Chlorzoxazone for sound sensitivity (hyperacusis) and hyper-excitable neural circuits in Fragile X and broader autism – an alternative to Ponstan? Why is Gallic acid beneficial in Autism? Varenicline and other nicotinic therapies, revisited

  

 

Today’s post covers some practical interventions raised recently either in the research, or in the comments section.

 

·         Chlorzoxazone (via Potassium channels – BKCa, SKCa) an old muscle relaxant first approved in 1958

·         Varenicline a drug approved in 2006 that targets nicotinic receptors in the brain

·         Nicotine

·         Tropisetron, an anti-nausea drug that also targets nicotinic receptors in the brain; it was approved in 1992 in Switzerland and is available in the Europe but not the US.

·         Gallic acid, a component of numerous plants/foods (grapes, pomegranates, green tea, red wine etc) that have been used in traditional medicine across different cultures

 

The common link between the first four is the sensory problems usually found across all severities of autism, and some forms of ADHD/autism-lite. It can be either sound sensitivity (hyperacusis) or misophonia (impaired sensory gating), both of which often co-occur in the same person.

We will refer to some of the excellent research into Fragile X syndrome. This is the most common single gene type of autism; most autism is polygenic and some is not of genetic origin at all (hypoxia during birth, sepsis etc).

 

Let’s start with the easiest topic.

 

Gallic acid

I saw the recent study below and wondered what is gallic acid.

 

Vitamin C and Gallic Acid Ameliorate Motor Dysfunction, Cognitive Deficits, and Brain Oxidative Stress in a Valproic Acid‐Induced Model of Autism

Autism, a developmental‐neurodegenerative disorder, often manifests as social communication difficulties and has been correlated to oxidative stress in the brain. Vitamins C and gallic acid (GA) possess potent antioxidant properties, making them potential candidates for addressing autism‐related issues. This study examined the influence of vitamin C (Vit C) and GA on behavioral, motor, and cognitive performance, along with the assessment of brain oxidative markers, using an experimental model of autism.

Finding

The prenatal VPA‐induced autism model increased nociceptive threshold, heightened anxiety‐like behaviors, impaired balance power, delayed spatial learning, elevated malondialdehyde, and decreased glutathione and catalase levels in the brains of the male offspring. Administration of Vit C and GA effectively mitigated these anomalies.

Conclusions

Vit C and GA could potentially alleviate anxiety‐like behaviors, motor and cognitive deficits, and brain oxidative stress markers in a prenatal rat autism model. This underscores their viability as potential pharmacological interventions for treating autistic dysfunction.

 

Gallic acid is a naturally occurring organic acid widely found in various plants, fruits, and foods. It is notable for its antioxidant, anti-inflammatory, and antimicrobial properties, making it of interest in health and medicine.

For no obvious reason, gallic acid has never been commercialized as a supplement, but gallic acid is one of the reasons a glass of red wine a day may well be good for you.  It can give a you a 20 mg dose of gallic acid.

Red wines made from grape varieties with higher tannin content, such as Cabernet Sauvignon or Pinot Noir, tend to have higher levels of gallic acid because tannins contain gallic acid. Longer aging, especially in oak barrels, can increase gallic acid due to the extraction from the wood.

The new study suggests that gallic acid is a potential pharmacological intervention for treating autism.  It joins an already very long list! 

 

Varenicline and other nicotinic therapies

Our reader Dragos in Romania recently asked for help obtaining Varenicline, which is also sold as Chantix. This drug is similar to using a nicotine patch, but different in some important ways.

DAN doctors in the US used to prescribe nicotine patches to children with autism.

There is a lot of research to support the use  of therapies that target a specific nicotinic receptor in the brain called the alpha 7 nicotinic acetylcholine receptor (α7 nAChR).

Nicotine itself activates all nicotinic receptors, not just α7 nAChR.

Dragos want to trial the smoking cessation drug Varenicline, which targets α7 nAChRs and a little bit the one called α4β2 nAChR.

 

α7 nAChRs

These receptors are well known to be implicated in diseases such as Alzheimer's, schizophrenia, autism, and epilepsy.

They affect:

Cognition and memory

·        α7 nAChRs are involved in synaptic plasticity, learning, and memory formation due to their role in calcium signaling and modulation of neurotransmitter release.

·        Highly expressed in the hippocampus, which is critical for memory processing.

Neuroprotection

·        Calcium influx through α7 nAChRs activates signaling pathways that promote cell survival and neuroprotection.

·        Involved in reducing neuroinflammation and protecting against excitotoxicity.

Modulation of Neurotransmitter Release

·        Regulate the release of dopamine, glutamate, GABA, and serotonin, impacting mood, arousal, and reward mechanisms.

Inflammatory Regulation

·        Present on immune cells, where they regulate the release of pro-inflammatory cytokines like TNF-α via the cholinergic anti-inflammatory pathway.

Sensory Gating

·        α7 nAChRs are crucial for sensory filtering, preventing sensory overload. Dysfunction in these receptors is linked to conditions like autism and schizophrenia.

 

α4β2 nAChRs

These play a role in:

Cognitive function

·        Involved in attention, learning, and memory.

·        Enhances synaptic plasticity in brain regions like the hippocampus.

Dopamine release

Pain modulation

Mood regulation

 

Research has shown reduced expression of both α7 nAChRs and α4β2 nAChRs in the brains of people with autism.

Dragos has good reason to trial Varenicline; not only has another young adult in Romania with severe autism recently responded well, but there are published case reports to give further support.

