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Showing posts with label Ibudilast. Show all posts
Showing posts with label Ibudilast. Show all posts

Tuesday, 15 January 2019

More Myelin? Or just Better Myelination - Intelligence, PDE4 and Clemastine again




Myelination in the Central Nervous System (CNS)                  Oligodendrocyte myelinating multiple axons

The previous post on myelin was this one.


In that post we saw that you can activate P2X7 receptors with an antihistamine called Clemastine and you can block P2X7 with another cheap antihistamine called Oxatomide. The P2X7 receptor plays a role in both inflammation and myelination and this receptor appears to be linked to neurological disorders including schizophrenia and even depression.
In that post I also compared experimental MS therapies with experimental autism therapies.




The yellow box means, we know it works, at least for some people, based on trial results.

The widely available PDE4 inhibitor, Roflumilast, has been patented as a cognitive enhancer, but even at that lower dose it can make people vomit.  Ibudilast seems to have fewer side effects and is under investigation in the US to treat MS, but is currently only approved in Japan and as an asthma therapy.
The logical next step is to investigate the two P2X7 modifying antihistamines, which should have opposing effects.
Oxatomide is widely used in Italy. Clemastine is OTC in the US and the UK.
I did some more investigation of Clemastine and came across some encouraging reports of off-label use in psychiatry at modest doses. Off label use to treat MS at high doses was associated with quite negative reports, due to the sedating effect, which is inevitable with antihistamines that can cross the blood brain barrier.
Today’s post goes into more detail about myelination and concludes with the open question of who might actually benefit from a half dose of clemastine, (Dayhist in the US, Tavegil in the UK); clearly some people do already benefit. 
At least one US child psychiatrist is a fan and the research suggests many conditions might benefit, ranging from severe to more trivial.  At 15-20 times higher dosage, clemastine is proposed as a therapy for Multiple Sclerosis (MS), but at that dosage clemastine is highly sedating. High dose clemastine might be a potential immediate response to the onset of regression in autism and CDD (Childhood Disintegrative Disorder).
Clemastine and Ibudilast have different modes of action. Clemastine works by activating P2X7 receptors in oligodendrocytes (in the CNS) and schwann cells (in the PNS) to make more myelin.
PDE4 inhibitors cause enhanced differentiation of OPCs (oligodendrocyte progenitor cells). OPC are precursors to oligodendrocytes.
So Roflumilast and Ibudilast should make more oligodendrocytes, while clemastine just kicks the ones you already have to work harder.  So in any one person the effect of these two types of drug may very well differ. 
Also, note that myelin needs to be constantly repaired in a process naturally called remyelination. So really we are just trying to benefit from improving this already existing repair service.

Some relevant background information:



“Myelination is only prevalent in a few brain regions at birth and continues into adulthood. The entire process is not complete until about 25–30 years of age. Myelination is an important component of intelligence. Neuroscientist Vincent J. Schmithorst proposes that there is a correlation with white matter and intelligence. People with greater white matter had higher IQs. A study done with rats by Janice M. Juraska showed that rats that were raised in an enriched environment had more myelination in their corpus callosum. 
In cerebral palsy, spinal cord injury, stroke and possibly multiple sclerosis, oligodendrocytes are thought to be damaged by excessive release of the neurotransmitter, glutamate. Damage has also been shown to be mediated by N-methyl-D-aspartate receptors. Oligodendrocyte dysfunction may also be implicated in the pathophysiology of schizophrenia and bipolar disorder.”

The role of myelin
Myelin has been compared to the insulation on electrical cables.  If only it was that simple, there would not be so many genes involved in the process.

Nodes of Ranvier do matter
If you look at the above graphic of a neuron you will see gaps in the myelin, that are called Nodes of Ranvier.
The electrical signal does not pass along the axon like a piece of copper wire, rather it jumps from one Node of Ranvier to the next, in a process called saltatory conduction.
Also each subsequent piece of myelin along the length of an axon is connected to a different oligodendrocyte. Otherwise there would be no electrical conduction possible; there has to be a “potential difference” for a current to flow.
Each oligodendrocyte can be connected to 50 different pieces of myelin, many on different axons. Just imagine what that looks like; forget the spaghetti of cables connected to your TV, this is something really jumbled up.
If the electrical signal jumps to an adjacent axon rather than jumping along the same axon, there will be a problem.
If there is too much myelin produced you might squeeze out the node of Ranvier and then the signal cannot pass along to the next neuron.



Myelination Defects in Autism
We have already seen in previous posts that myelination is often found to be abnormal in autism.
A very thorough recent study looked at myelination in a number of single gene autisms. The conclusion was that in these very different types of autism there was a common theme of defective myelination.
This adds further weight to the idea of considering impaired myelination a key feature of much autism.
Loss of myelination has been suggested to be a core feature of regressive autism and I propose a very likely driver of Childhood Disintegrative Disorder (CDD).
“Improving myelination” rather than simply “more myelination” might well be very helpful to many types of severe autism. It seems that even in much milder neurological conditions improving myelination can be therapeutic.
The usual target of experimental myelination therapies is Multiple Sclerosis (MS), it may also be the hardest to treat.
Some researchers and clinicians are repurposing MS therapies for other neurological disorders, either in mouse models or in humans.  This seems like a very good idea to me. 

One Sentence Summary: RNA sequencing of seven syndromic autism mouse models identify myelination genes disrupted in human ASD.

Autism Spectrum Disorder (ASD) is genetically heterogeneous in nature with convergent symptomatology, suggesting dysregulation of common molecular pathways. We analyzed transcriptional changes in the brains of five independent mouse models of Pitt-Hopkins Syndrome (PTHS), a syndromic ASD caused by autosomal dominant mutation in TCF4, and identified considerable overlap in differentially expressed genes (DEGs). Gene and cell-type enrichment analyses of these DEGs identified oligodendrocyte dysregulation that was subsequently validated by decreased protein levels. We further showed significant enrichment of myelination genes was prevalent in two additional mouse models of ASD (Ptenm3m4/m3m4, Mecp2KO). Moreover, we integrated syndromic ASD mouse model DEGs with ASD risk-gene sets (SFARI) and human idiopathic ASD postmortem brain RNA-seq and found significant enrichment of overlapping DEGs and common biological pathways associated with myelination and oligodendrocyte differentiation. These results from seven independent mouse models are validated in human brain, implicating disruptions in myelination is a common ASD pathophysiology.

