Flavonoids as components of biologically active cosmeceuticals.

Flavonoids are multi-active components used in common cosmetics primarily for antioxidant and soothing actions. Despite this, their multi-active properties are far from being fully used. It is well known that many flavonoids provide protection from telangiectasias and petechias caused by ruptured blood vessels. Thus, the notion of a "strengthening" effect of these compounds on blood vessel walls is common. The activity of flavonoids on skin blood vessels is complex. Three main components of their activity can be distinguished: blood vessel protection, platelet aggregation prevention, and capillary permeability decrease. Each of these components is realized with the participation of several mechanisms differing on the types of receptors that the flavonoids affect. Some of them consist of a direct action on the enzymes responsible for the synthesis of substances of tissue hormone character, such as thromboxanes, histamine, or platelet activating factor. The mechanisms based on less or more indirect activity can also be met. At least 11 points for activity can be distinguished among flavonoids' actions on blood vessels.