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Carbonic Anhydrase Is A Key Driver Of Aging; Inhibiting It Is Beneficial

Discussion in 'Scientific Studies' started by haidut, Nov 18, 2016.

  1. haidut

    haidut Member

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    In support of Ray's views of CO2 as one of the main factors in mitochondrial biogenesis and health, and as such in a host of health conditions, this study found that carbonic anhydrase levels are higher and the enzyme itself is more active in both aging and degenerative conditions. Inhibiting the enzyme increased lifespan in an animal model and reversed the degenerative changes in the brain. This immediately brings up the role of thiamine and biotin as carbonic anhydrase inhibitors, and their beneficial effects in a host of conditions.
    Thiamine Is A Carbonic Anhydrase Inhibitor As Effective As Acetazolamide
    Thiamine Normalizes Pyruvate / Lactate Levels In Rats With Cancer
    Deficiency Of Vitamin B1 (thiamine) Can Cause The Cancer Metabolism
    Biotin As A Treatment For Multiple Sclerosis (MS)

    I would like to hear @tyw opinion on this as in another thread he mentioned a few scientists like Gilbert Ling not being very fond of the idea of CO2 as necessarily being a therapeutic target for either health or longevity. I think Ling specifically expressed doubt about the role of CO2 as an EWG similar to ATP or calcium.

    Mitochondrial proteomic profiling reveals increased carbonic anhydrase II in aging and neurodegeneration. - PubMed - NCBI
    "...Carbonic anhydrase inhibitors are used to treat glaucoma and cancers. Carbonic anhydrases perform a crucial role in the conversion of carbon dioxide and water into bicarbonate and protons.

    http://medicalxpress.com/news/2016-10-cell-protein-effects-aging.html

    "...Using a specialist process called 2D gel electrophoresis, the scientists separated out all the proteins found within the mitochondria of brain cells and muscle cells from normal young brains and normal middle-aged brains and compared the two samples. They found that the carbonic anhydrase was found in greater quantity and was more active in the samples of the middle-aged brain. Significantly, this increase was also reflected in samples from young brains suffering from early degeneration, suggesting that the increase is detrimental. To establish whether this was indeed detrimental and not evidence of the body's attempt to guard against this degeneration—known as a protective effect—the scientists studied the effect of carbonic anhydrase on nematode worms. They found that feeding carbonic anhydrase to the tiny c elegans worms—measuring around just one millimetre in length—reduced their life span."
     
  2. tyw

    tyw Member

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    Preface

    First, CO2 is used by the body in very significant ways. I fully support all high level benefits of CO2.

    At cell and below-cell level, you are correct that my reference was to Gilbert Ling. Ling's comments are that "CO2 as a significant EWC", is a statement that we cannot be sure of yet. ATP is the most significant EWC by far.

    It is important to note that CO2 from metabolism is produced in the Krebs cycle, and CO2 is made within the mitochondria itself. This CO2 then needs to make its way out of the mitochondria, out of the cell, and hopefully into serum, before it exerts any of the significant higher level effects.

    ----
    Mechanism

    From an observational point of view, it is clear that Carbonic Anhydrase does significant things in the body.

    The first thing that we should recognise from this fact, is that carbonic anhydrase catalyses a naturally occurring reaction, and simply speeds it up many fold in order to shuttle between the various related forms of CO2 (be it CO2 in gaseous form, or H2CO3 / carbonic acid, or HCO3- / bicarbonate). All these forms have different effects in the body.

    Also note the reactions of carbonic anhydrase:

    Image from Wikipedia:

    upload_2016-11-19_7-45-34.png (when CO2 is high, eg: tissues)
    upload_2016-11-19_8-22-44.png (when CO2 is low, eg: lungs and kidney)​

    For this discussion, we are primarily concerned with the first equation, and tissue levels of CO2 and H2CO3

    ----
    What causes what?

    With that in mind, we must get the arrow of causality correct in discussions of Carbonic Anhydrase activity.

