What I find interesting is that placebo reduced scalp DHT levels by 13%.
If you remember the Goldman study concluded that DHT is overproduced locally due to low oxygen levels.
Perhaps the hope of a hair loss cure caused the placebo group to be under less stress, loosening their scalp and increasing bloodflow enough to inhibit DHT overproduction to an extent, especially since placebo was not noted to reduce serum DHT levels... Make sense to me..
The effects of finasteride on scalp skin and serum androgen levels in men with androgenetic alopecia.
Drake L, Hordinsky M, Fiedler V, Swinehart J, Unger WP, Cotterill PC, Thiboutot DM, Lowe N, Jacobson C, Whiting D, Stieglitz S, Kraus SJ, Griffin EI, Weiss D, Carrington P, Gencheff C, Cole GW, Pariser DM, Epstein ES, Tanaka W, Dallob A, Vandormael K, Geissler L, Waldstreicher J.
Source
University of Oklahoma Health Sciences, Oklahoma City, USA.
Abstract
BACKGROUND:
Data suggest that androgenetic alopecia is a process dependent on dihydrotestosterone (DHT) and type 2 5alpha-reductase. Finasteride is a type 2 5alpha-reductase inhibitor that has been shown to slow further hair loss and improve hair growth in men with androgenetic alopecia.
OBJECTIVE:
We attempted to determine the effect of finasteride on scalp skin and serum androgens.
METHODS:
Men with androgenetic alopecia (N = 249) underwent scalp biopsies before and after receiving 0.01, 0.05, 0.2, 1, or 5 mg daily of finasteride or placebo for 42 days.
RESULTS:
Scalp skin DHT levels declined significantly by 13.0% with placebo and by 14.9%, 61.6%, 56. 5%, 64.1%, and 69.4% with 0.01, 0.05, 0.2, 1, and 5 mg doses of finasteride, respectively. Serum DHT levels declined significantly (P <.001) by 49.5%, 68.6%, 71.4%, and 72.2% in the 0.05, 0.2, 1, and 5 mg finasteride treatment groups, respectively.
CONCLUSION:
In this study, doses of finasteride as low as 0.2 mg per day maximally decreased both scalp skin and serum DHT levels. These data support the rationale used to conduct clinical trials in men with male pattern hair loss at doses of finasteride between 0.2 and 5 mg.
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"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.4
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"
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In this study, you see that scalp DHT levels were 7.3 (balding) and 4.2 (non-balding); 43% higher in balding scalp
In the Goldman study scalp o2 levels were 32mmhg (balding) and 52mmhg (non-balding); 39% lower in balding scalp
So roughly 40% less oxygen = roughly 40% more DHT; very close correlation
Perhaps this would be a synchronous occurence; 30% less oxygen = 30% more DHT/ 5% less oxygen = 5% more DHT etc.....
The effect of finasteride, a 5 alpha-reductase inhibitor, on scalp skin testosterone and dihydrotestosterone concentrations in patients with male pattern baldness.
Dallob AL, Sadick NS, Unger W, Lipert S, Geissler LA, Gregoire SL, Nguyen HH, Moore EC, Tanaka WK.
Source
Merck Research Laboratories, Rahway, New Jersey 07065.
Abstract
The effects of the 5 alpha-reductase inhibitor, finasteride, on scalp skin testosterone (T) and dihydrotestosterone (DHT) levels were studied in patients with male pattern baldness. In a double blind study, male patients undergoing hair transplantation were treated with oral finasteride (5 mg/day) or placebo for 28 days. Scalp skin biopsies were obtained before and after treatment for measurement of T and DHT by high pressure liquid chromatography-RIA. In 10 male subjects studied at baseline, mean (+/- SEM) DHT levels were significantly higher in bald (7.37 +/- 1.24 pmol/g) compared to hair-containing (4.20 +/- 0.65 pmol/g) scalp, whereas there was no difference in mean T levels at baseline. In bald scalp from 8 patients treated with finasteride, the mean DHT concentration decreased from 6.40 +/- 1.07 pmol/g at baseline to 3.62 +/- 0.38 pmol/g on day 28. Scalp T levels increased in 6 of 8 subjects treated with finasteride. Finasteride decreased the mean serum DHT concentration from 1.36 +/- 0.18 nmol/L (n = 8) at baseline to 0.46 +/- 0.10 nmol/L on day 28 and had no effect on serum T. There were no significant changes in scalp or serum T or DHT in placebo-treated patients. In this study, male subjects treated with 5 mg/day finasteride for 4 weeks had significantly decreased concentrations of DHT in bald scalp, resulting in a mean level similar to the baseline levels found in hair-containing scalp.