To address these questions, we performed integrative transcriptomic analyses of seven independent mouse models of three syndromic forms of ASD generated across five laboratories, and assessed dysregulated genes and their pathways in human postmortem brain from patients with ASD and unaffected controls. These cross-species analyses converged on shared disruptions in myelination and axon development across both syndromic and idiopathic ASD, highlighting both the face validity of mouse models for these disorders and identifying novel convergent molecular phenotypes amendable to rescue with therapeutics. 

Shared myelination gene regulation between mouse models of syndromic ASD. Venn diagram of DEGs (differentially expressed genes) in each mouse model of ASD




Top GO (Gene ontology) terms of the CAGs (convergent ASD genes) enrich for myelination processes



P2X purinoceptor 7 is a protein that in humans is encoded by the P2RX7 gene.

The product of this gene belongs to the family of purinoceptors for ATP. Multiple alternatively spliced variants which would encode different isoforms have been identified although some fit nonsense-mediated decay criteria.
The receptor is found in the central and peripheral nervous systems, in microglia, in macrophages, in uterine endometrium, and in the retina. The P2X7 receptor also serves as a pattern recognition receptor for extracellular ATP-mediated apoptotic cell death, regulation of receptor trafficking, mast cell degranulation, and inflammation.


Our findings point to P2X7R as a potential therapeutic target in schizophrenia.


The P2X7 purinergic receptor: An emerging therapeutic target in cardiovascular diseases

The P2X7 purinergic receptor, a calcium permeable cationic channel, is activated by extracellular ATP. Most studies show that P2X7 receptor plays an important role in the nervous system diseases, immune response, osteoporosis and cancer. Mounting evidence indicates that P2X7 receptor is also associated with cardiovascular disease. For example, the P2X7 receptor activated by ATP can attenuate myocardial ischemia-reperfusion injury. By contrast, inhibition of P2X7 receptor decreases arrhythmia after myocardial infarction, prolongs cardiac survival after a long term heart transplant, alleviates the dilated cardiomyopathy and the autoimmune myocarditis process. The P2X7 receptor also mitigates vascular diseases including atherosclerosis, hypertension, thrombosis and diabetic retinopathy. This review focuses on the latest research on the role and therapeutic potential of P2X7 receptor in cardiovascular diseases.

Clemastine is an extracellularly binding allosteric P2X7 receptor modulator.
Clemastine can potentiate the sensitivity of P2X7 to lower ATP concentrations. Additionally, clemastine increases the release of IL-1β from macrophages. Thus, clemastine may be a potential P2X7 activator.

Brain ischemia leading to stroke is a major cause of disability in developed countries. Therapeutic strategies have most commonly focused on protecting neurons from ischemic damage. However, ischemic damage to white matter causes oligodendrocyte death, myelin disruption, and axon dysfunction, and it is partially mediated by glutamate excitotoxicity. We have previously demonstrated that oligodendrocytes express ionotropic purinergic receptors. The objective of this study was to investigate the role of purinergic signaling in white matter ischemia. We show that, in addition to glutamate, enhanced ATP signaling during ischemia is also deleterious to oligodendrocytes and myelin, and impairs white matter function. Thus, ischemic oligodendrocytes in culture display an inward current and cytosolic Ca(2+) overload, which is partially mediated by P2X7 receptors. Indeed, oligodendrocytes release ATP after oxygen and glucose deprivation through the opening of pannexin hemichannels. Consistently, ischemia-induced mitochondrial depolarization as well as oxidative stress culminating in cell death are partially reversed by P2X7 receptor antagonists, by the ATP degrading enzyme apyrase and by blockers of pannexin hemichannels. In turn, ischemic damage in isolated optic nerves, which share the properties of brain white matter, is greatly attenuated by all these drugs. Ultrastructural analysis and electrophysiological recordings demonstrated that P2X7 antagonists prevent ischemic damage to oligodendrocytes and myelin, and improved action potential recovery after ischemia. These data indicate that ATP released during ischemia and the subsequent activation of P2X7 receptor is critical to white matter demise during stroke and point to this receptor type as a therapeutic target to limit tissue damage in cerebrovascular diseases.

Clemastine as a practical intervention
I came across a discussion among MS sufferers and a specific comment from a US child psychiatrist that drew my attention.


Daniel Kerlinsky says:   september 1 1, 2018 at 123 AM

Clemastine is a highly effective medication for re-myelination of white matter fiber bundles that connect neurons everywhere in the brain.
High doses aren't needed. One quarter of a 2.68 mg tablet is enough to start recruiting new oligodendrocytes to start making and applying myelin.
It does not have to be taken every day; it can be taken twice a week and still have a positive effect by recruiting the worker cells that repair the brain.
Remember normal myelination starts at the top of the brain and works downward during childhood development. At first the baby can't hold its head up, then it can sit up, then crawl, then stand.
Many MS lesions are located further down inside the brain and spinal cord so it takes time to get there.
The anti-inflammatory Minocycline taken once or twice a week is needed to stop the inflammatory part of the disease.                                                                            
And it takes cranio-sacral therapy to take full advantage of the new myelin which plumps the brain and even lubricates stiff joints like the sphenoid-occipital junction.
Don't give up on clemastine.

