# Resveratrol



## Jackass (Jan 9, 2008)

any1 ever heard of this? From what i have found it is a compound found in grapes and wine. It is being sold as and anti estrogen supplement because it supposedly binds to estrogen recepetors. From a study i read it had been applied to breast cancer cells and the effect was pro estrogenic  however when in contact with estrogen receptors it binded to them , soo i think thats why its being marketed as an agonist for the estrogen receptor. Sounds to good to be true, just thought id ask anyway


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## naase2004 (Feb 16, 2008)

*Chemical and physical properties*

Resveratrol (3,5,4'-trihydroxystilbene) is a polyphenolic phytoalexin. It is a stilbenoid, a derivate of stilbene, and is produced in plants with the help of the enzyme stilbene synthase.

It exists as two geometric isomers: cis- (Z) and trans- (E), with the trans-isomer shown in the top image. The trans- form can undergo isomerisation to the cis- form when exposed to ultraviolet irradiation.[4] Trans-resveratrol in the powder form was found to be stable under "accelerated stability" conditions of 75% humidity and 40 degrees C in the presence of air.[5] Resveratrol content also stayed stable in the skins of grapes and pomace taken after fermentation and stored for a long period.[6]

*Physiological effects*

*Life extension*
The groups of Howitz and Sinclair reported in 2003 in the journal Nature that resveratrol significantly extends the lifespan of the yeast Saccharomyces cerevisiae.[22] Later studies conducted by Sinclair showed that resveratrol also prolongs the lifespan of the worm Caenorhabditis elegans and the fruit fly Drosophila melanogaster.[23] In 2007 a different group of researchers was able to reproduce the Sinclair's results with C. elegans[24] but a third group could not achieve consistent increases in lifespan of Drosophila or C. elegans.[25]

In 2006, Italian scientists obtained the first positive result of resveratrol supplementation in a vertebrate. Using a short-lived fish, Nothobranchius furzeri, with a median life span of nine weeks, they found that a maximal dose of resveratrol increased the median lifespan by 56%. Compared with the control fish at nine weeks, that is by the end of the latter life, the fish supplemented with resveratrol showed significantly higher general swimming activity and better learning to avoid an unpleasant stimulus. The authors noted a slight increase of mortality in young fish caused by resveratrol and hypothesized that it is its weak toxic action that stimulated the defense mechanisms and resulted in the life span extension.[26] Later the same year, Sinclair reported that resveratrol counteracted the detrimental effects of a high-fat diet in mice. The high fat diet was compounded by adding hydrogenated coconut oil to the standard diet; it provided 60% of energy from fat, and the mice on it consumed about 30% more calories then the mice on standard diet. Both the mice fed high-fat diet plus 22 mg/kg resveratrol and standard diet had a 30% lower risk of death than the mice on the high-fat diet. Gene expression analysis indicated the addition of resveratrol opposed the alteration of 144 out of 155 gene pathways changed by the high-fat diet. Insulin and glucose levels in mice on the high-fat+resveratrol diet were closer to the mice on standard diet then to the mice on the high-fat diet. However, addition of resveratrol to the high-fat diet did not change the levels of free fatty acids and cholesterol, which were much higher than in the mice on standard diet. [27]


*Cancer Prevention*
In some lineages of cancer cell culture, resveratrol has been shown to induce apoptosis, which means it kills cells and may kill cancer cells.[28][29][30][31][32][33] Resveratrol has been shown to induce Fas/Fas ligand mediated apoptosis, p53 and cyclins A, B1 and cyclin-dependent kinases cdk 1 and 2. Resveratrol also possesses antioxidant and anti-angiogenic properties.[34][35]

Resveratrol is under extensive investigation as a cancer chemopreventive agent.[36][37] Indeed, there are studies showing that small doses of dietary resveratrol can reduce colon carcinogenesis in rats and mice.[38] One German study has already been shown to that under special conditions, resveratrol induces apoptosis in human fat cells. In addition, it inhibits production of cytokines which are involved in the development of obesity-related disorders.[39]


*Athletic performance*
Johan Auwerx (at the Institute of Genetics and Molecular and Cell Biology in Illkirch, France) and coauthors published an online article in the journal CELL in November 2006. Mice fed resveratrol for 15 weeks had better treadmill endurance than controls. The study supported Sinclair's hypothesis that the effects of resveratrol are indeed due to the activation of SIRT1.

