UA-45667900-1
Showing posts with label Testosterone. Show all posts
Showing posts with label Testosterone. Show all posts

Saturday, 27 December 2025

There’s nothing boring about boron – why 3mg of boron should be in multivitamins and some could take 6-10mg

 


Contents of a common multivitamin for adults


I wrote this post a while back and, the more I think about it, the more I see boron as a potentially useful autism therapy. It is safe, OTC, very cheap and has several mechanisms that should be beneficial. Notably, it reduces inflammation (CRP can fall as much as 50% in 10 days) and it increases estrogen receptor beta signaling (relevant to the brain and bones); both these factors are very relevant in severe autism. It has no effect on estrogen receptor alpha, so avoids the side effects of phytoestrogens and estradiol. I started taking it myself.

Believe it or not, even with a strange subject like boron, there is an autism angle.

I originally stumbled upon boron while researching bone metabolism. I expected it to be relevant only for bones and joint pain. Instead, I was surprised by the sheer breadth of its biological effects: inflammation, hormones, detoxification, memory, immunity, even cancer risk.

Boron is one of those nutrients that no one thinks about because it has not yet been officially classified as essential for humans. That means:

·         No recommended daily intake

·         Almost no multivitamin includes it

·         Most people are taking in less than 1 mg/day through diet

And yet clinically meaningful benefits only begin at least 3 mg/day.

This is especially relevant to people with restricted diets. Many autistic individuals eat the infamous “beige diet” of pasta, bread, chips/crisps, and nuggets. Telling them that avocados contain boron or that leafy greens contain manganese goes nowhere.

Even Monty, now 22, who eats very well, does not reach 3 mg/day of boron from food. He would need to drink half a bottle of high-boron Pinot Noir a day to get close!  

This post has some of the science at the back as non-essential reading.

If you are male, make sure to read the part about male hormones. It looks like a potentially good way to avoid benign prostate enlargement as you age. Prostate size was reduced by about 35% in those with high boron in their drinking water. Not surprisingly, this potential therapy has not been seriously followed up.

If you are female take a note of the female hormone effects.

 

What Boron Actually Does

From the open-access paper Nothing Boring About Boron just click on it to read the full paper


Boron influences multiple systems simultaneously. Benefits documented at 3+ mg/day include:

1. Bone health

·  Essential for bone growth and mineralization

·  Improves calcium and magnesium use

·  Synergistic with vitamin D and estrogen

2. Collagen health (Joints, bone matrix, intervertebral discs, eyes etc)

Remarkably, studies show that adults with a high boron intake seem protected from getting osteoarthritis in later life. Boron is even therapeutic in people who already have this type of arthritis. 

·   Boron improves collagen cross-linking, making fibres stronger, more elastic, and more resistant to breakdown.

·   Enhances vitamin D and magnesium biochemistry, both required for hydroxylating proline/lysine — the two amino acids that give collagen structural strength.

·   Reduces collagen-degrading enzymes (MMP-2 and MMP-9), protecting connective tissue from inflammatory destruction.

·   Boosts bone collagen quality, improving bone strength independently of calcium intake.

·   Supports joint cartilage and reduces arthritis symptoms, likely via improved collagen structure and reduced inflammation.

·   May slow collagen degeneration in the vitreous, explaining why boron sometimes helps with eye floaters.

3. Hormone regulation

·  Increases free testosterone in men

·  Normalizes estrogen metabolism in women

·  Enhances vitamin D activation

·  Reduces SHBG (sex hormone–binding globulin)

4. Anti-inflammatory effects

·  Reduces CRP, TNF-α, IL-6

·  Lowers oxidative stress

·  Raises glutathione peroxidase, catalase, and SOD

5. Detoxification

·   Reduces toxicity of heavy metals

·    Mitigates pesticide-induced oxidative stress

·    Improves cell membrane stability

6. Brain health

·    Improves electrical activity in the brain

·    Enhances short-term memory

·    Supports NAD⁺ and SAM-e pathways

·    Has neuroprotective properties

7. Anti-cancer activity

·     Signals against prostate, breast, lung cancer

·     Reduces tumor growth in models

·     Enhances chemotherapy efficacy

·     Protects normal tissue from chemo damage

Across dozens of studies these effects do not appear at <3 mg/day.

