Hair Loss Blog
Dr Proctor's Hair Loss Blog
A new formulation of minoxidil
Lee HJ1, et al, Preparation and in vivo evaluation of lecithin-based
microparticles for topical delivery of minoxidil.
Arch Pharm Res. 2017 Aug 2. doi: 10.1007/s12272-017-0934-x
Abstract: Minoxidil is widely used for treatment of male pattern hair loss.
Commercial products containing minoxidil are usually in solution form.
Repeated applications of minoxidil solution can lead to adverse
effects such as skin irritation and horniness. The aims of this
study were to prepare lecithin-based microparticle in minoxidil
solution for enhancement of minoxidil topical delivery and skin
protection and evaluate the ability of lecithin on in vitro
delivery, in vivo hair growth, and skin trouble improvement
compared to commercial minoxidil solution. In in vitro skin
permeation study, minoxidil solution containing lecithin
microparticle showed higher skin penetration rate and higher
retention of drug inside the skin compared to minoxidil solution
without lecithin. After topical application of minoxidil solutions
with or without lecithin to C57BL/6 mice, minoxidil 5% solution
containing lecithin microparticle showed hair re-growth as
efficient as commercial product of minoxidil 5% solution.
It also significantly improved skin troubles while commercial
product presented horny substance and crust formation. Therefore,
the lecithin-based microparticle in minoxidil 5% solution
has good ability to promote hair growth without adverse effects.
A review of some hair loss treatment methods.
Adil A1, Godwin M2.The effectiveness of treatments for androgenetic alopecia: A systematic review and meta-analysis. J Am Acad Dermatol. 2017 Apr 7. pii: S0190-9622(17)30306-7. doi: 10.1016/j.jaad.2017.02.054.
Abstract: Androgenetic alopecia, or male pattern hair loss, is a hair loss disorder mediated by dihydrotestosterone, the potent form of testosterone. Currently, minoxidil
and finasteride are Food and Drug Administration (FDA)-approved, and HairMax LaserComb, which is FDA-cleared, are the only treatments recognized by the FDA as treatments of androgenetic alopecia.
This systematic review and meta-analysis assesses
the efficacy of nonsurgical treatments of androgenetic
alopecia in comparison to placebo for improving hair
density, thickness, growth (defined by an increased
anagen:telogen ratio), or subjective global assessments
done by patients and investigators.
A systematic review of randomized controlled trials was conducted.
PubMed, Embase, and Cochrane were searched up to December 2016,
with no lower limit on the year. We included only randomized
controlled trials of good or fair quality based on the US
Preventive Services Task Force quality assessment process.
A meta-analysis was conducted separately for 5 groups of
studies that tested the following hair loss treatments:
low-level laser light therapy in men, 5% minoxidil in men,
2% minoxidil in men, 1 mg finasteride in men, and 2%
minoxidil in women. All treatments were superior to
placebo in the 5 meta-analyses
CONCLUSIONS: This meta-analysis strongly suggests that
minoxidil, finasteride, and low-level laser light
therapy are effective for promoting hair growth in
men with androgenetic alopecia and that minoxidil
is effective in women with androgenetic alopecia.
Another paper on possible sexual dysfunction with Finasteride (Propecia).
"Persistent Sexual Side Effects of Finasteride (Propecia) for Male Pattern Hair Loss," Irwig, Michael S. et al.
The Journal of Sexual Medicine , Volume 8 , Issue 6 , 1747 - 1753
ABSTRACT: Finasteride has been associated with reversible adverse
sexual side effects in multiple randomized, controlled trials for the
treatment of male pattern hair loss (MPHL). The Medicines and Healthcare
Products Regulatory Agency of the United Kingdom and the Swedish
Medical Products Agency have both updated their patient information
leaflets to note that “persistence of erectile
dysfunction after discontinuation of treatment with Propecia
has been reported in post-marketing use.”
Aim: We sought to characterize the types and duration of persistent
sexual side effects in otherwise healthy men who took finasteride for MPHL (Male Pattern Hair Loss).
Methods: We conducted standardized interviews with 71 otherwise
healthy men aged 21–46 years who reported the new onset of sexual
side effects associated with the temporal use of finasteride, in
which the symptoms persisted for at least 3 months despite the discontinuation of finasteride.
Main Outcome Measures: The types and duration of sexual
dysfunction and the changes in perceived sexual frequency
and sexual dysfunction score between pre- and post-finasteride use.
Results: Subjects reported new-onset persistent sexual
dysfunction associated with the use of finasteride: 94%
developed low libido, 92% developed erectile dysfunction,
92% developed decreased arousal, and 69% developed problems with
orgasm. The mean number of sexual episodes per month dropped and
the total sexual dysfunction score increased for before and after
finasteride use according to the Arizona Sexual Experience Scale.
The mean duration of finasteride use was 28 months and the mean
duration of persistent sexual side effects was 40 months from the
time of finasteride cessation to the interview date. Study
limitations include a post hoc approach, selection bias, recall
bias for before finasteride data, and no serum hormone levels.
Conclusion: Physicians treating MPHL should discuss the potential
risk of persistent sexual side effects associated with finasteride.
Slightly-edited for Blog use
Dr P notes-- more on ATK-activation and hair regrowth.
Effect of sinapic acid on hair regrowth in human hair follicle dermal papilla cells via Akt activation.
Woo H1, et al.Arch Dermatol Res. 2017 Mar 20. doi: 10.1007/s00403-017-1732-5
Hair loss also or alopecia is caused by abnormal hair follicle cycling including shortening of the anagen (growth)
phase and changing of hair follicle morphology with miniaturization. In accordance with the life extension,
the quality of life is considered to be a most important thing. The yearning for healthy and beautiful hair
and low self esteem due to hair loss had negative influence on the quality of life with psychosocial maladjustment.
The objective of this research was to identify new compound that can be used as a drug to promote hair growth.
We investigated whether the function of sinapic acid (SA) is able to promote hair growth in human
hair follicle dermal papilla cells (hHFDPC). We showed that treatment of SA in hHFDPC could induce
proliferation and the activation of Akt signaling in HFDPC. In addition, SA could stimulate the
expressions of the several growth factors, insulin-like growth factor 1, and vascular endothelial
growth factor for hair growth. We showed that SA led to an increased level of phospho-GSK-3β
and β-catenin accumulation in HFDPC. Finally, the promoting effect of SA in hHFDPC cell growth
occurred by the induction of cell cycle progression. These results suggest that SA could
be one of the potential candidate compounds for the treatment of alopecia by inducing hair regrowth
through triggering the expressions of growth factors via activation of Akt and subsequent inactivation of
GSK-3β /β-catenin pathway.
