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Showing posts with label Verapamil. Show all posts
Showing posts with label Verapamil. Show all posts

Tuesday, 17 September 2024

Is it safe to treat autism in very young children? Plus, the impact of impaired autophagy on cognition and treating SIB


This blog is full of clinical trials that use existing drugs that are repurposed to treat autism. One constant issue is whether the trial drug is free from side effects. Generally speaking side effects tend not to be a problem, but there always can be exceptions.

I was recently contacted by the parents of a two year old with a single gene (monogenic) type of autism and they want to treat their child to improve his outcome.  This is the youngest case I have encountered.

With monogenic autisms you often have clear indications from a very early age that something unusual is present. Once you have a diagnosis you quickly discover what issues the child is going to face. You therefore have a good idea of what will happen if you do nothing. Some other two year olds have delayed speech and other signs of autism, but within a couple of years develop normally – it was a case of delayed maturation.

I noted long ago that American autism doctors tend to want to treat younger patients with supplements rather than drugs.

The reality is that the sooner you start to correct a severe biological dysfunction the better the outcome will be. We even see that some treatments are only effective if given to toddlers. This makes perfect sense although it may be uncomfortable to accept.

I was looking for supporting evidence for very early intervention. I found a glowing report of the treatment of a 2 year old with Fragile X syndrome using Metformin. I am amazed Fragile X still remains untreated in most cases.

On examination at age 2 years, typical physical features of FXS were observed, and baseline laboratory findings were normal (see Table Table1).1). He was started on metformin at 25 mg of the liquid form that is 100 mg/ml at dinner, and his dose was gradually increased to 200 mg twice a day (bid) over 1 year (see Table Table1).1). After initiation of metformin, his sleep disturbance resolved, only occasionally awakening once for roughly 30 min. Two weeks after initiation, he went from stacking 3–4 blocks to stacking a tower of 11 or more blocks; within a few more weeks, he began building more complex structures comprised of different size blocks. He showed marked improvement in self‐help and motor activities, including toilet training, clearing the table and loading the dishwasher, brushing his own teeth, dressing independently, and learning how to make toast. His preschool teachers, who were unaware of metformin treatment, told his mother that “it's like something just clicked or he just woke up. He's a whole different kid.”

Source: Metformin treatment in young children with fragile X syndrome


Some drugs including bumetanide are already safely given to babies.

Nonetheless, it is a brave step to start treatment in a two year old. I did connect the parents to a reader of this blog whose child has the same syndrome but is a few years older.

Today’s post was prompted by the news that the child is already showing improvements from the first therapy, which is a small dose of clemastine. In this syndrome there is a mutation in TCF4 and there is impaired myelination and very likely activated microglia (the brain’s immune cells). The near immediate beneficial effect cannot be on myelination, but it could be resetting microglia to the resting state.

Other genes very recently raised have been TRIT1 and PSMB9; neither of these are classed as autism genes, but evidently can cause it. Mutations in TRIT1 cause a problem in the mitochondria and PSMB9 mutations cause the immune system to misbehave.  It looks like both can lead to an autism diagnosis.

A common issue parents encounter is that often the interest shown by researchers and clinicians stops at the point of diagnosis. What really matters is what to do next. Only very rarely will such “experts” suggest what to do next. 

It looks like there nearly always are therapeutic avenues to pursue after such a diagnosis. It should be noted that even in single gene (monogenic) autisms there are varying levels of response to the same therapy. We saw this a while back with the new FDA approved therapy for Rett syndrome – it works for some, but not for others.

 

Treating self injurious behavior (SIB) in idiopathic autism

I recently received feedback from several parents who have had success in treating SIB based on ideas in this blog.

Verapamil came up again as successful.

Pioglitazone, at a low dose of 7.5mg, was the game changer for one child.

Ibuprofen worked in another case, but this cannot be used long term. Celecoxib should be better tolerated and in theory should be as effective. Time will tell.

More people are trying the add-on therapy of a small dose of taurine.

 

Macroautophagy as a cause of impaired cognition

Impaired autophagy came up recently in two people’s genetic testing results. There is a lot in this blog about autophagy and dementia/mild cognitive impairment.

