TLDR Exosomes from dermal papilla cells can help grow hair and might treat hair loss.
In the 2018 study, researchers found that exosomes derived from dermal papilla cells (DPC-Exos) could promote hair follicle growth and development in mice. Injecting DPC-Exos into mice led to an accelerated transition into the anagen phase and a delayed transition into the catagen phase, resulting in longer hair shafts and larger hair bulb diameters. In vitro, DPC-Exos enhanced the proliferation and migration of outer root sheath cells and increased the expression of key signaling molecules like ß-catenin and Sonic hedgehog. These findings suggest that DPC-Exos could be a potential treatment for hair loss. The study used human scalp specimens from 15 individuals for cell isolation and included in vivo experiments on mice, although the exact number of mice used was not specified.
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