Wednesday 24 June 2015

Altered Homeostasis in Autism: Cl-, K+, Ca2+, and quite possibly Zn2+

Today’s post will highlight how, perhaps, in 50 years’ time, autism might be understood by the non-scientist.  Sometimes it helps to oversimplify a complex problem in order not to get lost in all the complexities and see what underlying mechanisms may exist.


Homeostasis is a fancy word for balance or equilibriumIt is the property of a system in which variables are regulated so that internal conditions remain stable and relatively constant.

All living organisms depend on maintaining a complex set of interacting metabolic chemical reactions. From the simplest unicellular organisms to the most complex plants and animals, internal processes operate to keep the conditions within tight limits to allow these reactions to proceed. Homeostatic processes act at the level of the cell, the tissue, and the organ, as well as for the organism as a whole.

Many diseases involve a disturbance of homeostasis.

Autism is clearly a condition of altered homeostasis, but not severe enough as to become degenerative.

First Chloride Cl-, Calcium Ca2+ , then Potassium K+ and now perhaps Zinc Zn2+

We have already seen that three very simple ions, chloride Cl- , calcium Ca2+, potassium K+ are in the “wrong place” or in the “wrong concentration” in autism.  This in effect tells us that there is altered homeostasis.

Would it then come as a surprise that a fourth ion, zinc Zn2+ also appears to be in the “wrong place”, in at least some autism?

Perhaps there is a common mechanism behind this dysfunctional homeostasis? It might be related to cell adhesion molecules like neuroligins (see below), which will be looked at in another post.

Source: By Sarahlobescheese (Created on Paintbrush and Microsoft Word) [GFDL ( or CC BY-SA 3.0 (], via Wikimedia Commons

Supplementation and Homeostasis

When the lay person hears that something simple is involved in the pathology of autism, the immediate reaction seems to be that you either need more, or less, of it.  So more calcium, more zinc, more magnesium etc.

The problem is more complex; there is enough calcium (and your bones are full of it) but it is not all quite in the right place, so it needs moving around a bit.

When I came across the recent research from Taiwan about the effect of zinc on the NMDA receptors in the brain, I did a quick check and found lots of people supplementing zinc. Some people because the level in their child’s hair was high and some because it was low; the therapy remained the same, more zinc.

Just as Ben-Ari really has figured out many aspects of the excitatory/inhibitory imbalance in GABA in autism and chosen a therapy that indirectly corrects it, the Taiwanese have also gone into their receptor, the NMDA, in detail.  They put forward a well thought out case for modulating it.

Just as Ben Ari choose to move chloride to outside the cells with his drug (Bumetanide), Yi-Ping Hsueh, the Taiwanese researcher, uses an existing  drug called Clioquinol to move zinc from a presynaptic terminal to postsynaptic sites in the brain.  Again, like Ben Ari, she also showed it to be effective in two different mouse models of autism.

“Here we report that trans-synaptic Zn mobilization rapidly rescues social interaction in two independent mouse models of ASD. In mice lacking Shank2, an excitatory postsynaptic scaffolding protein, postsynaptic Zn elevation induced by clioquinol (a Zn chelator and ionophore) improves social interaction. Postsynaptic Zn is mainly derived from presynaptic pools and activates NMDA receptors (NMDARs) through postsynaptic activation of the tyrosine kinase Src. Clioquinol also improves social interaction in mice haploinsufficient for the transcription factor Tbr1, which accompanies NMDAR activation in the amygdala. These results suggest that trans-synaptic Zn mobilization induced by clioquinol rescues social deficits in mouse models of ASD through postsynaptic Src and NMDAR activation