    To frame this discussion, I will use the fact that during ageing, more Carbonic Anhydrase activity is present. It is then our job to ask: "Why would the body want to up-regulate carbonic anhydrase activity in tissues?".

    We assume that ageing causes some generically bad stuff to happen, and that carbonic anhydrase up-regulation is the precautionary response to that bad stuff. This response is likely meant to prevent further damage, and not necessarily to maintain optimal function.

    It is then logical to assume that if we correct the bad stuff at the root of the problem, then this precautionary measure to up-regulate Carbonic Anhydrase is no longer needed.

    Therein also lies my concern: If up-regulating Carbonic Anhydrase is an endogenous response to some bad stuff, then forcing its activity down does not necessarily fix that bad stuff, and may have negative consequences in the long term, despite short term benefits.

    It should also be noted that sometimes the fixing of things in the short term, is exactly what is needed for the body to get out of "panic mode" long enough for recovery to occur.

    These distinctions are important to distinguish, since they will inform us as to whether Carbonic Anhydrase inhibition is to be used Chronically, or should only be used as an Acute solution to obvious problems.

    In any case, this is obviously a stupidly complicated balancing act -- http://erj.ersjournals.com/content/erj/12/6/1242.full.pdf

    -----
    Thiamine not comparable to Man-made Carbonic Anhydrase Inhibitors

    Thiamine happens to "inhibit" carbonic anhydrase, but it also does so many other things up- and down-stream of carbonic anhydrase and CO2 related reactions.

    I write "inhibit" in parentheses, because the accurate statement is "the activity of Carbonic Anhydrase isozyme 2 (CA-2) is greatly reduced in the presence of Thiamine". In other words, we do not know if Thiamine "actively blocks" CA-2, or if it simply "provides the conditions to which CA-2 is no longer required".

    From the discussion in the last section, I am biased to say that the latter is the case, whereby Thiamine fixes the "generic bad stuff" that causes cells to react with increased Carbonic Anhydrase activity, and thus lets those cells relax into not expressing the CA-2 (and related) enzymes as much.

    This is likely different from the direct Sulfoamide inhibition mechanism that man-made carbonic anhydrase drugs rely on.

    As such, when discussing Thiamine, it is my opinion that we should not focus on the "carbonic anhydrase inhibition", as much as we do on the other more significant effects.

    ----
    CO2 as regulator of O2, and thus "giving permission" for metabolism proceed

    This is my current best guess at what CO2 does. I highly doubt that it is a significant enough EWC. This takes away the role of CO2 in very-low-level energy production. It doesn't interact well with charge-separated water either, so again, I do not think it has a direct energy conducting role.

    What it will do is regulate the amount of O2 that comes into the cell, as well as regulating pH to control eagerness of a cell to engage in metabolism.

    The high level effects, such as the Bohr effect, Lung CO2 exchange, and Kidney CO2-related exchange are all well studied. CO2 will encourage both oxygen uptake (eg: more breathing), and will facilitate oxygen delivery to tissues (bohr effect). All of these are regulatory mechanisms that favour particular levels of CO2 depending on the metabolic needs of a cell.

    Therefore, I do not believe in "more CO2 is better", just like I do not believe that "more energy is better". If you need to exercise, then yes, more CO2 retention means more oxygen delivery to the cells that need to produce more energy to deal with the demands of exercise. That says nothing about whether Exercise is good or bad, which requires a completely separate discussion.

    Similarly, we can talk about how particular breathing techniques allow for more CO2, but it is a leap of faith to say that it is CO2 that does all the things that good breathing will allow -- like improved sympathetic tone, which is so complected with the vagus nerve and the rest of the nervous system (and all the associated tissues and voltage gate calcium channels and what not) and fascial system (dependent on collagen hydration), that all we can confidently say is that "Good breathing techniques are good".

