Neurotransmitter-Triggered Transfer of Exosomes Mediates Oligodendrocyte–Neuron Communication
Figure 8
Neuroprotective role of oligodendroglial exosomes.
(A) Boyden chamber co-culture of CN with or without pOL for 48 h under unstressed, oxidative stress, or nutrient deprivation (ND) conditions. Control CN cultured without pOL (black bars) were grown in oligodendrocyte-conditioned medium depleted from exosomes. Oxidative stress was induced after co-culture by challenging CN with 25 µM H2O2 for 1 h (n = 5). For nutrient deprivation, cells were cultured in medium lacking B27 supplement (n = 5). Neuronal viability was assayed by MTT assay. (B) Staining of the outer mitochondrial membrane with MitoCapture after nutrient deprivation and co-culture with and without pOL. Unstressed cells were grown in full medium without pOL. Scale bar, 100 µm. (C) Application of isolated exosomes and liposomes to neurons under conditions of cell stress. MTT assay of CN after single addition of isolated exosomes from pOL and HEK293T cells as well as liposomes 12–14 h prior to H2O2 stress (25 µM for 1 h) compared to unstressed or sham treated controls (n = 5). (D) MTT assay of CN subjected to nutrient deprivation and treated with exosome-containing (SN+exos) or exosome-deprived (SN w/o exos) oligodendrocyte culture supernatants for 12–14 h (n = 5). Error bars, SEM (n.s., not significant; * p<0.05; Wilcoxon-test).