Resveratrol of antioxidant activity

A comparison with its different derivatives shows that 4 -OH is not a sole reactive group responsible for the antioxidant activity of resveratrol, while the trans-conformation is absolutely necessary for the inhibition of cell proliferation [187], However, similar to flavonoids resveratrol may exhibit prooxidant properties, for example to promote DNA fragmentation, although its prooxidant activity seems to be unimportant under physiological conditions [188],... 

Olas B, Wachowicz B, Saluk-Juszczak J, Zielinski T, Kaca W, Buczynski A. 2001. Antioxidant activity of resveratrol in endotoxin-stimulated blood platelets. Cell Biol... 

Resveratrol (1) is famous for its antioxidant activities, which could reduce or diminish oxidative stress and provide cardiovascular protection [448-451,494,495]. Recently, the structural basis of antioxidant activity of resveratrol (1) has been evident based on ab initio calculations and experimental crystal structure [496]. 

Fremont, L., Belguendou, L. and Delpal, S. (1999) Antioxidant activity of resveratrol and alcohol-free wine polyphenols related to LDL oxidation and polyunsaturated fatty acids, Life Sci., 64(26), 2511-2521. 

The antioxidant activity of resveratrol (Fig. 5), a stilbenoid derivative, has been reported [130]. 

In support of the antioxidant activity of resveratrol, a number of studies have demonstrated protective effects on oxidative cardiovascular injury." - In animal models, preinfusion of resveratrol prevents reperfusion-induced arrhythmias and mortality due to its antioxidant, free radical-scavenging activity as well as its ability to increase NO release. " These in vivo findings are supported by in vitro observations indicating that resveratrol significantly inhibits the ischemia/reperfusion-induced leukocyte recruitment and superoxide-related microvascular barrier dys-... 

Medina I, Alcantara D, Gonzalez MJ, Torres P, Lucas R, Roque J, Plou FJ, Morales JC (2010) Antioxidant activity of resveratrol in several fish lipid matrices effect of acylation and glucosylation. J Agric Food Chem 58 9778-9786 Lunn J (2006) Superfoods. Nutr Bull 31 171-172... 

In addition to their possible prooxidant activity (see above) polyphenols and flavonoids may influence cancer cells via their antioxidant properties. Recently, Jang et al. [219] studied cancer chemopreventive activity of resveratrol, a natural polyphenolic compound derived from grapes (Chapter 29). These authors showed that resveratrol inhibited the development of preneoplastic lesions in carcinogen-treated mouse mammary glands in culture and inhibited tumorigenesis in a mouse skin cancer model. Flavonoids silymarin and silibinin also exhibited antitumor-promoting effects at the stage I tumor promotion in mouse skin [220] and manifested antiproliferative effects in rat prostate cancer cells [221]. 

In a related study, resveratrol significantly reduced colonic injury, neutrophil infiltration, and drastically reduced the PGD2 concentration by inhibiting COX-2, but not affecting COX-1 [Martin et al., 2004]. It appears that the antiinflammatory activity of resveratrol may be realized through the inhibition of both COX-1 and COX-2-mediated pro-inflammatory signaling, suppression of pro-inflammatory mediator production, as well as from its potent antioxidative effects. 

Hydroxytyrosol has been also referred to as a potent agent with anticarcinogenic activity. Grape pomace is rich in a large number of polyphenolic compounds with high antioxidant activity, with resveratrol being probably the most known and referred to in the scientific literature. 

Trans-resveratrol (trans-3,5,4 -trihydroxystilbene) is a non-flavonoid polyphenol found in grapes, mulberries, and other food prod-ucts. It is responsible for the antioxidant activity of red wine. Intake of moderate amount of red wine has been found to reduce the risk of cardiovascular diseases. In addition to antioxidant activity, resveratrol could inhibit platelet aggregation, and showed anticancer activity. The phenoxyl radicals of resveratrol produced during oxidation by hydroxyl radicals, one-electron oxidants, and peroxyl radicals showed absorption maximum at 410 nm (Fig. I). Reports indicate that trans-resveratrol is a better radical scavenger than vitamins E and C and its activity is similar to that of the flavonoids epicatechin and quercetin. From the comparison of the spectral and kinetic properties of the transients derived from trans-resveratrol and its analogues, it could be concluded that in the neutral and acidic solutions, the para-hydroxy... 

In products with complex combinations of various types of flavonoids and other phenolic compounds, effort has been made to ascribe the antioxidant activity of the product to different classes of polyphenols. Frankel et al. (1995) studied 20 selected California wines and related the antioxidant activity to the polyphenolic components of the wines, rather than to resveratrol. Antioxidant activity was measured by the ability of the wines to inhibit copper-catalyzed oxidation of human LDL. The correlation coefficient between antioxidant activity and total phenolic components of the wines was r = 0.94. Individual phenolic compounds (gallic acid, catechin, myricetin, quercetin, caffeic acid, rutin, epicatechin, cyanidin, malvidin-3-glucoside) contributed to the antioxidant activity. The correlation coefficient for the compounds ranged from r = 0.92 to r = 0.38 in descending order. 

The higher antioxidant capability of resveratrol synthesizing fruits, compared to wild type, has also been confirmed by the analysis of total antioxidant activity (Fig. 51.6). Resveratrol contributes to such an increase since both hydrosoluble and liposoluble fractions have higher antioxidant activities in the transformed in comparison with wild-type fruits, whereas ASC and GSH only affect the hydrosoluble fractions. Interestingly, the increase in the antioxidant activity of the fruits affects lipid peroxidation, the value of which is significantly lower in transformed fruits in respect to that in wild types [34]. 

Rimando, A.M., Cuendet, M., Desmarchelier, C., and Mehta, R.G., et al. 2002. Cancer che-mopreventive and antioxidant activities of pterostilbene, a naturally occurring analogue of resveratrol. J. Agric. Food Chem. 50 3453-3457. 

Classic antioxidants, vitamin E, vitamin C, and others can suppress the activation of apoptosis. For example, ascorbic acid prevented cytochrome c release and caspase activation in human leukemia cells exposed to hydrogen peroxide [128], Pretreatment with A -acctylcystcinc, ascorbate, and vitamin E decreased homocysteine thiolactone-induced apoptosis in human promyelocytic leukemia HL-60 cells [129]. Resveratrol protected rat brain mitochondria from anoxia-reoxygenation damage by the inhibition of cytochrome c release and the reduction of superoxide production [130]. However, it should be mentioned that the proapoptotic effect of ascorbate, gallic acid, or epigallocatechin gallate has been shown in the same human promyelocytic leukemia cells [131]. 

There are numerous other polyphenolic compounds possessing in vitro and in vivo antioxidative activity. Several examples of these compounds are cited below. One of nonflavonoid polyphenols of particular interest is resveratrol (3,5,4 -trihydroxy-Znmv-stilbcne, Figure 29.8), which has been identified as a potential cancer chemopreventive agent and an antimutagen [182]. It has been found that resveratrol is the efficient inhibitor of cyclooxygenase and the inhibitor of free radical-mediated cellular processes. For example, resveratrol is a better free radical scavenger than a-tocopherol or ascorbic acid but has nearly the same activity as... 

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