    Again, I am biased to believe that the up-regulation of CA-2 seen through ageing is a compensatory safety mechanism to push CO2 out of the mitochondria and possibly out of the cell, by allowing CO2 to be transported out via the "fast diffusing form" which is H2CO3.

    Now, what this does is still up to speculation ... for example, it could plausibly reduce the pH gradient between the mitochondrial matrix and cell cytosol, which in turn reduces delta psi, oxidative potential, shuts down insulin signalling, and allows for RET and Complex 1. As far as I am concerned, I have no clue whatsoever.

    ----

    Therefore, I believe in fixing the underlying conditions. One of the manifestations of compromised function is increase in Carbonic Anhydrase activity. Forcing action in a higher level regulatory mechanism puts the body out of balance.

    Sometimes, forcing a response is good -- adjusting to high altitude over a course of only a couple days. But we do not know enough about what this entire system is doing, to confident say that we can ensure balance by affecting this one enzyme.

    I should also remind readers that CA-2 is just one of the many carbonic anhydrases out there, and the others have significant impacts in different tissues. It is clear that the CO2-to-H2CO3 balance is strictly regulated at all hierarchies in the cell, for the body to dedicate so many different forms of the enzyme to regulate these compounds. Trying to say whether CO2 is good or bad is not the right question to ask. The question is how to determine and ensure the appropriate balance in the appropriate tissues at the appropriate times under the appropriate conditions.

    Substances like Thiamine work on underlying conditions, and are not comparable to direct Carbonic Anhydrase inhibitors.

    .....
     
  3. OP
    haidut

    haidut Member

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    Nice, thanks for the extensive explanation. I will just point out that 1) the increase in carbonic anhydrase was seen not only in aging but also in neurodegenerative conditions as the popular press article says. As it also says, this is what led to the statement by the authors that this chronic increase in carbonic anhydrase is pathological. In support, the artificial increase in carbonic anhydrase levels and activity (chronically) reduced maximum lifespan of the nematode model. So, while the article does not go into much detail, I think they consider the chronic increase in CA to be pathological. I also have no problem with the idea that acute rise in many things like estrogen, serotonin, CA, prolactin, etc is an attempt to correct an emerging pathology or at least controls further damage. Even in the acute stage, these biomarkers only tend to rise when underlying metabolism is low and cannot support proper recovery simply throgh ATP. But let's assume that acute elevation is beneficial. But the study is about chronically elevated CA and how it relates to both aging and health. Thus, I still think that chronic increase of CA is not just an attempt to fix a pathology but once at the chronic stage it contributes to the pathology directly. 2) Thiamine is a direct inhibitor of CA, as one of the studies I posted above shows and was in fact with similar K(i) to the known inhibitors like acetazolamide. Attached is the actual study and in the Conclusions section they explain why thiamine directly inhibits CA. So, I still claim that thiamine has a role as a direct and not just functional CA inhibitor.
     

    Attached Files:

  4. tyw

    tyw Member

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    Regarding point (2), yes, it seems that Thiamine does inhibit at least Human Red Blood Cell CA-2 via some mechanism.

    In that case, I view Thiamine with even more caution :bag:, and will consider this an addition to a list of Thiamine overdose precautions.

    ----

    Regarding (1), if we throw a tear gas canister into a crowd, the crowd will panic. Panicking people in the crowd directly confuse and cause harm to other people around them.

    How do we fix the situation? ....
    (a) get rid of the tear gas
    (b) calm the crowd down :bigtears: (through whatever means necessary, "non-moving" people are "calm" ....)

    The best answer is (a) then (b) through peaceful means, but regardless, both (a) and (b) must be done simultaneously in an optimal solution.

    If only one thing can be done, it is (a), and eventually the crowd will calm down naturally.

    Obviously a mob will perpetuate damage, but that isn't the cause for mob-mentality in the first place.

