Big heads, the Car wash, Transcranial pulse stimulation, GABA alpha 5 and Potassium channel Kv3.1

Today’s post is a review of some interesting new research that relates to the scope of this blog.  It ranges from training young people with autism/ID to work at the car wash, to more complex science.

Let’s start with the easiest paper. Somewhat bizarrely it was carried out in Japan by researchers from India. I am a fan of teaching kids to wash cars but I was surprised to see that it would be covered in a published research study.

One often forgotten item to teach teenagers and young adults with autism or ID is how to safely use public transport, so they might travel independently to and from any future job. We have had a lot of success with this recently. Monty, now aged 20, can get all the way from home to various different locations across the city using public transport, including changing buses and with journey times more than one hour.

 

Increasing car washing competency in adolescents with autism and intellectual disabilities: Researching visual task evaluation

This study looked at how well visual task evaluation helped teenagers with autism and intellectual disabilities become more competent at car washing. For disabled people to promote their independence and employment chances, car washing skills are crucial. The goal of this study was to ascertain whether training techniques that include visual task evaluation can improve car washing proficiency in teenagers with autism and intellectual disabilities. 30 participants, ranging in age from 12 to 18, participated in a pre-test/post-test design. Randomly chosen groups of participants were put into the evaluation group for the visual task or the control group. According to the findings, the visual task evaluation group outperformed the control group in terms of car washing ability. Adolescents with autism and intellectual disabilities can learn skills more quickly and become more independent by including visual task evaluation into their teaching strategies. These results demonstrate the potential for such treatments to enhance their quality of life and employment chances.

 

Car washing with a pressure washer is great fun for most people and washing a car thoroughly has many individual steps to master, so it is good practice.

  

Head size

It has been known for decades that big heads (macrocephaly) and small heads (microcephaly) are a tell-tale sign of a neurodevelopment problem. Normally, big heads are linked to intellectual disability, but very small heads are also a warning sign.

Readers may recall the Zika virus epidemic in Brazil in 2015. This mosquito-borne virus caused pregnant women to give birth to children with microcephaly. Zika virus infection caused intellectual disability in babies. The severity of the intellectual disability varied from mild to severe. Babies with Zika virus infection may have difficulty learning and communicating. They may also have problems with problem-solving and abstract thinking. Hearing and vision can be impaired and growth is retarded.  

Head size parts autism into two major subtypes

Essentially opposite paths in fetal brain development may explain two major subtypes of autism. In one of these subtypes, an unusually high number of excitatory neurons in a key brain region leads to large heads, or macrocephaly, which affects roughly 20 percent of people with autism; in the other, a decreased number of the same cells in that area leads to more typical head sizes, a new study finds. 

This fundamental biological difference suggests that “therapeutic avenues may be drastically different for these subtypes,” says lead investigator Flora Vaccarino, professor of neuroscience at Yale University. “That in turn could explain why drug treatments for autism so far are failing.”

 

The opposite brain development paths found in this research may both lead to autism because they are each a case of imbalance, says investigator Alexej Abyzov, associate professor of biomedical informatics at the Mayo Clinic in Rochester, Minnesota. 

The full paper:- 

Modeling idiopathic autism in forebrain organoids reveals an imbalance of excitatory cortical neuron subtypes during early neurogenesis

Idiopathic autism spectrum disorder (ASD) is highly heterogeneous, and it remains unclear how convergent biological processes in affected individuals may give rise to symptoms. Here, using cortical organoids and single-cell transcriptomics, we modeled alterations in the forebrain development between boys with idiopathic ASD and their unaffected fathers in 13 families. Transcriptomic changes suggest that ASD pathogenesis in macrocephalic and normocephalic probands involves an opposite disruption of the balance between excitatory neurons of the dorsal cortical plate and other lineages such as early-generated neurons from the putative preplate. The imbalance stemmed from divergent expression of transcription factors driving cell fate during early cortical development. While we did not find genomic variants in probands that explained the observed transcriptomic alterations, a significant overlap between altered transcripts and reported ASD risk genes affected by rare variants suggests a degree of gene convergence between rare forms of ASD and the developmental transcriptome in idiopathic ASD.

 

Head circumference at birth is a useful measurement, but what really matters is how it changes over time.  Hyperactive pro-growth signaling affects more than just brain growth, it also affects muscle development, which is easy to notice.  I have highlighted the graphic below several times in this blog and in my book.  It is a good summary of what is going on.

