A Review of male pattern baldness Research.

[Gone]

Senescent balding and Androgenetic Alopecia are two totally different processes, but they are confused because senescent thinning can make Androgenetic Alopecia more pronounced. Also Androgenetic Alopecia progresses with age but is not itself a result of aging tissues.

 

[Galeaoman]

"Important hormones for hair are not produced in testes but in pilosebaceous unit" . Do you remember Bryan Shelton?

I remember Bryan Shelton, yes, He had much research knowledge with regards to male pattern baldness.

Pilosebaceous units are interesting...


https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835896/

Hormones can exert their actions through endocrine, paracrine, juxtacrine, autocrine and intracrine pathways. The skin, especially the pilosebaceous unit, can be regarded as an endocrine organ meanwhile a target of hormones, because it synthesizes miscellaneous hormones and expresses diverse hormone receptors. Over the past decade, steroid hormones, phospholipid hormones, retinoids and nuclear receptor ligands as well as the so-called stress hormones have been demonstrated to play pivotal roles in controlling the development of pilosebaceous units, lipogenesis of sebaceous glands and hair cycling. Among them, androgen is most extensively studied and of highest clinical significance. Androgen-mediated dermatoses such as acne, androgenetic alopecia and seborrhea are among the most common skin disorders, with most patients exhibiting normal circulating androgen levels. The “cutaneous hyperandrogenism” is caused by in stiu overexpression of the androgenic enzymes and hyperresponsiveness of androgen receptors. Regulation of cutaneous steroidogenesis is analogous to that in gonads and adrenals. More work is needed to explain the regional difference within and between the androgn-mediated dermatoses. The pilosebaceous unit can act as an ideal model for studies in dermato-endocrinology.

 

[Galeaoman]

Try again. Some of us start balding as early as teens. There is age related hair loss that starts when the surrounds tissue can't support the follicle based on just integumentary cellular aging. We already know with age the skin gets much thinner thus less able to support follicles but in the case for male pattern baldness...neh keep thinking.

It does look like a complicated problem... The scalp also gets thin with age...

http://www.sciencedirect.com/science/article/pii/S0022202X15481540

The authors studied the thickness of the layers in both normal and bald scalps to determine the effect of aging on baldness. In non-bald subjects, 1) each scalp layer changes with aging; 2) the most noticeable changes are in the layers that contain hair; 3) the condition of the galea is influenced by aging. In bald subjects, 1) in early male pattern alopecia no changes occur in scalp thickness; 2) in advanced baldness, all skin layers except the galea exhibit definite thinning.

 

[H]

Now that I think about it the theory of too much fluid in the scalp seems reasonable. My grandpa has varicose veins as well as swelling in his legs (they are massive) he has had them drained but now wears compression socks to help. He has no hair on his legs whatsoever they are bare. When I asked him how long he said he can't remember but he remembers having hair on his legs as a young adult before his legs began swelling.

 

[Armando Jose]

Senescent balding and Androgenetic Alopecia are two totally different processes, but they are confused because senescent thinning can make Androgenetic Alopecia more pronounced. Also Androgenetic Alopecia progresses with age but is not itself a result of aging tissues.

+1

"End of aging = End of Balding" No. All cells in our organism are aging, then why hair loss in certains areas in common alopecia?

I remember Bryan Shelton, yes, He had much research knowledge with regards to male pattern baldness.

Pilosebaceous units are interesting...


https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835896/

Mr Zouboulis is a great scientist and bald. Sadly, my own ideas seem be not very important for him, only test if DHT exist in the pilosebaceous unit in scalp hair of boys/girls years before puberty (4 or 5 years old) could be very important to try solve which is the trigger of common alopecia. I have no lab to make this test.

 

[Galeaoman]

+1

"End of aging = End of Balding" No. All cells in our organism are aging, then why hair loss in certains areas in common alopecia?

With respect to the Hamilton study, I recall reading that 20 year old castrates injected with testosterone started going bald at the normal rate while 60 year old castrates injected with testosterone progressed to almost completely bald in a few months. Genetics could be strongly implicated in male pattern baldness.

Can long lost hair "regrow"? ...maybe in some rare cases...

https://www.hairlosstalk.com/interact/threads/question-for-bryan.29321/

http://www.hairlosscure2020.com/so-...s-of-the-scalp-can-regenerate-long-lost-hair/

https://www.ncbi.nlm.nih.gov/pubmed/1977262

Spironolactone is a diuretic and also regrows hair in some cases. Maybe in agreement with the Foote hypothesis of balding.

 

[Gone]

Genetics could be strongly implicated in male pattern baldness.

