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Showing posts with label Pitt Hopkins. Show all posts
Showing posts with label Pitt Hopkins. Show all posts

Wednesday 10 May 2023

Low dose Clonazepam for MIA Autism, Ponstan and TRPM3 in Intellectual Disability, Clemastine to restore myelination in Pitt Hopkins, Improving Oxytocin therapy with Maca, Lamotrigine for some autism

 

Monty in Ginza, Tokyo

Today’s post comes from Tokyo and looks at 5 therapies already discussed in previous posts and follows up on recent coverage in the research. They all came up in recent conversations I have been having.

·      Low dose Clonazepam  – Maternal Immune Activation model of autism

·      Ponstan – TRPM3 causing intellectual disability  (ID/MR)

·      Clemastine – improving myelination in Pitt Hopkins syndrome model

·      Oxytocin – Maca supplement to boost effect

·      Lamotrigine (an anti-epilepsy drug) to moderate autism

The good news is that many of same therapies keep coming up.


Ponstan and TRPM3 caused ID/MR

There is a lot in this blog about improving cognition, which is how I called treating ID/MR.  There are very many causes of ID and some of them are treatable.

ID/MR was always a part of classic autism and in the new jargon is part of what they want to call profound autism.

I was recently sent a paper showing how the cheap pain reliever Ponstan blocks the TRMP3 channel and that this channel when mutated can lead to intellectual disability and epilepsy.

Mefenamic acid selectively inhibits TRPM3-mediated calcium entry.

My own research has established that mefenamic acid seems to improve speech and cognition, as well as sound sensitivity.  The latter effect I am putting down to its effect on potassium channels. 

De novo substitutions of TRPM3 cause intellectual disability and epilepsy

The developmental and epileptic encephalopathies (DEE) are a heterogeneous group of chronic encephalopathies frequently associated with rare de novo nonsynonymous coding variants in neuronally expressed genes. Here, we describe eight probands with a DEE phenotype comprising intellectual disability, epilepsy, and hypotonia. Exome trio analysis showed de novo variants in TRPM3, encoding a brain-expressed transient receptor potential channel, in each. Seven probands were identically heterozygous for a recurrent substitution, p.(Val837Met), in TRPM3’s S4–S5 linker region, a conserved domain proposed to undergo conformational change during gated channel opening. The eighth individual was heterozygous for a proline substitution, p.(Pro937Gln), at the boundary between TRPM3’s flexible pore-forming loop and an adjacent alpha-helix. General-population truncating variants and microdeletions occur throughout TRPM3, suggesting a pathomechanism other than simple haploinsufficiency. We conclude that de novo variants in TRPM3 are a cause of intellectual disability and epilepsy.

 

Fenamates as TRP channel blockers: mefenamic acid selectively blocks TRPM3

This study reveals that mefenamic acid selectively inhibits TRPM3-mediated calcium entry. This selectivity was further confirmed using insulin-secreting cells. KATP channel-dependent increases in cytosolic Ca2+ and insulin secretion were not blocked by mefenamic acid, but the selective stimulation of TRPM3-dependent Ca2+ entry and insulin secretion induced by pregnenolone sulphate were inhibited. However, the physiological regulator of TRPM3 in insulin-secreting cells remains to be elucidated, as well as the conditions under which the inhibition of TRPM3 can impair pancreatic β-cell function. Our results strongly suggest mefenamic acid is the most selective fenamate to interfere with TRPM3 function. 

Here, we examined the inhibitory effect of several available fenamates (DCDPC, flufenamic acid, mefenamic acid, meclofenamic acid, niflumic acid, S645648, tolfenamic acid) on the TRPM3 and TRPV4 channels using fluorescence-based FLIPR Ca2+ measurements. To further substantiate the selectivity, we tested the potencies of these fenamates on two other TRP channels from different subfamilies, TRPC6 and TRPM2. In addition, single-cell Ca2+ imaging, whole-cell voltage clamp and insulin secretion experiments revealed mefenamic acid as a selective blocker of TRPM3.

  

Oxytocin

 Oxytocin does increase how emotional you feel; the difficulty is how to administer it in a way that provides a long lasting effect.  The half-life of oxytocin is a just minutes. The traditional method uses a nose spray.

I favour the use of a gut bacteria that stimulates the release of oxytocin in the brain.  The effect should be much longer lasting. Even then the effect is more cute than dramatic.

The supplement Maca does not itself produce oxytocin, but “it restores social recognition impairments by augmenting the oxytocinergic neuronal pathways”.

So Maca looks like an interesting potential add-on therapy to boost the effect of oxytocin.

One reader wrote to me with a positive report on using Maca by itself, without any oxytocin.

 

Oral Supplementation with Maca Improves Social Recognition Deficits in the Valproic Acid Animal Model of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a congenital, lifelong neurodevelopmental disorder whose main symptom is impaired social communication and interaction. However, no drug can treat social deficits in patients with ASD, and treatments to alleviate social behavioral deficits are sorely needed. Here, we examined the effect of oral supplementation of maca (Lepidium meyenii) on social deficits of in utero-exposed valproic acid (VPA) mice, widely used as an ASD model. Although maca is widely consumed as a fertility enhancer and aphrodisiac, it possesses multiple beneficial activities. Additionally, it benefits learning and memory in experimental animal models. Therefore, the effect of maca supplementation on the social behavioral deficit of VPA mice was assessed using a social interaction test, a three-stage open field test, and a five-trial social memory test. The oral supplementation of maca attenuated social interaction behavior deficit and social memory impairment. The number of c-Fos-positive cells and the percentage of c-Fos-positive oxytocin neurons increased in supraoptic and paraventricular neurons of maca-treated VPA mice. These results reveal for the first time that maca is beneficial to social memory and that it restores social recognition impairments by augmenting the oxytocinergic neuronal pathways, which play an essential role in diverse social behaviors.

