Centre for Neural Circuits and Behaviour, The University of Oxford, Tinsley Building, Mansfield Road, Oxford OX1 3SR, UK.
Centre for Neural Circuits and Behaviour, The University of Oxford, Tinsley Building, Mansfield Road, Oxford OX1 3SR, UK.
Cell Rep. 2018 Sep 18;24(12):3194-3206.e4. doi: 10.1016/j.celrep.2018.08.059.
A balanced diet of macronutrients is critical for animal health. A lack of specific elements can have profound effects on behavior, reproduction, and lifespan. Here, we used Drosophila to understand how the brain responds to carbohydrate deprivation. We found that serine protease homologs (SPHs) are enriched among genes that are transcriptionally regulated in flies deprived of carbohydrates. Stimulation of neurons expressing one of these SPHs, Scarface (Scaf), or overexpression of scaf positively regulates feeding on nutritious sugars, whereas inhibition of these neurons or knockdown of scaf reduces feeding. This modulation of food intake occurs only in sated flies while hunger-induced feeding is unaffected. Furthermore, scaf expression correlates with the presence of sugar in the food. As Scaf and Scaf neurons promote feeding independent of the hunger state, and the levels of scaf are positively regulated by the presence of sugar, we conclude that scaf mediates the hedonic control of feeding.
均衡的宏量营养素饮食对动物健康至关重要。缺乏特定元素会对行为、繁殖和寿命产生深远影响。在这里，我们使用果蝇来了解大脑如何对碳水化合物缺乏做出反应。我们发现，丝氨酸蛋白酶同源物（SPH）在碳水化合物剥夺的果蝇中转录调控的基因中富集。刺激表达这些 SPH 之一的 Scarface（Scaf）的神经元，或过表达 scaf，可正向调节对营养糖的摄取，而抑制这些神经元或 scaf 的敲低则会减少摄取。这种对食物摄入的调节仅在饱腹的果蝇中发生，而饥饿诱导的进食不受影响。此外，scaf 的表达与食物中糖的存在相关。由于 Scaf 和 Scaf 神经元独立于饥饿状态促进进食，并且 scaf 的水平受到糖的存在的正向调节，我们得出结论，scaf 介导了进食的享乐控制。