Dr Proctor sez: Intersting paper on using low-level red light to treat hair loss.
Friedman S, Schnoor P.,Novel Approach to Treating Androgenetic
Alopecia in Females With Photobiomodulation (Low-Level Laser Therapy).
Dermatol Surg. 2017 Mar 21. doi: 10.1097/DSS.0000000000001114.
BACKGROUND: Photobiomodulation, also referred to as low-level
laser therapy (LLLT),is used for the promotion of hair regrowth.
To better clarify the effects on the human hair
follicle and surrounding tissue structures of laser light
at 650 nm. ow-level laser treatment of the scalp every
other day for 17 weeks is a safe and
effective treatment for androgenetic alopecia in healthy females with Ludwig-Savin
Baldness Scale I-2 to II-2 baldness patterns. Subjects receiving LLLT at
650 nm achieved an increase in hair counts compared with sham-treated
control patients in this multicenter randomized controlled trial.
low-level laser therapy may play a potentially significant role in health
care providers' armamentarium for androgenic alopecia or male pattern hairloss.. (edited for blog use)
Arif T1, et al, Dutasteride in androgenetic alopecia: An update. Curr Clin Pharmacol. 2017 Mar 10. doi: 10.2174/1574884712666170310111125.
BACKGROUND:Androgenetic alopecia is a common condition characterized by thinning of scalp hair. Conversion of testosterone to dihydrotestosterone, a more potent androgen, by the enzyme 5-a-reductase is responsible for underlying pathogenesis. Dutasteride, a synthetic 4-azasteroid, is a selective and competitive inhibitor of both type-1 and type-2 isoenzymes of 5-alpha-reductase. Finasteride and minoxidil are the only approved drugs for androgenetic alopecia. Dutasteride has been demonstrated to be effective in several randomized, double-blind, placebo controlled trials in androgenetic alopecia. In this review, after the pharmacology of dutasteride, the authors have discussed the status of dutasteride in androgenetic alopecia and has compared its efficacy with that of finasteride.
OBJECTIVE:This article aims to review the current status of dutasteride in androgenetic alopecia. The structure, mechanism of action, pharmacokinetic and side effects are discussed along with its comparission with finasteride in androgenetic alopecia.
One of our agents, Tempol, inhibits JAK-STAT signaling.
This may account for at least some of its effectiveness in hair loss treatment.
McCormick J1, et al, "Free radical scavenging inhibits STAT phosphorylation following in
vivo ischemia/reperfusion injury.", FASEB J. 2006 Oct;20(12):2115-7.
The signal transducer and activator of transcription (STAT
family are latent transcription factors involved in a variety
of signal transduction pathways, including cell death cascades.
STAT1 has been shown to have a crucial role in regulating cardiac
cell apoptosis in the myocardium exposed to ischemia/reperfusion
(I/R) injury. The free radical scavenger, tempol, is known to have
cardioprotective properties, although little is known about the
molecular mechanism(s) by which it acts. In the present study, we
assessed the levels of phosphorylated STAT1 and STAT3 and examined
whether tempol was able to affect STAT activation after in vivo
cardiac I/R injury. We observed a reperfusion time-dependent increase
in the tyrosine phosphorylation of STAT1 and STAT3 at residues 701 and
705, respectively. Here we show for the first time that tempol
dramatically reduced STAT1 and 3 phosphorylation. The reduction in
STAT1 and 3 phosphorylation was accompanied by a concomitant decrease in
cellular malondialdehyde (MDA) levels. To verify the role of STAT1 in
modulating the cardioprotective effect of tempol, rats were injected
with the STAT1 activator, IFN-gamma, and tempol during I/R injury. We
found that the presence of IFN-gamma abrogated the protective effects
of tempol, suggesting that the protective effects of tempol may partly
operate by decreasing the phosphorylation of STAT1. This study
demonstrates that careful dissection of the molecular mechanisms that
underpin I/R injury may reveal cardioprotective targets for future therapy.
Harel, S. et al, "Pharmacologic inhibition of JAK-STAT signaling promotes hair growth."
Sci Adv. 2015 Oct 23;1(9):e1500973. doi: 10.1126/sciadv.1500973
Abstract: Several forms of hair loss in humans are characterized by the inability of hair
follicles to enter the growth phase (anagen) of the hair cycle after being
arrested in the resting phase (telogen). Current pharmacologic therapies have
been largely unsuccessful in targeting pathways that can be selectively modulated
to induce entry into anagen. We show that topical treatment of mouse and human
skin with small-molecule inhibitors of the Janus kinase (JAK)-signal transducer
and activator of transcription (STAT) pathway results in rapid onset of anagen
and subsequent hair growth. We show that JAK inhibition regulates the activation
of key hair follicle populations such as the hair germ and improves the
inductivity of cultured human dermal papilla cells by controlling a molecular
signature enriched in intact, fully inductive dermal papillae. Our findings open
new avenues for exploration of JAK-STAT inhibition for promotion of hair growth
and highlight the role of this pathway in regulating the activation of hair
follicle stem cells.
Dr Proctor sez-- Papers on on PRP (Platelet-Rich Plasma)
Treatment of Hair loss.
By Moustafa A. et al, "Platelets Rich Plasma Versus Minoxidil 5%
in Treatment of Alopecia Areata: A Trichoscopic Evaluation", October 28, 2016
Abstract: Alopecia areata is a common cause of nonscarring alopecia
that occurs in a patchy, confluent, or diffuse pattern. Dermoscopy is a
noninvasive technique for the clinical diagnosis of many skin diseases.
Topical minoxidil solution 5% and platelet rich plasma are important
modalities used in treatment of alopecia areata. We aimed to evaluate
the efficacy of PRP versus topical minoxidil 5% in the treatment of
AA by clinical evaluation and trichoscopic examination. Ninety patients
were allocated into three groups; the first was treated with topical
minoxidil 5% solution, the second with platelets rich plasma injections,
and the third with placebo. Diagnosis and follow up were done by
serial digital camera photography of lesions and dermoscopic scan
before and every 1 month after treatment for 3 months. Patients
treated with minoxidil 5% and platelets rich plasma both have significant
hair growth than placebo. Patients treated with platelets
rich plasma had an earlier response in the form of hair regrowth,
reduction in short vellus hair and dystrophic hair unlike patients
treated with minoxidil and control In conclusion, platelets rich plasma
is more effective in the treatment of alopecia areata than topical
minoxidil 5% as evaluated by clinical and trichoscopic examination.