Maca (Lepidium meyenii) belongs to the cruciferous family and grows at high altitudes in Peru. In 2002, it was transplanted from Peru to the Yunnan Province of China. It is rich in dietary fiber; has many essential amino acids and nutrients including vitamin C, copper, and iron; and its root contains bioactive compounds. It is globally consumed and is popularly used as a fertility enhancer and aphrodisiac. On the other hand, with its potential to possess multi-nutritious components, it is reported to have diverse functions, including immunomodulation, antioxidant, antidepressant, antirheumatic, UV radiation protection, hepatoprotective, anti-fatigue, and neuroprotective effects. Interestingly, although the mechanism of the neuronal effect of maca is unclear, the uptake of maca extract improves learning and memory in memory-impaired model mice induced by either ethanol, ovariectomy, or scopolamine. However, the effects of maca on social memory impairment in neurodevelopmental disorders, including ASD, have not yet been tested.

In this study, the effects of maca on ASD animal models, in utero VPA-exposed mice, were investigated. The effect on social recognition by maca uptake with gavage was assessed using the social interaction test, a three-stage open field test, and the five-trail social recognition test. We also explored whether maca intake affects oxytocinergic signaling pathways, which play an important role in various social behaviors.

In this study, we showed that maca uptake rescues the deficits of social behavior and social recognition memory in VPA mice, a mouse model of autism. The c-Fos immunoreactivity of oxytocinergic neurons in SON and PVN increased significantly after maca treatment in VPA mice. Following previous studies indicating that OT administration ameliorates the impairment of social behavior in VPA mice, maca may also have improving effects on the deficit of social behavior and social recognition memory of VPA mice, probably by activating the OT neuronal pathway. Previous studies showed that maca could improve cognitive function in the mice model of impaired cognitive memory induced by either ovariectomy, ethanol, or scopolamine. Further studies are necessary to elucidate the potential link between maca and OT and to determine which components are involved in improving social recognition memory.

We have shown that maca improves the impairment of social memory and social behavioral deficits through oxytocinergic system modulation in this study. Although maca may not have an immediate effect on social behavioral deficits and takes days or weeks to demonstrate the effects, behavioral improvements, were visible regardless of the time of oral intake. The time between the very last oral intake of maca and the start of the social behavioral experiments in this study was more than 16 h. The duration of the maca’s effect on social behavioral deficits after the supplementation period is being investigated in our follow-up experiments. The possibility of the persistent effect of maca is very appealing, given that OT does not have a sustained effect due to its rapid metabolism, despite its immediate effects. Therefore, taking maca as a supplement while also receiving repeated OT treatment may have a synergistic, sustainable effect on improving social impairment in patients with ASD. Maca is already being used as a dietary supplement worldwide and has a high potential for practical applications.

 

This study showed for the first time that maca supplementation improves the impairment of social recognition memory in ASD model mice. We added the mechanism that social memory improvement may occur through the upregulation of oxytocinergic pathways. Maca highlights the possibility of treating social deficits sustainably in individuals with ASDs.

 

Low dose clonazepam

Professor Catterall was the brains behind low dose clonazepam for mice, I just translated it across to humans. It is one way to modify the E/I (excitatory/inhibitory) imbalance in autism.

I found that it gave a boost to cognition. Not as big as bumetanide, but worth having nonetheless.

I do not believe you have to be a bumetanide responder to respond well to low dose clonazepam.

Several people have written to me recently to say it works for their child.

Our reader Tanya is interested in the Maternal Immune Activation (MIA) trigger to autism. She highlighted a recent study showing how and why clonazepam can reverse autism in the MIA mouse model of autism. 

Clonazepam attenuates neurobehavioral abnormalities in offspring exposed to maternal immune activation by enhancing GABAergic neurotransmission

Ample evidence indicates that maternal immune activation (MIA) during gestation is linked to an increased risk for neurodevelopmental and psychiatric disorders, such as autism spectrum disorder (ASD), anxiety and depression, in offspring. However, the underlying mechanism for such a link remains largely elusive. Here, we performed RNA sequencing (RNA-seq) to examine the transcriptional profiles changes in mice in response to MIA and identified that the expression of Scn1a gene, encoding the pore-forming α-subunit of the brain voltage-gated sodium channel type-1 (NaV1.1) primarily in fast-spiking inhibitory interneurons, was significantly decreased in the medial prefrontal cortex (mPFC) of juvenile offspring after MIA. Moreover, diminished excitatory drive onto interneurons causes reduction of spontaneous gamma-aminobutyric acid (GABA)ergic neurotransmission in the mPFC of MIA offspring, leading to hyperactivity in this brain region. Remarkably, treatment with low-dose benzodiazepines clonazepam, an agonist of GABAA receptors, completely prevented the behavioral abnormalities, including stereotypies, social deficits, anxiety- and depression-like behavior, via increasing inhibitory neurotransmission as well as decreasing neural activity in the mPFC of MIA offspring. Our results demonstrate that decreased expression of NaV1.1 in the mPFC leads to abnormalities in maternal inflammation-related behaviors and provides a potential therapeutic strategy for the abnormal behavioral phenotypes observed in the offspring exposed to MIA.

