Flavonoids in prevention of diseases with respect to modulation of Ca-pump function.

Flavonoids, natural phenolic compounds, are known as agents with strong antioxidant properties. In many diseases associated with oxidative/nitrosative stress and aging they provide multiple biological health benefits. Ca(2+)-ATPases belong to the main calcium regulating proteins involved in the balance of calcium homeostasis, which is impaired in oxidative/nitrosative stress and related diseases or aging. The mechanisms of Ca(2+)-ATPases dysfunction are discussed, focusing on cystein oxidation and tyrosine nitration. Flavonoids act not only as antioxidants but are also able to bind directly to Ca(2+)-ATPases, thus changing their conformation, which results in modulation of enzyme activity.Dysfunction of Ca(2+)-ATPases is summarized with respect to their posttranslational and conformational changes in diseases related to oxidative/nitrosative stress and aging. Ca(2+)-ATPases are discussed as a therapeutic tool and the possible role of flavonoids in this process is suggested.