Old Things New View: Ascorbic Acid Protects the Brain in Neurodegenerative Disorders

Int J Mol Sci. 2015 Nov 27;16(12):28194-217. doi: 10.3390/ijms161226095.


Ascorbic acid is a key antioxidant of the Central Nervous System (CNS). Under brain activity, ascorbic acid is released from glial reservoirs to the synaptic cleft, where it is taken up by neurons. In neurons, ascorbic acid scavenges reactive oxygen species (ROS) generated during synaptic activity and neuronal metabolism where it is then oxidized to dehydroascorbic acid and released into the extracellular space, where it can be recycled by astrocytes. Other intrinsic properties of ascorbic acid, beyond acting as an antioxidant, are important in its role as a key molecule of the CNS. Ascorbic acid can switch neuronal metabolism from glucose consumption to uptake and use of lactate as a metabolic substrate to sustain synaptic activity. Multiple evidence links oxidative stress with neurodegeneration, positioning redox imbalance and ROS as a cause of neurodegeneration. In this review, we focus on ascorbic acid homeostasis, its functions, how it is used by neurons and recycled to ensure antioxidant supply during synaptic activity and how this antioxidant is dysregulated in neurodegenerative disorders.

Keywords: brain energy metabolism; oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Antioxidants / metabolism
  • Ascorbic Acid / metabolism*
  • Astrocytes / metabolism
  • Brain / metabolism*
  • Brain / pathology
  • Central Nervous System / metabolism
  • Central Nervous System / pathology
  • Energy Metabolism
  • Humans
  • Neurodegenerative Diseases / metabolism*
  • Neurodegenerative Diseases / pathology
  • Neurons / metabolism
  • Neuroprotective Agents / metabolism*
  • Oxidation-Reduction
  • Oxidative Stress
  • Reactive Oxygen Species / metabolism
  • Synapses / metabolism


  • Antioxidants
  • Neuroprotective Agents
  • Reactive Oxygen Species
  • Ascorbic Acid