Copper ions potentiate a decrease in the mitochondrial membrane potential in cultured cerebellar granule neurons during glucose deprivation

Abstract

We showed that glucose deprivation for 35 min induces a decrease in the mitochondrial membrane potential in cultured cerebellar granule neurons, which was enhanced in the presence of 10 μM copper ions (Cu²⁺). It was associated with an increase in the free-radical level that was not affected by the noncompetitive antagonist of glutamate NMDA receptors MK-801, which prevents subsequently developing neuronal loss. However, in the presence of glucose, Cu²⁺ did not affect cell viability. Thus, Cu²⁺ induced stronger oxidative stress during glucose deprivation than in the presence of glucose, which, in turn, results in mitochondrial damage, glutamate release, glutamate receptor hyperstimulation, and neuronal loss.