Anticipatory changes in liver metabolism and entrainment of insulin, glucagon, and corticosterone in food-restricted rats
Anticipatory changes in liver metabolism and entrainment of insulin, glucagon, and corticosterone in food-restricted rats
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DOI：
10.1152/ajpregu.2000.279.6.r2048
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发表时间：
2000-12-01
影响因子：
2.8
通讯作者：
Escobar, C
中科院分区：
文献类型：
--
作者：
Díaz-Muñoz, M;Vázquez-Martínez, O;Escobar, C
有限的喂养时间表夹带的行为和生理昼夜节律，这取决于一个食物振荡器（FEO）。其机制可能与消化和内分泌调节能量平衡有关。本研究的特点是动态的循环皮质酮，胰岛素和胰高血糖素和调节参数的肝脏代谢的大鼠在限制喂养时间表。相对于自由采食对照，限食大鼠显示：1）进食前皮质酮和胰高血糖素增加，胰岛素减少，表明主要分解代谢状态; 2）乳酸/丙酮酸和β-羟基丁酸/乙酰乙酸比值降低，表明肝脏代谢中细胞质和线粒体氧化还原状态。所有这些变化在喂食后都被逆转。此外，尽管腺嘌呤核苷酸增加，但食物限制大鼠的肝脏能荷在进食前并未显示出显着变化，但在进食后显示出显着下降。在食物限制大鼠的肝脏中检测到的变化与24小时禁食下普遍存在的变化不同。这些观察结果表明，肝脏代谢的“预期活动”，以优化营养物质的处理，以每日喂养。数据还表明肝脏和内分泌信号与FEO的可能关系。
Restricted feeding schedules entrain behavioral and physiological circadian rhythms, which depend on a food-entrainable oscillator (FEO). The mechanism of the FEO might depend on digestive and endocrine processes regulating energy balance. The present study characterizes the dynamics of circulating corticosterone, insulin, and glucagon and regulatory parameters of liver metabolism in rats under restricted feeding schedules. With respect to ad libitum controls, food-restricted rats showed 1) an increase in corticosterone and glucagon and a decrease in insulin before food access, indicating a predominant catabolic state; and 2) a reduction in lactate-to-pyruvate and beta -hydroxybutyrate-to-acetoacetate ratios, indicating an oxidized cytoplasmic and mitochondrial redox state in the liver metabolism. All these changes were reversed after feeding. Moreover, liver energy charge in food-restricted rats did not show a significant modification before feeding, despite an increase in adenine nucleotides, but showed an important decrease after food intake. Variations detected in the liver of food-restricted rats are different from those prevailing under 24-h fasting. These observations suggest "anticipatory activity" of the liver metabolism to optimize the processing of nutrients to daily feeding. Data also suggest a possible relationship of the liver and endocrine signals with the FEO.