Safety is extremely high, with an upper limit of 20 mg/day for adults.

Boron and Autism — Small Study, Big Signal

A 2024 study examined boron in a rat autism model induced by propionic acid (PPA). 

Effects of Boron on Learning and Behavioral Disorders in Rat Autism Model Induced by Intracerebroventricular Propionic Acid

This model replicates:

·   neuroinflammation

·   microglial activation

·   elevated cytokines

·   reduced Purkinje cells

·   learning/social behaviour deficits

·   increased BDNF (a maladaptive elevation)

What 4 mg/kg boron (boric acid) did:

  • improved learning and social interaction
  • significantly lowered TNF-α, IL-6, IL-1β
  • reduced microglial & astrocyte activation
  • restored Purkinje cell numbers
  • normalised BDNF
  • provided broad neuroprotection

This lines up with boron’s known biology:

  • anti-inflammatory
  • antioxidant
  • mitochondrial support
  • hormone modulation
  • detoxification
  • microglial regulation

This does not mean boron is a cure for autism, but it clearly has biological relevance.

Given the low cost, excellent safety, and widespread deficiency, 3+ mg/day makes sense for most people, especially those with restrictive diets or systemic inflammation.

Boron and Hormones — Very Interesting Male vs Female Effects

Boron’s effect on hormones is surprisingly strong and well documented. This is where things get very interesting because the effects differ between men and women.

In Men: Free Testosterone Booster

Studies show that 6 mg/day of boron for 1 week:

  • free testosterone by 25%
  • estradiol by 50%
  • SHBG (sex hormone-binding globulin)
  • inflammatory markers (CRP dropped by 60%)

Why does this matter?

Reduced SHBG means more biologically active testosterone. This is not like taking steroids; it is allowing your existing testosterone to circulate freely.

Results seen:

  • increased libido
  • improved mood
  • better energy
  • increased muscle response to training
  • reduced inflammation
  • possibly lower prostate cancer risk 

There was a Turkish observational study (from the 1990s, often cited in boron research summaries) looking at a village with very high natural boron levels in soil and drinking water.

Men in this village consumed boron intakes around 6–30 mg/day (far above typical Western intake of 1 mg/day).

Compared with men from nearby normal-boron areas, they had:

·         Significantly smaller prostate volumes

·         Lower PSA levels

·         Lower rates of prostate enlargement (BPH)

No increase in adverse effects was detected in these high-boron consumers.

Boron has several effects relevant to prostate size:

·         Lowers inflammation (↓ NF-κB, ↓ cytokines)

·         Improves androgen–estrogen balance

·         Mild increase in free testosterone

·         Mild decrease in estradiol

This combination tends to lead to smaller prostates and lower PSA, especially in older men.

Does This Apply to Supplement Use?

Probably, but not to the same magnitude unless the dosage is comparable.

BORON SUPPLEMENT EFFECTS:

3 mg/day → measurable anti-inflammatory and hormonal effects

6–10 mg/day → stronger hormonal shift

10–12 mg/day → studied in athletes for testosterone effects

Does this explain why boron helps older men?

Yes. Older men typically develop:

·         Low free testosterone

·         Higher estradiol

·         Chronic prostate inflammation

Boron improves those three issues at once.

 

In Women: Estrogen Metabolism & Menopause Support

Boron helps women balance estrogen in a very different way:

·         increases estrogen when estrogen is too low

·         reduces “bad” estrogen metabolites (16α-hydroxyestrone)

·         increases “good” metabolites (2-hydroxyestrone)

·         improves response to vitamin D

·         reduces menstrual pain

·         supports bone density after menopause

In post-menopausal women:

·         urine calcium loss drops dramatically

·         vitamin D activation improves

·         bone turnover markers improve

Women deficient in magnesium or vitamin D benefit especially.

Why the Sex Difference?

Boron seems to act primarily by:

·    lowering SHBG (men see a larger effect), Sex Hormone–Binding Globulin is a protein made in the liver that binds tightly to sex hormones, mainly Testosterone, Dihydrotestosterone (DHT) and Estradiol

·    shifting estrogen metabolites (women see a larger effect)

·    enhancing vitamin D activation (beneficial for all)

·    reducing inflammation (universally helpful)

This dual effect is rare—few minerals have male/female divergence.

