Elucidation of mechanism on dentin hypersensitivity; cell response by hypertonic stress.

• Project/Area Number: 24592876
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Conservative dentistry
• Research Institution: Kagoshima University
• Principal Investigator: MASAYUKI Tokuda 鹿児島大学, 医歯(薬)学総合研究科, 准教授 (20253891)
• Co-Investigator(Kenkyū-buntansha): MORIMOTO Yoko 鹿児島大学, 医学部・歯学部附属病院, 助教 (30437967)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2014: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2013: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2012: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: 象牙質知覚過敏症 / 象牙芽細胞 / スクロース / 高浸透圧 / 細胞死 / 分裂促進因子活性化タンパク質キナーゼ / キシリトール / TRPV1 / AQP2 / 浸透圧 / 細胞内転写因子

Outline of Final Research Achievements

Osmotic stress is one cause of dental pain due to caries or dentin hypersensitivity. The mechanism of osmotic-induced dental pain is not completely understood. The purpose of this study was to examine the responses of odontoblasts under sucrose-induced hyperosmotic stress. Cell viability decreased over 700 mOsm for 3 h cell culture. The shapes of cells and nuclei became irregular and vacuolar under hyperosmotic stress. The expression of cleaved caspase-3 was increased after treatment with hyperosmotic stress. Flow cytometry analysis detected no annexin V-positive cells, indicating apoptosis. Three MAPKs phosphorylation were induced by hyperosmotic stress. Inhibitors of three MAPKs inhibited the hyperosmotic stress-induced decline in cell cultures at 500 and 700 mOsm. Hyperosmotic stress induces cell death of OLCs with sucrose through a MAPK pathway.

Research Products

• [Journal Article] Involvement of TRPV1 and AQP2 in hypertonic stress by xylitol in odontoblast cells. (2015)
  • Author(s): 35.Tokuda M*, Fujisawa M, Kawakami Y, Morimoto-Yamashita Y, Torii M
  • Journal Title: Connect Tissue Res. Volume: 56 Issue: 1 Pages: 44-49
  • DOI: 10.3109/03008207.2014.984804
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Hyperosmotic stress induces cell death in an odontoblast-lineage cell line (2012)
  • Author(s): M Fujisawa, M Tokuda, Y Morimoto-Yamashita, S Tatsuyama, S Arany, T Sugiyama, C Kitamura, Y Shibukawa, M Torii
  • Journal Title: Journal of Endodontics Volume: 38 Issue: 7 Pages: 931-935
  • DOI: 10.1016/j.joen.2012.03.023
  • Peer Reviewed
• [Presentation] 象牙芽細胞培養系におけるキシリトールによる高浸透圧刺激の影響 (2014)
  • Author(s): 徳田雅行，川井絢矢，作田哲也，小山徹，宮下桂子，藤澤真理，江本真規子，森元陽子，鳥居光男，松下健二
  • Organizer: 日本歯科保存学会秋季大会
  • Place of Presentation: 山形市（山形テルサ）
  • Year and Date: 2014-10-30 – 2014-10-31
• [Presentation] 象牙芽細胞培養系におけるキシリトールによる高浸透圧刺激の影響 (2013)
  • Author(s): 徳田雅行、藤澤真理、川上克子、江本真規子、鳥居光男
  • Organizer: 日本歯科保存学会
  • Place of Presentation: 秋田県総合生活文化会館