An anti-hair loss treatment in the management of mild androgenetic alopecia: Results from a large, international observational study.

Androgenic alopecia (AGA) is a common and chronic condition. It may impact self-esteem, self-image and quality of life. Benefit, tolerability, cosmetic acceptance and patient satisfaction are key to ensure good treatment outcome. Hair loss improvement and hair quality with AC5 (2,4-Diamino-Pyrimidine-N-Oxyde, arginine, 6-O glucose linoleate (SP94), piroctone olamine and Vichy mineralizing water) once daily was assessed in 527 subjects with mild AGA in an open-label, observational, international real-life study. After 3 months, investigators evaluated the impact of AC5 on hair loss, product satisfaction and asked subjects about local tolerance; subjects assessed hair growth and quality and satisfaction. Data from 357 subjects were evaluable for the benefit analysis; 59.9% of subjects were female; the mean age was 33.6±8.7 years. Duration of hair loss was 1.62±2.24 years. 71.3% of women had a Ludwig score of 1 and 40.8% of men had a Hamilton Norwood score of 2. At the end of study, hair loss was reduced in 89.0% of subjects; it was slightly higher in women (92.5%) than in men (83.8%). Subject satisfaction on a scale from 0 (not satisfied at all) to 10 (completely satisfied) was 7.9±1.7. Tolerance was rated good to very good by 98.6% of all subjects. In conclusion, AC5 reduces mild AGA in both men and women with a pleasant texture. AC5 was well tolerated and highly appreciated.

Exploring some characteristics (density, anagen ratio, growth rate) of human body hairs. Variations with skin sites, gender and ethnics.

OBJECTIVE: To determine, in vivo, the density, growth rate and percentage of anagen phase follicles of body hairs present on five different skin sites (axilla, cheek, chin, leg, upper-lip) of women and men from four different ethnics (African, Caucasian, Chinese, North African). The same characteristics of terminal hairs from the nape of all subjects were recorded as references. METHODS: The photo-trichogram technique was used on all skin sites (of different sizes) at variable times (2 or 3 days) post shaving of small skin areas (a few cm2 ). Digital photographs were then analysed through a dedicated software that allows to record the density of body hairs (N cm-2 ), the % of growing hairs (Anagen phase) and their growth rates (in µm day-1 ). RESULTS: The densities of terminal hairs (on nape) found on all subjects were similar to those previously observed on much larger populations. The same ranking of a decreased density of body hairs in the five skin sites was observed in men, irrespective with ethnics. Body hairs seem homogeneously distributed among ethnics on armpit and leg with slight gender-related differences. In men, a significantly higher anagen phase percentage (> 85%) is found on terminal hairs, cheek and upper-lip region in Caucasians and North Africans, as compared to African and Chinese men. The technique used cannot precisely determine the very thin hairs present on the faces of all women. The anagen phase percentage appears higher in all women on leg and armpit. Hair body growth rates ranged from 180 to 485 µm day-1 and were found, on axilla, close to those of terminal hairs. CONCLUSION: The abundance of body hairs, in the studied skin sites, appears similar, irrespective with ethnic groups, whereas their functional characteristics (anagen ratio, growth rate) are more driven by individual/gender influences. RÉSUMÉ: Objectif Déterminer, in vivo, la densité, la vitesse de pousse et le pourcentage de follicules en phase anagènes des poils corporels présents sur 5 sites cutanés différents (l'aisselle, la joue, le menton, la jambe, la lèvre supérieure) de femmes et d'hommes issus de 4 groupes ethniques différents (Africain, Caucasien, Chinois, Nord-africain). Ces mêmes caractéristiques ont été enregistrées pour les cheveux (poils terminaux) en nuque de tous les sujets en tant que références. Méthodes la technique du photo-trichogramme a été utilisée sur tous les sites cutanés (de tailles différentes) après un temps variable (2 ou 3 jours) suivant le rasage de petites zones cutanées (quelques cm-2 ). Les photographies numériques ont été alors analysées par un logiciel spécifique qui permet d'enregistrer la densité de poils corporels (N.cm-2 ), le pourcentage de poils en phase de croissance (la phase Anagène) et leur vitesse de pousse (en µm/jour). Résultats la densité de cheveux (en nuque) trouvée sur tous les sujets était semblable à celle précédemment observée sur des populations beaucoup plus larges. On retrouve chez les hommes le même classement entre les 5 sites cutanés en termes de densité de poils corporels, indépendamment du groupe ethnique étudié. Les poils corporels semblent distribués de manière homogène parmi les membres d'un groupe ethnique sur l'aisselle et la jambe avec des légères différences liées au genre. Chez les hommes, les Caucasiens et les Nord-Africains présentent un pourcentage de poils terminaux en phase anagène significativement plus élevé (>85%) sur la joue et la région de la lèvre supérieure que les hommes Africains et Chinois. La technique utilisée ne permet pas précisément de déterminer la présence de poils très minces sur les visages des femmes. Le pourcentage de poils en phase anagène paraît plus élevé chez les femmes sur la jambe et l'aisselle. Les vitesses de pousse des poils corporels s'étendent de 180 à 485 µm/jours et se trouvent, sur les aisselles, proches de celles des cheveux. Conclusion la densité de poils corporels, dans les sites cutanés étudiés, présente une variabilité de sites indépendante du groupe ethnique considéré, tandis que leurs caractéristiques fonctionnelles (le ratio de poils en phase anagène, la vitesse de pousse) sont plus dirigées par des influences d'individu/genre.

