Effect of thioglycollate and BCG stimuli on glucose and glutamine metabolism in rat macrophages.

The macrophage is a differentiated cell that takes part in a wide range of physiological and pathological processes, such as inflammatory and immunological responses. The stimulation of macrophages involves the acquisition of some functional characteristics such as phagocytosis, ability to kill tumor cells, and processing and presentation of antigens. In this study we have investigated the changes in macrophage glucose and glutamine metabolism as induced by stimulation by thioglycollate (inflammatory) and bacille Calmette-Guérin (BCG) (activated). The results showed an increase in hexokinase and citrate synthase activities, due to both stimulatory processes. One difference between inflammatory and activated cells is the higher rate of glucose oxidation in the latter. The activation with BCG, however, also led to an enhancement in glutamine metabolism that is not observed in the inflammatory cell. These results suggest that glutamine metabolism might be important for macrophage function during immunological response.