 

Varenicline in Autism: Theory and Case Report of Clinical and Biochemical Changes

Objective: To explore the potential benefits of varenicline (CHANTIX^®), a highly specific partial agonist of neuronal α4β2 nicotinic acetylcholine receptors (nAChR), for autistic symptoms, and present resulting biochemical changes in light of dopamine-related genotype.

Methods: The clinical and biochemical changes exhibited by a 19-year-old severely autistic man following the use of low-dose varenicline in an ABA experiment of nature, and his genotype, were extracted from chart review. Clinical outcome was measured by the Ohio Autism Clinical Impression Scale and 12 relevant urine and saliva metabolites were measured by Neuroscience Laboratory.

Results: With varenicline, this patient improved clinically and autonomic biochemical indicators in saliva and urine normalized, including dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), epinephrine, norepinephrine, taurine, and histamine levels. In addition, with varenicline, the dopamine D1 receptor (DRD1) antibody titer as well as the percent of baseline calmodulin-dependent protein kinase II (CaM KII) activity dropped significantly. When varenicline stopped, he deteriorated; when it was resumed, he again improved. Doses of 0.5, 1, and 2 mg daily were tried before settling on a dose of 1.5 mg daily. He has remained on varenicline for over a year with no noticeable side effects.

Conclusion: This report is, to the best of our knowledge, only the second to demonstrate positive effects of varenicline in autism, the first to show it in a severe case, and the first to show normalization of biochemical parameters related to genotype. As with the previous report, these encouraging results warrant further controlled research before clinical recommendations can be made.

 

Varenicline vs Nicotine 

Let’s compare the mechanisms of action:

Varenicline

• Partial agonist at the α4β2 nicotinic acetylcholine receptor (nAChR) and a full agonist at α7 nAChRs.
• Modulates neurotransmitter release (e.g., dopamine, glutamate), which may improve cognitive function and reduce repetitive behaviors in ASD.
• FDA-approved for smoking cessation.

 

Nicotine Patches

• Deliver nicotine, a full agonist at nAChRs.
• Broadly activate multiple nAChR subtypes, leading to enhanced cholinergic signaling.
• Typically used for smoking cessation

 

Other Considerations

Varenicline

·         Offers more targeted modulation of nAChRs with less widespread cholinergic activation.

• Varenicline’s mechanism prevents full desensitization, maintaining its effects over time.

·         May be preferred if minimizing side effects like overstimulation is important.

 

Nicotine Patches:

• Easy to administer and widely available but less specific in its action, which may lead to more off-target effects.
• Nicotine can lead to rapid receptor desensitization and tolerance, especially with continuous delivery via patches.

 

Alternatives

There are some theoretical alternatives, such as:

 

ABT-126 (Pozanicline)

·         Type: Selective α7 nAChR agonist.

·         Status: Investigated for Alzheimer's disease and schizophrenia.

·         Cognitive enhancement and improved sensory gating.

 

RG3487 (MEM 3454)

·         Type: Partial α7 nAChR agonist and modulator of glutamate receptors.

·         Status: Investigated for schizophrenia and cognitive impairment.

·      Improves cognition and reduces symptoms like sensory gating deficits.

 

The one that caught my attention previously when writing about this subject was Tropisetron.

 

Tropisetron:

• Already approved as an antiemetic but also acts as a weak α7 nAChR agonist.
• Potential benefits in cognitive and inflammatory disorders.

 

Clinical Evidence with Tropisetron

Schizophrenia

Early studies show cognitive and sensory gating improvements in schizophrenia patients treated with tropisetron.

One-day tropisetron treatment improves cognitive deficits and P50 inhibition deficits in schizophrenia

Not to forget Vagus Nerve Stimulation (VNS)

The vagus nerve activates α7 nAChRs on immune cells, reducing inflammation without immunosuppression.

The vagus nerve indirectly affects α7 and α4β2 nAChRs in the brain by modulating acetylcholine release.

Vagus nerve stimulation is already used in epilepsy, depression, and inflammatory disorders.

 

It is worthwhile highlighting the effect on people with some types of GI disorder. There is a known association between Asperger’s and ulcerative colitis.

 

Nicotine and Ulcerative Colitis (UC)

·         Smoking appears to have a protective effect on ulcerative colitis.

·         Smokers are less likely to develop UC, and those who quit smoking are at higher risk of developing the condition.

·         Current smokers with UC may experience milder disease with fewer flares and less severe symptoms.

The suggested mechanism

·         Dysregulated inflammation in the colonic mucosa leads to ulcerations, diarrhea, and abdominal pain.

·         α7 nAChR activation may reduce this inflammation, aiding in mucosal healing and symptom improvement.

·         Nicotine’s anti-inflammatory effects may play a role by modulating cytokine release (e.g., reduced IL-8 and TNF-α).

·         Nicotine also stimulates mucus production and increases colonic blood flow, potentially improving mucosal healing.

·         Smoking-induced changes in the microbiome may also reduce UC severity.

 

Note that for Crohn's Disease (CD) and Irritable Bowel Syndrome (IBS) smoking makes the symptoms worse.

 

So, it would make sense to use vagal nerve stimulation for inflammatory bowel disease?

 

Here are results from 2023

 

Vagus nerve stimulation reduces inflammation in children with inflammatory bowel disease

 

Bioelectronic medicine researchers at The Feinstein Institutes for Medical Research and Cohen Children’s Medical Center published results today, in the journal Bioelectronic Medicine, from a proof-of-concept clinical trial that showed non-invasive, non-pharmacological transcutaneous auricular vagus nerve stimulation (ta-VNS), or stimulating in the ear, significantly reduced inflammation in more than 64 percent of pediatric patients with IBD. 

