Inflammablog 5!

Inflammatory Bowel Disease and Depression

http://health.msn.com/health-topics/digestive-health/ibd-and-crohns/kids-with-crohns-disease-colitis-often-struggle-at-school-study

For the March 5th, 2012 discussion about the Inflammatory Bowel Disease (IBD), there is one interesting lay article Dr. Cohen posted for our interesting discussion which was that the students who have had the symptoms of IBD were struggling academically by missing classes. The study from the Nationwide Children's Hospital in Columbus, Ohio noted that the students who have IBD are at a higher risk of getting the "internalizing" problems such as depression. This depression can lead kids not doing well in school. As I read this lay article, I wanted to know more about the possible relationship or association between the IBD and depression.

I came across with this Neuroscience paper to answer my curiosity:
From inflammation to sickness and depression: when the immune system subjugates the brain.
Dantzer, R. et al. Nature Reviews Neuroscience 9, 46-56 (January 2008).

It turns out that the inflammatory cytokines such as Interleukin-1a, Interleukin-1b, Interleukin-6, and TNF-a from IBD can play a role in the brain to induce the "sickness behavior" which is very similar to and hard to differentiate from the depression according to the paper. Out of these cytokines, Interleukin-6 released from the stimulated cells can cause the down-regulation of Treg and up-regulation of Th1 and Th17 which are very strong pro-inflammtory. These can activated M1, classically-activated macrophages and lead to chronic inflammation, in this case on the mucous membrane of the gut for IBD.

Overall, the inflammation can negatively affect the health of the brain in this case causing the depression via cumulative actions from cytokines.