Fig. 2

AD-MSC-conditioned medium administration recovers sciatic nerve ultrastructure in diabetic mice. a Representative bright-field images of semithin sections of sciatic nerves obtained from 26-week-old non-diabetic and diabetic mice treated with vehicle, conditioned medium derived from non-preconditioned AD-MSCs, or conditioned medium derived from DFX-preconditioned AD-MSCs. Myelinated fibers were stained with toluidine blue. b Frequency distribution histogram of myelinated fibers. c Representative electron microscopy images of ultrathin sections of sciatic nerves. Asterisks indicate fibers with disrupted myelin sheath, and arrows indicate the separation of shrunken axon from myelin sheath. d G-ratio quantification for small caliber (< 6 μm diameter) and large caliber (> 6 μm diameter) myelinated fibers of sciatic nerve. Qualitative data are presented as mean ± S.E.M. (n = 6, one way ANOVA with Tukey post-test, *p < 0.05)