Are Infections Just a Trigger of ME/CFS, or an Ongoing Cause of ME/CFS?

[halcyon]

One study found there was a STAT-1 deficiency in a subset of ME/CFS patients (refs: here and here).

Interesting quote in the second link:

Remarkably, as the RNAse L ratios increases (higher levels of the abnormal 37 kDa enzyme) the expression of STAT1 protein decreases. When the analysis is performed in the presence of protease inhibitors, this effect is not seen, suggesting the STAT1 protein is being proteolytically degraded.10It was proposed that the STAT1 protein is degraded by the same protease responsible for cleavage of the 80 kDa form of RNAse L.9

If these observations and hypothesis prove to be true, the implications for the pathogenesis of CFS would be of great significance. The loss of STAT1's signal transduction function would explain the increased susceptibility of CFS patients to infections and could account for the increased serum levels of interferons that is seen in some patients with CFS. The increased interferon levels would result from the homeostatic increased production of interferon in the face of decreased interferon responsiveness.

I've seen Cheney state something similar. He believes that the increased RNAse activity could be causing collateral damage by interfering with our own mRNAs. I have no idea if this is possible or if this is just a Cheneyism. It's tempting to wonder if this is what's going on in tissues with increased RNAse activity though, causing protein/enzyme synthesis problems. For example in muscle, ME patients have been found to have myoadenylate deaminase deficiency. I'm not sure why this particular finding hasn't received more attention because the symptoms of myoadenylate deaminase deficiency look pretty damn familiar.

 

[halcyon]

One study found there was a STAT-1 deficiency in a subset of ME/CFS patients (refs: here and here).

Also, enterovirus 2A protease is known to interfere with STAT1 signalling, though I'm not sure if it does so by degrading STAT1 directly as suggested. It does cleave several other host proteins though so it's not far fetched.

 

[Jonathan Edwards]

One area of the immune system that has been considered as an explanation for why ME/CFS patients do not clear intracellular infections is STAT-1 deficiency.

One study found there was a STAT-1 deficiency in a subset of ME/CFS patients (refs: here and here). As I understand it, STAT-1 relays the interferon signal into the cell, and so if STAT-1 levels are low, the intracellular immune response triggered by interferon will be weak.


Interestingly, in this paper it notes that un-methylated STAT-1 is less active than methylated STAT-1 :

It occurred to me that this might provide an alternative explanation as to why the methylation protocol can improve ME/CFS symptoms: the methylation protocol may be of benefit for ME/CFS because may boost interferon activity, as a result of methylating STAT-1 and thereby making STAT-1 more active.

A STAT-1 deficiency leading to poor responses to IFN-g and maybe a failure of a negative feedback loop would to me be exactly the sort of specific story to take seriously. It might be a small subset but still a real story.

I doubt that the methylation of STAT-1 has any implications for 'methylation protocols'. My understanding is that all genes are suppressed in the methylated form, more or less. And methylation of genes occurs as a result of very specific maturation signals within individual cells. If a methylation protocol could influence gene methylation and override this local control I think the result would be disastrous - all sorts of genes you want to be turned on would be turned off - a bit like taking a drug to turn you into a zombie. The fact that nobody on PR has turned into a zombie seems to suggest that methylation protocols do not affect genes much!!

 

[Sidereal]

I have no idea if this is possible or if this is just a Cheneyism.

 

[Eeyore]

@Jonathan Edwards - That's actually not the case. Methylation doesn't always suppress gene expression - it depends what you methylate. Promoter methylation usually suppresses gene expression, whereas methylation of the gene body usually upregulates gene expression - although even that is not that simple, and it can vary between genes. Certain genes in particular are known to increase expression as methylation increases.
See: http://www.ncbi.nlm.nih.gov/pubmed/25263941

From Nature ( http://www.nature.com/nrg/journal/v13/n7/full/nrg3230.html ):
"DNA methylation is frequently described as a 'silencing' epigenetic mark, and indeed this function of 5-methylcytosine was originally proposed in the 1970s. Now, thanks to improved genome-scale mapping of methylation, we can evaluate DNA methylation in different genomic contexts: transcriptional start sites with or without CpG islands, in gene bodies, at regulatory elements and at repeat sequences. The emerging picture is that the function of DNA methylation seems to vary with context, and the relationship between DNA methylation and transcription is more nuanced than we realized at first. Improving our understanding of the functions of DNA methylation is necessary for interpreting changes in this mark that are observed in diseases such as cancer."

