Is a myth that eunuchs dont lose the hair?

[Thom]

It is true, Native Americans...North Americans at least do not lose their hair. If you see one who is balding, it is due to his part-European (or Old World) ancestry. Every full-blood, or close to full-blood Native I've ever known retained every bit of their hair. I wish my Native American genes showed up in the form of great hair, unfortunately I just got the genes that made me an alcoholic lightweight! :woot:

 

[Bryan]

I'm not saying they are the only hormones involved, but circulating hormones do have an impact on hair growth. You make quite a bold statement for things even Scientists don't truly understand. We know that testosterone therapy has an impact on plasma lipoprotein profile. We know that injecting subcutaneous testosterone results in hair growth. In fact there are numerous studies promoting testosterone's hair growing abilities. It's speculated that with balding men the tissues in the region affected by hair loss converts the testosterone to DHT and testosterone stops having its effect on the hair growth. Hell, here's a study that shows testosterone injections increasing hair growth for women at the scalp. [snip study]

There's even an early study by Dr. Albert M. Kligman MD, PhD (the most famous name in the history of dermatology) back in the 1960s, which claimed that hair growth could even be stimulated to grow in balding men by the topical application of testosterone. That theory was refuted a year or two later by some other doctors, who tested it very thoroughly and carefully. Even Kligman, of all people, can occasionally have a bad day at the office!

 

[kehcorpz]

There's even an early study by Dr. Albert M. Kligman MD, PhD (the most famous name in the history of dermatology) back in the 1960s, which claimed that hair growth could even be stimulated to grow in balding men by the topical application of testosterone. That theory was refuted a year or two later by some other doctors, who tested it very thoroughly and carefully. Even Kligman, of all people, can occasionally have a bad day at the office!

Hehe nice. Except, 5-ar-2 enzyme is generated directly in the scalp tissue and it would have the same effect on exogenous testosterone as endogenous serum testosterone entering the scalp tissue. Ahh the complexities of science, so much we do not understand, but I guess that's the beauty of science.

 

[Bryan]

...5-ar-2 enzyme is generated directly in the scalp tissue...

To be a bit more specific, the 5a-reductase type 2 enzyme is generated inside the dermal papillae of hair follicles.

 

[kehcorpz]

To be a bit more specific, the 5a-reductase type 2 enzyme is generated inside the dermal papillae of hair follicles.

Hehe fair enough, and also in the sebaceous ducts


It's also why I don't use Nizoral because I think it's useless. Unless of course there's evidence to suggest it blocks 5-ar-2. I used to use it but I went off it with no hair issues, in fact my hair has improved since it had a drying effect.

 

[Bryan]

Hehe fair enough, and also in the sebaceous ducts

What's your source for thinking that 5a-reductase type 2 is made in sebaceous ducts?

It's also why I don't use Nizoral because I think it's useless. Unless of course there's evidence to suggest it blocks 5-ar-2. I used to use it but I went off it with no hair issues, in fact my hair has improved since it had a drying effect.

Why do you think it would be useless unless it "blocks" 5a-reductase type 2? Ketoconazole is known to have antiandrogenic properties.

 

[kehcorpz]

What's your source for thinking that 5a-reductase type 2 is made in sebaceous ducts?

Well, it's something I remember from books, but you can google it. Here's one from pubmed that shows activity of the enzyme in particular regions.

Activity of type 1 5 alpha-reductase is greater in the follicular infrainfundibulum compared with the epidermis.
Thiboutot DM, Knaggs H, Gilliland K, Hagari S.
Source

Department of Medicine, Pennsylvania State University College of Medicine, Hershey 17033, USA.
Abstract

