IN VITRO PREVENTION OF LIPID PEROXIDATION BY EXTRACTS OF BIOMPHALARIA GLABRATA

BILBAO, MARÍA GUILLERMINA; VERRENGIA GUERRERO, NR; COCHÓN, AC.

Iguazú

Congreso; SAIB; 2004

Sociedad Argentina de Investigación Bioquímica

The assessment of the total scavenger capacity of oxyradicals by a tissue provides a well understanding of its resistance to toxicity caused by reactive oxygen species. In this study, we evaluated the antioxidant capacity of extracts derived from the snail Biomplhalaria glabrata against in vitro hydroxyl radical- induced oxidative injury to lipids. Time course lipid peroxidation was assayed by the thiobarbituric acid test. Hydroxyl radicals were generated at 37°C by the iron plus ascorbate Fenton reaction. Homogenates of total soft tissue (TST) and of different anatomical regions of B. glabrata were made in phosphate saline buffer, pH 7.4 and centrifuged at 3000 x g for 15 min to precipitate insoluble pigments. No Fe++/ascorbate induced Iipoperoxidation could be observed in extracts of TST and hepatopancreas. Instead, a slight lipoperoxidation occurred when gonadal and pulmonary tissues were analyzed (0.4 and 0.6 fold of increase, respectively). Extracts of TST inhibited in a dose dependent mode the Fe++/ascorbate induced lipoperoxidation of pig Iiver homogenate (highest inhibition observed: 78%). Considering the different anatomical regions analyzed, the highest antioxidant capacity was found in hepatopancreas. TST from non-pigmented organisms showed a higher antioxidant capacity than TST from pigmented ones. Neither endogenous levels of GSH nor the protein fraction of snail extracts would account for the lipid peroxidation inhibition observed.