Development and Validation of A C57BL/6 Mouse Model of Androgenetic Alopecia Through Testosterone Propionate Induction

Abstract

Androgenetic alopecia (AGA) is the most prevalent form of progressive hair loss, primarily influenced by genetic and androgenic factors, particularly dihydrotestosterone. Existing therapeutic options show limited efficacy, emphasizing the need for reliable and representative animal models. This study established a testosterone propionate (TP)-induced C57BL/6 mouse model of AGA and evaluated the associated clinical, histopathological, and molecular alterations within the Wnt/β-catenin pathway. Twenty-one male C57BL/6 mice were randomized into seven groups (n = 3 per group): One control and six groups receiving subcutaneous testosterone propionate at 0.5, 1.0, or 1.5 mg/day for 7 or 14 days consecutive days. Hair regrowth, dermal thickness, follicle density, and β-catenin expression were analyzed using standardized morphometric and immunohistochemical analyses. Data with normal distribution were assessed using one-way ANOVA, while non-parametric data were evaluated with the Kruskal-Wallis test, followed by LSD or Dunn’s post hoc analysis. Statistical significance was set at p < 0.05. Low-dose, short-term treatment (0.5 mg/day for 7 days) produced only mild dermal thinning and partial follicular reduction, whereas higher doses and prolonged exposure induced progressive inhibition of hair regrowth. The regimen of 1.5 mg/day for 14 days resulted in complete growth arrest, pronounced dermal thinning, follicular depletion, and marked β-catenin suppression (p < 0.001, 0.028, and 0.017, respectively). Post hoc analysis confirmed significant reductions in dermal thickness (groups receiving 1.0 - 1.5 mg/day for 7 - 14 days), follicle density (1.5 mg/day for 7 days and 1.0 - 1.5 mg/day for 14 days), and β-catenin expression <1.5 mg/day for 7 and 14 days>. Despite the small sample size, this study demonstrates that subcutaneous TP administration at 1.5 mg/day for 14 days successfully induces androgenetic alopecia in C57BL/6. This model provides a robust, reproducible, and physiologically relevant platform for mechanistic exploration and preclinical testing of therapeutic agents tergeting Wnt/β-catenin signaling.

HIGHLIGHTS

• A reproducible testosterone propionate–induced androgenetic alopecia model was established in C57BL/6 mice.
• High-dose and prolonged androgen exposure caused dose- and duration-dependent hair growth inhibition.
• Dermal thinning, follicular miniaturization, and β-catenin suppression mirrored human AGA pathology.
• This model provides a robust platform for mechanistic studies and preclinical therapeutic evaluation.

GRAPHICAL ABSTRACT