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Showing posts with label MCI. Show all posts
Showing posts with label MCI. Show all posts

Wednesday 25 April 2018

Arginine and its Derivatives in Cognitive Impairment


Source: Epiphany ASD Blog

Today’s post is very relevant to dementia, relevant to schizophrenia and diabetes and I believe some autism, including that of my son; agmatine is part of his Polypill therapy.
Arginine is highly versatile amino acid and you need the arginine metabolism to be working correctly, particularly in your brain.
Arginine is a widely available from diet and can be produced from citrulline and indirectly from glutamine; so you are unlikely to be deficient in arginine, except in your brain and particularly if you have Alzheimer’s.
In Alzheimer’s it has been shown that the microglia in effect destroy arginine in the brain and this may play a role in what initiates the disease.
Research has suggested that a deficiency in polyamines, another derivative of Arginine, is a feature of dementia.
A deficiency of arginine in the brain will likely cause a deficiency of polyamines.

Your body needs nitric oxide to maintain a healthy blood pressure and this requires arginine to follow the blue line in the above chart towards citrulline and be converted by eNOS.  In most older people this does not happen and oxidative stress appears to be a big part of the problem.

Agmatine – good 
Agmatine has been shown in research to have a benefit in Alzheimer’s.  

This could be due to increased eNOS improving blood flow, an increase in Polyamines, or by reducing insulin resistance in the brain. Recall those studies of intranasal insulin? We had "type 3 diabetes", which was a brain-specific blunting of insulin.

https://www.ncbi.nlm.nih.gov/pubmed/27810390 
"Agmatine administration rescued the reduction in insulin signalling, which in turn reduced the accumulation of Aβ and p-tau in the brain. Furthermore, agmatine treatment also reduced cognitive decline. Agmatine attenuated the occurrence of AD in T2DM mice via the activation of the blunted insulin signal"

Methylarginines – not good
Two by-products of arginine are bad for you in the way Agmatine is good for you.
Nitric Oxide is produced via iNOS, nNos and eNOS. In simple terms we want nitric oxide to be produced in the endothelium, the name for cells that line the interior surface of blood vessels and lymphatic vessels, To achieve this we needs lots of the enzyme eNOS and not much iNOS or nNOS, this is one of Agmatine’s jobs.
Two derivatives of arginine/proteins in the body with very long names are abbreviated to NMMA and ADMA. They both inhibit eNOS and so will restrict blood flow and this will appear as elevated blood pressure.   


Endogenous methylarginines, N(G),N(G)-dimethyl-L-arginine (asymmetric dimethylarginine, ADMA), N(G)-N('G)-dimethyl-L-arginine (symmetric dimethylarginine; SDMA), and N(G)-monomethyl-L-arginine (monomethyl arginine; NMMA) are supposed to be produced in human body through the methylation of protein arginine residues by protein arginine methyltransferases (PRMT) and released during proteolysis of the methylated proteins. Micromolar concentration of ADMA and NMMA can compete with arginine for nitric oxide synthase (NOS) reducing nitric oxide (NO) formation, whereas SDMA does not. Indeed, increased ADMA and SDMA plasma levels or a decreased arginine/ADMA ratio is related with risk factors for chronic kidney disease and cardiovascular disease. To the best of our knowledge the exogenous presence of methylarginines, like that in fruits and vegetables, has never been described so far. Here, we report the finding that methylarginines are ubiquitous in vegetables which represent an important part of human daily diet. Some of these vegetables contain discrete amounts of ADMA, SDMA, and NMMA. Specifically, among the vegetables examined, soybean, rye, sweet pepper, broad bean, and potato contain the highest ADMA and NMMA mean levels. Our results establish that the three methylarginines, in addition to being produced endogenously, can also be taken daily through the diet in conspicuous amounts. We propose that the contribution of the methylarginines contained in the vegetables of daily diet should be taken into account when the association between vegetable assumption and their levels is evaluated in clinical studies. Furthermore, a comprehensive understanding on the role of the digestive breakdown process and intestinal absorption grade of the methylarginines contained in vegetables is now needed. 

ADMA
Asymmetric dimethylarginine (ADMA) is a naturally occurring chemical found in blood plasma. It is closely related to L-arginine. ADMA interferes with L-arginine in the production of nitric oxide (NO), a key chemical involved in normal endothelial function and, by extension, cardiovascular health. ADMA inhibits eNOS, which in simple terms is the good NOS, the other two being iNOS and nNOS.
ADMA is considered a marker for vascular disease

NMMA (NG-monomethyl-l-arginine, or just called Targinine) 
The following study is very interesting for your older relatives. As we already know oxidative stress is a feature of aging. Many people have high blood pressure in old age. Nitric Oxide (NO) is needed keep blood vessels wide open. In old age (>60) oxidative stress reduces NO availability to nothing. 
Since oxidative stress is reversible (in this study vitamin C was used) you wonder why more older people, particularly with high blood pressure, do not take entioxidants. 


