Smith Mackenzie E, Bazinet Richard P
Department of Nutritional Sciences, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
Department of Nutritional Sciences, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
Prog Lipid Res. 2024 Nov;96:101300. doi: 10.1016/j.plipres.2024.101300. Epub 2024 Aug 31.
In the human brain, palmitic acid (16:0; PAM) comprises nearly half of total brain saturates and has been identified as the third most abundant fatty acid overall. Brain PAM supports the structure of membrane phospholipids, provides energy, and regulates protein stability. Sources underlying the origin of brain PAM are both diet and endogenous synthesis via de novo lipogenesis (DNL), primarily from glucose. However, studies investigating the origin of brain PAM are limited to tracer studies utilizing labelled (C/C/H/H) PAM, and results vary based on the model and tracer used. Nevertheless, there is evidence PAM is synthesized locally in the brain, in addition to obtained directly from the diet. Herein, we provide an overview of brain PAM origin, entry to the brain, metabolic fate, and factors influencing brain PAM kinetics and levels, the latter in the context of age, as well as neurological diseases and psychiatric disorders. Additionally, we briefly summarize the role of PAM in signaling at the level of the brain. We add to the literature a rudimentary summary on brain PAM metabolism.
在人类大脑中，棕榈酸（16:0；PAM）占大脑饱和脂肪酸总量的近一半，并且已被确定为总体上第三丰富的脂肪酸。脑内的PAM维持膜磷脂结构、提供能量并调节蛋白质稳定性。脑内PAM的来源包括饮食以及通过从头脂肪生成（DNL）的内源性合成，主要来源于葡萄糖。然而，研究脑内PAM来源的研究仅限于使用标记的（C/C/H/H）PAM的示踪研究，并且结果因所使用的模型和示踪剂而异。尽管如此，有证据表明PAM除了直接从饮食中获取外，还在脑内局部合成。在此，我们概述了脑内PAM的来源、进入大脑的途径、代谢命运以及影响脑内PAM动力学和水平的因素，后者是在年龄、神经疾病和精神疾病的背景下。此外，我们简要总结了PAM在大脑水平信号传导中的作用。我们在文献中增加了关于脑内PAM代谢的初步总结。
