Identify The Role Of AEG-1 In LPS-induced Dental Pulpitis

Aim To identify the role of astrocyte elevated gene-1(AEG-1)and the mechanism underlying the inflammatory response in dental pulp cells.Methodology To make sure whether AEG-1 paticipate in dental pulpitis,AEG-1 expression was detected at different stages of pulpitis in a rat model using immunohistochemistry;with primary dental pulp cells cultured from 15-25 years patients,RT-qPCR and Western blot were used to assess AEG-1 expression in human dental pulp cells stimulated by lipopolysaccharide(LPS).The LPS-induced expression of inflammatory cytokine genes was quantified by RT-qPCR in cells transfected with AEG-1 or negative control(NC)siRNA.Immunofluorescence and Western blot were utilized to evaluate the activation of NF-kB signaling in AEG-1-knockdown cells.AEG-1 expression was also investigated by Western blot in dental pulp cells pre-treated with inhibitors of NF-kB and PI-3K signaling before the addition of LPS.Data were statistically analysed by one-way ANOVA.Results The exposure of dental pulp tissue to LPS resulted in acute inflammation with necrosis and AEG-1 expression in the pulp tissue beneath the perforation.In LPS-stimulated dental pulp cells,AEG-1 mRNA and protein was significantly up-regulated(P<0.05)in a time-and dose-dependent manner.In AEG-1-knockdown cells,the synthesis of IL-1,IL-6,and TNF-a mRNA was suppressed significantly(P<0.05)upon LPS induction.AEG-1 knockdown also inhibited nuclear translocation of p65.Suppression of NF-kB and PI-3K abrogated the LPS-induced up-regulation of AEG-1.Conclusion AEG-1 participated in inflammatory cytokine synthesis via NF-kB signaling in dental pulp.Both NF-kB and PI-3K signaling are involved in LPS-induced AEG-1 expression in dental pulp cells.