Yes

 

[Galeaoman]

Perhaps on a bald scalp the sweat glands become enlarged as the hair follicles become miniaturized. More research is required to investigate this idea. As mentioned in a previous post, humans are naked apes that have less body hair than the other mammals that are covered with fur. Early humans did a lot of persistence hunting, tracking, running, and walking, persistently chasing an animal until the animal suffered heat exhaustion and collapsed. Furry animals have much less sweating abilities than the relatively fur-less humans. One exception is the American hairless terrier that has sweat glands all over its body... No fur = more sweating for mammals...?

https://www.acs.org/content/acs/en/.../animal-survival-in-extreme-temperatures.html

Do animals sweat? Most don’t, but some do. Dogs sweat mainly between the pads on the bottom of their paws. One notable exception is the American hairless terrier, which has sweat glands all over its body, illustrating the fact that fur tends to inhibit sweating because if the sweat can’t evaporate it doesn’t help in the cooling process.

 

[Gone]

The type of sweat glands that connect to hair follicles are called apocrine, whereas the sweat glands that open in an exocrine manner to the skin's surface are described as "eccrine." There are also apoeccrine sweat glands which display traits of both types. Human hair follicles on the scalp do not possess apocrine sweat glands; sweat glands are not relevant to Androgenetic Alopecia in the way you're suggesting.

 

[Galeaoman]

The type of sweat glands that connect to hair follicles are called apocrine, whereas the sweat glands that open in an exocrine manner to the skin's surface are described as "eccrine." There are also apoeccrine sweat glands which display traits of both types. Human hair follicles on the scalp do not possess apocrine sweat glands; sweat glands are not relevant to Androgenetic Alopecia in the way you're suggesting.

I know my scalp sweats more than it did when it was covered with hair. There seems to be an inverse relation between sweating and hair growth. These are just my own personal observations regarding these complex topics of hair growth, hair loss, and how hair relates to other aspects of the skin... A sweaty scalp would also help to cool off a large brain.

Apocrine sweat glands are also in the scalp...

http://health.howstuffworks.com/wellness/men/sweating-odor/apocrine-sweat-glands.htm

That's because apocrine sweat glands are found in the places where we have the most hair follicles (the scalp, armpits and groin)

 

[coolio]

The sweat gland issue might be relevant to why we look like hairless apes instead of Gorillas. But male pattern baldness probably shows up as a genetic relic that helped our ancestors get enough sun exposure (vitamin D) in colder climates.

Bald humans are the ones who have heavy beards + ancestral climate was colder weather. Remove either of those variables and the baldness doesn't happen much at all. Women. Children. Warmer climates. Ethnic groups without heavy beards. Etc.

 

[H]

Bald humans are the ones who have heavy beards

With alot of exceptions, nope keep thinking. Unless everyone here has a lumberjack face fur going on and im the 1%? My cousin has had hair on his face and chest since he was 12 still has a full thick head of hair. While my facial hair is getting thicker its nothing to write home about and I hardly even grow hair under my armpits yet my scalp is becoming bare. Nips are a different thing altogether though i have no idea whats going on there....

 

[coolio]

With alot of exceptions, nope keep thinking. Unless everyone here has a lumberjack face fur going on and im the 1%? My cousin has had hair on his face and chest since he was 12 still has a full thick head of hair. While my facial hair is getting thicker its nothing to write home about and I hardly even grow hair under my armpits yet my scalp is becoming bare. Nips are a different thing altogether though i have no idea whats going on there....

It doesn't work like this at the individual level. It works at the genetic/race/age/demographic level.

It doesn't hit children - no facial hair.
It doesn't hit women - no facial hair.
It doesn't hit warm-weather races - no bundled-up clothing.
It doesn't hit Native American Eskimos - no facial hair.

It hits the living sh*t out of Caucasian adult men. Big facial hair is common in the race + mainly cold weather ancestry.

 

[S Foote.]

I know my scalp sweats more than it did when it was covered with hair. There seems to be an inverse relation between sweating and hair growth. These are just my own personal observations regarding these complex topics of hair growth, hair loss, and how hair relates to other aspects of the skin... A sweaty scalp would also help to cool off a large brain.

Apocrine sweat glands are also in the scalp...

http://health.howstuffworks.com/wellness/men/sweating-odor/apocrine-sweat-glands.htm



View attachment 46585

I refer to this relationship in this letter I have been sending to scientists in Human evolution research below. I suggest everyone should read the Cabanac sweating study I quote. This is one of the rare real world in-vivo Human study's, about androgen related hair loss/growth.

Modern Human Hairlessness

Stephen Foote.

This short paper is intended to elaborate upon the dermal interaction described in my article below, in terms of Human evolution. In particular the debate about modern Human hairlessness, and increased sweating capacity.

https://www.academia.edu/17570665/A...nt_Hair_Research_and_an_Overlooked_Connection.

