Probiotics � Science and Pseudoscience


Once anyone starts to make claims that some autism is treatable, people respond in different ways.  Those applying what has always been taught in medical school, that autism is untreatable,  will either think you are making it all up, or worse, you are some evil person taking advantage of parents in emotional distress.

The very few people who read the research about things like metabolic errors and intracellular signaling may well take a different view. Also the oncology/cancer researchers who themselves think about sub-types of disease that are induced by specific signaling pathways (like RAS-induced cancers for example), may well see the sense in experimentation like that in this blog.

Medicine does indeed say that autism, Down Syndrome and ID/MR are untreatable; however current science does not support this.  Your local doctor applies medicine; he is likely totally out of his depth when it comes to where science is in 2016.

My posts are just my take on the science, I am well aware that some clever neurologists have looked at this blog and think it is all fantasy.  The doctors who have a child with autism and read this blog tend to look from a different perspective and with a much more open mind.  Once you find one therapy that is truly effective, bumetanide in our case, then there can be no turning back.

There are all kinds of diets, supplements and therapies promoted by various people, I wish them all well.

The problem any future science-based autism clinicians will have is that they inevitably get mixed up with other types.  In the US they already go to the same autism conferences, which surprises me. People then think, "Oh well if Professor X is here from Ivy League college Y, then everyone must be legit".  Big mistake. You need to be on really top form to separate out all the pseudoscience, and on occasion you may get it wrong. 


Probiotics

I used to be a skeptic of probiotic bacteria, that is until I was prescribed some little glass vials about a dozen years ago.  I had some side effect from an antibiotic prescribed for an ear infection.  I still recall the ENT doctor calling out (not in English) and asking what to prescribe for the GI side effects.  When I took his prescription to the pharmacy I received a pack of glass vials and a small saw blade.  You used the saw to cut the neck of the vial then you added water to the white fungus growing in the vial and poured into a glass of water, which you then drank.

It most definitely worked.

Even today when I tell my doctor relatives in the UK that probiotics work wonders for diarrhea, all I get is strange looks.

So I am already sold on the fact that probiotic bacteria can do great things for stomach problems.

I spoke to a friend in Denmark this week who has been ill much of the year and finally his problems have been diagnosed as stemming from Ulcerative Colitis.  His first symptom was actually a blood clot.  It turns out that inflammatory bowel diseases (IBD), like ulcerative colitis, increase your risk of blood clots.

So I told my friend to read up on VSL#3 and Viviomixx, which do seem to help IBD, and also to read up on melatonin in the IBD research.


Probiotics and Inflammatory Disease

Looking at immune health more generally we saw how the probiotic Miyairi 588 is used to produce butyric acid which can improve immune health.  This is why cost conscious farmers put it in their animal feed to produce healthier, faster growing animals.

We saw that an alternative is just to add sodium butyrate to the food.  This is done is both livestock and some humans.

Butyrate is an HDAC inhibitor and so is thought to have epigenetic effects.

Probiotics and the Brain

You might be able to convince your doctor that a probiotic bacterium can be good for your stomach, but would you convince him that it could be good for the brain?

I must admit I also would like to see some scientific evidence, beyond anecdotes - even my own anecdotes.

So finally today�s featured scientific study:-




 There is increasing, but largely indirect, evidence pointing to an effect of commensal gut microbiota on the central nervous system (CNS). However, it is unknown whether lactic acid bacteria such as Lactobacillus rhamnosus could have a direct effect on neurotransmitter receptors in the CNS in normal, healthy animals. GABA is the main CNS inhibitory neurotransmitter and is significantly involved in regulating many physiological and psychological processes. Alterations in central GABA receptor expression are implicated in the pathogenesis of anxiety and depression, which are highly comorbid with functional bowel disorders. In this work, we show that chronic treatment with L. rhamnosus (JB-1) induced region-dependent alterations in GABAB1b mRNA in the brain with increases in cortical regions (cingulate and prelimbic) and concomitant reductions in expression in the hippocampus, amygdala, and locus coeruleus, in comparison with control-fed mice. In addition, L. rhamnosus (JB-1) reduced GABAAa2 mRNA expression in the prefrontal cortex and amygdala, but increased GABAAa2 in the hippocampus. Importantly, L. rhamnosus (JB-1) reduced stress-induced corticosterone and anxiety- and depression-related behavior. Moreover, the neurochemical and behavioral effects were not found in vagotomized mice, identifying the vagus as a major modulatory constitutive communication pathway between the bacteria exposed to the gut and the brain. Together, these findings highlight the important role of bacteria in the bidirectional communication of the gut�brain axis and suggest that certain organisms may prove to be useful therapeutic adjuncts in stress-related disorders such as anxiety and depression.

The study is interesting because it shows that a bacterium can modify GABA subunit expression in the brain, but when the vagus nerve is removed the effect is lost.  So it is pretty likely that in humans the vagus nerve is the conduit to the brain, as has many times been suggested, but here we have some pretty conclusive supporting evidence.

For a less science heavy explanation of the study:-

Belly bacteria boss the brain

Gutmicrobes can change neurochemistry and influence behavior




I did a post about the vagus nerve a while back and there is an easy to read article here:-

Viva vagus: Wandering nerve could lead to range of therapies




My old posts:-

The Vagus Nerve and Autism


Cytokine Theory of Disease & the Vagus Nerve




Conclusion

Individual GI bacteria have very specific effects.  In people with neurological dysfunctions the possibility genuinely exists to delivery therapies to brain via the gut.  This might have been seen as pseudoscience a decade ago, but now it is part of science, but not yet medicine.

Many other clever things going on in your gut.  The long awaited CM-AT pancreatic enzyme therapy, from a company called Curemark, is now entering its phase 3 trial (thanks Natasa). Click below. 

Bl�m is the study of CM-AT, a biologic, for the treatment of Autism.



  
The Curemark lady, Joan Fallon, has collected numerous patents regarding various mixtures of pancreatic enzymes and even secretin.  Secretin was an autism therapy that was written off many years ago, but is still used by some DAN type doctors.

Some comments on this blog from parents of kids in the early CM-AT trials are supportive of its effect.

Pancreatic enzymes (e.g. Creon) are already used as a therapy for people who lack pancreatic enzymes and many people with autism have taken them.


Curemark have never published any of their trial data which annoys at least one of our medical researcher readers.  If you have so many patents, why not share your knowledge?






Excitotoxicity triggered by GABAa dysfunction




  
This blog, as you will have noticed, does rather meander through science of autism.  As a result there are some gaps and unanswered questions.

The blog talks a lot about the neurotransmitter GABA and the excitatory/inhibitory imbalance.  We have ended up with some therapies based on this that do seem to help many people.

The opposing (excitatory) neurotransmitter is glutamate which affects the NMDA, AMP and mGlu receptors.

It appears that in autism there is an unusually high level of glutamate, but another issue looks likely to be at specific receptors, for example mGluR5



This does get very complicated and lacks any immediate therapies. 

One very interesting insight was that you can repurpose the existing cheap generic GABAB drug Baclofen to treat NMDAR-hypofunction. 

This seems to work really well at low doses with many people with Asperger�s.  People with more severe autism do not seem to respond to low doses, however some do to higher doses.  The more potent version R Baclofen is a research drug.

