In AD, decreased brain glucose uptake correlates with lower expression levels of the glucose transporters GLUT1 and neuronal GLUT3 [187,188,189], as well as with diminished activities of different metabolic enzymes such as glucose-6-phosphate isomerase, lactate dehydrogenase, phosphofruktinase, cytochrome oxidase, and α-ketoglutarate compared to the controls [173,178,190,191]. Here, SLC2A1 is linked to Alzheimer disease.