Today we have a paper that links impaired autophagy with impaired cognition.

Twenty years ago severe autism generally also meant impaired cognition. Nowadays it does not; you can have severe autism with normal cognition.

There are various different types of autophagy but in general it is all about collecting bits of cellular garbage that might clog things up. As we get older this intracellular garbage collection process works less well and then diseases like Alzheimer’s follow decades later.

Impaired autophagy may contribute to impaired cognition at any age. Most research concerns dementia treatment, or other conditions affecting older people like Huntington’s disease.

There is little focus on younger populations, even though we know that children with Down syndrome are prone to get early onset Alzheimer’s. Treating young people with Down syndrome to improve autophagy might bring both short and long term benefits. 

Here is the recent paper on this subject. 

Impaired macroautophagy confers substantial risk for intellectual disability in children with autism spectrum disorders

Autism spectrum disorder (ASD) represents a complex of neurological and developmental disabilities characterized by clinical and genetic heterogeneity. While the causes of ASD are still unknown, many ASD risk factors are found to converge on intracellular quality control mechanisms that are essential for cellular homeostasis, including the autophagy-lysosomal degradation pathway. Studies have reported impaired autophagy in ASD human brain and ASD-like synapse pathology and behaviors in mouse models of brain autophagy deficiency, highlighting an essential role for defective autophagy in ASD pathogenesis. To determine whether altered autophagy in the brain may also occur in peripheral cells that might provide useful biomarkers, we assessed activities of autophagy in lymphoblasts from ASD and control subjects. We find that lymphoblast autophagy is compromised in a subset of ASD participants due to impaired autophagy induction. Similar changes in autophagy are detected in postmortem human brains from ASD individuals and in brain and peripheral blood mononuclear cells from syndromic ASD mouse models. Remarkably, we find a strong correlation between impaired autophagy and intellectual disability in ASD participants. By depleting the key autophagy gene Atg7 from different brain cells, we provide further evidence that autophagy deficiency causes cognitive impairment in mice. Together, our findings suggest autophagy dysfunction as a convergent mechanism that can be detected in peripheral blood cells from a subset of autistic individuals, and that lymphoblast autophagy may serve as a biomarker to stratify ASD patients for the development of targeted interventions.

 

There are different types of autophagy and there are some overlaps. 

·      mTOR dependent (Fasting or Rapamycin)

·      AMPK dependent (Spermidine)

·      P53 dependent (no simple therapies)

·      Calcium signalling dependent (Verapamil)

The OTC way to increase autophagy is to use Spermidine, which is made from wheat germ or rice germ. Studies in humans are rather mixed and I think the dose is likely far too low. Supplements tend to contain about 1mg; I suspect you need much more to have an impact. You can indeed grow your own wheat sprouts which are highly nutritious and a rich source of spermidine. You can eat them raw or even in smoothies. 100 g of sprouts contains 10-15mg of spermidine.

The most researched calcium channel drug to induce autophagy is Verapamil, from my son’s original autism Polypill.

My takeaway continues to be to look for convergent mechanisms, like impaired autophagy, myelination, microglial activation etc that commonly occur in severe autism, of any origin. You then try and treat these likely dysfunctions rather than getting overly focused on individual genes.



 



Monday, 7 August 2023

Differential Diagnosis and Treatment in Autism – Verapamil & Curcumin for Williams Syndrome?


 

The face of Williams syndrome kids. Source: Figure 2.  GeneReviews® - NCBI Bookshelf


Continuing from the last post, today we look again at differential diagnosis and treatment, which I prefer to just call personalized medicine.

This is the subject of a conference for parents in the UK, that I agreed to draw to the attention of readers.

 

Click on the picture above to read about the upcoming event in London.

 

 

Williams syndrome

Williams syndrome: MedlinePlus Genetics (click for info)

Williams syndrome occurs when someone is missing a small piece of chromosome 7, resulting in them lacking 25 to 27 genes. Most people with Williams syndrome have not inherited the condition from a parent.

