brushing for receding hairline?

[Bryan]

Its good ask for studies (*)...

I don't think that information about a specific "sebaceous gland defect" in mice has anything to do with what I was talking about. I think it demonstrates a problem in mice with the way that cells in the area of the pilosebaceous unit differentiate into either sebaceous glands or hair follicles. I think that's light-years away from what I was talking about.

but I know that you are a formed person that like read the current investigations . There is a lot of them regarding the term “pilosebaceous unitâ€￾ better than hair follicle in the investigation of hair biology. Do you know a single study or observation where exist hair follicle without sebaceous gland? Surely don’t.

No I don't, but all that proves is that in humans, sebaceous glands are normally associated with the hair follicle. That certainly doesn't prove that sebaceous glands are ESSENTIAL for the growth of hair. Armando, I want you to admit that you don't have any scientific evidence to support what you've been saying.

 

[armandein]

Dear Bryan;

The scientific evidence is that hair always have been associated to a sebaceous gland, are you agree?
Kurt Steen, M.D, write:
All hair follicles form and function in association with a sebaceous gland (Sokolov, 1982; Bell, 1986; Wheatley, 1986). Although sebaceous glands may form and function in the absence of a hair follicle (for example, in the eyelid, the vermilion surface of the lips, the nipples and areolae, prepuce, labia minora; Montagna and Parakkal, 1974), hair follicles are not formed, nor do they function, normally in the absence of a sebaceous gland (Williams and Stenn, 1994; Philpott et al., 1996; Sundberg et al., 2000; Porter et al., 2002; Allen et al., 2003; Vidal et al., 2005).

Any proof against this fact?

Have a nice day
Armando

P.D. My sincere condolences
http://www.cnn.com/2009/US/11/05/texas. ... index.html

 

[Bryan]

The scientific evidence is that hair always have been associated to a sebaceous gland, are you agree?

Yes, I agree. But that doesn't prove that hairs can't grow without sebum.

Kurt Steen, M.D, write:
All hair follicles form and function in association with a sebaceous gland (Sokolov, 1982; Bell, 1986; Wheatley, 1986). Although sebaceous glands may form and function in the absence of a hair follicle (for example, in the eyelid, the vermilion surface of the lips, the nipples and areolae, prepuce, labia minora; Montagna and Parakkal, 1974), hair follicles are not formed, nor do they function, normally in the absence of a sebaceous gland (Williams and Stenn, 1994; Philpott et al., 1996; Sundberg et al., 2000; Porter et al., 2002; Allen et al., 2003; Vidal et al., 2005).

Any proof against this fact?

Have you actually READ any of those cited studies? Instead of just citing them for me one after another, please tell me what those studies SAY, and how they supposedly support your claim that hairs can't grow without sebum.

 

[Andrea]

Sorry for my terrible English but I'll try to explain my opinion:
I have an Italian study done by respectables Doctors (S.Passi A. D'Ippolito) but I'm not able to translate it.
So, this work shows that in patients HIV positive with eczema and in patients HIV negative with seborroic or atopic dematitis there is a LACK of sebum in the interested zone...Then, the authors have analyzed the composition of sebum with modernal instruments. It seems that the human's sebum is unique in the animal and vegetal world. Sebum have protective effects against UVB, antioxidant properties, but NOT antufungal properties as someone says.
Then, the Doctors analyzed the blood and ALL patients with eczema, atopic dermatitis, seborroic dermatitis (HIV positive and negative) shows a severe deicit of fatty acids W6 W3 and antioxidants (vit.E and ubichinon).
After nearly 1 months of a specific diet with EPA, DHA, animal liver, animal heart, vit.E and ubichinon (supplements) the dermatits completely cleared up (82%) or improoved. The SEBUM returned to a normal level.
The Docotrs also noticed a severe deficit in DESATURASE enzyme that is able to form polynsatured (W3 W6) fatty acids from linoleic acid (olive oil) ad linolenic acid. The only way to form polynsatured fatty acid W3 W6 in a person with desaturase deficit is an external introduction with diet (fish, hearth and animal liver). The deficit of desaturase is common in most type of skin's desease.
So, the sebum shows protective and anti inflammatory effects.
But, when there is an insufficient sebum production, the scalp (or skin in general) is more prone to external injury but too much sebum increase the possible of infections and bacterial proliferation.
So, in my opinion, a RIGHT DOSE of sebum "add something" to the hair in term of protection and antioxidants effects. The fatty acid also have an inibitory effects against 5 Alpha Reductase...
Don't forget that in an ADULT the sebum production is infkuenced by hormone balance, stress and diet that also could change the COMPOSITiON of sebum.
The children have soft hair and perfect skin because have efficient Desaturase enzyme and a right dose of polynsatured fatty acid and antioxidants. The absence of a potent adrongen stimuli also avoid an overexpression of sebum production.
I'm sorry, I'll try to transalate this study.
Bye
Andrea