The enzyme 5 alpha-reductase converts testosterone (T) to dihydrotestosterone (DHT). Although this enzyme has been localized to various regions of the pilosebaceous unit, its activity has not been studied in the follicular portion of either vellus or sebaceous follicles. The goal of our study was to determine the relative activities of 5 alpha-reductase within various regions of these follicles with particular emphasis on the infrainfundibulum. A finding of increased 5 alpha-reductase activity in upper follicles compared to epidermis might support the hypothesis that increased follicular production of DHT is involved in the hyperkeratinization observed in this region of the follicle in acne vulgaris. 5 alpha-reductase activity was determined at pH 5 (optimal for the type 2 isozyme) and pH 7 (optimal for the type 1 isozyme) in isolated infrainfundibular segments from sebaceous and vellus follicles, homogenized epidermis from various anatomical areas and in microdissected segments of the pilosebaceous unit from breast skin of normal subjects. Enzyme activity was also determined at pH 7 in cultured infrainfundibular keratinocytes and in interfollicular epidermal keratinocytes. Homogenates of infrainfundibular segments demonstrated significantly greater activity at pH 7 compared to pH 5 (P < 0.001), confirming activity of the type 1 5 alpha-reductase in this region. Activity of 5 alpha-reductase was much lower in homogenized epidermis and did not demonstrate a clear pH preference. Keratinocytes cultured from the infrainfundibulum demonstrated significantly greater 5 alpha-reductase activity compared to keratinocytes from interfollicular epidermis (P = 0.04). In the dissected segments of pilosebaceous units from breast skin, 5 alpha-reductase activity was greatest in the sebaceous gland followed by the sebaceous duct, infrainfundibulum, whole skin and epidermis. These data indicate that 5 alpha-reductase activity varies within regions of the pilosebaceous unit and compared with interfollicular epidermal cells, infrainfundibular keratinocytes have an increased capacity for producing androgens which may play a role in the follicular hyperkeratinization seen in acne.

Why do you think it would be useless unless it "blocks" 5a-reductase type 2? Ketoconazole is known to have antiandrogenic properties.

Well, testosterone is an androgen and it's believed it helps hair growth. And we don't even understand the balding process, we simply know somehow DHT is involved and propecia helps it. But yet people who don't have male pattern baldness still have dht in scalp tissue and normal levels of DHT. And when Merck did a study on MK-386 which blocks DHT through 5-alpha-1 even though there was a lowering of DHT it had no impact on hair. Granted it didn't lower it as much as finasteride, but you'd think lowering it even a bit would benefit in some way. The recent Phase 2 study of Dutasteride even shows that both finasteride and dutasteride raise scalp tissue it was something around:

Scalp Testosterone rose 24% for Finasteride, 46% for 0.05mg Dutasteride, 44% for 0.1mg Dutasteride, 104% for 0.5mg Dutasteride, and 154% for 2.5mg Dutasteride.

So if nizoral is an anti-androgen and it lowers testosterone in the scalp, it's POSSIBLE it may be doing more harm than good. And I emphasize possible because no one knows for sure as we do not understand the whole hair loss process. And if testosterone is indeed what helps the hair grow then an anti-androgen won't do any good. Sure it can block DHT if it even does that but it won't stop 5-ar-2 from converting testosterone to DHT before it can do its job. Finasteride isn't really an anti androgen all it does is bind to 5-ar-2, it doesn't care about DHT or testosterone or DHEA or any other androgen.

 

[Bryan]

"What's your source for thinking that 5a-reductase type 2 is made in sebaceous ducts?"

Well, it's something I remember from books, but you can google it. Here's one from pubmed that shows activity of the enzyme in particular regions. [snip study]

They claim in that study that it's mostly the type 1 form which is in the specific areas they mention, and I think they're right about that. I think it's been convincingly established that the type 1 form of 5a-reductase is what's in sebaceous glands.

"Why do you think it would be useless unless it 'blocks' 5a-reductase type 2? Ketoconazole is known to have antiandrogenic properties."

Well, testosterone is an androgen and it's believed it helps hair growth.

Testosterone is absolutely, positively NOT known to "help hair growth"! Testosterone (and other androgens) suppresses the growth of scalp hair!! That's supposed to be the very FIRST thing you learn in Hairloss 101!

And we don't even understand the balding process, we simply know somehow DHT is involved and propecia helps it.

Androgens cause the dermal papilla in scalp hair follicles to release various chemicals (one example of which are the members of the TGF-beta family of hormones) which migrate to the rest of the hair follicle, and then stunt their growth. There have been a number of studies on that very issue.

But yet people who don't have male pattern baldness still have dht in scalp tissue and normal levels of DHT. And when Merck did a study on MK-386 which blocks DHT through 5-alpha-1 even though there was a lowering of DHT it had no impact on hair. Granted it didn't lower it as much as finasteride, but you'd think lowering it even a bit would benefit in some way.