 

Kv3.1

Regular readers will know that I like ion channels. The reason is that dysfunctions in these channels really should be treatable.  Usually we are looking for channel blockers, but today with Kv3.1 we are looking for channel enhancers.

Ion channel enhancers increase the activity of ion channels without directly opening them. They do this by increasing the number of open channels, increasing the opening time of each channel, or decreasing the closing time of each channel.

  

Grant aids drug discovery for autism, schizophrenia

At the heart of the study is a type of inhibitory neuron called GABAergic interneurons, which connect brain regions, playing vital roles in coordinating high-frequency brain activity. As a potential source of the excitatory/inhibitory imbalance in ASD and schizophrenia, evidence now points to malfunction of a type of potassium channel, Kv3.1, special to GABAergic interneurons. Denton and his team will aim to develop Kv3.1 enhancers and test their efficacy in restoring the balance of neural activity in a mouse model of ASD. In latter stages of this work, they’ll focus on key brain areas, using various lab techniques to carefully fill in neurological details surrounding any targeted drug effects.

“This grant creates opportunities for developing critically needed tool compounds to explore the role of Kv3.1 potassium channels in autism spectrum disorder and schizophrenia,” said Denton, professor of Anesthesiology and Pharmacology. “These are some of the most challenging and costly disorders going, and we’re excited to have this opportunity to take this work forward.”

 

Japanese researchers from the RIKEN Brain Science Institute are also thinking along the lines of targeting Kv3.1 to “correct aberrant developmental trajectories”. 

K_v3.1 channels regulate the rate of critical period plasticity 

The emergent function of fast-spiking PV-cell circuits during postnatal life may hold the key to a deeper understanding of critical periods in brain development (Reh et al., 2020) and the etiology of related mental illnesses as well (Do KQ and Hensch, 2015). The human neocortex notably shows a decrease in K_v3.1b channel protein in schizophrenia, a deficit that is restored by anti-psychotic drugs (Yanagi et al., 2014). Moreover, individuals with a KCNC1 loss-of-function variant can present intellectual disability without seizure and epilepsy (Poirier et al., 2017; Park et al., 2019). Our work points toward a prophylactic psychiatry that may target these particular channels to correct aberrant developmental trajectories.

 

As with head size, the “when” is also important with correcting Kv3.1.  The idea is to intervene at a very early age to redirect the developmental trajectory, rather than just to improve today’s functioning.

The logical question is what drugs will Professor Denton come up with to explore the benefit of targeting Kv3.1.  Perhaps someone can beat him to it and save us all a couple of decades?

If you look up Kv3.1 or the gene that encodes it called KCNC1 you can read all about it.

https://www.genecards.org/cgi-bin/carddisp.pl?gene=KCNC1

 

As expected, there is no shortage of channel blockers – Nifedipine (used a calcium channel blocker), Miconazole (an antifungal), Capsaicin (an active component of chili peppers), Fluoxetine (better known as Prozac, which is vitamin P to many people) plus many more.

Professor Denton is hunting for a channel enhancer.  Keep an eye on what he comes up with. He has $2.7 million over 4 years to play with. 

 

Transcranial pulse stimulation

Many autism parents do not like drug therapies, but often like the idea of zapping the brain from outside. I liked the idea of Photo biomodulation (PBMT) a form of light therapy that utilizes light sources including lasers or LEDs.

 

Low Level Laser Therapy (LLLT) for Autism – seems to work in Havana

Home/Clinic based Photobiomodulation/Laser Therapy in Autism - acting on Light Sensitive Ion Channels, Mitochondria, Lymph Nodes and more

 

You could potentially do Low Level Laser Therapy (LLLT) at home.

Professor Manual Casanova is a fan of transcranial magnetic stimulation (TMS).

Today’s paper below is about transcranial pulse stimulation, which I suppose we can just call TPS.