Williams syndrome can delay a child’s milestones including:

·         Learning (mild to moderate intellectual challenges)

·         Saying their first words and talking

·         Sitting and walking

Socializing is unusual – there is excessive empathy. A child will be outgoing and very friendly, but has difficulty identifying strangers. There may be attention problems, phobias, or anxiety.

Williams is another syndrome with distinct facial features that can help with diagnosis.

·         Large ears

·         Full cheeks

·         Small jaw

·         Wide mouth

·         Small teeth

·         Upturned nose

Williams syndrome is still viewed as untreatable.

In this blog we always start from the basis that all severe autism is potentially treatable.  Often some of the downstream effects of genetic mutations overlap with other types of autism and some of these effects actually are treatable.

There is a great deal in this blog about targeting both calcium channels and potassium channels to treat autism. Verapamil and Ponstan are the two drugs I have written most about.

Curcumin is an OTC therapy for autism that has been widely covered in this blog and people do regularly write to me to tell me that it is beneficial.  Just last week a reader told me that both Ponstan and Curcumin are beneficial in his specific case.

I was intrigued to read the paper from Spain below where the researchers found the combination of Verapamil + Curcumin to improve behaviors in Williams syndrome.  The mechanism was found to be by regulation of MAPK pathway and microglia overexpression.

 

Verapamil + Curcumin to treat the behavioral issues in Williams syndrome

One key takeaway is that in the model of Williams syndrome you need both verapamil (VER) and curcumin (CUR). Either intervention on its own provided no benefit – you need the combination (VERCUR). 


Co-Treatment With Verapamil and Curcumin Attenuates the Behavioral Alterations Observed in Williams–Beuren Syndrome Mice by Regulation of MAPK Pathway and Microglia Overexpression

Williams–Beuren syndrome (WBS) is a rare neurodevelopmental disorder characterized by a distinctive cognitive phenotype for which there are currently no effective treatments. We investigated the progression of behavioral deficits present in WBS complete deletion (CD) mice, after chronic treatment with curcumin, verapamil, and a combination of both. These compounds have been proven to have beneficial effects over different cognitive aspects of various murine models and, thus, may have neuroprotective effects in WBS. Treatment was administered orally dissolved in drinking water. A set of behavioral tests demonstrated the efficiency of combinatorial treatment. Some histological and molecular analyses were performed to analyze the effects of treatment and its underlying mechanism. CD mice showed an increased density of activated microglia in the motor cortex and CA1 hippocampal region, which was prevented by co-treatment. Behavioral improvement correlated with the molecular recovery of several affected pathways regarding MAPK signaling, in tight relation to the control of synaptic transmission, and inflammation. Therefore, the results show that co-treatment prevented behavioral deficits by recovering altered gene expression in the cortex of CD mice and reducing activated microglia. These findings unravel the mechanisms underlying the beneficial effects of this novel treatment on behavioral deficits observed in CD mice and suggest that the combination of curcumin and verapamil could be a potential candidate to treat the cognitive impairments in WBS patients.

Accumulated evidence has described that curcumin, the major constituent of turmeric (Curcuma longa), exerts a variety of pharmacological effects due to its antioxidant, anti-inflammatory, and neuroprotective properties. Recent studies have reported positive effects of curcumin over different cognitive aspects such as anxiety-like behaviors, memory deficits, and motor impairments of different murine models Many studies have described that its effects on the behavioral phenotype of mice models are mediated by upregulation of BDNF (brain-derived neurotrophic factor) expression BDNF has been described as a crucial molecule for neural development and plasticity processes and its mechanism of action is highly dependent on a proper maintenance of intracellular ionic homeostasis Moreover, it has also been described to prevent neuroinflammation by modulating pathways related to NRF2 and MAPK signaling.

Verapamil is a widely used medication, and its mechanism of action involves mainly the blocking of voltage-dependent calcium channels, but it has also been proven to directly bind and block voltage-gated potassium channels  and to inhibit drug efflux pump proteins like P-glycoprotein. Although it has been mainly studied for cardiovascular applications, it has also been associated with positive effects on anxiety and memory processing in murine models.

