Ultrasonic Hollow Microneedle Array (USHM) for Androgenetic Alopecia Treatment through Modulating the Expression of Hair-Growth-Associated Genes.

The application of finasteride through the skin to treat androgenetic alopecia shows promise, as it avoids side effects on the prostate and sexual function. However, the effectiveness has been limited due to the structure of the skin. In this study, we developed a drug delivery system called an ultrasound hollow microneedle array (USHM) to enhance the transdermal delivery of finasteride for the treatment of androgenetic alopecia. This technique successfully used ultrasonic cavitation effects in the skin to improve the delivery and therapeutic effects of finasteride. Hair regeneration experiments in mice showed that USHM accelerated hair regrowth by one to two treatment cycles compared to microneedle delivery and by three cycles compared to topical application. Analysis based on RNA sequencing showed that USHM-mediated finasteride delivery upregulated genes related to keratin filaments, intermediate filaments, and the intermediate filament cytoskeleton, enhancing hair regeneration. This study expands the potential of finasteride treatment for androgenetic alopecia and offers an effective strategy for transdermal drug delivery.