About anti-estrogens

[yiyangzhi]

I found an article by Bill Roberts on the difference between the anti-estrogens. Hope this is useful reading:

Anti-estrogens are drugs which act to reduce estrogenic activity in the body. This can be done either by reducing the amount of estrogen, or by reducing the activity of whatever estrogen is present.

Competitive aromatase inhibitors, such as Cytadren , Arimidex , and probably Proviron , bind to the same binding site on the aromatase enzyme that testosterone does. By doing this, they allow less testosterone to bind to aromatase. So, less testosterone is converted to estradiol (estrogen).

Here’s an important thing: the effectiveness of competitive inhibitors decreases as the amount of the normal substrate increases. Suppose that you had equal amounts of inhibitor and normal substrate in the blood, and they bound to the enzyme equally well. Then the inhibitor would at any moment be taking up half the sites that the normal substrate otherwise would, so it would reduce conversion rate by 50%. But if the amount of substrate is increased 10 times while the amount of inhibitor remains the same, then the inhibitor would be outcompeted by the more numerous substrate molecules. It would therefore be rather ineffective.

For example, with more testosterone molecules available, and similar binding strengths, the enzyme will mostly bind testosterone. It will then mostly be working to produce estrogen. To obtain the 50% reduction we had before, then the amount of inhibitor would also have to be increased 10 times.

To be really effective, the inhibitor must either be present in higher concentration than the normal substrate, or must bind more tightly.

With Cytadren or Proviron, it takes quite a lot of inhibitor to outcompete high testosterone levels. With Arimidex, rather little, even 1 mg/day, can be sufficient because it binds so strongly.

The other general approach is estrogen receptor antagonism. If a molecule binds strongly to a hormone receptor, but does not activate that receptor and makes it unresponsive to the normal hormone, then it is a receptor antagonist. Clomid (clomiphene) and Nolvadex (tamoxifen ) follow this approach. These drugs are very similar structurally. They are both what are called triphenylethylenes, and are not steroids . The differences are relatively minor, but seem to affect an important characteristic of these compounds: drug metabolism.

Both tamoxifen and clomiphene are metabolized to other related compounds which can be estrogenic or anti-estrogenic. Both act as estrogens in bone tissue, perhaps after metabolism, which is a very useful property for female patients, for whom these drugs are usually intended. (Otherwise, an anti-estrogen could lead to osteoporosis.) Tamoxifen seems particularly prone to acting as an estrogen in the liver, which may account for reduced IGF-1 levels seen when this drug is taken.



Users generally seem to agree that when tamoxifen is used, gains are a little less than what otherwise would be expected. (Let’s not take this too far though: many people have made great gains while using tamoxifen as an anti-estrogen. And it’s always hard to say what "would" have been the case if a drug had not been included.) I’ve heard nothing but good about clomiphene, though.

Proviron, an anabolic steroid , is particularly interesting. I suspect that it not only acts as an antiaromatase but in an unknown DHT-like anti-estrogenic manner. This might involve estrogen receptor downregulation for example. In any case, aromatase inhibition and/or Clomid don’t seem to give the same effect on appearance and muscle hardness as when Proviron is included.

[CYCLEON]

yeah, good article - it makes it easy to understand that most basic of tenets, ie - that "the more AS you use, the more anti-estrogen is required".

[yiyangzhi]

I'm actually trying out Soy Isoflavones as an estrogenic receptor blocker in my front loaded cycle. Like Clomiphene and tamoxifen , soy isoflavones are considered as part of the "selective estrogen receptor modulators."

A study by Adlercreutz, Bannwart and Wahala, 1993, found that soy isoflavones block the conversion of androstenedione to oestrone more effectively than any other substance. Recently, researchers at Emory University in Atlanta, GA, presented data showing genistein inhibited prostrate cancer cell growth.

If Soy Isoflavones failed to prevent gyno symptoms, I have nolvadex , just in case.

[CYCLEON]

well, the problem that i see whith that is that soy has a TON of isoflavones and when they can isolate which ones have antiestrogenic effects that is great - unfortunately it is very difficult to make sure that the soy you are taking is rich enough in the particular flavones you need (or hasnt been damaged by the processing).