Its first and most obvious effect is improved emotional self regulation. Because myelination increases the speed of information processing ten-fold you will notice that thinking better comes next.
I can't tell you how long it will take to notice a difference. But the MS patient who told me about Clemastine got up out of her electric wheel chair and walked down the hall and back without a walker or her canes for the first time in two years.
It works great for kids with tantrums and developmental problems in about a month. It helps people with chronic depression and PTSD in about three months.
Back your dose down to 1.34 mg or 0.67 mg and give it two years. It takes a toddler that long.„



Increasing evidence suggests that white matter disorders based on myelin sheath impairment may underlie the neuropathological changes in schizophrenia. But it is unknown whether enhancing remyelination is a beneficial approach to schizophrenia. To investigate this hypothesis, we used clemastine, an FDA-approved drug with high potency in promoting oligodendroglial differentiation and myelination, on a cuprizone-induced mouse model of demyelination. The mice exposed to cuprizone (0.2% in chow) for 6 weeks displayed schizophrenia-like behavioral changes, including decreased exploration of the center in the open field test and increased entries into the arms of the Y-maze, as well as evident demyelination in the cortex and corpus callosum. Clemastine treatment was initiated upon cuprizone withdrawal at 10 mg/kg per day for 3 weeks. As expected, myelin repair was greatly enhanced in the demyelinated regions with increased mature oligodendrocytes (APC-positive) and myelin basic protein. More importantly, the clemastine treatment rescued the schizophrenia-like behavioral changes in the open field test and the Y-maze compared to vehicle, suggesting a beneficial effect via promoting myelin repair. Our findings indicate that enhancing remyelination may be a potential therapy for schizophrenia.

Altered myelin structure and oligodendrocyte function have been shown to correlate with cognitive and motor dysfunction and deficits in social behavior. We and others have previously demonstrated that social isolation in mice induced behavioral, transcriptional, and ultrastructural changes in oligodendrocytes of the prefrontal cortex (PFC). However, whether enhancing myelination and oligodendrocyte differentiation could be beneficial in reversing such changes remains unexplored. To test this hypothesis, we orally administered clemastine, an antimuscarinic compound that has been shown to enhance oligodendrocyte differentiation and myelination in vitro, for 2 weeks in adult mice following social isolation. Clemastine successfully reversed social avoidance behavior in mice undergoing prolonged social isolation. Impaired myelination was rescued by oral clemastine treatment, and was associated with enhanced oligodendrocyte progenitor differentiation and epigenetic changes. Clemastine induced higher levels of repressive histone methylation (H3K9me3), a marker for heterochromatin, in oligodendrocytes, but not neurons, of the PFC. This was consistent with the capability of clemastine in elevating H3K9 histone methyltransferases activity in cultured primary mouse oligodendrocytes, an effect that could be antagonized by cotreatment with muscarine. Our data suggest that promoting adult myelination is a potential strategy for reversing depressive-like social behavior.

SIGNIFICANCE STATEMENT Oligodendrocyte development and myelination are highly dynamic processes influenced by experience and neuronal activity. However, whether enhancing myelination and oligodendrocyte differentiation is beneficial to treat depressive-like behavior has been unexplored. Mice undergoing prolonged social isolation display impaired myelination in the prefrontal cortex. Clemastine, a Food and Drug Administration-approved antimuscarinic compound that has been shown to enhance myelination under demyelinating conditions, successfully reversed social avoidance behavior in adult socially isolated mice. This was associated with enhanced myelination and oligodendrocyte differentiation in the prefrontal cortex through epigenetic regulation. Thus, enhancing myelination may be a potential means of reversing depressive-like social behavior.



BACKGROUND:

Multiple sclerosis is a degenerative inflammatory disease of the CNS characterised by immune-mediated destruction of myelin and progressive neuroaxonal loss. Myelin in the CNS is a specialised extension of the oligodendrocyte plasma membrane and clemastine fumarate can stimulate differentiation of oligodendrocyte precursor cells in vitro, in animal models, and in human cells. We aimed to analyse the efficacy and safety of clemastine fumarate as a treatment for patients with multiple sclerosis.

METHODS:


We did this single-centre, 150-day, double-blind, randomised, placebo-controlled, crossover trial (ReBUILD) in patients with relapsing multiple sclerosis with chronic demyelinating optic neuropathy on stable immunomodulatory therapy. Patients who fulfilled international panel criteria for diagnosis with disease duration of less than 15 years were eligible. Patients were randomly assigned (1:1) via block randomisation using a random number generator to receive either clemastine fumarate (5·36 mg orally twice daily) for 90 days followed by placebo for 60 days (group 1), or placebo for 90 days followed by clemastine fumarate (5·36 mg orally twice daily) for 60 days (group 2). The primary outcome was shortening of P100 latency delay on full-field, pattern-reversal, visual-evoked potentials. We analysed by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT02040298.

FINDINGS:


Between Jan 1, 2014, and April 11, 2015, we randomly assigned 50 patients to group 1 (n=25) or group 2 (n=25). All patients completed the study. The primary efficacy endpoint was met with clemastine fumarate treatment, which reduced the latency delay by 1·7 ms/eye (95% CI 0·5-2·9; p=0·0048) when analysing the trial as a crossover. Clemastine fumarate treatment was associated with fatigue, but no serious adverse events were reported.

INTERPRETATION:


To our knowledge, this is the first randomised controlled trial to document efficacy of a remyelinating drug for the treatment of chronic demyelinating injury in multiple sclerosis. Our findings suggest that myelin repair can be achieved even following prolonged damage.



Drug: Clemastine

12mg (4mg 3x/day) clemastine for 7 days followed by 8mg clemastine (4mg 2x/day) until 3 months. Patients will be off treatment from 3-9 months and will be reevaluated at 9 months.



Conclusion
Hopefully this post takes us one step closer to finding safe, side effect free, inexpensive ways to improve myelination in those with impaired myelination.

In the case of treating Multiple Sclerosis (MS), side effects clearly remain an issue. The suggestion of the psychiatrist in today’s post is to just lower the clemastine dosage and give it some time (2 years).  That sounds like smart advice to me.
Fortunately, it appears that in less severe cases of impaired myelination you may not need to wait 2 years.

