Vitamin C suppresses the cisplatin toxicity on blood platelets

The effects of vitamin C on the oxidative stress in blood platelets induced by cisplatin were studied. In the presence of vitamin C we measured in blo od platelets the production of thiobarbituric acid reactive substances (TBA RS), the generation of superoxide radicals (O-2(.-)), other reactive oxygen species (H2O2, singlet oxygen and organic radicals) and catalase activity. Vitamin C at a low concentration (0.1 mM), like cisplatin (20 mu M), induc ed blood platelet oxidative stress: an increase of TBARS, chemiluminescence and generation of superoxide radicals. After treatment of blood platelets with vitamin C at a high concentration (3 mM), chemiluminescence (p>0.05), the levels of O-2(.-) (p<0.01) and TBARS (p<0.002) were reduced. We have sh own that vitamin C at a high concentration (3 mM) had a protective effect a gainst oxidative stress in platelets caused by cisplatin (20 mu M). It dimi nished platelet lipid peroxidation and reactive oxygen species generation i nduced by cisplatin. In the presence of vitamin C, the catalase activity wa s suppressed. [(C), 2000 Lippincott Williams & Wilkins].