[Mr. Nobody]

Latest on Soy:

Soy's isoflavones are not garanteed to block transcription when they attach to the receptors, but may actually signal just like estrogen, so you are adding estrogen, not blocking it.


from testy.net:
http://www.testosterone.net/html/body_143soy.html

The reason why soy is so bad basically boils down to the isoflavones that it contains. Two of these isoflavones, genistein and daidzein, are what cause the majority of negative effects seen with soy protein use.

These two villains bind readily to Estrogen Receptors. One such receptor is the Alpha receptor and the other, of course, is the Beta receptor. The Alpha receptor is the one generally associated with breast tumors, increased body fat, water retention, etc. The Beta receptor really isn't something to worry about. Anyhow, genistein and daidzein can bind rather well to the Alpha receptor.

No big deal right? Well, it might actually be somewhat beneficial if they didn't activate transcription to any significant degree, as this would be what's considered an anti-estrogenic action. In other words, it would be good if the compound binded to the site and didn't cause any growth, while preventing any naturally-produced estrogen from binding (the estrogen "parking spots" would already be filled). However, genistein does activate transcription to a significant degree after binding to the Alpha receptor and therefore will cause growth of tissues.(1,2,3)

[yiyangzhi]

I found this article on soy isoflavones:


http://soyfoods.com/nutrition/SoyIsoflavonesGrowth.html

How do soy isoflavones fit into estrogen action? Genistein, the most abundant isoflavone in soybeans, binds only weakly with ER alpha, but complexes with ER beta almost as well as estrogen does (5). This probaby explains genistein's ability to prevent bone loss in ovariectomized rats (6). The predominance of ER beta in the cardiovascular system suggests that soy isoflavones may be partly responsible for the lower incidence of heart disease in soy-consuming countries.

In an anti soy essay, by Sally Fallon, she has this to say. "In vitro studies suggest that isoflavones inhibit synthesis of estradiol and other steroid hormones."

[yiyangzhi]

In the EF board, respected bro cockdezl remarked about soy isoflavones in a post, http://http://209.11.101.247/ubb/For...00/037201.html

Soy contains estrogenic compounds along with other phytochemicals. Soy is known to decrease estradiol and testosterone through various metabolic pathways: decrease production along with increased excretion, etc. So it decreases your own production but replaces it with weak estrogenic compounds.

Another bro, ontariowrestler quoted a article from http://www.brinkzone.com/soy.html

Though soy proteins contain these estrogenic compounds, it appears that
they are "tissue specific." One study that used Rhesus monkeys found
that soy proteins had no effects on the reproductive hormones of these
animals. Testosterone, DHEAS, sex hormone binding globulin (SHBG), testicular
weight, prostatic weight, and other measurements were taken. They found
no difference between male animals who ate soy protein that contained
the plant estrogens and those who ate soy with the estrogens removed,
leading researchers to conclude: "thus, the isoflavones (genistein and
diadzein) in soy protein improve cardiovascular risk factors without apparent deleterious effects on the reproductive system..., " and "Genistein's
effects appear to be tissue specific, with estrogen agonist effects
on plasma lipid concentrations, plasma lipoprotein distributions and
preservation of bone mass that are similar in magnitude to mammalian
estrogens, but without estrogenic effects..." They finally conclude
"Our data support an interpretation that soy beans estrogens have tissue
specificity in part because of their mixed estrogen agonist and antagonist
properties." From this and other data, it seems the phyto estrogens
in soy can lower cholesterol and improve heart disease risk without
systemic estrogenic effects (i.e. gyno, bodyfat increases, etc.) that
would normally be seen if say a bodybuilder took estrogen pills or from
the conversion of certain steroids to estrogen. This study is a little
more relevant to us humans being it was done with male monkeys which
are far more similar animals to people than rats. However, I think that
an upper level of soy protein that contains phyto estrogens could cause
systemic estrogenic effects if enough were taken, but that's only speculation
on my part. Also, the use of soy isolates by men might be better cycled
rather than taken all the time being we are not 100% sure at this time
about the long term estrogenic potential of soy proteins in athletes.
The ability of soy protein to lower cholesterol without other estrogenic
effects could be useful to bodybuilders using anabolic steroids who
tend to see a rise in cholesterol and/or LDL.