There are 2 major classes of DNA methyltransferases in humans, DNMT-1 and DNMT-3 (several subtypes). DNMT-1 is the primary active form in mature humans. It functions by methylating hemimethylated CpG islands - i.e. after replication, a CpG island becomes hemimethylated, as one of the original 2 methylated strands goes to each of the 2 new replicated DNA double helices. DNMT-1 recognizes where there was full methylation previously (based on hemimethylated status) and methylates the other strand. So it doesn't really methylate indiscriminately. This is how cells maintain their commitment to a particular lineage - e.g. when an endothelial cell divides, it doesn't become a neuron. The epigenetic imprinting is copied by DMNT-1. Maternal imprinting is copied from cell to cell by this mechanism as well over the course of the organism's life.

DNMT-3 is active early in the development of the organism and much less later on and plays a key role in the commitment of various cell lineages. It will methylate unmethylated and hemimethylated CpG islands.

DNMT-1 can sometimes methylate portions of DNA that are not hemimethylated, but at MUCH lower frequency. This is why having sufficient methyl donors doesn't just lead to completely indiscriminate methylation of DNA and suppress anything and create "zombies." =P

There is evidence that hyperhomocysteinemia can impair the function of DNMT-3 in maintaining methylation, particularly in leukocytes.

Too much methylation isn't necessarily a good thing either - hypermethylation has been linked to cancer through suppression or activation of various genes. Like many things, the ideal balance is somewhere in the middle, and there are tradeoffs on either extreme.

Note that one characteristic of CpG islands is that they are palindromic when considered as double stranded - so if you have it on the sense strand, you have it on the antisense strand, when reading each 5' to 3'. This is why it makes so much sense to methylate them, as the methylation can be propagated as cells divide.

I don't think that adding methyl donors (aka "the methylation protocol") can override normal cell control, but it does allow the cell to maintain methylation patterns as DNA is copied. The key is whether we're discussing de novo or hemimethylated DNA methylation, and which DNA methyltransferases are involved. There is strong mechanistic / theoretical evidence that reducing homocysteine is beneficial in reducing cardiovascular risk, although I'm not aware of a large, high quality study that looked at the endpoint of reduced cardiovascular risk. My endocrinologist and I have discussed this at length, and he's very interested in the topic, and he is strongly of the view that hyperhomocysteinemia is a modifiable risk factor - although he believes elevated LDL cholesterol is NOT! (Statins work, but not for that reason - which is why fibrates and niacin, which lower LDL's, do not lower CHD risk.) I don't think everyone should follow a methylation protocol, and I'm not certain genetic testing is critically important, but I think if you have high serum homocysteine, you should take folic acid, and if that doesn't fix it, take methylated forms + TMG etc. to bring it down.

 

[Marco]

I'd be less interested in a STAT-1 deficiency leading to increased susceptibility to infections (some of us report more infections and some very few) rather than the impact of IFN-gamma on fatigue and the CNS :

STAT1 deficiency unexpectedly and markedly exacerbates the pathophysiological actions
of IFN- in the central nervous system

http://www.pnas.org/content/99/25/16209.full.pdf

 

[heapsreal]

There is more than one interferon too, and they do different things and have different medical applications. Type 1 interferons include alpha and beta, and they work somewhat similarly, but not identically. Type 2 would be gamma interferon. These have different (and in some cases opposite) effects on immune function and cellular vs humoral immunity. Hep C is often treated with interferon alpha and MS with interferon beta. Interferon gamma is used to treat granulomatous disease.
.

An interferon inducer i have used called cycloferon, its said to be selective of anti inflammatory type interferon alpha and beta and less so against interferon gamma. This maybe why i haven't felt any negative effects that are common with interferon therapy itself. In saying that a few people on here have tried cycloferon and have felt wose on it with flu like symptoms similar to interferon therapy. So may not be totally selective?