Who exactly is going to benefit remains an open question, but for people already using H1 antihistamines to treat allergy, or other mast cell activation, switching to a different OTC antihistamine drug does not look like such a big step to take.
People with schizophrenia and allergy also might want to consider switching their antihistamine.

Undoubtedly some people will have the opposite issue with P2X7 receptors and for them there is another old antihistamine drug called Oxatomide.




Thursday, 9 August 2018

Ketones and Autism Part 3 - Niacin Receptor HCA2/GPR109A in Autism, Colonic Inflammation, Psoriasis and Multiple Sclerosis





 Repurposing a German psoriasis treatment for the second time?
First for Multiple Sclerosis and second for some Autism?

Today’s post is about one anti-inflammatory aspect of ketones; part 4 in this series will look at Ketones and their effect on the NLRP3 inflammasome, which also relates to inflammation; but it would be too much for one post. If you have elevated levels of the inflammatory cytokine IL-1β, common in much autism and Alzheimer’s, part 4 of this series will be very relevant.
Today we just look at HCA2, which should be interesting for people with Multiple Sclerosis (MS), psoriasis and anyone with autism who responds to HCA2 activation.
In Germany a tailor-made solution already exists for a potential clinical trial to evaluate the effect of HCA2 activation; and even with low dose tablets.
Activating HCA2 should have profound neuroprotective effects; the ways to activate it include: -

·        BHB (β-hydroxybutyrate) from the ketogenic diet

·        Butyric acid produced by bacteria and fiber in your intestines (or by eating rancid butter, or Tibetan Yak butter tea)

·        Butyrate supplements

·        Niacin (Vitamin B3 /nicotinic acid)

·        Dimethyl fumarate (an ultra-expensive US drug called Tecfidera, or an old German drug called Fumaderm) 

Activating HCA2 inside the gut can be used to reduce colonic inflammation; for this you would need your HCA2 activator to be in your colon, so the ketogenic diet would not help whereas fiber and the right probiotic bacteria would help.
For some autism and multiple sclerosis, you would think we just want to activate HCA2 receptors in the brain, but it may not be so simple.
There is no perfect solution to activate HCA2, mainly because it can cause flushing. 
The flushing effect is due to HCA2 activation of ERK 1/2 MAP kinase. Activation of MAP kinase in turn causes release of prostaglandin D2 (PGD2) from Langerhans cells in the skin and this causes flushing. 
The same PGD2 released in the brain is metabolized to another substance, 15-d-PGJ(2), which is a PPARϒ agonist.  PPAR gamma has been covered elsewhere in this blog, because agonists should be beneficial in some autism, however using a tangeretin/nobiletin supplement, that is a mild PPARϒ agonist, the positive effect lasts just a few days.
There are potent new drugs in development that may avoid flushing.


All the above options have other effects.
BHB from BHB supplements inevitably contain large amounts of Ca, K, Na or Mg, which will have their own effects.
Niacin causes flushing at higher doses.
Butyric acid has many potential beneficial effects, but too much may have some negative effects, at least in some people. It is an HDAC inhibitor, giving potential epigenetic effects.
Dimethyl fumarate (DMF) is likely the most potent current HCA2 agonist and can work wonders for severe psoriasis, some arthritis and some multiple sclerosis, but at these high doses does have some side effects.
Dimethyl fumarate (DMF) for psoriasis is not a cream, rather a coated tablet, the kind you are not supposed to cut in half. The adult dose can be 240mg three times a day, but as you can see in the photo at the start of this blog a 30mg tablet exists.  So, a practical low dose Dimethyl fumarate exists as a mild HCA2 agonist, but quite possibly it is more potent than niacin.
DMF as a drug is a bit pricey in Germany and exorbitantly expensive in the US. DMF as a chemical is very cheap. 

HCA2 and Neuroinflammation                       

Much is already known about how activating HCA2 can reduce neuroinflammation.
Putting out the fire, so to speak, is doubly important in much autism because inflammation makes chloride levels rise inside neurons (via increasing NKCC1 and reducing KCC2 expression). Elevated chloride levels make the neurotransmitter GABA work “in reverse” as excitatory; our current drug, bumetanide, to lower chloride levels lacks potency. If inflammation increases there comes a point when bumetanide no longer is able to maintain chloride at a low enough level; it then appears as “bumetanide has stopped working”. 

Nutritional or pharmacological activation of HCA (2) ameliorates neuroinflammation.


Neuroinflammation is a pathology common to many neurological diseases, including multiple sclerosis (MS) and stroke. However, therapeutic attempts to modulate neuroinflammation have proved difficult. Neuroinflammatory cells express HCA2, a receptor for the endogenous neuroprotective ketone body β-hydroxybutyrate (BHB) as well as for the drugs dimethyl fumarate (DMF) and nicotinic acid, which have established efficacy in the treatment of MS and experimental stroke, respectively. This review summarizes the evidence that HCA2 is involved in the therapeutic effects of DMF, nicotinic acid, and ketone bodies in reducing neuroinflammation. Furthermore, we discuss the mechanisms underlying the beneficial effects of HCA2 activation in neuroinflammatory diseases and the therapeutic potential of recently developed synthetic ligands of HCA2.

  



Figure 1. Potential anti-neuroinflammatory role of HCA2 as a target of monomethyl fumarate (MMF) and nicotinic acid (NA).  Based on the expression of HCA2 in neutrophils, monocytes, macrophages, and dendritic cells, several mechanisms underlying the immunomodulatory and anti-inflammatory effects of MMF and NA can be envisioned.  Both drugs may have systemic effects on monocytes, macrophages, or neutrophils outside the central nervous system (CNS) (1) that indirectly affect neuroinflammatory processes by altering the capacity of immune cells to enter the CNS or to promote neuroinflammation. There is also evidence that MMF and NA are able to directly inhibit neutrophil and possibly also monocyte infiltration through the blood–brain barrier (2) and they may also affect their inflammatory function within the CNS (3).  Finally, as antigen-presenting cells (APCs) that reactivate T cells in the perivascular space may also express HCA2, inhibition of APC function through HCA2 may contribute to the anti-neuroinflammatory effects of HCA2 agonists (4).