Gupta AK, Carviel J., A Mechanistic Model of Platelet-Rich
Plasma Treatment for Androgenetic Alopecia.Dermatol Surg. 2016 Sep 14.
BACKGROUND: Platelet-rich plasma (PRP) therapy is a novel procedure used to treat
androgenetic alopecia (AGA).
OBJECTIVE: Propose a mechanism of action of PRP therapy for AGA.
METHODS AND MATERIALS: A thorough literature search including PRP research for
AGA therapy as well as PRP research in other areas of medicine was conducted.
RESULTS: A mechanistic model for the action of PRP on the hair follicle was
CONCLUSION: Platelet-rich plasma therapy stimulates hair growth through the
promotion of vascularization and angiogenesis, as well as encourages hair
follicles to enter and extend the duration of the anagen phase of the growth
cycle. The process is accomplished through growth factor-mediated increased
activation of wingless (Wnt)/β-catenin, extracellular signaling regulated kinase
(ERK), and protein kinase B (Akt) signaling pathways, which leads to the
necessary cellular proliferation and differentiation.
Tempol and JAK kinases
Recently, medical researchers discovered that JAK kinase inhibitors such as Ruxolitinib
and Tofacitinib are hair growth stimulators. As this paper shows, Tempol likewise modulates the action of JAK kinases. Tempol
is in all our products and is a much safer agent.
Banday AA1, Lokhandwala MF. Oxidative stress causes renal angiotensin II type 1 receptor upregulation,
Na+/H+ exchanger 3 overstimulation, and hypertension.
Hypertension. 2011 Mar;57(3):452-9.
doi: 10.1161/HYPERTENSIONAHA.110.162339. Epub 2011 Jan 31.
Abstract Oxidative stress modulates angiotensin (Ang) II type 1
receptor (AT(1)R) expression and function. Ang II activates renal Na(+)/H(+)
exchanger 3 (NHE3) to increase sodium reabsorption, but the mechanisms are still
elusive. In addition, the upregulation of AT(1)R during oxidative stress could
promote sodium retention and lead to an increase in blood pressure. Herein,
we investigated the mechanism of Ang II-mediated, AT(1)R-dependent renal NHE3
regulation and effect of oxidative stress on AT(1)R signaling and development of
hypertension. Male Sprague-Dawley rats received tap water (control) or 30 mmol/L
of l-buthionine-sulfoximine, an oxidant, with and without 1 mmol/L of Tempol,
an antioxidant, for 3 weeks. l-Buthionine-sulfoximine-treated rats exhibited
oxidative stress and high blood pressure. Incubation of renal proximal tubules
with Ang II caused significantly higher NHE3 activation in
l-buthionine-sulfoximine-treated rats compared with control. The activation
of NHE3 was sensitive to AT(1)R blocker and inhibitors of phospholipase C,
tyrosine kinase, janus kinase 2 (Jak2), Ca(2+)-dependent calmodulin (CaM),
and Ca(2+) chelator. Also, incubation of proximal tubules with Ang II caused
Jak2-dependent CaM phosphorylation, which led to Jak2-CaM complex formation
and increased Jak2-CaM interaction with NHE3. The activation of these
signaling molecules was exaggerated in l-buthionine-sulfoximine-treated
rats, whereas Tempol normalized the AT(1)R signaling. In conclusion,
Ang II activates renal proximal tubular NHE3 through novel pathways that
involve phospholipase C and an increase in intracellular Ca(2+), Jak2, and CaM.
In addition, oxidative stress exaggerates Ang II signaling, which leads to
overstimulation of renal NHE3 and contributes to an increase in blood pressure.
DR P sez: Note how TEMPOL, used in our hair loss treatment formulation,
"restored hair cycle"
Liu N, et al, Chronic Restraint Stress Inhibits Hair
Growth via Substance P Mediated by Reactive Oxygen Species in Mice.
PLoS One. 2013 Apr 26;8(4):e61574. doi: 10.1371/journal.pone.0061574. Print 2013.
BACKGROUNDS: Solid evidence has demonstrated that psychoemotional stress
induced alteration of hair cycle through neuropeptide substance P (SP)
mediated immune response, the role of reactive oxygen species (ROS) in
brain-skin-axis regulation system remains unknown.
OBJECTIVES: The present study aims to investigate possible mechanisms
of ROS in regulation of SP-mast cell signal pathway in chronic restraint
stress (CRS, a model of chronic psychoemotional stress) which induced
abnormal of hair cycle.
METHODS AND RESULTS:Our results have demonstrated that CRS
actually altered hair cycle by inhibiting hair follicle growth
in vivo, prolonging the telogen stage and delaying subsequent
anagen and catagen stage. Up-regulation of SP protein expression
in cutaneous peripheral nerve fibers and activation of mast cell
were observed accompanied with increase of lipid peroxidation levels
and reduction of the activities of superoxide dismutase (SOD)
and glutathione peroxidase (GSH-Px) in CRS mice skin. In addition,
SP receptor antagonist (RP67580) reduced mast cell activations and
lipid peroxidation levels as well as increased GSH-Px activity and
normalized hair cycle. Furthermore, antioxidant Tempol (a free
radical scavenger) also restored hair cycle, reduced SP protein
expression and mast cell activation.
Our study provides the first solid evidence for how ROS play a
role in regulation of psychoemotional stress induced SP-Mast cell
pathway which may provide a convincing rationale for antioxidant
application in clinical treatment with psychological stress induced hair loss.
G. Douauda, et al, Preventing Alzheimer's disease-related gray matter
atrophy by B-vitamin treatment, PNAS, vol. 110 no. 23, 9523–9528
Abstract: Is it possible to prevent atrophy of key brain regions
related to cognitive decline and Alzheimer's disease (AD)? One approach
is to modify nongenetic risk factors, for instance by lowering elevated
plasma homocysteine using B vitamins. In an initial, randomized
controlled study on elderly subjects with increased dementia risk (mild
cognitive impairment according to 2004 Petersen criteria), we showed
that high-dose B-vitamin treatment (folic acid 0.8 mg, vitamin B6 20 mg,
vitamin B12 0.5 mg) slowed shrinkage of the whole brain volume over 2 y.
