Modulating Wnt Signaling in Autism and Cancer

Source: LDL receptor-related proteins 5 and 6 in Wnt/β-catenin signaling: Arrows point the way

In earlier posts I have covered various signaling pathways such as Wnt, mTOR and the unusually sounding Hedgehog.

You can go into huge detail if you want to understand these pathways, or just take a more superficial view. In most cases, things only start to go wrong if you are hypo/hyper (too little/too much) in these pathways.

We saw with mTOR that most people with autism are likely to have too much activity and so might benefit from mTOR inhibition, but a minority will have the opposite status and stand to benefit from more mTOR activity.

When it comes to Wnt signaling the research suggests the same situation. Wnt signaling is likely to be aberrant, but both extremes exist.

Wnt signaling networks in autism spectrum disorder and intellectual disability

Given the large volume of genetic data, analyzing each gene on its own is not a feasible approach and will take years to complete, let alone attempt to use the information to develop novel therapeutics. To make sense of independent genomic data, one approach is to determine whether multiple risk genes function in common signaling pathways that identify signaling “hubs” where risk genes converge. This approach has led to multiple pathways being implicated, such as synaptic signaling, chromatin remodeling, alternative splicing, and protein translation, among many others. In this review, we analyze recent and historical evidence indicating that multiple risk genes, including genes denoted as high-confidence and likely causal, are part of the Wingless (Wnt signaling) pathway. In the brain, Wnt signaling is an evolutionarily conserved pathway that plays an instrumental role in developing neural circuits and adult brain function.

While the human genetic data is an important supporting factor, it is not the only one. There are a number of mouse genetic knockout (KO) models targeting Wnt signaling molecules, describing molecular, cellular, electrophysiological, and behavioral deficits that are consistent with ASD and ID. Furthermore, the genes involved in Wnt signaling are of significant clinical interest because there are a variety of approved drugs that either inhibit or stimulate this pathway.

There are many drugs developed and tested as modulators of Wnt signaling in the cancer field that could potentially be repurposed for developmental cognitive disorders. In cases where a reduction in Wnt signaling is thought to underlie the pathology of the disorder, usage of compounds that elevated canonical Wnt signaling could be applied. An example of this is GSK-3β inhibitors that have failed in cancer trials but may be effective for ASDs and ID (e.g., Tideglusig, ClinicalTrials.gov identifier: {"type":"clinical-trial","attrs":{"text":"NCT02586935","term_id":"NCT02586935"}}NCT02586935). In cases where elevated Wnt signaling is thought to contribute to disease pathology, there are many potential options to inhibit canonical Wnt signaling using chemicals (Fig. 1) that inhibit the interaction between β-catenin and its targets (e.g., inhibiting β-catenin interaction with the TCF factors), disheveled inhibitors (through targeting of the PDZ domain which generally inhibit the Frizzled–PDZ interaction), and tankyrase inhibitors (e.g., XAV939, which induces the stabilization of axin by inhibiting the poly (ADP)-ribosylating enzymes tankyrase 1 and tankyrase 2)

As autism candidates emerge, cancer pathway rises to top

In recent years, strong autism ties have cropped up for one group of genes in particular: those that make up a well-known signaling pathway called WNT, which also has strong links to cancer. This pathway is especially compelling because some people with autism carry mutations in various members of it, including one of its central players: beta-catenin¹. What’s more, studies from the past year indicate that several of the strongest autism candidate genes, including CHD8 and PTEN, interact with this pathway.

“There might be a particular subgroup of genes associated with autism that could all be feeding into or be regulating this pathway,” says Albert Basson, reader in developmental and stem cell biology at King’s College London, who studies CHD8 and WNT. “That clearly has emerged as a relatively major theme over the last few years.”

The connection between cancer and some autism is over-activated pro-growth signaling pathways. Many signaling pathways have growth at one extreme and cell death at the other. In cancer you actually want cell death to suppress tumor growth; in much autism there is also too much growth.  

Many cancers are associated with elevated signaling of mTOR, Wnt and indeed Hedgehog.  These are targets for cancer drug therapy and so there is already a great deal known.

A complication is that in a developmental neurological condition, like autism, it also matters when these signaling pathways were/are disturbed. For example Wnt signaling is known to play a role in dendritic spines and synaptic pruning, some of this is an ongoing process but other parts are competed at an early age, so it would matter when you intervene to modulate these pathways.

Historically cancer therapies involve potent drugs, often with potent side effects, however in recent years there has been growing awareness that some safe existing drugs can have equally potent anti-cancer effects. Many of these drugs are anti-parasite drugs, but even the very widely used diabetes drug Metformin has been shown to have significant anti-cancer effects, not to forget Simvastatin.

Many autism pathways/genes play a role in cancer (RAS, PTEN) and the upstream targets considered in cancer research are also autism targets.  For example many human cancers are RAS dependent and in theory could be treated by a RAS inhibitor, but after decades of looking nobody has found one. So instead scientists go upstream to find another target that will indirectly reduce RAS. This led to the development of PAK1 inhibitors that will reduce RAS.

