Fig. 2

Chemogenetic stimulation induced PNS regeneration. A Chemogenetically stimulating DRG neurons in vitro 6 h after axotomy resulted in regeneration promotion. Data are expressed as the mean percentage of infected regenerating axons compared to the total of infected axons reaching the axonal compartment ± s.e.m (n = 7–8 axonal compartments). *p < 0.05 denotes significant differences in Student’s t-Test. B Representative images of hM3Dq/mCherry⁺ axons. Scale bar: 50 μm. C c-Fos nuclear staining is observed in hM3Dq infected DRG neurons (white arrows) 1 h after CNO injection, but not in mCherry⁺ DRG neurons after the same treatment. Scale bar: 25 µm. D Schematic timeline of the experiment. E The number of regenerating sensory axons (SCG-10⁺) in stimulated nerves (hM3Dq-CNO) is increased in all assessed distances compared to the non-stimulated (mCherry-CNO) reaching statistical significance in long distances. Data are expressed as mean ± s.e.m. at each distance from the injury site (n = 9 sciatic nerves). *p < 0.05 denotes significant differences in ANOVA followed by Bonferroni test. F SCG-10 immunostaining of mCherry or hM3Dq infected sciatic nerves 24 h after SNC. Dotted lines indicate the injury site. Scale bar: 200 μm