Aims

We sought to evaluate the effects of overfeeding during lactation on the feeding behavior and expression of specific regulatory genes in brain areas associated with food intake in 22- and 60-day old male rats.

Methods

We evaluated body weight, food intake of standard and palatable diet, and mRNA expression of dopamine receptor D1 (DDR1), dopamine receptor (DDR2), melanocortin 4 receptor (MC4R), the μ-opioid receptor (MOR), neuropeptide Y (NPY), agouti-related protein (AGRP), proopiomelanocortin (POMC), cocaine-and amphetamine-regulated transcript (CART), serotonin (5-hydroxytryptamine; 5-HT) transporter (SERT), 5-hydroxytryptamine receptor 1B (5-HT1B), 5-hydroxytryptamine receptor 2C receptor (5-HT2C), Clock (CLOK), cryptochrome protein 1 (Cry1) and period circadian protein homolog 2 (Per2) in the striatum, hypothalamus and brainstem of male rats at post-natal days (PND) 22 and 60.

Key findings

Overfeeding resulted in significantly increased body weight through PND60, and a 2-fold increase in palatable food intake at PND22, but not at PND60. We observed significant increases in DDR1, DDR2, and MC4R gene expression in the striatum and brainstem and POMC/CART in the hypothalamus of the OF group at PND22 that were reversed by PND60. Hypothalamic levels of 5-HT1B, 5-HT2C and NPY/AGRP on the other hand were decreased at PND22 and increased at PND60 in OF animals. Clock genes were unaffected by OF at PND22, but were significantly elevated at PND60.

Significance

Overfeeding during early development of the rat brain results in obesity and altered feeding behavior in early adulthood. The altered behavior might be the consequence of the changes in food intake and reward gene expression.

中文翻译：

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发育过程中的过度喂养会导致雄性 Wistar 大鼠大脑中控制食物摄入的区域发生时间依赖性变化

宗旨

我们试图评估哺乳期间过度喂养对摄食行为和与 22 天和 60 天大的雄性大鼠食物摄入相关的大脑区域中特定调节基因表达的影响。

方法

我们评估了体重、标准和可口饮食的食物摄入量以及多巴胺受体 D1 (DDR1)、多巴胺受体 (DDR2)、黑皮质素 4 受体 (MC4R)、μ-阿片受体 (MOR)、神经肽 Y (NPY) 的 mRNA 表达)、刺鼠相关蛋白 (AGRP)、阿黑皮素原 (POMC)、可卡因和苯丙胺调节的转录物 (CART)、血清素（5-羟色胺；5-HT）转运蛋白 (SERT)、5-羟色胺受体 1B (5-HT1B) )、雄性大鼠出生后纹状体、下丘脑和脑干中的 5-羟色胺受体 2C 受体 (5-HT2C)、时钟 (CLOK)、隐花色素蛋白 1 (Cry1) 和周期昼夜节律蛋白同源物 2 (Per2)（ PND) 22 和 60。

主要发现

过度喂养通过 PND60 导致体重显着增加，并且在 PND22 时可口的食物摄入量增加了 2 倍，但在 PND60 时则不然。我们观察到 PND22 处 OF 组下丘脑纹状体和脑干以及 POMC/CART 中 DDR1、DDR2 和 MC4R 基因表达的显着增加，这些表达被 PND60 逆转。另一方面，OF 动物的 5-HT1B、5-HT2C 和 NPY/AGRP 的下丘脑水平在 PND22 时降低，而在 PND60 时升高。时钟基因在 PND22 时不受 OF 影响，但在 PND60 时显着升高。

意义

在大鼠大脑的早期发育过程中过度喂养会导致肥胖和成年早期进食行为的改变。改变的行为可能是食物摄入和奖励基因表达变化的结果。