GABAb-mediated rescue of altered excitatory�inhibitory balance, gamma synchrony and behavioral deficits following constitutive NMDAR-hypofunction



Reduced N-methyl-D-aspartate-receptor (NMDAR) signaling has been associated with schizophrenia, autism and intellectual disability. NMDAR-hypofunction is thought to contribute to social, cognitive and gamma (30�80?Hz) oscillatory abnormalities, phenotypes common to these disorders.

Constitutive NMDAR-hypofunction caused a loss of E/I balance, with an increase in intrinsic pyramidal cell excitability and a selective disruption of parvalbumin-expressing interneurons. Disrupted E/I coupling was associated with deficits in auditory-evoked gamma signal-to-noise ratio (SNR). Gamma-band abnormalities predicted deficits in spatial working memory and social preference, linking cellular changes in E/I signaling to target behaviors. The GABAB-receptor agonist baclofen improved E/I balance, gamma-SNR and broadly reversed behavioral deficits.



Excitotoxicity

We have touched on this subject on a few occasions but today, excitotoxicity is the focus of this post.
  
Excitotoxicity looks likely to be present in much autism and helps to connect all the various dysfunctions that we can read about in the literature.

It is a little scary because you cannot know to what extent this process is reversible.  It looks like in milder cases it should be treatable, whereas in extreme cases damage will be irreversible.

Excitotoxicity is the pathological process by which nerve cells are damaged or killed by excessive stimulation by neurotransmitters, particularly glutamate. This occurs when receptors for the excitatory neurotransmitter glutamate (glutamate receptors) such as the NMDA receptor and AMPA receptor are overactivated by glutamatergic storm. 

Unfortunately you can trigger glutamate excitotoxity via a dysfunction in GABAA receptors.

For example if you severely inhibit GABAA receptors you kill brain cells, but it was the reaction in glutamate signaling that did the damage.  GABA is supposed to be inhibitory; in some autism it is not and then Glutamate gets out of balance.  This does lead to excess firing of neurons, which seems to degrade cognition, but it will tend towards glutamate excitotoxity.

When you see the cascade of events triggered by glutamate excitotoxity you will see how this really helps to explain biological finding in autism, even mitochondrial dysfunctions.

You can then trace this all back to the faulty GABA switch caused by too little KCC2 and too much NKCC1.

Then you can look at other neurological conditions that feature glutamate excitotoxity, like traumatic brain injury and neuropathic pain, and you see that the research shows low expression of KCC2.

This then suggests that much of autism would have been prevented if you could increase KCC2.  You would not just fix the E/I imbalance but you would avoid all the damage done by excitotoxity.

Just how early you would have to correct KCC2 expression is not clear.  For sure it is a case of better late than never, but how much damage caused by excitotoxicity is reversible?


Good News

The good news is that because KCC2 underexpression is a feature of many conditions there is plenty of research money being spent looking for answers.  When they find a solution for increasing KCC2 to treat neuropathic pain, or spinal cord injury (SCI), the drug can be simply re-purposed for autism.

The French government is funding research into increasing KCC2 to treat SCI.  They are starting with serotin  5-HT2A receptor agonists.  Regular readers without any memory loss may recall that back in the 1960 Lovaas was giving LSD to people with autism at UCLA.  LSD is a potent 5-HT2A receptor agonist.  The French are also looking at BDNF to upregulate KCC2 and then they plan to have a blind test where they try all the chemicals they have in their library.  The French are of course doing their trials in test tubes.

When I looked at this subject a while back, I looked for existing therapies that are known to be safe and should be effective.

Treating KCC2 Down-Regulation in Autism, Rett/Down Syndromes, Epilepsy and Neuronal Trauma ?




My conclusion then was that intranasal insulin was the best choice.



Excitoxicity in Autism




Autism is a debilitating neurodevelopment disorder characterized by stereotyped interests and behaviours, and abnormalities in verbal and non-verbal communication. It is a multifactorial disorder resulting from interactions between genetic, environmental and immunological factors. Excitotoxicity and oxidative stress are potential mechanisms, which are likely to serve as a converging point to these risk factors. Substantial evidence suggests that excitotoxicity, oxidative stress and impaired mitochondrial function are the leading cause of neuronal dysfunction in autistic patients. Glutamate is the primary excitatory neurotransmitter produced in the CNS, and overactivity of glutamate and its receptors leads to excitotoxicity. The over excitatory action of glutamate, and the glutamatergic receptors NMDA and AMPA, leads to activation of enzymes that damage cellular structure, membrane permeability and electrochemical gradients. The role of excitotoxicity and the mechanism behind its action in autistic subjects is delineated in this review










The influx of intracellular calcium triggers the induction of inducible nitric oxide (iNOS) and phosphorylation of protein kinase C. Increased iNOS enhances nitric oxide (NO�) production in excess, whereas protein kinase C activates phospholipase A2 which in turn results in the generation of pro-inflammatory molecules The subsequent generation of free radicals can inhibit oxidative phosphorylation and damage mitochondrial enzymes involved in the electron transport chain, which mitigate energy production .

Reactive intermediates such as peroxynitrates and other peroxidation products hamper the normal function of mitochondrial enzymes by impairing oxidative phosphorylation and inhibiting complex II of the electron transport chain. Moreover, lipid peroxidation products, such as 4-hydroxynonenal (4-HNE) can interact with synaptic protein and impair transport of glucose and glutamate, thereby decreasing energy production and increasing excitotoxic sensitivity

Overstimulation of the glutamate receptors, NMDA and AMPA, leads to the release of other excitotoxins resulting in the accumulation of glutamate. Indeed, excess glutamate concentrations results in an increase in calcium levels in the cytosol. This effect is attributed to the fact that excessive glutamate allows calcium channel to open for longer periods of time, leading to increased influx of calcium into cells. Calcium triggers inducible nitric oxide and protein kinase C that produce free radicals, ROS and arachidonic aid. Generation of these oxidants results in mitochondrial dysfunction and accumulation of pro-inflammatory molecules and finally cell death. Free radicals interact with the mitochondrial and cellular membrane to form lipid peroxidation. 4-HNE is a major destructive product of this process. Lipid peroxidation prevents the dephosphorylation of excessively phosphorylated tau protein, significantly interfering with microtubule function. It has also been shown to inhibit glutathione reductase needed to convert oxidised glutathione to its functional reduced form

The mechanism responsible for excitotoxicity and neuronal cell death is diverse. Experimental studies have shown that the apoptotic and/or necrotic cell death may be due to the severity of NMDA damage or can be dependent on receptor subunit composition of neurons (Bonfoco et al. 1995; Portera-Cailliau et al. 1997). Pathological events related to this mode of action can be loss of cellular homoeostasis with acute mitochondrial dysfunction leading to hindrance in ATP production. Moreover, glutamatergic insults can cause cell death by the action of one or more molecular pathways which involves the action of signaling molecules such as cysteine proteases, mitochondrial endonucleases, peroxynitrite, PARP-1 and GAPDH in the excitotoxic neurodegeneration pathway.

Intracellular calcium levels also rely on voltage-dependent calcium channels and Na exchangers . The Na?/Ca2? exchanger is a bi-directional membrane ion transporter, which during membrane depolarisation or the opening of the gated sodium channels, transports sodium out of the cell and calcium into the cell. AMPA-type glutamate receptors are highly permeable to calcium and its over expression can lead to excitotoxicity. The Ca2? permeability capability of AMPA-type glutamate receptors relies on the presence or the absence of the GluR2 subunit in the receptor complex. Reduced GluR2 expression permits the construction of AMPA receptors with high Ca2? permeability and contributes to neuronal defect and excitotoxicity. Another mechanism is the release of calcium from internal stores such as the endoplasmic reticulum and mitochondria. It results in mitochondrial dysfunction, reduction in ATP synthesis and ROS generation.

