The image is over my head. These articles are more my speed:

https://www.healthline.com/nutrition/how-to-increase-nitric-...

https://www.medicalnewstoday.com/articles/326381#benefits

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2953417/

https://www.nutrex.com/articles/benefits-of-nitric-oxide-boo...

https://www.ausfp.com/medical-procedures-services/nitric-oxi...

(Yes, I'm aware the last two are trying to sell you something and are probably skeevy.)

So, some general off-the-cuff thoughts:

Glutathione is a big deal with CF. There is too little on the surface of cells and too much inside the cells.

Some people with CF report good results from inhaling NAC (iirc) tro promote glutathione on the surface of the lungs.

I think people with CF have too much inside their cells because we hoard it, along with calcium, to buffer against high acidity and other chemical derangement. As I have been getting healthier, I periodically experience what I think is glutathione dumping. My armpits and bowel movements smell strongly sour, similar to a skunk, and then my baseline function permanently improves afterwards.

I took milk thistle for a while, maybe a couple of years or something. It's a glutathione precursor. You can't supplement glutathione directly. You have to take precursors so the body can manufacture it.

I did it in part as liver support. Glutathione is important to liver function which is important to cleaning the blood. I spent a whole lot of time worried about my circulatory health as that seems to be the key that pulls everything together.

I read up on altitude sickness at one time and it was hugely eye opening. The mechanism involved provides a clear connection between the lung and gut issues in CF via the bloodstream.

I lived at 3000 feet above sea level for 2.75 years. My rib cage size enlarged and has remained enlarged ever since (as evidence by changes in the band size of my bras). I likely had underdeveloped lungs.

From there, I moved to about 100 feet above sea level and was soon bedridden due to pneumonia and this led to my diagnosis just before I turned to 36. It is known that people who live at altitude and then go down in altitude experience a big boost in energy levels. I likely survived being bedridden from pneumonia in part because of my recent time at altitude.

I'm wondering if you know of any research into long-term effects of NO production for having lived at altitude for a time.

I'm thinking my more normal distribution of glutathione these days may be a factor in why I have been largely asymptomatic, in spite of being in a high risk category.

One of those articles indicates that NO deficiency also inhibits glucose and/or NO enhances glucose uptake. This would also lower energy levels.

My impression of what I am experiencing absolutely fits with the idea that poor vasodilation in the lungs, and thus poor trafficking of oxygen into the blood stream, could explain the low oxygen levels, at least in part.

I don't know how to describe it, but I feel like, yes, my lungs are cut off in some way from my body, in spite of not being full of fluid. I breathe fine, but I sometimes feel like my airways aren't really doing their job in some important way. I feel like the tissues are "closed" in some sense, in spite of not being gunked up and covered over.

Insufficient vasodilation impairing oxygen uptake fits with that impression.

I think that's all I had in mind to say.

Edit: I have just spoken with my son (who also has atypical CF) about this discussion and he says lack of vasodilation -- and oxygen thus failing to cross adequately into the blood stream -- also fits with what he is experiencing. None of us has an active cough. We are mostly just really tired.