Scientists compared the interactions of test mice by placing the subjects in a box, mice that had been unchanged, mice with their Tbr1 and Shank2 proteins “knocked off” and another “stranger” mouse.
They found that unchanged mice engaged in high-level interaction with the “stranger” mouse, while mice with Tbr1 and Shank2 deficiencies interacted very little.
Hsueh’s team had previously determined that Tbr1 is a contributing factor of autism, while a team led by South Korean scientist and project coleader Eunjoon Kim discovered that Shank2 is also implicated in the condition.
Both deficiencies hamper the transmission of zinc ions to the NMDAR (N-methyl-D-aspartate) receptor, impairing function.
About 30 percent of children with autism suffer from zinc deficiency.
Hsueh said that previous projects had determined that autism is linked to zinc deficiency, but the research undertaken by Academia Sinica and the South Korean researchers is the first to provide a scientific explanation for the phenomenon by establishing that the social inhibitions caused by autism can be changed by revitalizing the NMDAR receptor.
Hsueh said the results from the experiment conducted on mice can be extrapolated to humans, with a higher than 90 percent relevance between the two species.
She said that as clioquinol is a prescription drug permitted in Taiwan, her team hopes psychiatrists will prescribe the drug to suitable patients.

Zinc Deficiency or Zinc Transmission Deficiency?

A quick review of the research does show very odd levels of zinc in people with autism.  It also transpires that different ways of measuring zinc levels (hair, blood etc) can produce the opposite result.  So it is hard to ascertain that somebody really does have a zinc deficiency.

The key point is the transmission of that Zinc to the NMDA receptors in the brain.  Note the Zn2+ modulatory site in the diagram below.


Clioquinol, has a very tainted past in Japan. The drug was widely used for various conditions in the 1960s, at doses higher than in other countries.  Its use was tied to the emergence of a new condition called Subacute myelo-optico-neuropathy (SMON) , which only seems to have occurred in Japan.

Clioquinol is banned in some countries, but widely available in other countries, like Taiwan,

Clioquinol is showing promise in research into Alzheimer’s.

Some argue that Clioquinol is totally safe and argue for a combined therapy of Clioquinol and zinc.


These studies suggest that oral CQ (or other 8-hydroxyquinolines) coupled with zinc supplementation could provide a facile approach toward treating zinc deficiency in humans by stimulating stem cell proliferation and differentiation of intestinal epithelial cells.


Subacute myelo-optico-neuropathy (SMON) is a disease characterized by subacute onset of sensory and motor disorders in the lower half of the body and visual impairment preceded by abdominal symptoms. A large number of SMON were observed throughout Japan, and the total number of cases reached nearly 10,000 by 1970. Despite clinical features mimicking infection or multiple sclerosis, SMON was confirmed as being caused by ingestion of clioquinol, an intestinal antibacterial drug, based on extensive epidemiological studies. After the governmental ban on the use of clioquinol in September 1970, there was a dramatic disappearance of new case of SMON. In the 1970s, patients with SMON initiated legal actions against the Government and pharmaceutical companies, and the court ruled that the settlements would be made as health management allowances and lasting medical check-ups. The physical condition of patients with SMON remains severe owing to SMON as well as gerontological complications. The pathological findings in patients with SMON included symmetrical demyelination in the lateral and posterior funiculi of the spinal cord and severe demyelination of the optic nerve in patients with blindness. Although clioquinol may show activity against Alzheimer's disease or malignancy, its toxic effects cause severe irreversible neurological sequelae. Thus, caution must be exercised in the clinical use of clioquinol

Zinc is an essential micronutrient that accumulates in brain and is required for normal development and function. Both deficiency and excess of zinc alter behavior and can cause brain abnormalities and neuropathies, of which epilepsy, ischemia, and Alzheimer’s degeneration have been the most studied. Aside from catalytic and structural functions in many proteins, ionic zinc (Zn2+) may play important roles in neurotransmission. Free Zn2+ accumulates in the synaptic vesicles of a specific subset of glutamatergic neurons and is coreleased with glutamate in an activity-dependent manner. Upon release, free Zn2+ may modulate neurotransmitter receptors and transporters, activate zinc-sensing metabotropic receptors, and/or gain cellular access through Ca2+-permeable channels. At certain glutamatergic synapses, a primary role for vesicular zinc is to reduce N-methyl-D-aspartate (NMDA) receptor currents . A wide range of extracellular Zn2+ concentrations directly and specifically inhibit NMDA receptor responses, and in the hippocampus, a region highly enriched in vesicular zinc, zinc-positive glutamatergic synapses are also enriched in NMDA receptors. The inhibitory effects of Zn2+ on NMDA receptors have received considerable attention due in part to the pivotal role played by these receptors in synaptic transmission and plasticity. Still, the mechanism by which the inhibition occurs is incompletely understood.

