cytochrome c is strongly reduced and almost completely absent
That is an interesting finding. In
the paper this comes from, they say:
Neutrophil mitochondria lacking cytochrome c and having no complex IV activity do, however, create Δψm (Figure 3), although the underlying mechanism remains unclear.
Δψm = the mitochondrial membrane potential = the electrical gradient (voltage) across the mitochondrial membrane.
So it seems that in spite of having no having no complex IV activity, these neutrophil mitochondria do produce a membrane voltage, which is necessary in order to produce ATP. Just how these neutrophil mitochondria produce this Δψ
m membrane voltage, the authors are unclear, but they ruled out various possibilities, and concluded that:
More likely, here is again a role for the remaining respiratory complexes, whose proton-pumping activity may control Δψm.
In other words, they think that that other mitochondrial complexes (I, II and III) may make up for the lack of complex IV activity, such that the neutrophil mitochondria are still able to supply energy.
Just how this situation might affect Myhill et al's results and interpretation, I am not sure.
after looking at mitochondrial function and measurement in neutrophils I am totally confused as to why and how Myhill et al came up with their results.
I think Myhill, Booth and McLaren-Howard may have chosen neutrophils (in lieu of muscle cells) to study, because muscle biopsies are invasive, painful, and leave a scar. That's not ideal for routine testing, or for repeat testing, when you may want to measure mitochondrial function in a patient several times, through the course of a treatment.
Though certainly it would be great if some research team could try to replicate Myhill et al's results on actual muscle cells.
They do include caveats in their papers about the use of neutrophils in lieu of muscle cells; for example in
Myhill 2012 they say:
Our experimental results are all obtained from neutrophils. Neutrophils are similar to skeletal muscle cells and most other cells (but not cardiac muscle cells) in that the proton gradient across the mitochondrial inner membrane is about 50 % electrical and 50 % chemical. However, at this stage we cannot claim that the mitochondria in other cell types behave similarly, even though mitochondria are systemic. However, some of the features that we observe are very similar to some of the effects seen in exercise studies of patients with ME/CFS.
Nevertheless, if you look at
Figure 4a from Myhiil 2009, with these tests on neutrophils, they achieved almost complete separation of ME/CFS patients from healthy controls; and moreover, the degree of mitochondrial dysfunction in neutrophils strongly correlated to the severity of ME/CFS (they tested moderate, severe and very severe patients, though did not test mild ME/CFS patients).
From
HERE:
ATP assays are extremely sensitive but they are not an ideal metric of mitochondrial function as cells strive to maintain a particular ATP budget and will adjust metabolism accordingly. Thus, alterations in ATP levels are usually only detectable during pathophysiological changes.
This is actually what I found the most instructive about the Myhill, Booth and McLaren-Howard papers: they examine the whole picture of energy production, and look in detail at the way cells metabolically adjust in order to try to compensate for ATP shortages resulting from mitochondrial dysfunction.
In some ME/CFS patients Myhill et al found that patients' cells try to make up for the energy shortfall by boosting anaerobic glycolysis, which can produce ATP independently of the mitochondria (but results in the problem of lactate build-up).
For me, this ambitious analysis of the whole picture is one of the most interesting aspects of the papers. They have not just reported their empirical findings of mitochondrial dysfunction in ME/CFS, but have striven to provide a wider framework of understanding of the energy metabolism in ME/CFS patients, which looks at the way that cells metabolically adjust to try to compensate for the mitochondrial dysfunction.
Huge red flags related to all three of the research papers = Huge conflicts of interest.
In terms of what you suggest are conflicts of interest, in
Myhill 2013 they write:
None of the authors have conflict of interest in the measurements carried out on blood samples and any other aspects of this audit. Dr Myhill’s income arises from treating patients and full details of the treatment and management regime are freely available on the website
www.doctormyhill.co.uk. Dr Booth is a retired academic physicist and contributes on a fully voluntary basis. Since his retirement from Biolab Medical Unit, Dr McLaren-Howard continues to carry out the ATP Profile and other biomedical tests at Acumen.
The struck out text was a proof-reading error that should not have been there, according to Dr Norman E. Booth in
this post.