Microglia Shown to Benefit Injured Brains (Video)

Immune cells generally believed to aggravate chronic brain diseases have now been found to have a beneficial effect in traumatic brain injury. The normal immune function of these cells, known as microglia, is to consume cellular debris and dead neurons from nerve tissue. Until now, it was believed that microglia promoted inflammation damaging to healthy brain tissue after a traumatic injury. But a team of researchers led by Bruce Trapp, PhD, of Cleveland Clinic’s Lerner Research Institute found that microglia actually help synchronize brain firing, which protects the brain from traumatic brain injury. The findings were published in Nature Communications. “We could potentially harness the protective role of microglia to improve prognosis for patients with traumatic brain injury and delay the progression of Alzheimer disease, multiple sclerosis and stroke,” says Dr. Trapp.

“Most of the research has focused on a pathogenic or a destructive role of microglia, and I think that’s because they remove cellular debris, and many people have confused removing cellular debris with causing the damage,” says Dr. Trapp in the video.

In the study, all the microglia in the brain were activated, and then the brain was given a lesion. “Lo and behold, the lesion was smaller and not bigger, and then we went in depth to see what the microglia were doing during this protective stage,” Dr. Trapp adds. By surrounding the neurons, the microglia enabled them to continue firing in a synchronous manner. This actually shielded the brain and reduced the size of a subsequent injury.

Dr. Trapp concludes the video with a hopeful statement about the discovery: “If we could learn how to harness the protective role of microglia, we could develop therapies that may stop the progressive neurodegenerative diseases.”