Boron-Rich Foods and Typical Intake Levels

Food

Boron (mg per 100 g)

Notes

Avocado

2.1 mg

One of the richest natural sources

Raisins

2.5 mg

Dried fruit is consistently high

Prunes

1.9 mg

Very dense source

Almonds

2.8 mg

Nuts are excellent

Hazelnuts

2.7 mg

Similar to almonds

Peanuts

1.4 mg

Lower but common

Peanut butter

1.9 mg

Higher concentration

Beans (various)

0.5–1.5 mg

Good but variable

Chickpeas

0.7 mg

Decent source

Lentils

0.7 mg

Regular intake helps

Dates

1.1 mg

Very effective

Red wine

0.5–0.7 mg per glass

Grapes are boron-rich

Apples

0.3 mg

Everyday source

Pears

0.4 mg

Another fruit source

Vegetables (general)

0.1–0.6 mg

Depends on soil content

Typical Daily Intake From Diet

·         Developed countries average 0.8–1.4 mg/day

·         Mediterranean diet: 2–3 mg/day

·         Vegan diets: 3–6 mg/day (high fruit/nut consumption)

Nearly all Western omnivorous diets fall below the 3 mg/day threshold associated with documented benefits.

Conlusion

Boron is one of the few nutrients where:

·         the safety is high

·         the benefits are large

·         the deficiency is common

·         the cost is trivial

And because modern diets (and nearly all multivitamins) provide little to none, 3 mg/day is a simple, evidence-based upgrade for anyone—especially those with osteopenia, inflammation, hormonal imbalance, or restrictive diets such as those often seen in autism.

Higher doses like 10mg would seem appropriate for specific groups that are likely to benefit from the effects described in this post.

How much boron did they give the rats with autism?

One thing you very quickly learn when reading animal studies is that the dose used in rats is almost always huge. The same is true in the recent study looking at boron in a propionic-acid model of autism. On paper, the researchers used “2 mg/kg and 4 mg/kg of boric acid.” That sounds modest, rats are small.

In toxicology, a rat “mg/kg” is not the same as a human “mg/kg.” Rats have a much faster metabolism, and their surface-area-to-body-weight ratio is different. If you dose a human the same way you dose a rat, you will rapidly enter “please call poison control” territory.

To make sense of rodent studies, you have to convert the dose using the FDA’s body-surface-area formula. When you do that, the “4 mg/kg” rat dose becomes roughly the human equivalent of:

45 mg/day of boric acid

which equals 7–8 mg of elemental boron, a dose that’s above normal diet but within the range of commercially available supplements.

But, that is a conservative conversion. There are other conversion models that give an equivalent human dose much higher, in the 35-80 mg/day range.

In reality, nobody knows the human dose that would give the same benefits as found in the rat study. Those rats with autism were essentially on very high pharmacological boron, not the gentle nutritional 3 mg/day found in health-food circles.

No wonder the effects were dramatic:

·         inflammation markers (IL-6, IL-1β, TNF-α) crashed

·         microglia and astrocytes calmed down

·         Purkinje cell loss reversed

·         learning and social behaviours improved

All good news — just not at “one avocado per day” boron levels.This is the same situation as resveratrol, curcumin, sulforaphane, luteolin, quercetin, and a dozen other compounds: the rodent study shows us mechanism and potential, but not a directly usable human dose. Still, what is remarkable is that even at low human doses (3–10 mg/day), boron does show measurable changes in humans: reduced inflammation, altered SHBG, higher free testosterone, better vitamin D handling, and nicer bone and joint metabolism.

So the take-home message is that the autism rat study used a boron dose equivalent to well above what humans safely take as a supplement — but it confirms that boron is a potent anti-inflammatory and neuroprotective micronutrient, and that even low doses may be biologically meaningful.

Perfectly reasonable to include boron in a multivitamin. It would save people a lot of bother.

Not reasonable to copy rat dosing, unless you happen to be a rat!





Tuesday, 23 April 2024

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.