Voltage gated channels found in dendrites and cell bodies of neurons modulate neuronal excitability and calcium-regulated signaling cascades (Dolmetsch et al. 2001; Catterall et al. 2005). Point mutations in the gene encoding the L-type voltage-gated channels Ca v1.2 (CACNA1C) and Ca v1.4. (CACNA1F) prevent voltage-dependent inactivation of these genes. This causes the channel to open for longer time, leading to excessive influx of calcium.

Conclusion

Autism is a multifactorial disorder characterized by neurobehavioral and neurological dysfunction. Excitotoxicity is the major neurobiological mechanism that modulates diverse risk factors associated with autism. It is triggered by potential mutation in ion channels and signalling pathways, viral and bacterial pathogens, toxic metals and free radical generation. Over expression of glutamate receptors and increased glutamate levels leads to increased calcium influx and oxidative stress and progressive cellular degeneration and cell death. Genetic defect, such as mutation in voltage gated or ligand channels that regulate neuronal excitability leads to defect in synaptic transmission and excitotoxic condition in autism. Mutation in BKCa and Ca v1.2 channels also results in excess calcium influx Sodium, potassium and chloride channels also play important roles in maintaining homoeostasis of neuronal cells, and decreased channel activity leads to destabilization of membrane potential and excitotoxicity. Moreover, over expression of BDNF results in hyperexcitability. Excessive BDNF and NMDA receptor activity increases the neurotransmitter release and excitotoxic vulnerability. Given that autism is a multifaceted disorder with multiple risk factors, more precise studies are needed to explore the signalling pathways that influence emergence of excitotoxicity in ASDs.


Some relevant reading for those interested:-


GABAergic/glutamatergic imbalance relative to excessive neuroinflammation in autism spectrum disorders


Abstract

Background

Autism spectrum disorder (ASD) is characterized by three core behavioral domains: social deficits, impaired communication, and repetitive behaviors. Glutamatergic/GABAergic imbalance has been found in various preclinical models of ASD. Additionally, autoimmunity immune dysfunction, and neuroinflammation are also considered as etiological mechanisms of this disorder. This study aimed to elucidate the relationship between glutamatergic/ GABAergic imbalance and neuroinflammation as two recently-discovered autism-related etiological mechanisms.

Methods

Twenty autistic patients aged 3 to 15 years and 19 age- and gender-matched healthy controls were included in this study. The plasma levels of glutamate, GABA and glutamate/GABA ratio as markers of excitotoxicity together with TNF-a, IL-6, IFN-? and IFI16 as markers of neuroinflammation were determined in both groups.

Results

Autistic patients exhibited glutamate excitotoxicity based on a much higher glutamate concentration in the autistic patients than in the control subjects. Unexpectedly higher GABA and lower glutamate/GABA levels were recorded in autistic patients compared to control subjects. TNF-a and IL-6 were significantly lower, whereas IFN-? and IFI16 were remarkably higher in the autistic patients than in the control subjects.

Conclusion

Multiple regression analysis revealed associations between reduced GABA level, neuroinflammation and glutamate excitotoxicity. This study indicates that autism is a developmental synaptic disorder showing imbalance in GABAergic and glutamatergic synapses as a consequence of neuroinflammation.
Keywords: Autism, Glutamate excitotoxicity, Gamma aminobutyric acid (GABA), Glutamate/GABA, Tumor necrosis factor-a, Interleukin-6, Interferon-gamma, Interferon-gamma-inducible protein 16


Postmortem brain abnormalities of the glutamate neurotransmitter system in autism.



CONCLUSIONS:

Subjects with autism may have specific abnormalities in the AMPA-type glutamate receptors and glutamate transporters in the cerebellum. These abnormalities may be directly involved in the pathogenesis of the disorder.



Pathophysiologyof traumatic brain injury


General pathophysiology of traumatic brain injury
The first stages of cerebral injury after TBI are characterized by direct tissue damage and impaired regulation of CBF and metabolism. This �ischaemia-like� pattern leads to accumulation of lactic acid due to anaerobic glycolysis, increased membrane permeability, and consecutive oedema formation. Since the anaerobic metabolism is inadequate to maintain cellular energy states, the ATP-stores deplete and failure of energy-dependent membrane ion pumps occurs. The second stage of the pathophysiological cascade is characterized by terminal membrane depolarization along with excessive release of excitatory neurotransmitters (i.e. glutamate, aspartate), activation of N-methyl-d-aspartate, a-amino-3-hydroxy-5-methyl-4-isoxazolpropionate, and voltage-dependent Ca2+- and Na+-channels. The consecutive Ca2+- and Na+-influx leads to self-digesting (catabolic) intracellular processes. Ca2+ activates lipid peroxidases, proteases, and phospholipases which in turn increase the intracellular concentration of free fatty acids and free radicals. Additionally, activation of caspases (ICE-like proteins), translocases, and endonucleases initiates progressive structural changes of biological membranes and the nucleosomal DNA (DNA fragmentation and inhibition of DNA repair). Together, these events lead to membrane degradation of vascular and cellular structures and ultimately necrotic or programmed cell death (apoptosis).

Excitotoxicity and oxidative stress
TBI is primarily and secondarily associated with a massive release of excitatory amino acid neurotransmitters, particularly glutamate.854 This excess in extracellular glutamate availability affects neurons and astrocytes and results in over-stimulation of ionotropic and metabotropic glutamate receptors with consecutive Ca2+, Na+, and K+-fluxes.2273 Although these events trigger catabolic processes including blood�brain barrier breakdown, the cellular attempt to compensate for ionic gradients increases Na+/K+-ATPase activity and in turn metabolic demand, creating a vicious circle of flow�metabolism uncoupling to the cell.1650
Oxidative stress relates to the generation of reactive oxygen species (oxygen free radicals and associated entities including superoxides, hydrogen peroxide, nitric oxide, and peroxinitrite) in response to TBI. The excessive production of reactive oxygen species due to excitotoxicity and exhaustion of the endogenous antioxidant system (e.g. superoxide dismutase, glutathione peroxidase, and catalase) induces peroxidation of cellular and vascular structures, protein oxidation, cleavage of DNA, and inhibition of the mitochondrial electron transport chain.31160 Although these mechanisms are adequate to contribute to immediate cell death, inflammatory processes and early or late apoptotic programmes are induced by oxidative stress.11



Knocking down of the KCC2 in rat hippocampal neurons increases intracellular chloride concentration and compromises neuronal survival



Non-technical summary

�To be, or not to be�� thousands of neurons are facing this Shakespearean question in the brains of patients suffering from epilepsy or the consequences of a brain traumatism or stroke. The destiny of neurons in damaged brain depends on tiny equilibrium between pro-survival and pro-death signalling. Numerous studies have shown that the activity of the neuronal potassium chloride co-transporter KCC2 strongly decreases during a pathology. However, it remained unclear whether the change of the KCC2 function protects neurons or contributes to neuronal death. Here, using cultures of hippocampal neurons, we show that experimental silencing of endogenous KCC2 using an RNA interference approach or a dominant negative mutant reduces neuronal resistance to toxic insults. In contrast, the artificial gain of KCC2 function in the same neurons protects them from death. This finding highlights KCC2 as a molecule that plays a critical role in the destiny of neurons under toxic conditions and opens new avenues for the development of neuroprotective therapy.