Transcranial pulse stimulation (TPS) is a non-invasive brain stimulation technique that uses pulsed electrical or magnetic fields to stimulate the brain. It is a relatively new technique, but it has the potential to be used for a variety of purposes, including:

• Treating neurological disorders such as Parkinson's disease, Alzheimer's disease, and depression
• Enhancing cognitive function, such as memory and attention
• Improving mood and well-being
• Reducing pain
• Promoting neuroplasticity, the ability of the brain to change and adapt

 

 

Effects of transcranial pulse stimulation on autism spectrum disorder: a double-blind, randomized, sham-controlled trial

 

Transcranial pulse stimulation has been proven effective to improve cognition, memory and depressive symptoms of Alzheimer’s disease, but supporting evidence on other neurological diseases or neuropsychiatric disorders remains limited. This study aimed to investigate the effects of transcranial pulse stimulation on the right temporoparietal junction, which is a key node for social cognition for autism spectrum disorder, and to examine the association between transcranial pulse stimulation and executive and social functions. This double-blinded, randomized, sham-controlled trial included 32 participants (27 males), aged 12–17 years with autism spectrum disorder. All eligible participants were randomized into either the verum or sham transcranial pulse stimulation group, on a 1:1 ratio, based on the Childhood Autism Rating Scale screening score. Sixteen participants received six verum transcranial pulse stimulation sessions (energy level: 0.2–0.25 mJ/mm2; pulse frequency: 2.5–4.0 Hz, 800 pulse/session) in 2 weeks on alternate days. The remaining 16 participants received sham transcranial pulse stimulation. The primary outcome measure included Childhood Autism Rating Scale score changes, evaluated by parents, from baseline to 3-month follow-ups. Secondary outcomes included a self-reported questionnaire responded to by parents and cognitive tests responded to by participants. A licensed mental health professional evaluated clinical global impression severity, improvement, efficacy and total score. Results revealed significant interactions in Childhood Autism Rating Scale and other secondary outcomes. Significant group and time effects were found in most secondary outcomes. Additionally, significant differences were found between the transcranial pulse stimulation and sham transcranial pulse stimulation groups in Childhood Autism Rating Scale and clinical global impression improvement and total score immediately after 2 weeks of transcranial pulse stimulation intervention (all P < 0.05), and effects were sustainable at 1- and 3-month follow-up, compared with baseline. The effect size of Childhood Autism Rating Scale (d = 0.83–0.95) and clinical global impression improvement (d = 4.12–4.37) were large to medium immediately after intervention and sustained at 1-month post-stimulation; however, the effects were reduced to small at 3-month post-stimulation (d = 2.31). These findings indicated that transcranial pulse stimulation over right temporoparietal junction was effective to reduce the core symptoms of autism spectrum disorder, as evidenced by a 24% reduction in the total Childhood Autism Rating Scale score in the verum transcranial pulse stimulation group. Additionally, the clinical global impression total score was reduced by 53.7% in the verum transcranial pulse stimulation group at a 3-month follow-up, compared with the baseline. Participants in the verum transcranial pulse stimulation group had shown substantial improvement at 1- and 3-month follow-ups, compared with baseline, although some of the neuropsychological test results were deemed statistically insignificant. Future replication of this study should include a larger sample derived from multi-nations to determine transcranial pulse stimulation as an alternative top-on treatment option in neuropsychiatry

 

TPS looks pretty impressive, based on the above study. TPS is available today, but it does need a lot of visits to the therapist. The effects are not permanent so you would have to keep going back for more.

People are doing transcranial direct current stimulation (tDCS) at home. 

People are zapping their brains at home to improve focus and clear brain fog. But is it safe?

For any kind of zapping therapy to be viable, it would have to be possible to do it yourself at home.

 

Targeting alpha 5 subunit of GABA_A receptors

Some earlier posts in this blog did get rather complicated.  One field that I looked at in rather painful detail was the GABA_A receptor. Some readers of this blog have children whose autism is entirely caused by a defect in this receptor, many other readers just see the effects of a GABA_A malfunction caused by a problem with NKCC1/KCC2 expression resulting from the GABA developmental switch failing to occur.

I looked to me that targeting alpha 3 and alpha 5 subunits could well enhance cognition.

Alpha 3 is targeted by low dose Clonazepam, thanks to Professor Catterall.

Alpha 5 was targeted to treat Down syndrome, using a new drug called Basmisanil (an inverse agonist of alpha 5 subunit of GABA_A). That work failed. I wrote about Cardiazol/ Pentylenetetrazol (PTZ) a drug that was widely used in the 1930s in mental hospitals to trigger seizures that were supposed to treat people with schizophrenia.  At much lower doses, it found a new purpose decades ago as an ingredient in cough medicine. 

The alpha 5 subunit is one of several subunits that can make up a GABA_A receptor. GABA_A receptors containing the alpha 5 subunit are thought to be involved in cognitive function, learning and memory, and mood regulation.

