Ascorbic acid efflux from human brain microvascular pericytes: role of re-uptake.

  title={Ascorbic acid efflux from human brain microvascular pericytes: role of re-uptake.},
  author={J. M. May and Z. Qu},
  volume={41 5},
Microvascular pericytes take up ascorbic acid on the ascorbate transporter SVCT2. Intracellular ascorbate then protects the cells against apoptosis induced by culture at diabetic glucose concentrations. To investigate whether pericytes might also provide ascorbate to the underlying endothelial cells, we studied ascorbate efflux from human pericytes. When loaded with ascorbate to intracellular concentrations of 0.8-1.0 mM, almost two-thirds of intracellular ascorbate effluxed from the cells over… Expand
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Ascorbic acid transport in brain microvascular pericytes.
The data clarify previous inconsistencies in the literature, implicate SVCT2 as the pericyte ascorbate transporter, and show that pericytes are capable of concentrating intracellular asCorbate against a gradient in an energy- and sodium-dependent fashion. Expand
Ascorbic acid efflux and re-uptake in endothelial cells: maintenance of intracellular ascorbate
  • J. M. May, Z. Qu
  • Chemistry, Medicine
  • Molecular and Cellular Biochemistry
  • 2008
Results support the hypothesis that ascorbate efflux reflects trans-endothelial cell asCorbate movement out of the blood vessel, and suggest that efflux of the vitamin was countered in part by its re-uptake on ascorBate transporters. Expand
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