New understanding of brainchemistry could prevent brain damage after injury





Sciences de la vie, de la sant� et des �cosyst�mes : Neurosciences (Blanc SVSE 4) 2010
Projet 
KCC2-SCI

The potassium-chloride transporter KCC2 : a new target for the treatment of neurological diseases




A decrease in synaptic inhibition �disinhibition- appears to be an important substrate in several neuronal disorders, such as spinal cord injury (SCI), neuropathic pain... Glycine and GABA are the major inhibitory transmitters in the spinal cord. An important emerging mechanism by which the strength of inhibitory synaptic transmission can be controlled is via modification of the intracellular concentration of chloride ions ([Cl-]i) to which receptors to GABA/glycine are permeable. Briefly, a low [Cl-]i is a pre-requisite for inhibition to occur and is maintained in healthy neurons by cation-chloride co-transporters (KCC2) in the plasma membrane, which extrude Cl-. We showed recently (Nature Medicine, accepted for publication) that these transporters are down-regulated after SCI, thereby switching the action of GABA and glycine from inhibition to excitation; this can account for both SCI-induced spasticity and chronic pain. KCC2 transporters therefore appear as a new target to restore inhibition within neuronal networks in pathological conditions. The present project aims at reducing spasticity and chronic pain after SCI by up-regulating KCC2. 
An important part will consist in identifying new compounds that increase the cell surface expression and/or the functionality of KCC2. Two strategies are considered. 1) Serotonin and BDNF will be tested on the basis of preliminary experiments and/or previous reports in other areas of the central nervous system indicating that these two compounds may affect the expression of KCC2. 2)Testing a large amount of compounds available in a library (�blind test�) to sort out KCC2-modulating molecules. This task can only be done in vitro on an assay that enables to easily visualize and quantify cell surface expression of KCC2, in response to these molecules (HEK293 cells). The few compounds isolated at the end of this task will then be tested on cultures of motoneurons (both mouse motoneurons and human motoneurons derived from induced pluripotent cells) and characterized further (potential toxicity, ability to cross the Brain Blood Barrier and effect on internalization and endocytosis of KCC2). 
The selected candidate compounds will enter into the in vivo validation phase aimed at increasing the expression of KCC2 following spinal cord injury (SCI; both contusion and complete spinal cord transection). The selected hits will be applied by intrathecal injections in SCI rats and their effects on KCC2 expression in the plasma membrane of motoneurons will be tested by means of western blots and immunohistochemistry. Their efficacy in increasing the cell-surface expression of KCC2 will also be tested electrophysiologically in vitro (i.e. their ability to hyperpolarize ECl). Functionally, their efficacy in reducing both SCI-induced spasticity and chronic pain will be assessed. 
Genetic tools will be used to increase the expression of KCC2 in some spinal neurons. This task will be done in collaboration with teams in the USA. Lentiviral vectors aimed at increasing KCC2 in the host cells, after parenchymal injection, have been developed in San Diego. A transgenic mouse model with a conditional tamoxifen-induced overexpression of KCC2 has been developed in Pittsburgh. The rationale for this part of the project is to use these genetic tools in the chronic phase of SCI to reduce spasticity and chronic pain. 
The last part of the project will focus on more fundamental issues regarding the relationship between the SCI-induced downregulation of KCC2 and the development of spasticity and chronic pain. 
The significance of the expected results goes far beyond the scope of SCI, since altered chloride homeostasis resulting from mutation or dysfunction of cation-chloride cotransporters has been implicated in various neurological disorders such as, for instance, ischemic seizures neonatal seizures and temporal lobe epilepsy. 


KCC2 escape from neuropathic pain






Activationof 5-HT2A receptors upregulates the function of the neuronal K-Cl cotransporter KCC2.



 In healthy adults, activation of γ-aminobutyric acid (GABA)(A) and glycine receptors inhibits neurons as a result of low intracellular chloride concentration ([Cl(-)](i)), which is maintained by the potassium-chloride cotransporter KCC2. A reduction of KCC2 expression or function is implicated in the pathogenesis of several neurological disorders, including spasticity and chronic pain following spinal cord injury (SCI). Given the critical role of KCC2 in regulating the strength and robustness of inhibition, identifying tools that may increase KCC2 function and, hence, restore endogenous inhibition in pathological conditions is of particular importance. We show that activation of 5-hydroxytryptamine (5-HT) type 2A receptors to serotonin hyperpolarizes the reversal potential of inhibitory postsynaptic potentials (IPSPs), E(IPSP), in spinal motoneurons, increases the cell membrane expression of KCC2 and both restores endogenous inhibition and reduces spasticity after SCI in rats. Up-regulation of KCC2 function by targeting 5-HT(2A) receptors, therefore, has therapeutic potential in the treatment of neurological disorders involving altered chloride homeostasis. However, these receptors have been implicated in several psychiatric disorders, and their effects on pain processing are controversial, highlighting the need to further investigate the potential systemic effects of specific 5-HT(2A)R agonists, such as (4-bromo-3,6-dimethoxybenzocyclobuten-1-yl)methylamine hydrobromide (TCB-2).



Conclusion

Very little is certain in autism, in great part because only about 200 brains have ever been examined post mortem.  There are many theories, but very many more sub-types of autism.

GABAA dysfunction due to the faulty GABA switch never increasing KCC2 expression in the first weeks of life, triggering glutamate excitotoxicity and all that follows would go a long way to explaining my son�s type of autism. It might well explain 30+% of all autism.

Clearly other causes of excess glutamate would lead to a similar result.







More on Treatable ID Masquerading as Autism



I did write a post a while back highlighting an excellent on line resource that gives clinicians data on 81 treatable forms of Intellectual Disability, ID (formerly known as mental retardation, MR).





There is a big overlap between the causes of some ID and causes of some autism.

If you have a case of autism, it is worth reviewing the 81 treatable forms of ID, just in case you have one, even a mild version causing minimal ID.  Partial dysfunctions certainly are possible, as we saw with biotin. 

It is also very interesting to look through the therapies used and see how they overlap with those used by people in their n=1 case of autism.

For example the therapy for SLOS (Smith�Lemli�Opitz syndrome) which is related to very low cholesterol is to give cholesterol and Simvastatin.  Simvastatin is widely used in older people to LOWER cholesterol.  Statins have several other known modes of action. We use Atorvastatin.

Note all the vitamin related syndromes etc.

The data is all on the online resource that is highlighted at the top of every page in this blog, but as one regular reader from Hong Kong pointed out, it is better to actually read it in table form.  

He recommended the two papers below.  I reproduced some of the tables, but I suggest you click the link to read the papers. 

The formatting is not so good, since I have cut and paste from the papers.

You have the syndromes, their therapies and their diagnostic tests.

Complicated questions should be addressed to the authors of the papers or your doctor.







