Immune modulatory treatments for autism spectrum disorder

Need a wizard, or your local doctor?

I was intrigued to come across a recent paper on immune modulatory treatments for autism by a couple of doctors from Massachusetts General Hospital for Children.  The lead author has interests in:

·      Autism spectrum disorders

·      Psychopharmacology

·      Developmental Disabilities

·      Williams syndrome

·      Angelman syndrome

·      Down syndrome

Apparently, he is an internationally-recognized expert in the neurobiology and neuropsychopharmacology of childhood-onset neuropsychiatric disorders including autistic disorder.  Sounds promising, hopefully we will learn something new.

The paper is actually a review of existing drugs, with immunomodulatory properties, that have already been suggested to be repurposed for autism. The abstract was not very insightful, so I have highlighted the final conclusions and listed the drugs, by category, that they thought should be investigated further.

All the drugs have already been covered in this blog and have already been researched in autism.

One important point raised in the conclusion relates to when the drugs are used.  Autism is a progressive condition early in life and there are so-called “critical periods” when the developing brain is highly vulnerable.

For example, Pentoxifylline has been found to be most effective in very young children.  This does not mean do not give it to a teenager with autism, it just means the sooner you treat autism the better the result will be.  This is entirely logical.

Some very clever drugs clearly do not work if given too late, for example Rapamycin analogs used in people with TSC-type autism.

Multiple Critical Periods for Rapamycin Treatment to Correct Structural Defects in Tsc-1-Suppressed Brain

Importantly, each of these developmental abnormalities that are caused by enhanced mTOR pathway has a specific window of opportunity to respond to rapamycin. Namely, dyslamination must be corrected during neurogenesis, and postnatal rapamycin treatment will not correct the cortical malformation. Similarly, exuberant branching of basal dendrites is rectifiable only during the first 2 weeks postnatally while an increase in spine density responds to rapamycin treatment thereafter.  

Back to today’s paper.

Immune modulatory treatments for autism spectrum disorder

The identification of immune dysregulation in at least a subtype ASD has led to the hypothesis that immune modulatory treatments may be effective in treating the core and associated symptoms of ASD. In this article, we discussed how currently FDA-approved medications for ASD have immune modulatory properties.

“Risperidone also inhibited the expression of inflammatory signaling proteins, myelin basic protein isoform 3 (MBP1) and mitogen-activated kinase 1 (MAPK1), in a rat model of MIA. Similarly, aripiprazole has been demonstrated to inhibit expression of IL-6 and TNF-α in cultured primary human peripheral blood mononuclear cells from healthy adult donors.”

We then described emerging treatments for ASD which have been repurposed from nonpsychiatric fields of medicine including metabolic disease, infectious disease, gastroenterology, neurology, and regenerative medicine, all with immune modulatory potential. Although immune modulatory treatments are not currently the standard of care for ASD, remain experimental, and require further research to demonstrate clear safety, tolerability, and efficacy, the early positive results described above warrant further research in the context of IRB-approved clinical trials. Future research is needed to determine whether immune modulatory treatments will affect underlying pathophysiological processes affecting both the behavioral symptoms and the common immune-mediated medical co-morbidities of ASD. Identification of neuroimaging or inflammatory biomarkers that respond to immune modulatory treatment and correlate with treatment response would further support the hypothesis of an immune-mediated subtype of ASD and aid in measuring response to immune modulatory treatments. In addition, it will be important to determine if particular immune modulating treatments are best tolerated and most effective when administered at specific developmental time points across the lifespan of individuals with ASD.

Here are the drugs they listed:-

1.     Metabolic disease

Spironolactone

Pioglitazone

Pentoxifylline

Spironolactone is a cheap potassium sparing diuretic. It has secondary effects that include reducing the level of male hormones and some inflammatory cytokines.

Pioglitazone is drug for type 2 diabetes that improves insulin sensitivity.  It reduces certain inflammatory cytokines making it both an autism therapy and indeed a suggested Covid-19 therapy.

Pentoxifylline is a non-selective phosphodiesterase (PDE) inhibitor, used to treat muscle pain.  PDE inhibitors are very interesting drugs with a great therapeutic potential for the treatment of immune-mediated and inflammatory diseases.  Roflumilast and Ibudilast are PDE4 inhibitors that also may improve some autism.  The limiting side effect can be nausea/vomiting, which can happen with non-selective PDE4 inhibitors.

