Fig. 2

Exosomal miR-199a-3p/145-5p acted as critical effectors in the promotion of PC12 cell differentiation inhibited by LPS by regulating downstream factors of NGF/TrkA. a Viability of PC12 cells treated with increasing doses of MSC-Exo (n = 3). Data are represented as mean ± SD. b The linear relationship between total RNA and exosomal proteins. The linear relationship between miR-199a-3p (c), miR-145-5p (d), and exosomal proteins. e Relative miR-199a/145-5p expression in control MSC-Exo and MSC-Exo with the inhibition of miR-199a/145-5p (Exo-K) (n = 6). Data are represented from min to max. f Cell viability of LPS-treated PC12 cells pre-stimulated with Exo and Exo-K. Data are represented as mean ± SD. g–j)Representative western blot images and quantitative analysis of NF-H, β-tubulin-III, and Neu-N expression in LPS- and NGF-stimulated PC12 cells pretreated with Exo and Exo-K (n = 3). Data are represented as mean ± SD. (k-l) Representative western blot images quantitative analysis of p-Akt and p-Erk expression in LPS- and NGF-stimulated PC12 cells pretreated with different doses of exosomes (n = 3). Data are represented as mean ± SD. (m-n) Representative images and quantitative analysis of PC12 cell neurite growth (red arrow) in LPS- and NGF-stimulated PC12 cells treated with Exo and Exo-K. Scale bar = 50 μm. Data are represented as mean ± SD. *, p < 0.05; **, p < 0.01. LPS lipopolysaccharide, MSC mesenchymal stem cell, MSC-Exo MSC-derived exosomes, Exo-K MSC-Exo with miRNA inhibition