For me it did increase nk function significantly but had minimal effect on bright nk cells and dim nk cells. I did feel better while using cycloferon , while on immunovir i didnt feel better or worse but also wasnt able to get nk function testing at the time but was a slight but significant increase in nk numbers.

 

[Jonathan Edwards]

@Jonathan Edwards - That's actually not the case. Methylation doesn't always suppress gene expression - it depends what you methylate.

Yes, I agree with the whole of your post Eeyore, but I did say 'more or less' to avoid having to add that sometimes it works the other way around etc etc. I think the main point is that you are not going to alter a specific maturation path related to cytokine responsiveness by eating vitamins - and I think you agree!

 

[leokitten]

I totally agree, whether or not we do a methylation/vitamin protocol isn't going to wildly affect the intricate process of DNA methylation that occurs during cell maturation and aging, in particular whether one gene STAT-1 gets methylated or unmethylated.

I know I'm only one data point, but I've had my homocysteine levels measured multiple times and they are always low. Yet I am in the subset with chronic high antibodies to intracellular pathogens.

 

[Eeyore]

@Jonathan Edwards - Understood - I agree certainly that the main role of DNA methylation has historically been seen as suppression of genes unnecessary for a given lineage via promoter methylation. My intention wasn't to split hairs.

And yes, I agree that you cannot target a particular cytokine response pathway by eating vitamins - although potentially, lack of necessary vitamins could result in a failure to methylate the right things in a somewhat random and distributed way, having unpredictable effects (i.e. if there are insufficient methyl groups present to propagate the methylation activation/deactivation patterns of genes as they are replicated). It also might be more important to have methyl donors in rapidly replicating cells - as once the methylation is lost, it's gone. Adding tons of methyl groups would only randomly methylate CpG islands, not target where the information was lost. It's like if you have a mutation in all your cells that matters that occurred due to lack of particular nucleotide when one cell was dividing - you can add lots of that nucleotide, but it won't be incorporated at the right place, or in a logical way. You might just randomly incorporate it all over, creating entirely unpredictable results.

So if anything, it would argue better for maintaining sufficient methyl donors in healthy people to prevent development of disease than as a treatment for the ill!

I suppose if a gene were highly enriched in CpG islands and had lost methylation, it MIGHT be possible to alter it with lots of methyl donors, but I can't imagine it would be very specific. It seems a rather blunt instrument - and if in fact you do manage to remethylate, you'll probably remethylate a lot of other things as well - just as you probably lost methylation in a lot of places to start with.

The problem is that when something can be good or bad, depending on context on a really micro level (differing from one nucleotide to the next, or one gene to the next), it's indiscriminate upregulation or downregulation is too blunt an instrument to treat specific disease target pathways. It's probably good for all of us to make sure we have enough methyl donors present in our body so we don't lose useful coded information - more or less akin to eating a healthy diet and taking vitamins to address deficiencies, and consistent with the view that usually megadoses are not more helpful than "sufficient" doses.

 

[Eeyore]

@heapsreal -

An interferon inducer i have used called cycloferon, its said to be selective of anti inflammatory type interferon alpha and beta and less so against interferon gamma. This maybe why i haven't felt any negative effects that are common with interferon therapy itself. In saying that a few people on here have tried cycloferon and have felt wose on it with flu like symptoms similar to interferon therapy. So may not be totally selective?

I don't know much about cycloferon - but interferon alpha and beta definitely give the typical interferon symptoms (fluishness, etc.) that most people feel. It sounds from what you are saying that it is selective for type 1 interferons.

For me it did increase nk function significantly but had minimal effect on bright nk cells and dim nk cells. I did feel better while using cycloferon , while on immunovir i didnt feel better or worse but also wasnt able to get nk function testing at the time but was a slight but significant increase in nk numbers.

Bright/Dim for what? In flow cytometry, cells are listed as bright or dim for various CD's - clusters of differentiation. It's not that the cells themselves are bright or dim - it's that we use immunofluorescence to label the CD's in specific ways. So for example, all T cells are CD3 bright, CD19 dim, and the reverse is true of B-cells - because B-cells can be recognized by expression of certain proteins, including CD19, but not CD3, and T cells the reverse. The combinations of CD's present allow us to identify cells as belonging to a particular functional subtype. CD3's, for example, can be further subdivided into CD4 bright / CD8 dim (helper), CD8 bright / CD4 dim (suppressor), and even what are called double-negative T-cells - which are a rather peculiar type of T-cell that lacks CD4 and CD8 expression.

