Preferential uptake and accumulation of oxidized vitamin C by THP-1 monocytic cells.

  title={Preferential uptake and accumulation of oxidized vitamin C by THP-1 monocytic cells.},
  author={Hilde Laggner and V Besau and Hans Goldenberg},
  journal={European journal of biochemistry},
  volume={262 3},
THP-1 cells preferentially accumulate vitamin C in its oxidized form. The uptake displays first-order kinetics and leads to a build-up of an outward concentration gradient which is stable in the absence of extracellular vitamin. The transport is faster than reduction by extracellular glutathione or by added cytosolic extract, and glutathione-depleted cells show the same uptake rates as control cells. In addition, energy depletion or oxidation of intracellular sulfhydryls does not inhibit… 

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