REST and Huntington disease: For example, miR-124a-loaded exosomes that were secreted by MSCs or HEK293 cells significantly enhance adult neurogenesis post ischemia and TBI (Yang et al., 2017), repress REST expression in Huntington’s disease mouse model (Lee et al., 2017), promote the polarization of microglia into anti-inflammatory phenotype under neuroinflammatory conditions (Yang et al., 2019), and reduce in viability or clonogenicity of glioma cells (Lang et al., 2017).