So when you say bright/dim you need to say for which cluster(s) of differentiation.

 

[leokitten]

The ratio in a number of the ME epidemics was 1:1.

I believe this is a small and completely different subset from the vast majority of people with ME/CFS, somewhat like what @Marco stated I believe that the root cause of ME/CFS in this subset is different than the root cause in the vast majority of others.

Every single ME/CFS clinician and expert, all the big names, in every presentation I've seen has clearly stated in their clinic and in all their research and studies that there is a huge sex difference in this disease towards women, not 2:1 but 3:1 (75%) to 4:1 (80%). I'm sorry but I don't believe they can all be wrong?

Also I really don't believe there is any significant selection bias or gender bias in diagnosis. This is not the kind of disease in my mind that can result in this. If you really have ME/CFS it is so life altering that you are forced to have to do something about it even in its mild forms it's really debilitating, so I disagree that a man will not go to doctor after doctor trying to get answers after being hit with this. And during this process like with all of us everything gets ruled out and ultimately you get the diagnosis of ME/CFS, regardless of whether you are a man or a woman. If anything I would say if there was a gender bias in diagnosis it would be towards men but still the sex difference is 3:1 - 4:1 women.

 

[heapsreal]

@Eeyore
i mentioned nk bright cell and nk dim cells , they were my results given to me by the university .

not sure i understand what u mean with cluster differentiation with nk function. Mayby nk bight and dim fuction is different to t cell function??

 

[Hip]

@Jonathan Edwards @Eeyore

As far as I can see, methylation of STAT-1 occurs at the protein level (post-translational methylation), rather than at the DNA level. See here.

Also, enterovirus 2A protease is known to interfere with STAT1 signalling, though I'm not sure if it does so by degrading STAT1 directly as suggested. It does cleave several other host proteins though so it's not far fetched.

Yes, according to this study on enterovirus 71, the 2A protease does not appear to cleave STAT-1; rather the 2A protease blocks the interferon receptor 1, which is a different mechanism. When agonized by IFN alpha or beta, the interferon receptor 1 activates STAT-1, so if you block this interferon receptor, naturally you are going to get a reduced STAT-1 response. The interferon receptor 1 activates STAT-1 by phosphorylating STAT-1. A reduced STAT-1 response though is not the same as reduced levels of STAT-1.

And note that this 2A-induced reduced STAT-1 response would be present in everyone who catches an enterovirus infection, including healthy people who have no difficulty in clearing such infections, so this 2A protease I don't think can specifically explain why ME/CFS patients do not seem able to clear non-cytolytic intracellular enterovirus infections.

To explain that, we would have look at immune weaknesses or dysfunctions that are prevalent in ME/CFS patients, but not prevalent in healthy people. That is the sort of immune dysfunction we are looking for, in terms of explaining the immune weakness in ME/CFS.

And this situation with reduced levels of STAT-1 in ME/CFS is precisely the sort of immune dysfunction we are seeking.


What's very interesting about the reduction of STAT-1 levels in ME/CFS is that it was found to correlate to the level of fragmented RNase L. So it has been hypothesized that the same protease that is cleaving the RNAse L may also be cleaving STAT-1:

Remarkably, as the RNAse L ratios increases (higher levels of the abnormal 37 kDa enzyme) the expression of STAT1 protein decreases. When the analysis is performed in the presence of protease inhibitors, this effect is not seen, suggesting the STAT1 protein is being proteolytically degraded. 10 It was proposed that the STAT1 protein is degraded by the same protease responsible for cleavage of the 80 kDa form of RNAse L. 9

Source: here.

Calpain has been proposed as a possible culprit for this cleavage.

 

[Eeyore]

@heapsreal - What I'm saying is that "dim" and "bright" don't mean anything unless you say what is bright and what is dim - i.e. a cell is bright or dim for a particular cluster of differentiation (which are just markers on the cells that identify what they do). They are only bright or dim because of how we label them - so interpreting what it means requires understanding what we are labeling them with. I could make a given cell bright or dim depending on which labels I am applying to them and measuring.

