Ascorbate levels in red blood cells and urine in patients with sickle cellanemia

Ascorbic acid can be important in sickle cell anemia (SCA) because signific ant oxidative stress occurs in the disease. Ascorbate could contribute to r eduction of the increased oxygen free radicals generated in sickle red bloo d cells (SRBC) and to the recycling of vitamin E in the cells, while renal loss could contribute to the low plasma levels. Evaluation of red blood cel l (RBC) and urine ascorbate in SCA has not been reported. Results showed (1 )ascorbate levels in SRBC were similar to those in normals; (2) urine ascor bate excretion was increased in 36% of patients; (3) plasma levels of ascor bate were decreased, Conclusions: (1) Ascorbate is present in SRBC, most li kely due to ascorbate recycling, despite increased free-radical generation, (2) The increase in renal excretion may contribute to the low plasma level s of ascorbate, (3) The presence of ample ascorbate in SRBC and decreased p lasma ascorbate suggests that ascorbate movement across the SRBC membrane m ay differ from normal RBC, (C) 2000 Wiley-Liss, Inc.