Fig. 4.

HA–iMSC–EVs restored hair regrowth and hair follicle cycles in testosterone-induced AGA mice. A Experimental design. B Images of the change of hair growth. Vehicle control denotes mice received topical application of 50% ethanol followed by repeated SC injection of D-PBS. AGA mice received topical application of testosterone followed by repeated SC injection of designated articles. C, D Quantification of hair regrowth area. ImageJ software was used and the relative area of hair growth against those at D1 was obtained. *p < 0.05, **p < 0.01, ****p < 0.0001 versus testosterone-only group E Body weight change. AGA, androgenetic alopecia; D-PBS, Dulbecco’s Phosphate Buffered Saline; EV, extracellular vesicle; HA, hyaluronic acid; iMSC, induced pluripotent stem cell-derived mesenchymal stem cell; SC, subcutaneous