Superoxide dismutase activity and lipid peroxidation in the liver of guinea pig infected with Leptospira interrogans.

Superoxide dismutase (SOD) activity and the degree of lipid peroxidation were studied over a two week period in guinea pigs infected with Leptospira interrogans derived from wild mice. The total SOD activity in infected host liver increased by four-fold two days after infection; this was followed by a 20% decrease resulting in levels comparable to normal, uninfected liver. During the period of decreasing SOD activity after day two, the levels of TBA-reactive material (TBARS) are increased by three-fold in infected guinea pig, liver, compared to uninfected liver. The results indicate that SOD attenuates intracellular superoxide-mediated toxic effects in guinea pigs infected with L. interrogans. In addition, electron microscopy structure demonstrates correlated pathogenic shrinkage of mitochondrial and Kupffer cell structures.