NOS3 and periodontitis: Lu et al. [41] found that PDLSC-Exos modulated alveolar bone regeneration in diabetic mice with periodontitis by delivering miR-31-5p, which targets eNOS to suppress osteoclast differentiation and decrease bone destruction in-vivo, with exosomes derived from normal glucose-cultured PDLSCs being more efficacious as compared to those from high-glucose-preconditioned PDLSCs.