A novel finding of the present study is that in normotensive subjects, the reduction in endothelial function associated with aging seems to be mediated by a progressive reduction of NO availability, inasmuch as the inhibiting effect of L-NMMA on acetylcholine-induced vasodilation was progressively impaired by advancing age. It is worth noting that after the age of 60 years, the inhibiting effect of L-NMMA on response to acetylcholine was very weak, suggesting that in aged individuals NO availability is almost totally compromised. To assess the possible role exerted by oxidative stress, we tested the antioxidant vitamin C.19 Up to the age of 60 years, despite the evident decline in endothelium-dependent vasodilation, vitamin C did not modify the response to acetylcholine. In contrast, in the oldest individuals (age >60 years) characterized by a profound alteration in NO availability, vitamin C not only enhanced the response to the endothelial agonist but also restored the inhibiting effect of L-NMMA on vasodilation to acetylcholine. Thus, in the present study, the use of L-NMMA and vitamin C, never tested before in investigating the mechanisms responsible for the previously demonstrated age-related endothelial dysfunction in humans,17 seems to indicate that the progressive impairment in endothelium-dependent vasodilation is caused by a progressive alteration of the l-arginine-NO pathway. Only in old age (after ≈60 years) does the production of oxidative stress appear, leading to the complete compromise of NO availability.  

Arginase
Arginase is an enzyme that acts as the catalyst for the reaction.
 arginine + H2Oornithine + urea 

People with schizophrenia and also people with diabetes tend to have high levels of Arginase. This will affect how arginine is metabolized. If arginase is increased there is less arginine that can go towards creatine, citrulline or agmatine. 
Going towards citrulline involves the production of nitric oxide NO. Now in schizophrenia we see a reduction in the good type of NO, that produced in the endothelium, the cells that line the interior surface of blood vessels and lymphatic vessels. As a result, we vascular dysfunction in schizophrenia.
Agmatine is also elevated in schizophrenia, which may be one of those feedback loops since agmatine will inhibit iNOS, nNOS while increasing eNOS
So where is there a reduction in Arginine in schizophrenia?
Well it looks like it is creatine which takes the hit.


“Patients with schizophrenia had a statistically significant reduction in Cr levels as compared with controls; bipolar disorder patients showed no difference in Cr as compared with controls”

In people with elevated arginase a useful strategy might be to use an arginase inhibitor.


The next paper highlights the arginase inhibitor I favour, which is L-norvaline. The paper is from Kursk university. Kursk gave its name to the nuclear-powered submarine that was lost in the Barents Sea in 2000 and triggered a new international cooperation to rescue stricken submarines. The Battle of Kursk was the largest tank battle of all time and the final major offensive by the Germans against the Russians in World War 2, where Hitler wanted to cut off a large bulge in the front line and trap a lot of Russians. Thanks to some clever English mathematicians, encrypted German communications were readable and the Russians repositioned their forces in advance, allowing them to counter attack. The Allies then invaded Sicily and that was the end for the Germans in Russia. 

The present research shows expressed endothelium-protective property of arginase inhibitor, L-norvaline, characterized by decrease of coefficient of endothelial dysfunction and the approached its application to a group of intact animals. In other words, L-norvaline prevents the development of systemic endothelial dysfunctions in L-NAME- and methionine-induced NO deficiency.

Age-induced memory impairment (AMI)

Now we move to Polyamines that are on the bottom left my graphic at the start of this post. Spermidine and Spermine are very beneficial derivatives of arginine that most older people will be lacking. Autophagy is the cellular garbage disposal service that is dysfunction in many neurological disorders. We generally want more autophagy.

The aging process drives the progressive deterioration of an organism and is thus subject to a complex interplay of regulatory and executing mechanisms. Our understanding of this process eventually aims at the delay and/or prevention of age-related pathologies, among them the age-dependent decrease in cognitive performance (e.g., learning and memory). Using the fruit fly Drosophila melanogaster, which combines a generally high mechanistic conservation with an efficient experimental access regarding aging and memory studies, we have recently unveiled a protective function of polyamines (including spermidine) against age-induced memory impairment (AMI). The flies’ age-dependent decline of aversive olfactory memory, an established model for AMI, can be rescued by both pharmacological treatment with spermidine and genetic modulation that increases endogenous polyamine levels. Notably, we find that this effect strictly depends on autophagy, which is remarkable in light of the fact that autophagy is considered a key regulator of aging in other contexts. Given that polyamines in general and spermidine in particular are endogenous metabolites, our findings place them as candidate target substances for AMI treatment.  


Aging is the most important risk factor for cardiovascular disease (CVD). Slowing or reversing the physiological impact of heart aging may reduce morbidity and mortality associated with age-related CVD. The polyamines, spermine (SP) and spermidine (SPD) are essential for cell growth, differentiation and apoptosis, and levels of both decline with age. To explore the effects of these polyamines on heart aging, we administered SP or SPD intraperitoneally to 22- to 24-month-old rats for 6 weeks. Both treatments reversed and inhibited age-related myocardial morphology alterations, myocardial fibrosis, and cell apoptosis. Using combined proteomics and metabolomics analyses, we identified proteins and metabolites up- or downregulated by SP and SPD in aging rat hearts. SP upregulated 51 proteins and 28 metabolites while downregulating 80 proteins and 29 metabolites. SPD upregulated 44 proteins and 24 metabolites and downregulated 84 proteins and 176 metabolites. These molecules were mainly associated with immune responses, blood coagulation, lipid metabolism, and glutathione metabolism pathways. Our study provides novel molecular information on the cardioprotective effects of polyamines in the aging heart, and supports the notion that SP and SPD are potential clinical therapeutics targeting heart disease                                                               


