Steroidogenic isoenzymes in human hair and their potential role in androgenetic alopecia

Androgenetic alopecia: effects of oral finasteride on hormone profile, reproduction and sexual function

PURPOSE

Androgenetic Alopecia (AGA) is a common non-cicatricial alopecia. AGA treatment with finasteride was reported to have sexological side effects and its induced hormonal alterations could damage spermatogenesis. Thus, in patients affected by AGA undergoing oral therapy with Finasteride 1 mg/die, we aimed to evaluate the presence of modification in sperm parameters, hormone profile and sexual function.

METHODS

We retrospectively evaluated 55 male subjects aged 18-45 years with AGA who underwent systemic therapy with Finasteride 1 mg/die. Each subject underwent semen and blood hormone analysis, IIEF15 questionnaire administration at baseline (T0) at 6 (T6) and 12 (T12) months after the beginning of therapy and 1 year after treatment discontinuation (TD).

RESULTS

At T6 we detected a statistically significant worsening of total sperm number (232.4 ± 160.3 vs. 133.2 ± 82.0; p = 0.01 vs. T0) and abnormal forms (79.8 ± 6.0 vs. 82.7 ± 5.7; p < 0.05 vs. T0). No difference was found for all sperm parameters at T12 and T24, except for the percentage of abnormal forms (79.8 ± 6.0 vs. 82.6 ± 4.8; p < 0.05 T24 vs. T0). Testosterone levels were increased at T0 vs. T6 (22.1 ± 7.1 vs. 28.0 ± 8.0 ng/mL; p < 0.05). No significant differences of IIEF15 questionnaire were detected across the study.

CONCLUSIONS

Finasteride is associated with significant seminological and testosterone alterations, but no sexual dysfunctions were reported during treatment of these andrologically healthy subjects. Although, sperm parameters seem to return comparable to baseline after treatment discontinuation, it is advisable to perform a careful andrological evaluation before treatment.

Hair curvature: a natural dialectic and review

Although hair forms (straight, curly, wavy, etc.) are present in apparently infinite variations, each fibre can be reduced to a finite sequence of tandem segments of just three types: straight, bent/curly, or twisted. Hair forms can thus be regarded as resulting from genetic pathways that induce, reverse or modulate these basic curvature modes. However, physical interconversions between twists and curls demonstrate that strict one-to-one correspondences between them and their genetic causes do not exist. Current hair-curvature theories do not distinguish between bending and twisting mechanisms. We here introduce a multiple papillary centres (MPC) model which is particularly suitable to explain twisting. The model combines previously known features of hair cross-sectional morphology with partially/completely separated dermal papillae within single follicles, and requires such papillae to induce differential growth rates of hair cortical material in their immediate neighbourhoods. The MPC model can further help to explain other, poorly understood, aspects of hair growth and morphology. Separate bending and twisting mechanisms would be preferentially affected at the major or minor ellipsoidal sides of fibres, respectively, and together they exhaust the possibilities for influencing hair-form phenotypes. As such they suggest dialectic for hair-curvature development. We define a natural-dialectic (ND) which could take advantage of speculative aspects of dialectic, but would verify its input data and results by experimental methods. We use this as a top-down approach to first define routes by which hair bending or twisting may be brought about and then review evidence in support of such routes. In particular we consider the wingless (Wnt) and mammalian target of rapamycin (mTOR) pathways as paradigm pathways for molecular hair bending and twisting mechanisms, respectively. In addition to the Wnt canonical pathway, the Wnt/Ca(2+) and planar cell polarity (PCP) pathways, and others, can explain many alternatives and specific variations of hair bending phenotypes. Mechanisms for hair papilla budding or its division by bisection or fission can explain MPC formation. Epithelial-to-mesenchymal (EMT) and mesenchymal-to-epithelial (MET) transitions, acting in collaboration with epithelial-mesenchymal communications are also considered as mechanisms affecting hair growth and its bending and twisting. These may be treated as sub-mechanisms of an overall development from neural-crest stem cell (NCSC) lineages to differentiated hair follicle (HF) cell types, thus providing a unified framework for hair growth and development.