Dr. Sahn and his team used a commercially available transcutaneous electrical nerve stimulator (TENS) unit (TENS 7000) and sensor probe for the trial. Two earbuds on the probes were placed on a small area of the external ear called the cymba conchae, where the vagus nerve is most accessible. For five-minute intervals, the patients received the stimulation for a total of 16 weeks.

 Finally to BKCa and SKCa channels in Fragile X syndrome (FXS) and broader autism !

 

Let’s have a quick recap on Fragile X.

 

Fragile-X

Fragile X (FXS) is the most common single gene cause of intellectual disability (IQ less than 70).

FXS affects approximately 1 in 4,000 males and 1 in 8,000 females.

The condition is very well studied and the Fragile X gene (FMR1) is considered an autism gene.

I am surprised how rarely (never?) FXS parents comment in this blog. They are actually the ones who stand to benefit the most, given how well-studied their syndrome is and how many treatment options exist. I was recently discussing this exact point with an autism therapist with an FXS patient – why do parents remain passive and not react?

 

More severe in males than females

Males have one copy of the FMR1 gene, while females have two.

In females with the full mutation, symptoms are generally less severe than in males due to what is called random X-inactivation. Since females have two X chromosomes, one of the X chromosomes in each cell is randomly inactivated. In cells where the X with the mutation is inactivated, FMRP is produced normally, and in cells where the normal X is inactivated, no FMRP is produced. The severity of symptoms often correlates with the proportion of cells in which the mutated X is active.

In a strange twist of fate females with the milder form of FXS, called premutation, have the greatest chance of being infertile. This is due to Fragile X-associated primary ovarian insufficiency (FXPOI).

 

Testing

The ability to conduct genetic testing began in the 1990s, became more widespread by the mid-1990s, and became integrated into routine clinical practice in the early 2000s. Today, genetic testing for Fragile X is a standard tool used to diagnose FXS, assess carrier status, and inform genetic counselling.

You can also identify Fragile X based on facial features and this is a common practice, especially in the early diagnosis of individuals with the syndrome.

BKCa and SKCa channels in autism and Fragile X

Ion channel dysfunctions play a key role in all neurological conditions. A great deal is known about them, making them an excellent target for intervention.

Fragile X is such a well-studied condition that you can access all the information very easily.

For other single gene autisms and the more common idiopathic (unknown cause) autism it is more a matter of guesswork. 

This recent paper is excellent: 

Channelopathies in fragile X syndrome

The paper lists all the proven ion channel dysfunctions and suggests how to treat some of them.

Potassium channels – BKCa, SKCa, Kv1.2, Kv3.1, Kv4.2,

Calcium channels – Cav1.3, Cav2.1, Cav2.3,

Misc – HCN, NKCC1, AMPAR, NMDAR, GABA_AR

 

Targeting BKCa, SKCa in Fragile X and for hyperacusis in broader autism

In FXS, hyperexcitability in brain circuits is thought to contribute to cognitive and behavioral symptoms.

Preclinical studies suggest that SKCa and BKCa channel activators may correct this hyperexcitability and improve neural network function.

The therapeutic effects of a cheap drug called chlorzoxazone in FXS models are believed to stem from its ability to enhance BKCa channel activity. These channels play a pivotal role in regulating neuronal firing rates and neurotransmitter release. By activating BKCa channels, chlorzoxazone may counteract the neuronal hyperexcitability observed in FXS, leading to improved behavioral and sensory outcomes.

BKCa channels are indispensable for hearing, as they regulate frequency tuning, temporal precision, and signal transmission in both cochlear hair cells and auditory neurons. Dysfunctions in these channels are linked to hearing impairments like frequency discrimination deficits, tinnitus, and hyperacusis (sound sensitivity). Modulating BKCa activity offers a promising avenue for treating auditory disorders.

 

Therapeutic efficacy of the BKCa channel opener chlorzoxazone in a mouse model of Fragile X syndrome

Fragile X syndrome (FXS) is an X-linked neurodevelopmental disorder characterized by several behavioral abnormalities, including hyperactivity, anxiety, sensory hyper-responsiveness, and autistic-like symptoms such as social deficits. Despite considerable efforts, effective pharmacological treatments are still lacking, prompting the need for exploring the therapeutic value of existing drugs beyond their original approved use. One such repurposed drug is chlorzoxazone which is classified as a large-conductance calcium-dependent potassium (BKCa) channel opener. Reduced BKCa channel functionality has been reported in FXS patients, suggesting that molecules activating these channels could serve as promising treatments for this syndrome. Here, we sought to characterize the therapeutic potential of chlorzoxazone using the Fmr1-KO mouse model of FXS which recapitulates the main phenotypes of FXS, including BKCa channel alterations. Chlorzoxazone, administered either acutely or chronically, rescued hyperactivity and acoustic hyper-responsiveness as well as impaired social interactions exhibited by Fmr1-KO mice. Chlorzoxazone was more efficacious in alleviating these phenotypes than gaboxadol and metformin, two repurposed treatments for FXS that do not target BKCa channels. Systemic administration of chlorzoxazone modulated the neuronal activity-dependent gene c-fos in selected brain areas of Fmr1-KO mice, corrected aberrant hippocampal dendritic spines, and was able to rescue impaired BKCa currents recorded from hippocampal and cortical neurons of these mutants. Collectively, these findings provide further preclinical support for BKCa channels as a valuable therapeutic target for treating FXS and encourage the repurposing of chlorzoxazone for clinical applications in FXS and other related neurodevelopmental diseases.