 

Pitt Hopkins – Clemastine and Sobetirome

Poor myelination is a feature of much autism and is a known problem in Pitt Hopkins syndrome.

I did cover a paper a while back where the Pitt Hopkins researchers showed that genes involved in myelination are down-regulated not only in Pitt Hopkins, but in several other popular models of autism.

From the multiple sclerosis (MS) research we have assembled a long list of therapies to improve different processes involved in myelination. Today we can add to that list sobetirome (and the related Sob-AM2). Sobetirome shares some of its effects with thyroid hormone (TH), it is a thyroid hormone receptor isoform beta-1 (THRβ-1) liver-selective analog.

Some people do use thyroid hormones to treat autism, and indeed US psychiatrists have long used T3 to treat depression.

The problem with giving T3 or T4 hormones is that it has body-wide effects and if you give too much the thyroid gland will just produce less.

One proposed mechanism I wrote about long ago is central hypothyroidism, that is a lack of the active T3 hormone just within the brain. One possible cause proposed was that oxidative stress reduces the enzyme D2 that is used to convert circulating prohormone T4 to T3. The result is that your blood test says your thyoid function is great, but in your brain you lack T3.

It looks like using sobetirome you can spice up myelination in the brain, without causing any negative effects to your thyroid gland.

Rather surprisingly, sobetirome is already sold as a supplement, but it is not cheap like Clemastine, the other drug used in the successful study below.

 

Promyelinating drugs promote functional recovery in an autism spectrum disorder mouse model of Pitt–Hopkins syndrome

Pitt–Hopkins syndrome is an autism spectrum disorder caused by autosomal dominant mutations in the human transcription factor 4 gene (TCF4). One pathobiological process caused by murine Tcf4 mutation is a cell autonomous reduction in oligodendrocytes and myelination. In this study, we show that the promyelinating compounds, clemastine, sobetirome and Sob-AM2 are effective at restoring myelination defects in a Pitt–Hopkins syndrome mouse model. In vitro, clemastine treatment reduced excess oligodendrocyte precursor cells and normalized oligodendrocyte density. In vivo, 2-week intraperitoneal administration of clemastine also normalized oligodendrocyte precursor cell and oligodendrocyte density in the cortex of Tcf4 mutant mice and appeared to increase the number of axons undergoing myelination, as EM imaging of the corpus callosum showed a significant increase in the proportion of uncompacted myelin and an overall reduction in the g-ratio. Importantly, this treatment paradigm resulted in functional rescue by improving electrophysiology and behaviour. To confirm behavioural rescue was achieved via enhancing myelination, we show that treatment with the thyroid hormone receptor agonist sobetirome or its brain penetrating prodrug Sob-AM2, was also effective at normalizing oligodendrocyte precursor cell and oligodendrocyte densities and behaviour in the Pitt–Hopkins syndrome mouse model. Together, these results provide preclinical evidence that promyelinating therapies may be beneficial in Pitt–Hopkins syndrome and potentially other neurodevelopmental disorders characterized by dysmyelination.

 

Sobetirome  (also called GC-1)

Sobetirome is a thyroid hormone receptor isoform beta-1 (THRβ-1) liver-selective analog.

In humans, sobetirome lowers plasma LDL cholesterol and reduced plasma triglycerides, while its liver-selective activity helped avoid the side effects seen with many other thyromimetic agents.

 

Myelin repair stimulated by CNS-selective thyroid hormone action

Oligodendrocyte processes wrap axons to form neuroprotective myelin sheaths, and damage to myelin in disorders, such as multiple sclerosis (MS), leads to neurodegeneration and disability. There are currently no approved treatments for MS that stimulate myelin repair. During development, thyroid hormone (TH) promotes myelination through enhancing oligodendrocyte differentiation; however, TH itself is unsuitable as a remyelination therapy due to adverse systemic effects. This problem is overcome with selective TH agonists, sobetirome and a CNS-selective prodrug of sobetirome called Sob-AM2. We show here that TH and sobetirome stimulated remyelination in standard gliotoxin models of demyelination. We then utilized a genetic mouse model of demyelination and remyelination, in which we employed motor function tests, histology, and MRI to demonstrate that chronic treatment with sobetirome or Sob-AM2 leads to significant improvement in both clinical signs and remyelination. In contrast, chronic treatment with TH in this model inhibited the endogenous myelin repair and exacerbated disease. These results support the clinical investigation of selective CNS-penetrating TH agonists, but not TH, for myelin repair.

 

Compound protects myelin, nerve fibers

 

Research could be important in treating, preventing progression of multiple sclerosis, other neurodegenerative diseases

A compound appears to protect nerve fibers and the fatty sheath, called myelin, that covers nerve cells in the brain and spinal cord. The new research in a mouse model advances earlier work to develop the compound - known as sobetirome - that has already showed promise in stimulating the repair of myelin.

Lead author Priya Chaudhary, M.D., assistant professor of neurology in the OHSU School of Medicine who is focused on developing therapies for neurodegenerative diseases, said that the technique is a common step in drug discovery.

"It is important to show the effectiveness of potential drugs in a model that is most commonly used for developing new therapies," Chaudhary said.

