Dietary flavonoids and modulation of natural killer cells: implications in malignant and viral diseases.
Flavonoids are a large group of secondary plant metabolites present in the diet with numerous potentially health-beneficial biological activities. In addition to antioxidant, anti-inflammatory, cholesterol-lowering, and many other biological functions reported in the literature, flavonoids appear to inhibit cancer cell proliferation and stimulate immune function. Although the immunomodulatory potential of flavonoids has been intensively investigated, only little is known about their impact on natural killer (NK) cells. Enhancing NK cell activity, however, would have strong implications for a possible clinical use of flavonoids, especially in the treatment and prevention of diseases like cancer and viral infections. Therefore, the purpose of this review is to summarize the currently available information on NK cell modulation by flavonoids. Many of the structurally diverse flavonoids stimulate NK cell activity and have thus great potential as diet-derived immune-modulatory chemopreventive agents and may even serve as therapeutic compounds or lead structures for the development of novel drugs for the treatment of both malignant and viral diseases.
Institute of Physiology, Department of Physiology I, Medical University Hospital, Tuebingen, Germany. Electronic address: markus.burkard@uni-tuebingen.de.
Markus
M
Burkard
Institute of Physiology, Department of Physiology I, Medical University Hospital, Tuebingen, Germany. Electronic address: chlei@gmx.de.
Christian
C
Leischner
Department of Internal Medicine VIII, Medical University Hospital, Tuebingen, Germany. Electronic address: ulrich.lauer@med.uni-tuebingen.de.
Ulrich M
UM
Lauer
Division of Dermatologic Oncology, Department of Dermatology and Allergology, Medical University Hospital, Tuebingen, Germany. Electronic address: christian.busch@med.uni-tuebingen.de.
Christian
C
Busch
Institute of Physiology, Department of Physiology I, Medical University Hospital, Tuebingen, Germany. Electronic address: sascha.venturelli@med.uni-tuebingen.de.
Sascha
S
Venturelli
Institute of Biological Chemistry and Nutrition, University of Hohenheim, Stuttgart, Germany. Electronic address: jan.frank@nutres.de.
Jan
J
Frank
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D004032:Diet; D005419:Flavonoids / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D014777:Virus Diseases / Q000188:drug therapy / Q000276:immunology
D016588:Anticarcinogenic Agents; D005419:Flavonoids; D007155:Immunologic Factors
Cancer; Flavonoid; Innate immunity; Isoflavones; Natural killer cell modulation; Viral infection