Table 2Overview of all 81 treatable IDs.In this table, the IEMs are grouped according to the biochemical phenotype as presented in standard textbooks, and alphabetically. Of note, primary CoQ deficiency was considered as one single IEM even though more though 6 genes have been described; this is true as well for MELAS and Pyruvate Dehydrogenase Complex deficiency.
Biochemical category
Disease name
OMIM#
Biochemical deficiency
Gene(s)
Amino acids
HHH syndrome (hyperornithinemia, hyperammonemia, homocitrullinemia)
238970
Ornithine translocase
SLC25A15 (AR)
l.o. Non-ketotic hyperglycinemia
605899
Aminomethyltransferase/glycine decarboxylase/glycine cleavage system H protein
AMT/GLDC/GCSH (AR)
Phenylketonuria
261600
Phenylalanine hydroxylase
PAH (AR)
PHGDH deficiency(Serine deficiency)
601815
Phosphoglycerate dehydrogenase
PHGDH (AR)
PSAT deficiency(Serine deficiency)
610992
Phosphoserine aminotransferase
PSAT1 (AR)
PSPH deficiency(Serine deficiency)
614023
Phosphoserine phosphatase
PSPH (AR)
Tyrosinemia type II
276600
Cytosolic tyrosine aminotransferase
TAT (AR)
Cholesterol & bile acids
Cerebrotendinous xanthomatosis
213700
Sterol-27-hydroxylase
CYP27A1 (AR)
Smith�Lemli�Opitz Syndrome
270400
7-Dehydroxycholesterol reductase
DHCR7 (AR)
Creatine
AGAT deficiency
612718
Arginine: glycine amidinotransferase
GATM (AR)
Creatine transporter Defect
300352
Creatine transporter
SLC6A8 (X-linked)
GAMT deficiency
612736
Guanidino-acetate-N-methyltransferase
GAMT (AR)
Fatty aldehydes
Sj�gren�Larsson syndrome
270200
Fatty aldehyde dehydrogenase
ALDH3A2 (AR)
Glucose transport & regulation
GLUT1 deficiency syndrome
606777
Glucose transporter blood�brain barrier
SLC2A1 (AR)
Hyperinsulinism hyperammonemia syndrome
606762
Glutamate dehydrogenase superactivity
GLUD1 (AR)
Hyperhomocysteinemia
Cobalamin C deficiency
277400
Methylmalonyl-CoA mutase and homocysteine : methyltetrahydrofolate methyltransferase
MMACHC (AR)
Cobalamin D deficiency
277410
C2ORF25 protein
MMADHC (AR)
Cobalamin E deficiency
236270
Methionine synthase reductase
MTRR (AR)
Cobalamin F deficiency
277380
Lysosomal cobalamin exporter
LMBRD1 (AR)
Cobalamin G deficiency
250940
5-Methyltetrahydrofolate-homocysteine S-methyltransferase
MTR (AR)
Homocystinuria
236200
Cystathatione �-synthase
CBS (AR)
l.o. MTHFR deficiency
236250
Methylenetetrahydrofolate reductase deficiency
MTHFR (AR)
Lysosomes
a-Mannosidosis
248500
a-Mannosidase
MAN2B1 (AR)
Aspartylglucosaminuria
208400
Aspartylglucosaminidase
AGA (AR)
Gaucher disease type III
231000
�-Glucosidase
GBA (AR)
Hunter syndrome (MPS II)
309900
Iduronate-2-sulfatase
IDS (X-linked)
Hurler syndrome (MPS I)
607014
a-L-iduronidase
IDUA (AR)
l.o. Metachromatic leukodystrophy
250100
Arylsulfatase A
ARSA (AR)
Niemann�Pick disease type C
257220
Intracellular transport cholesterol & sphingosines
NPC1 NPC2 (AR)
Sanfilippo syndrome A (MPS IIIa)
252900
Heparan-N-sulfatase
SGSH (AR)
Sanfilippo syndrome B (MPS IIIb)
252920
N-acetyl-glucosaminidase
NAGLU (AR)
Sanfilippo syndrome C (MPS IIIc)
252930
Acetyl-CoA glucosamine-N-acetyl transferase
HGSNAT (AR)
Sanfilippo syndrome D (MPS IIId)
252940
N-acetyl-glucosamine-6-Sulfatase
GNS (AR)
Sly syndrome (MPS VII)
253220
�-glucuronidase
GUSB (AR)
Metals
Aceruloplasminemia
604290
Ceruloplasmin (iron homeostasis)
CP (AR)
Menkes disease/Occipital horn syndrome
304150
Copper transport protein (efflux from cell)
ATP7A (AR)
Wilson disease
277900
Copper transport protein (liver to bile)
ATP7B (AR)
Mitochondria
Co enzyme Q10 deficiency
607426
Coenzyme Q2 or mitochondrial parahydroxybenzoate-polyprenyltransferase; aprataxin; prenyl diphosphate synthase subunit 1; prenyl diphosphate synthase subunit 2; coenzyme Q8; coenzyme Q9
COQ2, APTX, PDSS1, PDSS2, CABC1, COQ9 (most AR)
MELAS
540000
Mitochondrial energy deficiency
MTTL1MTTQ,MTTHMTTK,MTTCMTTS1,MTND1MTND5,MTND6MTTS2 (Mt)
PDH complex deficiency
OMIM# according to each enzyme subunit deficiency: 312170; 245348; 245349
Pyruvate dehydrogenase complex (E1a, E2, E3)
PDHA1 (X-linked), DLAT (AR), PDHX (AR)
Neurotransmission
DHPR deficiency (biopterin deficiency)
261630
Dihydropteridine reductase
QDPR (AR)
GTPCH1 deficiency (biopterin deficiency)
233910
GTP cyclohydrolase
GCH1 (AR)
PCD deficiency (biopterin deficiency)
264070
Pterin-4a-carbinolamine dehydratase
PCBD1 (AR)
PTPS deficiency (biopterin deficiency)
261640
6-Pyruvoyltetrahydropterin synthase
PTS (AR)
SPR deficiency (biopterin deficiency)
612716
Sepiapterin reductase
SPR (AR)
SSADH deficiency
271980
Succinic semialdehyde dehydrogenase
ALDH5A1 (AR)
Tyrosine Hydroxylase Deficiency
605407
Tyrosine Hydroxylase
TH (AR)
Organic acids
3-Methylcrotonyl glycinuria
GENE OMIM # 210200; 210210
3-Methylcrotonyl CoA carboxylase (3-MCC)
MCC1/MCC2 (AR)
3-Methylglutaconic aciduria type I
250950
3-Methylglutaconyl-CoA hydratase
AUH (AR)
�-Ketothiolase deficiency
203750
Mitochondrial acetoacetyl-CoA thiolase
ACAT1 (AR)
Cobalamin A deficiency
251100
MMAA protein
MMAA (AR)
Cobalamin B deficiency
251110
Cob(I)alamin adenosyltransferase
MMAB (AR)
Ethylmalonic encephalopathy
602473
Mitochondrial sulfur dioxygenase
ETHE1 (AR)
l.o. Glutaric acidemia I
231670
Glutaryl-CoA dehydrogenase
GCDH (AR)
Glutaric acidemia II
231680
Multiple acyl-CoA dehydrogenase
ETFAETFB,ETFDH (AR)
HMG-CoA lyase deficiency
246450
3-Hydroxy-3-methylglutaryl-CoA lyase
HMGCL (AR)
l.o. Isovaleric acidemia
243500
Isovaleryl-CoA dehydrogenase
IVD (AR)
Maple syrup urine disease (variant)
248600
Branched-chain 2-ketoacid complex
BCKDHA/BCKDHB/ DBT (AR)
l.o. Methylmalonic acidemia
251000
Methylmalonyl-CoA mutase
MUT (AR)
MHBD deficiency
300438
2-Methyl-3-hydroxybutyryl-CoA dehydrogenase
HSD17B10 (X-linked recessive)
mHMG-CoA synthase deficiency
605911
Mitochondrial 3-hydroxy-3-Methylglutaryl-CoA synthase
HMGCS2 (AR)
l.o. Propionic acidemia
606054
Propionyl-CoA carboxylase
PCCA/PCCB (AR)
SCOT deficiency
245050
Succinyl-CoA 3-oxoacid CoA transferase
OXCT1 (AR)
Peroxisomes
X-linked adrenoleukodystrophy
300100
Peroxisomal transport membrane protein ALDP
ABCD1 (X-linked)
Pyrimidines
Pyrimidine 5-nucleotidase superactivity
GENE OMIM # 606224
Pyrimidine-5-nucleotidase Superactivity
NT5C3 (AR)
Urea cycle
l.o. Argininemia
207800
Arginase
ARG1 (AR)
l.o. Argininosuccinic aciduria
207900
Argininosuccinate lyase
ASL (AR)
l.o. Citrullinemia
215700
Argininosuccinate Synthetase
ASS1 (AR)
Citrullinemia type II
605814
Citrin (aspartate�glutamate carrier)
SLC25A13
l.o. CPS deficiency
237300
Carbamoyl phosphate synthetase
CPS1 (AR)
l.o. NAGS deficiency
237310
N-acetylglutamate synthetase
NAGS (AR)
l.o. OTC Deficiency
311250
Ornithine transcarbamoylase
OTC (X-linked)
Vitamins/co-factors
Biotinidase deficiency
253260
Biotinidase
BTD (AR)
Biotin responsive basal ganglia disease
607483
Biotin transport
SLC19A3(AR)
Cerebral folate receptor-a deficiency
613068
a.o. Cerebral folate transporter
FOLR1 (AR)
Congenital intrinsic factor deficiency
261000
Intrinsic factor deficiency
GIF (AR)
Holocarboxylase synthetase deficiency
253270
Holocarboxylase synthetase
HLCS (AR)
Imerslund Gr�sbeck syndrome
261100
IF-Cbl receptor defects (cubulin/amnionless)
CUBN & AMN (AR)
Molybdenum co-factor deficiency type A
252150
Sulfite oxidase & xanthine dehydrogenase & aldehyde oxidase
MOCS1MOCS2,(AR)
Pyridoxine dependent epilepsy
266100
Pyridoxine phosphate oxidase
ALDH7A1 (AR),
Thiamine responsive encephalopathy
606152
Thiamine transport
SLC19A3 (AR)


