title: Role of spermidine in the expression of late markers of adipose conversion. Effects of growth hormone.
abstract: Confluent Ob1771 cells treated with an inhibitor of spermidine and spermine synthesis, methylglyoxyal bis(guanylhydrazone), were dependent on putrescine addition for the expression of glycerol-3-phosphate dehydrogenase and acyl-CoA synthetase, which behaved as late markers of adipose conversion. A similar dependence was observed with drug-treated Ob17MT18 and 3T3-F442A preadipocyte cells, but not with non-differentiating 3T3-C2 cells. Studies in drug-treated Ob1771 cells at the mRNA level showed that the parallel expression of mRNAs encoding for glycerol-3-phosphate dehydrogenase and an homologue of serine proteinases of Mr 28,000 [Cook, Groves, Min & Spiegelman (1985) Proc. Natl. Acad. Sci. U.S.A. 82, 6480-6484] was also dependent on putrescine addition. Double-isotope experiments with [14C]putrescine and [3H]spermidine, as well as analysis of the polyamine content in drug-treated Ob1771 cells under various conditions, demonstrate after putrescine addition that the expression of late markers of adipose conversion was highly correlated with a 2-fold increase in the intracellular concentration of spermidine. No correlation was observed with changes in the intracellular concentrations of putrescine and spermine. Long-term exposure of untreated Ob1771 cells to growth hormone, which led to the expression of late markers of adipose conversion [Doglio, Dani, Grimaldi & Ailhaud (1986) Biochem. J. 238, 123-129] was also accompanied by the same increase in spermidine concentration, which attained values identical with those determined in drug-treated cells supplemented with putrescine. This observation suggests that the permissive effect of growth hormone on the terminal differentiation of adipose cells might e related to changes in the intracellular concentration of spermidine.
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism*; D002454:Cell Differentiation; D002460:Cell Line; D003066:Coenzyme A Ligases / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation; D005993:Glycerolphosphate Dehydrogenase / Q000378:metabolism; D013006:Growth Hormone / Q000494:pharmacology*; D008071:Lipoprotein Lipase / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism / Q000494:pharmacology; D011700:Putrescine / Q000494:pharmacology; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D013095:Spermidine / Q000502:physiology*; D000098859:Long-Chain-Fatty-Acid-CoA Ligase
chemical_list: D011073:Polyamines; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D013006:Growth Hormone; D005993:Glycerolphosphate Dehydrogenase; D008071:Lipoprotein Lipase; D003066:Coenzyme A Ligases; C090799:FAA2 protein, S cerevisiae; D000098859:Long-Chain-Fatty-Acid-CoA Ligase; D013095:Spermidine; D011700:Putrescine