Nicholas Wade's interview-article with Dr. Auwerx[40] states that the dose was 400 mg/kg of body weight (much higher than the 22 mg/kg of the Sinclair study). For an 80 kg (176 lb) person, the 400 mg/kg of body weight amount used in Dr. Auwerx's mouse study would come to 32,000 mg/day. Compensating for the fact that humans have slower metabolic rates than mice would change the equivalent human dose to roughly 4571 mg/day. Again, there is no published evidence anywhere in the scientific literature of any clinical trial for efficacy in humans. There is limited human safety data (see above). It is premature to take resveratrol and expect any particular results. Long-term safety has not been evaluated in humans.

In a study of 123 Finnish adults, those born with certain increased variations of the SIRT1 gene had faster metabolisms, helping them to burn energy more efficiently—indicating that the same pathway shown in the lab mice works in humans too.[41]


*Antiviral effects*
Resveratrol seems to increase the potency of some antiretroviral drugs against HIV in vitro.[42]

Infection by herpes simplex virus ordinarily activates the cell protein Nuclear Factor κB (NF-κB). A Northeastern Ohio Universities College of Medicine study undertaken in Vero cells found that resveratrol suppresses the activation of this transcription- and apoptosis-related protein. The study further found that multiple viral protein products were reduced or completely blocked, as well as a reduction in viral DNA production.[43]

A cell culture study found that resveratrol blocks the influenza virus from transporting viral proteins to the viral assembly site, hence restricting its ability to replicate. The effect was 90% when resveratrol was added six hours after infection and continued for 24 hours thereafter.[44]


*Adverse effects and unknowns*
While the health benefits of resveratrol seem promising, one study has theorized that it may stimulate the growth of human breast cancer cells, possibly because of resveratrol's chemical structure, which is similar to a phytoestrogen.[45][46] However, other studies have found that resveratrol actually fights breast cancer.[47][48] Citing the evidence that resveratrol is estrogenic, some retailers of resveratrol advise that the compound may interfere with oral contraceptives and that women who are pregnant or intending to become pregnant should not use the product, while others advise that resveratrol should not be taken by children or young adults under 18, as no studies have shown how it affects their natural development.[49] A small study found that a single dose of up to 5 g of trans-resveratrol caused no serious adverse effects in healthy volunteers.[50]

There is some evidence that resveratrol might exacerbate West Nile virus, since West Nile is p53 mediated and worsened by increased rates of apoptosis of infected cells. [7]


*Mechanisms of action*
The mechanisms of resveratrol's apparent effects on life extension are not fully understood, but they appear to mimic several of the biochemical effects of calorie restriction. This seems to function by means of lipase inhibition, reducing the absorption of fat through intestinal walls. A new report indicates that resveratrol activates SIRT1 and PGC-1α and improve functioning of the mitochondria.[51] Other research calls into question the theory connecting resveratrol, SIRT1, and calorie restriction.[52][53]

An article in press as of January 2008 discusses resveratrol action in cells. It reports a 14-fold increase in the action of MnSOD.[54] MnSOD reduces superoxide to H2O2, but H2O2 is not increased due to other cellular activity. Superoxide O2- is a byproduct of respiration in complex 1 and 3 of the electron transport chain. It is "not highly toxic, [but] can extract an electron from biological membrane and other cell components, causing free radical chain reactions. Therefore is it essential for the cell to keep superoxide anions in check."[55] MnSOD reduces superoxide and thereby confers resistance to mitochondrial dysfunction, permeability transition, and apoptotic death in various diseases.[56] It has been implicated in lifespan extension, inhibits cancer (e.g. pancreatic cancer [57]), and provides resistance to reperfusion injury and irradiation damage [58] [59] [60]. These effects have also been observed with resveratrol. Ellen et al propose MnSOD is increased by the pathway RESV --> SIRT1 / NAD+ --> FOXO3a --> MnSOD. Resveratrol has been shown to cause SIRT1 to cause migration of FOXO transcription factors to the nucleus [61] which stimulates FOXO3a transcriptional activity [62] and it has been shown to enhance the sirtuin-catalyzed deacetylation (activity) of FOXO3a. MnSOD is known to be a target of FOXO3a, and MnSOD expression is strongly induced in cells overexpressing FOXO3a [63].

Resveratrol interferes with all three stages of carcinogenesis - initiation, promotion and progression. Experiments in cell cultures of varied types and isolated subcellular systems in vitro imply many mechanisms in the pharmacological activity of resveratrol. These mechanisms include modulation of the transcription factor NF-kB,[64] inhibition of the cytochrome P450 isoenzyme CYP1A1[65] (although this may not be relevant to the CYP1A1-mediated bioactivation of the procarcinogen benzo(a)pyrene[66]), alterations in androgenic[28] actions and expression and activity of cyclooxygenase (COX) enzymes.

Resveratrol was reported effective against neuronal cell dysfunction and cell death, and in theory could help against diseases such as Huntington's disease and Alzheimer's disease.[67][68] Again, this has not yet been tested in humans for any disease.