Table 5Overview of all causal therapies (n=91).This Table provides an overview of the specific therapy/-ies available for each IEM with relevant level(s) of evidence, therapeutic effect(s) on primary and/or secondary outcomes and use in clinical practice. For 10 IEMs, two therapies are available; these are listed separately (in brackets).
Disease name
Therapeutic modality (-ies)
Level of evidence
Clinical practice
Treatment effect
Literature references
Aceruloplasminemia
Iron chelation
4
Standard of care
D,E
(X-linked)adrenoleukodystrophy
Stemcell transplantation (Gene therapy)
1c (5)
Individual basis (Individual basis)
D,E (D,E)
AGAT deficiency
Creatine supplements
4
Standard of care
A,D
a-Mannosidosis
Haematopoietic stem cell transplantation
4-5
Individual basis
D
l.o. Argininemia
Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation)
2b (4)
Standard of care (Individual basis)
B,C,D,E,F,G (C)
l.o. Argininosuccinic aciduria
Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (liver transplantation)
2b (4)
Standard of care (individual basis)
B,C,D,E,F,G (C)
Aspartylglucosaminuria
Haematopoietic stem cell transplantation
4-5
Individual basis
D
�-Ketothiolase deficiency
Avoid fasting, sickday management, protein restriction
5
Standard of care
C
Biotin responsive basal ganglia disease
Biotin supplement
4
Standard of care
A,E
Biotinidase deficiency
Biotin supplement
2c
Standard of care
A,E,G
Cerebral folate receptor-a deficiency
Folinic acid
4
Standard of care
A,D,E,F
Cerebrotendinous xanthomatosis
Chenodesoxycholic acid, HMG reductase inhibitor
4
Standard of care
B,D,E,G
l.o. Citrullinemia
Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation)
2b (4)
Standard of care (Individual basis)
B,C,D,E,F,G (C)
Citrullinemia type II
Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation)
2b (4)
Standard of care (Individual basis)
B,C,D,E,F,G (C)
Co enzyme Q10 deficiency
CoQ supplements
4
Standard of care
E,F
Cobalamin A deficiency
Hydroxycobalamin, protein restriction
4
Standard of care
C,G
Cobalamin B deficiency
Hydroxycobalamin, protein restriction
4
Standard of care
C,G
Cobalamin C deficiency
Hydroxycobalamin
4
Standard of care
C,D,G
Cobalamin D deficiency
Hydroxy-/cyanocobalamin
4
Standard of care
C,D,G
Cobalamin E deficiency
Hydroxy-/methylcobalamin, betaine
4
Standard of care
C,D,G
Cobalamin F deficiency
Hydroxycobalamin
4
Standard of care
C,D,G
Cobalamin G deficiency
Hydroxy-/methylcobalamin, betaine
4
Standard of care
C,D,G
Congenital intrinsic factor deficiency
Hydroxycobalamin
4
Standard of care
A,E,G
l.o. CPS deficiency
Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation)
2b & 4
Standard of care (Individual basis)
B,C,D,E,F,G (C)
Creatine transporter defect
Creatine, glycine, arginine supplements
4-5
Individual basis
F
DHPR deficiency
BH4,diet, amine replacement, folinic acid
4
Standard of care
A,E
Ethylmalonic encephalopathy
N-acetylcysteine, oral metronidazol
4
Standard of care
E,G
GAMT deficiency
Arginine restriction, creatine & ornithine supplements
4
Standard of care
B,D,E,F
Gaucher disease type III
Haematopoietic stem cell transplantation
4�5
Individual basis
D,G
GLUT1 deficiency syndrome
Ketogenic diet
4
Standard of Care
F
l.o. Glutaric acidemia I
Lysine restriction, carnitine supplements
2c
Standard of care
C,D,E,G
Glutaric acidemia II
Carnitine, riboflavin, �-hydroxybutyrate supplements; sick day management
5
Standard of care
C,G
GTPCH1 deficiency
BH4, amine replacement
4
Standard of care
A,E
HHH syndrome
Dietary protein restriction, ornithine supplement, sodium benzoate, phenylacetate
4
Standard of care
B,C,D,E,F,G
HMG-CoA lyase deficiency
Protein restriction, avoid fasting, sick day management,
5
Standard of care
C
Holocarboxylase synthetase deficiency
Biotin supplement
4
Standard of care
A,E,G
Homocystinuria
Methionine restriction, +/-pyridoxine, +/-betaine
2c
Standard of care
C,D,G
Hunter syndrome (MPS II)
Haematopoietic stem cell transplantation
4�5
Individual basis
D,G
Hurler syndrome (MPS I)
Haematopoietic stem cell transplantation
1c
Standard of care
D,G
Hyperammonemia�Hyperinsulinism syndrome
Diazoxide
4�5
Standard of care
D
Imerslund Gr�sbeck syndrome
Hydroxycobalamin
4
Standard of Care
A,E,G
l.o. Isovaleric acidemia
Dietary protein restriction, carnitine supplements, avoid fasting, sick day management
2c
Standard of care
C,G
l.o. NAGS deficiency
Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation)
2b & 4
Standard of care (Individual basis)
B,C,D,E,F,G (C)
l.o. Non-ketotic hyperglycinemia
Glycine restriction; +/-sodium benzoate, NMDA receptor antagonists, other neuromodulating agents
4-5
Standard of Care
B,D,E,F
Maple syrup urine disease (variant)
Dietary restriction branched amino-acids, avoid fasting, (Liver transplantation)
4 & 4
Standard of care (Individual basis)
B,C,D (A,C)
MELAS
Arginine supplements
4�5
Standard of Care
C,D,E,F
Menkes disease occipital horn syndrome
Copper histidine
4
Individual basis
D
l.o. Metachromatic leukodystrophy
Haematopoietic stem cell transplantation
4-5
Individual basis
D
3-Methylcrotonyl glycinuria
Dietary protein restriction; carnitine, glycine, biotin supplements; avoid fasting; sick day management
5
Standard of care
C
3-Methylglutaconic aciduria type I
Carnitine Supplements, Avoid Fasting, Sick Day Management
5
Standard of care
C
l.o. Methylmalonic acidemia
Dietary protein restriction, carnitine supplements, avoid fasting, sick day management
2c
Standard of care
C,G
MHBD deficiency
Avoid fasting, sick day management, isoleucine restricted diet
5
Standard of care
C
mHMG-CoA synthase deficiency
Avoid fasting,sick day management, +/-dietary precursor restriction
5
Standard of care
C
Molybdenum co-factor deficiency type A
Precursor Z/cPMP
4
Individual basis
A,F
l.o. MTHFR deficiency
Betaine supplements, +/-folate, carnitine, methionine supplements
4
Standard of care
C,D,G
Niemann�Pick disease type C
Miglustat
1b
Standard of care
D,E
l.o. OTC deficiency
Dietary protein restriction, citrulline supplements, Sodium benzoate/phenylbutyrate (Liver transplantation)
2b & 4
Standard of care (Individual basis)
B,C,D,E,F,G (C)
PCD deficiency
BH4
4
Standard of care
A,E
PDH complex deficiency
Ketogenic diet & thiamine
4
Individual basis
D,E,F
Phenylketonuria
Dietary phenylalanine restriction +/-amino-acid supplements (BH(4) supplement)
2a (4)
Standard of care (Individual basis)
B, D, E (C)
PHGDH deficiency
L-serine & +/-glycine supplements
4
Standard of care
D,F
PSAT deficiency
L-serine & +/-glycine supplements
4
Standard of care
D,F
l.o. Propionic acidemia
Dietary protein restriction, carnitine supplements, avoid fasting, sick day management
2c
Standard of care
C,G
PSPH deficiency
L-serine & +/-glycine supplements
4
Standard of care
D,F
PTPS deficiency
BH4, diet, amine replacement
4
Standard of care
A,E
Pyridoxine dependent epilepsy
Pyridoxine
4
Standard of care
A,F
Pyrimidine 5-nucleotidase superactivity
Uridine supplements
1b
Standard of care
A,B,F,G
Sanfilippo syndrome A (MPS IIIa)
Haematopoietic stem cell transplantation
4�5
Individual basis
D
Sanfilippo syndrome B (MPS IIIb)
Haematopoietic stem cell transplantation
4�5
Individual basis
D
Sanfilippo syndrome C (MPS IIIc)
Haematopoietic Stemcell Transplantation
4�5
Individual Basis
D
Sanfilippo syndrome D (MPS IIId)
Haematopoietic stem cell transplantation
4�5
Individual basis
D
SCOT deficiency
Avoid fasting, protein restriction, sick day management
5
Standard of care
C
Sj�gren�Larsson syndrome
Diet: low fat, medium chain & essential fatty acid supplements & Zileuton
5
Individual basis
D,G
Sly syndrome (MPS VII)
Haematopoietic stem cell transplantation
4-5
Individual basis
D
Smith�Lemli�Opitz syndrome
Cholesterol & simvastatin
4�5
Individual basis
B,D
SPR deficiency
Amine replacement
4
Standard of care
A,E
SSADH deficiency
Vigabatrin
4
Individual basis
B,F
Thiamine-responsive encephalopathy
Thiamin supplement
4-5
Standard of care
E
Tyrosine hydroxylase deficiency
L-dopa substitution
4
Standard of care
A,E
Tyrosinemia type II
Dietary phenylalanine & tyrosine restriction
4-5
Standard of care
D,G
Wilson disease
Zinc & tetrathiomolybdate
1b
Standard of care
E,G









