Resveratrol: Estrogen Antagonist/Agonist?

I’ve been perusing Pubmed for information on resveratrol. I had read somewhere that since resveratrol is structurally similar to diethylstilbestrol, a synthetic estrogen agonist, it also exhibits comparable estrogen agonist activity.[1] Looking at Pubmed articles I see that resveratrol acts as an estrogen agonist or antagonist depending on certain circumstances.[2] It appears that resveratrol will act either as an estrogen agonist or antagonist depending on estrogen receptor isoform (ER alpha vs ER beta) and the presence or absence of
17beta-estradiol.

Now I’m wondering what circumstances dictate the presence of 17beta-estradiol and type of estrogen receptor. I guess I’m just looking for information on why resveratrol is always considered strictly an estrogen antagonist, not agonist.

  1. Resveratrol, a polyphenolic compound found in grapes and wine, is an agonist for the estrogen receptor - PubMed

  2. Resveratrol acts as a mixed agonist/antagonist for estrogen receptors alpha and beta - PubMed

bump

As I have to leave the house now, here is how to find previous discussions (the site search engine may well not turn it up)

Use Google and search for:

site:http://tnation.tmuscle.com resveratrol (antagonist OR agonist OR SERM OR receptor)

Pretty sure that what you are interested in will be well covered between the various things you’ll find this way.

thanks

Using Google I found these two threads:

I didn’t spot those for some reason using T-Nation’s search funciton.

Does anyone know which brand/amount is best to take?

[quote]ecogenx wrote:
Does anyone know which brand/amount is best to take?[/quote]

If you’re going just for total amount of resveratrol, Rez-V has the highest concentration by far. I tried finding something similar (at $40 a bottle, it’s hard to stomach) but most supps were like $25 for 60 capsules of 20mg resveratrol. Rez-V is $40 for 60 capsules of 200mg resveratrol.

In terms of finding resveratrol as ONLY an antagonist, this is not the function of res on our physiology. Hell, even clomid has a mix of antagonist/agonist functions. It does seem, as you may have found in the other discussions, that res does show a strong antagonistic effect in tissue, as well as producing results in lab animals that would indicate some antagonistic effect (such as lowered lipogenesis, lowered cancer rates, etc.)

As far as good resveratrol supps, Rez-V actually stands up with the best, and is priced to match. Another one is Biotivia. It is along the same lines as Rez-V, and very similar in price. Frankly, it appears Rez-V may be a better bargain, espeically when you look at Biotivia’s higher potency stuff, which could arguably be the most potent and highest quality res on the market (that I’ve seen, at least).

Whatever you do, don’t buy the crap from your local supp shop. It is all oxygen-exposed, grape seed by product. When taking it, I actually experienced signs and symptoms of estrogen agonism (lowered interest in sex, training, more emotionally sensitive). Because of these experienced symptoms, I immediately discontinued use and started researching like mad. If you go for res, don’t throw your money away.

Sorry for the late ‘thanks’ for your advice. I’m still on the fence wether to buy some or not.

Biotest’s Rez product seems more economical than Poliquin’s, you get way more Rez per serving and per dollar.