Growth-suppressing chemicals in hair follicles

[cyberprimate]

Bryan wrote "Androgens cause the dermal papillae of scalp hair follicles to secrete various growth-suppressing chemicals which then adversely affect the health of the rest of the follicle."

What chemicals are these? And where can i find a study that showed the existence of these chemicals?

 

[DarkDays]

Sounds like it would only require to eliminate androgens or counter these chemicals.

However, I've seen people who have eliminated most(if not all) androgens in their body(T as well as DHT) and have experienced very limited regrowth. Some even continue experiencing hairloss.

 

[DarkDays]

Sounds like it would only require to eliminate androgens or counter these chemicals.

However, I've seen people who have eliminated most(if not all) androgens in their body(T as well as DHT) and have experienced very limited regrowth. Some even continue experiencing hairloss.

Hey DarkDays...really interested in that info.....did they do anything about the 5AR or just try to eliminate the hormones?

I am talking about transgender people who are on HRT(Like myself). Last time I had a bloodtest(2 weeks ago) I had 0 testosterone(can't be measured it was so low) and estrogen through the roof(need to adjust my dosage and lower my levels a bit), and even though I am getting some regrowth, the hair is still thin in the top area and the temples haven't started to regrow(yet a lot of vellus hairs there).

This is why I think that although androgens can play a role, balding/thinning process involves something more.

On a related note, trans men(female to male transsexuals) tend to become bald one and all at some point or another. Yet it doesn't happen outright. It doesn't start until much later when the testosterone has actually affected their bone structure to some extent.
At one point I considered the skull expansion as one thing you can notice in older transmen is that their skulls are much bigger than before they started transitioning. So regardless of whether skull expansion affects the balding process(no literature on that except this one guy selling that e-book), skulls can expand given the right hormones in the system. You just need to look at athletes who have used steroids. They are sometimes called steroid heads because their skulls expand in a weird manner.

As an example of how much testosterone can affect. Here is a transition collage of a transguy http://i.imgur.com/WeyUO.jpg

 

[Sebastien]

wait


















































wat










that girl became that man?

 

[keepinthehair]

Regrowth would not be expected due to a lack of T/DHT as the follicles are obviously already dead or "inactive."

It's interesting that the "female" transgenders would begin male pattern baldness with the introduction of T as this demonstrates they carry the dominant DHT sensitive follice (requiring only one copy to bald) and the same follicle is recessive to Estrogen (requires two copies).

 

[Bryan]

Bryan wrote "Androgens cause the dermal papillae of scalp hair follicles to secrete various growth-suppressing chemicals which then adversely affect the health of the rest of the follicle."

What chemicals are these? And where can i find a study that showed the existence of these chemicals?

An obvious example would be TGF-beta 1 and 2. There are probably numerous other such chemicals, and identifying them is an area of current research. See the abstract below.

Eur J Dermatol. 2001 Jul-Aug;11(4):315-20.

"Do androgens influence hair growth by altering the paracrine factors secreted by dermal papilla cells?"
Randall VA, Hibberts NA, Thornton MJ, Merrick AE, Hamada K, Kato S, Jenner TJ, de Oliveira I, Messenger AG.

Department of Biomedical Sciences, University of Bradford, Bradford, BD7 1DP, UK.

Abstract
Androgens regulate many aspects of human hair growth in both sexes. After puberty they transform tiny vellus follicles in many areas, e.g. the face, to terminal ones producing long, thick, pigmented hairs. In genetically predisposed individuals, androgens also cause the reverse transformation of terminal scalp follicles into vellus ones, causing balding. In the current hypothesis for androgen action, androgens control most follicular cells indirectly acting via the mesenchyme-derived dermal papilla which regulates many aspects of follicular activity. In this model androgens binding to androgen receptors in dermal papilla cells alter their production of regulatory molecules which influence other follicular components; these molecules may be soluble paracrine factors and/or extracellular matrix proteins. This hypothesis is supported by immunohistochemical localisation of androgen receptors in dermal papilla cell nuclei and the demonstrations that androgen receptor content and testosterone metabolism patterns of cultured dermal papilla cells from various body sites reflect hair growth in androgen-insensitivity syndromes. The next question is whether androgens alter the paracrine factors secreted by dermal papilla cells. Cultured dermal papilla cells do release soluble, proteinaceous factors into their media which stimulate the growth of keratinocytes and other dermal papilla cells. This mitogenic potential can cross species from humans to rodents. Importantly, testosterone in vitro stimulates the mitogenic potential of beard cells, but in contrast inhibits production by balding scalp cells reflecting their in vivo androgenic responses. Since androgens in vitro do alter the secretion of paracrine factors the current focus lies in identifying specific factors produced, e.g. IGF-I and stem cell factor (SCF), using ELISA and RT-PCR, and comparing their expression in cells from follicles with varying responses to androgens in vivo or under androgen stimulation in vitro. This should lead to greater understanding of androgen action and enable the development of better treatment for androgen-potentiated disorders.

