Posted by linkadge on June 19, 2020, at 15:01:00
In reply to Can someone explain this COVID/MAO-B study?, posted by PeterMartin on June 19, 2020, at 7:09:19
Great article and question.
I've always been interested in MAO-B. Generally speaking, MAO-B activity is thought to increase with age. It also appears to be increased in depression (especially depression with cognitive disturbance). MAO-B inhibitors are used for Parkinson's disease, but also appear to have pro-cognitive effects (i.e. selegiline is approved for canine cognitive dysfunction). This study doesn't directly say whether MAO-B levels are elevated (or depressed) in patients with COVID associated delirium. My *assumption* would be that there could be an elevation (simply due to the fact that MAO-B elevation is associated with cognitive dysfunction, and the association of worse outcomes in elderly COVID patients).
The study found that "Phenethylamine (PEA) concentrations in delirium-prone patients was significantly lower in CSF than in blood". I'm not sure if this would be the result of MAO-B elevation or depression. MAO-B is responsible for PEA metabolism. Lower PEA in the CFS might be associated with lower PEA metabolism and hence lower MAO-B (?? not sure). I mean, if COVID caused a severe DROP in MAO-B levels, this could theoretically cause delirium too (as a result of higher PEA levels). They said there is an association between ACE2 and MAO-B. I understand that ACE2 is elevated in COVID, perhaps this means that MAO-B levels are elevated as well.
Another consideration is that elevated MAO-B levels are generally associated with brain inflammation. For example, in mice, when agents are given to increase inflammation (or stress induced inflammation) it generally increases MAO-B levels. Given the 'cytokine storm' in COVID, this might be though to induce an increase in MAO-B via inflammation. My thought is that they are suggesting an elevation of MAO-B levels, but I really don't know and, of course, it could be dangerous to self medicate with MAO inhibitors at this stage.
Linkadge
poster:linkadge
thread:1110832
URL: http://www.dr-bob.org/babble/20200511/msgs/1110845.html