I did try Spironolactone once; it did not seem to have any effect.  It is a good match for bumetanide because it increases potassium levels.

I do think that Pioglitazone has a helpful effect and there will be another post on that.

PDE inhibitors are used by readers of this blog. Maja is a fan of Pentoxifylline, without any side effects. Roflumilast at a low dose is supposed to raise IQ, but still makes some people want to vomit. The Japanese drug Ibudilast works for some, but nausea is listed as a possible side effect.

2.     Infectious disease

Minocycline

Vancomycin

Suramin

Minocycline is an antibiotic that crosses in to the brain.  It is known to stabilize activated microglia, the brain’s immune cells.  It is also known that tetracycline antibiotics are immunomodulatory.

Vancomycin is an antibiotic used to treat bacterial infections, if taken orally it does not go beyond the gut.  It will reduce the level of certain harmful bacteria including Clostridium difficile.

Suramin is an anti-parasite drug that Dr Naviaux is repurposing for autism, based on his theory of cell danger response.

  

3.     Neurology

Valproic acid

Valproic acid is an anti-epileptic drug.  It also has immunomodulatory and HDAC effects, these effects can both cause autism when taken by a pregnant mother and also improve autism in some people.

Valproic acid can have side effects. Low dose valproic acid seems to work for some people. 

4.     Gastroenterology

Fecal microbiota transplant (FMT)

FMT is currently used to treat recurrent Clostridium difficile infection and may also be of benefit for other GI conditions including IBD, obesity, metabolic syndrome, and functional GI disorders.

Altered gut bacteria (dysbiosis) is a feature of some autism which then impairs brain function.  Reversing the dysbiosis with FMT improves brain function.  

5.     Oncology

Lenalidomide

Romidepsin

  

Lenalidomide is an expensive anti-cancer drug that also has immunomodulatory effects.

Romidepsin is a potent HDAC inhibitor, making it a useful cancer therapy.  HDAC inhibitors are potential autism drugs, but only if given early enough not to miss the critical periods of brain development. 

6.     Pulmonology

N-acetylcysteine

Many people with autism respond well to NAC. You do need a lot of it, because it has a short half-life.

7.     Nutritional medicine and dietary supplements

Omega-3 fatty acids

Vitamin D

Flavonoids

Nutritional supplements can get very expensive.  In hot climates, like Egypt, some dark skinned people cover up and then lack vitamin D.  A lack of vitamin D will make autism worse.

Some people with mild brain disorders do seem to benefit from some omega-3 therapies.

Flavonoids are very good for general health, but seem to lack potency for treating brain disorders.  Quercetin and luteolin do have some benefits. 

8.     Rheumatology

Celecoxib

Corticosteroids

Intravenous immunoglobulin (IVIG)

Celecoxib is a common NSAID that is particularly well tolerated (it affects COX-2 and only marginally COX-1, hence its reduced GI side effects).

NSAIDS are used by many people with autism.

Steroids do improve some people’s autism, but are unsuitable for long term use.  A short course of steroids reduces Covid-19 deaths – a very cost effective therapy.

IVIG is extremely expensive, but it does provide a benefit in some cases. IVIG is used quite often to treat autism in the US, but rarely elsewhere other than for PANS/PANDAS that might occur with autism.

9.     Regenerative medicine

Stem cell therapy

I was surprised they gave stem cell therapy a mention. I think it is still early days for stem cell therapy.

Conclusion

I have observed the ongoing Covid-19 situation with interest and in particular what use has been made of the scientific literature.

There are all sorts of interesting snippets of data. You do not want to be deficient in Zinc or vitamin D, having high cholesterol will make it easier for the virus to enter your cells.  Potassium levels may plummet and blood becomes sticky, so may form dangerous clots. A long list of drugs may be at least partially effective, meaning they speed up recovery and reduce death rates. Polytherapy, meaning taking multiple drugs, is likely to be the best choice for Covid-19.

Potential side effects of some drugs have been grossly exaggerated, as with drugs repurposed for autism.  Even in published research, people cheat and falsify the data. In the case of hydroxychloroquine, the falsified papers were quickly retracted.

