegeneration

Folia Neuropathol 2005; 43 (4): 322-339

authors: Elżbieta Salińska, Wojciech Danysz, Jerzy W. Łazarewicz,

Abstract:

A body of evidence suggests that the mechanisms of excitotoxic neuronal damage evoked by excessive or prolonged activation of the excitatory amino acid receptors may be involved in pathogenesis of brain damage in acute insults and in chronic neurodegenerative diseases. In this review we briefly discuss several selected mechanisms of the excitotoxicity, focusing attention on the role of ionotropic glutamate receptors, calcium transients and calcium-mediated cell injury. In the second part of this paper we provide information on elements of excitotoxicity in brain diseases.

keywords: calcium, excitatory amino acid receptors, neurodegeneration, NO, oxidative stress MaxPont 10:19, 23 June 2007 (UTC)

Here is the article: [1] MaxPont 10:32, 23 June 2007 (UTC)

Other references can be found from NIDAs Glutamate Cascade conference [2] [3]. A bit old but still useful.

Glutamate and the processes that lead to excitotoxicity are involved in a very important "learning" process, the "long term potentiation". Neurons respond to more input in a way that they become either more or less sensitive to incoming signals. By doing so the neural net is adjusted. That this process can also lead to cell death when it is disregulated due to pathological events has no evolutionary or physiological benefits. But in the healthy brain there should be no cells dying because of excitotoxicity. —Preceding unsigned comment added by 89.59.65.31 (talk) 14:09, 9 September 2007 (UTC)

Finding that could be integrated in the article

From Science Daily "Scientists Solve Structure of NMDA Receptor Unit That Could Be Drug Target for Neurological Diseases" [4] MaxPont (talk) 15:40, 15 November 2009 (UTC)

Food additives

From the history, I note that this section has been controversial. And for good reason. The references are old, primary (or news), and represent, with few exceptions, the view of a single researcher whose methods and views have been challenged by others. The sentence about division amongst neuroscientists is particularly interesting, since the news article cited describes a meeting of a "Social Issues Committee"...excellent evidence that this issue is less about medicine than social concerns. I'm removing the section as a bit too fringe for this article. Should others deem a brief statement necessary, it will require support from sources acceptable for medical claims, i.e. reviews in reliable journals. Keepcalmandcarryon (talk) 21:35, 15 November 2009 (UTC)

Link with spreading depression

The link with spreading depression, a chain reaction in the brain of potassium and glutamate release, is missing in the article. So is the role of extracellular potassium. I'll try and include it once I have the time. 2001:610:1908:C000:2C12:4A95:1844:BA52 (talk) 08:49, 13 November 2013 (UTC)

Normal Variation Is Not a Medical Problem.

Header sez it all.

I arrive here in the course of researching a commercial supplement promotor named Dr. Blaylock. Excitotoxins make up a large part of his promotions.

Most, but emphatically not all, of what the guy teaches is true -- but you don't need to pay for it: just read the Internet carefully.

Some of what he says is dangerous: he confuses the dangerous metals lead and mercury with all chemicals of which they may be a part. What he says about flu vaccines is incorrect and dangerous to the public. I believe that it is only possible for a dishonest person to say the things that his spokesman says in promoting his for-pay supplement promotion pamphlet, portentously titled "The Blaylock Report."

There is no doubt that at a sufficiently high dose everything, including water, is poisonous or otherwise harmful. What his spokesman says about aspertame(tm.) is unproven, if not aggressively dishonest and the result of hysterical promotion by ignorant cults.

DavidLJ (talk) 08:00, 27 June 2014 (UTC)

Very close to a certain paper

hello, this article is possibly based on this paper (Shaikh S, Dubey R, Joshi YM and Kadam VJ: Excitotoxicity and Cell Damage - A Review. In: Int J Pharm Sci Res 2013; 4(6); 2062-2066. doi:10.13040/IJPSR.0975-8232.4(6).2062-66) or written by the same authors, cheers, --Ghilt (talk) 07:58, 2 April 2016 (UTC)

AMPA and NMDA are not endogenous neurotransmitters

The first sentence of this article states 'In excitotoxicity, nerve cells suffer damage or death when the levels of otherwise necessary and safe neurotransmitters such as glutamate, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), or N-methyl-D-aspartic acid (NMDA) become pathologically high resulting in excessive stimulation of receptors'...this reads as though AMPA and NMDA are 'necessary and safe neurotransmitters'. The mentioning of AMPA and NMDA should either be removed, or the sentence re-phrased. — Preceding unsigned comment added by Mdx92129 (talk • contribs) 15:00, 9 January 2022 (UTC)

Food additives / monosodium glutamate

In an effort to make this article more properly encyclopedic, shouldn't it mention food additives (notably monosodium glutamate), if only briefly? The current version of this article doesn't mention either in the text of the article. That does a disservice to our readers and undermines our claim to treat subjects in an encyclopedic manner. 76.190.213.189 (talk) 19:09, 4 February 2024 (UTC)