How does Maitake water extracts inhibit the differentiation of the adipocyte ?

• Project/Area Number: 17500563
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Eating habits, studies on eating habits
• Research Institution: Mukogawa Women's University
• Principal Investigator: OHTSURU Masaru Mukogawa Women's University, school of Human Environmental Sciences, Professor, 生活環境学部, 教授 (30110860)
• Co-Investigator(Kenkyū-buntansha): MINAMINO Katsuhiko Mukogawa Women's University, school of Human Environmental Sciences, Assistant, 生活環境学部, 助手 (80399138)
• Project Period (FY): 2005 – 2006
• Project Status: Completed (Fiscal Year 2006)
• Budget Amount: ¥3,200,000 (Direct Cost: ¥3,200,000); Fiscal Year 2006: ¥1,000,000 (Direct Cost: ¥1,000,000); Fiscal Year 2005: ¥2,200,000 (Direct Cost: ¥2,200,000)
• Keywords: Maitake / Animal cells / adipocyte / inhibition of differentiation / Functional food

Research Abstract

A bioactive substance inhibiting adipocyte differentiation was found in the water-soluble fraction of Maitake (Grifola frondosa). This substance is inhibited triglyceride (TG) accumulation both 3T3-L1, B2C1 and human adipocyte cells.
This substance was found to inhibit the differentiation of B_2C_1 preadipocytes, as determined by the decrease in the glycerol-3-phosphate dehydrogenase (GPDH) activity and leptin levels. Furthermore, this substances aren't related to MAP kinase (ERK1 and ERK2) cascade and β-catenin, that inhibited expression of Glut4, peroxisome proliferator activated receptor y (PPARy) and C/EBP α. Moreover, This substances reduced expression time of C/EBP β and C/EBP δ.
On the other hand, this substance substance was found to inhibit the differentiation of human preadipocytes, as determined by the decrease in the glycerol-3-phosphate dehydrogenase (GPDH) activity. Furthermore, this factor inhibited the expression of PPARy, C/EBP α, C/EBP β and C/EBP 6, one of the master regulators expressed early in adipocyte differentiation cascades. These results suggest that the application to the person might be able to be expected.
The bioactive substance was isolated by HPLC on ODS column, but available water phase. Now, we consider structure of purification sample by LC-MS, GC-MS, NMR.