Preferential formation and decreased removal of cisplatin-DNA adducts in Chinese hamster ovary cell mitochondrial DNA as compared to nuclear DNA.

Levels of DNA adducts in Chinese hamster ovary (CHO) cells exposed to cis-diamminedichloroplatinum(II) (cisplatin) for 24 h, have been shown to be 4- to 6-fold higher in mitochondrial (mt) DNA as compared to nuclear (n) DNA (Olivero et al., Mutation Res., 346 (1995) 221).

The effect of L-carnitine on the AZT-induced destruction of human myotubes. Part II: Treatment with L-carnitine improves the AZT-induced changes and prevents further destruction.

Background: Zidovudine (AZT) as used in the treatment of AIDS causes a mitochondrial myopathy characterized by enzymatic defects in the respiratory chain system, accumulation of lipid droplets, and carnitine deficiency. Human myotubes treated with AZT demonstrate abnormal mitochondria, accumulation of lipid, and increased lysosomes. Because L-carnitine plays a major role in the transport of long chain fatty acids across the inner mitochondrial membrane and facilitates the beta-oxidation of fatty acids, we examined whether L-carnitine can enhance the recovery of the affected myotubes after withdrawal of AZT and can improve the structural changes of the myotubes while AZT treatment continues.

Effect of L-carnitine on the zidovudine-induced destruction of human myotubes. Part I: L-carnitine prevents the myotoxicity of AZT in vitro.

Background: Zidovudine (AZT) as used in the treatment of AIDS, causes a mitochondrial myopathy characterized by depletion of mitochondrial DNA, enzymatic defects in the respiratory chain system, and accumulation of lipid droplets. Most of these changes are also seen in normal human myotubes treated with AZT. Because L-carnitine plays a major role in the transport of long chain fatty acids across the inner mitochondrial membrane and facilitates the beta-oxidation of fatty acids, we examined the effect of L-carnitine in preventing the destructive effect of AZT on the mitochondria and the myotubes of human muscle in tissue culture.