  

·        Chlorzoxazone

In the FXS research they repurpose a drug called chlorzoxazone to activate BKCa channels, with positive results

 

·        Mefenamic acid (Ponstan)

In this blog Ponstan has shown promise to treat hyperacusis. Ponstan is a known activator of both BKCa and SKCa channels.

 

Which is “better” chlorzoxazone or Ponstan?

According to the science chlorzoxazone is more potent than Ponstan in affecting both BKCa and SKCa channels.

Ponstan has more effects on Kv channels like Kv7. Kv7 is implicated in autism and epilepsy.

In terms of gene expression Ponstan has more direct effects on gene expression due to its modulation of inflammatory pathways and inhibition of prostaglandin synthesis.

Chlorzoxazone primarily acts on ion channels, and its effects on gene expression are secondary and less pronounced.

In conclusion the two drugs are very different, both potentially useful, and some of their actions, such as on hyperacusis, are overlapping.

  

Conclusion

Chlorzoxazone an inexpensive drug used to treat muscle spasms is also known for its effects on calcium-activated potassium channels (BKCa and SKCa).

Some claim that Chlorzoxazone may affect GABAa and/or GABAb receptors, but that appears not to be the case.

The research suggests that Chlorzoxazone should have a beneficial effect in FXS and very likely would have a benefit in some broader autism and in hyperacusis specifically.

The effects of Chlorzoxazone are likely to overlap with the effects of Ponstan. Ponstan is quite possibly also going to be effective in FXS, as it is in broader autism.

There are many suggested therapies for FXS (Metformin, Lovastatin, Baclofen, Acamprosate, Gabapentin, Minocycline, Memantine, Rapamycin, L-carnitine, Omega 3 etc). None, when taken alone, are game-changers.

Every parent of a child with Fragile X should read the paper I have linked to in this post.

 

Channelopathies in fragile X syndrome

 

It is full of excellent ideas. If NKCC1 is overexpressed, as is suggested, trial bumetanide.

As in all autism, polytherapy is going to be key. No single therapy can be highly effective with so many dysfunctions present. To quote from the above paper:-

 “Ultimately, the most effective treatment strategies are likely to be multifactorial.”

This means do not be surprised if you need 5 different drugs, with 5 different targets to produce a game-changing effect. Better 5 cheap old re-purposed generic drugs than a single brand-new drug with little overall effect and that costs a king’s ransom, each and every year.

Unfortunately, a personalized approach will need to be used to find such a polytherapy. What works at one age may not be beneficial at another age. Even within single gene autisms, treatment response can vary widely from person to person.

At a conference, I did ask a clinician who is an “expert” in Fragile X, does she apply any of the existing therapies from the research, to her patients. She was rather taken aback by the idea and said “no, we have to follow the protocols.” So, an expert in exactly what then? An expert would make the protocols, if none existed.

Maternal Agmatine or Choline to prevent autism? International brain pH project. Androgen levels in autism spectrum disorders. Apigenin works for BTBR mice. Auditory hypersensitivity, myelin and Nav1.2 channels. Dopamine transporter binding abnormalities and self-injury

 

Shutting the stable door after the horse has bolted

Today’s post is a summary of what I found interesting in the latest research.  Many items have been touched on previously.

The topic of maternal treatment to prevent future autism did come up in some recent comments on this blog. Two of the recent papers cover this very subject. One uses agmatine, from my autism PolyPill therapy, while the other used choline.

Auditory sound sensitivity is a complex subject and today we see the potential role impaired myelination and Nav1.2 ion channels can play.

A Chinese study reconfirms the elevated level of androgen hormones in autism.  

Apigenin which was covered in an earlier post is shown to help “autistic” mice in the popular BTBR model. This is a model where the corpus callosum is entirely absent.

Self-injury is a recuring nightmare for many with severe autism and today we look at a possible correlation with dopamine transporter binding abnormalities.

We start with easier subject matter and leave the hard parts for later in the post.

Preventing future autism

It may seem like too late to be talking about preventing autism, but it is a recurring subject. Today we have two new ideas that have appeared in the literature, and both are very simple. One is choline and other agmatine; both are used in the treatment of already existing autism.

 

Maternal choline to prevent autism

“maternal choline supplementation may be sufficient to blunt some of the behavioral and neurobiological impacts of inflammatory exposures in utero, indicating that it may be a cheap, safe, and effective intervention for neurodevelopmental disorders.” 

 

Maternal choline supplementation modulates cognition and induces anti-inflammatory signaling in the prefrontal cortex of adolescent rats exposed to maternal immune activation

Maternal infection has long been described as a risk factor for neurodevelopmental disorders, especially autism spectrum disorders (ASD) and schizophrenia. Although many pathogens do not cross the placenta and infect the developing fetus directly, the maternal immune response to them is sufficient to alter fetal neurodevelopment, a phenomenon termed maternal immune activation (MIA). Low maternal choline is also a risk factor for neurodevelopmental disorders, and most pregnant people do not receive enough of it. In addition to its role in neurodevelopment, choline is capable of inducing anti-inflammatory signaling through a nicotinic pathway. Therefore, it was hypothesized that maternal choline supplementation would blunt the neurodevelopmental impact of MIA in offspring through long- term instigation of cholinergic anti-inflammatory signaling.

