New Research Suggests The Conversion Of Testosterone To Estrogen In The Brain Is Crucial For Male Se

[b555]

New research suggests the conversion of testosterone to estrogen in the brain is crucial for male sexual desire

 

[JoeKool]

Oh yes, this is why heavy doses of AIs (or even light doses for some) kill a man’s libido as Estrogen sensitizes the androgen receptors, which then uptakes dht to act on that desire. And the balance of these hormones, amongst others, is extremely delicate. Good study!

 

[b555]

Oh yes, this is why heavy doses of AIs (or even light doses for some) kill a man’s libido as Estrogen sensitizes the androgen receptors, which then uptakes dht to act on that desire. And the balance of these hormones, amongst others, is extremely delicate. Good study!

this has been my experience with ai too

 

[DennisX]

Oh yes, this is why heavy doses of AIs (or even light doses for some) kill a man’s libido as Estrogen sensitizes the androgen receptors, which then uptakes dht to act on that desire. And the balance of these hormones, amongst others, is extremely delicate. Good study!

arimidex does not cross the blood brain barrier. Sorry but can't remember the reference right now that compared the various ais and whether they can crossed the blood brain barrier.

 

[schultz]

Ray has mentioned this before.

 

[haidut]

New research suggests the conversion of testosterone to estrogen in the brain is crucial for male sexual desire

Not one, but two, human studies beg to disagree.
Male Sexual Function Does NOT Require Estrogen

Also, did you read the actual article or the study itself? It actually says right in the abstract that estrogen is partially required. Yet, when you read the actual study it says that the mice without aromatase (and thus estrogen) had the same sexual performance as intact mice, but were less interested in engaging in sex. It matches the findings of the human studies above, both of which found slightly reduced desire to engage in sex but no difference in performance. As such, the titles of both the popular press article and the study itself are plain wrong. Both the human studies above and the one you linked to show that estrogen has no role in actual sexual performance/function. It may a have partial role in sexual interest. However, how do you measure optimal level of sexual interest?? There is no standard as to how often one should want sex. There is only a standard as to actual performance of the sex act. Wanting sex all the time (without actual stimulation such as the presence of a naked and willing partner) is NOT a measure of health, but quite the opposite. It is a sign of elevated stress hormones and possibly low dopamine, especially in females. Constant, unprovoked, sexual desire is not much different than the "addiction" of an alcoholic or a drug user.
Brain Aromatase and the Regulation of Sexual Activity in Male Mice
"...Interestingly, the average mount length or intromission length was not different in intact bArKO mice compared with controls (Fig. 2B). The average mount latency, a measure of the average time to initiate the first mount, was approximately 2-fold higher in intact bArKO mice compared with controls (P < 0.05; Fig. 2C). There was a trend (P = 0.059) toward longer intromission latency in bArKO mice versus controls. Overall, intact bArKO mice spent less total time engaged in sexual behaviors such as mounting or intromission (Fig. 2D and more details in Supplemental Movies 1 and 2, available in an online data repository (47)). Taken together, these data suggest that while there was no difference in the qualitative acts associated with sexual behavior in intact bArKO and control mice, intact bArKO mice initiated these behaviors significantly less frequently."

@DennisX @JoeKool @schultz

 

[JoeKool]

Well, I only mentioned libido which is the desire, not the functionality as I was always able to perform when using Ai but noticeably less desire to do so, which you said too:

Both the human studies above and the one you linked to show that estrogen has no role in actual sexual performance/function. It may a have partial role in sexual interest.

Also, one of the side effects of a prolactin inhibitor like Pramipexole is desire to gamble & compulsive activity like masturbation, which is high dopamine. Others report sex drive / libido through the roof too on those. But yes, definitely something that can be addictive like you listed, alcohol or drugs, even the dopamine hit from scrolling through Facebook or Instagram feeds.

But you said low dopamine, which I would've bet the opposite for sex drive.

Have you ever used Letrozole? Is there another avenue to explain the libido killing properties of something as potent at Letro?

 

[haidut]

But you said low dopamine, which I would've bet the opposite for sex drive.

Compulsive behavior is not usually driven by a healthy desire, it is more often driven by an urge to relieve stress. Gambling, drinking, excessive masturbation and stress in general are associated with low-dopamine instead of high. So, I am beginning to suspect that pramipexole has some stress promoting effects and this may be why Peat thinks it is not safe to try.
Stress Leads To Lower Dopamine And More Drinking

Pedophiles are known to have high prolactin and cortisol, they are often the exact opposite of what the popular press presents them as - sex-hungry masculine machines running around in high libido. It's more like under-sexed machines running around in high stress and frustration, attacking children because they cannot actually copulate with an adult woman. Epstein and Weinstein were known to more often masturbate in front of women instead of having sex with them. I think @Drareg talked about that, at least in regards to Weinstein's behavior, in one of his recent posts.

