AI effect on FT & TT

[James]

We all know the effect anastrosol has on E2, but how does it effect a man's free and total testosterone? Have guys injected the same dose with and without an AI? And if so, how did it effect your FT & TT?

 

[ERO]

It only affects Total T in guys NOT on TRT. For guys on TRT using an AI affects the ratio of T to E but does not change Total T levels.

 

[CoastWatcher]

An AI has no impact on exogenous testosterone levels.

 

[James]

It only affects Total T in guys NOT on TRT. For guys on TRT using an AI affects the ratio of T to E but does not change Total T levels.

So it just affects the ratio by lowering the E. That's simple.

That's interesting that it does affect the T levels in guys not in TRT.

Thanks guys.

 

[Bama Boy]

It only affects Total T in guys NOT on TRT. For guys on TRT using an AI affects the ratio of T to E but does not change Total T levels.

Great info Thanks

 

[Geofftek]

This is interesting. My T levels went up quite a bit when I was put on an AI. My Doc also said before I started the AI that it would not affect my total T. But it jumped from 32 to 38. No other change was made to my protocol. ???

 

[GeauxBears]

Am I missing something here? An AI like anastrozole, which binds to E2 receptors to prevent aromatization, should both decrease E2 AND increase total T, regardless of whether the T is exogenous or endogenous. Reason being, the rate of aromatization is reduced with anastrozole, thereby keeping more T as T and less as E...

There is also the potential in a guy with an intact HPG axis for anastrozole to further increase T, because the reduced E2 is "seen" by the hypothalamus/pituitary as a signal to produce more T.

Someone correct me if I am wrong.

 

[James]

Am I missing something here? An AI like anastrozole, which binds to E2 receptors to prevent aromatization, should both decrease E2 AND increase total T, regardless of whether the T is exogenous or endogenous. Reason being, the rate of aromatization is reduced with anastrozole, thereby keeping more T as T and less as E...

There is also the potential in a guy with an intact HPG axis for anastrozole to further increase T, because the reduced E2 is "seen" by the hypothalamus/pituitary as a signal to produce more T.

Someone correct me if I am wrong.

GeauxBears - that's how I understand it. I would think Anastrosol would cause T to rise. See below from Dr. Faloon. The article doesn't specify if the man was taking T or not.

Dr. William Faloon (2010)
An epidemic problem we at Life Extension observe in aging male members is insufficient free testosterone, i.e., less than 15-20 pg/mL of serum. When accompanied by excess estradiol (over 30 pg/mL of serum), this can signal excess aromatase enzyme activity.

Excess aromatase robs men of their testosterone while exposing them to higher than desirable estradiol.

When aromatase is properly suppressed, estradiol levels are reduced to safe ranges, while free testosterone often INCREASES, since less testosterone is being aromatized into estradiol.

 

[Gene Devine]

It only affects Total T in guys NOT on TRT. For guys on TRT using an AI affects the ratio of T to E but does not change Total T levels.

Hi ERO - Can you please provide some clinical evidence that supports your statements as I'd like to read that; from all my research it' not what I've come to learn about the effects of the use of an Aroamatase Inhibitor.

Thank you.

Gene

 

[Gene Devine]

Am I missing something here? An AI like anastrozole, which binds to E2 receptors to prevent aromatization, should both decrease E2 AND increase total T, regardless of whether the T is exogenous or endogenous. Reason being, the rate of aromatization is reduced with anastrozole, thereby keeping more T as T and less as E...

There is also the potential in a guy with an intact HPG axis for anastrozole to further increase T, because the reduced E2 is "seen" by the hypothalamus/pituitary as a signal to produce more T.

Someone correct me if I am wrong.

^^^^This!!!

An AI is competitive to Testosterone at the E2 receptor site. Simpy put, lower aroamatase synthesis and the result is increase levels of Total and Free Testosterone.

The body does not recognize bio-identical Testosterone to endogenous Testosterone when it comes to this comparison.

In here I've asked for some clinical research that supports some of these statements because it's not my understanding after years of studying TRT in men.

 

[ERO]

Hi ERO - Can you please provide some clinical evidence that supports your statements as I'd like to read that; from all my research it' not what I've come to learn about the effects of the use of an Aroamatase Inhibitor.

Thank you.

Gene

I am trying to find it again now. I should have saved it.

My understanding of the explanation is as follows: AIs have been shown to increase Total T for natural (Not on TRT) men because their bodies are still producing Testosterone and due to various feedback loops caused by the AI, their HPTA may produce more Testosterone than before adding the AI. In contrast, guys on TRT have a shut-down HTPA so, for example, if they are using 120 mg of T a week that is what their bodies have - adding an AI would not get them to 130 mg a week or 140 mg a week - Therefore the AI would effect their T:E ratio but not their Total T levels.

You bring up a good point about aromatase conversion though!

This would be a good topic for Dr. Saya to weigh-in on if he is on the forum today.

 

[Dr Justin Saya MD]

You are ALL correct, just in different ways...GeauxBears and Gene are correct in the most practical sense, but before I get to that - ERO, you are correct that an AI will not cause an increase in T for a man on TRT via HPTA stimulation, simply as you stated because the HPTA is suppressed anyways. HOWEVER, GeauxBears and Gene are correct that the AI will still "PRESERVE" some testosterone from being "lost" in the conversion to estradiol. In other words, it will prevent some of the T from being "chopped off the top" so to speak, and therefore may result in a mild-moderate increase in Total T (we must keep in mind that the concentrations of E in the male system are so much smaller than the concentrations of T that this is usually a minor impact).

As another layer of complexity, and sometimes a stronger effect, lower E with an AI *usually* translates to lower SHBG, which may then translate to higher free T...obviously many other factors, but you can see that angle.

 

[ERO]

Hello Dr. Saya. As always, you are able to take a complicated topic and explain it so that it is very easy to understand! Thank you for being an active member on this forum.

 

[James]

Thank you Dr. Saya.

AI increases T for guys NOT on TRT through the HPTA, and it also increases T for guys who ARE on TRT by way of less conversion of T to E2. However it does not increase T through HPTA for guys on TRT.

 

[James]

Hello Dr. Saya. As always, you are able to take a complicated topic and explain it so that it is very easy to understand! Thank you for being an active member on this forum.

Agreed. Invaluable!

 

[Dr Justin Saya MD]

Thank you Dr. Saya.

AI increases T for guys NOT on TRT through the HPTA, and it also increases T for guys who ARE on TRT by way of less conversion of T to E2. However it does not increase T through HPTA for guys on TRT.

That basically sums it up, BUT it should be noted that use of an AI is NOT generally (with rare exception) indicated in men who are NOT on TRT (and only when necessary for men who are). Thus, I don't really view it as an "HPTA stimulator" for non-TRT men as you would typically have to suppress E levels to sub-optimal to achieve ANY HPTA stimulation...which we all know we don't want to suppress E too much.

Aside from that *minor* point, LOL, your summary is perfect!