Based on these results, here we investigated the possibility to impact on SMA progression by JNK inhibition: to this aim, we administered to SMNΔ7 mice (mouse model of intermediate SMA) a cell-penetrating JNK inhibitor (D-JNKI1) peptide, which selectively blocks the access of JNK to c-Jun and the other JNK-binding domain (JBD) dependent targets. This evidence concerns the gene MAPK8 and proximal spinal muscular atrophy.