Figure 1. summarizes the suggestion that spermidine-triggered restoration of autophagy protects synapses from age-induced changes, and thus delays the normally occurring decline of memory formation. Given that spermidine is a physiologic, easy administrable substance, future research may consider its supplementation to counter age-dependent dementia.
Spermidine operates directly at presynaptic active zone scaffolds (composed of Brp/bruchpilot protein) to allow for an autophagy-dependent homeostatic regulation of these specializations. In effect, spermidine protects learning efficacy from aging-induced decline.                                      


 Having your longevity and eating too
Although caloric restriction has clear benefits for maximizing health span and life span, it is sufficiently unpleasant that few humans stick to it. Madeo et al. review evidence that increased intake of the polyamine spermidine appears to reproduce many of the healthful effects of caloric restriction, and they explain its cellular actions, which include enhancement of autophagy and protein deacetylation. Spermidine is found in foods such as wheat germ, soybeans, nuts, and some fruits and vegetables and produced by the microbiota. Increased uptake of spermidine has protective effects against cancer, metabolic disease, heart disease, and neurodegeneration. 

Although spermidine induces autophagy and autophagy inhibition curtails many of the health-promoting effects of spermidine, additional mechanisms have been proposed to explain the beneficial effects of spermidine on aging. These potentially autophagy-independent mechanisms include direct antioxidant and metabolic effects on arginine bioavailability and nitric oxide (NO) production. However, it has not been formally determined whether these routes act in a completely autophagy-independent manner or are interrelated with autophagy (in an additive or synergistic way) (see the figure), and it will be important to define actionable molecular targets that explain the beneficial effects of spermidine in diverse pathophysiological settings. In this sense, it will also be of interest to explore synergisms of spermidine with other CRMs that initially act through different mechanisms.






It is a surprise that those long-lived Japanese eat Natto? Also, it is a good source of vitamin K2 and importantly it is an estrogen and so an ERβ agonist.


Not all probiotics are helpful to produce polyamines and one well known probiotic, VSL#3, has been shown to reduce their level. Choose your bacteria very carefully. 
Here the probiotic strain Bifidobacterium animalis subsp. lactis LKM512 is used to increase polyamine production



Alzheimer’s and Arginine
In a fairly recent study it was suggested that the immune system in the brain is being suppressed and the microglia are slightly mutated along with the over-expression of arginase. Arginase is the enzyme that coverts arginine to ornithine plus urea.

So, in Alzheimer’s there will be a lack of arginine available for its other purposes. 


So, we would expect a lack of creatine, agmatine and citrulline. Along the way we should see less Nitric Oxide.
Based on my graphic above, it would seem that L-Norvaline should improve the outcome in Alzheimer’s mice.
We already know that Agmatine improves Alzheimer’s mice, as we now should expect.
So, my cocktail for an aging mouse would be: - 

·        L-Norvaline (used by body builders)

·        Agmatine (used by body builders)

·        Creatine (used by body builders)

·        Natto/wheatgerm/ LKM512 probiotic

·        Vitamin C or NAC

·        Citrulline (used by body builders)

·        Betanin (an approved food colour additive, see below)

Served with cheese, naturally.

