Lycopene as antioxidant

Rao AV, Agarwal S. Role of lycopene as antioxidant carotenoid in the prevention of chronic diseases a review. Nutr Res 1999 19 305-323. 

In summary, lycopene must have some specific effect on unknown cellular processes that control the modulation of multiple pathways. General properties, such as antioxidation or pro-oxidation, are unlikely to explain these effects. Since the activation, silencing or loss of pathway control is different for each cell type and its degree of transformation, we do not have enough information to predict whether lycopene may be beneficial or detrimental under different circumstances in various prostate cell lines and in the different stages of prostate cancer. 

Some non-enzymatic antioxidants play a key role in these defense mechanisms. These are often vitamins (A, C, E, K), minerals (zinc, selenium), caretenoids, organosulfur compounds, allyl sulfide, indoles, antioxidant cofactors (coenzyme Qio)> and polyphenols (flavonoids and phenolic acids) [1,37]. Further, there is good evidence that bilirubin and uric acid can act as antioxidants to help neutralize certain free radicals [38]. Alpha-carotene, lycopene, lutein, and zeaxanthine [39] can be considered subgroups of carotenoids [40] that are effective antioxidant compounds. 

Carotenoida group of yellow, orange, and red pigments found in plant and animal tissues. Some carotenoids, such as beta-carotene, lutein, and lycopene, have antioxidant properties. 

The ability of lycopene to act as an antioxidant and scavenger of free radicals is frequently cited as the most likely mechanism that could account for the hypothesized beneficial effects on human health.Supporting this theory, protection against oxidative stress has been shown in parallel with a preferential destraction of lycopene relative to P-carotene in a study of human skin irradiated with ultraviolet (UV) light. Further, the ability of carotenoids to act as antioxidants has been hypothesized as the mechanism underlying the protection of the human retina from photooxidation, a process that over time can result in the pathologies of age-related macular degeneration (AMD) and cataracts. ... 

Chronic pancreatitis has long been thought to be mainly associated with immoderate alcohol consumption, tobacco smoke, and obesity, diets high in animal protein and fat, as well as antioxidant deficiencies. Diets high in processed or red meat, diets low in fruits and vegetables, phytochemicals such as lycopene and flavonols, have been proposed and refuted as risk or protective factors in different trials [131]. In a case-control study of 462 cases and 4,721 controls, there was a significant inverse association between lycopene intake and pancreatic cancer, after... 

Fertile sources of carotenoids include carrots and leafy green vegetables such as spinach. Tomatoes contain significant amounts of the red carotenoid, lycopene. Although lycopene has no vitamin A activity, it is a particularly efficient antioxidant (see Antioxidants). Oxidation of carotenoids to biologically inactive xanthophyUs represents an important degradation pathway for these compounds (56). 

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