Research at the Northeastern Ohio Universities College of Medicine and Ohio State University indicates that resveratrol has direct inhibitory action on cardiac fibroblasts and may inhibit the progression of cardiac fibrosis.[69]

According to Patrick Arnold it also significantly increases natural testosterone production from being both a selective estrogen receptor modulator[70][71] and an aromatase inhibitor.[72][73]

In December, 2007, work from Irfan Rahman's laboratory at the University of Rochester demonstrated that resveratrol increased intracellular glutathionelevels via Nrf2-dependent upregulation of gamma-glutamylcysteine ligase in lung epithelial cells, which protected them against cigarette smoke extract induced oxidative stress. [74]


*Pharmacokinetics*
Resveratrol bioavailability depends on its conjugate forms: glucuronate and sulfonate, but most in vitro studies use the aglycone form of resveratrol ('aglycone' means without a sugar molecule attached, as in the figure in this article). In humans[75] [76] and rats,[77] [78] [79] resveratrol rapidly undergoes conjugation resulting in less than 5% of the oral dose being observed as free resveratrol in blood plasma. The effect of conjugation on efficacy is debated.[80][81] The studies[76] [77] show rats have 72% more free resveratrol and 6 times more of a glucuronide form as humans for a dose of about 60 mg/kg. The most abundant conjugates in humans, rats, and mice are trans-resveratrol-3-O-glucuronide and trans-resveratrol-3-sulfate.[82] Walle suggests sulfate conjugates are the primary source of activity[75], Wang et al suggests the glucuronides,[83] and Boocock et al also emphasized the need for further study of the effects of the metabolites including the possibility of deconjugation to free reservatrol inside cells.

In humans, Walle et al reported at least 70% absorbed and 99% is quickly metabolized to conjugates using 25mg doses. Half life of resveratrol and its metabolites was 9 hours. 73% was excreted in urine and feces after 12 hours. [75] Boocock et al reported 3% of the total metabolites in the blood plasma of humans was free resveratrol, measured as area under the concentration curve. Half life was 4 to 11 hours for the various metabolites. [76]

A study on rats given an oral dose of 50 mg/kg showed resveratrol and its metabolites have an initial apparent half life of 8 minutes but a "terminal" half life of 1.5 hours in blood plasma. The free resveratrol was 46 times less than the glucuronide form (measured as area under the concentration curve).[77]

When trying to calculate an equivalent dose for humans, it is not accurate to use the mg dose per body weight method as was commonly reported in the media when the life-extension resveratrol studies came out.[84] This method leads to much larger quantities than is accurate because larger animals have a slower metabolic rate for their weight. The comparative dosage should be based on mg per Calories consumed per day. If the Calories consumed per day are not known, it is estimated from the body weight.[85] This results in the formula: (human dose/kg) = (animal dose mg/kg) x (animal kg/human kg)^(1-P) where P=2/3 is used by convention to give a larger margin of safety for FDA pharmaceutical and EPA toxicology uses, but P=3/4 is more accurate.[86] [87] The absorption, metabolism, and excretion is very different in different species so that even adjusting for metabolic rate is not very accurate. For example, as mentioned in the absorption section, rats have much more free resveratrol and glucuronide forms in their blood than humans for a given dose, eventhough the metabolic rate adjustment implies they should have much less.


*Related compounds*
Scientists are also studying three other synthetic compounds based on resveratrol which more effectively activate the same biological mechanism.[88]

The compound called SRT 1720 seems to be 1000 times more effective than resveratrol, although it only increases SIRT1 activation by 6 times. No data has been publicly produced by Sirtris regarding this difference in SIRT1 efficiency for the new compound.[89]

A study by Professor Roger Corder has identified a particular group of polyphenols, known as oligomeric procyanidins, which they believe offer the greatest degree of protection to human blood-vessel cells. These are found in greatest concentration in European red wines from certain areas, which correlates with longevity in those regions. This new data may impact the supplement market.[90] Because they are present in red wine in more significant quantities, they could offer an alternate explanation of the French paradox.


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## craig20 (Mar 31, 2009)

Very interesting..

I saw something about resveritrol on Oprah the other day..


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## ASHOP (May 20, 2009)

This is a supplement we are definitely looking into further.


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## MeasureOfAll (May 21, 2009)

As far as I know resveritrol is supposed to make body cells act as if they are on a low caloric diet as if the animal fasts regularly. It strengthens existing cell walls which helps with the prevention of cancer. Problem is a real clinical dosage would have to be aqquired by distilling 2,000 bottles of red wine. What's on the market now is weak compared to what they gave those fish.


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