Exploration of novel hypothalamic mechanism on fatty food preference and its application to clinical science on obesity-diabetes syndrome

2014 Fiscal Year Final Research Report

• Project/Area Number: 24591338
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Metabolomics
• Research Institution: University of the Ryukyus
• Principal Investigator: MASUZAKI Hiroaki 琉球大学, 医学(系)研究科(研究院), 教授 (00291899)
• Co-Investigator(Kenkyū-buntansha): TAKAYAMA Chitoshi 琉球大学, 大学院医学研究科, 教授 (60197217) ; SHIMABUKURO Michio 徳島大学, 大学院医歯薬学研究部 心臓血管病態医学分野, 特任教授 (60271144)
• Research Collaborator: MATUSHITA Masayuki ; KOZUKA Chisayo
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 高脂肪食 / 視床下部 / 小胞体ストレス / 食行動 / 嗜好性 / 分子シャペロン / γ-オリザノール / 肥満症

Outline of Final Research Achievements

The present study demonstrated for the first time in mouse experiments that excess intake of fatty foods augments ER stress in hypothalamus, which in turn increases the preference for dietary fats, thereby making a self-adjusting circuit. Gamma-oryzanol is a unique bioactive substance exclusively and abundantly found in brown rice. We found that γ-oryzanol decreases ER stress in hypothalamus and attenuates the preference for dietary fat, thereby ameliorating high fat diet (HFD)-induced fuel dyshomeostasis. We also tested whether γ-oryzanol reduces ER stress and improves function and survival of pancreatic β-cells under high fat diet in mice. In pancreatic islets from HFD-fed diabetic mice, oral administration of γ-oryzanol improved glucose stimulated insulin secretion (GSIS) on following reduction of exaggerated ER stress and apoptosis. A line of novel findings may open a fresh avenue for natural food-based approach toward the prevention of obesity-diabetes syndrome.

Free Research Field

代謝学