The media twist the facts, to suit their narrative, as with autism.  This happens even with Covid-19. Anti-Trump media (CNN, BBC etc) is automatically anti-hydroxychloroquine, and ignores all the published research and the results achieved in countries that widely use it (small countries like China and India). 

Shutting down entire economies when only 5-10% of the population have been infected and hopefully got some immunity, does not look so smart if you are then going to reopen and let young people loose.  They will inevitably catch the virus and then infect everyone else. Permanent lockdown restrictions, if followed by everyone, until a vaccine which everyone actually agreed to take, makes sense and living with the virus makes sense, but anything in between is not going to work. After 3 months without any broad lockdown, and allowing young people to socialize, most people would have had the virus and then those people choosing to shield could safely reemerge. The death rate with the current optimal, inexpensive treatment, as used in India or South Africa is very low, in people who are not frail to start with. Time to make a choice.  Poor people in poor countries cannot afford to keep going into lockdown, they need to eat.

What hope is there for treating a highly heterogeneous condition like autism, if it is not approached entirely rationally and without preconceptions and preconditions?  In a pandemic we see that science does not drive policy and translating science into therapy is highly variable.  The science is there for those who choose to read it.

I frequently see comments from parents who have seen some of the research showing that autism has an inflammatory/auto-immune component.  They ask why this has not been followed up on in the research.  It has been followed up on.  It just has not been acted upon.

Why has it not been acted on?

This missing stage is called “translation”.  Why don’t doctors translate scientific findings into therapy for their patients?

What is common sense to some, is “experimental” to others. “Experimental” is frowned upon in modern medicine, but innovation requires experimentation.

Many people’s severe autism is unique and experimental polytherapy/polypharmacy is their only hope.

The cookie cutter approach is not going to work for autism. 

Thankfully, for many common diseases the cookie cutter approach works just fine.

Do the authors of today’s paper, Dr McDougle and Dr Thom, actually prescribe to their young patients many of the drugs that they have written about?  I doubt it and therein lies the problem.  

Time for that wizard, perhaps? 

A few years ago I did add the following tag line, under the big Epiphany at the top of the page. 

An Alternative Reality for Classic Autism - Based on Today's Science

You can choose a different Autism reality, if you do not like your current one.  I am glad I did. I didn't even need a wizard.  

There are many immuno-modulatory therapies for autism that the Massachusetts doctor duo did not mention, but it is good that they made a start.

Take your Bumetanide Studies with a Pinch of Salt

This blog does try to be based on evidence, but sometimes you do have to question the validity of what appears in peer reviewed journals.  It might concern what does, or does not cross the blood brain barrier, or what works in vivo versus in vitro.

Two interesting papers were recently brought to my attention regarding Bumetanide.

With a pinch of salt is an English idiom which means

to view something with skepticism 

In Tyler’s paper it was rats with epilepsy showing big improvements when taking Bumetanide. 

In Agnieszka’s paper, involving mice and Chinese hamsters, researchers are making the point that so little Bumetanide crosses into the brain that its therapeutic value is limited. 

So which is true? 

Well it seems that in some humans with autism enough bumetanide crosses the blood brain barrier (BBB) to show a positive effect.  Perhaps if a more penetrative analogue of Bumetanide was developed, it would show even greater effect, otherwise adjunct therapies may be needed (Acetazolamide, potassium bromide, estradiol etc) to gain the full benefit of lowering intracellular chloride. 

In the past I have made the case for bumetanide possibly reducing the incidence of epilepsy developing in autism and that this really would be important. This does not mean that one person with autism might not develop epilepsy around the same time he started taking bumetanide. In the study below the rats with seizures seemed to be protected by bumetanide and the number of harmful neural connections detected in the brain was significantly reduced. 

Multiple blood-brain barrier transport mechanisms limit bumetanide accumulation, and therapeutic potential, in the mammalian brain.