Here, we go further by demonstrating that B-vitamin treatment reduces,
by as much as seven fold, the cerebral atrophy in those gray matter
(GM) regions specifically vulnerable to the AD process, including the
medial temporal lobe. In the placebo group, higher homocysteine levels
at baseline are associated with faster GM atrophy, but this deleterious
effect is largely prevented by B-vitamin treatment. We additionally
show that the beneficial effect of B vitamins is confined to
participants with high homocysteine (above the median, 11 µmol/L)
and that, in these participants, a causal Bayesian network analysis
indicates the following chain of events: B vitamins lower homocysteine,
which directly leads to a decrease in GM atrophy, thereby slowing
cognitive decline. Our results show that B-vitamin supplementation can
slow the atrophy of specific brain regions that are a key component of
the AD process and that are associated with cognitive decline.
Further B-vitamin supplementation trials focusing on elderly subjets
with high homocysteine levels are warranted to see if progression to
dementia can be prevented.
Catalase and graying hair
We are getting questions about recent media reports of the use of
catalase and pseudocatalase to prevent hair from greying.
Briefly: Hydrogen peroxide produced in metabolism prevents the production of
the pigment melanin and make hair turn grey. Agents such as catalase itself or with catalase-like
activity (pseudocatalase) such as PC-KUS destroy
hydrogen peroxide and thus prevent hair from turning gray.
This is not exactly new information. Dr Proctor is a world-recognized expert on melanin
pigment and on catalase. In fact, Dr Proctor published papers on the experimental
use of catalase as medical treatment nearly three decades ago and is a pioneer in this field.
Similarly, part of our experimental apparatus in melanin research is in the Smithsonian Institution's
American Museum of History collection of pioneering items in semiconductor science. See:
Thus, we have long added agents which block
the inhibitory action of hydrogen
peroxide and other "active oxygen species" on hair pigmentation and hair graying.
This includes "pseudocatalases".
And yes, our agents do inhibit graying of hair. However,
if gray hair and not hair loss
is your only consideration, arguably, the best thing is just to dye it.
Shah AA, Sinha AA., Oxidative stress and autoimmune skin disease.
Eur J Dermatol. 2013 Feb 1;23(1):5-13. doi: 10.1684/ejd.2012.1884.
antioxidants play the important role in our body of neutralizing free radicals
and peroxides that are formed during normal physiologic events. While these
reactive oxygen species are necessary for numerous biological processes,
when created in excess they can have deleterious effects. The skin as an
organ is constantly under attack by reactive oxygen species from both
endogenous and exogenous sources. The pathophysiology of many autoimmune
diseases is unknown and recently oxidative stress has come to light as a
possible triggering mechanism. Recent investigations attempting to link
autoimmune skin diseases and oxidative stress have had varying degrees of
success. In this article, we review the current literature regarding
antioxidants in hair loss due to alopecia areata, pemphigus vulgaris and other
blistering diseases, vitiligo, and psoriasis, and suggest
possible future studies and treatment options.
KEYWORDS: alopecia areata, antioxidant, autoimmune, free radicals, catalase,
psudocatalase,oxidative stress, pemphigus vulgaris, reactive oxygen species,
organic semiconductors, vitiligo,gray, grey, graying, PC-KUS
Rasheed H,et al, Serum Ferritin and Vitamin D in Female Hair Loss: Do They Play a Role?.
Skin Pharmacol Physiol. 2013 Feb 20;26(2):101-107.
Evaluation of serum ferritin and vitamin D levels in females with chronic
telogen effluvium (TE) or female pattern hair loss (FPHL), in order to validate
their role in these common hair loss diseases. Methods: Eighty females
(18 to 45 years old) with hair loss, in the form of TE or FPHL, and 40
age-matched females with no hair loss were included in the study.
Diagnosis was based upon clinical examination as well as trichogram
and dermoscopy. Serum ferritin and vitamin D(2) levels were determined
for each participant. Results: Serum ferritin levels in the TE
(14.7 ± 22.1 μg/l) and FPHL (23.9 ± 38.5 μg/l) candidates were
significantly lower than in controls (43.5 ± 20.4 μg/l). Serum
vitamin D(2) levels in females with TE (28.8 ± 10.5 nmol/l) and FPHL
(29.1 ± 8.5 nmol/l) were significantly lower than in controls
(118.2 ± 68.1 nmol/l; p < 0.001). These levels decreased with
increased disease severity. Serum ferritin cut-off values for
TE and FPHL were 27.5 and 29.4 μg/l, respectively, and those
for vitamin D were 40.9 and 67.9 nmol/l. Conclusion: Low serum
ferritin and vitamin D(2) are associated with hair loss in females
with TE and FPHL. Screening to establish these levels in cases of
hair loss and supplementing with them when they are deficient may
be beneficial in the treatment of disease.
Dr Proctor comments on the following paper: We hold the primary patents for TEMPOL
and use it in our hair loss treatment formulations. As the abstract below reports,
part of its efficacy may be that it prevents pathological increases
in the numbers of androgen receptors and thus
makes antiandrogens work longer and better. We long-ago discovered that
TEMPOL works in hair loss treatment. Preventing tissue reflex hyperandrogenicity
is an unexpected bonus that may partially explian why TEMPOL seems to work so well
as part of combination treatment:
Thomas R, Sharifi N., SOD mimetics: a novel class of androgen receptor
inhibitors that suppresses castration-resistant growth of prostate cancer,
Mol Cancer Ther. 2012 Jan;11(1):87-97. Epub 2011 Dec 15
Abstract: Advanced prostate cancer is the second leading cause of
cancer-related deaths among American men. The androgen receptor (AR)
is vital for prostate cancer progression, even in the face of castrate
levels of serum testosterone following androgen ablation therapy, a
mainstay therapy for advanced prostate cancer. Downregulation of
superoxide dismutase 2 (SOD2), a major intracellular antioxidant
enzyme, occurs progressively during prostate cancer progression
to advanced states and is known to promote AR activity in prostate
cancer. Therefore, this study investigated the effects of SOD mimetics
on AR expression and function in AR-dependent LNCaP, CWR22Rv1, and
LAPC-4AD prostate cancer cells. Treatment with Tempol
(4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl), a SOD mimetic,
not only lowered cellular superoxide levels but also concomitantly
attenuated AR transcriptional activity and AR target gene expression
in a dose- and time-dependent manner, in the presence and absence of
dihydrotestosterone, the major endogenous AR agonist. Inhibition of
AR by Tempol was mediated, in large part, by its ability to decrease
AR protein via increased degradation, in the absence of any inhibitory
effects on other nuclear receptors. Inhibitory effects of Tempol on
AR were also reproducible with other SOD mimetics, MnTBAP and MnTMPyP.
