Full title: Inhibition of harmful effects from Bothrops alternatus venom by Casearia arborea extract

Abstract

This study aimed to assess the action of methanol extract from Casearia arborea (Salicaceae) branches against the harmful effects of Bothrops alternatus venom. The venom was tested combined or not with Casearia arborea methanol extract (CAME) at different ratios (1:10, 1:50 (w/w)). Coagulant activity was tested using bovine plasma at 37°C and crude venom (10µg). The hemorrhagic activity of the venom (15µg) was assessed 150 min after inoculating venom samples in the dorsal region of mice. Myotoxic activity was tested by injecting venom into the gastrocnemius muscle of mice, followed by determination of creatine kinase (CK) levels. Phospholipase A 2 activity was evaluated using egg yolk as substrate. Histologic sections of gastrocnemius muscles were analyzed under an optical microscope. The results indicated that CAME inhibited coagulant activity by 59% and reduced hemorrhagic activity by 91%. Myotoxicity analysis demonstrated that serum CK levels declined and phospholipase A 2 activity assessment showed a 50% reduction. The histological sections analyzed indicated decreased local tissue damage in the presence of CAME. These results suggest that CAME may be a potential adjuvant in conjunction with the serum therapy currently applied to neutralize botropic venoms.