This is a fascinating article by Mary Ackerley, M.D. which plainly discusses the brain/depresssion/macrophages. At the end there are recommended treatments: Vitamin D, fish oil, probiotics, magnesium, turmeric, and of course, diet.
http://paradigmchange.me/wp/?p=596
Here is just one section of the article:
"Hypothalamic-Pituitary Axis
Here’s some more basic science about what we are looking for in the brain when we talk about inflammation. This is a diagram of your brain. It’s looking at your hypothalamus and pituitary.
When you look at Dr. Shoemaker’s model, he’s going to start with damage in the hypothalamic-pituitary axis. It’s that damage that leads to the decrease in hormones that we often see — the decrease in androgens, the decrease in cortisol. Sometimes, as Dr. Shoemaker will say, you’ll see an increase in cortisol, which is your body’s last fling at trying to correct things before you sink into the decreasing cortisol.
This diagram shows the relationship between cortisol and brain inflammation and the cascade of events that happen subsequent to stress.
In this diagram it’s labeled as stress. Stress can be from many different things, such as interpersonal difficulties.
Early adversity is something that is well-studied in psychiatry. Having abusive childhoods is very common, more common than anyone would like to think. This will lead to changes in our ability to secrete cortisol.
This leads to changes in cytokines of something called Nuclear Factor Kappa Beta. It flourishes. That increases inflammation in the body.
The inflammation in the body leads to excitotoxicity. That’s another word for anxiety, really. It decreases neurotransmitters and also causes depression.
There are several agents that can cause this kind of depression besides stress. Biotoxins would be big ones. Others would be heavy metals, food allergens and viruses."