Everybody's scalp hair is sensitive to androgens, but it's a matter of degree: some people's scalp hair is more sensitive to androgens than others. By the way, MK386 doesn't work against male pattern baldness because the form of 5a-reductase in the dermal papillae of hair follicles is the type 2 form. That's why finasteride is what works against male pattern baldness, not MK386.

So if nizoral is an anti-androgen and it lowers testosterone in the scalp, it's POSSIBLE it may be doing more harm than good. And I emphasize possible because no one knows for sure as we do not understand the whole hair loss process. And if testosterone is indeed what helps the hair grow then an anti-androgen won't do any good. Sure it can block DHT if it even does that but it won't stop 5-ar-2 from converting testosterone to DHT before it can do its job. Finasteride isn't really an anti androgen all it does is bind to 5-ar-2, it doesn't care about DHT or testosterone or DHEA or any other androgen.

Antiandrogens given systemically don't "lower" the production of testosterone and other androgens, they RAISE the production of testosterone (unless they also have a direct effect on the chemical mechanism that produces androgens...spironolactone is such an example). But again, I assure you that testosterone doesn't "help grow scalp hair"!!

 

[kehcorpz]

They claim in that study that it's mostly the type 1 form which is in the specific areas they mention, and I think they're right about that. I think it's been convincingly established that the type 1 form of 5a-reductase is what's in sebaceous glands.

You asked to show you. I never claimed all of it was produced there just that there is 5-alpha-reductase 2 produced in the ducts, albeit a small amount.

Site Sex: ages (years) pH 5 pH 7‡


Temple M: 53, 71, 75, 82, 83 0.22/0.22 3.91/3.86

As it got closer to the top of scalp the levels were increased.

Testosterone is absolutely, positively NOT known to "help hair growth"! Testosterone (and other androgens) suppresses the growth of scalp hair!! That's supposed to be the very FIRST thing you learn in Hairloss 101!



Androgens cause the dermal papilla in scalp hair follicles to release various chemicals (one example of which are the members of the TGF-beta family of hormones) which migrate to the rest of the hair follicle, and then stunt their growth. There have been a number of studies on that very issue.



Everybody's scalp hair is sensitive to androgens, but it's a matter of degree: some people's scalp hair is more sensitive to androgens than others. By the way, MK386 doesn't work against male pattern baldness because the form of 5a-reductase in the dermal papillae of hair follicles is the type 2 form. That's why finasteride is what works against male pattern baldness, not MK386.



Antiandrogens given systemically don't "lower" the production of testosterone and other androgens, they RAISE the production of testosterone (unless they also have a direct effect on the chemical mechanism that produces androgens...spironolactone is such an example). But again, I assure you that testosterone doesn't "help grow scalp hair"!!

As with all things in science things are constantly discovered. I showed you the study with the female hair growth as a result of testosterone. And while testosterone has a role in tgf-beta modulation it's primarily _DHT_ that stimulates its synthesis in dermal papilla cells. _DHT_ also inhibits adenil cyclase enzyme which results in the glycolisis stopping and shutting down of the krebs cycle and pentose phosphate shunt and well the hair stops anagen. Next time hair goes into anagen there's even more dht inhibiting adenil cyclase and the anagen cycle decreases in length. In fact part of hair miniaturization is the result of anagen cycle getting shorter and shorter. Testosterone once again on its own will not cause hair loss. This is why scalp tissues of people taking finasteride and Dutasteride show a remarkable increase in testosterone. Some showed scalp tissue testosterone levels rising to __154%__ on 0.5mg of duta. Please explain that one to me if testosterone is implicated in hair loss. The results are regrowth and reversal in miniaturization regardless of testosterone's minimal modulation of TGF-beta.

