ABSTRACT
Epidemiological studies suggest that the daily dietary intake of avonoids bene- cially affects human cardiovascular health (Arts and Hollman 2005; Hooper et al. 2008). Interestingly, most attention has concentrated on the vascular effects of
14.1 Introduction ................................................................................................309 14.2 Inuence of Molecular Structure on the Antihypertensive
Effects of Flavonoids .................................................................................. 310 14.3 Is the Vasodilator Effect of Flavonoids Endothelium Dependent? ............. 313 14.4 How Are Flavonoids Taken up by Vascular Cells? .................................... 314 14.5 Which Endothelium-Derived Mediators Are Inuenced by
Flavonoids? ..........................................................................................315 14.5.1 Nitric Oxide .................................................................................. 315 14.5.2 EDHF ............................................................................................ 317 14.5.3 Endothelin-1 ................................................................................. 317
14.6 What Is the Role of the Inhibition of NADPH Oxidase, Uncoupled NO-Synthase, and Xanthine Oxidase by Flavonoids? ............. 317
14.7 How Do Flavonoids Modulate Redox Signaling?....................................... 318 14.8 What Is the Effect of Flavonoids on Lipid Metabolism? ............................ 320 14.9 How Do Flavonoids Inuence Paraoxonase? .............................................. 321 14.10 What Is the Effect of Flavonoids on AMP-Activated Protein Kinase? ..........322 14.11 How Do Flavonoids Modulate Vascular Ion Channels? ............................. 322 14.12 How Do Flavonoids Inhibit Endothelial Inammation?............................. 323 14.13 Concluding Remark-What Is Next? ......................................................... 324 References .............................................................................................................. 324
avonoids from soy and cocoa (Hooper et al. 2008), and almost all epidemiologic studies regarding avonoids have originated from the Netherlands, Finland, and the United States (Arts and Hollman 2005). In this chapter, we will focus on the effects of the avonoid subclasses avanones, avones, avonols, and isoavones on the vascular endothelium. Information on the effect of avan-3-ols are provided in Chapter 13. The food items in the diet responsible for the intake of avonoids are well characterized (USDA 2003; Neveu et al. 2010). However, the explanation for the functional effects of avonoids on vascular endothelium has changed signicantly over time. These changes, rather than being merely the result of scientic dynamics, are rather the consequence of epistemological paradigm shifts with regards to their health effects, as initial concepts (e.g., on radical scavenging properties of the avonoids) are abandoned, and other more physiological concepts come in investigation.