A New Potential Cause for Alzheimer’s: Arginine DeprivatiON

Alzheimer’s study suggests immune cells chew up an important amino acid 
Increasingly, evidence supports the idea that the immune system, which protects our bodies from foreign invaders, plays a part in Alzheimer’s disease. But the exact role of immunity in the disease is still a mystery. A new Duke University study in mice suggests that in Alzheimer’s disease, certain immune cells that normally protect the brain begin to abnormally consume an important nutrient: arginine. Blocking this process with a small-molecule drug prevented the characteristic brain plaques and memory loss in a mouse model of the disease. Published April 15 in the Journal of Neuroscience, the new research not only points to a new potential cause of Alzheimer’s but also may eventually lead to a new treatment strategy. “If indeed arginine consumption is so important to the disease process, maybe we could block it and reverse the disease,” said senior author Carol Colton, professor of neurology at the Duke University School of Medicine, and a member of the Duke Institute for Brain Sciences. The brains of people with Alzheimer’s disease show two hallmarks -- ‘plaques’ and ‘tangles’ -- that researchers have puzzled over for some time. Plaques are the build-up of sticky proteins called beta amyloid, and tangles are twisted strands of a protein called tau. In the study, the scientists used a type of mouse, called CVN-AD, that they had created several years ago by swapping out a handful of important genes to make the animal’s immune system more similar to a human’s. Compared with other mice used in Alzheimer’s research, the CVN-AD mouse has it all: plaques and tangles, behaviour changes, and neuron loss. In addition, the gradual onset of these symptoms in the CVN-AD mouse gave researchers a chance to study its brain over time and to focus on how the disease begins, said the study’s first author Matthew Kan, an MD/PhD student in Colton’s lab. Looking for immune abnormalities throughout the lifespan of the mice, the group found that most immune system components stayed the same in number, but a type of brain-resident immune cells called microglia that are known first responders to infection begin to divide and change early in the disease. The microglia express a molecule, CD11c, on their surface. Isolating these cells and analyzing their patterns of gene activity, the scientists found heightened expression of genes associated with suppression of the immune system. They also found dampened expression of genes that work to ramp up the immune system. “It’s surprising, because [suppression of the immune system is] not what the field has been thinking is happening in AD,” Kan said. Instead, scientists have previously assumed that the brain releases molecules involved in ramping up the immune system, that supposedly damage the brain. The group did find CD11c microglia and arginase, an enzyme that breaks down arginine, are highly expressed in regions of the brain involved in memory, in the same regions where neurons had died. Blocking arginase using the small drug difluoromethylornithine (DFMO) before the start of symptoms in the mice, the scientists saw fewer CD11c microglia and plaques develop in their brains. These mice performed better on memory tests. “All of this suggests to us that if you can block this local process of amino acid deprivation, then you can protect -- the mouse, at least -- from Alzheimer’s disease,” Kan said. DFMO is being investigated in human clinical trials to treat some types of cancer, but it hasn’t been tested as a potential therapy for Alzheimer’s. In the new study, Colton’s group administered it before the onset of symptoms; now they are investigating whether DFMO can treat features of Alzheimer’s after they appear. Does the study suggest that people should eat more arginine or take dietary supplements? The answer is ‘no,’ Colton said, partly because a dense mesh of cells and blood vessels called the blood-brain barrier determines how much arginine will enter the brain. Eating more arginine may not help more get into the sites of the brain that need it. Besides, if the scientists’ theory is correct, then the enzyme arginase, unless it’s blocked, would still break down the arginine. “We see this study opening the doors to thinking about Alzheimer’s in a completely different way, to break the stalemate of ideas in AD," Colton said. "The field has been driven by amyloid for the past 15, 20 years and we have to look at other things because we still do not understand the mechanism of disease or how to develop effective therapeutics

The full study: -

The pathogenesis of Alzheimer's disease (AD) is a critical unsolved question; and although recent studies have demonstrated a strong association between altered brain immune responses and disease progression, the mechanistic cause of neuronal dysfunction and death is unknown. We have previously described the unique CVN-AD mouse model of AD, in which immune-mediated nitric oxide is lowered to mimic human levels, resulting in a mouse model that demonstrates the cardinal features of AD, including amyloid deposition, hyperphosphorylated and aggregated tau, behavioral changes, and age-dependent hippocampal neuronal loss. Using this mouse model, we studied longitudinal changes in brain immunity in relation to neuronal loss and, contrary to the predominant view that AD pathology is driven by proinflammatory factors, we find that the pathology in CVN-AD mice is driven by local immune suppression. Areas of hippocampal neuronal death are associated with the presence of immunosuppressive CD11c(+) microglia and extracellular arginase, resulting in arginine catabolism and reduced levels of total brain arginine. Pharmacologic disruption of the arginine utilization pathway by an inhibitor of arginase and ornithine decarboxylase protected the mice from AD-like pathology and significantly decreased CD11c expression. Our findings strongly implicate local immune-mediated amino acid catabolism as a novel and potentially critical mechanism mediating the age-dependent and regional loss of neurons in humans with AD.

So Arginine for Alzheimer’s? Not so simple
Eating more arginine is not an effective way to increase the level of arginine in your brain and also the high level of arginase might just soak it all up anyway.
Other science does suggest that there are other ways to increase the amount of arginine in your brain, such as L-citrulline.  We have already seen that we can inhibit arginase with L-norvaline among other things.

Betanin for Alzheimer’s
Since we are on Alzheimer’s, we might as well include another clever idea.
Our reader Tyler highlighted another interesting Alzheimer’s study, which suggests preventing/treating Alzheimer’s with Betanin, the pigment in beet root.
This might sound mad, but is deadly serious. The research showed that Betanin inhibits the formation of the trademark beta-amyloid plaques that define Alzheimer’s. No plaques, no Alzheimer’s.


Beetroot has already been featured in this blog; it has numerous health benefits.

To lower blood pressure and increase exercise endurance it is the nitrates that are helpful, but beetroot has numerous other effects; it even increases insulin sensitivity, so is a good choice for diabetics and pre-diabetics.








Betanin without the beetroot?
Betanin has such a strong colour it is used commercially as a food colourant, it appears as E162 on the label. In Europe it is called Beetroot red E162 and is inexpensive.
Personally, I take my betanin with the rest of the beetroot. 

Vascular Dementia - before I forget

Vascular dementia is the easiest type of cognitive impairment to understand. Reduced blood flow to the brain, most likely due to reasons including a loss of endothelial nitric oxide, effectively starves the brain. We saw how cocoa flavanols improve blood flow and hence mild cognitive impairment, this is via an NO-dependent mechanism that nobody fully understands. In autism things get more complicated and we saw in earlier posts that we seem to have unstable blood flow rather than just reduced blood flow. Nonetheless, improving cerebral blood flow may well be useful for some people with autism; so more eNOS and not too much arginase, cocoa flavanols may well be beneficial. Antioxidants are hopefully already being taken.