Figure 3. HCA2 mediates the neuroprotective effect of b-hydroxybutyrate (BHB).  On a normal diet, glucose (from the blood) serves as the main energy substrate of the brain (green arrows).  It is transported by GLUT1 over the blood–brain barrier (BBB) and metabolized. During fasting, adipocytes release large quantities of free fatty acids (FFAs) from stored triglycerides (TGs) (red arrows).  Alternatively, a high-fat, low-carbohydrate ketogenic diet leads to elevated FFA supply.  In the liver FFAs are metabolized to the ketone bodies acetoacetate (AcAc) and BHB.  In a negative feedback circuit, BHB binds to its receptor HCA2 on adipocytes and inhibits the release of TG. In the periphery, or after being transported into the central nervous system (CNS) by monocarboxylate transporter (MCT) 1 or 2, BHB also binds to HCA2 on neutrophils, microglia, and monocyte-derived cells and dampens neuroinflammation.  In addition, BHB is a substrate for mitochondrial energy production in neurons. 

BHB is not only a metabolic intermediate but also a signaling molecule that activates HCA2 and inhibits the G protein-coupled receptor GPR41 and histone deacetylase (HDAC) 1, 3, and 4 [94,95]. This led to the hypothesis that BHB induces neuroprotective effects through specific actions on receptors or enzymes. The IC50 values for inhibition of HDAC and GPR41 by BHB are higher than the EC50 for activation of HCA2 [94,95], suggesting HCA2 as the preferred target when BHB levels rise. 



The ketone body β-hydroxybutyrate (BHB) is an endogenous factor protecting against stroke and neurodegenerative diseases, but its mode of action is unclear. Here we show in a stroke model that the hydroxy-carboxylic acid receptor 2 (HCA2, GPR109A) is required for the neuroprotective effect of BHB and a ketogenic diet, as this effect is lost in Hca2(-/-) mice. We further demonstrate that nicotinic acid, a clinically used HCA2 agonist, reduces infarct size via a HCA2-mediated mechanism, and that noninflammatory Ly-6C(Lo) monocytes and/or macrophages infiltrating the ischemic brain also express HCA2. Using cell ablation and chimeric mice, we demonstrate that HCA2 on monocytes and/or macrophages is required for the protective effect of nicotinic acid. The activation of HCA2 induces a neuroprotective phenotype of monocytes and/or macrophages that depends on PGD2 production by COX1 and the haematopoietic PGD2 synthase. Our data suggest that HCA2 activation by dietary or pharmacological means instructs Ly-6C(Lo) monocytes and/or macrophages to deliver a neuroprotective signal to the brain.
  
DMF and MMF
DMF (Dimethyl fumarate) is in effect a prodrug, it is converted in the body by our friendly antioxidant glutathione (GSH) into MMF (monomethyl fumarate).
It is MMF that is the active substance.
DMF has long been used as a drug to treat severe psoriasis, an inflammatory condition of the skin. It was later found that in people psoriasis and MS, that when they took DMF for their skin problem their multiple sclerosis symptoms reduced.

DMF and Niacin for Multiple Sclerosis
Since we assume that DMF improves MS by activating HCA2, it would be logical to look at the effect of other activators of this niacin channel in MS.
You do not have to look far to find the so-called Klenner Protocol for MS, which treats it with large doses of niacin


We now have a hugely expensive FDA approved therapy for MS, based on the DMF used in Germany to treat psoriasis.
What about other HCA2 activators? Perhaps some in your kitchen?
Here is one long list: - 


One that caught my eye was Cinnamic Acid. Sure, it has less affinity for the receptor than some of the other substances, but it is an HCA2 activator.
When you eat cinnamon, the cinnamaldehyde present is converted into cinnamic acid by oxidation. In the liver, this cinnamic acid is β-oxidized to benzoate that exists as sodium benzoate.                                                                                           


Phenolic acids are found in abundance throughout the plant kingdom. Consumption of wine or other rich sources of phenolic acids, such as the “Mediterranean diet,” has been associated with a lower risk of cardiovascular disease. The underlying mechanism(s), however, has remained unclear. Here, we show that many phenolic acids, including those from the hydroxybenzoic and hydroxycinnamic acid classes, can bind and activate GPR109A (HM74a/PUMA-G), the receptor for the antidyslipidemic agent nicotinic acid. In keeping with this activity, treatment with a number of phenolic acids, including cinnamic acid, reduces lipolysis in cultured human adipocytes and in fat pats isolated from wild-type mice but not from mice deficient of GPR109A. Oral administration of cinnamic acid significantly reduces plasma levels of FFA in the wild type but not in mice deficient of GPR109A. Activation of GPR109A by phenolic acids may thus contribute to a cardiovascular benefit of these plant-derived products. 

Our data clearly show that many of the phenolic acids could act as ligands of the nicotinic acid receptor GPR109A, and activation of GPR109A by the phenolic compounds leads to a reduction of adipocyte lipolysis. Activation of GPR109A may lead to differential downstream effects on lipolysis and flushing response. For example, a number of GPR109A pyrazole agonists were found capable of inhibiting lipolysis but failed to elicit a flushing response and can antagonize nicotinic-acid-mediated flushing response (22). It is unclear if any of the phenolic acids from plant products, such as wine, could function as pyrazole agonist of GPR109A, thus leading to an escape of a flushing res

Phenolic acids are highly present in the Mediteranean Diet and so you might wonder if this diet is protective.  Apparently it is.

Mediterranean diet (MD) adherence and risk of multiple sclerosis: a case-control study.

CONCLUSIONS:


Our study suggests that a high quality diet assessed by MD may decrease the risk of MS.

