Role of oxidative stress in concomitant occurrence of Fasciola gigantica and leiomyoma in cattle.

Fasciola gigantica is a parasitic helminth that predominantly infects the liver and bile ducts of cattle and causes great losses of cattle production in the southwestern regions of Iran. The purpose of the present study was to find out the possible relationship between the extent of liver destruction and oxidative stress by estimating the level of MDA, and SOD and GPX enzymes in the liver of cattle infected with F. gigantica. Studies were carried out on 49 infected and 20 healthy livers. Based on the results, the SOD activity of the infected livers was substantially lower than those of the healthy ones. As in the livers with more damage, a significant decrease was observed in the SOD activity. Although the GPX activity of the control livers and the livers with low damage showed no statistically significant variation this value was significantly different between the livers with high injury and the control ones. The MDA level of the infected animals was significantly higher than the non-infected animals. In addition, the level of MDA production showed a parallel correlation with the severity of infection. By histological examination, the lesions in infected livers were varied from tortuous, organized fibrotic areas in or around the hepatic lobules, cirrhosis, and chronic catarrhal cholangitis to fresh migratory tunnels filled with RBC and eosinophils. Multifocal and relatively homogenous populations of densely packed spindle cells with blunt-ended nuclei, arranged in broad interlacing fascicles were noted in samples of 10 infected livers. Based on the histological features by routine and special staining and the results of the immune labeling, the tumors were diagnosed as hepatic leiomyoma. To the best of our knowledge, this is the first report on the concomitant occurrence of Fasciola gigantica infection and leiomyoma in cattle. Therefore, there is considerable evidence indicating that the severity of hepatic damage in fasciolosis is causally associated with the extent of intrahepatic oxidative stress. Future research is necessary in order to clarify the complex host-parasite interactions and to better define the oncogenic implications of F. gigantica infection.