P164 Evaluation of pro-inflammatory cytokines, and cell growth inhibition in primary human cells culture from oral tissue treated with uretandimethacrylate (UDMA)

Abstract

Introduction Dental endodontic sealers are in intimate contact with tissues around the root apex for extended periods. New endodontic sealers have been developed in the past decade, but the biological responses to many new products are not well documented.After exposure to endodontic sealer based on Uretandimethacrylate (UDMA) in ex vivo expanded human dental pulp mesenchymal stem cells (DP-MSCs), human periodontal ligament mesenchymal stem cells (PDL-MSCs), human osteoblasts (HOSTs) and human gingival fibroblasts (HGF) were evaluated: morphological features and cells growth. Moreover, the secretion of pro-inflammatory cytokines as: interleukin-1 Beta (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), interleukin-12 (IL-12), tumor necrosis factor-Alpha (TNF-α) at 24 h of UDMA treatment was assessed. Methods DP-MSCs and PDL-MSCs were derived from the dental pulps and the periodontal ligament of 10 young donors. HGF was derived from gingival biopsy. HOSTs were derived from maxilla periosteum. After in vitro isolation, DP-MSCs, PDL-MSCs, HGF and HOSTs were treated with UDMA, and after 24, 48 and 72 h and 1 week of incubation, their morphological features were analysed by light and confocal microscopy. To evaluate the, cell growth an MTT assay was performed. The release of IL-1β, IL-6, IL-8, IL-10, IL-12, TNF-alpha was analysed by ELISA test. Differences in the cell growth and in the interleukin secretion were analysed for statistical significance with two-way anova tests and the Holm-Sidak method for multiple comparisons. Results The UDMA treatment induces a cells growth inhibition in all the different analysed cells line. At microscopic level the cells don’t showed morphological changes, in fact the fibroblastoid features with cytoplasmic processes was observable. An up-regulation of IL-6 IL-8 and TNF-α was present in DP-MSCs, PDL-MSCs, HOSTs and HGF at 24 h of treatment. On the contrary IL-12 was over-expressed only in the PDL-MSCs, while the IL-1β in the DP-MSCs. Conclusion This work shows endodontic sealers may alter the cell growth, and in treated samples to induce an up-regulation of soluble mediators of inflammation such as IL-6, IL-8 and TNF-α cytokines. The direct application of UDMA potentially induces an inflammation process that could be the starting point for toxic response and cell damage in DP-MSCs, PDL-MSCs, HGF and HOSTs.