Effects on cell cycle progression and cytoskeleton organization of five Bothrops spp. venoms in cell culture-based assays.

Snake envenomation is a neglected tropical disease. In Brazil, the genus is responsible for about 86% of snakebite accidents. Despite extensive evidence of the cytotoxicity of snake venoms, the cellular and molecular mechanisms involved are not fully understood, especially regarding the effects on cell cycle progression and cytoskeleton organization. Traditionally, the effectiveness and quality control tests of venoms and antivenoms are assessed by assays. Despite this, there is a rising effort to develop surrogate models according to the 3R principle (Replacement, Reduction, and Refinement). In this study, we treated rat liver cells (BRL-3A) with venoms from five species (, and ) and analyzed cell viability and IC by MTT assay, cell cycle phases distribution by flow cytometry, and morphology and cytoskeleton alterations by immunofluorescence. In addition, we evaluated the correlation between IC and the enzymatic and biological activities of each venom. Our results indicated that spp. venoms decreased the cell viability of rat liver BRL-3A cells. The rank order of potency was  >  >  > . The mechanisms of cytotoxicity were related to microtubules and actin network disruption, but not to cell cycle arrest. No clear correlation was found between the IC and retrieved literature data of enzymatic and biological activities. This work contributed to understanding cellular and molecular mechanisms underlying the spp. venom cytotoxicity, which can help to improve envenomation treatment, as well as disclose potential therapeutic properties of snake venoms.