Yet another study disproving the donor dominance theory

SlowMoe

Member
Reaction score
0
http://www.ncbi.nlm.nih.gov/pubmed/16931898
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.
Source
Department of Dermatology and Allergy, Charité-Universitatsmedizin Berlin, Berlin, Germany.

Abstract
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.
 

Armando Jose

Senior Member
My Regimen
Reaction score
828
This is a important study, it was cited sometimes in this forum...

BTW, do you know others studies regarding this issue?

TIA
 

resu

Senior Member
Reaction score
1,376
So... in layman terms this means that even follicles from typical non-balding regions like the sides and the back can miniaturize as well if they're in a high androgen environment? I must be reading it wrong otherwise hair transplant wouldn't work.
 

SlowMoe

Member
Reaction score
0
SOME hair transplant hairs do miniaturize. Joe Rogan's implants are no more for instance.

Implants create new blood vessels when they are moved to balding regions. This allows more oxygen to reach the hair. However over time, in many instances, the environment degrades and the new blood vessels wither, resulting in miniaturized donor hairs.

Androgens typically only pose a threat where ther is a low oxygen condition, or where the dihydrotestosterone/ estradiol ratio gets out of wack, such as the galea.

- - - Updated - - -

[h=2]Treatment of Male Pattern Baldness with Botulinum Toxin: A Pilot Study[/h][h=3]Freund, Brian J. D.D.S., M.D.; Schwartz, Marvin D.D.S., M.Sc.
[/h]Free Access




Article Outline
[h=4]Author Information[/h]

Crown Institute; Pickering, Ontario, Canada
Correspondence to Dr. Freund, 49 Main Street South, Uxbridge, Ontario L9P 1J4, Canada, freund@crowninstitute.com
This clinical trial has been registered as “Treatment of Male Pattern Baldness with Botulinum Toxin” at http://www.clinicaltrials.gov/ClinicalTrials.gov with identifier NCT00965640.



Back to Top | Article Outline
[h=4]Sir:[/h]
Image Tools

We would like to present the results of an open-label pilot study using botulinum toxin type A (Botox; Allergan, Inc., Irvine, Calif.) for the treatment of androgenetic alopecia. This form of alopecia is believed to be caused by a genetically predisposed sensitivity of hair follicles to the toxic effects of dihydrotestosterone, a metabolite of testosterone. Medical treatment of androgenetic alopecia has previously only been moderately effective using systemic drugs such as finasteride, a 5α-reductase inhibitor.[SUP]1[/SUP]
In this ethically approved study, 50 male subjects aged between 19 and 57 years with Norwood/Hamilton ratings of II to IV participated.[SUP]2[/SUP] The study was 60 weeks in duration, with 12 weeks of run-in followed by two treatment cycles of 24 weeks each. Subjects were injected with 150 units of Botox (5 units per 0.1 ml saline) into the muscles surrounding the scalp, including frontalis, temporalis, periauricular, and occipitalis muscles in equally divided doses over 30 injection sites. The primary outcome measure was a change in hair count in a fixed 2-cm area using a method described by Canfield.[SUP]3[/SUP] Secondary outcome measures included hair loss, measured by having subjects collect loose hair from their pillow with a sticky lint roller, and subjective efficacy using a validated questionnaire. Statistical analysis entailed paired t tests of group means.
Forty subjects completed the study, and no adverse effects were reported. The treatment response rate was 75 percent. Mean hair counts for the entire group showed a statistically significant (p < 0.0001) increase of 18 percent between baseline and week 48 (Table 1), similar to the results reported with Propecia (Merck, Whitehouse Station, N.J.).[SUP]1[/SUP] Hair regrowth was objectively visible in some subjects (Fig. 1). Secondary outcome measures were also significantly improved. The reduction in hair loss and increase in hair count did not show a statistically significant correlation. This suggested that longer retention of terminal hairs did not account for the increase in hair count.

Table 1
Image Tools

Fig. 1
Image Tools

<TBODY>
</TBODY>


Mechanistically, the scalp behaves like a drum skin with tensioning muscles around the periphery. These muscle groups—the frontalis, occipitalis, and periauricular muscles and to a minor degree the temporalis—can create a “tight” scalp when chronically active. Because the blood supply to the scalp enters through the periphery, a reduction in blood flow would be most apparent at the distal ends of the vessels, specifically, the vertex and frontal peaks. Areas of the scalp with sparse hair growth have been shown to be relatively hypoxic, have slow capillary refill, and to have high levels of dihydrotestosterone.[SUP]4[/SUP]
Conceptually, Botox “loosens” the scalp, reducing pressure on the perforating vasculature, thereby increasing blood flow and oxygen concentration. The enzymatic conversion of testosterone to dihydrotestosterone is oxygen dependent. In low-oxygen environments, the conversion of testosterone to dihydrotestosterone is favored; whereas in high-oxygen environments, more testosterone is converted to estradiol.[SUP]4[/SUP] Blood flow may therefore be a primary determinant in follicular health. Strategically placed Botox injections appear able to indirectly modify this variable, resulting in reduced hair loss and new hair growth in some men with androgenetic alopecia.
 

IDW2BB

Established Member
Reaction score
19
If it was only about blood flow why even move hairs from the donor area? Why not just extract hair from recipient area and reinsert in the recipient area?
 

SlowMoe

Member
Reaction score
0
This would probably work actually, but the recipient area is where you need to add hairs, so you would be defeating the purpose lol
 

resu

Senior Member
Reaction score
1,376
How would this explain female hair loss? They have less testosterone than men yet the ones who bald, bald very diffusely on the sides, back and top.
 

SlowMoe

Member
Reaction score
0
How would this explain female hair loss? They have less testosterone than men yet the ones who bald, bald very diffusely on the sides, back and top.

Female hairloss typically occurs in the galea region, once they are exposed to DHT after menopause etc...
 

Armando Jose

Senior Member
My Regimen
Reaction score
828
What about sebum in the botox study?
I think that botox acts diminishing sebum (SER) due that muscle/nerve don´t drain the sebaceous gland.
 

SlowMoe

Member
Reaction score
0
^I'm not sure about that; only thing I know is botox is not injected into the balding areas but in the scalp muscles where hair is full, don't know how local the injections havet be to be effective
 

jake_b

Member
Reaction score
18
This would probably work actually, but the recipient area is where you need to add hairs, so you would be defeating the purpose lol

But if we're saying the transplant healing itself is the real reason transplanted follicles survive, not that there is anything special about the transplanted follicle itself ... it would seem you could increase the survival of hairs on the top of the head by "transplanting" them right back where they came from.
 
Top