Fig. 1
MSC-derived mitochondria injection can effectively promote nerve axon regeneration in a mouse sciatic nerve injury (SNI) model. (A) Schematic of the experiment. To construct the SNI model, the right thigh of each mouse was surgically exposed at the mid-thigh level to access the sciatic nerve. The sciatic nerve was then crushed with moderate force using a forceps for a duration of 10 s. For the mitochondrial treatment group, 2 µL of mitochondria derived from 106 MSCs were injected into the crush sites of the injured nerves. The injured sciatic nerves were removed 4 days later. After fixation and clearing, the nerves were whole-mount stained utilizing primary anti-Tuj1 antibodies and fluorescent secondary antibodies, imaging by a fluorescence microscope; (B) Representative immunofluorescence images of whole-mount sciatic nerves in the SNI group and SNI with mitochrondria injection therapy group (SNI + Mito) (left) and quantification of the average length of the top 5 axons with the longest regeneration distance in each group (right); (C) Fluorescence labeled mitochondrial tracer experiment. In the group injected with Mito-track labeled mitochodria, fluorescence were distributed along the axons (upper right), and were present in the DRGs associated with the injured sciatic nerves (upper left). In the Mito-track only control group, pure Mito-track dye without mitochondria were injected into the injured sciatic nerves, After 4 days, imaging of the sciatic nerve (lower right) and DRG (lower left) revealed minimal fluorescence distribution