Salvayre R, Nègre A, Radom J, Douste-Blazy L
Laboratoire de Biochimie, Faculté de Médecine, Université Paul Sabatier, Toulouse, France.
FEBS Lett. 1989 Jun 19;250(1):35-9. doi: 10.1016/0014-5793(89)80679-9.
The functional relationship between the two subcellular compartments involved in catabolism of triglycerides, i.e. lysosomes and lipid-containing cytoplasmic vacuoles, has been investigated using cultured fibroblasts from patients affected with two different genetic lipid (triacylglycerol) storage disorders: Wolman disease and multisystemic lipid storage myopathy. As shown by metabolic studies in intact cultured cells, lysosomal degradation of exogenous labelled triacylglycerols (incorporated into lipoproteins and internalized via the apo B/E receptor pathway) was blocked in Wolman cells, whereas catabolism of endogenously biosynthesized triacylglycerols was in the normal range. In contrast, in fibroblasts from multisystemic lipid storage myopathy, the degradation of endogenous triacylglycerols was blocked, whereas that of exogenous triacylglycerols (i.e. from lipoproteins) was normal. This comparative study demonstrates that the lysosomal and cytoplasmic compartments are functionally independent. Enzymatic studies allows one to discriminate clearly between 3 lipases and 2 carboxylesterases the role of which is discussed.
利用来自患有两种不同遗传性脂质（三酰甘油）储存障碍患者的培养成纤维细胞，即沃尔曼病和多系统脂质储存性肌病，研究了参与甘油三酯分解代谢的两个亚细胞区室之间的功能关系。如在完整培养细胞中的代谢研究所示，沃尔曼细胞中溶酶体对外源标记三酰甘油（掺入脂蛋白并通过载脂蛋白B/E受体途径内化）的降解受阻，而内源性生物合成的三酰甘油的分解代谢在正常范围内。相反，在多系统脂质储存性肌病患者的成纤维细胞中，内源性三酰甘油的降解受阻，而外源性三酰甘油（即来自脂蛋白的）降解正常。这项比较研究表明，溶酶体区室和细胞质区室在功能上是独立的。酶学研究能够清楚地区分3种脂肪酶和2种羧酸酯酶，并对它们的作用进行了讨论。
