Study on development of a novel remedy by antioxidative functions of green tea catechin for Sjogren's syndrome

Research Project

Project/Area Number	15K11067
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Pathobiological dentistry/Dental radiology
Research Institution	Tohoku University
Principal Investigator	Saito Keiichi 東北大学, 歯学研究科, 助教 (00178477)
Co-Investigator(Kenkyū-buntansha)	森士朗東北大学, 大学病院, 講師 (80230069)
Project Period (FY)	2015-04-01 – 2018-03-31
Project Status	Completed (Fiscal Year 2017)
Budget Amount *help	¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000) Fiscal Year 2017: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2016: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2015: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
Keywords	シェーグレン症候群 / 緑茶カテキン / aquaporin 5 / NF-κB / PKA / NF-kB / HMGB1 / RAGE / TLR-7 / TLR-9 / 唾液分泌 / エピガロカテキンガレート / NF kappa B
Outline of Final Research Achievements	We administered green tea catechin (epigallocatechin gallate; EGCG) to MRL-Fas (lpr) mice and examined suppressive effects of EGCG on autoimmune sialadenitis. Our results demonstrated that expression of aquaporin 5 (AQP5) at apical plasma membrane of submandibular gland acinic cells and that of protein kinase A (PKA) which promotes AQP5 production increased significantly compared with non-EGCG treated mice. Meanwhile, EGCG-treated mice displayed reduced expression of nuclear factor- κB (NF-κB) and its activator, c-Jun N-terminal kinase (JNK) and high-mobility group box-1 (HMGB1) as well as receptor for advanced glycation end products (RAGE) which are receptors of HMGB1 compared with non-EGCG treated mice. Taken together, our study show that EGCG serves as a salivary secretagogue in autoimmune sialadenitis.