 

[outtherebrother]

Not one, but two, human studies beg to disagree.
Male Sexual Function Does NOT Require Estrogen

Also, did you read the actual article or the study itself? It actually says right in the abstract that estrogen is partially required. Yet, when you read the actual study it says that the mice without aromatase (and thus estrogen) had the same sexual performance as intact mice, but were less interested in engaging in sex. It matches the findings of the human studies above, both of which found slightly reduced desire to engage in sex but no difference in performance. As such, the titles of both the popular press article and the study itself are plain wrong. Both the human studies above and the one you linked to show that estrogen has no role in actual sexual performance/function. It may a have partial role in sexual interest. However, how do you measure optimal level of sexual interest?? There is no standard as to how often one should want sex. There is only a standard as to actual performance of the sex act. Wanting sex all the time (without actual stimulation such as the presence of a naked and willing partner) is NOT a measure of health, but quite the opposite. It is a sign of elevated stress hormones and possibly low dopamine, especially in females. Constant, unprovoked, sexual desire is not much different than the "addiction" of an alcoholic or a drug user.
Brain Aromatase and the Regulation of Sexual Activity in Male Mice
"...Interestingly, the average mount length or intromission length was not different in intact bArKO mice compared with controls (Fig. 2B). The average mount latency, a measure of the average time to initiate the first mount, was approximately 2-fold higher in intact bArKO mice compared with controls (P < 0.05; Fig. 2C). There was a trend (P = 0.059) toward longer intromission latency in bArKO mice versus controls. Overall, intact bArKO mice spent less total time engaged in sexual behaviors such as mounting or intromission (Fig. 2D and more details in Supplemental Movies 1 and 2, available in an online data repository (47)). Taken together, these data suggest that while there was no difference in the qualitative acts associated with sexual behavior in intact bArKO and control mice, intact bArKO mice initiated these behaviors significantly less frequently."

@DennisX @JoeKool @schultz

This is the abstract of the paper you posted "Brain Aromatase and the Regulation of Sexual Activity in Male Mice" (Brain Aromatase and the Regulation of Sexual Activity in Male Mice).

The biologically active estrogen estradiol has important roles in adult brain physiology and sexual behavior. A single gene, Cyp19a1, encodes aromatase, the enzyme that catalyzes the conversion of testosterone to estradiol in the testis and brain of male mice. Estradiol formation was shown to regulate sexual activity in various species, but the relative contributions to sexual behavior of estrogen that arises in the brain versus from the gonads remained unclear. To determine the role of brain aromatase in regulating male sexual activity, we generated a brain-specific aromatase knockout (bArKO) mouse. A newly generated whole-body total aromatase knockout mouse of the same genetic background served as a positive control. Here we demonstrate that local aromatase expression and estrogen production in the brain is partially required for male sexual behavior and sex hormone homeostasis. Male bArKO mice exhibited decreased sexual activity in the presence of strikingly elevated circulating testosterone. In castrated adult bArKO mice, administration of testosterone only partially restored sexual behavior; full sexual behavior, however, was achieved only when both estradiol and testosterone were administered together. Thus, aromatase in the brain is, in part, necessary for testosterone-dependent male sexual activity. We also found that brain aromatase is required for negative feedback regulation of circulating testosterone of testicular origin. Our findings suggest testosterone activates male sexual behavior in part via conversion to estradiol in the brain. These studies provide foundational evidence that sexual behavior may be modified through inhibition or enhancement of brain aromatase enzyme activity and/or utilization of selective estrogen receptor modulators.

Did you read the abstract? Or did you selectively quote a portion within the paper that agrees with your opinions?

 

[TheBeard]

Compulsive behavior is not usually driven by a healthy desire, it is more often driven by an urge to relieve stress. Gambling, drinking, excessive masturbation and stress in general are associated with low-dopamine instead of high. So, I am beginning to suspect that pramipexole has some stress promoting effects and this may be why Peat thinks it is not safe to try.
Stress Leads To Lower Dopamine And More Drinking

Pedophiles are known to have high prolactin and cortisol, they are often the exact opposite of what the popular press presents them as - sex-hungry masculine machines running around in high libido. It's more like under-sexed machines running around in high stress and frustration, attacking children because they cannot actually copulate with an adult woman. Epstein and Weinstein were known to more often masturbate in front of women instead of having sex with them. I think @Drareg talked about that, at least in regards to Weinstein's behavior, in one of his recent posts.

