Effect of human breast milk-derived exosomes on the migration and inflammatory response of lipopolysaccharide-exposed dental pulp stem cells

Abstract:Aim: The purpose of this study was to investigate the effects of human breast milk-derived exosomes (HM-Exos)on the viability,migration, and inflammatory responses oflipopolysaccharide (LPS)exposed human dental pulp stem cells (HDPSCs) in vitro condition.Methods: HM-Exoswere isolated, and dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy(TEM) were used to analyze their physiological properties (size and shape).To construct an in vitro inflammation model, HDPSCs were exposed to LPS.The MTT test and migration assay were used to investigate the effect of HM-Exos on cell proliferation and migration, and the quantitative polymerase chain reaction was used to assess the expression of inflammatory genes in HDPSCs.Results: DLS measurement revealed that HM-Exos were 116.83.6 nm in diameter. The SEM and TEM images revealed spherical shapes with diameters of 97.2±34.6 nm. According to the results of the cell viability assay, the maximal nontoxic concentration of HM-Exos (400 µg/ml) was chosen for the subsequent investigations. The migration assay results showed that HM-Exos improved the potential of HDPSCs to migrate under LPS-stimulated inflammatory processes. The RT-PCR results indicated that HM-Exos significantly reduced the expression of inflammatory cytokines such as TNF-α, IL-1β and IL-6 in آHDPSCs after LPS stimulation.Conclusions: HM-Exos reduced gene expression of inflammatory cytokinesin inflamed HDPSCs and may be a viable candidate for use as a pulp capping substance in vital pulp therapy.