May 20, 2008 -- A compound found in celery and green peppers may help protect against inflammatory brain conditions.
The compound, called luteolin, is a potent antioxidant known for its anti-inflammatory properties. Luteolin belongs to a family of plant molecules called flavonoids, which are found in various vegetables, fruits, and beverages, including chamomile tea.
Researchers have rigorously studied the potential health effects of flavonoids for more than a decade. Previous studies have shown that flavonoids can help counter dementia caused by brain inflammation.
For the current study, Saebyeol Jang of the division of nutritional sciences at the University of Illinois at Urbana-Champaign and colleagues investigated how luteolin acts on cells called microglia taken from mice. Microglia are scattered throughout the central nervous system and are principally responsible for the brain's immunological defense. Excessive production of inflammatory molecules produced by microglia in the brain can worsen neurodegenerative changes seen in animal studies on Alzheimer's disease and an inflammatory brain condition called Creutzfeld-Jakob disease.
Jang's team exposed mice microglia cells to bacteria and then treated them with the luteolin. Their experiment showed that luteolin reduced the inflammation triggered by the bacteria. The researchers also learned that the celery compound blocked a "promoter" to the gene that coded for an inflammatory signaling molecule.
In a second experiment, the researchers gave mice drinking water containing luteolin for three weeks, and then injected the animals with bacteria. Blood tests showed that the luteolin-spiked water reduced measures of inflammation in the blood and brain four hours after the injection. Specifically, researchers noted a reduction in inflammation in the brain's hippocampus, the area related to memory and learning.
The researchers conclude that luteolin "may be useful for mitigating neuroinflammation." They published their findings in the Proceedings of the National Academy of Sciences.