    I will flip the argument on to the views on Auto-immunity stated in the Generative Energy Podcast #12 -- #12: A Bioenergetic View of Autoimmunity

    The cause of so-called auto-immunity is damage to the cell. Once significant damage has occurred, the immune system is dys-regulated and confused, because now there is a whole bunch of jumbled up signals coming from the damaged cell and other cells around it. The unregulated signalling of damaged cells is the mob, and they directly worsen the situation -- at worse, by causing the immune system to attack its own tissues (this is possible, through the secretion of mild toxins that are meant for pathogens), at best, there is mis-allocated resources to the immune system which could have been used elsewhere.

    I contend that the same mechanics apply to forcible Carbonic Anhydrase inhibition.

    .....
     
  5. raypeatclips

    raypeatclips Member

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    @tyw (2) How come you view Thiamine with more caution, if it does directly inhibit CA? From my reading of this thread I assumed this would have a positive effect?
     
  6. tyw

    tyw Member

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    First, I will always assume that every compound has an optimal dose, with overdose always being a potential issue. Since haidut pointed out that Thiamine behaves just like any other powerful Carbonic Anhydrase Inhibitor, it will come with all the side effects, which have been documented in patients who have used it.

    Next, like I have described above, I do not think Carbonic Anhydrase inhibition is necessarily good.

    For me, this is just more information to look out for when judging a particular person's health status (whether or not Carbonic Anhydrase plays a significant role in their pathology). No recommendations to anyone are made.

    .....
     
  7. OP
    haidut

    haidut Member

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    As to your first point. If the crowd panics and starts a stampede, fixing a) won't do much good on its own. The stampede has already started and the crowd has a mind of its own. And once the stampede has started it tends to be a lot worse than the original reaction / damage to a relatively localized problem such as a single tear gas canister. Ideally, the panic reaction control and elimination of the original cause should happen simultaneously, not first a) and then b). A panicked crowed does not listen to reason once panic has set in and for that reason most public health policies focus on controlling the crowd first. "Fear is contagious" as they said in the great movie "K19 - the widowmaker".
    Anyways, let's say that we do not know the original cause for the panic - i.e. in this case the tear gas. Don't you think that we should be at least trying to control the panic? Imagine the crowd, a self-organizing entity with a dynamic quorum just like the cells in the body are actually capable of putting the tear gas canister out IF they could reverse the panic and focus on the problem at hand? I have seen it actually happen in real life and albeit rare it is quite inspiring to watch. The very real and physical sense of fear in the air gets replaced by a sense of resiliency and reason and the crowd starts to solve the problem instead of running around mindlessly. I think this is Peat's main point, which I understand is contested by some. Namely, if you control or even reverse the panic reaction, the crowd (cells) will quickly realize that the "tear gas canister" (infection, trauma, even cancer) is not an insurmountable problem and can form a coherent field through quorum and get rid of the original cause, even though it may be unknown to us. You can't have a quorum in a panic situation, so controlling/reversing the panic is paramount. And we have evidence collected over the last 100 years that cells in a non-panicked (low stress), stable environment can solve even very serious health problems whose original cause may be still unknown to us.
    Now, if you want to find out the original cause - by all means, I think this is the effort of biochemistry for the next century. But for practical matters, if cells are capable of solving health problems themselves then we should do everything to provide that panic-free, non-stressed environment, even it means sometimes "forcing" it through the use of diet, supplements or drugs. I guess my point is just that - we don't know what the original cause is in many cases but we have evidence that cells do and can fix it when functioning in an optimal environment. So, until we find out what that cause is let's at least provide that optimal environment.
    As far as thiamine - why do you think that it inhibits only CA-2? If you look at the attached image from the study it shows that thiamine inhibits CA-1, CA-2, and CA-6 all in nanomolar concentrations, which is considered pretty good even for a pharma drug. Yes, it was most effective for CA-2 but all of these nanomolar concentrations for the other isoenzymes are achievable with oral doses of thiamine available to everybody through a vitamin pill. I actually exchanged some emails with the study authors and they suspect thiamine inhibits not just CA-1, CA-2, and CA-6 but all 14 CA isoenzymes, and all of them in nanomolar concentrations! I am waiting for them to send me the results for the other isoenzymes and will post here.
     