Conclusion
I was surprised just how much in the post can be implemented today with no prescription medication.
It is no surprise that certain diets (Mediterranean/Okinawan) promote not only longevity but also an extended healthy life expectancy.
I think there are some tips here for fine tuning out of balance brains found in autism, schizophrenia and bipolar.
I hope someone trials my cocktail on an Alzheimer’s mouse and a regular older mouse. 

·        L-Norvaline and Citrulline

·        Agmatine

·        Creatine

·        Natto/wheatgerm/ LKM512 probiotic

·        Vitamin C or NAC

·        Betanin


I suspect this cocktail would be more effective than Donepezil or Memantine, neither of which address the underlying cause of Alzheimer's disease. In reality some of the above might not even be needed (e.g. creatine and citrulline).

Agmatine as an alternative for some people who respond to intranasal insulin is an interesting idea. Research seems to have stalled because the preservative in the insulin causes irritation inside the nose.

Note: Creatine deficiency is a known cause of MR/ID/Autism and some types are treatable  https://creatineinfo.org/. It is detectable by Magnetic Resonance Spectroscopy or by measuring creatine levels in plasma and urine. Babies born with creatine deficiency may exhibit hypotonia (floppy baby syndrome) due to weak muscles. 





Friday 17 November 2017

Beetroot - Cold Hands, Leukoaraiosis, Psychosis and Anxiety in Schizophrenia





Karimnagar, India, where Schizophrenic Rats respond well to Beetroot Juice

If you are not old enough to be interested in dementia, skip through those parts of this post and read about schizophrenic mice and beetroot juice.
There have been earlier posts regarding using nitric oxide (NO) to improve circulation and derive a cognitive benefit.
Many sportsmen have followed up on the research studies that show exercise endurance is improved after taking beet root juice. Since it is not a banned substance they are free to benefit from it.
We know that beet root does not only reduces blood pressure but it actually can increases perfusion, or blood flow, to the brain. Reduced blood flow to the brain is a feature of some dementia. Studies have used MRI to show that circulation is increased. A follow up study has recently been published which shows that beet root juice combined with exercise produced MRI results that resemble those of much younger adults.
In a previous post we saw that cocoa flavanols improved memory in older people and in effect brought them back to where they used to be 20 years previously. With cocoa the mechanism is not fully understood by is believed to “activate the nitric oxide system” in the brain. Cocoa does not produce nitric oxide in the way beet root does. Foods like beetroot and spinach contain large amounts of nitrates and they cause a measurable increase in circulating nitrites in the blood. The nitrites can later on become nitric oxide.
There is a lot of research into cocoa flavanols, mainly in relation to its benefit for those heart disease and more recently dementia. It also has benefits for anyone with diabetes, because it increases insulin sensitivity, as some readers of this blog have confirmed.
Cocoa flavanols appear to indirectly increase eNOS which then leads to more Nitric Oxide (NO). In addition there are antioxidant effects. eNOS reacts with L-arginine to produce NO.
But there is another way to make Nitic Oxide (NO), via nitrite that is circulating in your blood.  To increase nitrite you just eat nitrates, green leafy vegetables and beetroot.
It appears that eNOS does affect nitrite levels, so perhaps more eNOS means more NO is produced and then nitrite stays as nitrite and so the level of nitrite increases. Everything is inter-related.




Interestingly, statin drugs increase circulating nitrite levels just like beetroot.
NO bioavailability is determined by the balance between NO biosynthesis and its degradation by reactions with hemoglobin and reactive oxygen species (ROS).



So in people with oxidative stress there will be less NO. 

Nitric oxide (NO) is a potent signaling molecule that influences an array of physiological responses. It was traditionally assumed that NO was derived exclusively via the nitric oxide synthase (NOS) family of enzymes. This complex reaction requires a five electron oxidation of L-arginine and is contingent on the presence of numerous essential substrates (including O2) and co-factors. Recently an additional, O2-independent, NO generating pathway has been identified, where nitrite (NO2 ) can undergo a simple one electron reduction to yield NO. NO2 is produced endogenously from the oxidation of NO and also from the reduction of dietary nitrate (NO3 ) by facultative bacteria residing on the tongue. Recent data show that dietary NO3 supplementation, which increases the circulating plasma [NO2 ], reduces the O2 cost of submaximal exercise in healthy humans. This finding is striking given that efficiency during moderate-intensity exercise has been considered to be immutable. Therefore, dietary NO3 supplementation may represent a practical and cost-effective method to improve exercise efficiency and exercise tolerance in humans. Given that a NO3 -rich diet may have numerous cardiovascular and other health benefits, dietary NO3 intake may have important implications for human lifelong health and performance.
   
Cold hands
People with poor circulation tend to have cold hands and feet. From the comments in this blog it appears that many people with autism have cold hands/feet.
Do the many Nitric Oxide producing therapies used by sportsmen “warm up” cold hands?
Well we do actually now have some data on this subject. 


