Non-Invasive Assessment of Hair Regeneration in Androgenetic Alopecia Mice In Vivo Using Two-Photon and Second Harmonic Generation Imaging

September 2023 in “ Biomedical Optics Express ”

Gaiying He, Menghua Liu, Fenglong Wang, Shuangqing Sun, Yu Cao, Yanan Sun, Shuhua Ma, Yi Wang

androgenetic alopecia testosterone hair regeneration hair follicles miniaturized hair follicles two-photon excited fluorescence second harmonic generation imaging AGA TPEF SHG

Studysummary This study used non-invasive imaging techniques to assess hair follicle characteristics in AGA mice, revealing delayed hair shaft alternation and growth stages, as well as testosterone-induced follicle miniaturization, offering potential methods for evaluating AGA on human scalps in vivo.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

The study involved 66 male C57BL/6 mice and used non-invasive two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) imaging techniques to assess hair regeneration in androgenetic alopecia (AGA) mice. The TPEF imaging revealed that the growth period and the alternation of new and old hair shafts in AGA mice were delayed due to testosterone. SHG imaging found that testosterone reduced hair follicle area and miniaturized hair follicles. These techniques provide a non-invasive approach for assessing hair regeneration in AGA mice and could potentially be used for evaluating drug-induced hair regeneration in humans. However, the limited penetration depth of these imaging techniques remains a challenge.

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