If you remember the Goldman study concluded that DHT is overproduced locally due to low oxygen levels.
Perhaps the hope of a hair loss cure caused the placebo group to be under less stress, loosening their scalp and increasing bloodflow enough to inhibit DHT overproduction to an extent, especially since placebo was not noted to reduce serum DHT levels... Make sense to me..
The effects of finasteride on scalp skin and serum androgen levels in men with androgenetic alopecia.
Drake L, Hordinsky M, Fiedler V, Swinehart J, Unger WP, Cotterill PC, Thiboutot DM, Lowe N, Jacobson C, Whiting D, Stieglitz S, Kraus SJ, Griffin EI, Weiss D, Carrington P, Gencheff C, Cole GW, Pariser DM, Epstein ES, Tanaka W, Dallob A, Vandormael K, Geissler L, Waldstreicher J.
Source
University of Oklahoma Health Sciences, Oklahoma City, USA.
Abstract
BACKGROUND:
Data suggest that androgenetic alopecia is a process dependent on dihydrotestosterone (DHT) and type 2 5alpha-reductase. Finasteride is a type 2 5alpha-reductase inhibitor that has been shown to slow further hair loss and improve hair growth in men with androgenetic alopecia.
OBJECTIVE:
We attempted to determine the effect of finasteride on scalp skin and serum androgens.
METHODS:
Men with androgenetic alopecia (N = 249) underwent scalp biopsies before and after receiving 0.01, 0.05, 0.2, 1, or 5 mg daily of finasteride or placebo for 42 days.
RESULTS:
Scalp skin DHT levels declined significantly by 13.0% with placebo and by 14.9%, 61.6%, 56. 5%, 64.1%, and 69.4% with 0.01, 0.05, 0.2, 1, and 5 mg doses of finasteride, respectively. Serum DHT levels declined significantly (P <.001) by 49.5%, 68.6%, 71.4%, and 72.2% in the 0.05, 0.2, 1, and 5 mg finasteride treatment groups, respectively.
CONCLUSION:
In this study, doses of finasteride as low as 0.2 mg per day maximally decreased both scalp skin and serum DHT levels. These data support the rationale used to conduct clinical trials in men with male pattern hair loss at doses of finasteride between 0.2 and 5 mg.
- - - Updated - - -
"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.4
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"
- - - Updated - - -
In this study, you see that scalp DHT levels were 7.3 (balding) and 4.2 (non-balding); 43% higher in balding scalp
In the Goldman study scalp o2 levels were 32mmhg (balding) and 52mmhg (non-balding); 39% lower in balding scalp
So roughly 40% less oxygen = roughly 40% more DHT; very close correlation
Perhaps this would be a synchronous occurence; 30% less oxygen = 30% more DHT/ 5% less oxygen = 5% more DHT etc.....
The effect of finasteride, a 5 alpha-reductase inhibitor, on scalp skin testosterone and dihydrotestosterone concentrations in patients with male pattern baldness.
Dallob AL, Sadick NS, Unger W, Lipert S, Geissler LA, Gregoire SL, Nguyen HH, Moore EC, Tanaka WK.
Source
Merck Research Laboratories, Rahway, New Jersey 07065.
Abstract
The effects of the 5 alpha-reductase inhibitor, finasteride, on scalp skin testosterone (T) and dihydrotestosterone (DHT) levels were studied in patients with male pattern baldness. In a double blind study, male patients undergoing hair transplantation were treated with oral finasteride (5 mg/day) or placebo for 28 days. Scalp skin biopsies were obtained before and after treatment for measurement of T and DHT by high pressure liquid chromatography-RIA. In 10 male subjects studied at baseline, mean (+/- SEM) DHT levels were significantly higher in bald (7.37 +/- 1.24 pmol/g) compared to hair-containing (4.20 +/- 0.65 pmol/g) scalp, whereas there was no difference in mean T levels at baseline. In bald scalp from 8 patients treated with finasteride, the mean DHT concentration decreased from 6.40 +/- 1.07 pmol/g at baseline to 3.62 +/- 0.38 pmol/g on day 28. Scalp T levels increased in 6 of 8 subjects treated with finasteride. Finasteride decreased the mean serum DHT concentration from 1.36 +/- 0.18 nmol/L (n = 8) at baseline to 0.46 +/- 0.10 nmol/L on day 28 and had no effect on serum T. There were no significant changes in scalp or serum T or DHT in placebo-treated patients. In this study, male subjects treated with 5 mg/day finasteride for 4 weeks had significantly decreased concentrations of DHT in bald scalp, resulting in a mean level similar to the baseline levels found in hair-containing scalp.