The evidence outlined in my article indicates that the hair cycle and structure of the follicle, evolved to take advantage of pressure based spatial growth controls, recognised as controlling all normal tissue growth in-vivo.

http://phys.org/news/2014-04-room-tissue-growth-cell-response.html

The link this makes with sweating capacity described in my article, strongly supports the heat stress Hypothesis of Human hairlessness as described by Wheeler.

http://www.sciencedirect.com/science/article/pii/S0047248484800792

According to this dermal interaction the changes in dermal fluid levels and pressures linked to environmental temperature changes, also change hair growth and sweating capacity. In cold conditions hair growth is increased and sweating capacity reduced, and in hot conditions hair growth is reduced and sweating capacity is increased.

The important thing here in terms of Human evolution, is that the means to create modern Human hairlessness and increased sweating capacity already existed in hairy mammals and primates, and this is heat stress related. Over the long term these heat stress response characteristics would become selected for, and a permanent dermal condition in Humans. The evolution of the fat layer in Humans could also aid in making our hairlessness permanent.

I think it is logical that the dermal fat layer we have, evolved alongside our hairlessness and not before. There would be no stimulus for this while we still had fur. I agree with Wheeler that this fat layer acts as a core temperature stabilizer, that still allows efficient dermal heat shedding when necessary. This fat layer could also restrict dermal tissue fluid drainage into deeper tissues, so encouraging the permanently higher dermal fluid pressures that maintain our hairlessness and increased sweating capacity. I think the differences in eyebrow tissue could tell the story here, as i refer to in my article.

I also agree that scalp hair was important as Sun protection in early bipedalism, as Wheeler describes. But modern Human scalp hair can grow over two feet long. Having long hair hanging over your eyes and ears is a real problem in terms of survival, unless by the time our hair got to be this long, we had also developed the sense to tie it back or cut it? I think there is a logical connection here to increasing scalp hair length through this dermal interaction, and the changes necessary for the evolution of our brain.

I also think this recent in-vivo study is important. https://www.ncbi.nlm.nih.gov/pubmed/3203673

Whilst most including myself don’t agree with the authors conclusion about a cranial radiator, (most agree our hairless body is the radiator), the hard data here clearly confirms this dermal relationship in modern Humans. Significant changes in hair growth are linked to significant changes in sweating capacity. It is the modern Human link to androgen action in this study, that results in the testable link to gender related diseases I describe in my article.

Stephen Foote

 

[Gone]

I know my scalp sweats more than it did when it was covered with hair. There seems to be an inverse relation between sweating and hair growth. These are just my own personal observations regarding these complex topics of hair growth, hair loss, and how hair relates to other aspects of the skin... A sweaty scalp would also help to cool off a large brain.

Apocrine sweat glands are also in the scalp...

http://health.howstuffworks.com/wellness/men/sweating-odor/apocrine-sweat-glands.htm



View attachment 46585

Every other source besides the one you linked contradicts this. Yes the scalp contains sweat glands, but they're not connected to the hair follicle. Apocrine sweat glands are the kind that result in body odor and are activated by puberty/hormones. Pubic hair is an example of a hair type that has apocrine sweat glands in its follicular unit. Scalp hair follicles don't act in the same way. The scalp sweats but not through the follicle.

 

[Galeaoman]

Every other source besides the one you linked contradicts this. Yes the scalp contains sweat glands, but they're not connected to the hair follicle. Apocrine sweat glands are the kind that result in body odor and are activated by puberty/hormones. Pubic hair is an example of a hair type that has apocrine sweat glands in its follicular unit. Scalp hair follicles don't act in the same way. The scalp sweats but not through the follicle.

Maybe you can give some links to your authoritative sources that say there are no apocrine sweat glands in the scalp? I think both types of sweat glands are in the scalp...

This is not a actually debate about whether apocrine sweat glands are in the scalp but it is a question about does the scalp sweat? Yes, the scalp sweats, especially the hairless scalp. Sweat is used in the function of thermoregulation.

https://www.ncbi.nlm.nih.gov/pubmed/1778649

The full text pdf can be downloaded free at this link

https://www.researchgate.net/publication/21376442_The_evolution_of_sweat_glands

Mammals have two kinds of sweat glands, apocrine and eccrine, which provide for thermal cooling. In this paper we describe the distribution and characteristics of these glands in selected mammals, especially primates, and reject the suggested development of the eccrine gland from the apocrine gland during the Tertiary geological period. The evidence strongly suggests that the two glands, depending on the presence or absence of fur, have equal and similar functions among mammals; apocrine glands are not primitive. However, there is a unique and remarkable thermal eccrine system in humans; we suggest that this system evolved in concert with bipedalism and a smooth hairless skin.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1281456/

The only two mammals capable of sustained running are horses and human beings. Copious sweat is produced in horses by apocrine glands and in humans by eccrine glands. The role of the eccrine sweat glands in human thermoregulation is evident, but what functions do apocrine and sebaceous glands fulfil? There has been surprisingly little hypothesizing about this. It is not even certain that the original simple division of human sweat glands into apocrine and eccrine is realistic. It will be assumed here that the apocrine glands are a reality—that their dismissal in the past as no more than ‘atavistic scent glands’ was erroneous.