To model MIA in rats, the viral mimetic polyinosinic:polycytidylic acid (poly(I:C)) was used to elicit a maternal antiviral innate immune response in dams both with and without choline supplementation. Offspring were reared to both early and late adolescent stages (postnatal days 28 and 50, respectively), where cognition and anxiety-related behaviors were examined. After behavioral testing, animals were euthanized, and their prefrontal cortices (PFCs) were collected for analysis. MIA offspring demonstrated sex-specific patterns of altered cognition and repetitive behaviors, which were modulated by maternal choline supplementation. Choline supplementation also bolstered anti-inflammatory signaling in the PFCs of MIA animals at both early and late adolescent stages. These findings suggest that maternal choline supplementation may be sufficient to blunt some of the behavioral and neurobiological impacts of inflammatory exposures in utero, indicating that it may be a cheap, safe, and effective intervention for neurodevelopmental disorders.

 

Prenatal Agmatine to prevent autism

Agmatine is a cheap bodybuilder supplement also used in psychiatry that has been extensively covered in this blog. Here we see how in a popular mouse model it can prevent autism.

The prenatal use of agmatine prevents social behavior deficits in VPA-exposed mice by activating the ERK/CREB/BDNF signaling pathway

Background: According to reports, prenatal exposure to valproic acid can induce autism spectrum disorder (ASD)-like symptoms in both humans and rodents. However, the exact cause and therapeutic method of ASD is not fully understood. Agmatine (AGM) is known for its neuroprotective effects, and this study aims to explore whether giving agmatine hydrochloride before birth can prevent autism-like behaviors in mouse offspring exposed prenatally to valproic acid.

Methods: In this study, we investigated the effects of AGM prenatally on valproate (VPA)-exposed mice. We established a mouse model of ASD by prenatally administering VPA. From birth to weaning, we evaluated mouse behavior using the marble burying test, open-field test, and three-chamber social interaction test on male offspring.

Results: The results showed prenatal use of AGM relieved anxiety and hyperactivity behaviors as well as ameliorated sociability of VPA-exposed mice in the marble burying test, open-field test, and three-chamber social interaction test, and this protective effect might be attributed to the activation of the ERK/CREB/BDNF signaling pathway.

Conclusion: Therefore, AGM can effectively reduce the likelihood of offspring developing autism to a certain extent when exposed to VPA during pregnancy, serving as a potential therapeutic drug.

This builds on an earlier paper that first identified the benefit.

 

Agmatine rescues autistic behaviors in the valproic acid-induced animal model of autism

  

Highlights

•                  Single treatment of agmatine rescues social impairment in the VPA-induced animal model of autism.

•                  Effect of agmatine in social improvement in the VPA model is induced from agmatine itself, not its metabolite.

•                  Agmatine rescues repetitive and hyperactive behavior, and seizure susceptibility in the VPA model.

•                  Overly activated ERK1/2 in the brain of the VPA model is relieved by agmatine.

 

Apigenin

50mg of Apigenin

1g of dried parsley
15-20g of dried chamomile flowers

 

I have previously written about Apigenin, which is an OTC supplement. There has been another paper recently published about it. There is a logical connection with the maternal choline therapy from above.

 

What does Apigenin have in common with Choline?  α7-nAChRs

Choline is interesting because it acts as both a precursor for acetylcholine synthesis and it is a neuromodulator itself.

Choline is activates α7-nAChRs, alpha-7 nicotinic acetylcholine receptors.

These receptors are extremely important in learning and sensory processing.  They also play a key role in inflammation and signaling via the vagus nerve.

Apigenin is a flavonoid found in many plants, fruits, and vegetables. It has been shown to have a number of health benefits, including anti-inflammatory and antioxidant effects. Apigenin has also been shown to interact with α7-nAChRs.

Studies have shown that apigenin can:

Enhance α7-nAChR function: Apigenin has been shown to increase the activity of α7-nAChRs. This may be due to its ability to bind to a specific site on the receptor.

Protect α7-nAChRs from damage: Apigenin may also help to protect α7-nAChRs from damage caused by oxidative stress.

 

Apigenin Alleviates Autistic-like Stereotyped Repetitive Behaviors and Mitigates Brain Oxidative Stress in Mice

Studying the involvement of nicotinic acetylcholine receptors (nAChRs), specifically α7-nAChRs, in neuropsychiatric brain disorders such as autism spectrum disorder (ASD) has gained a growing interest. The flavonoid apigenin (APG) has been confirmed in its pharmacological action as a positive allosteric modulator of α7-nAChRs. However, there is no research describing the pharmacological potential of APG in ASD. The aim of this study was to evaluate the effects of the subchronic systemic treatment of APG (10–30 mg/kg) on ASD-like repetitive and compulsive-like behaviors and oxidative stress status in the hippocampus and cerebellum in BTBR mice, utilizing the reference drug aripiprazole (ARP, 1 mg/kg, i.p.). BTBR mice pretreated with APG (20 mg/kg) or ARP (1 mg/g, i.p.) displayed significant improvements in the marble-burying test (MBT), cotton-shredding test (CST), and self-grooming test (SGT) (all p < 0.05). However, a lower dose of APG (10 mg/kg, i.p.) failed to modulate behaviors in the MBT or SGT, but significantly attenuated the increased shredding behaviors in the CST of tested mice. Moreover, APG (10–30 mg/kg, i.p.) and ARP (1 mg/kg) moderated the disturbed levels of oxidative stress by mitigating the levels of catalase (CAT) and superoxide dismutase (SOD) in the hippocampus and cerebellum of treated BTBR mice. In patch clamp studies in hippocampal slices, the potency of choline (a selective agonist of α7-nAChRs) in activating fast inward currents was significantly potentiated following incubation with APG. Moreover, APG markedly potentiated the choline-induced enhancement of spontaneous inhibitory postsynaptic currents. The observed results propose the potential therapeutic use of APG in the management of ASD. However, further preclinical investigations in additional models and different rodent species are still needed to confirm the potential relevance of the therapeutic use of APG in ASD.

