Neurosciences Intégratives et Cliniques EA481, Université de Bourgogne Franche-Comté (UBFC), 25000 Besançon, France.
Unité Inserm U1234, Université de Rouen/IRIB, Faculté de Médecine et Pharmacie, 76183 Rouen CEDEX, France.
Nutrients. 2018 Sep 6;10(9):1246. doi: 10.3390/nu10091246.
The origin of spontaneous preference for dietary lipids in humans and rodents is debated, though recent compelling evidence has shown the existence of fat taste that might be considered a sixth taste quality. We investigated the implication of gustatory and reward brain circuits, triggered by linoleic acid (LA), a long-chain fatty acid. The LA was applied onto the circumvallate papillae for 30 min in conscious C57BL/6J mice, and neuronal activation was assessed using c-Fos immunohistochemistry. By using real-time reverse transcription polymerase chain reaction (RT-qPCR), we also studied the expression of mRNA encoding brain-derived neurotrophic factor (BDNF), Zif-268, and Glut-1 in some brain areas of these animals. LA induced a significant increase in c-Fos expression in the nucleus of solitary tract (NST), parabrachial nucleus (PBN), and ventroposterior medialis parvocellularis (VPMPC) of the thalamus, which are the regions known to be activated by gustatory signals. LA also triggered c-Fos expression in the central amygdala and ventral tegmental area (VTA), involved in food reward, in conjunction with emotional traits. Interestingly, we noticed a high expression of BDNF, Zif-268, and Glut-1 mRNA in the arcuate nucleus (Arc) and hippocampus (Hipp), where neuronal activation leads to memory formation. Our study demonstrates that oral lipid taste perception might trigger the activation of canonical gustatory and reward pathways.
人类和啮齿动物对膳食脂质的自发偏好的起源存在争议，尽管最近有强有力的证据表明存在脂肪味觉，它可能被认为是第六种味觉质量。我们研究了味觉和奖励脑回路的含义，这些回路是由长链脂肪酸亚油酸（LA）触发的。在有意识的 C57BL/6J 小鼠中，LA 在 30 分钟内应用于环状乳突，并用 c-Fos 免疫组织化学评估神经元激活。通过实时逆转录聚合酶链反应（RT-qPCR），我们还研究了这些动物某些脑区中脑源性神经营养因子（BDNF）、Zif-268 和 Glut-1 的 mRNA 表达。LA 诱导孤束核（NST）、臂旁核（PBN）和丘脑腹后内侧小细胞区（VPMPC）中 c-Fos 表达显著增加，这些区域已知可被味觉信号激活。LA 还在参与食物奖励的杏仁中央核和腹侧被盖区（VTA）中触发 c-Fos 表达，同时与情绪特征相关。有趣的是，我们注意到在弓状核（Arc）和海马（Hipp）中 BDNF、Zif-268 和 Glut-1 mRNA 的高表达，神经元激活导致记忆形成。我们的研究表明，口腔脂质味觉感知可能触发经典味觉和奖励途径的激活。