The clock gene brain and muscle Arnt-like protein-1 (BMAL1) is involved in hair growth

It is known that baldness caused by androgenetic alopecia is involved with androgen and the androgen receptor. Furthermore, it has been reported that testosterone secretion follows a circadian rhythm. Therefore, we hypothesized that a relationship exists between androgen-induced alopecia and biological rhythm. The mammalian circadian rhythm is controlled by several clock genes. Brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein-1 (BMAL1), one of the clock genes, is a transcription factor that plays central roles in the regulation of circadian rhythms. In this study, we investigated the influence of BMAL1 on hair follicle functions and hair growth. Mice deficient in BMAL1 expression exhibited a delay in hair regrowth after shaving. In hair follicles of mouse vibrissa, expression of Bmal1 and other clock genes was found to be rhythmic. Knockdown of BMAL1 in human follicle dermal papilla cells resulted in modulation of expression of several hair growth-related genes. Therefore, we concluded that expression of clock genes in hair follicles is linked to the circadian rhythm and that BMAL1 can regulate hair growth.

Expression and roles of steroidogenic acute regulatory (StAR) protein in 'non-classical', extra-adrenal and extra-gonadal cells and tissues

The activity of the steroidogenic acute regulatory (StAR) protein is indispensable and rate limiting for high output synthesis of steroid hormones in the adrenal cortex and the gonads, known as the 'classical' steroidogenic organs (StAR is not expressed in the human placenta). In addition, studies of recent years have shown that StAR is also expressed in many tissues that produce steroid hormones for local use, potentially conferring some functional advantage by acting via intracrine, autocrine or paracrine fashion. Others hypothesized that StAR might also function in non-steroidogenic roles in specific tissues. This review highlights the evidence for the presence of StAR in 17 extra-adrenal and extra-gonadal organs, cell types and malignancies. Provided is the physiological context and the rationale for searching for the presence of StAR in such cells. Since in many of the tissues the overall level of StAR is relatively low, we also reviewed the methods used for StAR detection. The gathered information suggests that a comprehensive understanding of StAR activity in 'non-classical' tissues will require the use of experimental approaches that are able to analyze StAR presence at single-cell resolution.

Clinical biochemistry of dihydrotestosterone

Dihydrotestosterone (DHT) is the most potent natural androgen in humans. There has been an increasing interest in this androgen and its role in the development of primary and secondary sexual characteristics as well as its potential roles in diseases ranging from prostate and breast cancer to Alzheimer's disease. Despite the range of pathologies shown to involve DHT there is little evidence for measurement of serum DHT in the management of these diseases. In this review we describe the physiology of DHT production and action, summarize current concepts in the role of DHT in the pathogenesis of various disorders of sexual development, compare current methods for the measurement of DHT and conclude on the clinical utility of DHT measurement. The clinical indications for the measurement of DHT in serum are: investigation of 5α reductase deficiency in infants with ambiguous genitalia and palpable gonads; men with delayed puberty and/or undescended testes; and to confirm the presence of active testicular tissue. Investigation is aided by the use of human chorionic gonadotrophin stimulation. Due to paucity of published data on this procedure, it is important to follow guidelines prescribed by the laboratory performing the analysis to ensure accurate interpretation.

The Efficacy and Safety of 17α-Estradiol (Ell-Cranell® alpha 0.025%) Solution on Female Pattern Hair Loss: Single Center, Open-Label, Non-Comparative, Phase IV Study

BACKGROUND

There are several commercially available agents to treat female pattern hair loss (FPHL), including minoxidil solution, anti-androgen agents and mineral supplements. However, these treatments are not always satisfactory. We report the results of a clinical trial of 17α-estradiol (Ell-Cranell® alpha 0.025%) solution to Korean female patients with FPHL.

OBJECTIVE

This study was designed to examine the efficacy and safety of Ell-Cranell® alpha 0.025% solution in Korean female patients with FPHL.

METHODS

A total of 53 women, 18 to 55 years old, applied topical Ell-Cranell® alpha 0.025% solution once daily for 8 months. Efficacy was evaluated by the change of hair counts and diameter, subjective assessment, and photographic assessment by investigators.

RESULTS

Hair counts and diameter from baseline to 4 and 8 months after treatment increased in treated patients and these changes were statistically significant (p<0.0001). 17α-estradiol (Ell-Cranell® alpha 0.025%) solution showed significant improvement by subjective self-assessment and by investigator photographic assessment. Ell-Cranell® alpha 0.025% solution was well tolerated over 8-months period.

CONCLUSION

This study showed that Ell-Cranell® alpha 0.025% solution is a safe and effective agent for Korean women with FPHL.