 

[Bryan]

Sounds like it would only require to eliminate androgens or counter these chemicals.

However, I've seen people who have eliminated most(if not all) androgens in their body(T as well as DHT) and have experienced very limited regrowth. Some even continue experiencing hairloss.

HUH?? It should be common knowledge among everybody (it's basically Hairloss 101) that simply removing androgens doesn't cause much scalp hair regrowth. This is something that's been discussed for years and years and years, my friend.

 

[freakout]

NO regrowth to some, regrowth to others and continued hairloss to others.

YET when hair follicles are transplanted onto mice, they grow like hell even better than terminal hair!!!

Something is amiss in 'androgenetics'. It's a theory!

 

[Bryan]

YET when hair follicles are transplanted onto mice, they grow like hell even better than terminal hair!!!

Uhhh....that only happened in ONE such experiment, not in the others. If I were you, I wouldn't go off the deep end because of just ONE small experiment! :smack:

Something is amiss in 'androgenetics'. It's a theory!

Why, OF COURSE it's just a theory! Everybody knows what really causes it is the phase of the moon!! :laugh:

 

[freakout]

One experiment?

That's 28 men and 11 women. And then they had to repeat it with two more men to check with some more varaibles. That's two experiments.

What do you know, same results!

Scalp hair follicles DO NOT respond directly to androgens.

 

[Bryan]

Scalp hair follicles DO NOT respond directly to androgens.

OH REALLY??? How do you explain the in vitro experiments that showed the growth suppression of scalp hair follicles from androgens?? :laugh:

 

[freakout]

Where?

 

[Bryan]

Where?

Well, just one example would be the following study: "RNA-levels of 5a-reductase and androgen receptor in human skin, hair follicles and follicle-derived cells". W. Eicheler, A. Huth, R. Happle and R. Hoffmann. From the book "Hair Research for the Next Millenium", copyright 1996 Elsevier Science. D.J.J. Van Neste and V.A. Randall (Eds).

I can't type-out the whole study for you, but here's just a small sample, indicating that you need to start doing some serious research before making preposterous claims like "scalp hair follicles DO NOT respond directly to androgens". That's a really stupid thing to say!

"...With respect to the in vitro growth, two types of hair follicles were identified; androgen-sensitive follicles showed a dose-dependent inhibition of length growth by testosterone (Figs. 1a and 1c), whereas in androgen-insensitive follicles no effect of testosterone was observed (Fig. 1b). Both types of follicles were found in male and female donors aged between 15 and 51 years. Also, in hair follicles of the occipital scalp, androgen sensitive as well as androgen insensitive follicles were found..."

 

[Bryan]

Below is part of another post I made several years ago, which documents a fascinating in vitro study by Sawaya of the effects of RU58841 on human hair follicles (both beard and scalp). Once again, I laugh at freakout's ridiculous claim that hair follicles aren't directly affected by androgens:

I have some test study questions Im sure someone can answer........

1.> Have in vitro test been performed to see if body hair responds to DHT directly?