Importantly, effects of Tempol on AR function were accompanied by
significant in vitro and in vivo reduction in castration-resistant
prostate cancer (CRPC) survival and growth. Collectively, this study
has shown for the first time that SOD mimetics, by virtue of their
ability to suppress AR function, may be beneficial in treating the
currently incurable CRPC, in which SOD2 expression is highly suppressed.
The role of inflammation and immunity in the pathogenesis of androgenetic
CM, Rossi A, Poe J, Manhas-Bhutani S, Sadick
Background: Female pattern hair loss
affects many women; its pathogenetic basis has been held to be
similar to men with common baldness. Objective: The objective of this
study was to determine the role of immunity and inflammation in
androgenetic alopecia in women and modulate therapy according to
inflammatory and immunoreactant profiles. Materials and Methods: 52
women with pattern hair loss (AA) underwent scalp biopsies for
microscopic assessment and immunofluroescent studies. In 18 patients,
serologic assessment for antibodies to androgen receptor, estrogen
receptor and cytokeratin 15 was conducted. Results: A lymphocytic
folliculitis targeting the bulge epithelium was observed in many
cases. Thirty-three of 52 female patients had significant deposits of
IgM within the epidermal basement membrane zone typically accompanied
by components of complement activation. The severity of changes light
microscopically were more apparent in the positive immunoreactant
group. Biopsies from men with male pattern hair loss showed a similar
pattern of inflammation and immunoreactant deposition. Serologic
assessment for antibodies to androgen receptor, estrogen receptor or
cytokeratin 15 were negative. Combined modality therapy with
minocycline and topical steroids along with red light produced
consistent good results in the positive immunoreactant group compared
to the negative immunoreactant group. Conclusion: A lymphocytic
microfolliculitis targeting the bulge epithelium along with deposits
of epithelial basement membrane zone immunoreactants are frequent
findings in male pattern hairloss and could point toward an
immunologically driven trigger. Cases showing a positive
immunoreactant profile respond well to combined modality therapy
compared to those with a negative result.
J Drugs Dermatol.
extract for Hair Loss treatment
Dr Proctor notes: There have long been reports
that gensing extract has some hair loss treatment efficacy.
Ethnopharmacol. 2011 Sep 21. [Epub ahead of print]
panax ginseng extract promotes hair regeneration in C57BL/6
Park S, Shin WS, Ho J.
Radix panax ginseng (Panax
ginseng C.A. Meyer, Araliaceae, RPG) has been documented to possess
hair growth activity and widely used to treat alopecia, while no
report has been issued to date on the effect of Fructus panax ginseng
(FPG) on hair regeneration.
MATERIALS AND METHODS:
investigate the effects of FPG extract on the proliferation of human
hair dermal papilla cells (DPCs) and on the promotion of hair
regeneration in C57BL6 mice, cell proliferation was evaluated in
cultured DPC by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium
bromide (MTT) and measured the expressions of Bcl-2 and Bax by
immunoblot assay. We also compared the effects of topical FPG extract
(1 and 10mg/ml, 100ìl/d) with the effects of minoxidil as a
positive control (5%, 100ìl/d) or vehicle control (30%
ethanol) on the depilation-induced hair cycling in 7 week-old-C57BL/6
FPG extract significantly increased the
proliferation of DPCs in dose and time dependent manners . FPG
extract also enhanced Bcl-2
expression and decreased Bax expression compared with control.
Moreover, significant elongations of anagen phase during hair cycle
after application of FPG were evaluated by photographical and
improves the cell proliferation of human DPCs through anti apoptotic
activation. Topical administration of FPG extract might have hair
regeneration activity for the treatment of hair loss.
edited for hair loss blog use
Dr Proctor's Hair loss treatment
and Follistatin Containing Treatment for Hair Loss
Dr Proctor sez: Some of our agents may work thru some of the
these same pathways.
J Drugs Dermatol. 2011
Regrowth Following a Wnt- and Follistatin Containing Treatment:
Safety and Efficacy in a First-in-Man Phase 1
Zimber MP, et al
has shown the importance of follistatin, Wnt 7a,
and wound healing growth factors on the stimulation of bulge cells
and inter-follicular stem cells to induce hair growth. We have
studied the effects of a bioengineered, non-recombinant, human
cell-derived formulation, termed Hair Stimulating Complex (HSC),
containing these factors to assess its hair growth activity in male
pattern baldness. HSC showed in vitro Wnt activity and contained
follistatin, KGF, and VEGF. The clinical study was a double-blind,
placebo-controlled, randomized single site trial and was designed to
evaluate safety of the HSC product and assess efficacy in stimulating
hair growth. All 26
subjects tolerated the single, intradermal injection of HSC
procedures well, and no signs of an adverse reaction were reported.
Histopathological evaluation of the treatment site biopsies taken at
weeks post-treatment revealed no abnormal morphology, hamartomas, or
other pathological responses. Trichoscan image analysis of
HSC-treated sites at 12
weeks showed significant improvements in hair growth over the
placebo. At the initial 12-week
evaluation period, HSC-treated sites demonstrated an increase in hair
shaft thickness (6.3%±2.5%
thickness density (12.8%±4.5%
and terminal hair density (20.6±4.9%
At one year, a statistically significant increase in total hair count
continued to be seen. These results demonstrate that a single
intradermal administration of HSC improved hair growth in subjects
with androgenetic alopecia and is a clinical substantiation of
previous preclinical research with Wnts, follistatin, and other
growth factors associated with wound healing and regeneration. J
Drugs Dermatol. 2011;10(11):1308-1312.
edited for hair loss blog use.
associated with eye changes ?
Dr Proctor sez: To my knowledge, this potentially-serious eye
problem does not happen when minoxidil is taken orally. So most
likely, it is just coincidental. But I will keep my eye on
Cutan Ocul Toxicol. 2011
chorioretinopathy associated with topical use of minoxidil 2%
for treatment of baldness.
Scarinci F, et
Purpose: Minoxidil is one of the drugs
approved for the treatment of androgenetic alopecia or male pattern
hair loss. This article presents a case of central serous
chorioretinopathy after application of topical minoxidil solution.
