METABOLISM OF GLYCEROL-1,2,3-TRIMETHYLSUCCINATE IN RAT PANCREATIC-ISLETS

The metabolism of C-14-labelled glycerol-1,2,3-trimethylsuccinate (2.0 mM) was examined in rat pancreatic islets, The oxidation of the glyce rol moiety of the ester was negligible relative to that of its succina te residues, The oxidation of glycerol-1,2,3-trimethyl[1,4-C-14]succin ate was two times higher than that of glycerol-1,2,3-trimethyl[2,3-C-1 4]succinate, this difference being matched by a higher generation of C -14-labelled acidic metabolites and amino acids from the latter than F rom the former tracer, The total generation of (CO2)-C-14 from the est er, uniformly labelled except in its methyl groups, was close to that found for the oxidation of 1.0 mM D-[U-C-14]glucose. These findings th us reveal that glycerol-1,2,3-trimethylsuccinate is efficiently metabo lized in islet cells and support the idea that this ester could be use d as a nutrient to bypass defects of D-glucose transport and metabolis m in the islet B-cell and, hence, improve proinsulin biosynthesis and insulin release in non-insulin-dependent diabetes mellitus. (C) 1997 A cademic Press.