Peripheral Inflammatory Disease (COVID-19 and Inflammatory Bowel Disease) and Brain Gliosis

Inflammation is the body's natural response to infection or injury, like the redness that happens around a scrape on the skin. In conditions where inflammation is very active, it is possible for the inflammation to affect the brain. This is especially seen in two conditions where clinical depression occurs very frequently: COVID-19 and inflammatory bowel disease (IBD). After recovering from COVID-19, approximately 15% of people experience clinical depression. Similarly, depression occurs three to five times more frequently in people with IBD than in the general population. Unfortunately, there are no treatments designed for depression from COVID-19 and IBD because little is known about how inflammation affects the brain in these conditions. We think that inflammation from other parts of the body spreads to the brain in COVID-19 and IBD, but this has not been studied yet. Using new brain scanning methods, we are able to measure levels of inflammation in the brain. In our previous research, we used these methods to show that brain inflammation occurs in clinical depression and that higher levels of inflammation may lead to more severe depressive symptoms. And now, our new data shows that these levels may be higher in COVID-19 and IBD. Brain scans in a few people that have recovered from COVID-19 showed a 15% to 30% increase in inflammation and a brain scan in one person with IBD showed an increase over 50%. In our new study, we propose scanning more participants with these conditions to see if brain inflammation is consistently higher than in the general population. If this is the case, then medications that can reduce inflammation in the brain may be effective in treating depression caused by inflammatory diseases like COVID-19 and IBD. In fact, there are already some medications available for other illnesses that can reduce brain inflammation, they just need to be tested for other purposes.