So how about cinnamon as a home remedy for MS? Well is seems to help mice with MS. 

Although the central nervous system (CNS) is separated from the immune system by blood-brain barrier and traditionally considered “immune privileged”, our immune cells are capable of targeting the brain, leading to the development of CNS autoimmune disorders. Multiple sclerosis (MS) is one such autoimmune disorder of the CNS in which myelin components are particularly targeted by the immune system resulting in demyelination of axons and associated debilitating symptoms [13]. In spite of intense investigations, no effective therapy is available for this disease. Therefore, a safe and effective therapeutic option is necessary for MS.
Fortunately, we have been endowed with enormous natural remedies to take care our health issues. For example, cinnamon, the brown bark of cinnamon tree, that has already been being used for centuries throughout the world as spice or flavouring agent. Furthermore, medieval physicians used cinnamon for medical purposes to treat a variety of disorders including arthritis, coughing, hoarseness, sore throats, etc. Recent studies are indicating that this natural product may be helpful for MS [46]. Although the etiology of MS is poorly understood, it is becoming clear that widespread inflammation, loss of regulatory T cells (Tregs), hyperactivity of autoimmune Th1 and Th17 cells, breakdown of blood-brain barrier (BBB) and blood-spinal cord barrier (BSB), and loss of neuroprotective molecules in the CNS are critical for the manifestation of demyelinating pathology in MS [13]. Interestingly, cinnamon treatment is capable of modifying these pathological features in mice with experimental allergic encephalomyelitis (EAE), an animal model of MS [4,6].



Highlights

·        DMF may act in neurodegeneration and inflammation by activating the Nrf2 pathway. 
·        DMF and MMF downregulates the immune response through HCA2/GPR109A pathway. 
·        Nrf2 and HCA2/GPR109A pathways activation may explain DMF’s efficacy and safety profile.  

Conclusion: Although the DMF/MMF mechanism of action remains unclear, evidence suggests that the activation of HCA2/GPR109A pathway downregulates the immune response and may activate anti-inflammatory response in the intestinal mucosa, possibly leading to reduction in CNS tissue damage in MS patients.

The mechanisms of action of MMF and DMF are not well understood, but a growing body of evidence has demonstrated that DMF may act on both the neurodegenerative and inflammatory response of MS patients. The majority of the data related to the mechanism of action of DMF/MMF demonstrates the association of the compounds with the activation of the nuclear factor-(erythroid-derived 2) related factor 2 (Nrf2) pathway. Nrf2 activation leads to a type II antioxidant response, reducing both inflammatory responses and oxidative stress 11, which play a major role in demyelination and neurodegeneration in MS.   
In addition to the Nrf-2 signaling pathway, recent observations demonstrated that MMF/DMF could also downregulate the immune response through a on-Nrf2 related pathway. MMF has been shown to be an agonist of the hydroxycarboxylic acid receptor 2 (HCA2) signaling pathway, also known as niacin receptor 1 or nicotinic acid receptor GPR109A.12-14 Thus, it appears that DMF could also activate HCA2/GPR109A in addition to its effects on the Nrf2 pathway (unpublished data, Biogen). In this communication, we discuss DMF/MMF-induced HCA2/GPR109A pathway activation and its implications in the immune response and treatment of MS.  

Moreover, Parodi and colleagues described a novel HCA2/GPR109A signaling pathway modulating microglial activation in an in vitro study .13 MMF binding to HCA2/GPR109A led to subsequent activation of the G1-type G protein signaling cascade by a possible release of the  subunit of G-protein. The increase of Ca2+ induced the activation of AMP-activated protein kinase (AMPK) by calcium/modulin–dependent protein kinase 2 (CaMKK2). In addition, the authors provided evidence that AMPK activation led to an increase in NAD+ generation through phospho-AMPK (pAMPK) and finally activation of SIRT1 (sirtuin 1), which resulted in further inhibition of NF-kB signaling. NF-kB inhibition suppresses pro-inflammatory cytokines and reduces the migration of immune cells into the CNS in the EAE model. In addition, cultured microglial cells also showed reduced pro-inflammatory responses contributing to regulation of synaptic activity.13 All these previous data confirm that both DMF and/or MMF are effective in reducing the severity of EAE.  

A growing body of evidence suggests that nutrition and bacterial metabolites might impact the systemic immune response in autoimmune diseases, such as MS and its experimental models.33 Mucosal tolerance studies have shown that activation of tolerogenic intestinal immune cells can reduce the inflammatory response of autoimmune disease in the CNS.34 The oral administration of myelin basic protein (MBP) significantly reduced the severity of EAE34, at the same time activating and increasing the frequency of TGFβ-producing regulatory T-cells in the gut.35 HCA2/GPR109A is a receptor for butyrate and mediates some of beneficial effects of short-chain fatty acids produced by the gut microbiota.36 Ongoing microbiome studies have highlighted the importance of commensal bacteria both in induction and suppression of autoimmune diseases and this is being actively studied as a potential target for the treatment of immune-mediated maladies.37 A previous study demonstrated that administration of short-chain fatty acids to mice with EAE ameliorated symptomatic disease and reduced axonal damage through activation of regulatory T cells (T-reg) in intestinal mucosa.33 Other studies demonstrated that G protein-coupled receptors such as HCA2/GPR109A are potentially involved in increased extrathymic differentiation of T-reg cells. The activation of HCA2/GPR109A by butyrate metabolites from commensal microbiota increased the generation of colonic Tregs.38 Also, HCA2/GPR109A signaling promoted anti-inflammatory properties in colonic macrophages and dendritic cells and enabled them to induce differentiation of T-reg cells, which suppress colonic inflammation and carcinogenesis.39 The same study demonstrated that the activation of HCAR2 receptors is crucial to generate T-regs since colonic DCs and macrophages from Niacr1−/− mice are defective in inducing differentiation of these cell population.39     In addition to the generation of T-reg cells, the activation of HCA2/GPR109A in epithelial cells in the small intestine may induce the production of PGE2,15 which contributes to the anti-inflammatory response. PGE2 suppresses the production of proinflammatory cytokines and enhances the synthesis of anti-inflammatory cytokines.40 Therefore, PGE2 is not only a proinflammatory molecule but also a modulator of immune responses40. We hypothesize that DMF/MMF may amplify the anti-inflammatory response by binding to HCA2/GPR109A in gut cells (dendritic and epithelial), inducing the production of PGE2. Since DMF is metabolized in the gut, further studies are necessary to demonstrate whether the DMF/MMF stimulation of anti-inflammatory response in the gut may also contribute to the reduction of the tissue damage in the CNS of MS patients. 


