Persistent activation of N-methyl-D-aspartate (NMDA) subtype of glutamate receptors (NMDAR) is behind the pathogenesis of several neurological disorders, such as Alzheimer’s disease, amyotrophic lateral sclerosis or stroke (1). 6-Phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3) is a master activator of glycolysis by its ability to synthesize fructose-2,6-bisphosphate, a potent positive allosteric effector of 6-phosphofructo-1-kinase. Previous results from our laboratory have shown that, in neurons, PFKFB3 is constantly destabilized through the ubiquitin-proteasome pathway by the E3 ubiquitin ligase anaphase promoting complex/cyclosome-Cdh1 (APC/C-Cdh1), which acts on a PFKFB3-destabilizing KEN motif (2). Upon NMDAR stimulation, Cdh1 is phosphorylated by the cyclin-dependent kinase-5 (Cdk5) and accumulates in the cytosol, thus inhibiting APC/C activity (3). To investigate whether glutamate receptor activation regulates PFKFB3 stability, here we have incubated rat cortical neurons in primary culture with glutamate or NMDA (100 µM/15 minutes each), and the PFKFB3 protein abundance was assessed several hours later. We found that NMDAR activation promoted a progressive accumulation of PFKFB3 protein through a mechanism that involved the inhibition of APC/C-Cdh1. Furthermore, NMDAR-mediated increase in PFKFB3 stability yielded neurons having a higher glycolytic, and lower pentose-phosphate pathway (PPP) rates. By regenerating NADPH cofactor, PPP activity is known to be essential at maintaining the glutathione redox status; in good agreement with this notion, we found that stimulation of this NMDAR-PFKFB3 pathway led to oxidative stress and apoptotic neuronal death. Furthermore, these effects were counteracted by overexpression of the rate-limiting enzyme of the PPP, glucose-6-phosphate dehydrogenase. Finally, expression of a mutant form of PFKFB3 lacking the KEN motif was sufficient to trigger oxidative stress and apoptotic death of neurons. Together, these results demonstrate that, by inhibiting APC/C-Cdh1, NMDAR activation stabilizes PFKFB3, hence re-programming neuronal metabolism leading to oxidative damage and neurodegeneration.