At least in the case of beetroot the answer is no.


L-arginine, L-citrulline, eNOS and NO    
It does appear that more eNOS can be beneficial. More eNOS means more NO as long as there is enough L-arginine. If you want to make more L-arginine, the most effective way is to eat L-citrulline, which is abundant in water melon.
It looks like some people lack arginine while others lack eNOS.  The males in clinical trials of citrulline and water melon, as a Viagra alternative, must lack L-arginine.
I think in autism the problem is lack of eNOS.
I thought L-citrulline might increase the positive effect of Agmatine that is very evident in Monty, aged 14 with ASD, but it has no additional effect.
Maybe some people do lack eNOS and l-arginine.
You do not need eNOS to make nitric oxide from the nitrites produced by beetroot juice.

Agmatine
We previously saw that the OTC supplement Agmatine increases eNOS, but it also actually affects BDNF.

Taken together, the findings of this study show that long-term agmatine administration increases the BDNF levels in both the hippocampus and amygdala, and also peripherally the NO synthesis and/or bioavailability, and corrects the age-related endothelial dysfunction, and hence may help in recovering vascular aging and vascular dementia.


Leukoaraiosis
Leukoaraiosis is a new word to this blog, it is very relevant to dementia, but it would likely only be relevant to autism if there has been hypoxia (lack of oxygen). Two readers of this blog do report hypoxia.
There is a lot of information in this blog about treating dementia and so for the sake of completeness I will elaborate further.
It appears that most people with Mild Cognitive Impairment (MCI) or dementia have lsome eukoaraiosis.
Leukoaraiosis also referred as ischemic demyelination or age-related white matter disease, is a radiological term given to white spots that appear on your MRI scan.

It is commonly observed in elderly people, and it is often a finding related to vascular dementia.  Histology from these lesions show atrophy of axons and decreased myelin. It is thought that localized hypoxia is what caused the damage.

On both CT and MRI, leukoaraiosis is characterized by bilateral patchy or confluent white matter changes.
So if your “autism” resulted from hypoxia, you might expect to see white spots on your MRI scan.
What is interesting is that leukoaraiosis may contribute to ongoing mild hypoxia.
It always seemed odd that people might benefit from HBOT (hyperbaric oxygen) years after they suffered acute hypoxia; but if the acute hypoxia left leukoaraiosis, perhaps this then reduces ongoing blood flow and thus leaves mild localized hypoxia, which does respond to treatment.
When blood flow is interrupted to part of the brain your doctor would call that a stroke.  A mini-stroke occurs when that blood flow is only temporarily interrupted.  These so-called transient ischemic attacks (TIA) are a warning sign of what may come shortly afterwards.
It appears in many people mini-strokes occur but remain unreported.
As a result of mini-strokes and/or leukoaraiosis perfusion in older people is not as good as in younger people and so cognition and memory suffer.
This can be partially addressed by making your blood more “slippery” using low dose aspirin, but the risk is that over the years blood vessels have narrowed and become brittle.  You then risk micro bleeds where the blood vessel cracks and the “slippery” blood can leak out.  This does happen in the brain
Cerebral microbleeds are not rare and are seen as another cause of cognitive impairment.





The conclusion for adults is that prevention is much better than cure. A diet rich in nitrates (spinach beetroot etc) and flavanols (cocoa etc) plenty of exercise and avoiding half a century of high cholesterol looks a wise choice. 

Emerging evidence suggests that silent strokes or lacunar infarctions, leukoaraiosis, and vascular diseases may be associated with cognitive impairment including dementia. We assessed the occurrence of these risk factors among various spectrum of cognitive dysfunction. A retrospective review of patients evaluated in Guam with the diagnosis of Memory Loss, Mild Cognitive Impairment (MCI) and Dementia from August 2006 to December 2014 was conducted. The history of stroke and co-morbid vascular diseases was identified. The neuro-imaging studies were reviewed to determine the presence of silent strokes and leukoaraiosis in patients without history of a clinical stroke. There were 585 patients included in the analysis. One hundred forty two patients having a diagnosis of memory loss, 95 have MCI and 348 have dementia. A history of stroke was present in 29% of patients with Memory Loss, 20% of patients with MCI and 30% of patients with dementia. Silent strokes without a history of clinical stroke were present in 10% of patients with memory loss and MCI, and 15% of patients with dementia. The presence of Leukoaraiosis was present in 50% of patients with memory loss, 56% of patients with MCI, and 60% of patients with dementia. Occurrences of vascular diseases were higher in patients with dementia than patients with Memory Loss and MCI. In conclusion, silent strokes, leukoaraiosis and vascular diseases are found to be more prevalent in patients with Dementia than those with Memory Loss and MCI.  

