Project/Area Number |
20590729
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Gastroenterology
|
Research Institution | Nagasaki University |
Principal Investigator |
OHTSURU Akira Nagasaki University, 病院, 准教授 (00233198)
|
Co-Investigator(Kenkyū-buntansha) |
ICHIKAWA Tatsuki 長崎大学, 病院, 助教 (80346949)
KUMAGAI Atsushi 長崎大学, 病院, 助教 (40448494)
|
Project Period (FY) |
2008 – 2010
|
Project Status |
Completed (Fiscal Year 2010)
|
Budget Amount *help |
¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2010: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
Fiscal Year 2009: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Fiscal Year 2008: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
|
Keywords | グレリン / 光同調性概日リズム / 食事同調性概日リズム / レプチン / インスリン感受性 / β酸化代謝経路 / 食事同調性 / 光同調性 / 血糖 / レプチン感受性 / 脂肪酸 / 概日リズム / コルチゾール / インスリン |
Research Abstract |
The physiological circadian rhythm corresponding to a synchronous food-anticipatory activity has not been demonstrated in human studies. The plasma ghrelin level characteristically shows four peaks per day, compared to the typical one peak of other hormones based on light-entrainable circadian rhythm. We examined whether ghrelin secretion is mainly controlled by food-entrainable circadian rhythm or metabolic factors. Fourteen healthy subjects received a regular diet with three meals at fixed times for 14 days. Blood was collected from an intravenous brachial catheter every 60 min between 7:00 and 20:00 on the 1st and 14th study day. There were no significant differences in BMI and % body fat during the 2-week period with fixed meal times. There were no meaningful differences between the average 7:00 to 20:00 ghrelin, blood glucose, and cortisol levels, but the leptin and insulin levels were significantly lower on Day 14 than on the Day 1. Following a fixed feeding schedule for the 2-week period resulted in a regular ghrelin circadian rhythm reflecting a periodic pre-meal elevation instead of an individually irregular pattern (coefficient of variation of Day 1 vs. Day 14, 0.64±0.10 vs. 0.49±0.06 ; p<0.01). The circadian patterns of blood glucose, insulin, leptin, and cortisol showed no significant differences between Day 14 and Day 1. The results of the present study show that, in healthy adults, a regular eating habit can create a ghrelin-based, food-entrainable circadian rhythm, which might be related to reductions in leptin and insulin resistance.
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