RAS plays a role in some types of intellectual disability and indeed autism. The collective term is RASopathy.  Logically, drugs that modulate RAS to treat cancer might be helpful in modulating RAS for some autism.

Most types of cancers are complex and so there are multiple potential targets to attack them, but also the same target can have multiple possible approaches. RAS dependent cancers can be targeted via Wnt and even Hedgehog signaling.

This may sound all very complicated but does it have any relevance to autism?

It apparently does because almost all these pathways are known to be disturbed hypo/hyper in autism.  This means that clever insights developed for cancer can be repurposed for autism.

Anti-parasite drugs and Cancer

It is indeed remarkable how many anti-parasite drugs have an anticancer effect and indeed there is a much maligned theory to justify this.

Clinical Evaluation of a New Form of Cancer Therapy Based on the Principles of Atavistic Metamorphosis

Quite possibly it is just a coincidence.

There are many ways to kill parasites, one of which involves starving them of ATP. ATP is the fuel that is produced in your mitochondria.

Cancer cells and many parasites use a very inefficient way to produce ATP that does not require oxygen. In normal human cells the process followed is known as OXPHOS, by which glucose and oxygen from the blood is converted into ATP (energy) is very efficient. Only when you run low on oxygen, like a marathon runner at the end of the race, can you run into trouble because there is not enough oxygen for OXPHOS.  What happens next is anaerobic respiration, when a different process takes over to make ATP. It is much less efficient and causes lactic acidosis which makes marathon runners' muscles hurt.

A cheap anti-parasite drug Pyrvinium targets anaerobic respiration and starves the parasite of ATP and thus kills it. Another common children’s anti-parasite drug albendazole also works by starving the parasite of ATP.

Other anti-parasite drugs work in different ways.

We already know from the autism trials of Suramin, another anti-parasite drug,  that it works via P2X and P2Y purinergic channels.

Ivermectin  binds to glutamate-gated chloride channels (GluCls) in the membranes of invertebrate nerve and muscle cells, causing increased permeability to chloride ions, resulting in cellular hyper-polarization, followed by paralysis and death.  Fortunately in mammals ivermectin does not cross the BBB.

Ivermectin is also a PAK1 inhibitor and a positive allosteric modulator of P2X7.

Both PAK1 and P2X7 are relevant to many cancers and so not surprisingly research shows that Ivermectin has an anti-cancer effect.

Ivermectin appears to have a positive effect in some autism, but strangely it does not cross the BBB.

Mebendazole is another extremely cheap children’s anti-parasite drug which has remarkable potential anti-cancer properties. It inhibits hedgehog signaling and, via the inhibition of TNIK, it is a Wnt inhibitor.

Unfortunately in the US the private sector has also noticed the anticancer effects of Mebendazole and albendazole and they have recently become astronomically expensive. Mebendazole (MBZ), which costs almost nothing in many countries, now costs hundreds of dollar per dose in the US under the name Emverm. Outside of the US, Mebendazole is OTC in many developed countries. In poor countries it is donated free by big pharma.

In the cancer research they consider taking advantage of the fact that cimetidine (a cheap H2 antihistamine) interacts with Mebendazole to increase its bioavailability. Cimetidine is by chance another generic drug also being considered to be repurposed for cancer.

While some anti-parasite drugs like Suramin have side effects or cannot be taken regularly like Ivermectin, others are seen as safe for continued use even at high doses (e.g. Mebendazole and albendazole).  

Anti-parasite drugs and Autism

Just as many anti-parasite drugs seem to have a positive effect on some cancers it looks likely that the same may be true for autism.  This does not mean that parasites cause either cancer or autism.

We know from Professor Naviaux that some people respond to Suramin.

Two people who comment on this blog have found their child responds to PAK1 inhibitors, one of which is the drug Ivermectin.

There are groups of people on the internet who think parasites cause autism and you will find some of them if you google “autism mebendazole”, but there are some very valid reasons why some people’s autism may respond to mebendazole, but nothing to do with little worms.

Potency of Anticancer drugs

Failed anticancer drugs are already considered as possible drugs to treat neurological conditions.

The same pathways do seem to be involved in some cancer and some neurological conditions, but the severity by which that pathway is affected may be very different, so a new drug may lack potency to treat a type of cancer but be potent enough to benefit others.

In the case of the anti-parasite drugs Ivermectin and indeed mebendazole the dosage being used in current cancer studies are very much higher than normally used.

Very little mebendazole makes its way out of your intestines and so researchers counter this by using a dose 15 times higher and even taking advantage of the interaction with the H2 antagonist cimetidine to boost bioavailability.

The standard human dose of Ivermectin is 3mg, but in the cancer trials (IVINCA trial - IVermectin IN CAncer) in Switzerland and Spain the trial dose is 12, 30 and 60 mg.