    Attached Files:

  8. Tarmander

    Tarmander Member

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    Great thread guys. I will add, from an experimental standpoint, tyw' point that thiamine is probably both a CA inhibitor as well as having many other beneficial effects is probably accurate. My experiment with high doses of thiamine over a many month period gave me some of the pharmaceutical side effects talked about with CA inhibitors. Namely loss of appetite, depression, and metallic taste. However there were obvious good effects on energy. I look forward to further discussion.
     
  9. tyw

    tyw Member

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    Preface: this was written on a Sunday morning. I am ranting :penguin:. Do not expect a high level of coherence.

    ----
    High Level

    @haidut Yes :android:

    I said that the ideal solution is to do both. But if only one action can be done, it is to remove the root cause of the stress.

    The difference between cells and people (and where the analogy breaks down), is that cells are:
    (1) Potential slaves to particular signalling routes :borg:
    (2) Are largely expendable :droid: (except for a few select tissues), and potentially replaceable

    In the linked post at the end of this sentence, I talk about how the concept of Cell Intelligence, which is driven by metabolism, can lead to good decision-making -- Metabolic Efficiency And Metabolic Rate - Doubt

    Note that in that thread in the last link to the 'Metabolic Efficiency' thread, haidut asked (link to haidut's post):

    My point is that while using steroids for treatment is probably still relevant, the master conductor of all such messengers is probably T3. So, instead of chasing down each messenger, why not try to tweak the conductor?

    ....

    Instead of trying to look at each condition separately, which could work but is probably intractable in practice, why not focus on the one (or few) master controllers of the quorum? T3, ATP, CO2, insulin, etc are a few of the main ones that come to mind but the latter two depend on T3.​

    My answer to that has been that, in practice, sick cells more often than not do to not respond to these High Level Conductors. As observational proof of that, I cite the many many people with varying conditions who simply fail to respond to hormones. eg: I've know quite a few ladies with PCOS, who are on something like, 100mg of Progesterone, 500mg of Pregnenolone, plus lots of T3, and yet not seeing any effect. Sometimes the T3 even leads to weird side effects like extreme nausea ... we can also see many people on this forum with such issues, though I will not name them.

    Note: there is obviously a "hierarchy of conductors" though .... for example, testosterone seems to be an "un-ignorable conductor". But Progesterone or T3? Those fail to achieve their normal impact pretty damn frequently in sick people.​

    We can discuss some of these topics mechanistically. For example, haidut has discussed how PUFAs can potentially inhibit Thyroid Receptor activity. I have then added to that the fact that in many people, they are going to have high serum PUFAs for a period of time, despite not.

    I will judge practical results first and foremost, and the theory doesn't end up being clean when we are dealing with complex regulatory mechanisms.

    Haidut also says in that post:

    Cellular communication also breaks down in diabetes, not just in cancer, and the quorum method has been shown to work for reversing it just as in cancer​

    And my answer to that is: actually, there are many cases of quorums being able to be established. The success of something crazy like Fecal transplants shows that small changes in particular parts of the system can cause massive systemic changes through the entire body.

    And if that fails, is it because there wasn't a strong enough majority in the quorum. This could be due to putting the "healthy tissues" in the wrong place, whereby they cannot effectively establish a quorum (just like back in the day, "Vice President of the US" didn't mean much ... unless you were Teddy Roosevelt ..... well, the point is that the Vice President is supposed to only be as powerful as the President allows them to be, unless fate intervenes).

    Another explanation for quorum failure is that there wasn't enough healthy tissue to go around.

    Another explanation is that the surrounding tissues were too sick to begin with.

    Regarding that last statement, I have to respond with another question: If metabolism generates cell intelligence, and cell intelligence allows for better metabolism, how does metabolism fail in the first place? Shouldn't this be a self-reinforcing loop?