PTZ has been shown to block the action of GABA at alpha 5-containing GABAa receptors in animal studies.  

Variable Expression of GABRA5 and Activation of α5 -  a Modifier of Cognitive Function in Autism?

 

Sodium Benzoate and GABRA5 - Raising Cognitive Function in Autism 

Cardiazol, a failed Schizophrenia treatment from the 1930s, repurposed at low doses as a Cognitive Enhancer in Down Syndrome and likely some Autism

 

The logical human trial would be to use the cough mixture, Cardiazole that is already used in children. 

“We actual have quite a few readers from India and that is the only other country using this drug.  In India the producer is Nicholas Piramal and the brand name is Cardiazol Dicodid, it cost 30 US cents for 10ml.  So for less than $1, or 70 rupees, you might have a few months of cognitive enhancement, that is less than some people pay for 1 minute of ABA therapy.

If a few drops of this children’s cough medicine improves cognition please lets us all know.”

 

Back to recent research on alpha 5 that caught my attention.

 

An alpha 5-GABAa receptor positive allosteric modulator attenuates social and cognitive deficits without changing dopamine system hyperactivity in an animal model for autism

 Autism Spectrum Disorders (ASD) are characterized by core behavioral symptoms in the domains of sociability, language/communication, and repetitive or stereotyped behaviors. Deficits in the prefrontal and hippocampal excitatory/inhibitory balance due to a functional loss of GABAergic interneurons are proposed to underlie these symptoms. Increasing the postsynaptic effects of GABA with compounds that selectively modulate GABAergic receptors could be a potential target for treating ASD symptoms. In addition, deficits in GABAergic interneurons have been linked to dopamine (DA) system dysregulation, and, despite conflicting evidence, abnormalities in the DA system activity may underly some ASD symptoms. Here, we investigated whether the positive allosteric modulator of α5-containing GABA_A receptors (α5-GABA_ARs) SH-053-2’F-R-CH3 (10 mg/kg) attenuates behavioral abnormalities in a rat model for autism based on in utero VPA exposure. We also evaluated if animals exposed to VPA in utero present changes in the ventral tegmental area (VTA) DA system activity using in vivo electrophysiology and if SH-053-2’F-R-CH3 could attenuate these changes. In utero VPA exposure caused male and female rats to present increased repetitive behavior (self-grooming) in early adolescence and deficits in social interaction in adulthood. Male, but not female VPA rats, also presented deficits in recognition memory as adults. SH-053-2’F-R-CH3 attenuated the impairments in sociability and cognitive function in male VPA-exposed rats without attenuating the decreased social interaction in females. Male and female adult VPA-exposed rats also showed an increased VTA DA neuron population activity, which was not changed by SH-053-2’F-R-CH3. Despite sex differences, our findings indicate α5-GABA_ARs positive allosteric modulators may effectively attenuate some core ASD symptoms

 

Fine tuning alpha 5, perhaps you need more, perhaps less?

 

Neurobiology and Therapeutic Potential of α5-GABA Type A Receptors

Despite being a genetically heterogeneous disorder, the potential utility for mechanism-based GABAAR pharmacologic treatment with ASDs is supported by shared pathologies both in patients and related mouse models.

  

PAM α5 GABAAR Therapeutic Applications

Neurodevelopmental Disorders

Mouse models of neurodevelopmental disorders that present with insufficient inhibitory tone show improvement with positive modulators of GABAAR signaling. In the Scn1a+/− mouse model of Dravet syndrome, a severe childhood epileptic encephalopathy syndrome with hyperactivity and autism behaviors, abnormal social behaviors and fear memory deficits were rescued following treatment with a benzodiazepine, clonazepam (Han et al., 2014). In an ASD mouse model with reduced GABAAR-mediated inhibition, the BTBR T+tf/J mouse, the α2,3 and 5 PAM L-838,417, improved deficits in social interaction, repetitive behaviors, and spatial learning (Han et al., 2014).