Given the properties of both compounds, we decided to explore the effects of each compound and a combinatorial treatment on the behavioral phenotype of CD mice. The results show that only the combined treatment with curcumin and verapamil improved the deficits. This improvement can be correlated with the normalization of the MAPK and inflammasome signaling pathways and with the concomitant reduction of activated microglia. 

·   The Increased Microglia Activation in Motor Cortex and Hippocampus Presented by CD Mice Is Prevented by VERCUR Co-Treatment

·    Combinatorial Treatment Prevents Hypersociability of CD Mice

·    Only VERCUR Co-Treatment Improves Motor Coordination in CD Mice

·    VERCUR Co-Treatment Prevents Gene Expression Changes in Cortex of CD Animals

·    Neuroanatomical Features of CD Mice Do Not Change After VERCUR Co-Treatment

In conclusion, we suggest that the hemizygous loss of WBSCR in the cerebral cortex of CD mice has a direct effect on the neuroinflammatory state of the brain, as well as on the expression of some genes related to synaptic signaling or extracellular matrix structure, which are crucial for a proper neural function. This may at least be partly responsible for the behavioral phenotype observed in CD animals. A treatment combining verapamil and curcumin is able to address different molecular targets and rescue some of those pathways, being a promising therapeutic approach for the cognitive phenotype of WBS patients.

  

Conclusion 

Today’s study was in a mouse model of William’s syndrome; clearly it would be more informative if the researchers had tried it on humans.  It does though raise the question as to what other treatments from idiopathic autism might be effective in this supposedly untreatable genetic condition.

The other perspective of course is to wonder what other types of autism might benefit from Verapamil plus curcumin (VERCUR). It was interesting to note that in the model neither Verapamil nor curcumin was effective by itself, they needed the combined therapy (VERCUR).

If you read the experiences that have been shared over the years in this blog you can see that some parents spend a lot of money on genetic testing, hoping to improve their child’s outcome.  It is only very rarely that you see any great success resulting.

The alternative approach is understand the commonly shared biological features of autism and try and treat those, to see whether the individual shows a benefit.  Where there is a positive response, it is a “keeper,” if there is no response, or a negative response, the therapy is dropped.  Essentially it is a process of trial and error.  Not as fancy as genetic testing, but it works.

Clearly if your child has Williams syndrome you would be well advised to look up the function of each of the 26 missing genes, to see if there are any obvious steps to take. One good tool to use is www.genecards.org.  


Old posts that refer to cucumin:

Epiphany: Curcumin (epiphanyasd.com)

 

Old posts that refer to verapamil

Epiphany: Verapamil (epiphanyasd.com)






Sunday, 23 October 2022

Calcium channelopathies and intellectual disability

 

Changsha, another big city in China you probably have not heard of

 

Today’s post follows up on the use of calcium channel blockers to treat autism.  This is a subject that I first looked at in this blog several years ago.  One of our readers even wrote a book entirely about this subject.

There has been plenty of research going back a decade or more, but no effort to translate it into common therapy.

By coincidence, one reader recently sent me a list of about 20 suspect genes from her daughter’s tests. 7 are related to just a pair of L-type calcium channels, the suggested action was to take magnesium sulfate. I referred her back to my old posts, particularly since her main concern is self-injury. I have written a great deal about Cav1.2 and self-injury, since it is treatable using Verapamil. 



I think a better interpretation of the genetic testing results would have been to say possible channelopathies in Cav1.2 and Cav1.3.  Given that mutations usually lead to over expression of ion channels, a likely effective therapy would be to block these channels.

Magnesium does act as a calcium channel blocker, among its very many other effects.

Is magnesium sulfate the best choice of Cav1.2 and Cav1.3 blocker?  I doubt it, but at least it is OTC. 

 

Treating Intellectual Disability (ID) rather than Autism

I do often think that we should be talking more about treating ID rather than autism.

Who would object to treating ID? Hopefully nobody.

Today’s paper is about treating intellectual disability (ID) and global developmental delay (GDD).

Almost all people with level 3 autism could also be described as ID + GDD.

Level 3 autism = ID + GDD

We also have IDD which is Intellectual and Developmental Disability.

Too many names for the same thing, if you ask me.

