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Showing posts with label L-Citrulline. Show all posts
Showing posts with label L-Citrulline. Show all posts

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.







Friday, 13 October 2017

Nitric Oxide (NO), Arginase and Endothelial Dysfunction in Autism








Endothelial dysfunction is not something people associate with autism. It is something I have covered previously in this blog and if you search on Google my post is about all you will find.
Endothelial dysfunction is acknowledged to be very important in diabetes, which is characterized by ROS (reactive oxygen species), reduced NO (nitric oxide) , reduced eNOS (endothelial nitric oxide synthase) and too much Arginase. There is also Peroxynitrite (ONOO), an ion we have encountered before.
In autism we do already know from the research that VEGF (Vascular endothelial growth factor) is disturbed and there will be a post on that.
So when you put it all this together, it is odd that nobody has researched endothelial dysfunction and autism.  When I find something like this, my fallback is always schizophrenia. What about Endothelial Dysfunction and Schizophrenia? Sure enough, there is plenty of research on the subject, like this paper.


We tested the hypothesis that subjects with schizophrenia have impaired endothelial function.
Our findings suggest that a diagnosis of schizophrenia is associated with impaired microvascular function as indicated by lower values of VTI, irrespective of many other clinical characteristics. It might be an early indicator of cardiovascular risk in schizophrenia, and might help to identify high-risk individuals.

Endothelial Dysfunction does ultimately cause all kinds of problems in later life.  What is relevant to this blog is the potential neurological benefit of improving endothelial function in younger people, if any.
We need to recall that historically there have been very few older people with more severe autism; they did not live to the age when typical problems caused by endothelial dysfunction become apparent. 

Overlapping causes of Endothelial Dysfunction
The interesting question is just how many of the possible causes of endothelial dysfunction occur in autism. 
So far the following factors seem to apply to autism:-
·        Oxidative stress (ROS)

·        Reduced eNOS and nitic oxide (NO)    

·         VEGF (Vascular endothelial growth factor) is disturbed

·         Even estrogen deficiency can play a role and this is reduced in autism
People with autism who use calcium folinate (Leucoverin) are already quenching  Peroxynitrite (ONOO) another factor in Endothelial Dysfunction.                                                               

Is Arginine/Arginase disturbed in Autism?
One well known anomaly in diabetes is a high level of an enzyme called Arginase, resulting in reduced production of nitric oxide (NO) in endothelial cells.
Here again we have to revert to looking at schizophrenia, as the closest thing to autism. Here there are no surprises. 

Previous research implicates altered metabolism of l-arginine, a versatile amino acid with a number of bioactive metabolites, in the pathogenesis of schizophrenia. The present study, for we believe the first time, systematically compared the metabolic profile of l-arginine in the frontal cortex (Brodmann's area 8) obtained post-mortem from schizophrenic individuals and age- and gender-matched non-psychiatric controls (n=20 per group). The enzyme assays revealed no change in total nitric oxide synthase (NOS) activity, but significantly increased arginase activity in the schizophrenia group. Western blot showed reduced endothelial NOS protein expression and increased arginase II protein level in the disease group. High-performance liquid chromatography and liquid chromatography/mass spectrometric assays confirmed significantly reduced levels of γ-aminobutyric acid (GABA), but increased agmatine concentration and glutamate/GABA ratio in the schizophrenia cases. Regression analysis indicated positive correlations between arginase activity and the age of disease onset and between l-ornithine level and the duration of illness. Moreover, cluster analyses revealed that l-arginine and its main metabolites l-citrulline, l-ornithine and agmatine formed distinct groups, which were altered in the schizophrenia group. The present study provides further evidence of altered brain arginine metabolism in schizophrenia, which enhances our understanding of the pathogenesis of schizophrenia and may lead to the future development of novel preventions and/or therapeutics for the disease






Arginine metabolic pathways. l-arginine can be metabolized by NOS, arginase and ADC to form a number of bioactive molecules (see the Introduction for detailed description). We found increased levels of arginase activity, arginase II protein expression and agmatine tissue concentration (indicated by the red letters and arrows), and reduced eNOS protein expression and GABA level (indicated by the green letters and arrows) in the schizophrenia cases. ADC, arginine decarboxylase; BA8, Brodmann's area 8; eNOS, endothelial NOS; GABA, γ-aminobutyric acid; iNOS, inducible NOS; NO, nitric oxide; NOS, nitric oxide synthase; nNOS, neuronal NOS.  