I almost agree with you, except:

1) when I knock out my estrogens with Exemestane, I don't have any healthy sexual desire, let alone pulsions. No random sexual thoughts or erections even.

2) Epstein's face looked very masculine, how could this be achieved with high prolactin and high cortisol?

 

[haidut]

This is the abstract of the paper you posted "Brain Aromatase and the Regulation of Sexual Activity in Male Mice" (Brain Aromatase and the Regulation of Sexual Activity in Male Mice).

The biologically active estrogen estradiol has important roles in adult brain physiology and sexual behavior. A single gene, Cyp19a1, encodes aromatase, the enzyme that catalyzes the conversion of testosterone to estradiol in the testis and brain of male mice. Estradiol formation was shown to regulate sexual activity in various species, but the relative contributions to sexual behavior of estrogen that arises in the brain versus from the gonads remained unclear. To determine the role of brain aromatase in regulating male sexual activity, we generated a brain-specific aromatase knockout (bArKO) mouse. A newly generated whole-body total aromatase knockout mouse of the same genetic background served as a positive control. Here we demonstrate that local aromatase expression and estrogen production in the brain is partially required for male sexual behavior and sex hormone homeostasis. Male bArKO mice exhibited decreased sexual activity in the presence of strikingly elevated circulating testosterone. In castrated adult bArKO mice, administration of testosterone only partially restored sexual behavior; full sexual behavior, however, was achieved only when both estradiol and testosterone were administered together. Thus, aromatase in the brain is, in part, necessary for testosterone-dependent male sexual activity. We also found that brain aromatase is required for negative feedback regulation of circulating testosterone of testicular origin. Our findings suggest testosterone activates male sexual behavior in part via conversion to estradiol in the brain. These studies provide foundational evidence that sexual behavior may be modified through inhibition or enhancement of brain aromatase enzyme activity and/or utilization of selective estrogen receptor modulators.

Did you read the abstract? Or did you selectively quote a portion within the paper that agrees with your opinions?

Sure, I did read the abstract...and the actual study.

As I mentioned in my post, the abstract says that estrogen is "...partially required for male sexual behavior". So, at best, partially required. Yet the popular press article just says "required". If it was absolutely required, then T supplementation should have had NO restorative effect, yet it "...partially restored sexual behavior". The definition of required is something without which the described concept (in this case sexual function) cannot occur at all. Yet, in this study, estrogen was NOT required at all for sexual performance, and only partially required for sexual interest/desire.

More importantly, the actual study text describes that they were talking about sexual interest/desire, not sexual performance. Both the estrogen deficient and non-deficient groups had equal sexual performance. So, the title of both the study and the popular press article should have been "Estrogen partially required for male sexual desire/interest, not required for actual sexual performance". I am not even sure if calling something "partially required" is correct semantically. Something can only be either required or non-required. No partial state possible. A more accurate way of phrasing would have been "Estrogen important for full sexual interest/desire, but not required for either desire or performance".

What part of that is selectively taking portions that confirm my point? If the actual text describing the results of the experiment contradicts what the abstract says, which one do you think takes precedence - the summarizing abstract or the actual experimental results of the paper?

Even if you don't like what I quoted from the mouse study, it is hard to argue with not one but two human studies, demonstrating estrogen is not at all required for male sexual performance, and the actual studies were even titled that way.

 

[haidut]

I almost agree with you, except:

1) when I knock out my estrogens with Exemestane, I don't have any healthy sexual desire, let alone pulsions. No random sexual thoughts or erections even.

2) Epstein's face looked very masculine, how could this be achieved with high prolactin and high cortisol?

Was this lack of desire also in the presence of sexual stimulation? Did it affect performance? I am asking because the "desire" by itself is hard to quantify and describe what should be a healthy level of. Technically speaking, there should not really be a prolonged desire without a stimulus.
Yes, Epstein was known to actually have sex with the girls while Weinstein was mostly masturbating. That's why I focused on Weinstein in my post. But being a pedophile, Epstein was probably in some sort of compromised health and his looks may have been due to steroid use or some other androgenic therapy.

 

[outtherebrother]

Sure, I did read the abstract...and the actual study.

As I mentioned in my post, the abstract says that estrogen is "...partially required for male sexual behavior". So, at best, partially required. Yet the popular press article just says "required". If it was absolutely required, then T supplementation should have had NO restorative effect, yet it "...partially restored sexual behavior". The definition of required is something without which the described concept (in this case sexual function) cannot occur at all. Yet, in this study, estrogen was NOT required at all for sexual performance, and only partially required for sexual interest/desire.