Oxygen deprived areas of the brain can change the way the brain functions in older adults. These areas of the brain were thought to be just a normal part of aging and could lead to other diseases such as Alzheimer's or stroke.
Leukoaraiosis is described as a condition where brain scans (CT or MRI) show bright white dots. These areas of the brain are deprived of oxygen and were considered to be a normal part of aging process.
"There has been a lot of controversy over these commonly identified abnormalities on MRI scans and their clinical impact. In the past leukoaraiosis has been considered a benign part of the aging process, like gray hair and wrinkles," said Kirk M. Welker, M.D., assistant professor of radiology in the College of Medicine at Mayo Clinic in Rochester, Minn., in a press release.
The condition is common in people who are above the age of 60. Recently, leukoaraiosis has been linked to diseases like Alzheimer's, hypertension and stroke.
"We know that aging is a risk factor for leukoaraiosis, and we suspect that high blood pressure may also play a role," Dr. Welker said.
Researchers from the Mayo Clinic obtained brain scans from 18 participants over the age of 60. The brain scans of these participants were matched against those obtained from a control group. Researchers found that these participants had lesions in the brain that were 25 millimeters long while some lesions in the brains of control group participants were about five millimeters long.
The participants were given tests based on words and visual patterns. All the participants were connected to brain scanners during the tests.
The participants of control group and study group completed the task with similar speed. However, researchers found that the brains of people who had moderate leukoaraiosis worked differently than people who had mild lesions.
They found that areas of brains that performed word-association tasks weren't activated during the test but areas that process visual patterns were highly activated.
"Different systems of the brain respond differently to disease. White matter damage affects connections within the brain's language network, which leads to an overall reduction in network activity," Dr. Welker said.
Welker said that diagnosing leukoaraiosis is important in people who are above 60, especially those who have to undergo brain surgery and those who are part of scientific research study.
Previous research shows that the probability of stroke increases with increase in leukoaraiosis spread.
"Our results add to a growing body of evidence that this is a disease we need to pay attention to Leukoaraiosis is not a benign manifestation of aging but an important pathologic condition that alters brain function," Welker said.  

Finally, now you know all about leukoaraiosis, back to beet root juice.


Background:
Exercise has positive neuroplastic effects on the aging brain. It has also been shown that ingestion of beet root juice (BRJ) increases blood flow to the brain and enhances exercise performance. Here, we examined whether there are synergistic effects of BRJ and exercise on neuroplasticity in the aging brain.
Methods:
Peak metabolic equivalent (MET) capacity and resting-state magnetic resonance imaging functional brain network organization are reported on 26 older (mean age = 65.4 years) participants randomly assigned to 6 weeks of exercise + BRJ or exercise + placebo.
Results:
Somatomotor community structure consistency was significantly enhanced in the exercise + BRJ group following the intervention (MBRJ = -2.27, SE = 0.145, MPlacebo = -2.89, SE = 0.156, p = .007). Differences in second-order connections between the somatomotor cortex and insular cortex were also significant; the exercise + BRJ group (M = 3.28, SE = 0.167) had a significantly lower number of connections than exercise + placebo (M = 3.91, SE = 0.18, p = .017) following the intervention. Evaluation of peak MET capacity revealed a trend for the exercise + BRJ group to have higher MET capacity following the intervention.
Conclusions:
Older adults who exercised and consumed BRJ demonstrated greater consistency within the motor community and fewer secondary connections with the insular cortex compared with those who exercised without BRJ. The exercise + BRJ group had brain networks that more closely resembled those of younger adults, showing the potential enhanced neuroplasticity conferred by combining exercise and BRJ consumption.  
BRJ is clearly an encouraging nutritional supplement that may improve functional health in older adults, and the proposed primary mechanism of benefit of BRJ is the rise in plasma nitrite caused by the high levels of dietary nitrate in BRJ (32). Consumed nitrate, once absorbed from the intestine, is taken up from the plasma by salivary glands and concentrated in saliva; nitrate is subsequently reduced to nitrite by oral bacteria and ultimately absorbed into the circulatory system (32,33). Nitrite appears to be reduced to NO during hypoxia. NO is an antioxidant and a potent vasodilator (34,35), is a critical relaxation factor synthesized in endothelial cells (36,37), and is key to vascular compliance. For this study, we hypothesized that reductions in brain blood flow associated with hypertension and aging associated leukoaraiosis result in low-grade hypoxia (38) and that these reductions might be offset by the NO-mediated vasodilation in hypoxic regions due to the increased amount of circulating nitrite from the BRJ ingestion. Indeed, results from our lab have shown that 24 hours of a high nitrate diet supplemented with a single dose of BRJ leads to increased regional CBF in older adults (39). Coupled with exercise (a hypoxia-inducing activity), we propose that the biological mechanism underlying the neural plasticity shown in Figure 1 resulted from increased NO bioavailability after drinking BRJ





Supplementation with nitrate (NO3)-rich beetroot juice has been shown to improve exercise performance and cardiovascular (CV) responses, due to an increased nitric oxide (NO) availability. However, it is unclear whether these benefits are greater in older adults who have an age-related decrease in NO and higher risk of disease. This systematic review examines 12 randomised, crossover, control trials, investigating food-based NO3 supplementation in older adults and its potential benefits on physiological and cognitive performances, and CV, cerebrovascular and metabolic health. Four studies found improvements in physiological performance (time to exhaustion) following dietary NO3 supplementation in older adults. Benefits on cognitive performance were unclear. Six studies reported improvements in CV health (blood pressure and blood flow), while six found no improvement. One study showed improvements in cerebrovascular health and two found no improvement in metabolic health. The current literature indicates positive effects of dietary NO3 supplementation in older adults on physiological performance, with some evidence indicating benefits on cardiovascular and cerebrovascular health. Effects on cognitive performance were mixed and studies on metabolic health indicated no benefit. However, there has been limited research conducted on the effects of dietary NO3 supplementation in older adults, thus, further study, utilising a randomised, double-blind, control trial design, is warranted.
  