So when it comes to autism and the possible repurposing of these drugs, the cancer studies will give valuable safety information, but the likely dose required to fine-tune these signaling pathways will likely be a tiny fraction of the cancer dose.

The newly developed cancer drugs that fail in clinical trials, may have potential in autism but it is unlikely that anyone will develop them, test them and bring them to the market.

The clever thing for autism seems to be to keep an eye on the existing generic drugs considered to benefit the overlapping cancer pathways.

Conclusion

Aberrant Wnt signaling has been identified by researchers as playing a key role in autism; the Simons Foundation is among those now funding further research.

In practical terms you can be either hypo or hyper, but hyper seems more likely. It may be a case of shutting the stable door after the horse has bolted, because the ideal time to modulate Wnt signaling is probably as a baby, or before. Nonetheless some older people may indeed benefit from modulating Wnt; the Simons Foundation must also believe so.

In the case of people with hyperactive Wnt signaling, there is a case to make for the potential use of the cheap anti-parasite drug Mebendazole.

The drug Mebendazole (MBZ) can found in three states/polymorphs called Polymorph A, B or C. This is relevant because they do not cross the blood brain barrier to the same extent.

Brain Penetration and Efficacy of Different Mebendazole Polymorphs in a Mouse Brain Tumor Model  

To treat brain tumors, or indeed potentially some autism, you need MBZ-B or MBZ-C, it looks like MBZ-A does not cross the blood brain barrier.

Fortunately, MBZ-C is  the polymorph found most commonly in generic mebendazole tablets.  

Ivermectin is known not to cross the blood brain barrier but yet has been shown to show anti-tumor activity in brain cancer. The anti-cancer effect is thought to be as a PAK1 inhibitor, but this effect must be occurring outside the brain. Some people do use Ivermectin for autism.

The people using Ivermectin for autism are told they cannot use it continuously. Perhaps as the high dose cancer trials evolve the safety advice may change.

PAK inhibitors and potentially treating some Autism using Grandpa’s Medicine Cabinet

I wrote several posts about why PAK1 inhibitors should be beneficial in some autism and indeed some schizophrenia.

We also saw that PAK1-blocking drugs could be potentially useful for the treatment of neurofibromatosis type 2, in addition to RAS-induced cancers and neurofibromatosis type 1.

One problem with drugs developed for cancer is that, even if they finally get approved, they tend to be ultra-expensive.  Production volumes are low because even if they “work” they do not prolong life for so long and cancer has numerous sub-types.

Cheap drugs are ones used to treat common chronic conditions like high blood pressure, high cholesterol and indeed treatment of male lower urinary tract symptoms (LUTS), like benign prostatic hyperplasia (BPH).

A small number of readers of this blog have confirmed the beneficial effect of PAK inhibitors in their specific sub-types of autism.  The problem is that there are no potent PAK1 inhibitors suitable for long term use that are readily available.

The anti-parasite drug Ivermectin is an extremely cheap PAK1 inhibitor, but cannot be used long term, due to its other effects.

Propolis containing CAPE (Caffeic Acid Phenethyl Ester) is a natural PAK1 inhibitor, but may not be sufficiently potent as is reported by people with neurofibromatosis.

You would think somebody would just synthesize CAPE (Caffeic Acid Phenethyl Ester) artificially and then higher doses could be achieved.

PAK Inhibitors and Treatment of Prostate Enlargement

I was rather surprised that research has recently been published suggesting that PAK inhibitors could be used to treat the prostate enlargement, common in most older men. 

P21-Activated Kinase Inhibitors FRAX486 and IPA3: Inhibition of Prostate Stromal Cell Growth and Effects on Smooth Muscle Contraction in the Human Prostate

Abstract

Prostate smooth muscle tone and hyperplastic growth are involved in the pathophysiology and treatment of male lower urinary tract symptoms (LUTS). Available drugs are characterized by limited efficacy. Patients’ adherence is particularly low to combination therapies of 5α-reductase inhibitors and α₁-adrenoceptor antagonists, which are supposed to target contraction and growth simultaneously. Consequently, molecular etiology of benign prostatic hyperplasia (BPH) and new compounds interfering with smooth muscle contraction or growth in the prostate are of high interest. Here, we studied effects of p21-activated kinase (PAK) inhibitors (FRAX486, IPA3) in hyperplastic human prostate tissues, and in stromal cells (WPMY-1). In hyperplastic prostate tissues, PAK1, -2, -4, and -6 may be constitutively expressed in catecholaminergic neurons, while PAK1 was detected in smooth muscle and WPMY-1 cells. Neurogenic contractions of prostate strips by electric field stimulation were significantly inhibited by high concentrations of FRAX486 (30 μM) or IPA3 (300 μM), while noradrenaline- and phenylephrine-induced contractions were not affected. FRAX486 (30 μM) inhibited endothelin-1- and -2-induced contractions. In WPMY-1 cells, FRAX486 or IPA3 (24 h) induced concentration-dependent (1–10 μM) degeneration of actin filaments. This was paralleled by attenuation of proliferation rate, being observed from 1 to 10 μM FRAX486 or IPA3. Cytotoxicity of FRAX486 and IPA3 in WPMY-1 cells was time- and concentration-dependent. Stimulation of WPMY-1 cells with endothelin-1 or dihydrotestosterone, but not noradrenaline induced PAK phosphorylation, indicating PAK activation by endothelin-1. Thus, PAK inhibitors may inhibit neurogenic and endothelin-induced smooth muscle contractions in the hyperplastic human prostate, and growth of stromal cells. Targeting prostate smooth muscle contraction and stromal growth at once by a single compound is principally possible, at least under experimental conditions.

