Early changes in glucose metabolism in the cerebrum of senescence accelerated mouse: involvement of glucose transporter

Abstract

The rate of 6-[ 14C] d-glucose oxidation in cerebral cells of SAMP8, a substrain of senescence accelerated mouse, was investigated in vitro. The production of 14CO 2 in dissociated intact brain cells prepared from the cerebrum of 4–8-week-old SAMP8 was higher than that of age-matched SAMR2 as a control mouse, while no difference between these two strains was observed in the production of 14CO 2 in the cerebral homogenates. These results indicated that the increased metabolism of glucose in SAMP8 might be associated with the glucose transport system across the cell membrane. Therefore, 2-deoxy- d-glucose (2-DG) uptake into the brain cells and cytochalasin B(CB) binding to cerebral crude membranes examined. Both the 2-DG uptake and the CB binding in SAMP8 were much greater than in SAMR2. Furthermore, the increased CB binding in SAMP8 was seen only in the cerebral cortex of 4- to 8-week-old mice, and neither in other regions of the cerebrum nor in other aged mice (2-week- and 40- to 48-week-old mice). These results suggest that the transient overproduction of the glucose transporter protein in the cerebral cortex is involved in the increased glucose metabolism in 4- to 8-week-old SAMP8.