Hair follicles contain 2 forms of ATP-sensitive K-channels

[bornthisway]

Human hair follicles contain two forms of ATP-sensitive potassium channels, only one of which is sensitive to minoxidil.
FASEB J. 2008 Feb 7

Katie Shorter, Nilofer P. Farjo, Steven M. Picksley, and Valerie A. Randall

E-mail contact: v.a.randall@bradford.ac.uk

Department of Biomedical Sciences, University of Bradford, Bradford, UK; and Farjo Medical Centre, Manchester, UK.

Hair disorders cause psychological distress but are generally poorly controlled; more effective treatments are required. Despite the long-standing use of minoxidil for balding, its mechanism is unclear; suggestions include action on vasculature or follicle cells. Similar drugs also stimulate hair, implicating ATP-sensitive potassium (KATP) channels. To investigate whether KATP channels are present in human follicles, we used organ culture, molecular biological, and immunohistological approaches. Minoxidil and tolbutamide, a KATP channel blocker, opposed each other's effects on the growing phase (anagen) of scalp follicles cultured in media with and without insulin. Reverse transcriptase-polymerase chain reaction identified KATP channel component gene expression including regulatory sulfonylurea receptors (SUR) SUR1 and SUR2B but not SUR2A and pore-forming subunits (Kir) Kir6.1 and Kir6.2. When hair bulb tissues were examined separately, epithelial matrix expressed SUR1 and Kir6.2, whereas both dermal papilla and sheath exhibited SUR2B and Kir6.1. Immunohistochemistry demonstrated similar protein distributions. Thus, human follicles respond biologically to KATP channel regulators in culture and express genes and proteins for two KATP channels, Kir6.2/SUR1 and Kir6.1/SUR2B; minoxidil only stimulates SUR2 channels. These findings indicate that human follicular dermal papillae contain KATP channels that can respond to minoxidil and that tolbutamide may suppress hair growth clinically; novel drugs designed specifically for these channels could treat hair disorders.-Shorter, K., Farjo, N. P., Picksley, S. M., Randall, V. A. Human hair follicles contain two forms of ATP-sensitive potassium channels, only one of which is sensitive to minoxidil.

PMID: 18258787 [PubMed - as supplied by publisher]

 

[bornthisway]

Which explains why topical B12 and minoxidil are more effective.
Topical B12 alone seems to have a beneficial effect on hair.

'Our new topical trial of vitamin B12 will be helpful treatment for alopecia as a single dose or coadministraition with minoxidil though the precise mechanism was not elucidated.'

---

From the European Hair Research Society (EHRS) Conference (2006 London)

http://www.ehrs.org/conferenceabstracts ... 4-park.htm

Topical administration of cyanocobalamin (vitamin B12) showed suppression of potassium channel inhibitor (tolbutamide) and induction of murine hair anagen phase & synergistic effect with minoxidil

Author: Nok-Hyun Park (N.-H. Park)

Skin Research Team, Amore Pacific Corporation R&D Center, South Korea.

Vitamin B12 is well known to be important for growth, cell reproduction, blood formation, and protein & tissue synthesis. Cyanocobalamin and hydroxocobalamin acetate are used to treat pernicious anemia, nutritional vitamin B12 deficiency, malabsorption of vitamin B12, and other cases of vitamin B12 deficiency.

We investigated the active effect of vitaminB12 on NIH3T3 fibroblast in ATP-sensitive potassium channel-dependent fashion and on murine anagen indution.

The in vitro effects of established potassium channel openers (minoxidil) and inhibitors (tolbutamide), plus vitamin B12 were indirectly assessed on NIH3T3 fibroblast in the absence of aminoglycoside antibiotics & phenol red, and 5% fetal bovine serum-supplemented medium.

Tolbutamide inhibited 28% proliferation of NH3T3 fibroblast at 2.5mM concentration as reported previously.

When minoxidil & cyanocobalamin was treated to the fibroblast with 2.5mM tolbutamide, growth inhibition of NIH3T3 fibroblast was suppressed 51.49% by 100uM minoxidil 38.39% by 1uM cyanocobalamin, respectively.

Two topical preparations of single dose of minoxidil (1%) and cyanocobalamin (0.03%) were topically administered with vehicle (ethanol/ propylene glycol/ water= 3/ 2/ 5) on clipped dorsal area of female telogen phase C57bl/6.

The grown hair weights of topical 1% minoxidil preparation (113.14¡¾11.02mg, P<0.001) and 0.03% cyanocobalamin (59.56¡¾13.88mg, P<0.05) increased significantly than that of vehicle (18.47¡¾4.68mg).

When topically administered in mixed preparations (0.5% minoxidil and 0.03% cyanocobalamin), the more grown hair weight (87.00¡¾8.39mg, P<0.03 t-test with 0.05% minoxidil) by mixed preparation was observed compared to those of single 0.5% minoxidil preparation (44.33¡¾14.96mg) & of vehicle preparation (22.13¡¾13.86mg).

Topical cyanocobalamin was applied to atopic dermatitis and psoriasis in previous study; our new topical trial of vitamin B12 will be helpful treatment for alopecia as a single dose or coadministraition with minoxidil though the precise mechanism was not elucidated.

 

[harold]

Wow - I had seen that b12 was effective as an adjunct to minoxidil but I can see now that it seems to be more effective than the somewhat borderline difference I thought it made. Though of course it is hard to judge given the concentrations used and trying to compare them to your standard 5% 2mls a day routine.
hh

 

[Armando Jose]

Bornthis way, you are a crack,

Who is the author of these studies?

Curiously, my topical product contains also Vit B12, apart others products as grape seed extract, aloe vera, etc.

Armando

 

[bornthisway]

Bornthis way, you are a crack,

Who is the author of these studies?

Curiously, my topical product contains also Vit B12, apart others products as grape seed extract, aloe vera, etc.

Armando

Thanks, I think.
I updated the two studies with all relevant info I could find, date, names, locations, etc.

Sinere also include it in their product -- they also go into the why for other ingredients they include. http://www.sinere.com/nanominox_en.html

Basically.. if tolbutamide can suppress hair growth, and if topical B12 suppresses tolbutamide.. then it's just another tool we can use to manage hair loss. An ECGC+B12 topical would be simple and cheap to formulate.. adenosine and B12 would be complimentary too but acquiring adenosine may be harder or costly (or annoying, crushing tablets).. using minoxidil may be simpler for some over adenosine.

As for it being in your product, all those components likely play roles in assisting with hair loss. If it were cost effective for me I'd try it out, but I am in the U.S. as well. I'll probably experiment w/ ECGC+B12 and likely RK soon.

 

[Armando Jose]

Yeah,

Valerie Randall and Nok-Hyun Park, Skin Research Team, Amore Pacific Corporation R&D Center, South Korea.

Thank you and good luck

Armando

BTW, in your firm apears S. Foote, a good guy.