The researchers discovered that they were able to prevent damage to myelin and nerve fibers from occurring, by stimulating a protective response in the cells that make and maintain myelin. They also reduced the activity of migroglia, a type of inflammatory cell in the brain and spinal cord that's involved in causing damage in multiple sclerosis and other diseases.

"The effects are impressive and are at least in part consistent with a neuroprotective effect with particular inhibition of myelin and axon degeneration, and oligodendrocyte loss," the authors write.

The discovery, if proven in clinical trials involving people, could be especially useful for people who are diagnosed with multiple sclerosis early in the disease's progression.

"The drug could protect the nervous system from damage and reduce the severity of the disease," Bourdette said.

 

Does Lamotrigine have the potential to 'cure' Autism?

Recently headlines appeared like this one:-

Scientists 'CURE autism' in mice using $3 epilepsy drug

It referred to the use of the epilepsy drug Lamotrigine to treat a mouse model of autism, caused by reduced expression of the gene MYT1L.

What the tabloid journalists failed to notice was that there has already been a human trial of Lamotrigine in autism.  That trial was viewed as unsuccessful by the clinicians, although the parents did not agree.

There were many comments in the media from parents whose child already takes this drug for their epilepsy and they saw no reduction in autism. There were some who found it made autism worse.

 

MYT1L haploinsufficiency in human neurons and mice causes autism-associated phenotypes that can be reversed by genetic and pharmacologic intervention

 

Lamotrigine therapy for autistic disorder: a randomized, double-blind, placebo-controlled trial

In autism, glutamate may be increased or its receptors up-regulated as part of an excitotoxic process that damages neural networks and subsequently contributes to behavioral and cognitive deficits seen in the disorder. This was a double-blind, placebo-controlled, parallel group study of lamotrigine, an agent that modulates glutamate release. Twenty-eight children (27 boys) ages 3 to 11 years (M = 5.8) with a primary diagnosis of autistic disorder received either placebo or lamotrigine twice daily. In children on lamotrigine, the drug was titrated upward over 8 weeks to reach a mean maintenance dose of 5.0 mg/kg per day. This dose was then maintained for 4 weeks. Following maintenance evaluations, the drug was tapered down over 2 weeks. The trial ended with a 4-week drug-free period. Outcome measures included improvements in severity and behavioral features of autistic disorder (stereotypies, lethargy, irritability, hyperactivity, emotional reciprocity, sharing pleasures) and improvements in language and communication, socialization, and daily living skills noted after 12 weeks (the end of a 4-week maintenance phase). We did not find any significant differences in improvements between lamotrigine or placebo groups on the Autism Behavior Checklist, the Aberrant Behavior Checklist, the Vineland Adaptive Behavior scales, the PL-ADOS, or the CARS. Parent rating scales showed marked improvements, presumably due to expectations of benefits.


One reader of this blog who heard all about the news and was sceptical, since after all it is a mouse model. Her 8 year old non-verbal child was not happy taking the drug Keppra and was already scheduled to try Lamotrigine. 

Within a week his teacher called to say he was saying his ABCs, the next week he was counting out loud, the following month he’s attempting to repeat words of interest and this week he’s spelling animals by memory, dolphin, duck, wolf, chicken, pig, etc.

We are 2 months in and at 50mg, our target dose is 100mg bid. Obviously with our success, I’ve been working with his doctor and will continue to.”

 

Conclusion

Even though every day new autism research is published, there is so much already in this blog that not much appearing is totally new to regular readers.

We saw several years ago that low dose clonazepam should be beneficial to some people with autism, in particular Dravet syndrome. Today we learnt a little more about why Nav1.1 might be disturbed beyond those with Dravet syndrome. In the maternal immune activation model it seems to be a winner. It seems to benefit many of those who have trialed it.

Treating myelination deficits has been well covered in this blog. In previous posts we saw how Pitt Hopkins syndrome researchers showed how myelination gene expression was disturbed in a wide range of autisms. Today we saw evidence to support such therapy and we discovered a new drug.

Oxytocin does help some people with autism, but not as much as you might expect. Today we learnt of a potential add on therapy, a supplement called Maca.

The idea that anti-epilepsy drugs might help some autism has been well covered. From low dose valproate to low dose phenytoin from Dr Philip Bird in Australia.

Treatment of Autism with low-dose Phenytoin, yet another AED

Recent research suggested that Lamotrigine should help some with autism and today you learned that it really does help in one case. The fact that a tiny study a few years ago suggested no responders just tells us that only a small subgroup are likely to benefit.

We already know that some people's autism is made worse by their epilepsy therapy. This is just what you would expect. Time to find a different epilepsy therapy.

My favorite new therapy, low dose mefenemic acid / ponstan has numerous effects. One reader without autism, but with an unusual visual dysfunction (visual snow syndrome) and a sound sensitivity problem contacted me a while to see if NKCC1 might be the root of his problem. I suggested he try Ponstan, which did actually work for him and is easy to buy where he lives. Now he sends me research into all its possible modes of action. One mode of action relates to a cause of intellectual disability (ID/MR). Is this a factor in why Ponstan seems to improve speech and cognition in some autism? I really don't mind why it works - I just got lucky again, that is how I look at it. The more I read the luckier I seem to get.




Wednesday 21 September 2022

Pentoxifylline and cGP (an IGF-1 normalizer) from Blackcurrants, for Autism?