 

[Bryan]

But, when there is an insufficient sebum production, the scalp (or skin in general) is more prone to external injury...

What kind of "external injury" are you talking about?

Something I've already discussed with Armando is the example of people with CAIS (Complete Androgen Insensitivity Syndrome). Despite the fact that they produce virtually no sebum, they have flourishing scalp hair. That would appear to contradict his theory that sebum is essential for the growth of hair.

 

[Andrea]

I mean UVB, climatic conditions, oxidative stress...
Why, Bryan, do you use the word "VIRTUALLY no sebum" about CAIS?
My suspect is that the EXTERNAL level of sebum is NOT an attendible test to check the real activity of sebaceous glands.
In other words the lack or reduced level of sebum on the skin don't mean that the sebaceous glandsare inactive but, MAYBE, that there is a RIGHT production of sebum that goes into follicle and create a healthy hair and soft skin.
When we touch the "stratus" of sebum there is already an overproduction...
Surely I don't think that sebum is the only factor to have healthy hair but plays a role...
Bye
Andrea

Obviously I'm interested to read studies that goes in a different way...

 

[armandein]

But, when there is an insufficient sebum production, the scalp (or skin in general) is more prone to external injury...

What kind of "external injury" are you talking about?

Something I've already discussed with Armando is the example of people with CAIS (Complete Androgen Insensitivity Syndrome). Despite the fact that they produce virtually no sebum, they have flourishing scalp hair. That would appear to contradict his theory that sebum is essential for the growth of hair.

Mr Bryan want to be anchor in the past when it is thought that persons exist persons with COMPLETE androgen insensitivity syndrome, I don't think so, complete non androgens people are not compatible with life in my opinion.
are you aware with the lattest investigation regarding not only 1 or 2 isoenzymes with 5 alfareductase?, now there is a 3 type. I recommend this recent study:
Biosynthesis of Dihydrotestosterone by a Pathway that Does Not Require Testosterone as an Intermediate in the SZ95 Sebaceous Gland Cell Line

Journal of Investigative Dermatology advance online publication, 8 October 2009; doi:10.1038/jid.2009.225


To further characterize 5a-Red activity,
we added 1 mM finasteride, a well
known 5a-Red inhibitor, to the incubation
medium (Figure 1c). Although
finasteride is eightfold less efficient in
the inhibition of type 1 compared with
type 2 5a-Red and is identified in the
literature as a specific inhibitor of type
2 5a-Red (Andersson et al., 1991), we
found, using human embryonic kidney
(HEK)-293 cells stably expressing types
1, 2, and 3 5a-Reds, that this compound
inhibits these enzymes with IC50
(half maximal inhibitory concentration)
values of 107, 14, and 17 nM, respectively,
thus indicating that finasteride is
still a relatively potent inhibitor of type 1
5a-Red.

Armando

 

[armandein]

