Hydroxyproline elevated in ME/CFS

Reading Jen Brea's latest post on Medium, I came across some interesting information.

I have created this thread to discuss these findings about hydroxyproline and collagen. It so happens that I heard about this through a post written by Jen Brea. However, please keep this thread to discussing these findings, not for discussing your views about Jen's recovery and her theories in general.

 

http://www.hmdb.ca/metabolites/HMDB0000725

4-Hydroxyproline (hydroxyproline or Hyp) is a major component of the protein collagen. Hydroxyproline is produced by hydroxylation of the amino acid proline and is, therefore, a post-translationally modified, non-essential amino acid. Hydroxyproline and proline play key roles in collagen stability. In particular, they permit the sharp twisting of the collagen helix. Hydroxyproline is found in few proteins other than collagen. The only other mammalian protein which includes hydroxyproline is elastin. For this reason, hydroxyproline content has been used as an indicator to determine collagen and/or gelatin amount in tissue or biological samples. Increased serum and urine levels of hydroxyproline have been found in Paget's disease (PMID: 436278 ). Hydroxyproline (Hyp) content in biological fluids is used as a parameter of collagen catabolism, especially bone resorption or tissue degradation. Bedridden and elderly individuals show significantly elevated serum levels of hydroxyproline in comparison to normal, active individuals (PMID: 10706420 ). Elevated levels of urinary hydroxyproline are also indicative of muscle damage (PMID: 21988268 ). Increased reactive oxygen species (ROS) are also known to accelerate collagen degradation. Hydroxyproline levels increase in cases of depression and stress (PMID: 21483218 ). 4-Hydroxyproline is found to be associated with Alzheimer's disease, and also hydroxyprolinemia and iminoglycinuria which are both inborn errors of metabolism. 4-Hydroxyproline is also involved in metabolic disorders such as hyperprolinemia type I, hyperornithinemia with gyrate atrophy (HOGA), L-arginine:glycine amidinotransferase deficiency, creatine deficiency, and guanidinoacetate methyltransferase deficiency. A deficiency in ascorbic acid can result in impaired hydroxyproline formation (PubChem). trans-4-Hydroxy-L-proline is a biomarker for the consumption of processed meat.

 

I have this pet peeve theory that is probably wrong but well intentioned that some of us might have trouble with on-demand blood flow because something something vascular something something loss of elasticity, something shear stress. It is not very thoroughly thought out but I do respond reasonably well to both vasodilators and -constrictors (citrulline & caffeine), cognitively speaking.

Would increased expression of some regular collagenase enzyme explain the increase in hydroxyproline we see here or does something else have to be unusual? There's also this thing about some Coxsackie subtypes increasing matrix metalloproteinases but I understand next to nothing about that topic.

Could any of this be triggered by exercise, i.e. would it be part of regular cleanup in training induced tissue remodeling to build some collagenase or MMP or whatever-is-relevant-that-I-do-not-know?

 

Here is the tweet thread from Jen Brea.


@Sarah94 Can you please adjust the title to reflect that this is a Medium article written by jen Brea
e.g. Blog - Hydroxyproline elevated in ME/CFS?, July 2019 (Jen Brea)

Digging into the data a bit Hanson data does not show this


Men do NOT show elevated hydroxyproline according to Naviaux supplementary data. Only data from women.


Also Naviaux initial study was meant to be duplicated and also blindly verified in 2017, but the results have not been published. So take the initial Naviaux study with caution unless other studies back up the conclusions.

 

My guess would be the latter. In order to confirm this, the researchers need to have sedetary / bedridden / deconditioned individuals as a control groups rather than healthy and active individuals. It is beyond me why this isn't done more often in ME / CFS research. Deconditioning could have a multitude of physiological effects, which can distinguish CFS patients from healthy controls in studies, which in turn often leads researchers on the wrong path.

 

https://www.ncbi.nlm.nih.gov/books/NBK21582/

I am interested in the basal lamina

basal lamina (pl. basal laminae)
A thin sheetlike network of extracellular-matrix components that underlies most animal epi-thelial layers and other organized groups of cells (e.g., muscle), separating them from connective tissue.