[Mr. Nobody]

3 things:
1. I doubt you can ingest enuf soy to make it act as an anti-estrogen when on androgen therapy, even if it would work as envisioned.
2. I still manitain my belief that genistein and daidzein are not garanteed to block transcription completely.
3. http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract
(I know rats are not people, but still it adds to the uncertainty factor...) and another study:
http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract

Your own post said this:

However, I think that an upper level of soy protein that contains phyto estrogens could cause systemic estrogenic effects if enough were taken, but that's only speculation on my part. Also, the use of soy isolates by men might be better cycled rather than taken all the time being we are not 100% sure at this time
about the long term estrogenic potential of soy proteins in athletes.

Bottom line, there are just too many variables and conflicts

[yiyangzhi]

Back in May, another intriguing thread was posted on EF board. http://boards.elitefitness.com/forum...ht=isoflavones

This was the highlight of what Spunky posted:

Soy protein BAD, I don't think so.
By Alex Rogers, Proteinfactory.com

Recently, an article was written by a certain Net Magazine, claiming that soy protein was a "Bad" Protein
to use if you were a bodybuilder looking to add lean muscle mass. The article concluded with the use of
research studies, that soy proteins' phytoestorgens actually lowered testosterone production in animal
studies. Hence lower testosterone levels , higher estrogen levels, no muscle gains.

But of course there are always two sides to the story, and I think I have a better case, jury listen up!!!

I would have to disagree, and nutritional experts agree, that soy protein is an excellent protein to use if
you're a bodybuilder using the protein to gain muscle mass. Here are a bunch of reasons.

Hormonal Studies

1)A study found that soy protein isolate (daidzein) may have a gender specific normalizing effect on
sex-hormone prduction. Male lab animals experienced greater testosterone and growth-hormone excretion
as well as muscle growth" This contradicts the study that found that genestein decreased testosterone
serum.

2)Another study found that soy may be actually antiestrogenic. . They may also act as antiestrogens by
competing for the binding sites of estrogen receptors or the active site of the estrogen biosynthesizing and
metabolizing enzymes, such as aromatase and estrogen-specific 17 beta-hydroxysteroid oxidoreductase
(type 1).

3)Probably the best research study contracting the one used by the author of "The bad protein" is this.

The phytoestrogens are only found in raw soy products. Not soy protein isolates, which are used as
protein supplements for bodybuilders.

"There are very little data on effects of phytoestrogens in males. Estrogenic effects in wildlife have been
described but the evidence for the role of phytoestrogens is indirect and seen under conditions of excessive
exposure."

And what is most interesting about this study is that it was conducted by one of the same researchers at the
same univeristy as the study that found genistein lowered testoserone serum levels. This researcher
concluded that even though he found genestein has estrogenic effects, it really cant be concluded because
of the above statement in his other reasearch findings. Hence, he found soy to be estrogenic, but it really
cant be "hard" evidence because there is not enough proof and it involves ridiculous conditions.

Also, respected bro cockdezl added this interesting information:

Here is the deal: soy isoflavones seem to improve health through their effects on estrogens and the ER. The reduction in cardiovascular disease, reduction in osteoporosis, reduction in cholesterol and blood lipids, etc. are all mediated through modifying endogenous estrogens and activation of the ER.

One thing we need to remember is that maximal health and bodybuilding are not always the same. Many of the health promoting agents are not optimal for muscular development, i.e. green tea polyphenols are excellent for reduction in cancer rates, unfortunately it seems to reduce testosterone levels. So what one has to decide is what does one want...maximal health? maximal muscular gains? a mixture of both?

If one is using steroids , I doubt soy isoflavones would affect a cycle (just don't rely on only soy proteins), and may even be beneficial, since the isoflavones would compete with stronger estrogens (estradiol). Now the heavy use of soy by naturals would not be advantageous.


*Note that cockdezl recommended that soy isoflavones would be beneficial during a cycle as a selective ER modulator.