Sorry for my terrible English but I'll try to explain my opinion:
I have an Italian study done by respectables Doctors (S.Passi A. D'Ippolito) but I'm not able to translate it.
So, this work shows that in patients HIV positive with eczema and in patients HIV negative with seborroic or atopic dematitis there is a LACK of sebum in the interested zone...Then, the authors have analyzed the composition of sebum with modernal instruments. It seems that the human's sebum is unique in the animal and vegetal world. Sebum have protective effects against UVB, antioxidant properties, but NOT antufungal properties as someone says.
Then, the Doctors analyzed the blood and ALL patients with eczema, atopic dermatitis, seborroic dermatitis (HIV positive and negative) shows a severe deicit of fatty acids W6 W3 and antioxidants (vit.E and ubichinon).
After nearly 1 months of a specific diet with EPA, DHA, animal liver, animal heart, vit.E and ubichinon (supplements) the dermatits completely cleared up (82%) or improoved. The SEBUM returned to a normal level.
The Docotrs also noticed a severe deficit in DESATURASE enzyme that is able to form polynsatured (W3 W6) fatty acids from linoleic acid (olive oil) ad linolenic acid. The only way to form polynsatured fatty acid W3 W6 in a person with desaturase deficit is an external introduction with diet (fish, hearth and animal liver). The deficit of desaturase is common in most type of skin's desease.
So, the sebum shows protective and anti inflammatory effects.
But, when there is an insufficient sebum production, the scalp (or skin in general) is more prone to external injury but too much sebum increase the possible of infections and bacterial proliferation.
So, in my opinion, a RIGHT DOSE of sebum "add something" to the hair in term of protection and antioxidants effects. The fatty acid also have an inibitory effects against 5 Alpha Reductase...
Don't forget that in an ADULT the sebum production is infkuenced by hormone balance, stress and diet that also could change the COMPOSITiON of sebum.
The children have soft hair and perfect skin because have efficient Desaturase enzyme and a right dose of polynsatured fatty acid and antioxidants. The absence of a potent adrongen stimuli also avoid an overexpression of sebum production.
I'm sorry, I'll try to transalate this study.
Bye
Andrea

Hi Andrea;

could you send me the study in italian?
I am very interested in it.

TIA
Armando

 

[S Foote.]

Armando.

If i understand you properly, you claim that the androgen effect in male pattern baldness is caused by an effect of androgens on sebaceous glands, that then causes sebum to reduce hair production?

So could you explain the role of this mechanism in androgen increased hair growth, beard, bodyhair?

Or do you claim some other mechanism for the androgen effect on body hair?

S Foote.

 

[armandein]

Armando.

If i understand you properly, you claim that the androgen effect in male pattern baldness is caused by an effect of androgens on sebaceous glands, that then causes sebum to reduce hair production?

So could you explain the role of this mechanism in androgen increased hair growth, beard, bodyhair?

Or do you claim some other mechanism for the androgen effect on body hair?

S Foote.

Thank you for your interest in my ideas, honestly, it is possible that I don't expresse well,. I think that a healthy hair needs an operative sebaceous gland (SG), it's clear that SG need androgens to be functional. Body hair don't appear in the adolescence, from birth they exist miniarurided, but don't have SG and sebum in order to be terminals. It is in the moment when our body make testosterone when hairs become larger.
The problem is not directly related to sebum formation but with the elimination of it because it is very inestable, and possibly interfere with steem cells, among other things.
The key is that years before puberty exist androgens in the vicciniy of terminals hairs, in this case scalp hairs.

Armando

 

[S Foote.]

Armando.

If i understand you properly, you claim that the androgen effect in male pattern baldness is caused by an effect of androgens on sebaceous glands, that then causes sebum to reduce hair production?

So could you explain the role of this mechanism in androgen increased hair growth, beard, bodyhair?

Or do you claim some other mechanism for the androgen effect on body hair?

S Foote.

Thank you for your interest in my ideas, honestly, it is possible that I don't expresse well,. I think that a healthy hair needs an operative sebaceous gland (SG), it's clear that SG need androgens to be functional. Body hair don't appear in the adolescence, from birth they exist miniarurided, but don't have SG and sebum in order to be terminals. It is in the moment when our body make testosterone when hairs become larger.
The problem is not directly related to sebum formation but with the elimination of it because it is very inestable, and possibly interfere with steem cells, among other things.
The key is that years before puberty exist androgens in the vicciniy of terminals hairs, in this case scalp hairs.

Armando

Amando, with respect you are not explaining your ideas in terms of a proper scientific theory.

If you have an idea about how androgens effect hair growth, you have to explain the mechanisms involved, and why there is an opposite effect of androgens in different areas.

So could you elaborate on your theory step by step?

S Foote.

 

[Bryan]

I mean UVB, climatic conditions, oxidative stress...