More importantly, the actual study text describes that they were talking about sexual interest/desire, not sexual performance. Both the estrogen deficient and non-deficient groups had equal sexual performance. So, the title of both the study and the popular press article should have been "Estrogen partially required for male sexual desire/interest, not required for actual sexual performance". I am not even sure if calling something "partially required" is correct semantically. Something can only be either required or non-required. No partial state possible. A more accurate way of phrasing would have been "Estrogen important for full sexual interest/desire, but not required for either desire or performance".

What part of that is selectively taking portions that confirm my point? If the actual text describing the results of the experiment contradicts what the abstract says, which one do you think takes precedence - the summarizing abstract or the actual experimental results of the paper?

Even if you don't like what I quoted from the mouse study, it is hard to argue with not one but two human studies, demonstrating estrogen is not at all required for male sexual performance, and the actual studies were even titled that way.

It isn't that I don't like what you stated, we are discussing two concepts here sexual desire and performance. OP stated a study that discuss sexual desire being linked to estrogen, yet you posted studies talking about sexual performance not being influenced by estrogen. The way I see it is that we agree, however your interpretation of the language used, you suggest "partially required" to be a weak statement. However when you look at the data:

On the left column of figures (A-D), brain aromatase deficient mice (bArKO) have statistically significantly less events of sex, higher latency between sex and lower total time of sex. Your semantical interpretation of "somewhat required" being a weak indicator is clearly not supported by this data. In the right column of the figure (E-H), if we look at total body aromatase deficient mice (TArKO), the number of sexual events for homozygous (tArKO) deficient mice is 0, the mice had absolutely 0 desire for sex because of their lack of aromatase enzyme. The heterozygous knockout of aromatase (Het) also had significant effects on desire for sex as seen in the lower # of sexual events, lower time per event, and latency per event.

If we focus on the data this study provides, and not attempt to "semantically" analyze the language used, we can derive better conclusions than what you came to. In conclusion, a deficiency of aromatase in the brain and the whole body clearly has effects on # of sexual events, time per event, and latency between events.

 

[TheBeard]

Was this lack of desire also in the presence of sexual stimulation? Did it affect performance? I am asking because the "desire" by itself is hard to quantify and describe what should be a healthy level of. Technically speaking, there should not really be a prolonged desire without a stimulus.
Yes, Epstein was known to actually have sex with the girls while Weinstein was mostly masturbating. That's why I focused on Weinstein in my post. But being a pedophile, Epstein was probably in some sort of compromised health and his looks may have been due to steroid use or some other androgenic therapy.

I know what a manic estrogen-driven desire feels like, I've experienced it in the past.
I'm not asking to feel this, just asking for a healthy moderate desire that arises when needed.
On Exemestane there was no desire even during the act, like the brain-penis axis was broken.

 

[haidut]

has effects on # of sexual events, time per event, and latency between events

All of those are metrics of desire. I did agree that estrogen is partially involved in sexual desire, as the abstract itself states. Unfortunately, the popular press article talks about estrogen being crucial for sexual "behavior" and behavior to most people means performance - i.e. they are commonly used to mean the same thing in language.
"...Scientists have uncovered an enzyme that appears to play a key role in regulating sexual behavior in males. Their new research, published in the journal Endocrinology, found that selectively disrupting the enzyme aromatase in the brains of male mice led to a sharp decrease in sexual behavior."
Synonyms of behavior | Thesaurus.com

I am not a native English speaker, so maybe I am reading too much into this, but when I read the popular press article this is the overall message I got - i.e. lower your estrogen and your sex life will suffer.
Aside from that problem of semantics, my other other problem with studies like that is that decrease in sexual desire is not based on any standard. What is "optimal" sexual desire? Is it wanting it all the time, once daily, once every other day, only when provoked, etc? So, the popular press article is worded to suggest that estrogen is crucial for male sexual health, when all the study showed is a reduction in sexual interest. That matches the findings of the human studies I referenced but those human studies did not get complaints from the men that their sexual lives were negatively affected. What if low estrogen leads to a state where sexual activity occurs only when stimulated? Is that good or bad? Is the 50% decrease in sexual desire the study found a good or a bad thing? There is no standard based on which one can judge those changes.

Btw, the study I posted is the study the popular press article discusses. It is not an arbitrary study I dug up.
Brain Aromatase and the Regulation of Sexual Activity in Male Mice

 

[haidut]

On Exemestane there was no desire even during the act, like the brain-penis axis was broken.

