Elucidation of interaction between regulation of food intake and brain reward system to understand over-eating

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K15347
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Metabolomics
• Research Institution: National Cardiovascular Center Research Institute
• Principal Investigator: Hosoda Kiminori 国立研究開発法人国立循環器病研究センター, 病院, 部長 (40271598)
• Co-Investigator(Renkei-kenkyūsha): MURAI Toshiya 京都大学, 医学研究科, 教授 (30335286) ; HIKIDA Takatoshi 京都大学, 医学研究科, 准教授 (70421378) ; MIYAZATO Mikiya 国立循環器病研究センター, 生化学部, 部長 (50291183) ; AOTANI Daisuke 京都大学, 医学研究科, 助教 (80600494) ; TANAKA Tomohiro 京都大学, 医学研究科, 准教授 (20402894) ; Kusakabe Toru 独立行政法人国立病院機構京都医療センター, 内分泌代謝高血圧研究部, 研究室長 (60452356)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 報酬系 / レプチン / 摂食 / 嗜好性 / 肥満

Outline of Final Research Achievements

Ob/ob mice Conditioned place preference (CPP) paradigm is a standard behavioral model to evaluate the rewarding value of substrates. While leptin is reported to decrease the CPP of lean mice for high fat diet (HFD), it is unknown how CPP toward HFD is affected by leptin replacement in the pathophysiological condition of ob/ob mice. In the present study, we performed the CPP test in order to clarify the effect of leptin on the preference of ob/ob mice for HFD. Ob/ob mice had a significantly higher HFD preference in CPP test when compared with wild-type (WT) mice and this preference was suppressed to the levels comparable to the WT mice by leptin replacement with or without normalization of body weight. These results demonstrate that leptin decreases the reward value of HFD independently of obesity, suggesting that leptin reduces food intake by suppressing the hedonic feeding pathway in ob/ob mice.

Free Research Field

内分泌代謝内科学