The paper below from Changsha, China starts with the hypothesis that:-

Calcium Channels play a major role in the development of ID/GDD and that both gain- and loss-of-function variants of calcium channel genes can induce ID/GDD.

The paper is published in the  Orphanet Journal of Rare Diseases.

2.3% of the general population have an IQ less than 70 and so have intellectual disability (ID).  ID is not really rare. More than 1 million people in the United States have intellectual disability (ID). 

There are many different processes involved in intellectual disability (ID).  On the one hand that makes it complicated, but on the other hand that means there are many options beyond just L-type calcium channels blockers.

The paper below is really only looking and at Cav1.2 and Cav1.3.  As I pointed out in my previous post, there is much more to it than just this pair.

On the bright side, at least some people in China are looking at this.

  

Calcium channelopathies and intellectual disability: a systematic review


Background

Calcium ions are involved in several human cellular processes including corticogenesis, transcription, and synaptogenesis. Nevertheless, the relationship between calcium channelopathies (CCs) and intellectual disability (ID)/global developmental delay (GDD) has been poorly investigated. We hypothesised that CCs play a major role in the development of ID/GDD and that both gain- and loss-of-function variants of calcium channel genes can induce ID/GDD. As a result, we performed a systematic review to investigate the contribution of CCs, potential mechanisms underlying their involvement in ID/GDD, advancements in cell and animal models, treatments, brain anomalies in patients with CCs, and the existing gaps in the knowledge. We performed a systematic search in PubMed, Embase, ClinVar, OMIM, ClinGen, Gene Reviews, DECIPHER and LOVD databases to search for articles/records published before March 2021. The following search strategies were employed: ID and calcium channel, mental retardation and calcium channel, GDD and calcium channel, developmental delay and calcium channel.

 

Main body

A total of 59 reports describing 159 cases were found in PubMed, Embase, ClinVar, and LOVD databases. Variations in ten calcium channel genes including CACNA1A, CACNA1CCACNA1I, CACNA1H, CACNA1DCACNA2D1CACNA2D2CACNA1ECACNA1F, and CACNA1G were found to be associated with ID/GDD. Most variants exhibited gain-of-function effect. Severe to profound ID/GDD was observed more for the cases with gain-of-function variants as compared to those with loss-of-function. CACNA1ECACNA1GCACNA1FCACNA2D2 and CACNA1A associated with more severe phenotype. Furthermore, 157 copy number variations (CNVs) spanning calcium genes were identified in DECIPHER database. The leading genes included CACNA1CCACNA1A, and CACNA1E. Overall, the underlying mechanisms included gain- and/ or loss-of-function, alteration in kinetics (activation, inactivation) and dominant-negative effects of truncated forms of alpha1 subunits. Forty of the identified cases featured cerebellar atrophy. We identified only a few cell and animal studies that focused on the mechanisms of ID/GDD in relation to CCs. There is a scarcity of studies on treatment options for ID/GDD both in vivo and in vitro.

 

Conclusion

Our results suggest that CCs play a major role in ID/GDD. While both gain- and loss-of-function variants are associated with ID/GDD, the mechanisms underlying their involvement need further scrutiny.

 

Discussion

Overall, this condition seems to be progressive, however, most primary authors provided less information on the course of the disease. Many of the reported cases with electrophysiological studies had gain-of- function variants. Severe to profound ID/GDD was more predominant for the cases with gain-of-function variants as compared to those with loss-of-function. CACNA1ECACNA1GCACNA1FCACNA2D2 and CACNA1A associated with more severe phenotype. The possible reasons as why these genes associated with more severe phenotype include (1) the neuronal location of the genes; all of them are located in the pre-synaptic membrane, (2) brain distribution; most of them are distributed in the brain cortex and/or hippocampus and/or cerebellum, (3) function of the genes; they all regulate the release of neurotransmitter, and (4) the effect of the variants; most of the reported variants in these genes had gain-of-function property. This review has also revealed some hotspots for future research.

  

Conclusion

Gain of function of Cav1.2 and Cav1.3 continues to be well documented in the literature.  That means too much calcium (Ca2+ ) entering neurons, from outside.