Role of TGF-beta2 in the human hair cycle.
Hibino T, Nishiyama T.
Source

Shiseido Life Science Research Center, 2-12-1 Fukuura, Kanazawa-ku, Yokohama 236-8643, Japan. toshihiko.hibino@to.shiseido.co.jp
Abstract

Male pattern baldness is the result of premature entry into catagen due to androgens. In order to prevent hair loss, it is important to understand two critical steps, i.e., the induction mechanism of premature entry and the regression process of catagen. At the initiation, dihydrotestosterone (DHT) stimulates synthesis of transforming growth factor-beta2 (TGF-beta2) in dermal papilla cells. TGF-beta2 suppresses proliferation of epithelial cells and stimulates synthesis of certain caspases. Then TGF-beta2 triggers the intrinsic caspase network and subsequently epithelial cells are eliminated through apoptotic cell death. TGF-beta antagonists are effective in preventing catagen-like morphological changes and in promoting elongation of hair follicles in vivo and in vitro. These lines of evidence strongly suggest the presence of a "catagen cascade" in male pattern baldness, involving: (1) the conversion of testosterone to DHT by type II 5-alpha-reductase; (2) the synthesis of TGF-beta2 in dermal papilla cells; and (3) the activation of the intrinsic caspase network. These sequential events contribute to the shortening of the human hair cycle.

Come on man, you should know that. Hair 101.

 

[bigentries]

That video doesn't claim these are bald eunuchs

They probably just shaved their heads, many have noticeable hairline shadows.

Find a eunuch with a grown horseshoe and you might have a point

 

[Bryan]

As with all things in science things are constantly discovered. I showed you the study with the female hair growth as a result of testosterone.

I've never seen any "study" that claimed scalp hair growth as a result of testosterone.

And while testosterone has a role in tgf-beta modulation it's primarily _DHT_ that stimulates its synthesis in dermal papilla cells.

DHT is a more potent androgen than testosterone, which is why it has a stronger role in male pattern baldness than testosterone. Nevertheless, testosterone suppresses the growth of scalp hair just like DHT, although at a much slower rate.

_DHT_ also inhibits adenil cyclase enzyme which results in the glycolisis stopping and shutting down of the krebs cycle and pentose phosphate shunt and well the hair stops anagen. Next time hair goes into anagen there's even more dht inhibiting adenil cyclase and the anagen cycle decreases in length. In fact part of hair miniaturization is the result of anagen cycle getting shorter and shorter. Testosterone once again on its own will not cause hair loss. This is why scalp tissues of people taking finasteride and Dutasteride show a remarkable increase in testosterone. Some showed scalp tissue testosterone levels rising to __154%__ on 0.5mg of duta. Please explain that one to me if testosterone is implicated in hair loss. The results are regrowth and reversal in miniaturization regardless of testosterone's minimal modulation of TGF-beta.

Explain to you why finasteride and dutasteride show an increase in scalp testosterone?? That's because those drugs greatly inhibit the conversion of testosterone into the much stronger DHT. The result is an improvement in male pattern baldness, even though testosterone continues to suppress the growth of scalp hair follicles; it just does so at a much slower rate.

 

[kehcorpz]

I've never seen any "study" that claimed scalp hair growth as a result of testosterone.



DHT is a more potent androgen than testosterone, which is why it has a stronger role in male pattern baldness than testosterone. Nevertheless, testosterone suppresses the growth of scalp hair just like DHT, although at a much slower rate.



Explain to you why finasteride and dutasteride show an increase in scalp testosterone?? That's because those drugs greatly inhibit the conversion of testosterone into the much stronger DHT. The result is an improvement in male pattern baldness, even though testosterone continues to suppress the growth of scalp hair follicles; it just does so at a much slower rate.

Wow you are predictable. I knew you were going to bring up how potent DHT is compared to testosterone. And yes I know that the suppression of DHT is the reason for the increased testosterone, I was asking you why hair reversal occurs if testosterone causes hair loss as you so boldly state. You wouldn't get reversal but simply a slow down of the degradation process. But guess what? The reversal is due to adenil cyclase being available in order to initiated glycolisis. You are only partially right as Testosterone modulates hair growth and will suppress only to _control length_ and other factors but not to induce hair loss. This is in part why men can't grow hair as long as women, in fact estrone is responsible for creating more adenil cyclase and invoking a longer anagen state which women have. Testosterone is in the scalp tissue of _non-balding_ males and will control hair growth. See you clearly show that you have never went to school on these matters and only research online as a result of your infliction. You throw around complex words like TGF-beta and think you automatically understand how it works hah. You obviously do not understand Krebs, glycolisis and pentose phosphate shunt and the enzymes involved in these hair sustaining processes. Testosterone acts as a transcription factor and upon association to the androgen receptor element it modulates transcription and protein synthesis. I'm not stating that you need to inject testosterone in your scalp, but simply making the correlation that testosterone is indeed a positive hormone. And while DHT is WITHOUT A DOUBT 100% involved in suppressing glycolisis. WHAT WE DON'T KNOW IS WHY THE HAIR DIES COMPLETELY AT SOME POINT. Why can't the glycolisis process be restarted once the hair is gone. And all the other stuff is fact, my theory which isn't fact is that testosterone may in some way help re-invoke this process in some of the dead hair. This is all that I speculate that is not fact. Everything else I said is indeed fact. So I'm not going to waste my time with you anymore. And you didn't see the study about testosterone? Yes you did, I guess you have a bad memory. But here it is again.

