Divergent progression pathways in male androgenetic alopecia and female pattern hair loss: Trichoscopic perspectives.

BACKGROUND: Despite similarities in progressive miniaturization of hair follicles and transition of terminal hairs to vellus hairs, insufficient trichoscopic comparisons between male androgenetic alopecia (MAGA) and female pattern hair loss (FPHL) hinder our ability to select effective treatments. AIM: Our study aimed to explore gender-specific trichoscopic characteristics of MAGA and FPHL, while formulating hypotheses regarding the progression of these conditions across clinical stages. METHODS: We classified 126 male MAGA subjects using Hamilton-Norwood Classification and 57 FPHL subjects using adopted Sinclair Scale. Subsequently, we analyzed nine trichoscopic factors divided into three categories: hair-diameter related, hair-number per follicular unit related, and hair density related factors. RESULTS: Of the nine quantitative trichoscopic factors, hair-diameter and hair-number per follicular unit showed strong correlations with clinical stages in both genders. Hair density, a common trichoscopic factor for hair loss evaluation, weakly correlated with clinical stages in FPHL, but not at all in MAGA. In addition, MAGA was characterized by a progressive reduction in hair-diameter, followed by a reduction in hair-number per follicular unit. FPHL, on the contrary, showed the opposite progression. CONCLUSIONS: Trichoscopic factors vary with disease severity in a gender-specific manner. Our research highlights that MAGA and FPHL involve two distinct streams: hair-diameter decreasing by hair follicle miniaturization (Stream 1), and hair-number per follicular unit decreasing by hair follicle tri-lineage niche dysfunction (Stream 2). MAGA typically starts from Stream 1 to Stream 2, while FPHL starts from Stream 2. These diverse progression pathways underscore the importance of personalized treatment approaches.

Trichoscopic evaluation of dental pulp stem cell conditioned media for androgenic alopecia.

BACKGROUND: Conditioned media (CM) derived from mesenchymal stem cells (MSC) is known to induce hair regrowth in androgenic alopecia. OBJECTIVES: The objectives of the study were to assess the efficacy and safety of one type of MSC-CM, the CM derived from dental pulp stem cells obtained from human exfoliated deciduous teeth (SHED-CM) and to compare the efficacy of SHED-CM with and without dihydrotestosterone synthesis inhibitor (DHT-inhibitor). METHODS: Eighty-eight male androgenic alopecia subjects with Hamilton-Norwood Classification (H-N C) I-VII were evaluated by trichoscopy to explore which trichoscopic factors statistically correlated with H-N C. After being screened, 33 subjects received six SHED-CM treatments at 1-month intervals. Clinical severity was assessed through global and trichoscopic images from baseline to 9th month. RESULTS: SHED-CM was effective for 75% of subjects regardless of disease severity, concomitant DHT-inhibitor use, and age. Adverse effects including pain and small hemorrhages were transient and mild. We also found that clinical hair status evaluated by absolute values of three quantitative trichoscopic factors (maximum hair diameter, vellus hair rate, and multi-hair follicular unit rate) showed a good correlation with H-N C stages, and what is more-a scoring system of these three factors can be a possible predictor of SHED-CM efficacy. CONCLUSIONS: We have shown that SHED-CM provides global and trichoscopic image improvement for androgenic alopecia, regardless of concomitant DHT-inhibitor use.