Large V, Peroni O, Letexier D, Ray H, Beylot M
INSERM 499, Faculté de médecine Laennec, rue Paradin, 69372 Lyon.
Diabetes Metab. 2004 Sep;30(4):294-309. doi: 10.1016/s1262-3636(07)70121-0.
Adipose tissue is considered as the body's largest storage organ for energy in the form of triacylglycerols, which are mobilized through lipolysis process, to provide fuel to other organs and to deliver substrates to liver for gluconeogenesis (glycerol) and lipoprotein synthesis (free fatty acids). The release of glycerol and free fatty acids from human adipose tissue is mainly dependent on hormone-sensitive lipase which is intensively regulated by hormones and agents, such as insulin (inhibition of lipolysis) and catecholamines (stimulation of lipolysis). A special attention is paid to the recently discovered perilipins which could regulate the activity of the lipase hormono-sensible. Most of the plasma triacylglycerols are provided by dietary lipids, secreted from the intestine in the form of chylomicron or from the liver in the form of VLDL. Released into circulation as non-esterified fatty acids by lipoprotein lipase, those are taken up by adipose tissue via specific plasma fatty acid transporters (CD36, FATP, FABPpm) and used for triacylglycerol synthesis. A small part of triacylglycerols is synthesized into adipocytes from carbohydrates (lipogenesis) but its regulation is still debated in human. Physiological factors such as dieting/fasting regulate all these metabolic pathways, which are also modified in pathological conditions e.g. obesity.
脂肪组织被认为是人体最大的以三酰甘油形式储存能量的器官，三酰甘油通过脂解过程被动员起来，为其他器官提供燃料，并将底物输送到肝脏用于糖异生（甘油）和脂蛋白合成（游离脂肪酸）。人脂肪组织中甘油和游离脂肪酸的释放主要依赖于激素敏感脂肪酶，该酶受到激素和药物的严格调控，如胰岛素（抑制脂解）和儿茶酚胺（刺激脂解）。人们特别关注最近发现的围脂滴蛋白，它可以调节激素敏感脂肪酶的活性。大多数血浆三酰甘油由膳食脂质提供，以乳糜微粒的形式从肠道分泌或以极低密度脂蛋白的形式从肝脏分泌。脂蛋白脂肪酶将其以非酯化脂肪酸的形式释放到循环中，这些脂肪酸通过特定的血浆脂肪酸转运蛋白（CD36、脂肪酸转运蛋白、微粒体脂肪酸结合蛋白）被脂肪组织摄取，并用于三酰甘油合成。一小部分三酰甘油由碳水化合物合成进入脂肪细胞（脂肪生成），但其调节在人体中仍存在争议。生理因素如节食/禁食会调节所有这些代谢途径，在肥胖等病理状况下这些途径也会发生改变。
