Human Umbilical Cord Mesenchymal Stem Cells and their Extracellular Vesicles Modulate Pro- and Anti-inflammatory Cytokines in Ligature-induced Periodontitis

Periodontitis is a chronic inflammatory condition that affects the tissues supporting the teeth, ultimately leading to tooth loss. Mesenchymal stem cells (MSCs) and their extracellular vesicles (EVs) play a crucial role in periodontitis by modulating the activities of gum cells and the immune system. To investigate the therapeutic potential of human umbilical cord mesenchymal stem cells (hUCSCs) and EVs in regulating the inflammatory response associated with periodontitis. hUCSCs were isolated, subjected to flow cytometry analysis of surface markers, and differentiated into adipocyte and osteocyte. hUCSC-EVs were isolated and characterized using flow cytometry and electron microscopy. A periodontitis animal model was established in 30 female C57Bl/6 mice. Experimental groups received hUCSCs or hUCSCs-EVs, or vehicles intravenously. Animals were monitored for 4 weeks, and the periodontal tissues were used to assess the effects of hUCSCs and hUCSCs-EVs on the expression of pro- (TNF-α, IFN-γ, and IL-17a) and anti-inflammatory cytokines (TGF-β, IL-10, and IL-4). The secretion of these cytokines by splenocytes was also evaluated using ELISA. The levels of IL-17a, IFN-γ, and TNFα significantly reduced, while TGF-β and IL-10 significantly increased in the periodontal tissues of the hUCSC and hUCSCEVs-treated mice. The expression of TNF-α, IFN-γ, and IL-17a significantly decreased, while the production of IL-10 and TGF-β significantly increased in splenocytes from the hUCSC and EVs-treated mice. hUCSCs and their EVs have the potential to attenuate the inflammatory response associated with periodontitis, possibly by downregulating pro-inflammatory cytokines and upregulating anti-inflammatory ones.