It looks like a PAK inhibitor could potentially solve both the key problems in BPH and so replace the current therapies.

Existing Drugs for LUTS/BPH

Undoubtedly someone is going to wonder whether existing drugs for LUTS/BPH might improve autism.  This is actually possible, but totally unrelated to PAK1 inhibition and RASopathies.

Existing drugs are in two classes, 5α-reductase inhibitors and α₁-adrenoceptor antagonists.

α-adrenoceptor antagonists

Alpha blockers relax certain muscles and help small blood vessels remain open. They work by keeping the hormone norepinephrine (noradrenaline) from tightening the muscles in the walls of smaller arteries and veins, which causes the vessels to remain open and relaxed. This improves blood flow and lowers blood pressure.

Because alpha blockers also relax other muscles throughout the body, these medications can help improve urine flow in older men with prostate problems.

Selective α₁-adrenergic receptor antagonists are often used in BPH because it is the α₁-adrenergic receptor that is present in the prostate.

 α ₂-adrenergic receptors are present elsewhere in the body

Alpha-2 blockers are used to treat anxiety and post-traumatic stress disorder (PTSD). They decrease sympathetic outflow from the central nervous system. Post-traumatic stress disorder is an anxiety disorder that is theorized to be related to a hyperactive sympathetic nervous system.

Alpha-2 receptor agonists for the treatment of post-traumatic stress disorder

So a nonselective alpha blocker, like one given to an older man with high blood pressure and BPH, might well have an effect on some kinds of anxiety.

You would think that a selective alpha 2 blocker might be interesting, how about Idazoxan?

Idazoxan is a drug which is used in research. It acts as both a selective α2 adrenergic receptor antagonist, and an antagonist for the imidazoline receptor. Idazoxan has been under investigation as an antidepressant, but it did not reach the market as such. More recently, it is under investigation as an adjunctive treatment in schizophrenia. Due to its alpha-2 receptor antagonism it is capable of enhancing therapeutic effects of antipsychotics, possibly by enhancing dopamine neurotransmission in the prefrontal cortex of the brain, a brain area thought to be involved in the pathogenesis of schizophrenia.

Mirtazapine is a cheap generic drug used at high doses for depression.  It happens to be a selective alpha 2 blocker, but it has numerous other effects as well.  One reader of this blog does respond very well to Mirtazapine.

So realistically in Grandpa’s medicine cabinet there might a selective alpha 1 agonist or a non-selective alpha agonist, it is the latter type that might have an effect on some kinds of autism.

5α-reductase inhibitors

The pharmacology of 5α-reductase inhibition involves the binding of NADPH to the enzyme followed by the substrate. Specific substrates include testosterone, progesterone, androstenedione, epitestosterone, cortisol, aldosterone, and deoxycorticosterone.

Beyond being a catalyst in testosterone reduction, 5α-reductase isoforms I and II reduce progesterone to 5α-dihydroprogesterone (5α-DHP) and deoxycorticosterone to dihydrodeoxycorticosterone (DHDOC).

In vitro and animal models suggest subsequent 3α-reduction of DHT, 5α-DHP and DHDOC lead to neurosteroid metabolites with effect on cerebral function.

These neurosteroids, which include allopregnanolone, tetrahydrodeoxycorticosterone (THDOC), and 5α-androstanediol, act as potent positive allosteric modulators of GABA_A receptors, and have anticonvulsant, antidepressant, anxiolytic, prosexual, and anticonvulsant effects.

Inhibition of 5α-reductase results in decreased conversion of testosterone to DHT.

This, in turn, results in slight elevations in testosterone and estradiol levels. 

In BPH, DHT acts as a potent cellular androgen and promotes prostate growth; therefore, it inhibits and alleviates symptoms of BPH. In alopecia, male and female-pattern baldness is an effect of androgenic receptor activation, so reducing levels of DHT also reduces hair loss.

