Anthelminthic Activity of Assassin Bug Venom against the Blood Fluke Schistosoma mansoni

Abstract

Helminths such as the blood fluke Schistosoma mansoni represent a major global health challenge due to limited availability of drugs. Most anthelminthic drug candidates are derived from plants, whereas insect-derived compounds have received little attention. This includes venom from assassin bugs, which contains numerous bioactive compounds. Here, we investigated whether venom from the European predatory assassin bug Rhynocoris iracundus has antischistosomal activity. Venom concentrations of 10–50 µg/mL inhibited the motility and pairing of S. mansoni adult worms in vitro and their capacity to produce eggs. We used EdU-proliferation assays to measure the effect of venom against parasite stem cells, which are essential for survival and reproduction. We found that venom depleted proliferating stem cells in different tissues of the male parasite, including neoblasts in the parenchyma and gonadal stem cells. Certain insect venoms are known to lyse eukaryotic cells, thus limiting their therapeutic potential. We therefore carried out hemolytic activity assays using porcine red blood cells, revealing that the venom had no significant effect at a concentration of 43 µg/mL. The observed anthelminthic activity and absence of hemolytic side effects suggest that the components of R. iracundus venom should be investigated in more detail as potential antischistosomal leads.

Alterations in the tegument surface of adult fluke, Fasciola gigantica, after in vitro treatment with the crude venom of the oriental hornet, Vespa orientalis

“…They observed that it had remarkable pleiotropic effects on the physiological, cellular, and molecular processes in adult male and female Schistosoma mansoni. Tonk et al (2020) investigated the antischistosomal activity of the venom from the European predatory assassin bug, Rhynocoris iracundus. The components of wasp venom are commonly categorized as (i) bioactive molecules such as serotonin, histamine, catecholamines, tyramine, acetylcholine, avonoids, and biologically active amines, (ii) high molecular weight proteins such as hyaluronidases, phospholipases, and antigen 5, and (iii) low molecular weight peptides such as mastoparan (Nakajima 1986).…”

Hexapod Assassins’ Potion: Venom Composition and Bioactivity from the Eurasian Assassin Bug Rhynocoris iracundus

“…We used the recently established method to stimulate R. iracundus nymphs to display a defense posture and subsequently collected the venom as illustrated in Figure 2 [30]. This procedure performed with one individual assassin bug refers to one venom harvesting event.…”

“…In our previous study we already discovered that R. iracundus venom causes onlỹ 6% of hemolysis on porcine erythrocytes [30] and erythrocytes from different vertebrate species show different levels of hemolysis [57]. This suggests that assassin bug venom has selectivity on different erythrocyte types making assassin bug venom interesting for leukemia studies.…”

Heilen mit Tiergiften

“…Wenngleich Venomics noch eine sehr junge Disziplin darstellt, konnten hier in der jüngeren Vergangenheit große Fortschritte erzielt werden. Während noch bis vor kurzem so gut wie nichts über die kleineren Gifttiere bekannt war, so wachsen unsere Kenntnisse über die Gifte von Raub fliegen, Raubwanzen, Wespen, Würmern und kleinen Spin nen wie der Wespenspinne stetig [20][21][22][23][24]. Aktuell laufende Forschungen zu den Giften von Bienen, Ameisen, weiteren Spinnen und einigen Fischen werden in Kürze abgeschlos sen sein.…”