The role of sebaceous glands in humans has been regarded as uncertain, but the fact that they are under complex hormonal control argues against their being vestigial. In humans sebaceous glands occur over much of the body. They are usually associated with hair follicles and are particularly well developed in certain areas such as the scalp, face, upper back and chest. It is noteworthy that, in a naked bipedal hominine, these are the areas most exposed to weather and rain.

Why does my scalp smell?

http://www.healthcare-online.org/Why-Does-My-Scalp-Smell.html

The Function of Sweat Gland

The apocrine sweat glands on your head can produce a certain kind of fatty sweat. This kind of sweat will attack and break down any bacteria it comes into contact with, resulting in a bad odor. Since oil can prompt more bacteria growth, you might wind up with a terrible odor on your hair. Keep in mind that these apocrine sweat glands appear wherever there is hair on your body, so you might have the same problem with other areas, too.

 

[Galeaoman]

I also think this recent in-vivo study is important. https://www.ncbi.nlm.nih.gov/pubmed/3203673

Whilst most including myself don’t agree with the authors conclusion about a cranial radiator, (most agree our hairless body is the radiator), the hard data here clearly confirms this dermal relationship in modern Humans. Significant changes in hair growth are linked to significant changes in sweating capacity. It is the modern Human link to androgen action in this study, that results in the testable link to gender related diseases I describe in my article.

Stephen Foote

Maybe that is true. The whole surface area of the skin can be used for cooling. Humans can run better in the heat than other hairy mammals even though they are slow runners, they can run prey animals to exhaustion...

http://www.nytimes.com/2009/10/27/health/27well.html

Most mammals can sprint faster than humans — having four legs gives them the advantage. But when it comes to long distances, humans can outrun almost any animal. Because we cool by sweating rather than panting, we can stay cool at speeds and distances that would overheat other animals. On a hot day, the two scientists wrote, a human could even outrun a horse in a 26.2-mile marathon.

Is the eccrine gland an integral, functionally important component of the human scalp pilosebaceous unit?

https://www.ncbi.nlm.nih.gov/pubmed/26513332

https://www.researchgate.net/public...mponent_of_the_human_scalp_pilosebaceous_unit

The pilosebaceous unit (PSU) and the eccrine sweat gland (ESG) are classically described as completely independent skin appendages. However, careful inspection of scalp follicular units reveals that the secretory segment of the ESG spatially approximates the hair follicle in a position below the sebaceous gland and the insertion of the arrector pili muscle. Therefore, we propose here that, contrary to conventional wisdom, the PSU and the ESG should not be viewed in isolation, and may form instead, along with the arrector pili muscle and the apocrine gland (where present),one functional unit. For this, we suggest the more inclusive term of 'Hair Cluster' (HC). If confirmed, e.g. by 3D imaging techniques, the novel concept of a functional HC, whose individual components may communicate via secreted molecules and may share selected progenitor cell populations for HC repair/regeneration, has major physiological and pathological implications, which are briefly discussed.

 

[Gone]

Even if the eccrine sweat gland "spatially approximates" the hair follicle, or shares its cell population, or is considered part of a follicular cluster, the eccrine sweat glands of the scalp are still eccrine sweat glands, and by definition don't empty into the hair canal.

"Is the eccrine gland an integral, functionally important component of the human scalp pilosebaceous unit?"

Well, no, because by definition the pilosebacious unit involved the hair follicle, arrector pili muscle and sebacious gland. If they want to call it a follicular cluster which includes the eccrine sweat gland like they suggested, they can do so. But the sweat itself never makes contact with the hair follicle, it's excreted to the skin's surface.

 

[Galeaoman]

Even if the eccrine sweat gland "spatially approximates" the hair follicle, or shares its cell population, or is considered part of a follicular cluster, the eccrine sweat glands of the scalp are still eccrine sweat glands, and by definition don't empty into the hair canal.

"Is the eccrine gland an integral, functionally important component of the human scalp pilosebaceous unit?"

Well, no, because by definition the pilosebacious unit involved the hair follicle, arrector pili muscle and sebacious gland. If they want to call it a follicular cluster which includes the eccrine sweat gland like they suggested, they can do so. But the sweat itself never makes contact with the hair follicle, it's excreted to the skin's surface.

Hair impedes the abilty of sweat to cool the skin. It makes sense that there is some kind of inverse relation between scalp "eccrine" sweat glands and hair follicles.

 

[Gone]

Hair impedes the abilty of sweat to cool the skin.

What?

It makes sense that there is some kind of inverse relation between scalp "eccrine" sweat glands and hair follicles.

What is this inverse relationship?