Br J Dermatol. 2012 Feb;166(2):274-8. doi: 10.1111/j.1365-2133.2011.10655.x. Epub 2012 Jan 9.

Improvement in scalp hair growth in androgen-deficient women treated with testosterone: a questionnaire study.

Glaser RL, Dimitrakakis C, Messenger AG.


Source

Millennium Wellness Center, 228 E. Spring Valley Road, Dayton, OH 45458, USA. rglaser@woh.rr.com


CONCLUSIONS:

Subcutaneous testosterone therapy was found to have a beneficial effect on scalp hair growth in female patients treated for symptoms of androgen deficiency. We propose this is due to an anabolic effect of testosterone on hair growth. The fact that no subject complained of hair loss as a result of treatment casts doubt on the presumed role of testosterone in driving female scalp hair loss. These results need to be confirmed by formal measurements of hair growth.

I guess when I think about it it's kind of pathetic we are doing arm chair science because it's not like we will solve the problem of hair loss.

 

[Bryan]

Over the years, I've seen a number of alternate theories about what causes or contributes to balding; some of them were actually rather amusing. But I'm not going to waste any more of my time trying to argue with somebody who thinks that testosterone, of all things, causes hair to grow!

 

[Armando Jose]

Bryan wrote: "Everybody's scalp hair is sensitive to androgens, but it's a matter of degree: some people's scalp hair is more sensitive to androgens than others."

What is the reason for it? genetics? different hair homeostasis?

 

[Bryan]

What is the reason for it? genetics? different hair homeostasis?

Yes. Genetics.

 

[abcdefg]

Bryan you generally know a lot about research into hair loss. What treatments do you use or what do you think our best choices are right now in terms of preventing hair loss? I still wonder about the long term safety of propecia combined with my hair loss is not that bad and I dont want to turn a minor problem into a major one given our lack of understanding on exactly what else is at play besides just DHT.

- - - Updated - - -

One more thing if we had a perfect treatment to block or interfere with receptors like say CB or RU that just act topically would they prevent hair growth then like facial hair or body hair? I would be curious to see how that would work.

 

[Jacob]

abcdefg..you've been here since 2005 and you need to ask him that? :shock:

 

[abcdefg]

Yeah good point. Maybe I should rephrase that to what are your thoughts on long term safety of propecia and can it help stop a mature hairline? Why would propecia not keep a Norwood 0 if pseudo hermaphradites never get mature hairlines and propecia tightly mimics their hormonal profiles? Im debating trying it to keep my hair but the idea of a drug still scares me.

 

[Jacob]

No lol..I actually meant your first question.

 

[abcdefg]

Testosterone by itself does not cause hairloss. the psudohermaphrodites had normal levels of testosterone and even alpha 5 reducatse 1, and still had no hairloss

That may be true but lets be honest there are a whole **** ton of things going on that we may not know of or have a way of testing. It could be a combination of different things as opposed to just absolute DHT levels. How do we know they have a very low number of androgen receptors or for some reason their hair became insensitive to the effects of androgens? I mean its just kind of a guess that its DHT and we also know testosterone hurts hair.
That being said I think propecia speaks for itself clearly DHT is very important. My personal feeling is some reaction to lowering DHT after you already had normal or high levels causes something such as more receptors that causes more sensitivity which makes propecia either not work or lose effectiveness in some people over time. I guess all the other hormones it indirectly screws with could be part of that also but I still think a more powerful anti androgen such as CB if it pans out, could prevent male pattern baldness forever if started before any hair loss.