Submitted to: Current Medicinal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 22, 2000
Publication Date: N/A
Interpretive Summary: Citrus fruit contain a number of related compounds, termed the flavonoids, which express certain biological actions in animals. Two of the main biological actions include the inhibition of cancer and inflammation. There are several mechanisms by which citrus flavonoids inhibit inflammation, and most of these involve the inhibition of specific biochemical reactions in the inflammation response. In feeding studies, citrus flavonoids help prevent the occurrence of cancer in test animals. These molecules are also able to inhibit the growth of cultured cancer cells. It is proposed that many of these biological actions are linked to actions exerted by the metabolites, or breakdown products of the citrus compounds in humans. The metabolism of flavonoids in animals is summarized, and new findings are discussed relative to the importance of the binding of these molecules to adenosine receptors.
Technical Abstract: Citrus flavonoids encompass a diverse set of structures, including numerous flavanone and flavone O- and C-glycosides and methoxylated flavones. Each of these groups of compounds exhibits a number of in vitro and in vivo anti-inflammatory and anticancer actions. These biological properties are consistent with their effects on the microvascular endothelial tissue. Evidence suggests that the biological actions of the citrus flavonoids are possibly linked to their interactions with key regulatory enzymes involved in cell activation and receptor binding. The citrus flavonoids show little effect on normal, healthy cells, and thus typically exhibit remarkably low toxicity in animals. The citrus flavonoids extend their influence in vivo through their induction of hepatic phase I and II enzymes, and through the biological actions of their metabolites. Evidence clearly indicates the potential health promoting properties of these dietary compounds.