Effects of alpha-ketoglutarate on neutrophil intracellular amino and alpha-keto acid profiles and ROS production

The aim of this study was to determine the effects of alpha-ketoglutarate on neutrophil (PMN), free alpha-keto and amino-acid profiles as well as important reactive oxygen species (ROS) produced [superoxide anion (O-2(-)), hydrogen peroxide (H2O2)] and released myeloperoxidase (MPO) acitivity. Exogenous alpha-ketoglutarate significantly increased PMN alpha-ketoglutarate, pyruvate, asparagine, glutamine, asparatate, glutamate, arginine, citrulline, alanine, glycine and serine in a dose as well as duration of exposure dependent manner. Additionally, in parallel with intracellular alpha-ketoglutarate changes, increases in O-2(-) formation, H2O2-generation and MPO acitivity have also been observed. We therefore believe that alpha-ketoglutarate is important for affecting PMN susceptible free amino- and alpha-keto acid pools although important mechanisms and backgrounds are not yet completely explored. Moreover, our results also show very clearly that changes in intragranulocytic alpha-ketoglutarate levels are relevant metabolic determinants in PMN nutrition considerably influencing and modulating the magnitude and quality of the granulocytic host defense capability as well as production of ROS.