How much were you taking? I think all AI drugs in higher doses affect the upstream steroids like pregnenolone/progesterone. There are several reports on this forum and also on bodybuilding websites that adding pregnenolone, or pregnenolone/DHEA, or progesterone, or progesterone/DHEA resolves the sexual desire issues despite the very low estrogen levels as a result of the AI drug. Despite the claims of pharma companies, I don't know of any AI drug that is selective only for the aromatase enzyme. They are all "promiscuous", similarly to the drug finasteride that is now known to be a lot more than a "selective" 5-AR inhibitor.

 

[TheBeard]

How much were you taking? I think all AI drugs in higher doses affect the upstream steroids like pregnenolone/progesterone. There are several reports on this forum and also on bodybuilding websites that adding pregnenolone, or pregnenolone/DHEA, or progesterone, or progesterone/DHEA resolves the sexual desire issues despite the very low estrogen levels as a result of the AI drug. Despite the claims of pharma companies, I don't know of any AI drug that is selective only for the aromatase enzyme. They are all "promiscuous", similarly to the drug finasteride that is now known to be a lot more than a "selective" 5-AR inhibitor.

A lot, somewhere around 12.5mg every 2 days.
I never took it in conjunction with Preg, Prog or DHEA.
However, none of these steroids taken in isolation does anything for my libido.

 

[haidut]

A lot, somewhere around 12.5mg every 2 days.
I never took it in conjunction with Preg, Prog or DHEA.
However, none of these steroids taken in isolation does anything for my libido.

That is a high dose. Human studies showed that taking more than 5mg-6mg EXE daily does not depress estrogen levels further but the higher the dose the more likely it is to affect other pathways. Also, the half-life of EXE is around 1-2 days, so taking every day builds it up.
The preg/prog/DHEA may not have an effect by themselves but they may prevent the negative effects of EXE if it does indeed affect those pathways. There is a study I posted recently showing pregnenolone prevents the suppression effects of testosterone/nandrolone on endogenous steroid production but the pregnenolone by itself had almost no effects on any endocrine pathways.

 

[Drareg]

Compulsive behavior is not usually driven by a healthy desire, it is more often driven by an urge to relieve stress. Gambling, drinking, excessive masturbation and stress in general are associated with low-dopamine instead of high. So, I am beginning to suspect that pramipexole has some stress promoting effects and this may be why Peat thinks it is not safe to try.
Stress Leads To Lower Dopamine And More Drinking

Pedophiles are known to have high prolactin and cortisol, they are often the exact opposite of what the popular press presents them as - sex-hungry masculine machines running around in high libido. It's more like under-sexed machines running around in high stress and frustration, attacking children because they cannot actually copulate with an adult woman. Epstein and Weinstein were known to more often masturbate in front of women instead of having sex with them. I think @Drareg talked about that, at least in regards to Weinstein's behavior, in one of his recent posts.

My guess is -
It’s a pathological incoherent sex drive, perceived taboos and depravity to get aroused, even this state of arousal is somewhat flaccid because it’s driven more by stress hormones.
It’s a survival mode sex drive. It’s an energy disorder underlying it all, an extremely attractive grown woman is maximizing her energy levels, it’s becomes a stressor for some men to match her energy levels, her general tissue capacitance has a higher capacity to maintain energy ,basically what stress is -something in the environment requires you to expend energy to overcome/resolve/solve/match and connect with it. The woman in question signals greater fitness and she selects males that can match it for the most part.
Depravity is a form of lowering energy in another which brings the victim to the energetic level of the abuser even if it’s only temporary.

A child as metabolically coherent as they are must still develop the growth to maximize energy capacitance in all tissues and organs therefore they are weaker than most adults, even adults in a low energy state like paedophiles have more general energy capacitance hence their predatory behavior toward kids and not more coherently energetic adults ,obviously some tissues within a paedophile have less capacity for energetic storage like the prefrontal cortex, a child’s prefrontal cortex is still developing, the paedophile construes this similarity as attraction when in reality it’s "dysfunction" and rigidity of the adult brain, pathological, it’s also the predator knowing/sensing the most powerful aspect of the brain in a child is not formed yet and acting in a predatory manner.
It almost like the paedophile is hijacking the preferred process of coherent energy and symmetry in its early stages because once fully grown the paedophiles are rejected and overpowered, it’s predatory without question.

 

[Broken man]

I am with this with @haidut, I have borderline high estrogen, higher than midrange of prolactin. I was very moody and constantly seeking for dopamine related activities like constant urge to masturbate, playing computer games, naked photos and so on.... After starting with ladasten, high dose taurine (6g) and some probiotics, it normalized little bit. I am now other person, I quit playing computer games, started helping my father with our farm and teaching my little brother chemistry .....