[Effect of icariin on osteoblastic differentiation gene expression of human periodontal ligament cells].

OBJECTIVE: To observe the effect of icariin on human periodontal ligament cells (hPDLCs) differentiation to osteoblast gene expression. METHODS: The fifth generation of the cultured hPDLCs was added with the concentration of 0.01 mg/L icariin, and the added osteogenic medium used as blank control group, alizarin red staining of icariin on human periodontal ligament cells was observed for 21 days; the 2, 4, and 6 days of Q-PCR quantitative analysis of icariin on human periodontal ligament cells were made for osteogenesis gene alkaline phosphatase (ALP), type I collagen and osteocalcin (OC) gene expression. RESULTS: For the 21 days, alizarin red staining icariin group formed more mineralized nodules; on the 2nd, 4th, and 6th days, the group of icariin promoted the expression of ALP and OC mRNA, reached the peak value on day 6, compared with the control group with significant difference (20.15±6.67 vs. 7.90±0.71, 4.13±0.56 vs. 3.55±0.08, P<0.01). The second day, the highest expression of type I collagen appeared, then decreased gradually after, statistically compared with the control group (P<0.05). CONCLUSION: Icariin can promote the human periodontal ligament cells differentiation to osteoblast, and promote the osteogenesis gene expression.

Stem cells from human exfoliated deciduous teeth correct the immune imbalance of allergic rhinitis via Treg cells in vivo and in vitro.

BACKGROUND: Several studies have demonstrated that mesenchymal stem cells can ameliorate the inflammation of allergic rhinitis (AR) and correct the Th1/Th2 immune imbalance. METHODS: This study was performed to explore the immunomodulation properties of stem cells from human exfoliated deciduous teeth (SHEDs) in the treatment of AR in vivo and in vitro. BALB/c mice were sensitized to ovalbumin (OVA) by intraperitoneal injection, and then SHEDs or bone marrow mesenchymal stem cells (BMMSCs) were injected intravenously before challenge. We evaluated nasal symptoms, inflammatory infiltration of nasal mucosa, immunoglobulin secretion, cytokine production, and mRNA expression in the spleen. In addition, peripheral blood mononuclear cells (PBMCs) from AR patients were cultured with SHEDs or BMMSCs in the presence of phytohemagglutinin (PHA). PBMCs cultured alone with or without PHA served as controls. After 3 days of culture, we examined the effect of SHEDs on T lymphocyte proliferation, cytokine secretion, and the proportion of Foxp3+ Treg cells via flow cytometry. Finally, to determine the role of soluble factors (TGF-ß1, PGE2) in the immunomodulatory mechanism, a cytokine neutralization assay was performed. RESULTS: Nasal symptoms and inflammatory infiltration were significantly reduced after SHED administration. The OVA-specific IgE and IgG1 levels in serum were significantly decreased, and the increased IL-4, IL-5, IL-13, and IL-17A levels in the spleen after OVA challenge were markedly downregulated, while the level of IFN-γ was upregulated by SHED administration. The mRNA expression levels also changed correspondingly. SHEDs significantly inhibited the proliferation of T lymphocytes; increased the levels of IFN-γ, IL-10, PGE2, and TGF-ß1; decreased the levels of IL-4 and IL-17A; and induced the expansion of Treg cells in the coculture system. The neutralization of TGF-ß1 partly relieved the immunosuppression of SHEDs, but blocking PGE2 did not. In addition, SHEDs were superior to BMMSCs in inhibiting the Th2 immune response in vivo and inducing the expansion of Treg cells in vitro. CONCLUSION: These results suggest that SHEDs could correct the CD4+ T cell immune imbalance via Treg cells and may be potential therapeutic agents for the treatment of allergic diseases, such as AR, in the future.

[Sonic hedgehog signaling enhanced the expression of histone demethylase, lysine-specific demethylase 8 in the head and neck squamous cell carcinoma cell line SCC-6].

OBJECTIVE: To determine whether the sonic hedgehog (Shh) signaling could regulate the expression of histone demethylases in the head and neck squamous cell carcinoma(SCC). METHODS: Human recombinant SHH-N protein or over-expression of the mutant 2 smoothened (M2-SMO) was applied to activate the Shh signaling in tongue squamous cell carcinoma cell line-SCC-6 in this study. Cyclopamine was used to block the Shh signaling in SCC-6. The real-time reverse transcription (RT)-PCR was used to detect the expression of histone demethylases at the mRNA level. RESULTS: The data showed that activation of the Shh signaling up-regulated the expression of histone demethylase, lysine-specific demethylase 8 (KDM-8) at the mRNA level by human recombinant SHH-N protein (1.841 ∼ 3.591 fold compare with untreated group; P < 0.01), over-expression of the M2-SMO also increased the expression of KDM-8 (1.358 ∼ 3.013 fold compared with empty vector group; P < 0.05), and after the Shh signaling was blocked by Cyclopamine, the expression of KDM-8 was down regulated (decreased 25.6% ∼ 66.6% compared with control cells, P < 0.05). CONCLUSIONS: Histone demethylase KDM-8 was downstream target gene of Shh signaling in head and neck squamous cell carcinoma cell line SCC-6, and its expression was positively regulated by the Shh signaling.