Other ways of modifying NDMA receptors

As the excellent recent paper below from Korea points out,correcting NMDAR dysfunction has therapeutic potential for ASDs”.  The problem is that in some autism there is too much NMDAR function, and in others there is too little.

So we should not expect much success from any “one size fits all” therapy.

NMDA receptor dysfunction in autism spectrum disorders.

Abnormalities and imbalances in neuronal excitatory and inhibitory synapses have been implicated in diverse neuropsychiatric disorders including autism spectrum disorders (ASDs). Increasing evidence indicates that dysfunction of NMDA receptors (NMDARs) at excitatory synapses is associated with ASDs. In support of this, human ASD-associated genetic variations are found in genes encoding NMDAR subunits. Pharmacological enhancement or suppression of NMDAR function ameliorates ASD symptoms in humans. Animal models of ASD display bidirectional NMDAR dysfunction, and correcting this deficit rescues ASD-like behaviors. These findings suggest that deviation of NMDAR function in either direction contributes to the development of ASDs, and that correcting NMDAR dysfunction has therapeutic potential for ASDs.

Pharmacological modulation of NMDAR function can improve ASD symptoms. D-cycloserine (DCS), an NMDAR agonist, significantly ameliorates social withdrawal  and repetitive behavior  in individuals with ASD.

These results suggest that reduced NMDAR function may contribute to the development of ASDs in humans. Elevated NMDAR function is also implicated in ASDs. Memantine, an NMDAR antagonist, and its analogue amantadine improve ASD-related symptoms including social deficits, inappropriate language, stereotypy, cognitive impairments, lethargy, irritability, inattention, and these results, together with the DCS results, highlight the importance of a normal range of NMDAR function, and suggest that deviation of NMDAR function in either direction leads to ASD.  This concept is in line with the emerging view that synaptic function within a normal range is important and its deviation causes ASDs and intellectual disability

Mice lacking neuroligin-1, an excitatory postsynaptic adhesion molecule, show reduced NMDAR function in the hippocampus and striatum, as evidenced by a decrease in NMDA/AMPA ratio and long-term potentiation (LTP) Neuroligin-1 is thought to enhance synaptic NMDAR function, by
directly interacting with and promoting synaptic localization of NMDARs.

CDPPB, a positive allosteric modulator of mGluR5 that potentiates similarly normalizes NMDAR Dysfunction and behavioral deficits, consistent with the idea that indirectly modulating NMDARs through mGluR5 is a viable approach for treating ASDs.

ASDs involve diverse core and comorbid symptoms. Consistent with this, a single autism-related mutation, neuroligin-3 R451C, causes diverse synaptic phenotypes in different brain regions and circuits. Therefore, synaptic changes should be analyzed in greater detail, ideally using brain region-specific and cell type-specific conditional gene ablation, as recently reported.

Modulators of mGluR5, in addition to NMDARs and AMPARs, have been considered to be a new means of regulating glutamatergic transmission. Therefore, pharmacological rescue of animal models of ASD should ideally involve modulation of both NMDARs and mGluR5, or even other NMDA-modulatory approaches, to better facilitate translation to clinical therapy.

Lastly, because our hypothesis associates bidirectional NMDAR dysfunction with ASDs, there may be clinical cases, such as where individuals with reduced NMDAR function are treated with NMDAR antagonists, which might aggravate the situation and affect the interpretation.

None of the existing autism therapies that modify NDMA receptors have been uniform knockout successes, but are effective in some cases.

These include:-

·        Memantine an NMDAR antagonist
·        D-Cycloserine an NMDAR agonist (the opposite of Memantine)

·        Ketamine, an NMDAR antagonist

So if you respond to Memantine, the chances are you would benefit from intranasal ketamine;  but D-Cycloserine would make you worse.