A new look at the 5alpha-reductase inhibitor finasteride

Finasteride is the first 5alpha-reductase inhibitor that received clinical approval for the treatment of human benign prostatic hyperplasia (BPH) and androgenetic alopecia (male pattern hair loss). These clinical applications are based on the ability of finasteride to inhibit the Type II isoform of the 5alpha-reductase enzyme, which is the predominant form in human prostate and hair follicles, and the concomitant reduction of testosterone to dihydrotestosterone (DHT). In addition to catalyzing the rate-limiting step in the reduction of testosterone, both isoforms of the 5alpha-reductase enzyme are responsible for the reduction of progesterone and deoxycorticosterone to dihydroprogesterone (DHP) and dihydrodeoxycorticosterone (DHDOC), respectively. Recent preclinical data indicate that the subsequent 3alpha-reduction of DHT, DHP and DHDOC produces steroid metabolites with rapid non-genomic effects on brain function and behavior, primarily via an enhancement of gamma-aminobutyric acid (GABA)ergic inhibitory neurotransmission. Consistent with their ability to enhance the action of GABA at GABA(A) receptors, these steroid derivatives (termed neuroactive steroids) possess anticonvulsant, antidepressant and anxiolytic effects in addition to altering aspects of sexual- and alcohol-related behaviors. Thus, finasteride, which inhibits both isoforms of 5alpha-reductase in rodents, has been used as a tool to manipulate neuroactive steroid levels and determine the impact on behavior. Results of some preclinical studies and clinical observations with finasteride are described in this review article. The data suggest that endogenous neuroactive steroid levels may be inversely related to symptoms of premenstrual and postpartum dysphoric disorder, catamenial epilepsy, depression, and alcohol withdrawal.

This would suggest that a 5α-reductase inhibitor, like finasteride, that might be among Grandpa’s tablets might very well have an effect on someone with GABAa dysfunction, this includes very many people with autism, schizophrenia and Down Syndrome.

Whether the effect will be good or bad is hard to say, and may well depend on whether other drugs that target GABA or NMDA receptors are being used. Due to their other effects, 5α-reductase inhibitors are usually only used in adults.

Merck developed a lower dose form of finasteride, called Prospecia to treat baldness, usually in men.  It is 20% the normal potency used for BPH.

Side effects

The current BPH drugs cause side effects in some people.  PAK1 inhibitors may also have some side effects.

Conclusion

Going back in the days of living with your extended family might make treating many people’s autism much simpler.  It looks like many older people’s drugs can be repurposed for some types of autism (ion channel modifying diuretics, calcium channel blockers, statins, even potentially intranasal insulin in some).  Because older people’s drugs are so widely used they are well understood and inexpensive.  

Clearly the research on PAK inhibitors for LUTS/BPH is at an early stage, but there is a huge potential market.   A widely available PAK1 inhibitor might be a big help to some people with autism, neurofibromatosis, other RASopathies, not just Grandpa’s prostate.

In addition to FRAX486 and IPA3, why doesn’t someone try synthetic CAPE, i.e. without the bees, as a PAK inhibitor?

Bioactivity and chemical synthesis of caffeic acid phenethyl ester and its derivatives.

There is far more chance of a PAK1 inhibitor coming to market for LUTS/BPH, or certain cancers than for autism.  That is a fact of life.

As for 5α-reductase inhibitors, like finasteride, we know from Hardan’s study on Pregnenolone at Stanford that this hormone can have a positive effect and we know that various natural steroid metabolites will modulate GABA subunits.  So it is quite likely that finasteride is going have a behavioral effect.  Perhaps Hardan would like to trial finasteride 5mg and 1mg (Prospecia) in some adults with autism. I suspect it will make some people “worse” and others somewhat “better”; so please do not report the “average” response, highlight the nature of the positive responders.

Intranasal Insulin for Some Autism vs IGF-1 and NNZ-2566

 

Very often the simplest solutions are the best and very often, when fault finding a problem, people overlook the obvious.  

I seem to be forever having to mend things and I find this all the time.

Back in 2013, when I knew much less about autism, I wrote about the experimental use of insulin like growth factor 1 (IGF-1) in autism.  

It’s a Small World – IGF-1 and NNZ-2566 in Autism

It turned out that in autism the many different growth factors can be disturbed (too much, or too little) and this variation does indeed define some specific types of autism.  For example in Rett Syndrome there are very low levels of Nerve Growth Factor (NGF); low levels of NGF in some older people is the cause of their dementia.  In more common types of autism NGF is actually elevated.

IGF-1 is very well studied.

 

IGF-1 is a primary mediator of the effects of growth hormone (GH). 

Growth hormone is made in the anterior pituitary gland, is released into the blood stream, and then stimulates the liver to produce IGF-1. IGF-1 then stimulates systemic body growth, and has growth-promoting effects on almost every cell in the body, especially skeletal muscle, cartilage, bone, liver,kidney, nerves, skin, hematopoietic cell, and lungs. This would explain why adults abusing GH may end up needing hip and knee replacements.

Before getting into the science, IGF-1 has long been available as a drug to treat children with growth delays.  In the US this drug is being used on children with a type of autism called Phelan-McDermid Syndrome.

Now, regular readers will recall from my last post on intranasal insulin that it was in this very syndrome that there was a successful intranasal insulin.

So most likely without delving into the science at all it looks like IGF-1 and intranasal insulin are both options to treat the same dysfunction.