Methods: We examined a 37-year-old
man who complained of a positive relative scotoma, metamorphopsia and
impaired dark adaptation involving the right eye. The patient
reported an 8
month history of daily topical use but denied previous treatment with
other drugs. Dilated fundus examination of right eye revealed central
swelling located over the macula. Optical coherence tomography showed
the presence of subretinal fluid. Fluorescein angiography disclosed
one focal hyperfluorescent spot in the foveal area with minimal
pigmentary changes limitated to that area. The patient was diagnosed
with central serous chorioretinopathy (CSC) potentially related to an
month topical minoxidil solution administration. One month after the
drug was discontinued, normal findings were found upon reexamination.
The patient reported no previous episode of CSC. Conclusion: Major
systemic side effects from topical solution of minoxidil are rare. To
our knowledge, this is the first reported case of a central serous
chorioretinopathy associated with long-term use of this drug.
loss hair loss treatment and hair regrowth
Dr Proctor's Hair
loss treatment website.
Decrease, Erectile Dysfunction, and Depression with Propecia
Traish, A. M., Hassani, J., Guay, A. T., Zitzmann, M. and Hansen,
M. L. (2011),
Adverse Side Effects of 5á-Reductase
Inhibitors Therapy: Persistent Diminished Libido and Erectile
Dysfunction and Depression in a Subset of Patients. The Journal of
Sexual Medicine, 8:
finasteride and dutasteride, have been approved for treatment of
lower urinary tract symptoms, due to benign prostatic hyperplasia,
with marked clinical efficacy. Finasteride is also approved for
treatment of hair loss (androgenetic alopecia). Although the adverse
side effects of these agents are thought to be minimal, the magnitude
of adverse effects on sexual function, gynecomastia, depression, and
quality of life remains ill-defined.
Aim. The goal of this
review is to discuss 5á-RIs
therapy, the potential persistent side effects, and the possible
mechanisms responsible for these undesirable effects.
We examined data reported in various clinical studies from the
available literature concerning the side effects of finasteride and
Main Outcome Measures. Data reported in the
literature were reviewed and discussed.
adverse effects on sexual function such as erectile dysfunction and
diminished libido are reported by a subset of men, raising the
possibility of a causal relationship.
Conclusions. We suggest
discussion with patients on the potential sexual side effects of
before commencing therapy. Alternative therapies may be considered in
the discussion, especially when treating androgenetic alopecia.
Traish AM, Hassani J, Guay AT, Zitzmann M, and Hansen M. Adverse side
effects of 5á-reductase
inhibitors therapy: Persistent diminished libido and erectile
dysfunction and depression in a subset of patients. J Sex Med
inhibitor treatment for hair loss-- potential side-effects
Dr Proctor sez: This is an interesting review on the potential
side-effects of (e.g.) finasteride and dutasteride used for hair loss
inhibitor therapy: Should physicians be concerned with persistent
diminished libido, erectile dysfunction and depression in a subset of
inhibitors have been approved for treatment of androgenetic alopecia
and benign prostatic hypertrophy (BPH) with marked clinical efficacy.
The magnitude of adverse effects of these agents on sexual function
and quality of life varies considerably among patients and remains in
question. However, to what extent 5á-redctase
inhibitor therapy adversely affects sexual function, depression and
quality of life is yet to be addressed? More importantly, should
physicians be concerned regarding these adverse effects, especially
when treating benign conditions of androgenetic alopecia and
Abdulmaged M. Traish, John Hassani, Andre T. Guay,
Michael Zitzmann, Michael L. Hansen
journal of men's health
Proctor's Hair loss treatment website.
of Finasteride ( Propecia ) in the treatment of male pattern hair
Dr Proctor sez: The following paper is a very good general review
of the literature on hair loss treatment with finasteride ( Propecia
Dermatology: Review Efficacy and Safety of Finasteride Therapy for
Androgenetic Alopecia A Systematic Review
Manuel Mella, MD; María Clara Perret, MD; Matías
Manzotti, MD; Hugo Norberto Catalano, MD, PhD; Gordon Guyatt, MD, PhD
Arch Dermatol. 2010;146(10):1141-1150.
Androgenetic alopecia is the most common form of alopecia in men.
Objective To determine the efficacy and safety of finasteride
therapy for patients with androgenetic alopecia.
Sources: MEDLINE, EMBASE, CINAHL, Cochrane Registers, and LILACS were
searched for randomized controlled trials reported in any language
that evaluated the efficacy and safety of finasteride therapy in
comparison to treatment with placebo in adults with androgenetic
Study Selection and Data Extraction: Two reviewers
independently evaluated eligibility and collected the data, including
assessment of methodological quality (Jadad score). Outcome measures
included patient self-assessment, hair count, investigator clinical
assessment, global photographic assessment, and adverse effects at
short term (12
months) and long term (24
months). Heterogeneity was explored by testing a priori hypotheses.
Data Synthesis: Twelve studies fulfilled the eligibility
male patients), 10
of which demonstrated a Jadad score of 3
or more. The proportion of patients reporting an improvement in scalp
hair was greater with finasteride therapy than with placebo treatment
in the short term (relative risk [RR], 1.81
confidence interval (CI), 1.42-2.32];
and in the long term (RR, 1.71
both results were considered to have moderate-quality evidence. The
number needed to treat for 1
patient to perceive himself as improved was 5.6
in the short term and 3.4
in the long term. Moderate-quality evidence suggested that
finasteride therapy increased the mean hair count from baseline in
comparison to placebo treatment, expressed as a percentage of the
initial count in each individual, at short term (mean difference
and at long term (MD, 24.3%
Also, the proportion of patients reported as improved by investigator
assessment was greater in the short term (RR, 1.80
number needed to treat, 3.7
(moderate-quality evidence). Moderate-quality evidence suggested an
increase in erectile dysfunction (RR, 2.22
number needed to harm, 82.1
and a possible increase in the risk of any sexual disturbances (RR,
The risk of discontinuing treatment because of sexual adverse effects
was similar to that of placebo (RR, 0.88
evidence suggests that daily use of oral finasteride increases hair
count and improves patient and investigator assessment of hair
appearance, while increasing the risk of sexual dysfunction.
deficiency and diffuse nonscarring scalp alopecia in women
Dr Proctor notes: The relationship between iron deficiency and
hair loss in women is still not very well worked out.
Acad Dermatol. 2010
deficiency and diffuse nonscarring scalp alopecia in women: More
pieces to the puzzle.