They recently terminated early the large Memantine autism trial.  In a rational world they would try D-Cycloserine on all those kids who failed to respond to Memantine.  We do not live in a rational world.


I have a feeling that several dysfunctions in autism, including the E/I imbalance of GABA, will ultimately be traced back to neuroligins.

This is an area of science in its infancy and so for today we have to treat the consequences individually. 

Fortunately, the Simons Foundation is funding the right people and so, in the end, we will get to the bottom of it all.

I hope the Taiwanese test Clioquinol on some humans with ASD and let us know the results.  

As the clever Korean researcher above has highlighted, Clioquinol will only benefit those with reduced NMDAR function.  So if I have got things the right way round, Clioquinol will help the same group that respond to D-Cycloserine.  The others would need Memantine/Ketamine, or even better, they have perfect NMDAR function and need nothing at all.


  1. Hi Peter,
    I just started supplementing potassium + magnesium with good results, and this lead me to see channelophaties with more care.
    I have noticed that the NKCC function is dependent on ATP, and as such impacted by mitochondrial function.

    This would mean that bumetanide effectiveness would be negatively impacted until mitochondrial funcion is improved for some kids with R-ASD / AMD like my son.
    I assume this from this older post:
    (Maybe this is worth sharing with non respondents to bumetanide???)

    Verapamil should not be impacted because it acts as a blocker not a transporter, right?

    Here the source of my info:
    "The majority of this ATP production by a non-photosynthetic aerobic eukaryote takes place in the mitochondria..."

    "The energy required to move solutes across the cell membrane is provided by the electrochemical gradient of sodium. Sodium's electrochemical gradient is established by the Na-K ATPase, which is an ATP-dependent enzyme. Since NKCC proteins use sodium's gradient, their activity is indirectly dependent on ATP; for this reason, NKCC proteins are said to move solutes by way of secondary active transport."

    "Since this carrier enzyme (Na+-Ca2+ translocator) uses the Na gradient generated by the Na+-K+ pump to remove Ca2+ from the intracellular space, slowing down the Na+-K+pump results in a permanently elevated Ca2+ level in the muscle, which may be the mechanism of the long-term inotropic effect of cardiac glycosides such as digoxin." (NOTE: I imagine this is true for wherever there is NA+-K+ pump, so it would apply to brain as well...)



    1. Most things seem to be inter-related. In people with autism secondary mitochondrial disease, it really means that. Mitochondrial disease is the #1 problem and needs to be solved first. I am not sure that all people with regressive autism have mitochondrial disease, they may "just" have mitochondrial dysfunction caused by their type of autism.

      Verapamil is very interesting because it will affect all L-type calcium channels and they are all over the place. Most neurotransmitter receptors have calcium channels. So I think even in times of flare-ups verapamil will still "work". Verapamil may also help mitophagy.

      I will shortly make a post on some possible mitochondrial therapies using Mito E, Mito Q, high dose Melatonin and a Russian H1 antihistamine called Dimebon.

    2. My 4 year old asperger son was treated 8 days with clioquinol for a parasite
      infection. Althoug we did have some behaviour difficulties after the 4th day from the start probably
      because of parasite die off, after that we saw a very improved ASD behaviour that lasted
      till about 5 days after stopping clioquinol. I could communicate like a normal 4 year old child but after 5 days the difficult communication and brainfog symptons started again.

      The improvement in behaviour was something spectacular for us. I was really afraid for clioquinol
      because of SMON but it seems we have at least had a very short and very positive reaction. It could be that it was the parasite that was almost dead but is now back again. Or it could be the NMDAR that was stimulated. Soon we will recheck the parasite so we have a bit more clue about what was going on.

      Peter, what other tests could I do to retest NMDAR theory? Could it be that some herbs or easy over the counter supplements could similate the clioquinol effects that we saw?