Using IGF-1

Clinical Trial in 22q13 Deletion Syndrome (Phelan-McDermid Syndrome)

Using Intranasal Insulin

Intranasal insulin to improve developmental delay in children with 22q13 deletion syndrome: an exploratory clinical trial.

NNZ-2566

This is an Australian drug that is a modified version of IGF-1 (a so called analog).  They modified it so that it can be taken orally rather than by injection.  The developer has a very thorough presentation showing why they think it should be effective in autism.  

  

NNZ-2566 - Rationale for use in Autistic Spectrum Disorders

The Science

The first thing to note is that insulin and IGF-1 act as messengers.  Disruption in growth factor signaling can have serious consequences.

Insulin and IGF-1 both activate the same insulin receptor (IR).

Most people think that insulin is a just a hormone produced in their pancreas that regulates the amount of glucose (sugar) in their blood.  It does of course do that, but it actually does much more.

  

Insulin receptors are expressed all over the body including the brain.

Here is a relatively simple presentation explaining the role of insulin signaling in the brain:-

The role of insulin receptor signaling in the brain

Now for the diehard scientists among you that have been reading about all those signaling pathways that lie behind autism, cancer and many other hard to treat conditions, look at the graphic below.

We know the importance of RAS.  Impaired RAS signaling underlies the RASopathies, one feature of which is cognitive loss (MR/ID), another is autism.

We also know the importance of Akt (PKB/protein kinase B) in some types of autism.  PTEN appears again.

So irrespective of an undoubtedly important effect on glucose and insulin resistance, we should expect activation of insulin receptors in the brain, in some types of autism, to have a further positive effect.

It would seem to be a potential therapy for RASopathies.

As is often the case, there are extreme dysfunctions of RAS and I suggest there are more mild dysfunctions.

I suggest that some people with autism and some cognitive dysfunction have a partial RASopathy.

Since autism contains both extremes of many dysfunctions, there will undoubtedly be types of autism that respond negatively, or not at all, to activation of insulin receptors in the brain.

Practicalities

Nobody likes injections and that is necessary to give IGF-1.

NNZ-2566 is an experimental autism drug and on past performance that means it will take decades to reach the market, if ever.

That leaves insulin which was sitting all along in your local pharmacy.

Intranasal insulin was once investigated for use in diabetics, but it did not work.  It is not absorbed into the blood stream.

This is of course the huge advantage for people with autism, since we only want to activate the insulin receptors in the brain.  If you are not diabetic why would you want to have any effects in the rest of the body?

Indeed there are known major side effects of injecting IGF-1 or GH (growth hormone) into adults.  All kinds of things start growing and this can lead to terrible results.

The fact that all the studies show that intranasal insulin does not enter the blood stream and so lower blood glucose levels, makes it a much better drug for autism than IGF-1 or indeed NNZ-2566.

Insulin

There are various types of insulin and the main difference is that some are modified to be longer acting.

The basic insulin is soluble or clear insulin, and nowadays is synthetic rather than derived from pigs.  Examples include Humulin Regular/R/S by Lilly.

The standard concentration is 100 IU/ml.

The trials in Alzheimer’s and other conditions varied in dosage but generally used about 20 to 40 IU per day.

This is not a trivial dose.  If injected, rather than inhaled, that dose would have a significant effect on lowering blood sugar and would be dangerous.

My antihistamine nasal spray gives a metered dose of 0.14 ml.

So without any dilution, if filled with off the shelf insulin it would dispense 14 IU per spray.

So no special high tech drugs, dilutants/diluents or dispensers appear to be necessary. Some trials do use fancy inhalers, like the one in the video at the end of this post.

To be prudent it might be wise to dilute the insulin so as to gradually increase the dose.  Maybe in some people the nasal membrane is more permeable than in others.  Some of the trials did this, but most did not.

A fridge is required, because insulin needs to be kept chilled.

I do wonder why nobody seems to be researching this in autism.  Silly point, as one insulin researcher commented on the earlier post; there is no big money to be made, hence no interest.

Insulin & Alzheimer’s

The reasons that intranasal insulin improves Alzheimer’s, and likely will Down Syndrome, may differ to those help in (some) autism.

Beta amyloid is key to Alzheimer’s (and early onset Alzheimer’s in Down Syndrome) but is not a known issue in autism.  Central insulin resistance is an issue in Alzheimer’s and might well be in autism.  

Perhaps people with mitochondrial dysfunction (an energy conversion dysfunction) might particularly benefit from increased glucose uptake in the brain.  It appears that mitochondrial dysfunction plays a role in insulin resistance. 

Role of Mitochondrial Dysfunction in Insulin Resistance

The activation of the RAS pathway might be highly beneficial to some people with autism.  

Here is a good film, which refers to the studies from previous posts and shows the effect on one man with Alzheimer's. 

Insulin and Alzheimer's (approx. 22 min.)

 You also see their fancy inhaler device.

