Lipid peroxidation and hemoglobin degradation in red blood cells exposed to t-butyl hydroperoxide. Dependence on glucose metabolism and hemoglobin status.

ABSTRACT

Changes in hemoglobin status and lipid peroxidation were followed in red cells containing either oxy-met-, or carbonmonoxyhemoglobin, incubated with t-butyl hydroperoxide in a medium with or without glucose. Loss of intact hemoglobin (the sum of oxyhemoglobin and methemoglobin) was inversely proportional to the degree of lipid peroxidation in red cells containing either oxy- or methemoglobin. When glucose was added to the medium, lipid peroxidation increased while there was a decreased loss of intact hemoglobin in red cells containing either oxy- or methemoglobin, while both lipid peroxidation and changes in hemoglobin decreased in red cells containing carbonmonoxyhemoglobin. Methemoglobin formation and loss of intact hemoglobin were directly proportional to the degree of lipid peroxidation in red cells containing carbonmonoxyhemoglobin. The greatest amount of lipid peroxidation occurred in red cells containing carbonmonoxyhemoglobin, incubated without glucose. These results indicate that methemoglobin and non-intact hemoglobin may protect the membrane against lipid peroxidation. We propose that, depending on the availability of glucose and the liganded state of hemoglobin, lipid peroxidation and hemoglobin alterations represent extremes of a spectrum of oxidative damage.