  

Altered acidity (pH) levels inside the brain

I found it intriguing that a large study has examined the altered acidity (pH) levels inside the brain of those with neurological disorders.

For all the disorders other than autism there was a clear pattern of low pH, which means increased acidity.

For autism certain autism models exhibited decreased pH and increased lactate levels, but others showed the opposite pattern, reflecting subpopulations within autism.

Altered brain energy metabolism is an acknowledged feature of autism, so we should not be surprised to find altered levels of acidity.

The easy reading version:

 

Brain Acidity Linked With Multiple Neurological Disorders

 

The study itself:

Large-scale animal model study uncovers altered brain pH and lactate levels as a transdiagnostic endophenotype of neuropsychiatric disorders involving cognitive impairment

Increased levels of lactate, an end-product of glycolysis, have been proposed as a potential surrogate marker for metabolic changes during neuronal excitation. These changes in lactate levels can result in decreased brain pH, which has been implicated in patients with various neuropsychiatric disorders. We previously demonstrated that such alterations are commonly observed in five mouse models of schizophrenia, bipolar disorder, and autism, suggesting a shared endophenotype among these disorders rather than mere artifacts due to medications or agonal state. However, there is still limited research on this phenomenon in animal models, leaving its generality across other disease animal models uncertain. Moreover, the association between changes in brain lactate levels and specific behavioral abnormalities remains unclear. To address these gaps, the International Brain pH Project Consortium investigated brain pH and lactate levels in 109 strains/conditions of 2,294 animals with genetic and other experimental manipulations relevant to neuropsychiatric disorders. Systematic analysis revealed that decreased brain pH and increased lactate levels were common features observed in multiple models of depression, epilepsy, Alzheimer’s disease, and some additional schizophrenia models. While certain autism models also exhibited decreased pH and increased lactate levels, others showed the opposite pattern, potentially reflecting subpopulations within the autism spectrum. Furthermore, utilizing large-scale behavioral test battery, a multivariate cross-validated prediction analysis demonstrated that poor working memory performance was predominantly associated with increased brain lactate levels. Importantly, this association was confirmed in an independent cohort of animal models. Collectively, these findings suggest that altered brain pH and lactate levels, which could be attributed to dysregulated excitation/inhibition balance, may serve as transdiagnostic endophenotypes of debilitating neuropsychiatric disorders characterized by cognitive impairment, irrespective of their beneficial or detrimental nature.

In conclusion, the present study demonstrated that altered brain pH and lactate levels are commonly observed in animal models of SZ, BD, ID, ASD, AD, and other neuropsychiatric disorders. These findings provide further evidence supporting the hypothesis that altered brain pH and lactate levels are not mere artifacts, such as those resulting from medication confounding, but are rather involved in the underlying pathophysiology of some patients with neuropsychiatric disorders. Altered brain energy metabolism or neural hyper- or hypoactivity leading to abnormal lactate levels and pH may serve as a potential therapeutic targets for neuropsychiatric disorders

 

Why would the brain be acidic (reduced pH)?

To function optimally mitochondria need adequate oxygen and glucose. When performance is impaired, for example due to the lack of Complex 1, mitochondria switch from OXPHOS (oxidative phosphorylation) to fermentation to produce energy (ATP). Lactic acid is the byproduct and this will lower pH.

 

Does brain pH matter?

It does matter and is linked to cognitive impairments, headaches, seizures etc.

Many enzymes in the brain rely on a specific pH range to function properly. Deviations from the ideal pH can hinder their activity, impacting various neurochemical processes essential for brain function.

Some ion channels are pH sensitive.

 

Chemical buffers in the brain aim to regulate pH in the brain

·       Carbonic Acid/Bicarbonate Buffer System: Similar to the blood, the brain utilizes this system to regulate pH.

·   Organic Phosphates: These molecules, like creatine phosphate, can act as buffers in the brain by binding or releasing hydrogen ions.

These buffering systems work together to maintain a tightly controlled pH range in both the blood (around 7.35-7.45) and the brain (slightly more acidic than blood, around 7.0-7.3). Even slight deviations from this ideal range can have significant consequences for cellular function.

  

Androgen Levels in Autism

Androgens are male hormones like testosterone, DHEA and DHT, but females have them too, just at lower levels.

Drugs that reduce the level of these hormones are called antiandrogens.

Finasteride reduces DHT and is used to treat hair loss in men as Propecia. This drug was trialed in women, but failed to show a benefit over the placebo.

The main use of Finasteride is for the treatment of benign prostatic hyperplasia (BPH) in older men.

Women sometimes take antiandrogens like Spironolactone to control acne.

Numerous studies have show elevated levels of males hormones in both males and females with autism.

A recent paper was published on this very subject: 

Androgen levels in autism spectrum disorders: A systematic review and meta-analysis

Background:

Accumulating evidence suggests that the autism spectrum disorder (ASD) population exhibits altered hormone levels, including androgens. However, studies on the regulation of androgens, such as testosterone and dehydroepiandrosterone (DHEA), in relation to sex differences in individuals with ASD are limited and inconsistent. We conducted the systematic review with meta-analysis to quantitatively summarise the blood, urine, or saliva androgen data between individuals with ASD and controls.

