Red blood cell dysfunction in septic glucose-6-phosphate dehydrogenase-deficient mice

Glucose-6-phosphate dehydrogenase (G-6-PDH) deficiency is the most common known human genetic polymorphism. This study tested the hypothesis that G-6-PDH deficiency worsens sepsis-induced erythrocyte dysfunction. Sepsis (24 h) was induced by cecal ligation and puncture in wild-type (WT) and G-6-PDH-deficient (G-6-PDH activity 15% of WT) mice. Erythrocyte responses were tested in whole blood as well as in subpopulations of circulating erythrocytes. Whereas erythrocyte deformability was similar in unchallenged deficient and WT animals, sepsis decreased erythrocyte deformability that was more pronounced in deficient than WT animals. Sepsis also resulted in anemia and hemolysis in deficient compared with WT animals. Mean corpuscular hemoglobin content and erythrocyte deformability decreased in younger erythrocyte subpopulations from septic deficient compared with WT animals. Sepsis decreased the reduced-to-oxidized glutathione ratio in erythrocytes from both deficient and WT animals; however, plasma glutathione increased more in deficient than in WT animals. Erythrocyte content of band 3 associated with the cytoskeleton was elevated in deficient compared with WT erythrocytes. The antioxidant N-acetyl-l-cysteine in vivo alleviated the sepsis-induced decrease in erythrocyte deformability in deficient animals compared with sham-operated control animals. This study demonstrates that a mild degree of G-6-PDH deficiency (comparable to the human class III G-6-PDH deficiencies) worsens erythrocyte dysfunction during sepsis. Increased erythrocyte rigidity and tendency for hemolysis together with alterations in band 3-spectrin interactions may contribute to the immunomodulatory effects of G-6-PDH deficiency observed after major trauma and infections in humans.