 

 

Readers may be wondering at what point Peter will run out of things to write about.  I do sometimes wonder the same thing. I was going to also write about Loperamide (Imodium), but the post would have been too long. Next time!


Pentoxifylline

Pentoxifylline has been in use to treat autism for 50 years. The original studies did suggest its effect was greatest among small children.  I have been in some discussions with a US psychiatrist, Dr Powell, who is a big fan of the off-label use of this drug to affect the brain in adults.  He has even written a book on the subject.

My previous posts on Pentoxifylline can be found here: 

https://www.epiphanyasd.com/search/label/Pentoxifylline

Dr Powell’s patients with autism tend to be older children, not the toddlers who did well in clinical trials in Japan in the 1970s.  He sees significant improvement in many, but not all, of his patients with autism.  The parents report improved social interactions and having higher-level discussions with their child.

What is notable is that he uses frequent dosing, 4 times a day, always after food to avoid the GI side effects.

Pentoxifylline is inexpensive, but its effect does not last long, hence the frequent dosing.  Some people take taking this drug 5-6 times a day.

Pentoxifylline has multiple modes of action, it should increase blood flow to the brain and it is broadly anti-inflammatory.  It is a non-selective PDE inhibitor, normally used treat muscle pain in people with peripheral artery disease. It increases red blood cell flexibility and it reduces the viscosity of blood.

There are PDEs 1 to 11. It all gets quite complicated, for example PDE1 subtype A2 has a potential role in neurodegenerative diseases, including:

·        Parkinson's disease

·        Axonal neurofilament degradation

·        Motorneuronal degradation

·        Neuronal ischemia

·        Alzheimer's disease

·        Epilepsy

Recall that PDE4 inhibitors are used to treat asthma and COPD. We can potentially repurpose those to improve myelination in MS, or autism, and at specific low doses they can improve cognition.

 

cGP (from Black Currants)

I did write quite a lot in this blog about growth factors and autism.  The familiar ones are BDNF, NGF and IGF-1, but there are many more. 

My previous posts on IGF-1 can be found here: 

https://www.epiphanyasd.com/search/label/IGF-1

We know that growth signaling in autism is disturbed, but it is not simple.  As the disease progresses (the fetus develops, the baby is born and grows into a toddler) the imbalance in growth signaling changes.  This means that what would be helpful in a 6 month old baby might well be inappropriate in a 6 year old.  This is a good example of what I call the what, when and where of treating autism. Here it is the “when” that matters.

Some people lack BDNF while others have too much. Very possibly, this changes over time in the same child.

One possible therapy for autism is injections of IGF-1 (Insulin-like Growth Factor 1).  IGF-1 plays an important role in childhood growth.

A synthetic analog of IGF-1 is used in children for the treatment of growth failure.  This drug called Mecasermin was used in autism trials and in Rett syndrome trials.

In Rett syndrome the search has been on for an oral therapy.

Trofinetide (NNZ-2566) is a potential therapy for Rett syndrome being developed by Neuren Pharmaceuticals in Australia.

Trofinetide is derived from IGF-1.

Trofinetide got to phase 2 trials as a therapy for Fragile-X in 2015.

The second product in development at Neuren is NNZ-2591.  It is aimed at normalizing the level of IGF-1.

This is in the pipeline to treat:

  • Phelan-McDermid syndrome (Shank3 gene and others not working)
  • Angelman syndrome (UBE3A gene not working)
  • Pitt Hopkins syndrome (TCF4 gene not working)
  • Prader-Willi syndrome (MAGEL2 gene and others not working)

https://www.neurenpharma.com/irm/content/product-development-pipeline.aspx?RID=483&RedirectCount=1

 

What is NNZ-2591?

It is an analogue (modified version) of cyclic glycine proline (cGP)

Cyclic glycine-proline (cGP), a metabolite of IGF-1, is neuroprotective through improving IGF-1 function.

There is also research focused on Parkinson’s and Alzheimer’s where it seems that cGP is reduced.

In New Zealand they found that supplementation of Blackcurrant anthocyanins (pigments) increased cGP in the spinal fluid of patients with Parkinson’s.

This also led the way to the idea of increasing cGP as means of protecting the brain during aging. There is now a commercial OTC product in New Zealand to do just this.

Our reader Daniel, who has a daughter with Rett syndrome, is assessing the benefit of cGP, using the OTC product cGPMAX. The results so far are promising.

Rett is very specific because we know for sure that IGF-1 and NGF are disturbed.

Is cGP going to be beneficial in broader autism?  May be yes, but we come back to the what, when and where.  It may well depend on when a specific person takes it.  We have both hypoactive pro-growth signalling autism and hyperactive pro-growth signalling autism.

 

 


Unfortunately, what the clever researchers who came up with the above concept did not consider is that you may start out hyper in the womb and switch to hypo a few short years later.

  

Conclusion

Frequently dosed Pentoxifylline looks like a potentially interesting therapy for many with autism, including some with high IQ.  Take note our Aspie readers.

Daniel’s idea to look at the Neuren’s non-Rett therapy as a Rett therapy is interesting.  In effect you do not need to wait for the Australian drug, you can hop across the Tasman Sea to New Zealand and use their cGP supplement, developed for protection against dementia.

