Circulating markers of oxidative stress and liver fibrosis in Sudanese subjects at risk of schistosomiasis and hepatitis.

Epidemiological studies in the developing world are frequently biased by the simultaneous presence of several infectious pathogens. In the present study, we examined the usefulness of circulating markers of oxidative stress and liver fibrosis to investigate the distinct forms of chronic liver inflammations associated with schistosomiasis and viral hepatitis, respectively. The study was performed in a Sudanese population exposed to Schistosoma.

Arginase expression in peritoneal macrophages and increase in circulating polyamine levels in mice infected with Schistosoma mansoni.

We investigated the nitric oxide (NO) synthase and arginase pathways in resident peritoneal macrophages of mice infected with the tropical parasite Schistosoma mansoni. The two enzymes may have opposite effects, insofar as NO may be involved in the killing of the parasite whereas arginase may stimulate parasite growth via polyamine synthesis. We determined the effects of the infection on the expression and activity of the two enzymes in macrophages, before and after cytokine activation.

Anti-inflammatory properties of molecular hydrogen: investigation on parasite-induced liver inflammation.

Molecular hydrogen reacts with the hydroxyl radical, a highly cytotoxic species produced in inflamed tissues. It has been suggested therefore to use gaseous hydrogen in a new anti-inflammatory strategy. We tested this idea, with the aid of the equipment and skills of COMEX SA in Marseille, a group who experiments with oxygen-hydrogen breathing mixtures for professional deep-sea diving.

Inhibition of nitric oxide synthase activity reduces liver injury in murine schistosomiasis.

We investigated the involvement of nitric oxide in Schistosoma-induced liver injury. We found that inducible nitric oxide synthase mRNA became detectable in the liver at the onset of parasite egg laying and levels then increased as the eggs accumulated in the organ. Enzyme concentration and activity paralleled mRNA levels.

Hyaluronate levels and markers of oxidative stress in the serum of Sudanese subjects at risk of infection with Schistosoma mansoni.

We showed previously that infection by Schistosoma mansoni not only triggers the production of reactive oxygen species in mouse liver but also leads to the alteration of antioxidant defences. To determine whether such events occur in humans, we measured the serum markers of oxidative stress, i.e.

Visualization of oxygen radical production in mouse liver in response to infection with Schistosoma mansoni.

Background/aims: The tropical parasite S. mansoni induces granulomatous inflammation in the liver, following the lodging of eggs in this organ. In vitro studies suggested that the host's response might involve the production of oxygen radicals.

Development of eosinophil peroxidase activity and concomitant alteration of the antioxidant defenses in the liver of mice infected with Schistosoma mansoni.

Background/aims: The tropical parasite Schistosoma mansoni causes granulomatous inflammation following lodging of eggs in portal capillaries. In vitro studies indicated that the host reaction should involve reactive oxygen intermediates; however, it is not known what occurs in vivo at the site of the disease. Moreover, the ultimate pathophysiological effects of oxidative processes depend upon antioxidant factors, which are investigated in this study.