Conclusions 
The complete mechanism of action of DMF in the treatment of MS remains to be elucidated. Recent observations highlight the importance of the activation of HCA2/GPR109A pathway by DMF/MMF in the downregulation of the immune response. Binding of DMF or MMF to HCA2/GPR109A on dendritic cells inhibits the production of pro-inflammatory cytokines in vitro and in EAE. There is a possibility that anti-inflammatory responses in intestinal mucosa are activated by DMF or MMF binding to HCA2/GPR109A, which is expressed on the surfaces of both immune cells and gut epithelial cells. Both forms can activate HCA2/GPR109A to differing extents, and therefore this possibility requires more study before an HCA2/GPR109A -mediated GI role for a specific form of fumarate can be determined. Given the extension of the gastrointestinal tract and the amount of cells expressing HCA2/GPR109A in intestinal mucosa, the immunomodulatory response in this compartment is relevant and may contribute to the reduction of tissue damage of CNS in patients with MS



MS (Multiple Sclerosis) Treatment

Most MS is the relapsing remitting kind.
Acute episodes are generally treated with steroids, which are inexpensive.

Some people’s autism is episodic; there is a base level and then there are periods when it becomes much more severe.
While there are no cures for MS there are disease modifying treatments that aim to reduces the frequency of the acute periods and reduce the damage that they cause. Since MS is essentially an auto-immune conditions, these treatments are all based on modifiying the immune system. They can have the side effect of overly reducing the immune response and then not fighting off a dangerous virus.

·        Interferons are used particularly to reduce the level of the proinflammatory cytokine IL-1beta.
·        Monoclonal antibodies are used to strengthen the blood brain barrier (and leaky gut barrier in Crohn’s) and so reduce the ability of inflammatory cytokines to enter the brain.
·        Classical immune-modulators include glatiramer acetate. Administration of glatiramer acetate shifts the population of T cells from proinflammatory Th1 T-cells to regulatory Th2 T-cells that suppress the inflammatory response. Dimethyl Fumarate was recently approved in the US and Europe as an MS drug in this category
In terms of potency and value, the UK’s review body was pretty upbeat about Dimethyl Fumarate.
All the disease modifying treatments for MS are hugely expensive, which must limit their use. 

ERβ
Interestingly, estrogen receptor beta (ERβ) is very relevant to MS, as we have seen it is to autism and also SATB2.  The most potent accessible agonist of ERβ is estrogen/estradiol, but unfortunately it also affects ERα. The ideal solution would be a brain specific selective agonist of ERβ. This does actually exist; it is called DHED, but it has not been commercialized. 
I think DHED would be helpful in MS, SATB2 and much idiopathic autism.
It is not surprising that MS mainly affects females and not surprisingly it gets worse post menopause. You would think someone would make the connection and treat this (with an ERβ agonist).


PDE4 inhibition

Another very logical therapy for MS is to use a PDE4 inhibitor to improve remyelination, this happens via activating PKA. PDE4 inhibition will also be broadly anti-inflammatory and this is why it is effective in asthma and COPD.

The good news is that the Japanese have been using a PDE4 inhibitor (Ibudilast)  for decades to treat asthma. So its safety profile is well known.

Not surprisingly under the new name MN-166, Ibudilast is showing promise.

               A Phase II Trial of Ibudilast in Progressive Multiple Sclerosis


In Western world Roflumilast (Daxas) is the widely used PDE4 inhibitor. It looks to me that the Japanese created a better drug - more selective and fewer side effects. In the long term MS trial of Ibudilast it was found that while GI side effects did occur at higher doses, they settled in 2-4 days; so no bid deal. Daxas does cause nausea, Ibudilast seems not to.

PDE4 inhibition is a very logical therapy choice for some autism and SATB2.

Relevance of MS to Autism
There are features of MS that are relevant to some autism, just like some MS features relate to Crohn’s. So, there is merit in understanding the current knowledge of MS treatment.
In terms of personalized medicine, we can see this broadens the potential toolkit to treat aberrant immune responses.
You can also see how someone with MS might benefit from reading autism science. They really should be making sure they produce enough butyric acid to   maintain tight epithelial barriers.  Butyrate not only causes a tightening of the intestinal epithelial barrier, but also the blood brain barrier. So if a leaky BBB is a feature of MS, then you want either to ferment butyric acid in your colon or a take sodium butyrate orally.

Budget MS Therapy
You can see that in a developing country, with no universal healthcare provision, a person could self-treat their own MS on a very modest budget. Tighten up the blood brain barrier, activate HCA2 and activate ERβ
In Chinese medicine there are treatments for postmenopausal osteoporosis, not surprisingly they are herbal ERβ agonists. The one recommended in a recent paper based on potency and safety was something called EXD (Er-Xian Decoction), more potent than Icariin as favoured by our reader Aspie1983.
Among the EXD, EBH, and ICA, EXD was found to have superior efficacy and safety profile.

Consuming soy will also activate ERβ, but you would need to eat it like a Japanese (lots of it).
Butter tea, as found in Tibet and nearby, would be rich in butyric acid and so should improve a leaky blood brain barrier.
I drank this very tea, made with Yak butter, decades ago and still recall the taste/smell.