Methods:

A systematic search was conducted for eligible studies published before 16 January 2023 in six international and two Chinese databases. We computed summary statistics with a random-effects model. Publication bias was assessed using funnel plots and heterogeneity using I 2 statistics. Subgroup analysis was performed by age, sex, sample source, and measurement method to explain the heterogeneity.

Results:

17 case-control studies (individuals with ASD, 825; controls, 669) were assessed. Androgen levels were significantly higher in individuals with ASD than that in controls (SMD: 0.27, 95% CI: 0.06-0.48, P=0.01). Subgroup analysis showed significantly elevated levels of urinary total testosterone, urinary DHEA, and free testosterone in individuals with ASD. DHEA level was also significantly elevated in males with ASD. Androgen levels, especially free testosterone, may be elevated in individuals with ASD and DHEA levels may be specifically elevated in males.

 

By coincidence I was just sent the paper below, showing the benefit of Finasteride in one model of autism. 

Therapeutic effect of finasteride through its antiandrogenic and antioxidant role in a propionic acid-induced autism model: Demonstrated by behavioral tests, histological findings and MR spectroscopy

 

I do recall I think it was Tyler, long ago, writing a comment about the potential to use Finasteride in autism.

Some very expensive antiandrogens have been used in autism and this became rather controversial.

We saw in earlier posts that RORα/RORalpha/RORA is a key mechanism where the balance between male and female hormones controls some key autism gene.

 

The schematic illustrates a mechanism through which the observed reduction in RORA in autistic brain may lead to increased testosterone levels through downregulation of aromatase. Through AR, testosterone negatively modulates RORA, whereas estrogen upregulates RORA through ER.

 androgen receptor = AR             estrogen receptor = ER

Cerebellum and neurodevelopmental disorders: RORα is a unifying force

Errors of cerebellar development are increasingly acknowledged as risk factors for neuro-developmental disorders (NDDs), such as attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and schizophrenia. Evidence has been assembled from cerebellar abnormalities in autistic patients, as well as a range of genetic mutations identified in human patients that affect the cerebellar circuit, particularly Purkinje cells, and are associated with deficits of motor function, learning and social behavior; traits that are commonly associated with autism and schizophrenia. However, NDDs, such as ASD and schizophrenia, also include systemic abnormalities, e.g., chronic inflammation, abnormal circadian rhythms etc., which cannot be explained by lesions that only affect the cerebellum. Here we bring together phenotypic, circuit and structural evidence supporting the contribution of cerebellar dysfunction in NDDs and propose that the transcription factor Retinoid-related Orphan Receptor alpha (RORα) provides the missing link underlying both cerebellar and systemic abnormalities observed in NDDs. We present the role of RORα in cerebellar development and how the abnormalities that occur due to RORα deficiency could explain NDD symptoms. We then focus on how RORα is linked to NDDs, particularly ASD and schizophrenia, and how its diverse extra-cerebral actions can explain the systemic components of these diseases. Finally, we discuss how RORα-deficiency is likely a driving force for NDDs through its induction of cerebellar developmental defects, which in turn affect downstream targets, and its regulation of extracerebral systems, such as inflammation, circadian rhythms, and sexual dimorphism.

  

Figure 2. RORα regulates multiple genes and plays extensive roles in cerebellar development. (A) Key stages of PC development which are regulated by RORα. These are at all stages from embryonic development to adult maintenance. . (B) A schema showing the central role of RORα in multiple cellular processes, that are modified in NDDs. When RORα is reduced (central red circle), its regulation of gene transcription is altered. Here we include the known RORα target genes that are also involved in NDDs. The effects in red illustrate the induced abnormalities according to the direction of change: estrogen and PC development are reduced, circadian rhythms are perturbed, but inflammation and ROS are increased.

 

Sound sensitivity in autism and Nav1.2

At this point today’s post does get complicated.

Researchers have learnt that the sodium ion channel Nav1.2 (expressed by the SCN2A gene) can play a key role in hypersensitivity to sound in autism.

Lack of these ion channels in the cells that produce myelin produces “faulty auditory circuits”, with too much sound sensitivity.

An impairment in myelin structure can trigger cascading effects on neuronal excitability. Sound sensitivity is just one example.

There is a great deal of evidence that genes involved in myelination are miss-expressed in many models of autism. Imaging studies have shown variations in myelination.

 

Scn2a deletion disrupts oligodendroglia function: Implication for myelination, neural circuitry, and auditory hypersensitivity in ASD

Autism spectrum disorder (ASD) is characterized by a complex etiology, with genetic determinants significantly influencing its manifestation. Among these, the Scn2a gene emerges as a pivotal player, crucially involved in both glial and neuronal functionality. This study elucidates the underexplored roles of Scn2a in oligodendrocytes, and its subsequent impact on myelination and auditory neural processes. The results reveal a nuanced interplay between oligodendrocytes and axons, where Scn2a deletion causes alterations in the intricate process of myelination. This disruption, in turn, instigates changes in axonal properties and neuronal activities at the single cell level. Furthermore, oligodendrocyte-specific Scn2a deletion compromises the integrity of neural circuitry within auditory pathways, leading to auditory hypersensitivity—a common sensory abnormality observed in ASD. Through transcriptional profiling, we identified alterations in the expression of myelin-associated genes, highlighting the cellular consequences engendered by Scn2a deletion. In summary, the findings provide unprecedented insights into the pathway from Scn2a deletion in oligodendrocytes to sensory abnormalities in ASD, underscoring the integral role of Scn2a-mediated myelination in auditory responses. This research thereby provides novel insights into the intricate tapestry of genetic and cellular interactions inherent in ASD.