You would also think that parents of children with:

  • Phelan-McDermid syndrome (Shank3 gene and others not working)
  • Angelman syndrome (UBE3A) gene not working)
  • Pitt Hopkins syndrome (TCF4 gene not working)
  • Prader-Willi syndrome (MAGEL2 gene and others not working)

might want to follow Daniel’s lead.

As you can see, there is a lot of trial and error in science.  Back in 2009 NNZ-2566 was in clinical trials for the treatment of cognitive deficits following traumatic brain injury.  That must not have worked out.  Fragile-X did not work out and now it is phase 3 for Rett girls, which seems to be going well.

 

IGF-1 for old people

The same growth factor IGF-1 that is key during development also plays a key role in aging. Dr Jian Guan made a world first discovery. She discovered that cGP (cyclic Glycine-Proline) was responsible for controlling the IGF-1 hormone in our body. Thus by increasing the level of cGP in our body, the cGP will essentially command the IGF-1 to build more blood vessels.

Dr Jian Guan, was then recognised as the world-wide authority on cGP. In 2017 she discovered that New Zealand blackcurrants contained high volumes of natural cGP which could regulate optimum levels of IGF-1 in the body.

So now we have Antipodeans/Kiwis fending off dementia, and potentially metabolic syndrome, by taking their locally made cGPMax.

Will it help you case of autism? Who knows, but if it does not, just give the leftover pills to Grandma, Granddad or take them yourself!

 

All the supporting papers from New Zealand.

https://cgpmax.com/pages/our-science




 

Wednesday 2 February 2022

Genetic Mutations vs Differentially Expressed Genes (DEGs) in Autism

 

Genes make proteins and you need the right amount in the right place
at the right time.

I should start this post by confessing to not having carried out genetic testing on Monty, now aged 18 with autism.  When I did mention this to one autism doctor at a conference, I was surprised by her reply:- “ You did not need to.  Now there’s no point doing it”.

I got lucky and treated at least some of Monty’s Differentially Expressed Genes (DEGs) by approaching the problem from a different direction.

People do often ask me about what diagnostic tests to run and in particular about genetic testing.  In general, people have far too high expectations regarding such tests and assume that there will be definitive answers, leading to effective therapeutic interventions.

I do include an interesting example today where parent power is leading a drive towards an effective therapeutic intervention in one single gene type of autism.  The approach has been to start with the single gene that has the mutation and look downstream at the resulting Differentially Expressed Genes (DEGs). The intervention targets one of the DEGs and not the mutated gene itself.

This is a really important lesson.

It can be possible to repurpose existing drugs to treat DEGs quite cheaply.  Many DEGs encode ion channels and there are very many existing drugs that affect ion channels.

Entirely different types of autism may share some of the same DEGs and so benefit from the same interventions.

 

Genetic Testing 

Genetic testing has not proved to be the holy grail in diagnosing and treating autism, but it remains a worthwhile tool at a population level (i.e. maybe not in your specific case).  What matters most of all are Differentially Expressed Genes (DEGs), which is something different.

A paper was recently published that looked into commercially available genetic testing.  Its conclusion was similar to my belief that you risk getting a “false negative” from these tests, in other words they falsely conclude that there is no genetic basis for the person’s symptoms of autism. 

 

Brief Report: Evaluating the Diagnostic Yield of Commercial Gene Panels in Autism

Autism is a prevalent neurodevelopmental condition, highly heterogenous in both genotype and phenotype. This communication adds to existing discussion of the heterogeneity of clinical sequencing tests, “gene panels”, marketed for application in autism. We evaluate the clinical utility of available gene panels based on existing genetic evidence. We determine that diagnostic yields of these gene panels range from 0.22% to 10.02% and gene selection for the panels is variable in relevance, here measured as percentage overlap with SFARI Gene and ranging from 15.15% to 100%. We conclude that gene panels marketed for use in autism are currently of limited clinical utility, and that sequencing with greater coverage may be more appropriate.

 

To save time and money, the commercial gene panels only test genes that the company defines as autism genes.  There is no approved list of autism genes. 

You have more than 20,000 genes and very many are implicated directly, or indirectly, in autism and its comorbities. To be thorough you need Whole Exome Sequencing (WES), where you check them all.  

There are tiny mutations called SNPs ("snips") which you inherit from your parents; there are more than 300 million known SNPs and most people will carry 4-5 million.  Some SNPs are important but clearly most are not.  Some SNPs are very common and some are very rare. 

Even WES only analyses 2% of your DNA, it does not consider the other 98% which is beyond the exome.  Whole Genome Sequencing (WGS) which looks at 100% of your DNA will be the ideal solution, but at some time in the future.  The interpretation of WES data is often very poor and adding all the extra data from WGS is going to overwhelm most people involved. 

Today we return to the previous theme of treating autism by treating the downstream effects caused by Differentially Expressed Genes (DEGS).

Genetics is very complicated and so people assume that is must be able to provide answers. For a minority of autism current genetics does indeed provide an answer, but for most people it does not.

Early on in this blog I noted so many overlaps between the genes and signaling pathways that drive cancer and autism, that is was clear that to understand autism you probably first have to understand cancer; and who has time to do that!

Some people’s cancer is predictable. Chris Evert, the American former world No. 1 tennis player, announced that she has ovarian cancer.  Her sister had exactly the same cancer.  Examining family history can often yield useful information and it is a lot less expensive that genetic testing.  Most people’s cancer is not so predictable; sure if you expose yourself to known environmental triggers you raise its chances, but much appears to be random.  Cancer, like much autism, is usually a multiple hit process. Multiple events need to occur and you may only need to block one of them to avoid cancer. We saw this with a genetic childhood leukemia that you can prevent with a gut bacteria. 