Maintenance effect of a once-weekly regimen of a Selenium Disulfide-based shampoo in moderate-to-severe scalp seborrheic dermatitis after initial treatment with topical corticosteroid/salicylic acid.

INTRODUCTION: Seborrheic dermatitis (SD) is a chronic, relapsing, inflammatory disorder of the head and trunk. OBJECTIVES: To explore the potential of a 1% Selenium disulphide (SeS2)-based shampoo to prevent relapses of scalp SD (SSD) following corticosteroid/salicylic acid (TCS/SA) treatment. MATERIALS & METHODS: After a 2-week treatment with TCS/SA, adult patients with moderate-to-severe SSD received either the SeS2-based shampoo or its vehicle for eight weeks in a randomized, double-blinded fashion. Visits took place at baseline, weeks 2, 6 and 10. SSD severity was assessed based on erythema, flakes and pruritus; patients assessed the severity of pruritus. Global investigator and patient satisfaction were assessed at week 10. RESULTS: Forty-eight adults were included. After four and eight weeks of post TCS/SA maintenance regimen, 8.1% and 16.7% in the SeS2, and 41.7% and 54.2% in the vehicle group relapsed, respectively. First median time-to-relapse in the vehicle group was 56 days; this was not reached for SeS2. After two weeks of TCS/SA, the prevalence of patients with no pruritus was 29.2% in the SeS2 group, and 41.7% in the vehicle group; it increased to 76.2% with SeS2 and to 57.1% with the vehicle at the end of the study. The clinical benefit of treatment with TCS/SCA was maintained in the SeS2 group only. Investigators and patients were highly satisfied with the efficacy of SeS2. Tolerance to SeS2 was excellent, with no reported adverse events. CONCLUSION: The SeS2-based shampoo significantly reduces the time-to-relapse of moderate-to-severe SSD flares. Its tolerance was excellent, with no reported adverse events.

Selenium disulfide: a key ingredient to rebalance the scalp microbiome and sebum quality in the management of dandruff.

BACKGROUND: Dandruff is a chronic and relapsing scalp condition characterized by flaky scalp. Environmental and host factors (exposome) may alter the sebaceous gland activity, sebum composition, epidermal barrier function, and scalp microbiome balance, resulting in dandruff. Selenium disulfide (SeS2) improves the clinical signs of dandruff. OBJECTIVES: To investigate the mode of action of SeS2 shampoo during treatment and relapse phases. MATERIALS & METHODS: Two single-center studies assessed dandruff severity, subjective efficacy perception, microbial balance, microbiota diversity and sebum lipids. RESULTS: SeS2 significantly (p≤0.01) reduced scaling and led to a significant decrease of Malassezia and Staphylococcus spp. counts in both lesional and non-lesional areas, compared to the vehicle at D28 returning to baseline levels at D56. Cutibacterium spp. levels were not different between the SeS2 and the vehicle treatment groups but had significantly increased with SeS2 (p<0.001) in the lesional zone at D56. The ratio Malassezia spp./Cutibacterium spp. decreased significantly in lesional zones compared to baseline levels, at both D28 and D35 (p<0.001). The total squalene content significantly increased (p<0.05), whereas peroxided squalene had significantly decreased by almost 50% at D31. The ratio triglycerides/free fatty acids significantly (p<0.0001) increased, almost 5-fold, between D0 and D31. SeS2 shampoo was very well tolerated. CONCLUSION: SeS2 is beneficial in scalp dandruff, even after treatment interruption. It is well tolerated, rebalances the equilibrium between the main bacterial and fungal populations, and improves sebum quality.

