Fig. 4

Mitophagy is required for the protective effect of M2-exos against OGD/R-induced ferroptosis of HT-22 cells. (A, B) HT-22 cells were cultured under three conditions: normal (control), OGD/R (OGD), and OGD/R + 40 µg/mL M2-exos (M2-exos). After 24 h of culture, (A) The cells were stained with MitoTracker Red followed by immunostaining with LC3B-II antibody. Scale bar: 50 μm. (B) the expression levels of TIMM23, TOMM20 and LC3B-II were detected by western blot. (C–G) HT-22 cells were treated as follows: normal (control), OGD/R (OGD), OGD/R + M2-exos treatment (M2-exos), pretreated with vehicle (Vech), 3-methyladenine (3MA, 10 mM), or mitochondrial division inhibitor-1 (Mdi-1, 10 µM) followed by M2-exos treatment. After 24 h of treatment, (C) cell viability was determined by the CCK-8 assay. (D–F) the MDA, GSH and iron levels in each group were detected by specific kit, respectively. (G) The expression levels of SLC7A11, GPX4 and NCOA4 in each group were detected by western blot. **p < 0.01 compared with control group; ^#p < 0.05, ^##p < 0.01 compared with OGD group; ^&p < 0.05, ^&&p < 0.01 compared with M2-exos group.