Learning about Autism from the 3 Steps to Childhood Leukaemia


What is not random in cancer are the Differentially Expressed Genes (DEGs).

We all carry highly beneficial tumor suppressing genes, like the autism/cancer gene PTEN.  You would not want to have a mutation in one of these genes.

What happens in many cancers is that the individual carries two good copies of the gene like PTEN, but the gene is turned off. For example, in many people with prostate cancer, the tumor suppressor gene PTEN is turned off in that specific part of the body.  There is no genetic mutation, but there is a harmful Differentially Expressed Gene (DEG). If you could promptly turn PTEN expression back on, you would suppress the cancer.

Not surprisingly, daily use of drugs that increase PTEN expression is associated with reduced incidence of PTEN associated cancer.  Atorvastatin is one such drug.

 

DEGs are what matter, not simply mutations

 

In many cases genetic mutations are of no clinical relevance, we all carry several on average.  In some cases they are of immediate critical relevance.  In most cases mutations are associated with a chance of something happening, there is no certainty and quite often further hits/events/triggers are required.

A good example is epilepsy. Epilepsy is usually caused by an ion channel dysfunction (sodium, potassium or calcium) that is caused by a defect in the associated gene. Most people are not born with epilepsy, the onset can be many years later.  Some parents of a child with autism/epilepsy carry the same ion channel mutation but remain unaffected. 

 

Follow the DEGs from a known mutation 

There is a vanishingly small amount of intelligent translation of autism science to therapy, or even attempts to do so.  I set out below an example of what can be done.

 

Pitt Hopkins (Haploinsufficiency of TCF4) 

The syndrome is caused by a reduction in Transcription factor 4, due to mutation in the TCF4 gene.  One recently proposed therapy is to repurpose the cheap calcium channel blocker Nicardipine. Follow the rationale below.

 

  means down regulated

↑ means up regulated


1.     Gene/Protein TCF4 (Transcription Factor 4) ↓↓↓↓

2.     Genes SCN10a  ↑↑    KCNQ1 ↑↑

3.     Encoding ion channels  Nav1.8   ↑↑     Kv7.1   ↑↑

4.     Repurpose approved drugs as inhibitors of Kv7.1 and Nav1.8 

5.     High throughput screen (HTS) of 1280 approved drugs.

6.     The HTS delivered 55 inhibitors of Kv7.1 and 93 inhibitors of Nav1.8

7.     Repurposing the Calcium Channel Inhibitor Nicardipine as a Nav1.8 inhibitor 


           

The supporting science: 

Psychiatric Risk Gene Transcription Factor 4 Regulates Intrinsic Excitability of Prefrontal Neurons via Repression of SCN10a and KCNQ1

  

Highlights

•TCF4 loss of function alters the intrinsic excitability of prefrontal neurons 

TCF4-dependent excitability deficits are rescued by SCN10a and KCNQ1 antagonists 

TCF4 represses the expression of SCN10a and KCNQ1 ion channels in central neurons 

•SCN10a is a potential therapeutic target for Pitt-Hopkins syndrome

  

Nav1.8 is a sodium ion channel subtype that in humans is encoded by the SCN10A gene

Kv7.1 (KvLQT1) is a potassium channel protein whose primary subunit in humans is encoded by the KCNQ1 gene.

  

Transcription Factor 4 (TCF4) is a clinically pleiotropic gene associated with schizophrenia and Pitt-Hopkins syndrome (PTHS).  

SNPs in a genomic locus containing TCF4 were among the first to reach genome-wide significance in clinical genome-wide association studies (GWAS) for schizophrenia  These neuropsychiatric disorders are each characterized by prominent cognitive deficits, which suggest not only genetic overlap between these disorders but a potentially overlapping pathophysiology.

We propose that these intrinsic excitability phenotypes may underlie some aspects of pathophysiology observed in PTHS and schizophrenia and identify potential ion channel therapeutic targets.

Given that TCF4 dominant-negative or haploinsufficiency results in PTHS, a syndrome with much more profound neurodevelopmental deficits than those observed in schizophrenia, the mechanism of schizophrenia risk associated with TCF4 is presumably due to less extreme alterations in TCF4 expression at some unknown time point in development

The pathological expression of these peripheral ion channels in the CNS may create a unique opportunity to target these channels with therapeutic agents without producing unwanted off-target effects on normal neuronal physiology, and we speculate that targeting these ion channels may ameliorate cognitive deficits observed in PTHS and potentially schizophrenia.

 

 

Disordered breathing in a Pitt-Hopkins syndrome model involves Phox2b-expressing parafacial neurons and aberrant Nav1.8 expression

Pitt-Hopkins syndrome (PTHS) is a rare autism spectrum-like disorder characterized by intellectual disability, developmental delays, and breathing problems involving episodes of hyperventilation followed by apnea. PTHS is caused by functional haploinsufficiency of the gene encoding transcription factor 4 (Tcf4). Despite the severity of this disease, mechanisms contributing to PTHS behavioral abnormalities are not well understood. Here, we show that a Tcf4 truncation (Tcf4tr/+) mouse model of PTHS exhibits breathing problems similar to PTHS patients. This behavioral deficit is associated with selective loss of putative expiratory parafacial neurons and compromised function of neurons in the retrotrapezoid nucleus that regulate breathing in response to tissue CO2/H+. We also show that central Nav1.8 channels can be targeted pharmacologically to improve respiratory function at the cellular and behavioral levels in Tcf4tr/+ mice, thus establishing Nav1.8 as a high priority target with therapeutic potential in PTHS. 

