Abstract
Scorpion stings are the main cause of human envenomation in Brazil and, for the treatment of victims, the World Health Organization (WHO) recommends the use of antivenoms. The first step to achieve effective antivenom is to use a good quality venom pool and to evaluate it, with LD50 determination as the most accepted procedure. It is, however, time-consuming and requires advanced technical training. Further, there are significant ethical concerns regarding the number of animals required for testing. Hence, we investigated the correspondence between LD50 results, in vitro assays, and a strong correlation with proteolytic activity levels was observed, showing, remarkably, that proteases are potential toxicity markers for Tityus serrulatus venom. The comparison of reversed-phase chromatographic profiles also has a potential application in venoms’ quality control, as there were fewer neurotoxins detected in the venom with high LD50 value. These results were confirmed by mass spectrometry analysis. Therefore, these methods could precede the LD50 assay to evaluate the venom excellence by discriminating—and discarding—poor-quality batches, and, consequently, with a positive impact on the number of animals used. Notably, proposed assays are fast and inexpensive, being technically and economically feasible in Tityus serrulatus venom quality control to produce effective antivenoms.
Highlights
A high incidence of envenomation accidents caused by animals is recorded every year in Brazil.According to Brazil’s Ministry of Health, venomous animals were responsible for more than 161,000 accidents and 244 human deaths in 2013
Based on the current scenario, we evaluated the biochemical tests already proposed by the World Health Organization (WHO) and analyzed the applicability of three in vitro methods—tests of proteolytic and hyaluronidase activities, and the comparison of RP-HPLC profiles—as a quality control for Tityus serrulatus venom, which could precede the LD50 assay, discriminating venom batches with unsatisfactory quality and, reducing the number of animals required for this purpose
LD50 results were normalized by the inverse of the data (LD50 −1 ) and, subsequently, a linear dependence between LD50 and in vitro assays was analyzed using the Pearson Coefficient Test (Figure 5)
Summary
A high incidence of envenomation accidents caused by animals is recorded every year in Brazil.According to Brazil’s Ministry of Health, venomous animals were responsible for more than 161,000 accidents and 244 human deaths in 2013. A high incidence of envenomation accidents caused by animals is recorded every year in Brazil. The main factors driving this increasing incidence are linked to the biology of scorpions, associated with the parthenogenetic reproduction of the Brazilian yellow scorpion (Tityus serrulatus) and with its easy adaptation to urban environments [2]. These characteristics, along with the potent venom properties which contributes to the occurrence of critical clinical incidents, make the Tityus serrulatus scorpion one of the most significant species in terms of epidemiological and medical relevance in Brazil [3]. It is acknowledged that scorpion venom toxins mainly affect the autonomic nervous system, and, neurotoxins are the most studied molecules of scorpion venoms [4,5]. Recently have other non-neurotoxic molecules, like peptides and enzymatic components—mainly metalloproteases and hyaluronidase—been more extensively studied [6,7,8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