 

https://www.sciencedirect.com/science/article/pii/B9780080450469012857

The extracellular matrix occupying the space between the nerve terminal and the muscle cell is the synaptic basal lamina. The synaptic basal lamina serves at least two important roles. First, it is a mechanical link that tightly attaches the nerve terminal to the twitching muscle cell. Second, there are molecules in the synaptic basal lamina that are crucial for the cell-to-cell signaling that is required for the function of the synapse. Molecules in the synaptic basal lamina are regulated by proteases that remove specific components. Thus, the synaptic basal lamina is integral to the structure and function of the synapse.

 

Functions of the basal lamina.

https://www.histology.leeds.ac.uk/tissue_types/connective/con_basal_lam.php

 

Studies done at Ninewells Hospital Dundee found that elastin, which makes blood vessels supple, is wrong in ME. They found that the patients had more rigid blood vessels.

 

But is there any evidence that people with ME are deconditioned?

By all means we need to compare like-with-like but we need evidence that PWME and CFS are deconditioned before we assume that it is relevant to research.

 

http://www.jbc.org/content/278/15/12601

The Basement Membrane/Basal Lamina of Skeletal Muscle*

 

https://www.intechopen.com/books/co...amina-a-highly-selective-extracellular-matrix

Abstract
In this chapter, we discuss a specialized version of the extracellular matrix, the basal lamina. We focus on biophysical approaches which helped in identifying the mechanistic principles that allow the basal lamina to act as a selective permeability barrier. We discuss the physicochemical interactions that entail binding of molecules or nanoparticles to the basal lamina matrix and outline physiological scenarios where altered selective permeability properties of the basal lamina might contribute to physiological (mal) function.

 

With ME/CFS, I would imagine that it depends on how severe the person's ME is? I'm mild to moderate, and I'm definitely not deconditioned, however, for someone who is mostly housebound, and especially bedbound, then there is a much greater chance of that person being deconditioned.

 

https://www.ncbi.nlm.nih.gov/pubmed/22051349

Abstract
Protein misfolding is a common theme in aging and several age-related diseases such as Alzheimer's and Parkinson's disease. The processes involved in the development of these diseases are many and complex. Here, we show that components of the basement membrane (BM), particularly laminin, affect protein integrity of the muscle cells they support. We knocked down gene expression of epi-1, a laminin α-chain, and found that this resulted in increased proteotoxicity in different Caenorhabditis elegans transgenic models, expressing aggregating proteins in the body wall muscle. The effect could partially be rescued by decreased insulin-like signaling, known to slow the aging process and the onset of various age-related diseases. Our data points to an underlying molecular mechanism involving proteasomal degradation and HSP-16 chaperone activity. Furthermore, epi-1-depleted animals had altered synaptic function and displayed hypersensitivity to both levamisole and aldicarb, an acetylcholine receptor agonist and an acetylcholinesterase inhibitor, respectively. Our results implicate the BM as an extracellular modulator of protein homeostasis in the adjacent muscle cells. This is in agreement with previous research showing that imbalance in neuromuscular signaling disturbs protein homeostasis in the postsynaptic cell. In our study, proteotoxicity may indeed be mediated by the neuromuscular junction which is part of the BM, where laminins are present in high concentration, ensuring the proper microenvironment for neuromuscular signaling. Laminins are evolutionarily conserved, and thus the BM may play a much more causal role in protein misfolding diseases than currently recognized

 

I don't think there is such a test so it's impossible to make that claim either way. The fluctuating nature alone falsifies it and the PACE researchers admitted themselves (in meeting notes) that participants are moderately active and therefore could not under any consideration be considered deconditioned. The fact that the GET arm nonetheless uses that model makes it clear they do not even believe in their own claims, they are merely convenient lies.

So it's an assumption, basically a belief since it's impervious to contradicting evidence, or seen a necessary deceit. Prejudice is a terrible motivator in medical research.