Article

Antioxidant and bioenergetic coupling between neurons and astrocytes

Department of Biochemistry and Molecular Biology, Institute of Neurosciences of Castilla y León, University of Salamanca, Salamanca 37007, Spain.
Biochemical Journal (Impact Factor: 4.4). 04/2012; 443(1):3-11. DOI: 10.1042/BJ20111943
Source: PubMed

ABSTRACT

Oxidative and nitrosative stress underlie the pathogenesis of a broad range of human diseases, in particular neurodegenerative disorders. Within the brain, neurons are the cells most vulnerable to excess reactive oxygen and nitrogen species; their survival relies on the antioxidant protection promoted by neighbouring astrocytes. However, neurons are also intrinsically equipped with a biochemical mechanism that links glucose metabolism to antioxidant defence. Neurons actively metabolize glucose through the pentose phosphate pathway, which maintains the antioxidant glutathione in its reduced state, hence exerting neuroprotection. This process is tightly controlled by a key glycolysis-promoting enzyme and is dependent on an appropriate supply of energy substrates from astrocytes. Thus brain bioenergetic and antioxidant defence is coupled between neurons and astrocytes. A better understanding of the regulation of this intercellular coupling should be important for identifying novel targets for future therapeutic interventions.

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    • "In brain, the astrocytes are considered to play a pivotal role in copper homeostasis [2] [8] [9]. Astrocytes represent one of the main brain cell types which fulfills as partner of neurons many important functions, including control of the extracellular environment [10], supply of metabolic substrates to neurons [11] [12], modulation of synaptic transmission and plasticity [13], and protection of the brain against damage caused by oxidants and toxins [14] [15]. "
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