      Starting clioquinol again is not possible, there should be at least 2 months between treatments and some even say that you only should use it a couple of times in your life to prevent from neurotoxic damage and the damage could build up.

      I also did a very complete urine/hair/feces test 5 months ago that revealed some typical issues that are often seen in ASD like candida, bad gut flora, high oxalates and problems with PST (sulphur transfase) and low in gluthatione. I am already 4 months working on that with some improvement and soon I have to retest again. We started glutenfree and caseinfree and give magnesium citrate and molybdeum for PST and try to avoid oxalates a bit but we did not see the "WOW" effect that we saw with clioquinol last weeks. We were not the only one who saw it, we heard it from school and family too.


    3. Robert, it seems that most people with Aspegers benefit from baclofen, which is a drug that affects GABABb receptors that counters the defect in NMDA receptors. This was shown in a mouse model, but the effect in Aspergers is based on use in humans. So I would try say 5mg of baclofen two or three times a day.

      Based on what the Taiwanese said in their study you could also try a zinc supplement.

      I think you have much greater than 50% chance of success with baclofen.

  2. Hi Peter,

    What would the behavioral differences be with those that would benefit from D-cycloserine vs the Memantine group?

    1. A very good question. It seems that too much and too little NMDA function leads to "social withdrawl". This is suposed to be a core feature of autism, but it certainly is not (now) in my son's case. It looks like something for people with Aspergers who often report anxiety.

  3. KCC2 is downregulated by many factors (BDNF, oxidative stress, hyperexcitability) and paradoxically upregulated by BDNF plus a tyrosine kinase inhibitor and/or a PLC gamma inhibitor as both pathways need to be activated to downregulate KCC2, but if one pathway is inhibited, then KCC2 goes up. Curcumin and Genistein are decent tyrosine kinase inhibitors, so perhaps since Bumetanide affects NCCC1 (pumping chloride in) and NCC2 transports chloride out, it might make sense to try and set a new homeostasis for interneurons by dealing with intracellular chloride levels at both ends, while at the same time trying to minimize stresses that downregulate NCC2 as the downregulation of NCC2 can lead to epileptic like activity which causes more surrounding stress which would seem to then cause even more downregulation of NCC2 if I understand things correctly (i.e a nasty feedback loop that can get out of hand if chloride homeostasis is messed up to begin with)

  4. Thank you for this blog post Peter. I was beginning to wonder if theres any hope for us. My daughter may have issues with a different cell adhesion molecule- the cadherins. Promethease reports that she has rs4307059(T;T) and that per my reading from has a high correlation with autism. Have you come across anything that might help with this?

    1. "Individuals who carry the ASD-associated rs4307059 T allele showed increased expression of MSNP1AS. The MSNP1AS noncoding RNA bound to MSN, was highly overexpressed (12.7-fold) in postmortem cerebral cortex of individuals with ASD, and could regulate levels of moesin protein in human cell lines."

      So it looks like you would want to reduce the level of Moesin Protein.

      This would need an ezrin deactivator.

      One such substance appears to be Ceramide (read the above paper)

  5. Thank you for the reply Peter!

  6. Peter:
    My son with autism has symptoms that are social Isolation, hyperactivity, delayed responses, not very verbal. Some wiggling & extra arm movements. His Immunologist prescribed Amantadine due to the Cunningham Panel outcome and that worked very well for 4 weeks, he was calm more social, less wiggling and more with it. After 4 weeks he started crying all the time for hours and telling me his head hurt. We stopped the Amantadine. Can you tell me if he just needed a break from Amantadine then re-start or what you might think of this.
    Thank you

    1. Amantadine has multiple modes of action and it looks like one of which causes your son's head to hurt. There are other drugs used for PANS/PANDAS and it might be a good idea to try a different drug to find one that he tolerates and gives a good effect.

      I would go back and talk to the immunologist. He should know about the side effects and if they fade over time.

  7. My son is on amantadine... as are some of his friends... we note problems if you increase dose TOO quickly... dose needs to be increased very very very .25 ml every 5 days...going up to fast causes emotional outbursts and adjustment problems.


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