In his article "The Uses of Sebum" (British Journal of Dermatology, Vol. 75, 1963), Kligman estimates that the thickness of sebum on the forehead of a very oily subject is only around 0.45 ? (micrometer) thick. The average thickness for other areas of the body with a lower density of sebaceous glands (such as the abdomen) is only around 0.05 ? (5/100 of 1 micrometer). Do you really think such a tiny submicroscopic ultrafilm of sebum is going to play much of a role against UVB, climatic conditions, and oxidative stress?

Why, Bryan, do you use the word "VIRTUALLY no sebum" about CAIS?

I'm always going to be very cautious when I speak about the levels of sebum produced by various population groups, and acknowledge that there may be _some_ tiny levels of sebum they produce, no matter how insignificant they may be.

My suspect is that the EXTERNAL level of sebum is NOT an attendible test to check the real activity of sebaceous glands.
In other words the lack or reduced level of sebum on the skin don't mean that the sebaceous glandsare inactive but, MAYBE, that there is a RIGHT production of sebum that goes into follicle and create a healthy hair and soft skin.

Well, we can get pretty silly and theorize/hypothesize all sorts of crazy ideas about how sebum is necessary for hair growth, can't we? But the real trick is finding scientific information which SUPPORTS those theories. I don't know of any, and I bet you don't, either. For example, people with CAIS (Complete Androgen Insensitivity Syndrome) produce no detectable levels of sebum (although they may produce a few molecules of it which aren't detectable), yet have luxuriant, flourishing scalp hair growth. Check the following study: "The Androgen Control of Sebum Production. Studies of Subjects with Dihydrotestosterone Deficiency and Complete Androgen Insensitivity", Julianne Imperato-McGinley, Teofilo Gautier, Li-Qun Cai, Benetta Yee, Jane Epstein, Peter Pochi. J Clin Endocrinol Metab 76: 524-528, 1993. Following the chart below is some of the text from the study, describing the experimental setup, subjects, and the results.

Subjects and Methods

Subjects

"Sebum production was evaluated in 12 subjects with inerited male pseudohermaphroditism due to 5a-reductase deficiency (MPH); 9 subjects were part of a large Dominican kindred, and 3 were from New Guinea. The mean age was 27 yr (age range, 19-40). Eight androgen insensitve (AI) subjects were evaluated with a mean age of 45 (age range, 15-78). Six AI subjects had their gonads intact when studied, and 2 subjects were on cyclic estrogen and progesterone replacement therapy after gonadectomy at the time of evaluation. Twenty-two normal adult Dominican males with a mean age of 28 yr (age range, 17-39), and 21 normal adult Dominican females with a mean age of 29.0 yr (age range, 18-37), normal menses, and no history of hirsutism or acne, were evaluated. Preadrenarchal boys and girls were also evaluated. This study group was comprised of 10 normal healthy Dominican boys ranging in age from 2-5 yr (average age was 3.7 yr), and 12 healthy Dominican girls ranging in age from 2-6 yr (average age was 4.3 yr). None of the children had clinical signs of secondary sexual development.

Procedures

"Measurement of sebum production was performed with Sebutape (Hermal Pharmaceutical Laboratories, Oak Hills, NY), a hydrophobic, polymeric film that measures sebum activity through the use of air-filled micropores. When sebum from the skin surface comes in contact with the tape, numerous tiny air cavities previously filled with air become filled with sebum. Consequently, sebum-filled pockets become transparent cavities forming a pattern of sebum droplet deposition.

"The test was performed in the following manner. The forehead of each subject was thoroughly cleaned with alcohol swabs. A Sebutape patch was placed on the forehead for 1 hr. The patch was removed and the amount of sebum measured on a scale of 0-5 using reference patterns provided in the kit. A zero (0) pattern was equol to no sebum production, whereas a five (5) pattern signified highest sebum output. The patches were read by the investigator (LC) who was blinded to the identity of the subjects.

Results

Sebum studies

"Ten normal boys and 12 normal girls between the ages of 2-6 years had no detectable sebum production by this methodology (Fig. 1), and had a sebum score of 0. Similarly, the sebum score of all adult subjects (with or without intact gonads) with complete androgen insensitivity was zero (Table 1) (Fig. 1)...

