- 作者: Daniel Tsun-Yee Chiu; Tsan Zon Liu
- 作者服務機構: a School of Medical Technology, Chang Gung College of Medicine and Technology,Taoyuan, and ; b Department of Medical Research and Clinical Laboratory, Yuan's General Hospital, Kaohsiung, Taiwan
- 中文摘要: --
- 英文摘要: Free radicals and oxidative damage play important roles in aging and many degenerative disorders such as cancer, cardiovascular diseases, and Alzheimer disease. Antioxidants can alleviate some of the harmful effects of oxidative damage. In this report, we describe that we have been using human red blood cells (RBCs) as a model system to delineate the effects of oxidative damage on human cells, particularly on glucose-6-phosphate dehydrogenase (G6PD)-deficient human RBCs. By using a monolayer technique, we found that oxidative denaturation of hemoglobin leads to the release of hemin into the RBC membrane and the released hemin is capable of oxidizing membrane proteins via a thiyl radical intermediate as detected by the electron spin resonance technique. By using a Laser Viscodiffractometer (Vidometer) to measure RBC deformability, we found that the deformability of G6PD-deficient RBCs was drastically reduced by hydroxyl radicals. Perhaps as a consequence of enhanced susceptibility to oxidative stress, G6PD-deficient individuals have lower antioxidant levels, particularly vitamin C, than normal individuals. Interestingly, we have also found that RBC deformability could be affected by two environmental pollutants, namely, platinum and palladium, which can enhance hydroxyl radical formation in the presence of hydrogen peroxide and ferrous ion (Fenton reaction).
- 中文關鍵字: --
- 英文關鍵字: Free radical ; Oxidative damage ; Red blood cells ; Hemin; Fenton reaction; Glucose-6-phosphate dehydrogenase; Palladium; Platinum