*Overall, it appears that Soy Isoflavones maybe effective as a selective ER modulator. One must remember that Soy Isoflavones have very weak estrogenic effects compared to estradiol, oestrone and other strong estrogens. They bind weakly to alpha ERs, enough to block the harsher estrogens and bind strongly to beta ERs to exert beneficial effects on bone mass. Studies done on other isoflavones like Ipriflavone and methoxyisoflavone have shown to inhibit human cytochrome P-450 enzymes. These enzymes are critical for aromatization. They improve the function of the phosphatidyl-inositol transduction pathway, which influences the flux of chemical ions from within the muscle cell. This may optimize the efficacy of luteinizing hormone in the Leydig cells of the testes, which would promote healthy testosterone levels and sperm counts. Ipriflavone is sold as a drug for treating bone loss as well as a restorative and preventive treatment for osteoporosis. (The beneficial effect on binding to beta ERs).

Monostory K, Vereczkey L, Levai F et al "Ipriflavone as an inhibitor of human cytochrome P450 enzymes" British Journal of Pharmacology (1998) 123: 605-610


*There are specific supplements that contain only soy isoflavones, and not wholesale soy protein powder. For example, TwinLab's Isoflavone caps contain soy isoflavones in a base of soy germ. 4 caps equate to 80mg of soy isoflavones. Double that dose would be 160mg daily, enough to block E

[Mr. Nobody]

Seems like you made up your mind already, then by all means give it a try, use soy and its naturally occuring soy isoflavones to counteract the onslought of steroid induced estradiol. Just don't forget to update us on your experiment and watch for the signs such as bloating, gyno, bitching, chocolate cravings, uncontrollable crying, harsh recovery...

[CYCLEON]

and dont forget the "a" cup training bra

[yiyangzhi]

I will update you guys. Cycleon, my gf's will do, she's as flat as airport runways.

[CYCLEON]

ah, but they have such cute faces!!

[yiyangzhi]

I'm now at Day 11 of my cycle. I have front loaded Test Enanthate 1750mg/wk and Eq 1200mg/wk, with Anadrol 50-100mg ed and winny 50-100mg ed. I have been using soy isoflavones 80-160mg daily, with ZMA. Sofar, no bloating, gyno, bitching, chocolate cravings, uncontrollable crying, harsh recovery...

Usually, front loading will bring forward all the nasty side effects. I have not experienced any estrogenic side effects. I will update again by end of Week 3.

[Mr. Nobody]

update on your soy experiment please?

[bigreb]

Reading Ya'lls posts make me realize that i am a dumb mother fucker.

[yiyangzhi]

I reached the end of Week 4, and I'm happy to say that soy isoflavones are doing its job very well. I'm taking 160mg of SiF in divided doses daily. Still no bloating, water retention is low, and no gyno symptoms, despite front loading Test enanthate and eq, each above 1 gram a week. I'm taking ZMA with it as well. But no other anti-estrogens are involved. I'm quite prone to gyno as I got itchy nips from taking dbols the last cycle. I say its a thumbs up!

[Black Stang]

Do you know why McDonalds, Burger King, KFC, and other franchises thrive, and make millions????

It's because they found something that works, and they keep copying the exact methods over, and over in every location they start. Why? Because IT WORKS.

I'll stick to my Nolvadex to be safe.

[GenuinePL]

Originally posted by Black Stang
Do you know why McDonalds, Burger King, KFC, and other franchises thrive, and make millions????

It's because they found something that works, and they keep copying the exact methods over, and over in every location they start. Why? Because IT WORKS.

I'll stick to my Nolvadex to be safe.

Well there is many ways that we could go to this question.
Yes those things work and that's why everyone uses them, but if we don't try new things then we will never find anything better than them. We have to try out new ways and at some point we might fail with them or find a better working product. It just takes time before new things are found

[yiyangzhi]

I agree with GenuinePL 100%. Black Stang, read my other post about nolvadex lowering IGF-1 levels.
http://www.anabolicreview.com/vbulle...&threadid=4349

[Black Stang]

Well, I have Nolvadex on hand only if I need it. I'm not going to take it durring my cycle. So I'm not worried about hendering my gains. Then again my cycle is not as heavy as yours yiyangzhi. The point is taken though, and I guess I can see where there is room for experimenting with new ideas. I also see in your post that you have Nolva just incase, so atleast you have a back up plan if it fails. Keep us posted.