Supplementary Material for: Metformin Promotes the Hair-Inductive Activity of Three-Dimensional Aggregates of Epidermal and Dermal Cells Self-Assembled In Vitro

In 2021, a study was conducted to assess the effect of metformin, an anti-diabetic drug, on hair growth using a mouse hair follicle reconstitution model. The model was generated by in vitro self-assembled three-dimensional aggregates of epidermal and dermal cells (3D aggregates) from fifty C57BL/6 mouse pups. The 3D aggregates were treated with 10 mM metformin and grafted into recipient BALB/c nude mice. The study found that metformin directly stimulates the activity of alkaline phosphatase (ALP) of cultured 3D aggregates, upregulates both the protein and mRNA expression levels of molecular markers (HGF, CD133, ALP, β-catenin and SOX2), and improves the survival rate of reconstituted hair follicles. Additionally, metformin was found to increase the expression of CD133 in dermal cells, maintaining their trichogenic capacity that would normally be lost by serial subculture. The results suggested that metformin could promote hair follicle regeneration in vitro, indicating potential for further evaluation in the clinical treatment of male or female pattern hair loss.