 

Postweaning positive modulation of α5GABAA receptors improves autism‐like features in prenatal valproate rat model in a sex‐specific manner 

Autism spectrum disorder (ASD), as a common neurodevelopmental disorder that encompasses impairments in social communication and interaction, as well as repetitive and restrictive behavior, still awaits an effective treatment strategy. The involvement of GABAergic neurotransmission, and especially a deficit of GABA A receptors that contain the α5 subunits, were implicated in pathogenesis of ASD. Therefore, we tested MP‐III‐022, a positive allosteric modulator (PAM) selective for α5GABAA receptors, in Wistar rats prenatally exposed to valproic acid, as an animal model useful for studying ASD. Postweaning rats of both sexes were treated for 7 days with vehicle or MP‐III‐022 at two doses pharmacokinetically determined as selective, and thereafter tested in a behavioral battery (social interaction test, elevated plus maze, spontaneous locomotor activity, and standard and reverse Morris water maze). Additional rats were used for establishing a primary neuronal culture and performing calcium imaging, and determination of hippocampal mRNA levels of GABRA5, NKCC1, and KCC2. MP‐III‐022 prevented impairments in many parameters connected with social, repetitive and restrictive behavioral domains. The lower and higher dose was more effective in males and females, respectively. Intriguingly, MP‐III‐022 elicited certain changes in control animals similar to those manifested in valproate animals themselves. Behavioral results were mirrored in GABA switch and spontaneous neuronal activity, assessed with calcium imaging, and also in expression changes of three genes analyzed. Our data support a role of α5GABAA receptors in pathophysiology of ASD, and suggest a potential application of selective PAMs in its treatment, that needs to be researched in a sex‐specific manner. Lay Summary In rats prenatally exposed to valproate as a model of autism, a modulator of α5GABAA receptors ameliorated social, repetitive and restrictive impairments, and, intriguingly, elicited certain autism‐like changes in control rats. Behavioral results were mirrored in GABA switch and spontaneous neuronal activity, and partly in gene expression changes. This shows a role of α5GABAA receptors in pathophysiology of ASD, and a potential application of their selective modulators in its treatment.

 

Note the researchers actually know about the GABA switch and so measured mRNA levels of NKCC1 and KCC2.

Note also that the lower dose of MP‐III‐022 was more effective in males and the higher dose in females.

We even have the recent associated PhD thesis from Anja Santrač:-

 

The influence of positive modulation of GABAA receptors containing the alpha5 subunit on behavioral changes of mice and rats in models of autistic disorders

The role of α5 GABAA receptors in learning and memory is well known. Therefore, we decided to examine the effect of the selective positive allosteric modulator (PAM) MP-III-022 on learning and memory of healthy animals, as well as GABRA5 expression. After demonstrating the needed tolerability and potential procognitive effects, the ligand would be used in an animal model of autism spectrum disorders (ASD). ASD is a neurodevelopmental disorder that encompasses impairments in social communication and interaction, as well as repetitive and restrictive behavior, still without an effective treatment. In this context, animal models that imitate specific disease’s symptoms are an excellent tool of translational research. Some of the most frequently used models are BTBR T+ tf/J mouse strain (BTBR) and valproate prenatal model (VPA). Our experiments have shown that the variability of α5GABAA receptors’ roles depends on its level of expression and localization, on the type and protocol of cognitive tasks, the timing of testing and intensity of pharmacological modulation. Obtained results proved potential beneficial effects of MP-III-022 in cognitive tasks. The BTBR model failed to express sufficient face validity, while VPA demonstrated adequate face validity and in part construct validity. Thus, we decided to subacutely apply MP-III-022 to juvenile VPA rats. In control animals, treatment led to GABRA5 decrease and to impairments similar to ones seen in ASD, suggesting the possible role of this receptor in the pathogenesis of the disease. Most importantly, our results demonstrated the potential of α5 GABAA receptor PAMs in secondary prevention and treatment of ASD, with the caveat that the drug development program would require adaptations tailored to sex-specific differences revealed.

 

Good job Anja. For our Serbian speaking readers, here is the link to her thesis:-

https://nardus.mpn.gov.rs/bitstream/handle/123456789/21424/Disertacija_13513.pdf?sequence=1&isAllowed=y

Perhaps we should connect her with Professor Ben-Ari?

  

Conclusion

Fine tuning alpha 5 subunits of GABA_A receptors really should be followed up.  I think you need both options - a little bit more and a little bit less. It did not work for Roche in Down syndrome, but the potential remains.

Kv3.1 is another focused target for research, that very likely will become actionable. 

Transcranial pulse stimulation, like all the other zapping therapies, looks interesting, but it needs to be packaged in way that can actually be implemented every day at home.

In the meantime, at least getting your kid to wash the car is something we can all do.