0000000000640139
AUTHOR
William H. Bannister
The role of glutathione in protection against DNA damage induced by rifamycin SV and copper(II) ions.
Incubation of calf thymus DNA in the presence of rifamycin SV induces a decrease in the absorbance of DNA at 260 nm. The effect, was found to be proportional to the antibiotic concentration and enhanced by copper(II) ions. In the presence of rifamycin SV and copper(II), a significant increase in thiobarbituric acid-reactive (TBA-reactive) material is also observed. This effect is inhibited to different degrees by the following antioxidants: catalase 77%; thiourea 72%; glutathione (GSH) 62%; ethanol 52%; and DMSO 34%, suggesting that both hydrogen peroxide (H2O2) and hydroxyl radicals (OH.) are involved in DNA damage. Rifamycin SV-copper(II) mixtures were also found to induce the production …
Effect of metal ion catalyzed oxidation of rifamycin SV on cell viability and metabolic performance of isolated rat hepatocytes.
The effect of rifamycin SV on metabolic performance and cell viability was studied using isolated hepatocytes from fed, starved and glutathione (GSH) depleted rats. The relationships between GSH depletion, nutritional status of the cells, glucose metabolism, lactate dehydrogenase (LDH) leakage and malondialdehyde (MDA) production in the presence of rifamycin SV and transition metal ions was investigated. Glucose metabolism was impaired in isolated hepatocytes from both fed and starved animals, the effect is dependent on the rifamycin SV concentration and is enhanced by copper (II). Oxygen consumption by isolated hepatocytes from starved rats was also increased by copper (II) and a partial i…