Hmmm.... I'm sure there's a number of them around, but here's an interesting one (albeit somewhat INDIRECT, because the main purpose of it was to test the effects of RU58841 on both scalp hair and body hair): "RU58841, a new therapeutic agent affecting androgen receptor molecular interactions in human hair follicles", M.E. Sawaya, from the book "Hair Research for the Next Millenium", 1996. Here's a fascinating excerpt from this study, showing the differential effects of antiandrogens (and, by extension, androgens themselves) on body hair and beard hair (emphasis added is my own):

"...The study of beard and scalp hair follicles of 6 male donors in longer term culture (up to 14 days) appeared to be an interesting model. The whole follicles were mounted in a collagen matrix. The study revealed significant differences (p<0.005) when the follicles were cultured in DHT (10 nM and 100 nM) in the absence or presence of 1 uM RU58841 added, i.e.:

a) in the presence of RU58841 hair follicle growth rates were found to be increased by 23% for scalp follicles but a 16% decrease was noted in beard follicles.

b) protein, DNA, and RNA polymerase II activity revealed increases in scalp (25%, 12%, and 12% respectively) and respectively equivalent relative decreases in beard hair follicles.

c) thioredoxin reductase activity, a sulfhydryl-reducing enzyme important for keratin protein synthesis, increased by 16% in scalp follicles after 14 days in culture but decreased by 10% in beard hair follicles."

Isn't that really cool?? :lol: Stephen Foote always used to bug me to explain the EXACT ways that androgens affect hair follicles, and above are some examples of the specific ways that androgens (and antiandrogens) have differential effects on scalp hair follicles and body hair follicles.

At the end of the study in the Conclusion section, Sawaya goes on to say: "The model system using human hair follicles from scalp and beard in a 14 days culture system is a novel approach in testing drugs and compounds for their effectiveness in stimulating scalp or inhibiting beard hair growth....other ongoing studies using animal models such as the teady bear hamster, mouse androgenetic alopecia model, and macaque monkey and other human models (see elsewhere in this volume) revealed similar findings with regard to RU58841."

 

[Bryan]

One experiment?

That's 28 men and 11 women. And then they had to repeat it with two more men to check with some more varaibles. That's two experiments.

What do you know, same results!

What study are you referring to? The Krajcik et al study you refer to in your signature file? They used exactly THREE humans in that study: a couple of men, and one woman. You seem very very confused by all this stuff! :smack:

 

[freakout]

Transplants from balding and hairy androgenetic
alopecia scalp regrow hair comparably well on
immunodeficient mice

Rozlyn A. Krajcik, PhD, Joseph H. Vogelman, DEE, Virginia L. Malloy, MS, and Norman Orentreich, MD

DISCUSSION:

The original intent of this study was to optimize the procedure of grafting human hair follicles onto immunodeficient mice to have a highly reproducible model system for evaluating treatments for Androgenetic Alopecia. Tothat end, various methods of transplantation were compared (data not shown), as were several strains of mice both male and female, and scalp skin from balding and hairy regions of numerous Androgenetic Alopecia male and female donors (28 males; 11 females).

What became apparent, contrary to the results reported by Van Neste et al,6 was that regardless of the method used and sex or strain of mice, grafts from balding scalp produced pigmented terminal hairs equal in length and diameter to those produced by transplanted hair follicles from hairy, nonbalding scalp.

We report here the results from 2 representative male donors in an experiment using female nude mice.
---------------------

Krajcik was too kind to use the word 'contrary'. If I were him, I'd call Van Neste a liar.

Me confused? I like to make things simple: Scalp hair follicles DO NOT respond directly to male hormones.

 

[freakout]

That study is a fact. Androgenetics is a belief that finasteride salesmen are required to push.

Krajcik was too kind to use the word 'contrary'. If I were him, I'd call Van Neste a liar.

 

[hairhoper]

:jackit:

Can we stop feeding this freakout troll please. He's clearly deluded or has some other agenda. Either way he can't be convinced of the obvious truth so we should probably save our collective breath.

 

[freakout]

Thank you. Sounds like Krajcik, PhD, Joseph H. Vogelman, DEE, Virginia L. Malloy, MS, and Norman Orentreich, MD, were deluded as well when they said 'contrary to the results reported by Van Neste'.

I'd like to hear your comment on the Krajcik study if you have any.

I'm not discounting the involvemnt of androgens. I'm only questioning the DIRECT involvement. Expand your horizons.

Thanks!

deluded freakout.
------------------------------
Sorry, cyberprimate, for messing up your thread! I can't help it when some people are trying their best to put people inside the Androgenetic Alopecia box.

Krajcik did mention the possibility of other biochemicals in the mouse study like neuropeptides and cytokine. But these are equally present in women.

I'm out.

 

[cyberprimate]

Sorry, cyberprimate, for messing up your thread!

No problem. I've already had my answer.