Fig. 6: Self-powered triboelectric-responsive MN system alleviated the senescence-associated degenerative process of IVDs.

A Schematic workflow for the needle puncture-induced degeneration of rat coccygeal IVDs treated with triboelectric-responsive MNs (n = 5 rats per group). B Gross pictures of coccygeal IVD model wearing with different equipments. C Representative X-ray images and EVs in vivo imaging showing the EV release kinetics in coccygeal IVDs at different time points. D Representative µCT images of coccygeal IVDs at different time points. E MR T2-weighted images and Pfirrmann MRI grades of rat IVDs with indicated treatments. F SO&FG staining of rat IVDs with the indicated treatments. G IF staining of PKH26-labeled EVs or mCherry in rat IVDs with the indicated treatments. The arrows indicated the PKH26⁺ or mCherry⁺ NP cells. H IHC staining of TRAM1 in rat IVDs with the indicated treatments. The arrows indicated TRAM1⁺ NP cells. I IF staining of p-STING in rat IVDs with the indicated treatments. J Pfirrmann MRI grades of rat IVDs with indicated treatments. K Histological score of rat IVDs with the indicated treatments. L Quantitative analysis of PKH26⁺ or mCherry⁺ NP cell proportions in rat IVDs with the indicated treatments. M Quantitative analysis of the TRAM1⁺ NP cell proportion in rat IVDs with the indicated treatments. N Quantitative analysis of the fluorescence intensity of p-STING in rat IVDs with the indicated treatments. Representative images of five independent biological replicates, and quantification of five independent biological experiments (J–N). A significant p value was determined by two-tailed ANOVA (J–N). Mean ± SD are shown for (J–N). n.s. not significant.