 

[Hip]

a huge sex difference in this disease towards women, not 2:1 but 3:1 (75%) to 4:1 (80%).

If you want a possible explanation of why ME/CFS is more prevalent in women, in terms of the STAT pathways detailed above, note that alongside STAT-1 and STAT-2, which are the cellular effectors of the interferon signal, there is also STAT-3, which does the reverse, and inhibits the type 1 interferon signal.

Now it just so happens that testosterone decreases STAT3 activation, meaning that testosterone will ultimately boost the type 1 interferon response, and thus should, I would think, help with clearance of intracellular infections.

So if you have low testosterone, it may mean you will have more difficulty in clearing intracellular infections. This might help explain why ME/CFS is more prevalent in women.



This also suggests that agents which inhibit STAT-3 might be useful in ME/CFS. Glucosamine appears to be a STAT-3 inhibitor (ref: here), and interestingly enough, the significant improvement in my ME/CFS that appeared a few years ago coincided with me starting the supplement N-acetyl-glucosamine (NAG) 700 mg daily, which I have taken ever since. NAG is a form of glucosamine that crosses the blood-brain barrier.

Some STAT-3 inhibitors are listed here.

Rituximab inactivates STAT-3 in B-non-Hodgkin's lymphoma; see here.



I read incidentally that STAT-3 is involved with autoimmunity, and reducing STAT-3 activation ameliorates experimental autoimmune uveitis; see this study.

So the reduction in STAT-3 activation afforded by testosterone might conceivably also help explain why autoimmune diseases are more prevalent in women.

 

[Jonathan Edwards]

@heapsreal - What I'm saying is that "dim" and "bright" don't mean anything unless you say what is bright and what is dim - i.e. a cell is bright or dim for a particular cluster of differentiation (which are just markers on the cells that identify what they do). They are only bright or dim because of how we label them - so interpreting what it means requires understanding what we are labeling them with. I could make a given cell bright or dim depending on which labels I am applying to them and measuring.

This has become a jargon term amongst some Nk cell people. I think it is CD56 bright but not sure. They seem to be functionally different.

 

[Jonathan Edwards]

@Jonathan Edwards @Eeyore

As far as I can see, methylation of STAT-1 occurs at the protein level (post-translational methylation), rather than at the DNA level. See here.

OK sorry. So they really do mean STAT-1 rather than STAT-1 or whatever the notation is. So together with Eeyore I have been talking irrelevances. Still, I rather suspect that the same arguments apply to a degree - it would be hard to override the internal control just by eating supplements. It might be dangerous if one could. And if its protein then the methylating is not going to overcome a deficiency - just at best soup up the small amount that is there I guess.

I think the fact that rituximab inhibits STAT-3 in malignant B cells is a red herring. It is the patient's own cytolytic mechanism (ADCC, complement or apoptotic) that does the downregulating in the cell bound by antibody, not the antibody itself. Rituximab would do nothing to STAT-3 in other cells.

 

[Hip]

By the way, in the book Chronic Fatigue Syndrome: A Biological Approach edited by Patrick Englebienne and Kenny De Meirleir, there is quite a bit discussion of RNase L, and also of calpain and elastase, which are two suspected causes of the cleaving of RNase L, and possibly STAT-1.

Rich Van Konynenburg argued in this post that elastase cannot cleave RNase L inside living cells. So that he said points to calpain.

I am not sure why this line of research was not continued. Perhaps they found something that threw the whole theory into doubt. Or perhaps there was a lack of finding.

 

[Jonathan Edwards]

By the way, in the book Chronic Fatigue Syndrome: A Biological Approach edited by Patrick Englebienne and Kenny De Meirleir, there is quite a bit discussion of RNase L, and also of calpain and elastase, which are two suspected causes of the cleaving of RNase L, and possibly STAT-1.

Rich Van Konynenburg argued in this post that elastase cannot cleave RNase-L inside living cells. So that he said points to calpain.

I am not sure why this line of research was not continued. Perhaps they found something that threw the whole theory into doubt. Or perhaps there was a lack of finding.

Maybe a lack of finding indeed!!