Gas chromatography/mass spectrometry based hair steroid profiling may reveal pathogenesis in hair follicles of the scalp

A method of steroid profiling, including androgens, progestins, corticoids and sterols, was developed to evaluate the concentrations of steroids as well as the activities of the enzymes responsible for steroidogenesis in hair by gas chromatography/mass spectrometry. The extraction efficiencies of steroids from the hair matrix were improved by ultrasonication for 1 h at 50 °C. The overall recoveries ranged from 71 to 132%, with a limit of quantification for all analytes ranging from 1 to 50 ng/g. The devised method was used to identify the metabolic changes for both male-pattern baldness (MPB) and the drug efficiency of dutasteride, which inhibits 5α-reductase. Increased dihydrotestosterone levels and the dihydrotestosterone/testosterone (DHT/T) ratio, which is responsible for the 5α-reductase activity, were observed in the MPB patients. A dutasteride treatment resulted in decreases in the DHT and 5α-androstanedione concentrations and DHT/T ratio in the hair samples. Hair steroid profiling reflects the sebaceous status in the scalp and may be useful for monitoring the metabolic responses to both the disease and drug actions.

Trace elements content and hormonal profiles in women with androgenetic alopecia

It is well-known that some trace element imbalances play a significant role in the pathomechanism of many forms of alopecia. Androgenetic alopecia, however, is a specific local sensitivity of hair follicle receptors to androgens. In a clinical and laboratory study, 153 women with androgenetic alopecia (AGA) and 32 control women were examined. In AGA patients telogen hair and vellus hair (miniaturization, D < 30 μm) significantly differed in frontal and parietal hair comparison with occipital area (20±0.9% vs. 12±0.5% and 33±0.9% vs. 12±0.6% respectively). In the AGA group levels of androstenedione and dihydrotestosterone were higher than in the control group. Hair elemental content, analyzed by ICP-MS, demonstrated a lowered Cu and Zn content in the frontal area in comparison to the occipital area. It is important to note, that the AGA patients with elevated levels of androstenedione and dihydrotestosterone presented an increased Cu content and decreased Mn, Se, Zn contents in the occipital area of scalp. The occipital level of Cu positively correlated with the concentration of free testosterone in the serum. A negative correlation between the Zn content in the occipital area and the dehydroepiandrosterone level in the blood was found. Unfortunately, a routine treatment course of AGA patients, including topical inhibitor of 5-alpha-reductase and minoxidil, had no effect on the Cu hair content in occipital and frontal areas. However, there were positive changes in the morphological structure and other trace element contents. These data led us to hypothesize a key role of Cu metabolism disturbances in the AGA onset, development of AGA, and potential pharmaceutical targets for the treatment of AGA.

Visually scoring hirsutism

BACKGROUND

Hirsutism is the presence of excess body or facial terminal (coarse) hair growth in females in a male-like pattern, affects 5-15% of women, and is an important sign of underlying androgen excess. Different methods are available for the assessment of hair growth in women.

METHODS

We conducted a literature search and analyzed the published studies that reported methods for the assessment of hair growth. We review the basic physiology of hair growth, the development of methods for visually quantifying hair growth, the comparison of these methods with objective measurements of hair growth, how hirsutism may be defined using a visual scoring method, the influence of race and ethnicity on hirsutism, and the impact of hirsutism in diagnosing androgen excess and polycystic ovary syndrome.

RESULTS

Objective methods for the assessment of hair growth including photographic evaluations and microscopic measurements are available but these techniques have limitations for clinical use, including a significant degree of complexity and a high cost. Alternatively, methods for visually scoring or quantifying the amount of terminal body and facial hair growth have been in use since the early 1920s; these methods are semi-quantitative at best and subject to significant inter-observer variability. The most common visual method of scoring the extent of body and facial terminal hair growth in use today is based on a modification of the method originally described by Ferriman and Gallwey in 1961 (i.e. the mFG method).

CONCLUSION

Overall, the mFG scoring method is a useful visual instrument for assessing excess terminal hair growth, and the presence of hirsutism, in women.

Nandrolone: a multi-faceted doping agent

Nandrolone or nortestosterone, an anabolic-androgenic steroid, has been prohibited by doping control regulations for more than 30 years. Although its main metabolism in the human body was already known at that time, and detection of its misuse by gas or liquid chromatographic separation with mass spectrometric detection is straightforward, many interesting aspects regarding this doping agent have appeared since.Over the years, nandrolone preparations have kept their position among the prohibited substances that are most frequently detected in WADA-accredited laboratories. Their forms of application range from injectable fatty acid esters to orally administered nandrolone prohormones. The long detection window for nandrolone ester preparations and the appearance of orally available nandrolone precursors have changed the pattern of misuse.At the same time, more refined analytical methods with lowered detection limits led to new insights into the pharmacology of nandrolone and revelation of its natural production in the body.Possible contamination of nutritional supplements with nandrolone precursors, interference of nandrolone metabolism by other drugs and rarely occurring critical changes during storage of urine samples have to be taken into consideration when interpreting an analytical finding.A set of strict identification criteria, including a threshold limit, is applied to judge correctly an analytical finding of nandrolone metabolites. The possible influence of interfering drugs, urine storage or natural production is taken into account by applying appropriate rules and regulations.