Therefore, our study underscores the region-specific relationship between myelin integrity and ion channel distribution in the developing brain. We emphasize that any disturbances in myelin structure can trigger cascading effects on neuronal excitability and synaptic function in the CNS, especially at nerve terminals in the auditory nervous system. 

How are Nav1.2  channels, encoded by Scn2a, involved in OL maturation and myelination? One possible explanation is that the activation of Nav1.2 may be pivotal for triggering Cav channel activation, leading to a Ca2+ flux within OLs, which is involved in OL proliferation, migration, and differentiation. Specifically, Ca2+ signaling facilitated by R-type Cav in myelin sheaths at paranodal regions, might influence the growth of myelin sheaths. To activate high-voltage activated calcium channels such as L- and R-Type efficiently, the activation of Nav1.2 channels should be required for depolarizing OL membrane to around -30 mV. Consequently, the synergic interplay between Nav1.2 and Cav channels could amplify calcium signaling in OLs, initiating the differentiation and maturation processes. 

Defects in myelination can create a spectrum of auditory dysfunctions, including hypersensitivity. Our results demonstrated how OL-Scn2a is involved in the relationship between myelin defects, neuronal excitability, and auditory pathology in ASD, potentially paving the way for targeted therapeutic interventions.

 

One subject that some people write to me repeatedly about is self-injurious behavior, so I took note of the paper below.  

Dopamine Transporter Binding Abnormalities Are Associated with Self-injurious Behavior in Autism Spectrum Disorder 

Utilizing single-photon emission computed tomography dopamine transporter scans (DaTscan) we examined whether imaging markers of the dopaminergic system are related to repetitive behaviors as assessed by the Repetitive Behavior Scale-Revised in ASD.

Background: 

Autism spectrum disorder (ASD) is characterized by impairments in social communication, and restricted repetitive behaviors. Self-injurious behaviors are often observed in individuals with ASD. Dopamine is critical in reward, memory, and motor control. Some propose the nigrostriatal motor pathway may be altered in ASD, and alterations in dopamine are reported in some rodent models based on specific ASD genes. Additionally, repetitive behaviors may to be related to reward systems. Therefore, we examined the dopaminergic system, using DaTscans, to explore its relationship with measures of repetitive behavior in a clinical ASD population.

Design/Methods: 

Twelve participants (aged 18–27) with ASD were recruited from the Thompson Center for Autism and Neurodevelopment and completed the Repetitive Behaviors Scale - Revised (RBS-R). Of the 12 participants, 10 underwent a 45-minute DaTscan. ANOVA was used to compare the dopamine imaging findings with the overall total RB scores on the RBS-R. while other domains of the RBS-R were also investigated in an exploratory manner.

Results: 

Five of the participants had regional deficits in dopamine transporter binding in the striatum on DaTscan. Individuals with deficits on the DaTscan had significantly higher Self-Injurious Endorsed Scores than those with normal scans.

Conclusions: 

Half of the DaTscans obtained were determined abnormal, and abnormal scans were associated with greater endorsing of self-injurious behavior. Larger samples are needed to confirm this, and determine the impact of laterality of abnormalities, but this preliminary work suggests a potential role the dopaminergic system in self-injurious RBs. Elucidation of this relationship may be important for future interventional outcomes, with potential impact on targeted treatment, as the only currently approved medications for ASD are atypical neuroleptics.

 

Dopamine transporter binding abnormalities refer to deviations from the normal levels of dopamine transporter (DAT) in the brain. DAT is a protein on the surface of cells that reabsorbs dopamine from the synapse, regulating its availability.

Imaging techniques like DAT scans (dopamine transporter scans) are used to assess DAT levels. These scans measure the binding of radiotracers to DAT, with lower binding indicating reduced DAT levels.

Dopamine transporter binding abnormalities have been linked to various neurological and psychiatric conditions, including:

•                 Parkinson's disease: Degeneration of dopamine-producing neurons in the substantia nigra, a hallmark of Parkinson's disease, leads to a significant decrease in dopamine levels and DAT binding in the striatum.

•                 Attention deficit hyperactivity disorder (ADHD): Some studies suggest that individuals with ADHD may have abnormal DAT function, though the nature of the abnormality (increased or decreased DAT) is debated.

•                 Autism spectrum disorder (ASD): Research suggests that a subgroup of individuals with ASD may have DAT abnormalities, potentially linked to repetitive behaviors and social difficulties.

•                 Addiction: Dopamine plays a central role in reward and motivation. Drugs like cocaine and methamphetamine can cause long-term changes in DAT function, potentially contributing to addiction.

DAT binding abnormalities may not always translate to functional impairments.

 

Treatment options for DAT binding abnormalities

Unfortunately, medications that directly target Dopamine Transporter (DAT) binding abnormalities do not exist.

In Parkinson's disease the goal is to increase dopamine levels in the brain. Medications like levodopa, a dopamine precursor, or dopamine agonists (drugs that mimic dopamine) are used.

  

Conclusion

It certainly is not easy to figure out how to treat autism and its troubling symptoms like self-injury. Our reader currently trying to make sure his second child does not have severe autism is wise to invest his time now.

Today we added agmatine and choline to our list of preventative strategies to consider.

As regards strategies to treat autism in children and adults, we see that the research very often is repeating what has already been published over the past two decades.

Ion channels do seem to be central to understanding and treating autism.