Antioxidants pycnogenol

WEI z, PENG Q and lau b h s (1997) Pycnogenol enhances endothelial cell antioxidant defences Redox Report 3, 147-55. 

Packer, L. and C. Colman The Antioxidant Miracle, Put Lipoic Acid, Coq 10, Pycnogenol, and Vitamins E and C to Work for You, John Wiley Sons. Inc., New York. NY, 1999. 

Grape seed extract, which is another widely used plant extract similar to pycnogenol, contains procyanidins, which have a strong antioxidant activity. 

Packer, L., Rimbach, G., and Virgili, F. Antioxidant activity and biologic properties of a procyanidin-rich extract from pine (Pinus martima) bark, pycnogenol, Free Radic. Biol. Med., 27, 704—724, 1999. 

Antioxidant and disease prevention capacities of proanthocyanidins from cocoa, grape seed, cranberries, and Pycnogenols (French pine... 

Pycnogenol has been reported to have a strong antioxidant activity either in vitro utilizing cultured cells or in vivo in experimental animals and in humans, and to participate to the cellular antioxidant network. Further beneficial effects such as vasorelaxation, immunomodulatory function, and anti-iirflammatory activities have been reported, coirfimting the potential of this extract as an effective phytochemical. 

Recently, some reports have led to the hypothesis that Pycnogenol could be beneficial in not only mitigating the adverse effects of anticancer chemotherapy," but possibly also inhibiting the development, growth, and progression of cancer. This activity is associated not only with the strong antioxidant capacity of the polyphenols contained in Pycnogenol, but also with its ability to modulate cell response to different stimuli. 

This chapter discusses the antioxidant capacity of Pycnogenol and reviews some of the recent advances and hypotheses regarding its ability to significantly affect cell signaling and cell response in carcinogenesis. 

The use of pine bark extracts has its roots in ancient traditional medicine in different countries of the world. In general, the utilization of Pycnogenol in the past was considered suitable for many of those conditions where vitamin C deficiency is now known to be involved, such as scurvy, skin disorders, and wound heating. Ttiis utilization anticipated the understanding of the complex nature of the interaction between different antioxidants and the important role that polyphenols may play in the recycling and interplay with other antioxidants and, finally, in human health and disease. 

More recently, it has been shown that supplementation with Pycnogenol in human subjects is associated with a significant increase of total plasma antioxidant capacity. This observation confirms that the antioxidant capacity of the mixture is bioavailable, indirectly supporting the bioavailability of Pycnogenol components. 

Pycnogenol has also recently been reported to be absorbed percutaneously by humans and may therefore exert its anti-inflammatory and antioxidant activity from this route, protecting the skin from ultraviolet (UV)-radiation-induced damage. ... 

The most obvious feature of Pycnogenol, owing to the basic chemical structure of its components, is its strong antioxidant activity. Phenolic acids, polyphenols, and in particular flavonoids are composed of one (or more) aromatic rings bearing one or more hydroxyl groups and are therefore potentially able to quench free radicals by forming resonance-stabilized phenoxyl radicals. " The ability to quench the reactivity of... 

Various studies have addressed the antioxidant capacity of Pycnogenol in simplified assay systems in vitro, cultured cell models, perfused organs, and in vivo. Blazso and coworkers tested the in vitro scavenging activity of Pycnogenol as well as three... 

Besides the quenehing effects described above, phenohcs, and in particular Pycnogenol, may act as preventive antioxidants by ehelating transition metals, thus preventing the formation of hypervalent metal forms involved in the initiation of the peroxidation process. The ability of phenolie moleeules to act as metal chelators appears obvious owing to the presenee of adjaeent hydroxyl groups in the same aromatic ring. Despite this, relatively few studies have been performed to characterize such... 

The use of Pycnogenol as a dietary supplement may help to reduce the risk of cancer. There is ample clinical and experimental evidence indicating that Pycnogenol s strong and bioavailable antioxidant capacity places it at the top rank of biological substances to be considered beneficial for human redox balance. 

As an effective bona fide antioxidant in both plasma and intracellular membrane, Pycnogenol can significantly contribute to the maintenance of cellular redox homeostasis, in particular in the course of events that are likely to overwhelm the capacity to cope with an increased production of RONS, such as in chronic inflammations, thereby reducing Ae possibility of cellular damage at different targets. The ability of Pycnogenol to act as a lipid peroxidation chain breaker is also likely to reduce the toxic consequences of a free-radical-induced cellular stress. 

Drehsen, G., From ancient pine bark uses to Pycnogenol, in Antioxidant Food Supplements in Human Health, Hiramatzu, M., Packer, L., and Yoshikawa, T., Eds., Academic Press, San Diego, 1998. 

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