[Frontiers in Bioscience 17, 2396-2418, June 1, 2012]

The effects of dietary flavonoids on the regulation of redox inflammatory networks

Valerio Izzi1, Laura Masuelli2, Ilaria Tresoldi3, Pamela Sacchetti2, Andrea Modesti1, Fabio Galvano4, Roberto Bei1

1Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Rome, Italy, 2Department of Experimental Medicine, University of Rome Sapienza, Rome, Italy, 3Department of Public Health and Cell Biology, University of Rome Tor Vergata, Rome, Italy, 4Department of Drug Science, University of Catania, Catania, Italy

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. The biogenesis of reactive oxygen and nitrogen species
3.1. Reactive oxygen species (ROS)
3.2. Reactive nitrogen species (RNS)
4. ROS and RNS as immune effectors in host defense
5. ROS, RNS and redox-sensitive pathways in inflammation
6. Dietary flavonoids
7. Dietary flavonoids as ROS/RNS scavengers and inhibitors
8. Effects of dietary flavonoids on cytokines and inflammation
9. Ongoing clinical trials
10. Perspective
11. Acknowledgements
12. References

1. ABSTRACT

Dietary flavonoids are a large family of polyphenols ubiquitously expressed in plants. Recent evidence show that flavonoids possess several anti-inflammatory activities due to their ability to scavenge reactive oxygen and nitrogen species (ROS and RNS), to inhibit the pro-inflammatory activity of ROS-generating enzymes including cyclooxygenase (COX), lipoxygenase (LOX) and inducible nitric oxide synthase (iNOS) and to modulate different intracellular signaling pathways from NF-kB to mitogen-activated protein kinases (MAPKs) through perturbation of redox-sensible networks in immune cells. This report will review current knowledge on the anti-inflammatory effects of flavonoids on immune cells focusing on their ability to modulate multiple redox-sensible pathways involved in inflammation.