by Annalee Newitz
It’s possible that depression could be cured by reducing mild swelling in your brain. Neuroscientists have linked depression to brain inflammation before, and now a new study suggests further evidence for this theory. Here you can see the distinctive signature of a glial cell responding to swollen tissue in a brain — the cell’s center is elongated, and it has many more branching fibers than a typical glial cell.
Neurologist Susana Torres-Platas and colleagues recently discovered that this type of glial cell also shows up in the brains of people who killed themselves. Are we witnessing the distinctive neuroanatomy of depression?
Writing in Nature Neuropsychopharmacology, the researchers write that they dissected the brains of 10 people who had committed suicide and died after suddenly becoming depressed. They found noticeable differences between fibrous astrocytes, or star-shaped glial cells, in the brains of depressed people and a control group. Fibrous astrocytes are cells that provide support to neurons in the brain by aiding in their growth as well as neurotransmission, or chemical communication between neurons. There are two kinds of astrocytes in the brain, and the fibrous type is mostly in your brain’s white matter.
Write Torres-Platas and colleagues:
It can be hypothesized that the hypertrophic fibrous astrocytes described here in depressed suicides reflect local inflammation in the white matter. Strong lines of evidence support the neuroinflammatory theory of depression. In particular, it has been well documented that patients suffering from depression have significantly higher levels of circulating pro-inflammatory cytokines.
In other words, these super-active and enlarged astrocytes are likely a response to small areas of inflammation in the brain’s white matter. This suggests yet another way that depression can be caused by physical changes to the brain itself. It may also help to explain why people who have suffered concussions are depressed afterwards — their brains are literally swollen.
Read the full scientific paper via Nature Neuropsychopharmacology