FIGURE 1.

Fasting-induced hypoleptinema is associated with persistent functional and metabolic T cell defects. (A) Wildtype C57BL/6J mice were either fasted for 48 hours or allowed to feed ad libitum. All mice had full access to water. At the end of the fast, serum was collected from blood and circulating leptin levels were measured by ELISA. Data are representative of five independent experiments; three mice per group. (B and C) Peripheral T cells from control and fasted C57BL/6J mice were then cultured in complete media with full nutrients and activated with antibodies to CD3 and CD28 for 48 hours, after which IL-2 and IFN-γ were measured in culture supernatants by ELISA. Data are representative of six independent experiments, three mice per group. (D) Glucose uptake was assessed by ³[H]-2-DG uptake in both resting and activated peripheral T cells. Data are representative of two independent experiments for glycolysis, three mice per group. (E) Glycolytic flux was determined by the generation of tritiated water by enolase in both resting and activated peripheral T cells. Data are representative of two independent experiments for glycolysis, three mice per group.