Docj077;
It is interesting the study of Valerie Horsley about the Blimp1 gene and its implication in the creation of sebaceous gland and hair. I didn’t know till now but he is one of the aprox. 50 genes implicated. Blimp1, mediating c-my expression, regulates the number of sebocytes and its division rate. Other two growth factors are Bmp6 and FGF18, which are expressed specifically in the bulge area. By the way, this is a very good team and his leader Elaine Fuchs a very brave, cute and interesting person. (
http://jcs.biologists.org/cgi/content/full/117/21/4877)
Respect at the progenitory cells of sebaceous gland, Fuchs writes in journal Cell
http://www.rockefeller.edu/pubinfo/news ... 1504_a.php
about the multipotent power of these stem cells and watched them travel either down to the bulb of the hair follicle to form new hair, or up to the surface to create new skin epidermis and sebaceous gland. “The grafted cells, all derived from the, made new hair, skin and sebaceous glands, which excrete oil to lubricate the hair.â€
Then it is possible conclude that sebaceous gland are originated from the same stem cells that dermal papillae cells but, independently, I only want to emphasize the intrinsic relation of hair and sebaceous gland.
The possible sebaceous infiltration into the dermis, the plugging and a massive immune response it is possible but is easier that this same process happen more near from hair follicle.
You say that follicle develops first and the signals the sebaceous unit to develop. I don’t know really what happen but in a work with a good model of human hair, in pig, the author indicate that sebaceous gland is operative in stage 8b, and later in stage 9a the spherical papilla is surrounded by the hair bulb. (Development of hair coat and skin glands in fetal integument, J Anat 144:201-220, 1986)
You point out that sebaceous unit-follicle communication is required for proper formation of the pilosebaceous unit, however once the unit is formed sebum is not required for growth. Have you any reference? I have one study where a correlation between penetration properties, hair growth activity and sebum secretion was found, so they could confirm the hypothesis open and closed follicles as well inactive and active hair follicles. (Follicular penetration and targeting, J Invest Dermatol Proc. 10:301-303, 2005.
As for the genetics, the main issue. You talked very well about a genetic difference between non-balding and balding hair follicle but I didn’t ask it. I asked about the difference between HEALTHY scalp hairs, hairs from the top and around head. My idea is there is not differences between all scalp hairs, no differences between sexes, including prepubertals. I don’t know any study at this respect. So difficult is it, especially when most of investigators point out at this supposed genetic difference between scalp hairs?
To Michael:
According to my theory any strategy to avoid problems with sebum flow (creation&elimination) would be positive to prevent common hair loss, and combing hair backward is one of them, due the increase with physical contact among hairs. I posted a photo with a woman with frontal hair receding due a short fringe combed forward.
Have sebaceous gland operative in hairs from eyelashes, eyebrows, toe or fingers?
Please read in
http://en.wikipedia.org/wiki/Demodex_mite
Demodex folliculorum and Demodex brevis are the only Demodex mites that have been found on humans. D folliculorum is found in hair follicles while D brevis lives in sebaceous glands connected to hair follicles. Both species are primarily found in face, near the nose, the eyelash and eyebrowns, but also occur elsewhere on the body.
On the other hand insulin-resistance is only a theory and don’t explain the higher number of affected persons nowadays.
Respect at fluridil there is a commentary:
Dr. Sowak who did this " study " is a leading official at Interpharma which produces the stuff. Nearly everyone at Biophysica is connected to Interpharma.Nobody in the scientific world took this "study " serious.....
After disappointing sales and the refusal of French authorities to approve it they simply start a new try
Also I don’t see a lot of people using this med. Fluridil is a receptor blocker and would be a good alternative to finasteride. OTOH fluridil have a role in sebaceous gland and disminih the production of sebum. Maybe the supossed good results are connected to sebum regulation?
Another good commentary:
Fluridil started off with alot of promise, but has lost credibility over the years.
They lack any independant studies and the only available studies done were performed by the manufacture of the product themselves. It has been available for a few years now so you would think that someone would take interest in the stuff.
We must also understand that since the product cannot come in touch with water, it makes it a difficult topical to add for those of us who use other treatments such as minoxidil.
On top of this, the product is very high in Isopropyl alcohol which can irritate the scalp and dry out the hair.
Please understand that I am not against Fluridil; I would love it if the stuff worked. However, after being available for as long as it has with no independant studies supporting it, as well as the tepid feedback from this and other sites, makes me a little skeptical about the product.
You know this study, don’t you?, have you any commentary?
Effect of 5alpha-Dihydrotestosterone and Testosterone on Apoptosis in Human Dermal Papilla Cells.Winiarska A, Mandt N, Kamp H, Hossini A, Seltmann H, Zouboulis CC, Blume-Peytavi U.
Department of Dermatology and Allergy, Charite-Universitatsmedizin Berlin, Berlin, Germany.
Pathogenetic mechanisms in androgenetic alopecia are not yet fully understood; however, it is commonly accepted that androgens like testosterone (T) and 5alpha-dihydrotestosterone (5alpha-DHT) inhibit hair follicle activity with early induction of the catagen. Thus, we investigated the influence of T and 5alpha-DHT on proliferation, cell death and bcl-2/bax expression in cultured dermal papilla cells (DPC) from nonbalding scalp regions of healthy volunteers. T and 5alpha-DHT induced apoptosis in DPC in a dose-dependent and time-related manner; in addition a necrotic effect due to T at 10(-5)M was found. Interestingly, bcl-2 protein expression was decreased in T- and 5alpha-DHT-treated cells, leading to an increase in the bax/bcl-2 ratio. In addition, T and 5alpha-DHT induced proteolytic cleavage of caspase 8 and inhibited proliferation of DPC at 10(-5)M. High concentrations of T and 5alpha-DHT were needed to induce apoptotic effects in DPC. These data suggest that DPC from nonbalding scalp regions do have the capacity to undergo apoptosis, but need a high androgen stimulus. The present study provides an interesting new pathogenetic approach in androgenetic alopecia. Copyright (c) 2006 S. Karger AG, Basel.
PMID: 16931898 [PubMed - as supplied by publisher]
Finally,
I “sellâ€, acording to my theory, a totally free preventive method to avoid common hair loss. Allow grow scalp hair to a minimal length. Is so bad? Is it interferering the sales of finasteride, dutasteride, minoxidil, ketoconazole, pirictone olamine? I don’t think so.
And by the way, are you using anyone of the listed meds?, or better what is your prevention choice? Maybe dutasteride or MK8046?. Please note that I ask for a preventive method, not curative.
Armando