St Pierre SA, et al
relationship between nonscarring scalp alopecia ( hair loss ) in
women and iron deficiency continues to be a subject of debate. We
review the literature regarding the relationship between iron
deficiency and nonscarring scalp alopecia and describe iron-dependent
genes in the hair follicle bulge region that may be affected by iron
deficiency. We conclude with a description of our approach to the
diagnosis and treatment of nonscarring alopecia in women with low
iron stores. Limitations include published studies with small numbers
of patients, different study designs, and absence of randomized,
controlled treatment protocols. Additional research regarding the
potential role of iron during the normal hair cycle is needed, as is
a well-designed clinical trial evaluating the effect of iron
supplementation in iron-deficient women with nonscarring
Copyright © 2009
American Academy of Dermatology, Inc. Published by Mosby, Inc. All
Edited for hair loss blog
in treatment of hair loss in alopecia areata
Could azathioprine be considered as a therapeutic alternative in
the treatment of alopecia areata? A pilot study
Journal of Dermatology, 10/05/2010
S et al. – No significant statistical difference was observed
with respect to gender before and after azathioprine treatment.
Treatment with azathioprine as a systemic monotherapy clinically
produces relevant improvement in moderate–to–severe hair
loss due to alopecia areata. Generally azathioprine is a low–cost
and well–tolerated drug and with controlled studies on larger
number of patients, long–term efficacy and safety of this
treatment should be investigated.
Edited for hair loss
Dr Proctor's Hair loss treatment
Posted in Welcome
Follicle Regrowth and Regeneration
Dr Proctor: Being able to regrow and multiply hair follicles is
an important step in the treatment of hair loss.
follicle neogenesis induced by cultured human scalp dermal papilla
Qiao J,-et al
AIM: To develop a method by which
human hair follicle dermal papilla cells can be expanded in vitro
while preserving their hair-regrowth potential for use in follicular
cell implantation, a cellular therapy for the treatment of hair loss.
RESULTS: ....( Hair follicle ) cultures from
numerous donors reproducibly resulted in an expansion that averaged
approximately five population doublings per passage. Furthermore, the
cells consistently induced hair formation in an in vivo graft assay.
Grafted DP cells appeared in DP structures of newly formed hairs, as
well as in the dermal sheath and in the dermis surrounding follicles.
Induced hair follicles persisted and regrew after being plucked 11
months after grafting. A process for the propagation of human DP
cells has been developed that provides significant expansion of cells
and maintenance of their hair-regrowth inductive capability,
overcoming a major technical obstacle in the development of
follicular cell implantation as a treatment for hair loss.
for hair loss treatment blog use.
J Proteome Res. 2010
is a Potential Major Autoantigen in Human Alopecia Areata.
MC, et al
Several lines of evidence support an
autoimmune basis for hair loss due to alopecia areata (AA), a common
putative autoimmune hair loss disorder. However, definitive support
is lacking largely because the identity of hair follicle (HF)
autoantigen(s) involved in its pathogenesis remains unknown. Here, we
isolated AA-reactive HF-specific antigens from normal human scalp
anagen HF extracts by immunoprecipitation using serum antibodies from
AA patients. Samples were analyzed by LC-MALDI-TOF/TOF mass
spectrometry, which indicated strong reactivity to the hair growth
phase-specific structural protein trichohyalin in all AA sera.
(K16) was also identified as another potential AA-relevant target HF
antigen. Double immunofluorescence studies using AA (and control
sera) together with a monoclonal antibody to trichohyalin revealed
that AA sera contained immunoreactivity that colocalized with
trichohyalin in the growth phase-specific inner root sheath of HF.
Furthermore, a partial colocalization of AA serum reactivity with
anti-K16 antibody was observed in the outer root sheath of the HF. In
summary, this study supports the involvement of an immune response to
anagen-specific HFs antigens in AA and specifically suggests that an
immune response to trichohyalin and K16 may have a role in the
pathogenesis of the enigmatic disorder.
and Hair loss
Am J Pathol. 2006
Title: Human Scalp Hair Follicles Are Both
a Target and a Source of Prolactin, which Serves as an Autocrine
and/or Paracrine Promoter of Apoptosis-Driven Hair Follicle
Kerstin Foitzik et al
Here, we provide the first evidence that human scalp HFs not only
express functional PRL-R but also serve as an important
extrapituitary site of PRL expression on the gene and protein level
(Figure 1, A–D, and Figure 4). Given that human skin has been
calculated to display ~5 million HFs, this calls attention to a very
substantial, newly identified source of potential PRL synthesis in
humans. This deserves further scrutiny and characterization, eg, in
healthy versus inflamed human skin, and definition of the quantity of
HF-derived PRL that is actually secreted systemically and thus exerts
genuine endocrine, rather than autocrine or paracrine
activities.Although our finding of intracutaneous transcription of
the PRL gene in human skin in situ is well in line with the previous
finding of PRL transcription in murine skin in vivo and in human
cultured dermal fibroblasts, keratinocytes, and sweat glands in
vitro,36,39 it conflicts with the report of Slominski and
colleagues40 who could not detect PRL mRNA in human skin by RT-PCR.
In our experiments, we detected PRL transcripts of the expected
length both in human full-thickness skin and in isolated human HFs,
using pituitary gland as positive control, and confirmed our data by
sequencing the PRL RT-PCR product. The negative PRL expression data
of Slominski and colleagues40 may be related to the fact that these
investigators studied sun-exposed truncal skin (containing primarily
vellus HFs, approximately half of which are in the telogen stage of
the hair cycle), whereas we analyzed scalp skin, which is unusually
rich in very large terminal HFs, 80 to 90% of which are in anagen VI
HF. In addition, we used different primer sequences and PCR
conditions than these investigators, who may well have identified an
alternatively spliced PRL mRNA variant that could not be detected
because of the exonal location of their primers. The sense primer
used by Slominski and colleagues40 was located in exon 3, and the
anti-sense primer contained both the end of exon 4 sequences and the
initial part of exon 5 sequences. In contrast, our sense primer is in
exon 2 and anti-sense primer is in exon 4.PRL mRNA as well as PRL and
PRL-R immunoreactivity can be detected within the same epithelial
human HF compartments (Figure 1, A–D, and Figure 4), and
culture of microdissected, denervated, and avascular HFs in the
presence of exogenous PRL exerts significant growth-modulatory
effects (Figure 1, E–H, and Figure 2, a and b). This supports
the hypothesis that PRL acts in an autocrine and/or paracrine manner
on locally expressed high-affinity receptors and functions as a
catagen-promoting signal in human HFs just as it does in mouse HFs.