Has anyone tried Cinnamon (or Sodium Benzoate) for Autism?

I have written several posts about Cinnamon and its metabolite Sodium Benzoate. I know that some readers are now using it for its cholesterol lowering and insulin sensitivity improving properties that were shown in the clinical trials I highlighted.

Cinnamon and DJ-1 as a general Anti-Oxidant and perhaps Much More

Is DJ-1 expression negatively associated with severity of Autism? If so, Sodium Benzoate (Cinnamon) may well be beneficial

Sodium benzoate (Cinnamon) trialed for Schizophrenia (Adult-onset Autism)

NMDAR hypo-function causing E/I imbalance in Autism and Schizophrenia – Baclofen, Sodium benzoate and Cinnamon (again)

But has anyone tried it for autism?

The first time I wrote about it I did acquire a big bag of the correct variety (Cinnamomum verum or Ceylon Cinnamon) and also a bag of the very high flavanol (epicatechin) cocoa.  My cinnamon trial was limited to seeing what it looked/tasted like when added to the Polypill concoction Monty, aged 12 with ASD, drinks at breakfast.  It was rather like adding a teaspoonful of fine sand, so not much “testing” took place.

Now that Monty has shown an ability, and even enjoyment, for pill swallowing, things are much simpler.  The cinnamon can be put inside gelatin capsules; it’s a little messy, but no great trouble.

Having recently been researching about the gene enhancers and silencers, which are controlled by the 95% of your DNA that rarely gets studied (the exome is the part everyone studies and some people test for abnormalities), it did occur to me that I already have two safe substances, that I have both researched and acquired, which have a gene expression enhancing effect.

Cinnamon “Experiment”

Even though summer is the wrong time to test anything in Monty, aged 12 with ASD, since his pollen allergy triggers a regression, I decided to make a trial.  I have 1 kg of this special cinnamon, and so it’s not like I need to ration it.

I gave about 2.5ml of cinnamon split into three daily doses using some gelatin capsules that used to be full of another supplement (choline).

Results so far:-

Complete absence of summertime bad behaviors, which are already 90% subdued by Verapamil, but do sometimes present themselves.

Interesting behavioral developments:- 

·        Like many people with autism, Monty likes order.  So turn off lights, shut doors, wash dirty hands etc.  The latest surprise was that when I took something from the rear of my car and he shut the tail gate (boot). Given the size of my car, for someone of his small stature, this is quite an achievement, since he really has to stretch on his toes.  This is the first time he has ever done this and now he does it every time.

·        Monty can brush his teeth and get dressed, but his clothes are sitting there on his bed.  The other day when told to go upstairs and brush his teeth, he returned fully clothed, having chosen/found his clothes all by himself.

·        On awakening, sometimes Monty might say “can I have a glass of water”, to which he might be told go downstairs and get water, and usually someone would go down with him.  Recently I find him in the early morning sitting at the kitchen table playing on his iPad with the glass of water he served himself with.

·        Piano playing also seems to be going very well, indeed on Wednesday after his piano lesson the teacher started telling me that she has taught 73 children with autism and never has she had someone start at his beginning level and progress so far.  This is clearly not down to cinnamon (it was greatly helped by bumetanide, atorvastatin and NAC), but why is she telling me this now, after over three years of lessons?

·        Speech for people with Classic autism, even when it develops, is always a little odd, reading a book out loud or singing does not mean you can speak.  It is as if the mother tongue is a foreign language and needs to be translated in your head. So for me it would be like speaking German.  It is my fourth language, I know lots of words, but I cannot think in German.

Many people with autism like to know their schedule. Today Monty was going to go swimming, amongst other things, but a change of plan meant we had gone to eat.  So I said to Monty “I am too full to go swimming, we will go later”.

A few minutes later as I stopped the car, Monty says “swimming when Dad feels better”.

There is nothing super clever in that statement, but it is not the sort of unprompted comment I usually get to hear for son number two.

These are all little steps and may be coincidental, but normally with Monty things go backwards in summer.  Even effective interventions appear to lose their effectiveness. 

I still keep an open mind on cinnamon, but I did just order a big bag of empty gelatin capsules.

Anybody else tried Cinnamon?

It would be useful to know from people who found that Bumetanide or Sulforaphane were effective for autism, whether cinnamon also has a positive effect.

There are several reasons why it may help:-

·        Change in NMDA signaling, affecting the excitatory/inhibitory balance

·        Affects gene expression related to oxidative stress (why cinnamon helps reduce cholesterol and improve insulin sensitivity)

·        Increases BDNF, Brain-derived neurotrophic factor  (aka “brain fertilizer”)

·        NaB (sodium benzoate) reduces Microglial and Astroglial Inflammatory Responses

·        NaB exerts its anti-inflammatory effect through the inhibition of NF-κB

·        NaB suppresses the activation of p21^ras in microglia

·        NaB can also regulate many immune signaling pathways responsible for inflammation, glial cell activation, switching of T-helper cells, modulation of regulatory T cells

NF-κB is the master regulator of inflammation in the same way that Nrf 2 is for oxidative stress.