Abstract

There is accumulating evidence that bumetanide, which has been used over decades as a potent loop diuretic, also exerts effects on brain disorders, including autism, neonatal seizures, and epilepsy, which are not related to its effects on the kidney but rather mediated by inhibition of the neuronal Na-K-Cl cotransporter isoform NKCC1. However, following systemic administration, brain levels of bumetanide are typically below those needed to inhibit NKCC1, which critically limits its clinical use for treating brain disorders. Recently, active efflux transport at the blood-brain barrier (BBB) has been suggested as a process involved in the low brain:plasma ratio of bumetanide, but it is presently not clear which transporters are involved. Understanding the processes explaining the poor brain penetration of bumetanide is needed for developing strategies to improve the brain delivery of this drug. In the present study, we administered probenecid and more selective inhibitors of active transport carriers at the BBB directly into the brain of mice to minimize the contribution of peripheral effects on the brain penetration of bumetanide. Furthermore, in vitro experiments with mouse organic anion transporter 3 (Oat3)-overexpressing Chinese hamster ovary cells were performed to study the interaction of bumetanide, bumetanide derivatives, and several known inhibitors of Oats on Oat3-mediated transport. The in vivo experiments demonstrated that the uptake and efflux of bumetanide at the BBB is much more complex than previously thought. It seems that both restricted passive diffusion and active efflux transport, mediated by Oat3 but also organic anion-transporting polypeptide (Oatp) Oatp1a4 and multidrug resistance protein 4 explain the extremely low brain concentrations that are achieved after systemic administration of bumetanide, limiting the use of this drug for targeting abnormal expression of neuronal NKCC1 in brain diseases.

  

New mech­an­ism un­der­ly­ing epi­lepsy found

Prolonged epileptic seizures may cause serious problems that will continue for the rest of a patient's life. As a result of a seizure, neural connections of the brain may be rewired in an incorrect way. This may result in seizures that are difficult to control with medication. Mechanisms underlying this phenomenon are not entirely known, which makes current therapies ineffective in some patients.

A study conducted with a rat epilepsy model at the Neuroscience Center of the University of Helsinki showed that a change in the function of gamma-aminobutyric acid (GABA), a main neurotransmitter in the brain, is an underlying cause in the creation of harmful neural connections.

After a prolonged convulsive seizure, instead of the usual inhibitory effect of the transmitter, GABA accelerates brain activity. This, in turn, creates new, harmful neural connections, says Research Director Claudio Rivera.

The accelerating effect of GABA was blocked for three days with a drug called bumetanide given soon after a seizure. Two months after the seizure, the number of harmful connections detected in the brain was significantly lower.

"Most importantly, the number of convulsive seizures diminished markedly," says Claudio Rivera.

In this study, new indications may be found for bumetanide in the treatment of epilepsy. Bumetanide is a diuretic already in clinical use. Extensive clinical studies have already been conducted with bumetanide regarding its ability to reduce the amount of convulsions or prevent them entirely in the acute phase of seizures. This, however, is the first time that bumetanide has been found to have a long-term effect on the neural network structure of the brain.

Further study of the newly found mechanism may eventually help limit the exacerbation of epilepsy and prevent the onset of permanent epilepsy after an individual serious seizure. It may also be possible that a similar mechanism is responsible for the onset of epilepsy after a traumatic brain injury.

"The next step is to study bumetanide both by itself and in combination with other clinically used drugs. We want to find out the ways in which it may offer additional benefits in the treatment of epilepsy in combination with and even in place of currently used antiepileptic drugs," says Claudio Rivera.

Vitamin D and Autism

Two medical readers of this blog highlighted this recent paper showing an apparent universal benefit of vitamin D supplementation in autism.

Is it too good to be true?  Time for the pinch of salt?

One important point to note is that this study was in Egypt and, although sunny, are children there eating food that has already been fortified with vitamin D, like it is in Western countries?

Randomized controlled trial of vitamin D supplementation in children with autism spectrum disorder

Abstract

BACKGROUND:

Autism spectrum disorder (ASD) is a frequent developmental disorder characterized by pervasive deficits in social interaction, impairment in verbal and nonverbal communication, and stereotyped patterns of interests and activities. It has been previously reported that there is vitamin D deficiency in autistic children; however, there is a lack of randomized controlled trials of vitamin D supplementation in ASD children.