 

Repurposing Approved Drugs as Inhibitors of Kv7.1 and Nav1.8 To Treat Pitt Hopkins Syndrome

Purpose:

Pitt Hopkins Syndrome (PTHS) is a rare genetic disorder caused by mutations of a specific gene, transcription factor 4 (TCF4), located on chromosome 18. PTHS results in individuals that have moderate to severe intellectual disability, with most exhibiting psychomotor delay. PTHS also exhibits features of autistic spectrum disorders, which are characterized by the impaired ability to communicate and socialize. PTHS is comorbid with a higher prevalence of epileptic seizures which can be present from birth or which commonly develop in childhood. Attenuated or absent TCF4 expression results in increased translation of peripheral ion channels Kv7.1 and Nav1.8 which triggers an increase in after-hyperpolarization and altered firing properties.

Methods:

We now describe a high throughput screen (HTS) of 1280 approved drugs and machine learning models developed from this data. The ion channels were expressed in either CHO (KV7.1) or HEK293 (Nav1.8) cells and the HTS used either 86Rb+ efflux (KV7.1) or a FLIPR assay (Nav1.8).

Results:

The HTS delivered 55 inhibitors of Kv7.1 (4.2% hit rate) and 93 inhibitors of Nav1.8 (7.2% hit rate) at a screening concentration of 10 μM. These datasets also enabled us to generate and validate Bayesian machine learning models for these ion channels. We also describe a structure activity relationship for several dihydropyridine compounds as inhibitors of Nav1.8.

Conclusions:

This work could lead to the potential repurposing of nicardipine or other dihydropyridine calcium channel antagonists as potential treatments for PTHS acting via Nav1.8, as there are currently no approved treatments for this rare disorder.

  

Repurposing the Dihydropyridine Calcium Channel Inhibitor Nicardipine as a Nav1.8 inhibitor in vivo for Pitt Hopkins Syndrome

Individuals with the rare genetic disorder Pitt Hopkins Syndrome (PTHS) do not have sufficient expression of the transcription factor 4 (TCF4) which is located on chromosome 18. TCF4 is a basic helix-loop-helix E protein that is critical for the normal development of the nervous system and the brain in humans. PTHS patients lacking sufficient TCF4 frequently display gastrointestinal issues, intellectual disability and breathing problems. PTHS patients also commonly do not speak and display distinctive facial features and seizures. Recent research has proposed that decreased TCF4 expression can lead to the increased translation of the sodium channel Nav1.8. This in turn results in increased after-hyperpolarization as well as altered firing properties. We have recently identified an FDA approved dihydropyridine calcium antagonist nicardipine used to treat angina, which inhibited Nav1.8 through a drug repurposing screen.

 

All of the above was a parent driven process.  Well done, Audrey!

Questions remain.

Is Nicardipine actually beneficial to people with Pitt Hopkins Syndrome? Does it matter at what age therapy is started? What about the Kv7.1 inhibitor?

 

Conclusion 

Genetics is complicated, ion channel dysfunctions are complicated; but just a superficial understanding can take you a long way to understand autism, epilepsy and many other health issues.

There is a great deal in this blog about channelopathies/ion channel dysfunctions.

https://epiphanyasd.blogspot.com/search/label/Channelopathy

Almost everyone with autism has one or more channelopathies. Most channelopathies are potentially treatable.

Parents of children with rare single gene autisms should get organized and make sure there is basic research into their specific biological condition.  They need to ensure that there is an animal model created and it is then used to screen for existing drugs that may be therapeutic.  I think they also need to advocate for gene therapy to be developed.  This all takes years, but the sooner you start, the sooner you will make an impact.

Very likely, therapies developed for some single gene autisms will be applicable more broadly.  A good example may be the IGF-1 derivative Trofinetide, for girls with Rett Syndrome. IGF-1 (Insulin-like growth factor 1) is an important growth factor that is required for proper brain development. In the brain, IGF-1 is broken down into a protein fragment called glypromate (GPE). Trofinetide is an orally available version of GPE.

The MeCP2 protein controls the expression of several genes, such as Insulin-like Growth Factor 1 (IGF1), brain-derived neurotrophic factor (BDNF) and N-methyl-D-aspartate (NMDA).  All three are implicated in broader autism. 

https://rettsyndromenews.com/trofinetide-nnz-2566/

In girls with Rett Syndrome the genetic mutation is in the gene MeCP2, but one of the key DEGs (differentially expressed genes) is the FXYD1; it is over-expressed. IGF-1 supresses the activity of FXYD1 and hopefully so does Trofinetide.  Not so complicated, after all!

Medicine is often driven by the imperative to do no harm.

In otherwise severely impaired people, perhaps the imperative should be to try and do some good.

In medicine, time is of the essence; doctors in the ER can be heard to say "Stat!", from the Latin word for immediately, statim.  

How about some urgency in translating autism science into therapy? But then, what's the hurry? Why rock the boat?

On an individual basis, much is already possible, but you will have to do most of the work yourself - clearly a step too far for most people.