Plant, Herb Compound Prevents Brain Inflammation

At the first sign of an infection, immune responders in the brain and spinal cord known as microglial cells normally begin to produce signaling molecules called cytokines that generate an inflammatory response to deal with the problem. But as people age, the microglial cells begin to degrade in function, leading to excessive cytokine production and corresponding brain damage.

"We found previously that during normal aging, microglial cells become dysregulated and begin producing excessive levels of inflammatory cytokines," explained Rodney Johnson, professor of animal sciences at the University of Illinois (UI) and author of the study. "We think this contributes to cognitive aging and is a predisposing factor for the development of neurodegenerative diseases."

But luteolin — which is found in foods like carrots, peppers, celery, peppermint, rosemary, chamomile, and olive oil — effectively produce a natural anti-inflammatory effect that stops the errant microglial cells from causing damage. Even during otherwise normal microglial function, luteolin helps to protect cell neurons from damage as well.

"The neurons survived because the luteolin inhibited the production of neurotoxic inflammatory mediators," explained Johnson.

For the study, the team compared two groups of mice, one of which was fed luteolin. Aged mice taking luteolin performed better in learning and memory tests than did their non-supplemented peers, and the cytokine levels in the brains of mice in the luteolin group were comparable to those of much younger mice.

"When we provided the old mice luteolin in the diet it reduced inflammation in the brain and at the same time restored working memory to what was seen in young cohorts," Johnson said.