Submitted to: Microcirculation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 27, 2000
Publication Date: January 17, 2001
Interpretive Summary: Certain plant compounds occurring in the human diet are able to inhibit inflammation. Inflammation is a normal response of the body to injury, but there are cases where inflammation in uncontrolled, such as in cases of arthritis. In these instances, the plant compounds termed the flavonoids, may provide benefit in their inhibition of chronic inflammation. This action occurs through the inhibition by flavonoids of key biological steps in the inflammation process. This article reviews the molecular mechanisms by which the flavonoids affect inflammation.
Technical Abstract: Plant flavonoids attenuate inflammation and the immune response through their inhibition of important regulatory enzymes. Certain flavonoids are potent inhibitors of the production of prostaglandins, a group of powerful proinflammatory signaling molecules. Studies have shown that this effect is due to flavonoid inhibition of key enzymes involved in prostaglandin biosynthesis, i.e. lipoxygenase, phospholipase, and cyclooxygenase. Flavonoids also inhibit phosphodiesterases involved in cell activation. Much of this effect is upon the biosynthesis of protein cytokines which mediate adhesion of circulating leukocytes to sites of injury. The protein kinases are another class of regulatory enzymes affected by flavonoids. The inhibition of kinases is due to the competitive binding of flavonoids with ATP at catalytic sites on the enzymes. These modes of inhibition provide the mechanisms by which flavonoids inhibit the inflammation response.