Regulation of lipoprotein lipase synthesis and 3T3-L1 adipocyte metabolism by recombinant interleukin 1.
When fully differentiated 3T3-L1 adipocytes were exposed to purified, recombinant murine interleukin 1 (rIL-1), a dose-dependent suppression of lipoprotein lipase activity was observed. The loss of activity reached a maximum of 60-70% of control and appeared to be due to an effect on the synthesis of the enzyme as judged by a suppression of the ability to incorporate [35S]methionine into immunoprecipitable lipoprotein lipase. There was no general effect on protein synthesis as determined by radiolabel incorporation into acid precipitable protein; however, after a 17 h exposure of the 3T3-L1 cells to recombinant interleukin 1, the synthesis of two proteins (molecular weights, 19,400 and 165,000 daltons) was enhanced several-fold. When the effect of Il-1 on the major metabolic pathways of the adipocyte was investigated, lipolysis as measured by glycerol release from the cells was markedly enhanced after a 17 h incubation with the hormone, while no effect was observed on de novo fatty acid synthesis. These effects on the metabolism of the adipocytes occur at concentration on a basis of molecules per cell, similar (only a 3-fold difference) to those required for stimulation of [3H]thymidine incorporation into mouse thymocyte DNA, suggesting that IL-1 may be a physiologically significant effector of adipocyte metabolism.
D000273:Adipose Tissue / Q000187:drug effects* / Q000201:enzymology; D000818:Animals; D002460:Cell Line; D004261:DNA Replication / Q000187:drug effects; D005227:Fatty Acids / Q000096:biosynthesis; D007375:Interleukin-1 / Q000494:pharmacology*; D008066:Lipolysis / Q000187:drug effects; D008071:Lipoprotein Lipase / Q000096:biosynthesis*; D051379:Mice; D014176:Protein Biosynthesis; D011994:Recombinant Proteins / Q000494:pharmacology; D013726:Terbutaline / Q000494:pharmacology
D005227:Fatty Acids; D007375:Interleukin-1; D011994:Recombinant Proteins; D008071:Lipoprotein Lipase; D013726:Terbutaline