Beet Root and Schizophrenia
Having read about cocoa and beet root a long time ago, I did try both on myself. I think beet root has effects that go well beyond lowering blood pressure.
There are of course no trials of beet root in autism, but there is one in the next closest thing, schizophrenia. Unfortunately it was in rats, but nonetheless the findings are interesting.
   
In recent years, there has been much focus on the apparent heterogeneity of schizophrenic symptoms. By contrast, this article proposes a unifying account emphasizing basic abnormalities of consciousness that underlie and also antecede a disparate assortment of signs and symptoms. Schizophrenia, is fundamentally a self-disorder or ipseity disturbance is  characterized by complementary distortions of the act of awareness, hyper reflexivity and diminished self-affection. Anxiety impacts people in ways that they are unaware. In the presence of anxiety, attention is highly directed towards threatening information. Recently, anxiety was found to impact task switching performance when threatening stimuli were present. In the current study, we examined the Anxiolytic and antipsychotic activity of Beet Root Juice (BRJ) in rats. This study reveals that the BRJ has showed decreased effects of turning behaviour, weaving behaviour, head bobbing and falling behaviour. It also showed decreased effect of loco motor activity and increase in catalepsy scoring. Thus it shows anti psychotic and anti anxiety effects.

Ketamine-Induced Stereotypic Behaviour in Mice
Animals were divided into five groups and each group consisted of four animals. The control animals received normal diet and treated with Ketamine (50 mg/kg) for 15 consecutive days. The animals of standard groups received Olanzapine (5 mg/kg) after 30 min Ketamine was given, (50 mg/kg) for 15 consecutive days. The animals of test groups received different concentrations of BRJ (2 , 4, 8% w/w) through a specially prepared diet and after 30 min Ketamine was given (50 mg/kg) for 15 consecutive days. Each rat was individually placed into plastic cages (37 × 24 × 30 cm3) divided into quadrants by lines on the floor and allowed to acclimatize for at least 30 min before the testing began. Behavioural tests were performed between 10 a.m. and 4 p.m. The stereotypic behaviour was assessed by counting the number of turning, weaving, head-bobbing and ataxia. Turning was measured by counting turn around every 15 min over 60 min. Weaving and head-bobbing were measured by counting its neck wave right and left, and go up and down every 15 min over 60 min. Ataxia was assessed by counting the number of falls of each rat on the floor of the cage every 15 min over 60 min period

Beet root juice was as effective as Olanzapine, an antipsychotic medication used to treat schizophrenia and bipolar disorder. (Ketamine is what creates the stereotypy)



Beet root juice was more effective than Haloperidol, a typical antipsychotic medication used in the treatment of schizophrenia, tics in Tourette syndrome and  mania in bipolar disorder


Beet root was as effective as Diazepam (aka Valium), is a medication of the benzodiazepine family that typically produces a calming effect 



I found the above paper very surprising. It certainly supports my feeling about the effects of beet root juice being beyond just lowering blood pressure. It definitely has a calming effect on me, so it is not just in rats.

Beetroot Juice for Autism?
Why not try just try it?
It does taste better when it is 25% apple juice and 75% beetroot.
You can also use freeze dried beetroot powder, which can be put in capsules.
It is not clear the amount of powder you need.
>150 ml a day of juice gives the exercise endurance effect and the calming (Diazepam) effect.  I would guess 2 or 3 fresh beet root would be equivalent.
Freeze dried beet root powder appears to remove 90% of the weight. So 3g of powder equals about 30g of beetroot.
Some people use a teaspoon of beetroot powder to control blood pressure. 
I expect there are studies on beetroot powder and blood pressure.
I concluded in Monty, aged 14 with ASD, that while Agmatine has a significant effect from the first day citrulline has no noticeable effect whatsoever (so no lack of L-arginine).  Having just read about the rats from Karimnagar, India in the above study I started offering Monty some of my beetroot juice. I have filled some large gelatin capsules with freeze dried beetroot, but it is not clear how much you would need.  Better to stick with the juice and see if it does anything.
Beet root is rich in betaine, which is also good for you.
I think Agmatine increases eNOS and also NO, by increasing dietary nitrate we make more nitrite which is available to make more NO as it gets depleted by oxidative stress (Reactive Oxygen Species). It looks like some people with autism have no shortage of L-arginine and so there is no effect from arginine or citrulline supplementation.
I think there is a rationale to consider Agmatine and Beetroot juice. We do have the surprising results from the schizophrenic rats, which do suggest there can be a benefit. 
I have to say that after a year of drinking 150ml of beetroot juice a day, I am a convert. You do get used to the taste. 
Beetroot, cinnamon and cocoa flavanols are quite potent potential non-drug therapies for dementia and not forgetting where you left your car keys.