I did stumble across one Australian psoriasis sufferer, who was self-treating with cheap non-medical DMF bought overseas. He seemed very happy with the result. If he develops MS he might just need to increase the dose.

Which HCA2 activator for some autism?
Well if you respond to BHB from ketone supplements it looks to me that HCA2 activation likely is involved, at least to some extent, particularly if your level of the cytokine IL-1β is normal. (If IL-1β is elevated, wait for part 4 of this series on ketones and autism.)
The simplest strategy would be to just up the BHB treatment.  The other options might include: -
·        Cinnamon

·        Niacin, which at high doses is used by some people with schizoprenia

·        Acipimox, a niacin derivative drug to lower cholesterol. 

·        DMF (Dimethyl fumarate) 
I have written about cinnamon before on this blog and I like the things it does, but if I was making a clinical trial I would go straight for the one that really should work, which is DMF. 
At high doses many people get side effects from DMF, but they usually fade over time.
Since BHB is not such a potent HCA2 activator, I doubt a large dose of DMF would be needed.

DMF as a drug        
Most readers of this blog are in North American, home of expensive drugs. Today you may be shocked at just how much is charged for DMF in the US.
In the form of Fumaderm, it available for free in some European countries.



Very recently a Spanish company has started to market DMF as a drug called Skilarence, so hopefully the price will eventually fall. 

DMF History and Cost
Dimethyl fumarate (DMF) is actually an inexpensive bulk chemical that is widely available.
Originally it was used in Germany to treat psoriasis.  Assuming a defect in the citrate cycle as the cause of his own psoriasis, Walter Schweckendiek, a German chemist, treated himself with large doses of succinic acid. When this first attempt was ineffective, he turned to the next metabolite in the cycle, fumaric acid, and experienced a ‘cure’ from his disease, as he reported in 1959.
To improve the gastrointestinal tolerance of fumaric acid he later used esters of fumaric acid. Although Schweckendiek published his own case report in a well-known German medical journal, his discovery first remained largely unrecognized by the academic medical community and spread mainly among alternative practitioners. This is how Hans-Peter Strobel, a Swiss village pharmacist, learned about the alleged efficacy of fumaric acid esters in 1982. 
One year later he founded the company Fumapharm AG, which further investigated fumaric acid esters leading to a Phase III study against psoriasis headed by Peter Altmeyer in 1994. This study earned fumaric acid esters the approval for treatment of psoriasis in Germany. Fumaderm, a preparation comprising mainly DMF, was on the German market for several years when neurologists in Germany recognized its efficacy against MS. In 2006 Biogen Idec bought Fumapharm and further developed DMF for the treatment of MS.
In the US Biogen sell Dimethyl Fumarate as Tecfidera, a single 240 mg tablet costs $120.
In Germany, the local company, also owned by Biogen of the US, still sells it as a treatment for psoriasis; a single tablet of Fumaderm 120mg for $4.
In China you can buy 100g for $6.
It looks like China is the place to be if you have MS. The Chinese just buys a bag of empty enteric capsules, measures out his DMF with his $10 micro scales.
Enteric capsules dissolve in the lower intestine where it is alkaline. Some drugs cannot survive in acidity earlier on in the digestive process.

His cost of 240g twice a day for a year

730 enteric capsules           $20

175g of DMF                     $10

Microscales                        $10

            Total                                 $40

His US counterpart (or his insurer) would pay $87,600 at the full price.
A German pharmacy would charge $5,840. The UK NHS will for sure have a discount on the German price and now they have switched to the Spanish version, Skilarence.
I think Walter Schweckendiek, the pioneering German chemist, who did all the original self-experimentation, would go for the “Chinese option” and treat himself for the annual cost of 3 Wiener Schnitzels.

HCA2/Gpr109a and colonic inflammation
We know that some people with autism have terrible GI inflammation; by activation HCA2 (also called Gpr109a) some people with colon inflammation may get some relief.
In the study below, they refer to the HCA2 activator butyric acid, but any HCA2 activator that end up in the colon should have the same effect.  To produce butyric acid, eat fiber and a butyric acid producing bacteria, as covered in earlier post. 


·         Commensal metabolite butyrate and niacin induce IL-18 in colon via Gpr109a
·         Butyrate and niacin induce IL-10 and Aldh1a in APCs in a Gpr109a-dependent manner
·         Niacr1 −/− mice exhibit increased risk for colitis and colon cancer 
·         Gpr109a signaling protects colon health during deficiency of gut bacteria and dietary fiber




It also is proposed that activating HCA2 in the gut has a positive effect in the brain for people with MS.  

Conclusion
HCA2 activation looks very interesting and I would love to know if this is a mechanism by which BHB/C8 supplements are improving autism for some readers of this blog.
It looks highly plausible. In one of the papers it was suggested that this is more likely than HDAC inhibition, because the effect of the ketone BHB on HCA2 is much larger than on HDAC 1, 3 or 4.
I am also interested that PPAR gamma is also activated via HCA2-PGD2 and then its metabolite 15d-PGJ, because the PPARγ agonists tangeretin/nobiletin in the supplement Sytrinol gives an improvement in autism for some people but for most, like my son, it only last 3 or 4 days.  The more potent PPARγ agonists used to treat Type 2 diabetes are reported in studies to improve some autism.
Cinnamon also seemed to have an effect in my trial, but there are several different substances in cinnamon that might be helping. I had not considered Cinnamic acid until this post.
People do use niacin for autism but based on the same level of science that made some people think that Multiple Sclerosis was caused by vitamin B3 deficiency (it is not).
The MS research raises the possibility that inflammation in the intestinal mucosa may be driving inflammation in the brain and that the effectiveness of HCA2 activation is in part driven by what is happening to the HCA2 receptors in your intestines rather than those in your brain.
I really do think some researcher should trial those little 30mg Fumaderm starter pills on people with autism. They use these lower dose pills before building up to the full psoriasis dose. The MS dose in the US is very much higher, 240mg twice a day.