"The mean score for 21 control adult males was 4.4 +/- 0.6 which was significantly higher than the mean sebum score of 3.3 +/- 1.2, for 21 control adult females (P < 0.05) (Fig. 1).

"The mean sebum score of adult pseudohermaphrodites with 5a-reductase deficiency (4.5 +/- 0.6) was not significantly different from the mean score of normal adult males (4.35 +/- 0.6) (P < 0.05) (Fig. 1)."

When we touch the "stratus" of sebum there is already an overproduction...
Surely I don't think that sebum is the only factor to have healthy hair but plays a role...

Nah, I don't know of any scientific evidence at all that sebum plays any role in the growth of hair. And the evidence above of people with CAIS with luxuriant hair growth and no sebum production completely contradicts that notion.

 

[Bryan]

Mr Bryan want to be anchor in the past when it is thought that persons exist persons with COMPLETE androgen insensitivity syndrome, I don't think so, complete non androgens people are not compatible with life in my opinion.

See the study I posted just above. The individuals in that study did in fact have COMPLETE androgen insensitivity, and they were very much alive! Not only that, but they also have remarkable scalp hair growth!

 

[armandein]

Mr Bryan want to be anchor in the past when it is thought that persons exist persons with COMPLETE androgen insensitivity syndrome, I don't think so, complete non androgens people are not compatible with life in my opinion.

See the study I posted just above. The individuals in that study did in fact have COMPLETE androgen insensitivity, and they were very much alive! Not only that, but they also have remarkable scalp hair growth!

It's a pity when they onkly test forehead , "A Sebutape patch was placed on the forehead for 1 hr"
Other different thing is scalp.
COMPLETE include brain?
Androgen metabolism is vital to life, in my oppinion. Do you want to say that "CAIS" survive without neurosteroids?

Eur J Endocrinol. 2001 Dec;145(6):669-79.
Neurosteroid metabolism in the human brain.

Armando

 

[Bryan]

It's a pity when they onkly test forehead , "A Sebutape patch was placed on the forehead for 1 hr"

I wouldn't expect the results to be any different, if they had tested their scalps. Their androgen receptors are the same (non-functional) all over their body.

Other different thing is scalp.
COMPLETE include brain?

Yes.

Androgen metabolism is vital to life, in my oppinion.

Your opinion must be wrong, since they had eight of those individuals, ranging in age from 15 to 78!

Do you want to say that "CAIS" survive without neurosteroids?

I'm not sure about their levels of neurosteroids. All I know is that they have no androgenic stimulation, due to mutated (non-functional) androgen receptors.

 

[armandein]

Dear Bryan;

Can you say if CAIS persons have sebum in scalp hairs?
If yes, what is the mechanism as they have not androgen receptors suitable?

TIA

Armando

 

[Bryan]

Can you say if CAIS persons have sebum in scalp hairs? If yes, what is the mechanism as they have not androgen receptors suitable?

I'm not completely sure what you mean by "sebum in scalp hairs". Are you asking if the sebaceous glands in their scalps produce any sebum at all? I don't know if that's ever been tested, so I can't really say for sure; but as I said in my previous post, I would expect the sebaceous glands in their scalps to produce the same virtually undetectable levels of sebum that the ones in their foreheads produce.

 

[armandein]

Dear Bryan,

You are an early rise.

Despite if there is a study or there is not a study, sebum or greasy or how you want to say it, ....., It is neccesary that these people have sebum on the hair. His hair are in good condition.

OTOH You know very well that it is not the same forehead (or body) than scalp, over all in prepubertals.

Armando

 

[Bryan]

Despite if there is a study or there is not a study, sebum or greasy or how you want to say it, ....., It is neccesary that these people have sebum on the hair.

You keep saying that, but you don't have any scientific evidence to support that claim.

 

[Andrea]

Armando I'll send you a private message...

Bryan, thank you for the studies, I have some questions to you:

- Do you think that the sebum is completely useless for human's skin? Or just play a very limited role? In this case what is this "role"?

- Why people on ADT (Androgen Deprivation Theraphy) or Transgender frequently does experience a VERY DRY SKIN and VERY DRY HAIR if sebum didn't any sort of benefic effects? The same thing happened with Accutane that shrinks the sebaceous glands (istologically documented)...


Bye
Andrea