    This is why IMO, we need to take the Chinese Medicine perspective, and look at "The 4 factors of Channel injury":
    (1) Physical Strain / Overuse
    (2) Invasion of External Pathogens
    (3) Injury (eg: actual physical trauma)
    (4) Internal Organ Imbalance (in Chinese medicinal terms, imbalance between "Yin" and "Yang", which have specific meanings based on each organ)

    Either one of these must cause damage to a set of tissues, in order to fundamentally disrupt metabolism and cell intelligence from the base level. That is in part why I stress the importance of stuff like "getting rid of infections", and "ensuring healthy fascia". And of course, what happens when people are actually missing body parts? be it a gallbladder, a limb, their tonsils, a kidney, or hell, even their thyroid ..... More complications galore.

    Sidenote: fun convo with Dr Josh Lamaro on fascia


    The only thing I will recommend that people do, is to absorb what information they can, periodically question their existing experiments, and take responsibility to tweak things as needed according to real-world results.

    -----

    CA-2 and other CAs

    We must remember that CA-2 is found ubiquitously through cell cytosol, and is no tissue specific. Thus, any CA-2 inhibitor is also going to act on tissues non-specifically.

    From an analytical standpoint, this means that we have no clue which tissues are actually most affected in a particular person, and do not have any basis to do so.

    The fact that Thiamine affects a lot of the alpha CAs, makes the effects of Thiamine even less predictable.

    Mechanistically, my best guess is that carbonic anhydrase activity seems to "balance out" CO2 concentrations. H2CO3 is thought to be more readily transportable in water, and Carbonic Anhydrase will create more H2CO3 when CO2 is high and H2CO3, while creating more CO2 when H2CO3 is high and CO2 is low.

    What makes us think that this is a good or bad thing? The answer is that we do not know yet, because we do not understand the mechanistic effects of this balance between the "different forms of CO2". Again, it is not as simple as more CO2 is better ... where? for how long? under what requirements? etc .....

    A correlation "more Carbonic Anhydrase activity with Ageing" is a hypothesis generator, not a source for practical recommendation. The same can be said for the cholesterol correlation of "more cholesterol associated with X disease state", whereby today, we have mechanistic explanations for how cholesterol is there as a support mechanism in those disease states, and usually not an added stressor.

    Final Sidenote: as another example of why we must be careful with associations, is because seemingly "bad" compounds have uses in the body.

    Here is one case, whereby Nitric Oxide is Required to prevent the formation of atherosclerotic plaques, but only when used in context of the appropriate mix of compounds (of which cholesterol-sulfate plays primary role) -- http://www.tbiomed.com/content/12/1/9/abstract

    If there is a case of chronic heart damage due to some stressor, then there will also be chronic low-level Nitric Oxide used to replace those damaged tissues. Blocking Nitric Oxide indiscriminately (if possible) without fixing the base level stressor causes the problem to get worse. Fix the root stressor, and then the body doesn't need to produce that extra Nitric Oxide.​

    ----

    And to repeat :bag:, the only thing I will recommend that people do, is to absorb what information they can, periodically question their existing experiments, and take responsibility to tweak things as needed according to real-world results.

    ....
     
  10. opiath

    opiath Member

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    Carbonic anhydrase is crucial to the production of stomach acid, tears, saliva and other secretions.
    I don't see how inhibiting it would bring positive results. Especially for people with metabolic problems.
    You get more CO2, but this comes at the price of blocking one it its essential functions.
    If high dose thiamine inhibits CA, it might be counterproductive to use it for fixing low stomach acid.
     
  11. ilikecats

    ilikecats Member

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    @haidut Just got this fascinating little nugget of info from Ray : “Progesterone is the body’s natural carbonic anhydrase inhibitor (estrogen has the opposite effect)”

    Very cool

    He also sent me a study that showed a 4-fold increase in hepatic carbonic anhydrase in rats treated with estrogen.
     
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