Table 2aOverview of the first tier metabolic screening tests denoting all diseases (with OMIM# and gene(s)) potentially identified per individual test.
Diagnostic test
Disease
OMIM#
Gene
Blood tests
Plasma amino acids
l.o. Argininemia
ARG1 (AR)
Plasma amino acids
l.o. Argininosuccinic aciduria
ASL (AR)
Plasma amino acids
l.o. Citrullinemia
ASS1 (AR)
Plasma amino acids
Citrullinemia type II
SLC25A13 (AR)
Plasma amino acids
l.o. CPS deficiency
CPS1 (AR)
Plasma amino acids
HHH syndrome (hyperornithinemia, hyperammonemia, homocitrullinuria)
SLC25A15 (AR)
Plasma amino acids
Maple syrup urine disease (variant)
BCKDHA/BCKDHB/DBT(AR)
Plasma amino acids
l.o. NAGS deficiency
NAGS (AR)
Plasma amino acids (& UOA incl orotic acid)
l.o. OTC deficiency
OTC (X-linked)
Plasma amino acids
Phenylketonuria
PAH (AR)
Plasma amino acids (& UOA)
Tyrosinemia type II
TAT (AR)
Plasma amino acids (tHcy)
l.o. MTHFR deficiency
MTHFR (AR)
Plasma total homocysteine
Cobalamin E deficiency
MTRR (AR)
Plasma total homocysteine
Cobalamin G deficiency
MTR (AR)
Plasma total homocysteine (& UOA)
Cobalamin F deficiency
LMBRD1 (AR)
Plasma total homocysteine (& OUA)
Cobalamin C deficiency
MMACHC (AR)
Plasma total homocysteine (& OUA)
Homocystinuria
CBS (AR)
Plasma total homocysteine (& PAA)
l.o. MTHFR deficiency
MTHFR (AR)
Plasma total homocysteine (& UOA)
Cobalamin D deficiency
MMADHC (AR)
Serum ceruloplasmin & copper (& serum iron & ferritin)
Aceruloplasminemia
CP (AR)
Serum copper & ceruloplasmin (& urine copper)
MEDNIK diseases
AP1S1 (AR)
Serum copper & ceruloplasmin (urine deoxypyridonoline)
Menkes disease/occipital horn syndrome
ATP7A (AR)
Serum copper & ceruloplasmin (& urine copper)
Wilson disease
ATP7B (AR)
Urine tests
Urine creatine metabolites
AGAT deficiency
GATM (AR)
Urine creatine metabolites
Creatine transporter defect
SLC6A8 (X-linked)
Urine creatine metabolites
GAMT deficiency
GAMT (AR)
Urine glycosaminoglycans
Hunter syndrome (MPS II)
IDS (X-linked)
Urine glycosaminoglycans
Hurler syndrome (MPS I)
IDUA (AR)
Urine glycosaminoglycans
Sanfilippo syndrome A (MPS IIIa)
SGSH (AR)
Urine glycosaminoglycans
Sanfilippo syndrome B (MPS IIIb)
NAGLU (AR)
Urine glycosaminoglycans
Sanfilippo syndrome C (MPS IIIc)
HGSNAT (AR)
Urine glycosaminoglycans
Sanfilippo syndrome D (MPS IIId)
GNS (AR)
Urine glycosaminoglycans
Sly syndrome (MPS VII)
GUSB (AR)
Urine oligosaccharides
a-Mannosidosis
MAN2B1 (AR)
Urine oligosaccharides
Aspartylglucosaminuria
AGA (AR)
Urine organic acids
�-Ketothiolase deficiency
ACAT1 (AR)
Urine organic acids
Cobalamin A deficiency
MMAA (AR)
Urine organic acids
Cobalamin B deficiency
MMAB (AR)
Urine organic acids
l.o. Glutaric acidemia I
GCDH (AR)
Urine organic acids
Glutaric acidemia II
ETFA, ETFB, ETFDH(AR)
Urine organic acids
HMG-CoA lyase deficiency
HMGCL (AR)
Urine organic acids
Holocarboxylase synthetase deficiency
HLCS (AR)
Urine organic acids
3-Methylglutaconic aciduria type I
AUH (AR)
Urine organic acids
MHBD deficiency
HSD17B10 (X-linked recessive)
Urine organic acids
mHMG-CoA synthase deficiency
HMGCS2 (AR)
Urine organic acids
SCOT deficiency
OXCT1 (AR)
Urine organic acids
SSADH deficiency
ALDH5A1 (AR)
Urine organic acids (& ACP)
Ethylmalonic encephalopathy
ETHE1 (AR)
Urine organic acids (& ACP)
l.o. Isovaleric acidemia
IVD (AR)
Urine organic acids (& ACP)
3-Methylcrotonylglycinuria
MCC1/MCC2 (AR)
Urine organic acids (& ACP)
l.o. Methylmalonic acidemia
MUT (AR)
Urine organic acids (& tHcy)
Cobalamin C deficiency
MMACHC (AR)
Urine organic acids (& tHcy)
Cobalamin D deficiency
MMADHC (AR)
Urine organic acids (& tHcy)
Homocystinuria
CBS (AR)
Urine organic acids incl orotic acid (& PAA)
l.o. OTC deficiency
OTC (X-linked)
Urine organic acids (& PAA)
Tyrosinemia type II
TAT (AR)
Urine organic acids (& ACP)
l.o. Propionic acidemia
PCCA/PCCB (AR)
Urine organic acids (tHcy)
Cobalamin F deficiency
LMBRD1 (AR)
Urine purines & pyrimidines
Lesch�Nyhan syndrome
HPRT (AR)
Urine purines & pyrimidines
Molybdenum cofactor deficiency type A
MOCS1, MOCS2, (AR)
Urine purines & pyrimidines
Pyrimidine 5-nucleotidase superactivity
NT5C3 (AR)


