Stem cells from human exfoliated deciduous teeth ameliorate concanavalin A-induced autoimmune hepatitis by protecting hepatocytes from apoptosis.

BACKGROUND: Autoimmune hepatitis is a serious autoimmune liver disease that threatens human health worldwide, which emphasizes the urgent need to identify novel treatments. Stem cells from human exfoliated deciduous teeth (SHED), which are easy to obtain in a non-invasive manner, show pronounced proliferative and immunomodulatory capacities. AIM: To investigate the protective effects of SHED on concanavalin A (ConA)-induced hepatitis in mice, and to elucidate the associated regulatory mechanisms. METHODS: We used a ConA-induced acute hepatitis mouse model and an in vitro co-culture system to study the protective effects of SHED on ConA-induced autoimmune hepatitis, as well as the associated underlying mechanisms. RESULTS: SHED infusion could prevent aberrant histopathological liver architecture caused by ConA-induced infiltration of CD3+, CD4+, tumor necrosis-alpha+, and interferon-gamma+ inflammatory cells. Alanine aminotransferase and aspartate aminotransferase were significantly elevated in hepatitis mice. SHED infusion could therefore block ConA-induced alanine aminotransferase and aspartate aminotransferase elevations. Mechanistically, ConA upregulated tumor necrosis-alpha and interferon-gamma expression, which was activated by the nuclear factor-kappa B pathway to induce hepatocyte apoptosis, resulting in acute liver injury. SHED administration protected hepatocytes from ConA-induced apoptosis. CONCLUSION: SHED alleviates ConA-induced acute liver injury via inhibition of hepatocyte apoptosis mediated by the nuclear factor-kappa B pathway. Our findings could provide a potential treatment strategy for hepatitis.

Local Administration of Stem Cells from Human Exfoliated Primary Teeth Attenuate Experimental Periodontitis in Mice.

OBJECTIVE: To evaluate the therapeutic effect of local injection of stem cells from human exfoliated primary teeth (SHED) on periodontitis in mice. METHODS: Fifteen female mice were randomly divided into three groups: normal control group, periodontitis group and SHED treatment group. A periodontitis model was established by ligating a 0.2 mm orthodontic ligation wire to the maxillary first molar. The SHED group was injected with SHED at 3 weeks post-ligation. All mice were sacrificed and their maxillae were dissected five weeks post-ligation. Clinical assessments, micro-computed tomography (micro-CT) scanning, and histologic examination were used to evaluate the outcome of tissue regeneration. RESULTS: Micro-CT analysis showed that SHED administration significantly increased periodontal regeneration and decreased the distance between the cemento-enamel junction and the alveolar bone crest. In addition, histopathological photomicrographs showed new regenerated bone, the number of TNF-α-positive, IFN-γ-positive and CD4+ cells decreased, and osteoclasts-positive decreased in the periodontal defect area in the SHED group compared with the periodontitis group. CONCLUSION: SHED administration suppresses the expression of inflammatory factors, inhibits the production of osteoclasts, and promotes the regeneration of periodontal tissues.