Department of Dental Biomedical Sciences

Department of Dental Biomedical Sciences

Our department learning and research activities focus on general to molecular understanding of the mechanism of diseases. The basic knowledge on the disease mechanism is very important to support new strategy for regenerative medical and dental therapies, including tissue engineering and drug delivery system. The following is the overview of the researches which have been being done in our department.

Identification of Sp6 target gene in dental epithelial cells

To develop regeneration therapy in the clinical treatment, we need to understand the developmental events at molecular levels. Although the profiles of gene expression are well-documented during tooth development and morphogenesis, the molecular mechanism of their regulations remains to be determined. In view of this, Sp6, a wherein Sp6 mRNA is expressed in a tissue-specific manner duringdevelopment, i.e., hair follicle, limb bud, and tooth germ. To investigate a possible role in tooth development, Sp6-overproducing clone is established and genome-wide screening of Sp6 target genes is performed. It has been identified that genes is performed. It has been identified that follistatin gene is one of the Sp6 target genes. Meanwhile, Sp6-mediated inhibition of the follistatin gene expression is suggested to be regulated at the transcriptional level. A role of Sp6 in amelogenesis is proposed through the down-regulation of the follistatin gene expression during tooth development and morphogenesis.

Inflammation induction by ligation of submandibular gland

In this dtudy, ligation of submandibular gland was done to induce inflammation. It is know from the study that stem cell antigen-I (Sca-I) expression increased by the ligation. The increase of Sca-I expression was due to the pro-inflammatory cytokine named IL-6 which induces STAT3 phosphorilation of Tyr705 through JAK-STAT and ERK I/2 pathways. On the next mechanism, P-STAT3 (Tyr705) bound to GAS element at Sca-I promoter region to induce Sca-I expression.

Hard tissue regenerative therapy by applying tissue engineering technology

Despite four decades of extensive efforts to provide bone substitutes, synthetic bone substituting materials are still largely inferior to auto- or allografts as the gold standard in orthopedic and dental surgery. The clinical success of the current generation of bone substituting methods is limited, since they lack the high functionality of bone tissue in terms of biological and mechanical properties. In our laboratory, matrices for bone repair to mimic nanostructure of bone are developed by applying tissue engineering technology which combines scaffold, growth factors, and cells. We have been trying to synthesize biomimetic structure with a nanodispersed mineral phase to provide structure for organizing dissociated cells into appropriate tissue construction by creating an environment that enables 3-D cell growth and neo-tissue formation (DOI: 10.1016/j.actabio.2009.09.005).