METHODS:

This study is a double-blinded, randomized clinical trial (RCT) that was conducted on 109 children with ASD (85 boys and 24 girls; aged 3-10 years). The aim of this study was to assess the effects of vitamin D supplementation on the core symptoms of autism in children. ASD patients were randomized to receive vitamin D3 or placebo for 4 months. The serum levels of 25-hydroxycholecalciferol (25 (OH)D) were measured at the beginning and at the end of the study. The autism severity and social maturity of the children were assessed by the Childhood Autism Rating Scale (CARS), Aberrant Behavior Checklist (ABC), Social Responsiveness Scale (SRS), and the Autism Treatment Evaluation Checklist (ATEC).

RESULTS:

Supplementation of vitamin D was well tolerated by the ASD children. The daily doses used in the therapy group was 300 IU vitamin D3/kg/day, not to exceed 5,000 IU/day. The autism symptoms of the children improved significantly, following 4-month vitamin D3 supplementation, but not in the placebo group. This study demonstrates the efficacy and tolerability of high doses of vitamin D3 in children with ASD.

CONCLUSIONS:

This study is the first double-blinded RCT proving the efficacy of vitamin D3 in ASD patients. Depending on the parameters measured in the study, oral vitamin D supplementation may safely improve signs and symptoms of ASD and could be recommended for children with ASD. At this stage, this study is a single RCT with a small number of patients, and a great deal of additional wide-scale studies are needed to critically validate the efficacy of vitamin D in ASD.

Conclusion

Take your research with a pinch of salt.

Vitamin A (and ATRA) Upregulate Oxytocin via CD38

 A familiar site to Maja, the confluence of the Sava and the Danube

Today’s post is to document an interesting discovery by Maja, one reader of this blog.  She is just ahead of some Korean researchers, who very recently published a paper in Experimental Neurobiology on the same subject.

Maja noticed that giving a small dose of fish oil produced the same benefits as those often claimed for Oxytocin; she then did some investigation and noted that an enzyme called CD38 upregulates oxytocin in the brain.  The level of CD38 is affected by inflammatory cytokines and certain vitamins.  In particular, all-trans retinoic acid (ATRA) increases CD38. All-trans retinoic acid (ATRA) is made in the body from vitamin A.  ATRA is also called vitamin A acid.

Maja suggested this paper:-

All-trans Retinoic Acid Upregulates Reduced CD38 Transcription in Lymphoblastoid Cell Lines from Autism Spectrum Disorder

Deficits in social behavior in mice lacking the CD38 gene have been attributed to impaired secretion of oxytocin. In humans, similar deficits in social behavior are associated with autistic spectrum disorder (ASD), for which genetic variants of CD38 have been pinpointed as provisional risk factors. We sought to explore, in an in vitro model, the feasibility of the theory that restoring the level of CD38 in ASD patients could be of potential clinical benefit. CD38 transcription is highly sensitive to several cytokines and vitamins. One of these, all-trans retinoic acid (ATRA), a known inducer of CD38, was added during cell culture and tested on a large sample of N = 120 lymphoblastoid cell (LBC) lines from ASD patients and their parents. Analysis of CD38 mRNA levels shows that ATRA has an upmodulatory potential on LBC derived from ASD patients as well as from their parents. The next crucial issue addressed in our study was the relationship between levels of CD38 expression and psychological parameters. The results obtained indicate a positive correlation between CD38 expression levels and patient scores on the Vineland Adaptive Behavior Scale. In addition, analysis of the role of genetic polymorphisms in the dynamics of the molecule revealed that the genotype of a single-nucleotide polymorphism (rs6449182; C>G variation) in the CpG island of intron 1, harboring the retinoic-acid response element, exerts differential roles in CD38 expression in ASD and in parental LBC. In conclusion, our results provide an empirical basis for the development of a pharmacological ASD treatment strategy based on retinoids.

In December some Korean researchers also suggested that ATRA might be used therapeutically to increase Oxytocin.  Maja discovered that vitamin A can also be used, which makes sense.

The Korean paper reviews the existing literature and clinical trials on oxytocin in autism, and I suggest those interested should read it.

Some people clearly benefit from oxytocin, some do not and some suffer side effects.

In those that benefit from oxytocin, it might be simpler to upregulate the body’s own oxytocin via ATRA, or vitamin A.

Is this proof?