Cortisol determination in hair and faeces from domestic cats and dogs

The present study explored the feasibility of a hair cortisol assay in domestic cats (Felis silvestris catus) and dogs (Canis familiaris) as a valid and reliable alternative to existing non-invasive techniques for monitoring the hypothalamic-pituitary-adrenal (HPA) axis activity. To this aim, 56 new hair growth samples and 870 faecal samples from 27 domestic cats and 29 domestic dogs were collected and cortisol content was assessed. A significant positive association was observed in both species between the concentrations of cortisol determined in hair and faeces. This finding is discussed in the light of the existing knowledge of hair physiology and in the perspective of its application to studies on chronic stress.

Glucocorticoid and Sex Hormone Receptors: Clinical Implications and Therapeutic Relevance

In general, steroid hormones exert their effects through intracellular receptors, the glucocorticoid (GR), mineralocorticoid (MR), androgen (AR), estrogen (ER), and progesterone (PR) receptors. In this brief review, we will focus on glucocorticoid and sex hormone actions in the skin through their distinct receptors and discuss their clinical relevance.

Expression of sex-determining genes in the scalp of men with androgenetic alopecia

BACKGROUND

The regulation of the cutaneous steroidogenesis in patients with androgenetic alopecia remains largely unclear.

OBJECTIVE

The purpose of this study was to quantify the expression of the sex-determining genes in different scalp areas.

METHODS

Paired scalp specimens from frontal and occipital scalp areas of 10 patients were examined by real-time RT-PCR for mRNA expression and of 40 patients (mean age 34.9 years, range 22-58) by Western blotting for protein analysis.

RESULTS

The SOX-9 mRNA was most abundant in the skin, while SF-1 mRNA was sparsely detected. The protein levels of DAX-1, SRY and WT-1 were significantly higher in the bald scalp (p=0.003, 0.004 and 0.03, respectively). Only the SRY expression showed a positive correlation with the baldness severity in Norwood-Hamilton classification (p=0.024). There was no association between patient's age and the protein levels. Immunostaining of SOX-9 was detected in the outer root sheath keratinocytes of hair follicles but not in the dermal papillae.

CONCLUSION

Further study on a larger population, including normal subjects and female patients, is needed to confirm the pathogenic role of sex-determining genes in androgenetic alopecia.

Doping-Control Analysis of the 5α-Reductase Inhibitor Finasteride: Determination of Its Influence on Urinary Steroid Profiles and Detection of Its Major Urinary Metabolite

5alpha-Reductase inhibitors such as finasteride are prohibited in sports according to the World Anti-Doping Agency. This class of drugs is used therapeutically to treat benign prostatic hyperplasia, as well as male baldness, by decreasing 5alpha-reductase activity. Accordingly, metabolic pathways of endogenous as well as synthetic steroids are influenced, which complicates the evaluation of steroid profiles in sports drug testing. The possibility of manipulating steroid excretion profiles and, presumably, to mask steroid abuse was investigated in 5 administration studies with use of finasteride at different doses, with and without coadministration of 19-norandrostenedione. The evaluation of urinary steroid profiles demonstrated the intense effect of finasteride on numerous crucial analytical parameters, in particular the production of 5alpha-steroids such as androsterone and 5alpha-androstane-3alpha,17beta-diol, which was significantly reduced. In addition, the excretion of the main metabolite of norandrostenedione, norandrosterone, was significantly suppressed, by up to 84%, in elimination studies. For doping-control analysis the use of 5alpha-reductase inhibitors causes considerable problems because steroid profile parameters, which are commonly considered stable, are highly affected and complicate the detection of steroid abuse. In addition, the suppression of production and renal excretion of 5alpha-steroids such as 19-norandrosterone generated from anabolic agents such as 19-norandrostenedione may lead to false-negative doping-control results, because urine specimens are reported positive only when a threshold level of 2 ng/mL is exceeded. Finally, a method for the determination of the major urinary metabolite of finasteride (carboxy-finasteride) in routine doping-control screening with use of liquid chromatography-tandem mass spectrometry is described, allowing the detection of carboxy-finasteride for up to 94 hours in urine specimens collected after an oral administration of 5 mg of finasteride.

