Resveratrol, effects

In other studies, we also showed that resveratrol effectively suppressed proliferation of cultured bovine pulmonary aortic endothelial cells (BPAEC). These results imply that resveratrol, delivered to endothelial cells in sufficient concentrations to inhibit proliferation in vivo, could facilitate rapid and efficient repair of damages on the endothelium, with the overall effect of decreasing the probability of sustained endothelial injury and exposure of the subendothelial matrix, which would trigger the formation of atherosclerotic plaques and the development of... 

Owing to the fact that ethyl ethers are especially effective substrates for CYP1A1 [184], the probe possesses an ethyl group on the phenolic oxygen of the trimethyl lock. In vitro, fluorescence was manifested by CYP1A1 isozyme with Kcat/KM 8.8 x 103 M-1s 1 and KM 0.09 pM. In cellulo, the probe revealed the induction of cytochrome P450 activity by the carcinogen 2,3,7,8-tetrachlorodi-benzo-p-dioxin (TCDD), and its repression by the chemoprotectant resveratrol. 

Romero-Perez AI, Lamuela-Raventos RM, Andres-Lacueva C and Torre-Boronat MC. 2001. Method for the quantitative extraction of resveratrol and piceid isomers in grape berry skins. Effect of powdery mildew on the stilbene content. J Agric Food Chem 49(1) 210-215. 

Olas and Wachowicz (2002) investigated the effects of tranx-resveratrol and vitamin C on oxidative stress in blood platelets. The level of 02 in control blood platelets and platelets incubated with resveratrol or vitamin C was recorded using a chemiluminescence method. On the other hand, Oh and others (2006) reported the x02 quenching activities of various freshly squeezed fruit and vegetable juices by measuring their inhibitory effects on the rubrene oxidation induced by x02 from disproportionation of hydrogen peroxide by sodium molybdate in a microemulsion system. 

A similar effect was observed in other fruits and vegetables, where UV-C treated strawberries showed a higher increment of phenols and PAL activity 12 hours after treatment than unirradiated (control)(Pan and others 2004), which could be the reason for the increment in total phenol constituents (Lancaster and others 2000). UV-C and UV-B caused a two- and threefold increase in content of resveratrol (a grape phenol constituent). Thus, mature Napoleon grapes that had been irradiated with UV-C light can provide up to 3 mg of resveratrol per serving (Cantos and others 2001). Therefore, UV-C treatments clearly cause a benefit effect, increasing total phenol content, which can be mainly attributed to the increment of PAL activity. 

People in France eat a lot of fatty foods but suffer less from fatal heart strokes than people in the northern regions of Europe or in North America, where wine is not consumed on a regular basis ( French paradox ). There is an increased favorable effect from red wine. The unique cardioprotective properties of red wine are due to the action of flavonoids, which are minimal in white wine. The best-researched flavonoids are resveratrol and quercetin, which confer antioxidant properties more potent than a-tocopherol. 

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]. 

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]. 

Proteasome inhibition by lactacystin and Bz-LLL-COCHO (benzol-Leu-Leu-Leu-glyoxal) causes a significant increase of ABP and cell death by altering APP processing at the y-secretase site (406). Resveratrol does not inhibit ABP production because it has no effect on 3-, or y-secretases, but promotes instead intracellular degradation of ABP via a mechanism that involves the proteasome. The resveratrol-induced decrease of ABP can be effectively prevented by several selective proteasome inhibitors and by small interfering RNA-directed silencing on the proteasome subunit P5 (407). 

Resveratrol has a long history. It was initially isolated from the roots of white hellebore in 1940. No one paid much attention. In 1963, it was isolated from a plant used for centuries in traditional Japanese and Chinese medicine. Again, this did not attract much attention. The story got a lot hotter in 1992 when the presence of resveratrol in red wine was suggested to be associated with the cardioprotective effects of red wine. 

How resveratrol works is not understood. There have been efforts to link resveratrol action to the effect of calorie restriction. " Here is why. 

Schmatz R, Schetinger MR, Spanevello RM, Mazzanti CM, Stefanello N, Maldonado PA, Gutierres J, Correa Mde C, Girotto E, Moretto MB, Morsch VM. (2009) Effects of resveratrol on nucleotide degrading enzymes in streptozotocininduced diabetic rats. Life Sci 84 345-350. 

Palsamy P, Subramanian S. (2009) Modulatory effects of resveratrol on attenuating the key enzymes activities of carbohydrate metabolism in strep-tozotocin-nicotinamide-induced diabetic rats. Chem Biol Interact 179 356-362. 

Resveratrol is another type of polyphenol, a stilbene derivative, that has assumed greater relevance in recent years as a constituent of grapes and wine, as well as other food products, with antioxidant, anti-inflammatory, anti-platelet, and cancer preventative properties. Coupled with the cardiovascular benefits of moderate amounts of alcohol, and the beneficial antioxidant effects of flavonoids, red wine has now emerged as an unlikely but most acceptable medicinal agent. 

The effect with which PPT modulate the response of platelets is also pertinent to vascular disease, in particular, thrombosis. Resting platelets inhibit the respiratory burst of neutrophils whereas thrombin-activated platelets increase the respiratory burst. Quercetin and resveratrol at picomolar concentrations attenuate this response by preserving endothelial CD39/ATP-dase," " and on present evidence (see above) such concentrations might be achieved locally following deglucuronidation at a site of inflammation. 

Kaneider, N.C., Mosheimer, B., Reinisch, N., Patsch, J.R., and Wiedermann, C.J., Inhibition of thrombin-induced signaling by resveratrol and quercetin effects on adenosine nucleotide metabolism in endothelial cells and platelet-neutrophil interactions, Thromb. Res., 114, 185, 2004. 

Fig. 32. Effects of resveratrol on tumor volume (a) andfinal tumor weight (b) in LLC-bearing mice.

Table 8. Effects of resveratrol on apoptosis Go/Gl, S aad G2/M phase of cell cycle in LLC cells1...

Fig. 33. Effects of resveratrol on the numbers of colonies of LLC cells metastasizing to the lung on day 22 in LLC-bearing mice.

Fig. 34. Effects of resveratrol on 3H-thymidme incorporation into DNA of LLC cells.

F ig. 35. Effects of resveratrol on Matrigel-induced capillary-like network formation by HUVEC. 

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