Of course there are other explanations possible for what Maja has noted.  She was using fish oil as a source of vitamin A, so it could be related to the other constituents.

However, I for one think it is highly plausible and does fit nicely with the ideas put forward by the Korean researchers and the earlier paper.

Vitamin A for all?

We know that autism genes include many for oxytocin, oxytocin receptors and indeed CD38, so anyone with those genes dysfunctional might benefit.

However, as we saw with biotin, more people may be affected to a lesser degree.

CD38 affects oxytocin secretion in the brain and CD38 is affected by inflammatory cytokines, so at times of elevated cytokine expression, CD38 and oxytocin might be reduced in people with no relevant genetic dysfunction.

You can have too much vitamin A, this is called Hypervitaminosis A.  You cannot suffer this condition by eating fruit and vegetables, but you can by eating too much preformed vitamin A from foods (such as fish or animal liver), supplements, or prescription medications; it can be prevented by ingesting no more than the recommended daily amount.

High intake of provitamin carotenoids (such as beta carotene) from vegetables and fruits does not cause Hypervitaminosis A, as conversion from carotenoids to the active form of vitamin A is regulated by the body to maintain an optimum level of the vitamin. Carotenoids themselves cannot produce toxicity.

So, too much cod liver oil can be bad for you, but you can eat carrots like Bugs Bunny and do no harm.  If you really overdo it, your skin may change colour to orange, something called carotenosis

You can buy vitamin A supplements as the preformed vitamin or as beta carotene.

Too much of a good thing?

In times gone by, children used to be given a tablespoon of cod liver oil daily, as a good source of vitamin D and vitamin A.  These days that amount of both vitamins would be seen as excessive.  Excess of both vitamins is bad for you, but easy to achieve, by accident, while trying to do a good thing.

Maja’s Dose

Maja achieved her positive results with a modest dose of fish oil (using 40% of one capsule) giving 3-4000 IU of vitamin A.

This is actually quite a high dose of vitamin A, if you look at the maximum safe dose.

I think many people are giving kids with autism much larger doses of fish oil and thus far too much vitamin A and D.  This has been raised as an issue by Seth, another reader of this blog.

CD38

CD38 has many other functions other than regulating oxytocin. In people who have an oxytocin dysfunction due to an upstrean CD38 dysfunction, correcting the lack of CD38 might be particularly beneficial.   

CD38 is used as a prognostic biomarker for leukemia.  This is a complex area of science.  In essence, it is an accepted fact that increased CD38 expression is associated with favorable prognosis in adult acute leukemia.

Leukemia is associated with Down Syndrome. 

Not surprisingly, both vitamin A and ATRA can be beneficial in treating leukemia.

ATRA (All Trans-Retinoic Acid) for acute myeloid leukaemia (AML)

CD38 expression is apparently easy to measure.

Perhaps in those numerous oxytocin trials for autism, they might want to bother measuring CD38?

The Recent Korean Paper

Here is what the Koreans have to say about Oxytocin:-

 Is Oxytocin Application for Autism Spectrum Disorder Evidence-Based?

CD38 is a transmembrane antigen that has been studied as a negative prognostic marker for chronic lymphocytic leukemia [72]. CD38 participates in the oxytocin secretion in the brain and affects maternal nurturing and social behavior [73]. Plasma levels of oxytocin are strongly reduced in CD38 knockout mice (CD38-/-mice) and subcutaneous oxytocin injection or lentiviralvector-mediated delivery of human CD38 into the hypothalamus rescued social memory and maternal care in these mice [73].

CD38 transcription is highly sensitive to cytokines and vitamins, including all-trans retinoic acid (ATRA), a known inducer of CD38 [75]. In a study on lymphoblastoid cell lines in patients with ASD and their parents, ATRA exhibited an upmodulatory potential on CD38 mRNA [75]. Although there have been almost no follow up studies on ATRA and ASD treatment, there is a possibility that substances affecting CD38 expression, such as ATRA, may be potential therapeutic candidates

Vitamin D in Autism – too much or too little?

Reader’s of this blog will be aware that serotonin plays a major role in autism, and also in many other mental health conditions, like depression.