Note that inside cells/neurons you have a store of Ca2+ in something called the Endoplasmic Reticulum (ER). There is supposed to be a high level of Ca2+ inside the ER.  When things go wrong, there can be ER stress and Ca2+ may get pushed out, or too much Ca2+ may be let in. ER stress plays a role in many diseases including autism. In autism the channel implicated is called IP3R. ER stress ultimately leads to cell death. This is the mechanism behind how people with diabetes stop producing insulin. ER stress in the beta cells in their pancreas caused the beta cells to die. No beta cells means no insulin. In such people very prompt treatment by blocking Cav1.2 stops the beta cells dying.

The people seeing a benefit from blocking Cav1.2 and/or Cav1.3 in someone with autism, ID, IDD, GDD, ADHD, epilepsy, SIB, or chronic headaches etc, have science on their side.  It is not just Chinese science; it is science from everywhere.

Note that ion channel dysfunctions can be genetic (they show up on genetic tests) or they can be acquired (they do not show up on testing).

The open issue is what is the most effective therapy.  This is going to vary from person to person, but it is unlikely to be magnesium sulfate.

Magnesium is an important mineral to get from a healthy diet, but it has many effects including blocking NMDA receptors.  This effect might be good or it might be bad. High doses of magnesium supplements will cause GI problems. Most people lack magnesium so a little extra would seem fine, but using enough to block calcium channels may not be wise.

Blocking Cav1.3 will Amlodipine should be the subject of a clinical trial.

Blocking Cav1.2 with Verapamil should be the subject of a clinical trial.

Maybe in China?






Thursday, 6 October 2022

Different L-type Calcium Channel Blockers Repurposed for Different Types of Autism

 

 A Purkinje Neuron, home of P-type calcium channels

Today’s post was prompted by a reader who saw a very positive response from the L-type calcium channel blocker, Amlodipine.

So we return to the subject of calcium channels.

The good news about calcium channel defects is that many are easy to treat.

In most single gene autisms (Rett, Fragile-X, Pitt Hopkins etc) the underlying problem is that a faulty gene does not do its job of producing the expected protein.  This is a problem of too little.

In many ion channel dysfunctions the problem is not too little, it is too much expression. For example, in Timothy Syndrome the mutation in the gene produces too much of the protein, in this case the L-type calcium channel Cav1.2.

Ion channel dysfunctions can be the result of a faulty gene, or just that the on/off switch for that gene is faulty.  Fortunately, the problem is usually that it is stuck “on”.

In people who develop Type-1 diabetes we have seen how the disease process can be halted by blocking Cav1.2 in the pancreas.  This halts the decline in the beta cells that produce insulin.

Once all the beta cells are dead, the person cannot produce insulin and has type-1 diabetes. Treating the person after this point with a Cav1.2 blocker will provide no benefit; the damage has already been done

Something similar happens in Parkinson’s disease, but this time you need to block Cav1.3.  In the early stages of the disease Cav1.3 is over-expressed in a key part of the brain, which triggers a slow process of degeneration. Treating a person with all the visible symptoms of Parkinson’s with a Cav1.3 blocker will provide no benefit; the damage has already been done.

 

Calcium channel blockers are not very specific

The current drugs used to block calcium channels were mainly developed to treat heart conditions.

When treating neurological disorders like autism we are primarily focused on the brain, what goes on elsewhere can also be very relevant, but in an indirect way.

In the brain the important calcium channels are: -

L type

N type

P type

R type

T type

Plus, Inositol trisphosphate receptor (IP3R) and Ryanodine receptors. IP3R has been covered in previous posts.


Verapamil (a Phenylalkylamine class drug)

Verapamil blocks L type channels and T type channels, plus some potassium ion channels.

When it comes to specific L type channels there are 4, Cav1.1, Cav1.2, Cav1.3, and Cav1.4.

In the brain we have just Cav1.2 and Cav1.3. Verapamil mainly affects Cav1.2.

 

Amlodipine (a Dihydropyridine class drug)

Amlodipine blocks L type channels and N type channels.

Amlodipine mainly affects Cav1.3.

 

Nicardipine (a Dihydropyridine class drug)

Nicardipine blocks L type channels and N type channels.

