Stanton L A, van de Venter M, Oelofsen W
Department of Biochemistry and Microbiology, University of Port Elizabeth, South Africa.
Comp Biochem Physiol B Biochem Mol Biol. 1998 Jul;120(3):507-16. doi: 10.1016/s0305-0491(98)10037-8.
3T3-L1 and human preadipocyte differentiation was significantly (P < 0.001) enhanced by HDL2, LDLII/III and LDLIV. The concentrations of lipoproteins required for maximal differentiation in human preadipocytes were not achieved over the concentration range 50-150 micrograms lipoprotein protein ml-1, whereas maximal differentiation in 3T3-L1 preadipocytes was achieved for all lipoprotein subfractions at approximately 75 micrograms lipoprotein ml-1, a level almost double that required for complete HDL and LDL fractions in 3T3-L1 cells. Despite the enhanced extent of differentiation caused by certain lipoprotein subfractions, the time needed for the conversion process was unaffected. GPDH activity development in both cell types was most pronounced in response to LDLIV, with HDL2 resulting in the lowest activity. In both cell types, the enhancement of differentiation was only evident when the cells were exposed to lipoproteins during the early stage of the program, i.e. before visible formation of lipid droplets.
HDL2、LDLII/III和LDLIV可显著（P < 0.001）增强3T3-L1和人前脂肪细胞的分化。在50 - 150微克脂蛋白蛋白每毫升的浓度范围内，人前脂肪细胞实现最大分化所需的脂蛋白浓度并未达到，而3T3-L1前脂肪细胞在所有脂蛋白亚组分约75微克脂蛋白每毫升时实现最大分化，这一水平几乎是3T3-L1细胞中完整HDL和LDL组分所需水平的两倍。尽管某些脂蛋白亚组分导致分化程度增强，但转化过程所需时间未受影响。两种细胞类型中甘油磷酸脱氢酶（GPDH）活性的发展对LDLIV反应最为明显，HDL2导致的活性最低。在两种细胞类型中，只有当细胞在程序早期即脂质小滴可见形成之前暴露于脂蛋白时，分化增强才明显。
