In Ron Davis's video, he says that adding pyruvate to their assays makes ME cells 'normal.' To me, this is a fascinating finding and gives us a strong clue/piece of the puzzle, (providing that the impedance test transfers well to real life of course, which i'm optimistic it will).
In his above videos Dr Ron Davis does not mention the abnormalities he found in ME/CFS patient's cells, which then returned to normal on treating the cells with pyruvate. So it's hard know exactly what he means by pyruvate returning the cells to normal, unless he simply means ATP energy production returned to normal.
Presumably it relates to his group's current working hypothesis of ME/CFS being caused by a problem in glycolysis and in the pyruvate kinase enzyme.
Cort's article details this working hypothesis:
As most people probably know, the Davis group’s working hypothesis right now is that problems with glycolysis – the process producing many of the raw materials the mitochondria use for energy – is impaired in chronic fatigue syndrome (ME/CFS).
Their data is leading them to suspect an enzyme called pyruvate kinase is this issue. The Fluge/Mella group has come to a similar conclusion, but they’re more focused on a different enzyme called pyruvate dehydrogenase.
Pyruvate is the final output product from glycolysis, and pyruvate contains a lot of energy which can only be extracted if the pyruvate molecule is shuttled into the mitochondria, where when things are working normally, it gets converted into acetyl-CoA (via pyruvate dehydrogenase enzyme), and then enters the Krebs cycle to yield its energy.
Fluge and Mella's study suggested an impairment in the
pyruvate dehydrogenase enzyme in ME/CFS patients, resulting in a reduced ability to convert pyruvate to acetyl-CoA. So Fluge and Mella's work suggests impaired pyruvate dehydrogenase is the energy blockage in ME/CFS patients.
In such a scenario, there is no shortage of pyruvate produced by glycolysis, and so adding extra pyruvate to the cells would probably not help restore the energy metabolism. The extra pyruvate will not help, because without the pyruvate dehydrogenase enzyme working properly, that extra pyruvate cannot be utilized.
However, by contrast in Ron Davis's theory, it is thought there may be an issue with glycolysis and the
pyruvate kinase enzyme. The pyruvate kinase enzyme is the final step of glycolysis: this enzyme manufactures pyruvate. Thus an impairment in pyruvate kinase functioning would result in a shortage of pyruvate. In this scenario, it makes sense that adding pyruvate to the cells would restore normal cell functioning, in terms of ATP energy production.
If a dysfunctional pyruvate kinase enzyme is the blockage in energy metabolism of ME/CFS patients, then I guess we would want to uncover why pyruvate kinase function is impaired.
According to the
Wikipedia article on pyruvate kinase, glucagon, cyclic AMP and epinephrine inhibit pyruvate kinase, and thereby shut down glycolysis. Reactive oxygen species (ROS) inhibit the M2 isozyme of pyruvate kinase (PKM2) in human lung cells. Alanine inactivates pyruvate kinase. Fructose 1,6-bisphosphate is an activator of pyruvate kinase. So these are some factors that might be involved in down-regulating pyruvate kinase functioning.
Some cyclic AMP boosters and inhibitors listed in
this post.