Millimolar concentrations of ascorbic acid in purified human mononuclear leukocytes. Depletion and reaccumulation.

  title={Millimolar concentrations of ascorbic acid in purified human mononuclear leukocytes. Depletion and reaccumulation.},
  author={Peter Bergsten and Gabriel Amitai and John H. Kehrl and Kuldeep R. Dhariwal and Harvey G Klein and Mark A Levine},
  journal={The Journal of biological chemistry},
  volume={265 5},
Ascorbic acid (vitamin C) was found in isolated human mononuclear leukocytes and their purified components in millimolar concentration. Intracellular ascorbic acid was depleted greater than 96% during cell culture and was rapidly reaccumulated after addition of physiologic concentrations of ascorbic acid to the extracellular medium. Purified cells maintained concentration gradients of ascorbic acid as large as 100-fold across the plasma membrane. The ability to vary intracellular ascorbic acid… Expand
Vitamin C recycling and function in human monocytic U-937 cells.
U-937 cells loaded with dehydroascorbic acid accumulate ascorbate against a concentration gradient via a mechanism that is not dependent on GSH or NADPH, and this asCorbate can serve as the major source of electrons for transfer across the plasma membrane to extracellular ferricyanide. Expand
Modulation of interleukin production by ascorbic acid.
The results suggest that ascorbate levels exert an early effect on immune homeostasis via reactive oxygen intermediates (ROI)-dependent expression of interleukin genes, since the transcription factor NF-kappa B is sensitive to ROI and regulates the expression of IL-2 genes. Expand
Effect of sodium ascorbate on the chemiluminescent response of murine peritoneal exudate cells.
These studies show that physiological doses of sodium ascorbate can quench CL in vitro, but even large doses of salt administered in vivo do not affect the CL of harvested murine PEC. Expand
Macrophage uptake and recycling of ascorbic acid: response to activation by lipopolysaccharide.
Results show that macrophages maintain millimolar concentrations of ascorbate through function of the SVCT2 and that activated cells have an enhanced ability to transport and recycle ascorBate, possibly reflecting its role as an intracellular antioxidant. Expand
Role of ascorbic acid in transferrin-independent reduction and uptake of iron by U-937 cells.
Extracellular ascorbate derived from cells can enhance transferrin-independent iron uptake by reducing ferric to ferrous iron, but intracellular asCorbate neither contributes to this reduction nor modifies the redox status of intrACEllular free iron. Expand
Preferential uptake and accumulation of oxidized vitamin C by THP-1 monocytic cells.
The preferential uptake of the dehydro-form of the vitamin may be useful for situations where this short-lived metabolite is formed by oxidation in the environment. Expand
Assessing the reductive capacity of cells by measuring the recycling of ascorbic and lipoic acids.
  • J. M. May
  • Chemistry, Medicine
  • Methods in molecular biology
  • 2010
Methods have been developed to assess the ability of intact cells to recycle ascorbate and to generate intracellular reducing equivalents required to maintain the redox status of the cells. Expand
Vitamin C enters mouse T cells as dehydroascorbic acid in vitro and does not recapitulate in vivo vitamin C effects.
Application of vitamin C to T cells in vitro did not recapitulate previously reported in vivo responses to vitamin C, suggesting that in vivo, vitamin C modulates T cells indirectly through other components of the microenvironment. Expand
In vitro differentiation of human monocytes to macrophages results in depletion of antioxidants and increase in n‐3 fatty acids levels
Changes in vitamin E and fatty acids contents in macrophages, with respect to monocytes, appear to reflect the lipid composition of fetal calf serum, that is low initamin E and has a proportionally higher docosahexaenoic acid content than adult human serum. Expand
Functions of vitamin C as a mediator of transmembrane electron transport in blood cells and related cell culture models.
The various pathways of regeneration of ascorbate and their relative contributions to the avoidance of vitamin loss in plasma or cell culture medium are discussed. Expand