Table 2bOverview of all diseases (in alphabetical order) requiring second tier biochemical testing, i.e. a specific test per disease approach; for each disease the OMIM# and gene(s) are listed.
Disease
OMIM#
Gene(s)
Diagnostic test
(X-linked) Adrenoleukodystrophy
ABCD1 (X-linked)
Plasma very long chain fatty acids
Biotin responsive basal ganglia disease
SLC19A3 (AR)
Gene analysis
Biotinidase deficiency
BTD (AR)
Biotinidase enzyme activity
Cerebral folate receptor-a deficiency
FOLR1 (AR)
CSF 5'-methyltetrahydrofolate
Cerebrotendinous xanthomatosis
CYP27A1 (AR)
Plasma cholestanol
Co-enzyme Q10 deficiency
COQ2, APTX, PDSS1,PDSS2, CABC1, COQ9(most AR)
Co-enzyme Q (fibroblasts) & gene analysis
Congenital intrinsic factor deficiency
GIF (AR)
Plasma vitamin B12 & folate
Dihydrofolate reductase deficiency
DHFR (AR)
CSF 5'-methyltetrahydrofolate
DHPR deficiency (biopterin deficiency)
QDPR (AR)
CSF neurotransmitters & biopterin loading test
Gaucher disease type III
GBA (AR)
Glucocerebrosidase enzyme activity (lymphocytes)
GLUT1 deficiency syndrome
SLC2A1 (AR)
CSF: plasma glucose ratio
GTPCH1 deficiency
GCH1 (AR)
CSF neurotransmitters & biopterin loading test
Hypermanganesemia with dystonia, polycythemia, and cirrhosis (HMDPC)
SLC30A10
Whole blood manganese
Hyperinsulinism hyperammonemia syndrome
GLUD1 (AR)
Gene analysis (& ammonia, glucose, insulin)
Imerslund Gr�sbeck syndrome
CUBN & AMN (AR)
Plasma vitamin B12 & folate
MELAS
MTTL1, MTTQ, MTTH,MTTK, MTTC, MTTS1,MTND1, MTND5, MTND6,MTTS2 (Mt)
Mitochondrial DNA mutation testing
l.o. Metachromatic leukodystrophy
ARSA (AR)
Arylsulfatase-a enzyme activity
Niemann�Pick disease type C
NPC1 NPC2 (AR)
Filipin staining test (fibroblasts) & gene analyses
l.o. Non-ketotic hyperglycinemia
AMT/GLDC/GCSH (AR)
CSF amino acids (& PAA)
PCBD deficiency (biopterin deficiency)
PCBD1 (AR)
CSF neurotransmitters & biopterin loading test
PDH complex deficiency
OMIM# according to each enzyme subunit deficiency: 312170;245348; 245349
PDHA1 (X-linked), DLAT(AR), PDHX (AR)
Serum & CSF lactate:pyruvate ratio enzyme activity, gene analysis
PHGDH deficiency (serine deficiency)
PHGDH (AR)
CSF amino acids (& PAA)
PSAT deficiency (serine deficiency)
PSAT1 (AR)
CSF amino acids (& PAA)
PSPH deficiency (serine deficiency)
PSPH (AR)
CSF amino acids (& PAA)
PTS deficiency (biopterin deficiency)
PTS (AR)
CSF neurotransmitters & biopterin loading test
Pyridoxine dependent epilepsy
ALDH7A1 (AR)
Urine a-aminoadipic semialdehyde & plasma pipecolic acid
Sj�gren Larsson syndrome
ALDH3A2 (AR)
Fatty aldehyde dehydrogenase enzyme activity
Smith Lemli Opitz syndrome
DHCR7 (AR)
Plasma 7-dehydrocholesterol:cholesterol ratio
SPR deficiency (biopterin deficiency)
SPR (AR)
CSF neurotransmitters, biopterin & Phe loading test (enzyme activity, gene analysis)
Thiamine responsive encephalopathy
SLC19A3 (AR)
Gene analysis
Tyrosine hydroxylase deficiency
TH (AR)
CSF neurotransmitters, gene analysis
VMAT2 deficiency
SLC18A2 (AR)
Urine mono-amine metabolites









Ketones and Autism Part 4 � Inflammation, Activated Microglia, CtBP, the NLRP3 Inflammasome and IL-1�

This series of posts on ketones and the ketogenic diet (KD) is nearly finished and I am glad that I made favourable comments about the KD ea...