Sebaceous gland is not a phylogenetic relict

[Armando Jose]

A new point of view regarding sebaceous gland,
Sorry Bryan, Mr. Kligman was wrong.

Have a nice day

Armando

Exp Dermatol. 2008 Jun;17(6):542-51.

Frontiers in sebaceous gland biology and pathology.
Zouboulis CC, Baron JM, Böhm M, Kippenberger S, Kurzen H, Reichrath J, Thielitz A.
Department of Dermatology, Dessau Medical Center, Dessau, Germany. christos.zouboulis@klinikum-dessau.de
The development of experimental models for the in vitro study of human sebaceous gland turned down the theory of a phylogenetic relict and led to the identification of several, unknown or disregarded functions of this organ. Such functions are the production of foetal vernix caseosa, the influence of three-dimensional organization of the skin surface lipids and the integrity of skin barrier and the influence on follicular differentiation. In addition, the sebaceous gland contributes to the transport of fat-soluble antioxidants from and to the skin surface, the natural photoprotection, the pro- and antiinflammatory skin properties and to the innate antimicrobial activity of the skin. It is mainly responsible for skin's independent endocrine function, the hormonally induced skin ageing process, the steroidogenic function of the skin as well as its thermoregulatory and repelling properties and for selective control of the hormonal and xenobiotical actions of the skin. Interestingly, sebocytes, at least in vitro, preserve characteristics of stem-like cells despite their programming for terminal differentiation. This review reports on various sebaceous gland functions, which are currently under investigation, including its role on the hypothalamus-pituitary-adrenal-like axis of the skin, the impact of acetylcholine on sebocyte biology, the activity of ectopeptidases as new targets to regulate sebocyte function, the effects of vitamin D on human sebocytes, the expression of retinoid metabolizing cytochrome P450 enzymes and the possible role of sebum as vehicle of fragrances. These multiple homeostatic functions award the sebaceous gland the role 'brain of the skin' and the most important cutaneous endocrine gland.
PMID: 18474083 [PubMed - in process]

 

[ghg]

Just remember that you can prevent baldness by letting your hair grow. Right, Armando? It really is all you have to do! It's amazing.

 

[IBM]

What Armando Jose had in mind to create the long hair anti baldness theory?

 

[ghg]

What Armando Jose had in mind to create the long hair anti baldness theory?

Probably not much at all... it's bs. My bro has never had his hair cut short yet he's balding just like me. And what about bald hippies? And what about ppl who lived before the shaving/buzzing became fashionable not so long ago? Why did they go bald? Oh I think I know! They didn't use jojoba oil.

 

[Armando Jose]

Hi guys;

Thank you for your sarcasm, but the link between halr lenght and alopecia is only a corollary of my theory. Please look in the right direction where problems in sebum flow are important in common hair loss.

BTW the post is about if sebaceous gland is a philogenetic relict ot not?

Any input?

Armando

 

[Armando Jose]

More interesting and new inputs
http://www.nature.com/jid/journal/v128/ ... 1200a.html



Sebogenic hypothesis of hair follicle phylogeny
Kurt S, Stenn
Aderans Reseach Institute, Philadelphia, PA, USA
Recognizing that virtually all hair follicles are associated with a sebaceous gland it is relevant when considering the evolutionary origin of the hair follicle to ask which came first: the hair follicle, or its sebaceous gland. The cutaneous challenge for organisms adapting to land from a water environment was/is the development of a water-impermeable cover. Plant and animal forms have successfully executed this adaptation by means of an integument rich in surface waxes and lipids. We present here associated evidence supporting the sebaceous gland first hypothesis where the hair shaft precursor is viewed to have derived from a sebaceous gland lobe as a wick to efficiently draw the secretions of the deep-lying, lipid secretions to the surface. While the paleontological record is scant to silent, some support for this hypothesis is found in extant Mammalia. Moreover, cell and molecular mechanistic studies show that hair follicle inductive signals, when weak, result in a sebaceous gland, suggesting that
the first, primitive, signal is for lipid gland formation. Needed studies to test, and implications of, the hypothesis will be reviewed.


http://iid2008.org/meetings/sshr-abs.pdf


Best regards

Armando