Inflammation goes down when the sex hormone increases around an injury
WASHINGTON — Estrogen can protect the brain from harmful inflammation following traumatic injury, a new study in zebra finches suggests. Boosting levels of the sex hormone in the brain might help prevent the cell loss that occurs following damage from injuries such as stroke.
Estrogen levels quadrupled around the damaged area in both male and female zebra finches after researchers gave them experimental brain injuries, Colin Saldanha and colleagues at American University in Washington, D.C., reported November 17 at the annual meeting of the Society for Neuroscience. When the scientists prevented finch brains from making estrogen, inflammatory proteins at damaged sites increased.
The helpful estrogen didn’t come from gonads. It’s made within the brain by support cells called astrocytes close to the injury.
Injury inflames the brain. Initially, this inflammation recruits helpful cells to the damaged area and aids in recovery. But the long-term presence of inflammatory proteins can cause harm, killing off brain cells and reducing functions such as movement and memory. The researchers hope that by understanding how estrogen reduces inflammatory proteins, therapies might boost this natural estrogen production to keep harmful inflammation at bay.
A. Penderson. Estradiol, synthesized by reactive glia, is a potent anti-inflammatory in the injured vertebrate brain. Society for Neuroscience Meeting, Washington, DC, November 18, 2014.
S. Williams. A Different Side of Estrogen. Science News. Vol. 173, p. 8. January 5, 2008.