Long term depression associated with 'neuroinflammation'

http://www.dailymail.co.uk/health/article-5438153/Years-depression-linked-brain-inflammation.html

Not a new observation by any means but this is the first time I've seen measures of neuroinflammation quantified and correlated with duration.

 

Have they managed to prove which leads to which yet?

 

I'd like to see more brain autopsy studies on those with long term psychiatric symptoms, specifically looking for chronic infections in the brain. If there is brain inflammation (immune activation), there must be a cause of this inflammation.

Now it has been shown that infection/inflammation in the gut and other organs can ramp up brain inflammation, by signaling sent from the gut to the brain via the vagus nerve. So the situation in the gut that can be an exacerbating factor in brain inflammation, but is it enough on its own to cause neuroinflammation, without some more local inflammatory factor in the brain such as infection?

I'd like to see studies on deceased patients with psychiatric conditions examining brain tissue for evidence of pathogenic infection using methods such as high throughput sequencing, which will detect pathogens by their genetic signature.



If you look at ME/CFS, all three ME/CFS brain autopsy studies that looked for enterovirus found this infection in the brain, but none of the controls had this infection. And most of the studies that looked for enterovirus in actual muscle tissue samples of ME/CFS patients found it there. And of course we know from John Chia's studies that chronic enterovirus is to be found in the gut tissues too.

So with this infection present both in the brain and the gut, there may be two ongoing factors that cause neuroinflammation: the local infection in the brain, and the peripheral infection in the gut, which we know can further ramp up any brain inflammation via the vagus nerve.

 

One interesting angle on the link between chronic neuroinflammation and ME/CFS is post-concussion syndrome (PCS). People may suffer PCS after a physical blow to the head, and PCS is known to involve neuroinflammation (microglial activation) and to exhibit ME/CFS-like symptoms.

Interestingly, this review of PCS says:

So that seems shows that by reducing brain inflammation using CHPG, you can reduce brain fog.



PCS usually resolves on its own within six months; that's presumably because once the brain damage repair process terminates, the microglial activation ceases. Whereas in ME/CFS, if you have a chronic brain inflammation, one might assume that microglial activation will never cease, as long as the infection is still present in the brain.

 

I'm not sure this is the case. PCS not resolving after any physical brain damage is assumed to have healed brings out the usual 'psychological factors' explanations but PCS can persist for many more months or years and to assume a non-physiological reason is just lazy.

 

What I've read is that most cases of PCS resolve within 6 months, but that some persist for more than a year. But I don't know very much about PCS.

Interestingly, the review paper I quoted above said that there are two definitions of PCS in use, the DSM-IV definition, and the WHO ICD-10 definition, and that these two definitions will select different sets of patients. Table 1 of that paper indicates how the two definitions stack up:

DSM-IV and WHO ICD-10 definitions of Post-Concussion Syndrome
​

 

@Hip

This paper is pretty much as I remember it :

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3784364/

As I read that - if symptoms don't resolve within the expected week to 10 days then PCS is suspected if not diagnosed de facto. Anyway, it's an interesting 'syndrome' and one of the few I'm aware of where alcohol intolerance is common.