Intraspecific Variation of Biological Activities in Venoms from Wild and CaptiveBothrops jararaca

Abstract

The venom of Bothrops jararaca is composed of complex mixture of molecules, mainly lectins, metalloproteinases, serinoproteinases, desintegrins, phospholipases, and peptides. This composition may vary according to the snake's age, gender, and region of origin. The aim of the was to determine individual variation in Bothrops jararaca venom in the Botucatu region, Sao Paulo State, Brazil, by means of enzymatic, biochemical, and pharmacological characterization, utilizing in vitro tests and biological assays. The activities were compared with those of Brazilian Reference Venom (BRV). Protein concentration varied between adult and juvenile groups. The electrophoretic profiles were similar, with molecular masses ranging between 25 and 50 kD, but with intraspecific variations. Reverse-phase high-performance liquid chromatography (RP-HPLC) revealed protein concentration differences. Coagulant activity did not differ significantly among adult groups, but there was a large variation between juvenile venom and BRV, which coagulated more extensively. Venoms from adults displayed greater hemorrhagic activity, especially in males recently obtained from the wild. In contrast, juveniles kept in captivity and adult males showed higher values. Edematogenic activity displayed an increase in edema in all groups. At the mean lethal dose (LD₅₀), toxicity varied significantly between groups, with venom from captive females being threefold more toxic than juvenile venom. Data illustrate the intra- and interspecific complexity that occurs in snake venoms, which may be attributed to ontogenetic, sexual, and environmental factors that affect variability in Bothrops jararaca venom. Further, it is proposed that Brazilian public health authorities document the constitution of pooled venom employed in the immunization of serum-producing animals due to this variability in venom properties. Given the large Brazilian territory, this variability requires regional monitoring and evaluation of the efficacy of bothropic antivenom in treatment of snakebite and consequent permanent sequelae observed.

Venom complexity of Bothrops atrox (common lancehead) siblings

“…Differences in the composition and activity of snake venoms from the same species are a worldwide researchers concern. These differences can influence directly in the antivenom production and in the success of patient treatment [54][55][56][57].…”

From birth to adulthood: An analysis of the Brazilian lancehead (Bothrops moojeni) venom at different life stages

“…Whilst extensively studied, intraspecific variability still needs more elucidation, as it could have an impact in snakebite treatment [ 36 , 61 ]. In this work, we analyzed the venom of captive-born Brazilian lancehead at different life stages in controlled environment.…”

Evidence for Snake Venom Plasticity in a Long-Term Study with Individual Captive Bothrops atrox

“…In previous studies, we reported that pools of venoms from snakes collected from the floodplain habitat differed from the others on functional activities [50,51] and higher individual venom variability was observed among this group, suggesting that a higher variability may be a characteristic favored in snakes inhabiting this type of environment. The major venom-enzymatic activities varied in the nine specimens included in this group and these changes found no correlation to the predicted composition of the fractions whose peaks showed differences in height, suggesting that small fluctuations in the expression of different isoforms of these compounds, recorded due to the high sensitivity of the enzymatic assays, may contribute to this apparent functional variability of the venoms, as reported in other comparative studies using enzyme assays [40,44,52]. Nevertheless, it is important to note that the variability within this group of nine snakes was related to toxins present at low abundance in the venoms.…”

“…This hypothesis has been tested recently by different groups and the results are still inconclusive. Some evidence indicates little influence of captivity maintenance on venom composition [26,40,41,42,43], while others show evidence that the environmental changes due to introduction to captivity may modify venom composition [44]. However, these studies compare venoms from groups of snakes recently caught in the wild with groups of other specimens maintained for a long term under captivity.…”