Abstract

Vitamin C is the major antioxidant molecule in the central nervous system (CNS), reaching concentrations of 10 mM in neurons and 400 μM in the cerebrospinal fluid (CSF). Uptake of vitamin C by brain cells is performed through the co‐transporter of ascorbic acid and sodium isoform 2, SVCT2, which is expressed in cells from the choroid plexus, neurons, oligodendrocytes, and ependymal cells. SVCT2 expression has also been described in cells at the neurogenic niche, specifically in proliferative type C cells. In this chapter, we will describe recently published studies of SVCT2 expression during brain development and define its polarization in cells from the radial glia (neuronal precursors within the CNS) and vitamin C‐mediated effects in regulating genes associated with the maintenance of CNS stem cell pluripotency. We will discuss the differential biological effect that vitamin C generates in neurons versus astrocytes and how the oxidized form of vitamin C, dehydroascorbic acid (DHA), produced by neurons in conditions of oxidative stress must leave this cell to be incorporated by astrocytes. In this context, we will discuss recent literature, which shows that DHA regulates glycolytic metabolism in neurons. In parallel, we will analyze vitamin C recycling by astrocytes, which reduce DHA into ascorbic acid (AA), increasing the antioxidant potential of the brain. Data discussed in this chapter will provide an updated view of SVCT2 distribution in the brain and will also describe how vitamin C recycling participates in normal or pathological brain function.