Patients with a large prostate show a higher prevalence of androgenetic alopecia

Androgenetic alopecia (AGA) and benign prostatic hyperplasia (BPH) are both androgen-dependent disorders, displaying in situ high levels of dihydrotestosterone with a good therapeutic response to finasteride. Embryological development of both the hair follicle and the prostate depends on mesenchymal-epithelial interaction, which is influenced by the expression of type 2 5alpha-reductase. The aim of this study was to elucidate the association between the size of the prostate gland and the prevalence and severity of AGA. A total of 46 patients age between 56 and 87 years were retrospectively recruited. They fulfilling the clinical diagnosis of BPH defined as (1) prostate volume > 30 cm3, measured by transrectal ultrasound, (2) maximal urine flow rate < 15 ml/s and mean urine flow rate < 10 ml/s, and (3) prostate serum albumin < 10 ng/ml. The control group comprised 34 patients aged between 49 and 81 years with urogenital infection, cystitis or urolithiasis. The expression and severity of AGA were evaluated by dermatologists using modified Norwood/Hamilton classification. Patients with a prostate volume > 30 cm3 had a higher prevalence of AGA than patients with a smaller prostate (< 30 cm3) (83.3% vs 61.3%; P < 0.05). The prostate size, however, did not correlate with the severity of AGA in either group or in the whole patient group. The prevalence of AGA was not significantly different in patients with or without BPH (85.7% vs 70.6%). The prostate was slightly larger among patients with AGA than among those without AGA (mean+/-SD 42.7+/-17.4 vs 35.4+/-14.9 cm3), but this was not statistically significant. There was no significant correlation between the age of onset of AGA and the development of BPH. Our results suggest that a larger prostate is associated with a higher prevalence of AGA. It remains to be seen if long-term use of finasteride in AGA patients will prophylactically lower the incidence of BPH.

Mild cutaneous manifestation in two young women with extraordinary hyperandrogenemia

Hyperandrogenism with hyperandrogenemia should be considered in those with severe acne of sudden onset or conspicuous male-pattern baldness with hairline recession, although the majority of female patients with acne or androgenetic alopecia possess no endocrine disorder. Herein we describe on the contrary 2 young women with primary amenorrhea displaying prominent hyperandrogenemia but subtle cutaneous manifestation. The first one presenting vertical alopecia had an elevated level of serum dehydroepiandrosterone sulfate (>800 microg/dl) and was suspected to be a case of late-onset, non-classical adrenal hyperplasia. The second case with mild acne had a soaring serum level of total testosterone >9,000 ng/dl derived from an androgen-secreting adrenal adenoma overexpressing steroidogenic acute regulatory protein, P450 side-chain cleavage enzyme and aromatase. A careful patient history and a complete physical examination are mandatory in each individual female case with acne or alopecia. The possibility of adrenal tumor should be explored in patients with escalated circulating testosterone.

Normal head-hair length is correlated with its diameter

Shed head-hair fibres of young (16-20-year-old), nonalopecic women (n = 25), exhibiting both exogen clubs and anagen tips (EA) were studied. Such fibres are shown, for the first time, to comprise approximately 44% of shed hair and to form a uni-modal, positively skewed distribution with a mean length of 16.7 +/- 4.9 cm, which is also correlated with the length of the haircut. As individual fibres exit the skin in early anagen VI, their major-axis diameters increase rapidly to maxima at about 25% of their total potential length and subsequently decrease to their exogen clubs, at a rate of 1.31% per cm (n = 28). EA diameters are further correlated with their lengths. Maximal and proximal diameters increase by 1.40% per cm and 1.02% per cm increments in fibre lengths, respectively (P < 0.0001 each; n = 14), these changes being also different from each other (P < 0.001). Besides identifying and characterizing a new class of normal hair (EA) which will probably feature prominently in future hair research, this study reveals several other important aspects of hair growth: (i) the classically described concept of hair miniaturization in androgenetic alopecia (AGA) is excessively broad and should therefore be revised; (ii) female AGA need not necessarily require a mechanism for rapid miniaturization as recently proposed; and (iii) the putative large variability of normal hair diameters is significantly overestimated, which further opens the field of hair diameter evaluation as a biological indicator of disease and physiological function.

[Androgenetic alopecia]

Androgenetic alopecia is the most common form of hair loss in men and women. Although the clinical manifestations are different in men and women, the pathogenetic pathways leading to this type of hair loss are similar in both sexes. In short genetically predestined hair follicles show an increased sensitivity to androgens. In recent years, much new data concerning the pathophysiology, management and therapy of androgenetic alopecia has been gathered. This article gives a critical overview of these new findings and assesses their practical relevance.