Vitamin D also regularly raises its head in discussions about autism.  You may recall the Somali autism clusters in Sweden and Minneapolis; researchers suggested that the Somali immigrants were not getting enough sun and therefore lacked vitamin D and so produced children with autism.  I did point out that another large Somali autism cluster exists in sun-drenched San Diego.

Even Martha Herbert talks about vitamin D deficiency and autism.

A while back we had a guest blogger, Seth Bittker, present his opposing view, that too much vitamin D added to food in the American diet may be contributing to the rise in autism there.

In same week that Seth has published his paper on this subject, yet another paper has appeared with the opposing view.  So who is right?

The case for (even) more Vitamin D

The first paper is:- 

Vitamin D hormone regulates serotonin synthesis. Part 1:relevance for autism

 

The authors make the following case:-

Serotonin and vitamin D have been proposed to play a role in autism, however, no causal mechanism has been established. Now, researchers show that serotonin, oxytocin, and vasopressin, three brain hormones that affect social behavior related to autism, are all activated by vitamin D hormone. Supplementation with vitamin D and tryptophan would be a practical and affordable solution to help prevent autism and possibly ameliorate some symptoms of the disorder.

After absorbing L-tryptophan from food, our bodies convert it to 5-HTP (5-hyrdoxytryptophan), and then to serotonin.

The supplements L-tryptophan and 5-HTP are widely available and have been used in ADHD and autism but there is no evidence that they are effective.  All that has been shown is that too little tryptophan is bad; there is nothing to show that abnormally large amounts do any good.

If you read the full paper there is an excellent explanation of the role of serotonin in autism.  It is beyond doubt that in many kids with ASD there is high blood serotonin, but low brain serotonin.

To fully treat autism, one thing to be done is to raise brain serotonin levels, without any nasty side effects.  SSRI drugs like Prozac, used to treat depression, do raise brain serotonin but often cause dependence and side effects (like suicidal thought).

It would be great if some vitamin D and tryptophan could do the job.

If you read the older literature, you will see that there is nothing new about the idea to supplement with Tryptophan in autism.  The results to date have been nothing special.

Here is a paper by Paul Whiteley and Paul Shattock:-
 

Effects of Supplementation with Tryptophan and derivatives.  

“It has been shown that a diet depleted of tryptophan is not beneficial for children with ASDs and that some symptoms are exacerbated. Presumably, the existing lack of available serotonin (and other tryptophan derivatives) was exacerbated under these circumstances. Supplementation with tryptophan would probably not be helpful in the majority of cases because the conversions along the important pathways are inhibited and tryptophan is likely to be converted along the IAG route, which would be unhelpful. Anecdotal clinical reports suggest that some children show benefits and others may get worse but no formal studies have been reported.

For this reason, and because tryptophan is a prescription-only drug*, we have looked at other methodologies. The active transmitter, serotonin, does not cross the blood brain barrier and so would be ineffectual in this respect. However, the precursor molecule 5-HTP does cross the blood brain barrier and reach the appropriate target areas. Some parents have reported impressive consequences, particularly with regard to sleep patterns; some physicians have been able to reduce the doses of e.g. risperidone (an anti-psychotic drug) by supplementing 5-HTP but, on the whole, the results have been less useful than would have been predicted.”

Vitamin D and Children with ASD

Children with autism are probably amongst the most “vitamin-supplemented” of any, since parents tend to give copious amounts of multi-vitamins and also vitamin D rich omega 3 fish oil.  It is hard to imagine that any of these children are deficient in vitamin D.

 

The case for too much vitamin D

In his paper, Bittker seeks to correlate the increase in vitamin D fortification in America with the rise in autism; he highlights groups that do not have vitamin D fortified food and where autism is far less prevalent.

Infant Exposure to Excessive Vitamin D: A Risk Factor for Autism

 

Conclusion

So who is right?  Well for sure too little tryptophan or vitamin D is bad for you; but are abnormally high levels good or bad?  In the case of tryptophan, plenty of people have tried supplementation in autism and ADHD and we would probably have heard if it produced a great effect.

Do large amounts of vitamin D help with autism? I very much doubt it, but it would be very easy to do a trial, assuming you found some parents who had not read the Bittker paper.

The good thing is that raising the low level of brain serotonin seems agreed by everyone as a prime target of any autism intervention. For me, vitamin D and tryptophan is not the answer.