Fig. 5

EVs derived from LPS-As-stimulated NSCs promoted axonal regeneration and remyelination, and the neurological recovery following SCI. A HE staining results showed that the injured areas were reduced by the injection of NSCs-EVs, As-NSCs-EVs or LPS-As-NSCs-EVs, compared to the rats that did not receive EVs injection. The LPS-As-NSC-EVs-injected rats had the smallest injured areas (n = 5, data are the mean ± S.D; ∗p < 0.05, ns p > 0.05). B–D The LPS-As-NSCs-EVs had the strongest effects in promoting the remyelination around the cavity at week 4 post injury (n = 5, data are the mean ± S.D; ∗p < 0.05, ns p > 0.05). E The western blot results revealed the alteration in Cnpase expression in the injured core at week 4 post-injury (n = 3, data are the mean ± S.D; ∗p < 0.05, full length original gels are included in Additional file 2: Figure S2). F, G Consistent with histological data, the LPS-As-NSCs-EVs-treated rats showed a better neurological recovery compared to the NSCs-EVs or As-NSCs-EVs-treated rats (n = 10, data are mean ± S. D). Significant differences in BBB scores were noted among all 3 groups at day 28 post-SCI. Similarly, differences in the angle of incline plane tests were found between the SCI and LPS-As-NSCs-EVs, As-NSCs-EVs, and LPS-As-NSCs-EVs groups at week 4 post-injury