Gambert Ségolène, Ricquier Daniel
Biologie des transporteurs mitochondriaux et métabolisme, Université Paris Descartes, CNRS, Paris, France.
Curr Opin Clin Nutr Metab Care. 2007 Nov;10(6):664-70. doi: 10.1097/MCO.0b013e3282f0b69d.
Thermogenesis is activated at the expense of carbon molecules. Mitochondria play a dominant role in oxidation and parallel heat production since the recovery of oxidation energy is less than perfect. Recent data of mitochondriogenesis and mitochondrial thermogenesis may boost research into certain aspects of obesity.
Recent studies have outlined the unexpected decreased thermogenesis that limits fat loss during prolonged food restriction. Activation of fat oxidation in skeletal muscle remains a strategy against fat accumulation, however. Certain adipose depots have the potential to promote thermogenesis, either using mitochondrial uncoupling protein or independently. Peroxisome proliferator-activated receptor gamma coactivators alpha and ss are important regulators of mitochondria thermogenesis. Brain mitochondria are involved in the control of refeeding after starvation. This dual action of mitochondria inform their role in thermogenesis and energy partitioning. The importance of thyroid hormones in mitochondria thermogenesis is also confirmed.
The clinical and research implications of these findings are that the mechanisms inhibiting adaptive thermogenesis during diet restriction should be investigated. An important field of research is the contribution of transcriptional coactivators to adipocyte plasticity since adipocytes have an underestimated ability to oxidise fatty acids in addition to their role in triglyceride storage.
产热是以消耗碳分子为代价而被激活的。由于氧化能量的回收并不完美,线粒体在氧化及并行的产热过程中起主导作用。线粒体生成和线粒体产热的最新数据可能会推动肥胖某些方面的研究。
近期研究概述了长期食物限制期间限制脂肪减少的意外的产热减少情况。然而,激活骨骼肌中的脂肪氧化仍然是对抗脂肪堆积的一种策略。某些脂肪库有促进产热的潜力,要么通过线粒体解偶联蛋白,要么独立发挥作用。过氧化物酶体增殖物激活受体γ共激活因子α和β是线粒体产热的重要调节因子。脑线粒体参与饥饿后再进食的控制。线粒体的这种双重作用说明了它们在产热和能量分配中的作用。甲状腺激素在线粒体产热中的重要性也得到了证实。
这些发现的临床和研究意义在于,应研究饮食限制期间抑制适应性产热的机制。一个重要的研究领域是转录共激活因子对脂肪细胞可塑性的贡献,因为脂肪细胞除了在甘油三酯储存中发挥作用外,其氧化脂肪酸的能力被低估了。