6-O-PALMITOYL-L-ASCORBIC ACID (ASC16) AS INHIBITOR OF OPHIDIAN VENOM ENZYMES

SÁNCHEZ MASLOVSKI; FUSCO, L; LAURA C. LEIVA

Buenos Aires

Jornada; XXIII Annual meeting of the argentinean biology society; 2022

Instituto de Bilogía y Medicina experimental

Snake venoms are a complex mixture of toxins as Phospholipases A2 (PLA2) nature, serine protease, 5´ nucleotidases, metalloproteinases, phosphodiesterases, glutaminylcyclase, C-type lectin, crotamine, L-amino acid oxidase, disintegrins and others. There is currently a growing interest in the search for natural or synthetic inhibitors acting on the components of venom and allow mitigate the local and systemic effects of their components. In the present work, ASC16 was proposed as an inhibitor of the main toxic enzymes in the venom of C. d. terrificus and Bothrops diporus. For this, ASC16 (0,1 µg/µL) was incubated with entire venom (1 µg/µL) and substrate-specific kinetic assays were performed to measure the activity (µmol/min/mL) of PLA2, serine protease, phosphodiesterase and L-amino acid oxidase. In order to evaluate the metalloprotease activity, a proteolytic assay was performed with B. diporus venoms using azocasein as substrate. Results were expressed as mean ± SD independent experiments performed in duplicate. The in vitro experimental data were analyzed with the statistical package InfoStat version 2008. Statistical analyses were performed using the LSD Fisher test, being considered significant if p < 0.05. The results show that ASC16 inhibited PLA2 by 80.16% (2:1 w/w), serine protease 61.57% (1:10 w/w), phosphodiesterase 45.13% (1:20 w/w), L-amino acid oxidase 50.64% (1:20 w/w) and metalloproteinase 50% (1:10 w/w) activities. A decrease in the activity of the enzymes tested was observed due to a non-specific inhibition of ASC16 on the ophidian enzymes. Consistent with our study, similar research was carried out with venom from the species Echis carinatus that ASC16 significantly inhibits PLA2 activity and acts non-specifically with other enzymes. It is concluded that ASC16 has potential as an inhibitor by reducing the enzymatic activity of the main ophidian proteins. Future studies should be conducted to further investigate the mechanisms of ASC16 inhibition and it is safety.