Incorrect regulation of NF-κB has been linked to cancer, inflammatory, and autoimmune diseases, septic shock, viral infection, and improper immune development. NF-κB has also been implicated in processes of synaptic plasticity and memory

In autism it seems that we want to activate Nrf2 but to inhibit NF-κB.  Safely inhibiting NF-κB is the Holy Grail for many diseases.

We covered RAS in earlier posts.  The RAS protein is abnormally active in cancer.

So called RASopathies are developmental syndromes caused by mutations in genes that alter the Ras subfamily.  RASopathies are often associated with autistic symptoms and/or intellectual disability/mental retardation.

Common inhibitors of RAS are statins and Farnesyltransferase inhibitors.  Most Farnesyltransferase inhibitors are expensive cancer research drugs, but one is gingerol.

Since statins do very clearly improve the autism of Monty, aged 12 with ASD, I did try adding gingerol as my “Statin plus” therapy.  At the dose I used there was no noticeable effect.

However, I now learn that “NaB suppressed the activation of p21^ras in microglia”.  P21, RAS, and p21^ras are different names for the same protein.  So it would seem that NaB is therefore a RAS inhibitor and perhaps a more potent one than gingerol.

   

Too much BDNF, just like too much lawn fertilizer, may not be a good thing.

BDNF is low in schizophrenia, but is thought to be elevated in “most” autism.

   

Sodium Benzoate, a Metabolite of Cinnamon and a Food Additive, Reduces Microglial and Astroglial Inflammatory Responses

 Abstract

Upon activation, microglia and astrocytes produce a number of proinflammatory molecules that participate in the pathophysiology of several neurodegenerative disorders. This study explores the anti-inflammatory property of cinnamon metabolite sodium benzoate (NaB) in microglia and astrocytes. NaB, but not sodium formate, was found to inhibit LPS-induced expression of inducible NO synthase (iNOS), proinflammatory cytokines (TNF-α and IL-1β) and surface markers (CD11b, CD11c, and CD68) in mouse microglia. Similarly, NaB also inhibited fibrillar amyloid β (Aβ)-, prion peptide-, double-stranded RNA (polyinosinic-polycytidylic acid)-, HIV-1 Tat-, 1-methyl-4-phenylpyridinium⁺-, IL-1β-, and IL-12 p40₂-induced microglial expression of iNOS. In addition to microglia, NaB also suppressed the expression of iNOS in mouse peritoneal macrophages and primary human astrocytes. Inhibition of NF-κB activation by NaB suggests that NaB exerts its anti-inflammatory effect through the inhibition of NF-κB. Although NaB reduced the level of cholesterol in vivo in mice, reversal of the inhibitory effect of NaB on iNOS expression, and NF-κB activation by hydroxymethylglutaryl-CoA, mevalonate, and farnesyl pyrophosphate, but not cholesterol and ubiquinone, suggests that depletion of intermediates, but not end products, of the mevalonate pathway is involved in the anti-inflammatory effect of NaB. Furthermore, we demonstrate that an inhibitor of p21^ras farnesyl protein transferase suppressed the expression of iNOS, that activation of p21^ras alone was sufficient to induce the expression of iNOS, and that NaB suppressed the activation of p21^ras in microglia. These results highlight a novel anti-inflammatory role of NaB via modulation of the mevalonate pathway and p21^ras.

  

Immunomodulation of experimental allergic encephalomyelitis by cinnamon metabolite sodium benzoate.

ABSTRACT Experimental allergic encephalomyelitis (EAE) is an animal model of multiple sclerosis (MS), the most common human demyelinating disease of the central nervous system. Sodium benzoate (NaB), a metabolite of cinnamon and a FDA-approved drug against urea cycle disorders in children, is a widely used food additive, which is long known for its microbicidal effect. However, recent studies reveal that apart from its microbicidal effects, NaB can also regulate many immune signaling pathways responsible for inflammation, glial cell activation, switching of T-helper cells, modulation of regulatory T cells, cell-to-cell contact, and migration. As a result, NaB alters the neuroimmunology of EAE and ameliorates the disease process of EAE. In this review, we have made an honest attempt to analyze these newly-discovered immunomodulatory activities of NaB and associated mechanisms that may help in considering this drug for various inflammatory human disorders including MS as primary or adjunct therapy.

Conclusion

Rather to my surprise, Cinnamon does seem to have a noticeable cognitive effect in the type of autism I am interested in.  It appears, rather like the statin, to promote improved adaptive behavior by reducing inhibition and increasing spontaneous thought and actual decision making.

Of all the many possible modes of action, I am thinking that inhibition of NF-κB and/ or RAS inhibition are most likely since the effect is very similar to that produced by the statin.

I will certainly continue with cinnamon and when my size 000 gelatin capsules arrive, I will look at different doses.  Currently the dose is about 2.5 ml split three times a day, using size 00 gelatin capsules.