Effect of oxidative stress on avian erythrocytes.
Avian erythrocytes differ from mammalian erythrocytes in being nucleated and oval. In the circulation, chicken cells survive for only 35 days, compared to 120 days for human cells. In humans, red cell oxidation processes, involving methemoglobin formation, have been correlated with cellular aging. This study compared oxidative resistance of two avian red cells (chicken and ostrich) to that of discoid enucleated human cells. Reduced glutathione levels (GSH) and methemoglobin were higher in chicken and ostrich cells than in human cells. SOD levels were higher in human cells. Diamide exposure diminished intracellular GSH levels in all species, with the greatest effect on human cells. Regeneration potential was high for all cells. Ostrich cells were more sensitive to hydrogen peroxide when hemoglobin oxidation was involved; BHP exposure affected GSH depletion and methemoglobin production in ostrich cells more than in the others. Lipid peroxidation was found to be highest in the human cells. Chicken cells were only slightly more resistant than human cells. Our data suggest that the extensive, complex oxidation by BHP cannot represent in vivo aging processes. In addition, the milder, selective oxidation by diamide affects human cells (endowed with long life span) more than avian cells. It is concluded that in vitro oxidation by diamide and BHP cannot be correlated with red cell survival.
el-Mekawi
S
S
Physiology Unit, Soroka Hospital Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel.
Yagil
R
R
Meyerstein
N
N
D000328:Adult; D000818:Animals; D001717:Birds / Q000097:blood*; D002645:Chickens; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D018384:Oxidative Stress / Q000502:physiology*