It is of interest to note that the plasma agmatine level was increased over threefold in schizophrenic patients relative to healthy controls



The present study, interestingly, found an over 50% increase in arginase activity in BA8 accompanied by a significant upregulation of arginase II in the schizophrenia group. It is currently unclear how arginase changes in blood correlate with those in the brain tissue

Polyamines and agmatine have also been implicated in psychiatric disorders


L-Norvaline for Aspie1983?
One reader has raised issue of whether L-Norvaline would be a good idea.
L-Norvaline is an arginase inhibitor, used by body builders to increase nitric oxide.
L-arginine is used as a substrate by both nitric oxide synthase (NOS) and arginase to produce nitric oxide (NO) and urea, respectively.
If you inhibit arginase you shift the L-arginine over towards nitric oxide production.
People with diabetes and, as we saw above schizophrenia, have elevated levels of arginase. This will cause them to have a reduced level of nitric oxide. Reduced nitric oxide will contribute to Endothelial Dysfunction.
So it looks like L-Norvaline might well be beneficial in diabetes and schizophrenia.
L-Norvaline  might slow the conversion of ammonia to urea, if arginase was low to start with.  If arginase was elevated to start with you might expect no impact on the conversion of ammonia to urea.


Agmatine, Polyamines & L-citrulline 
Agmatine may already be elevated in schizophrenia, but it looks like a little extra can be beneficial in autism.
Polyamines can also be good for you if they increase autophagy. Which specific polyamine you want is an open question.
In the schizophrenia study L-citrulline is reduced. This makes sense because L-arginine has been shifted over towards  urea by elevated arginase. L-citrulline is a byproduct when nitric oxide (NO) is produced.
Perhaps unexpectedly, l-Citrulline is also a potent endogenous precursor of l-arginine. In a recent clinical study, l-citrulline supplementation dose-dependently increases plasma l-arginine levels in healthy human volunteers more effectively than equivalent doses of l-arginine itself.
Aspie1983 might not need to supplement L-citrulline, if he used L-Norvaline .

Altered brain arginine metabolism in autism?
I suspect Aspie1983 is not the only one with an altered brain arginine metabolism.
There appear to be many therapeutic options and they are all body building supplements because they will all increase nitric oxide (NO).
They will all improve Endothelial Dysfunction, which was the original subject of this post.

Conclusion
It certainly seems like Endothelial Dysfunction is present in some autism and that numerous established therapies should help.
We are already targeting oxidative stress with antioxidants and some people use calcium folinate that will target nitrosative stress.
The therapies that increase NO and/or eNOS include:-
·        Agmatine

·        L-arginine

·        L-citrulline

·        L- norvaline

·        Cocoa flavanols

·        Beetroot juice

·        L-taurine does increase eNOS and NO, but it is not clear how

There are products sold to body builders that include several of these and some clever additional ones.

Like this one, 12 grams made up of:-
1.   L-Citrulline
2.   L-Taurine
3.   Agmatine Sulfate 
4.   Glycerol Monostearate
5.   Dan-Shen, a Chinese cardio-protective herb that increases NO and also behaves like low dose aspirin
6.   Beetroot Powder
7.   L-Norvaline
8.   Hesperidin, a citrus flavonoid that increases NO
9.   Black pepper extract; piperine is known to affect NO release


Dan-Shen :- there are numerous clinical trials on Dan-Shen and its active ingredient. It has even been suggested to treat PANS/PANDAS.

These clinical trials include treating altitude sickness.

Hesperiden is found in oranges and indeed peppermint, but in oranges it is most abundant in the white inner part of the peel. Orange peel is a home remedy to lower cholesterol. Research shows that Hesperiden (and naringin) is a potent cholesterol lowering substance.

You would think that you can have too much of a good thing, that is too much endothelial nitric oxide; ask a body builder.
There is more to this subject, beyond the body builder’s science; the related areas to look at are angiogenesis and lymphangiogenesis. These are very much influenced by VEGF (Vascular Endothelial Growth Factor). In the next post we will see that there is evidence suggesting blood vessel growth can be unchecked in some autism resulting in unstable blood flow, not simply reduced flow.
So while the view from today’s post is that in autism there may be restricted blood flow, rather like in vascular dementia, the real situation is likely more complex.
We also have the issue of how the lymphatic system, that collects waste materials from the body (including the brain), may also be affected. With blood vessels there may be “too much growth” but in the case of lymphatic system there may be too little. This is all governed by VEGF.
We have already seen that autophagy and mitophagy are reduced in some autism and are a defining feature of Huntingdon’s Disease. Accumulation of waste products in the brain has consequences. Improved autophagy, possible via the same polyamines referred to in the earlier graphic, and improved lymphangiogenesis could be therapeutic. It appears that the brain flushes out waste products to the lymphatic system while you sleep; Alzheimer's is most prevalent in people who sleep very little.