Serum and liver enzymes of collagen synthesis in hepatic murine schistosomiasis mansoni.

Serum galactosylhydroxylysyl glucosyltransferase (S-GGT), liver galactosylhydroxylysyl glucosyltransferase (L-GGT), liver hydroxylysyl galactosyltransferase (L-GGal-T) and liver prolyl hydroxylase (L-PH) activities were measured in CF1 female mice each week for 10 weeks after infection with Schistosoma mansoni (50 cercariae per mouse). None of the enzyme activities measured were significantly increased in the first six weeks following the infection. However, the activities increased thereafter reaching a maximum of seven-fold for S-GGT, five-fold for L-GGT, three-fold for L-GGal-T and ten-fold for L-PH compared with control animals. The increase in S-GGT activity was positively correlated with L-GGT (r = 0.788), L-GGal-T (r = 0.774) and L-PH (r = 0.800). The present data suggest that during the first six weeks of the development of murine hepatic schistosomiasis mansoni infection, few eggs bombard the liver. The biochemical changes during this period are mild. During weeks 7 to 10, which is the active fibrotic stage, the liver biochemical markers of collagen synthesis increase rapidly and lead to fibrotic morphological features that are the chronic irreversible hepatic changes characteristic of this infection. The data reported here indicate that the aggressive fibrotic changes in liver during weeks 7 to 10 of murine schistosomiasis infection are predicted by S-GGT activity.