The strictly epithelial immunoreactivity pattern of PRL and PRL-R
identified here for human scalp HFs corresponds well to the one
previously described in mice. However, in ovine HFs, PRL-R expression
has also been detected in the dermal papilla. Thus, expression of
PRL-R seems to be differentially regulated in seasonally dependent
HFs (ovine) compared to seasonally independent HFs (mouse,
human).Steroid hormones stimulate cognate receptors in the HF
epithelium and mesenchyme and change the secretion of potent hair
growth modulators such as TGF-â, which then act back on the
epithelium. In contrast, the polypeptide hormone PRL seems capable of
signaling more directly within the HF epithelium as an autocrine
and/or paracrine promoter of apoptosis-driven HF regression. However,
our currently available data do not allow us to exclude that the
observed HF effects of PRL were mediated at least in part also
indirectly. This could happen via the recognized effects of PRL on
peripheral androgen27 and estrogen metabolism, and/or via induction
of changes in the intrafollicular expression of PRL-sensitive growth
factors, cytokines, and enzymes with recognized hair
growth-modulatory functions,21 such as TGF-â1,55 vascular
endothelial growth factor,2 IGF-2, interferon-ã, and ornithine
decarboxylase.58Treatment of isolated human HFs in culture with PRL
results in apoptosis-driven HF regression (catagen), decreased
proliferation, and increased apoptosis of follicular keratinocytes
(Figure 3). These data correspond well to the rapid, premature
induction of apoptosis-driven catagen development in murine anagen
skin organ culture22 and to the reported catagen induction by PRL in
sheep in vivo. However, PRL has also been shown to exert
anti-apoptotic functions, eg, in cultured human breast cancer cell
lines in vitro, to act as a larval growth hormone and to be required
for limb regeneration in amphibians.61 Therefore, the
anti-proliferative and proapoptotic properties of PRL in HF
epithelium may not extend to all epithelial-mesenchymal interaction
systems and may be developmentally controlled.Although it remains to
be clarified how PRL exerts its activities on human HFs, we show that
PRL is a potent catagen-promoter of human HFs in vitro, with efficacy
comparable to that of TGF-â2, yet is lower than that of
interferon-ã. We also show that the catagen-promoting activity
of PRL is independent of the hypothalamus-pituitary-adrenal axis and
systemic hormone levels. It applies to HFs of a mammalian species
with mosaic and seasonally independent HF cycling (=human scalp HF).
PRL has long been recognized to play a role in hair growth control in
seasonally dependent coat changes, because both rising and falling
daily plasma PRL levels can induce moulting. The current human data
fit well with the previous reports that PRL induces premature catagen
in the, also seasonally independent, murine hair cycle22 and that
murine PRL-R-null mutants show longer and coarser hair as well as
hair cycle perturbations.23 The present data, therefore, underscore
the importance of PRL as a hair growth modulator for both seasonally
dependent and independent HF cycling across different mammalian
species.PRL has also been implicated in the pathogenesis of
androgenetic alopecia25 by modulation of androgens, and
hyperprolactemia is associated with an androgenetic alopecia-type
hair loss pattern, along with hirsutism (in females). Usually,
occipital scalp HFs are insensitive to hormones such as androgens. In
our experiments we used mostly occipital scalp HFs and additionally
frontal HFs. It is therefore particularly interesting that PRL was
able to induce catagen in these hormone-insensitive HFs. It is
important to mention that PRL may have distinct functions on distinct
areas of scalp and body HFs and that this will be an interesting
issue to investigate in the future. Recently, it has been shown that
neuroendocrine factors mediate stress-induced acne. HFs and the
sebaceous glands express functional receptors for stress-related
hormones, which are able to modulate androgen metabolism in the
sebaceous gland. These up-regulated androgens in the sebaceous gland
could also be involved in stress-induced hair loss. Therefore, it
will be interesting to investigate whether PRL is able to modulate
androgen receptor expression and/or androgen metabolism in the human
pilosebaceous unit. In summary, our study shows that human anagen
scalp HFs are very sensitive for inhibitory PRL-R-mediated signals.
This is clinically relevant, because it provides a reasonable
mechanism to explain the, as yet ill-understood, telogen effluvium
associated with hyperprolactinemia.25 It also points to novel
therapeutic strategies for the management of stress-related and
hormonal hair loss in men and women, by use of recently developed
for baldness blog
Keywords: hair loss treatment hair regrowth
balding minoxidil nano shampoo Dr Droctor tempol hair loss regrowth
propecia proxiphen (tm).
Dr Proctor's Hair loss treatment
Tags: hair, hair loss, hair loss treatment, hair
regrowth, loss, propecia, proxiphen, regrowth, treatment
and Hair loss
Interesting paper on the role of prolactin in the hair cycle. One
more thing that seems to drive the hair loss process. Dr Proctor
J Pathol. 2006
scalp hair follicles are both a target and a source of prolactin,
which serves as an autocrine and/or paracrine promoter of
apoptosis-driven hair follicle regression.
Foitzik K, et
The prototypic pituitary hormone prolactin
(PRL) exerts a wide variety of bioregulatory effects in mammals and
is also found in extrapituitary sites, including murine skin. Here,
we show by reverse transcriptase-polymerase chain reaction and
immunohistology that, contrary to a previous report, human skin and
normal human scalp hair follicles (HFs), in particular, express both
PRL and PRL receptors (PRL-R) at the mRNA and protein level. PRL and
PRL-R immunoreactivity can be detected in the epithelium of human
anagen VI HFs, while the HF mesenchyme is negative. During the HF
transformation from growth (anagen) to apoptosis-driven regression
(catagen), PRL and PRL-R immunoreactivity appear up-regulated.
Treatment of organ-cultured human scalp HFs with high-dose PRL (400
ng/ml) results in a significant inhibition of hair shaft elongation
and premature catagen development, along with reduced proliferation
and increased apoptosis of hair bulb keratinocytes (Ki-67/terminal
dUTP nick-end labeling immunohistomorphometry). This shows that PRL
receptors, expressed in HFs, are functional and that human skin and
human scalp HFs are both direct targets and sources of PRL. Our data
suggest that PRL acts as an autocrine hair regrowth modulator with
catagen-promoting functions and that the hair growth-inhibitory
effects of PRL demonstrated here may underlie the as yet
ill-understood hair loss in patients with
Modified for hair loss treatment blog