As a Dihydropyridine, it should mainly affect Cav1.3.

In addition, it blocks the sodium ion channel Nav1.8.

The effect on Nav1.8 is why it has been proposed as a therapy for Pitt Hopkins. In this syndrome Nav1.8 is over expressed as a downstream consequence of a mutation in the TCF4 gene.

 

Effect on P channels

To some extent Verapamil, Amlodipine and Nicardipine all block P channels.

P channels are called P after the Purkinje neurons, where they are located. These Purkinje cells likely define some aspects of autism, because of their absence. Purkinje neurons are among the largest in the brain, with elaborate dendritic arbor.  I imagine this makes them vulnerable.




In the people with severe autism most of the Purkinje cells appear to have died.

Blocking P channels might have protected Purkinje cells from death.

 

The effect of too much L-type calcium channel signaling on behavior 

You can both turn on self-injury via activating L type calcium channels and extinguish it by blocking the same channels.  It is proven in mice and seems to apply to at least some humans.

Calcium channel activation and self-biting in mice

The L type calcium channel agonist (±)Bay K 8644 has been reported to cause characteristic motor abnormalities in adult mice. The current study shows that administration of this drug can also cause the unusual phenomenon of self-injurious biting, particularly when given to young mice.

The self-biting provoked by (±)Bay K 8644 can be inhibited by pretreating the mice with dihydropyridine L type calcium channel antagonists such as nifedipine, nimodipine, or nitrendipine. However, self-biting is not inhibited by nondihydropyridine antagonists including diltiazem, flunarizine, or verapamil.

(±)Bay K 8644 functions as an L type calcium channel activator that increases calcium fluxes in response to depolarizing stimuli (). In rodents, this drug has been reported to produce characteristic motor abnormalities including impaired ambulation, twisting and stretching movements, transient limb extension, back arching, spasticity, ataxia, or catatonia (). Some studies have anecdotally noted the occurrence of SIB with this drug (), though this phenomenon has received little attention. The current study shows that (±)Bay K 8644 will reliably provoke SB and SIB under certain conditions in mice, providing a tool to study the neurobiology of this unusual behavior.

 

When I first encountered the above study, I did wonder why Verapamil did not extinguish the self-injury.

It turns out that Bay K 8644 is a modified version of the common drug nifedipine, which is a Cav1.3 blocker.  Verapamil is mainly a Cav1.2 blocker.  Bay K 8644 is like the opposite of nifedipine.

In the trial they have activated Cav1.3 causing excess calcium inside neurons. The only way to block this process is to block Cav1.3. Blocking Cav1.2 with Verapamil could not solve the problem. 

Note that activation of Cav1.3 can cause motor abnormities in mice and this might be seen as ataxia in a human. One particular reader of this blog will see the relevance of this. 

I did write extensively in earlier posts about the large amount of research that links L type calcium channels to neuropsychiatric disorders.

I did mainly focus on Cav1.2 using Verapamil, but the evidence for the role of Cav1.3 is clear as day. 

L-type calcium channels as drug targets in CNS disorders

 L-type calcium channels are present in most electrically excitable cells and are needed for proper brain, muscle, endocrine and sensory function. There is accumulating evidence for their involvement in brain diseases such as Parkinson disease, febrile seizures and neuropsychiatric disorders. Pharmacological inhibition of brain L-type channel isoforms, Cav1.2 and Cav1.3, may therefore be of therapeutic value.

 

From Gene to Behavior: L-Type Calcium Channel Mechanisms Underlying Neuropsychiatric Symptoms.

The L-type calcium channels (LTCCs) Cav1.2 and Cav1.3, encoded by the CACNA1C and CACNA1D genes, respectively, are important regulators of calcium influx into cells and are critical for normal brain development and plasticity. In humans, CACNA1C has emerged as one of the most widely reproduced and prominent candidate risk genes for a range of neuropsychiatric disorders, including bipolar disorder (BD), schizophrenia (SCZ), major depressive disorder, autism spectrum disorder, and attention deficit hyperactivity disorder.