Exploration of scalp surface lipids reveals squalene peroxide as a potential actor in dandruff condition.

Dandruff is a common but complex disorder with three major contributing factors: (1) individual predisposition, (2) scalp sebum and (3) Malassezia yeast colonization. To obtain further insights into the role of sebum in dandruff biogenesis, we analyzed scalp lipid species in a cohort of ten dandruff-free (control) and ten dandruff-afflicted volunteers by gas chromatography coupled to mass spectrometry. Lipid peroxidation levels and biochemical markers of oxidative stress were also assessed. Squalene, a major sebum component, was significantly more peroxidized in dandruff-affected scalps, resulting in significantly higher ratios of squalene monohydroperoxide (SQOOH)/squalene. This was observed when comparing dandruff-affected zones of dandruff subjects to both their non-affected zones and control subjects. In addition, other biomarkers such as malondialdehyde indicated that oxidative stress levels were raised on dandruff scalps. Surprisingly, differences regarding either free or bound fatty acids were fairly rare and minor. Certain novel findings, especially squalene peroxidation levels, were then confirmed in a validation cohort of 24 dandruff-affected subjects, by comparing dandruff-affected and non-dandruff zones from the same individuals. As SQOOH can induce both keratinocyte inflammatory responses and hyperproliferation in vitro, we hypothesized that increased SQOOH could be considered as a new etiological dandruff factor via its ability to impair scalp barrier function. Our results also indicated that Malassezia could be a major source of squalene peroxidation on the scalp.

Dandruff is associated with disequilibrium in the proportion of the major bacterial and fungal populations colonizing the scalp.

The bacterial and fungal communities associated with dandruff were investigated using culture-independent methodologies in the French subjects. The major bacterial and fungal species inhabiting the scalp subject's were identified by cloning and sequencing of the conserved ribosomal unit regions (16S for bacterial and 28S-ITS for fungal) and were further quantified by quantitative PCR. The two main bacterial species found on the scalp surface were Propionibacterium acnes and Staphylococcus epidermidis, while Malassezia restricta was the main fungal inhabitant. Dandruff was correlated with a higher incidence of M. restricta and S. epidermidis and a lower incidence of P. acnes compared to the control population (p<0.05). These results suggested for the first time using molecular methods, that dandruff is linked to the balance between bacteria and fungi of the host scalp surface.

Human skin model containing melanocytes: essential role of keratinocyte growth factor for constitutive pigmentation-functional response to α-melanocyte stimulating hormone and forskolin.

To study human skin pigmentation in a physiological in vitro model, we developed a pigmented reconstructed skin reproducing the three-dimensional architecture of the melanocyte environment and the interactions of melanocyte with its cellular partners, keratinocytes, and fibroblasts. Co-seeding melanocytes and keratinocytes onto a fibroblast-populated collagen matrix led to a correct integration of melanocytes within the epidermal basal layer, but melanocytes remained amelanotic even after supplementation with promelanogenic factors. Interestingly, normalization of keratinocyte differentiation using keratinocyte growth factor instead of epidermal growth factor finally allowed an active pigmentary system to develop, as shown by the expression of key melanogenic markers, the production, and transfer of melanosome-containing melanin into keratinocytes. Various degrees of constitutive pigmentation were reproduced using melanocytes from different skin phenotypes. Furthermore, induction of pigmentation was achieved by treatment with known propigmenting molecules, αMSH and forskolin, thus demonstrating the functionality of the pigmentary system. This pigmented full-thickness skin model therefore represents a highly relevant tool to study the role of cell-cell, cell-matrix, and mesenchymal-epithelial interactions in the control of skin pigmentation.