Here, we provide a review of clinical studies that have evaluated LTCC blockers for BD, SCZ, and drug dependence-associated symptoms, as well as rodent studies that have identified Cav1.2- and Cav1.3-specific molecular and cellular cascades that underlie mood (anxiety, depression), social behavior, cognition, and addiction.

 

Was I surprised that Amlodipine, that targets Cav1.3 rather than Cav1.2, was very beneficial in someone with severe autism?  Not at all.

I was interested that the effect was more pro-cognitive than anti-anxiety.  Is that the effect on Cav1.3 or is it via that N channel Cav2.2?

N-type calcium channels are important in neurotransmitter release because they are localized at the synaptic terminals. Piracetam, the original cognitive enhancing drug, is also a N type channel blocker.

  

Statins and L type calcium channels blockers – it matters which one you choose

We previously saw how the statin class of drugs can be beneficial in autism, but it depends which one you chose. For example, in SLOS (Smith-Lemli-Opitz syndrome), where both copies of the gene DHCR7 are mutated, you need to push the gene to work. To increase expression of this gene you need Simvastatin. This is hard for people to understand because SLOS features very low cholesterol and statins are thought of as cholesterol lowering drugs. The body needs the enzyme DHCR7 to make cholesterol and Simvastatin increases DHCR7 expression.

In the case of L type channel blockers, the selection is very important.  The effect will not be the same.

If you have a mutation in Cav1.2, you would expect Verapamil to be a good choice.  If the mutation is in Cav1.3, you would expect Amlodipine to be better.

If you have over expression of T channels (Cav3.1, Cav3.2 or Cav3.3) then you would expect a benefit from Verapamil and none from Amlodipine.

If you have over expression of the N channel (Cav2.2) then you would want Amlodipine

If you have over expression of the sodium channel Nav1.8 then you would want Nicardipine

  

Conclusion

It is likely that many people with autism, bipolar, ADHD or schizophrenia might benefit from treating their ion channel dysfunctions.  The required drugs are cheap generics that have been in your local pharmacy for a few decades.

Back in 2019 I wrote the post below:

Cheap common drugs may help mental illness

I highlighted a new study, using historic data from Sweden, that looked at the secondary effects of statins, calcium channel blockers and metformin on psychiatric hospitalization.

 

Association of Hydroxylmethyl Glutaryl Coenzyme A Reductase Inhibitors, L-Type Calcium Channel Antagonists, and Biguanides With Rates of Psychiatric Hospitalization and Self-Harm in Individuals With Serious Mental Illness

 

Question  Are drugs in common use for physical health problems (hydroxylmethyl glutaryl coenzyme A reductase inhibitors, L-type calcium channel antagonists, and biguanides) associated with reduced rates of psychiatric hospitalization and self-harm in individuals with serious mental illness?

Findings  In this series of within-individual cohort studies of 142 691 patients with bipolar disorder, schizophrenia, or nonaffective psychosis, exposure to any of the study drugs was associated with reduced rates of psychiatric hospitalization compared with unexposed periods. Self-harm was reduced in patients with bipolar disorder and schizophrenia during exposure to all study drugs and in patients with nonaffective psychosis taking L-type calcium channel antagonists. 

We found that periods of HMG-CoA RI (statin) exposure were associated with reduced psychiatric hospitalization in all subgroups of SMI (Serious Mental Illness) and with reduced self-harm in BPD and schizophrenia.

Exposure to LTCC (L type calcium channel) antagonists was associated with reduced rates of psychiatric hospitalization and self-harm.

Periods of metformin (a type 2 diabetes drug) exposure were associated with reduced psychiatric and nonpsychiatric hospitalization across all SMI subgroups.

 

Use of L type calcium channel blockers reduces self-harm.

How much more evidence is needed?

I took an educated guess several years ago that Verapamil would tame summertime raging in my son.  It was the only calcium channel blocker I tried and it worked. This year we had the emergence of extreme sound sensitivity. My educated guess was that blocking potassium channels with Ponstan (Mefenamic acid) would resolve the problem, and it did.  

Treating ion channel dysfunctions (channelopathies) in autism clearly is not rocket science; it is just waiting to be attempted.