Pharmacological characterization of venoms from three theraphosid spiders: Poecilotheria regalis, Ceratogyrus darlingi and Brachypelma epicureanum

Abstract

BackgroundTarantulas (Theraphosidae) represent an important source of novel biologically active compounds that target a variety of ion channels and cell receptors in both insects and mammals. In this study, we evaluate and compare the pharmacological activity of venoms from three taxonomically different theraphosid spiders bred in captivity: Poecilotheria regalis, an aggressive arboreal tarantula from southeastern India; Ceratogyrus darlingi, an aggressive tarantula from southern Africa; and Brachypelma epicureanum, a docile tarantula from the Yucatan dry forest of Mexico. Prior to this study, no research had been conducted with regard to the composition and pharmacological activity of these venoms.MethodsThe pharmacological characterization of the venoms was described for the first time by the assessment of their toxicity in crickets (LD50) along with their nociceptive (by using the formalin test), hyaluronidase, phospholipase A2, edematogenic and caseinolytic activity.ResultsP. regalis and B. epicureanum venoms induced a similar lethal effect on crickets (LD50 = 5.23 ± 3.1 and 14.4 ± 5.0 μg protein/g 48 h post-injection, respectively), whereas C. darlingi venom (119.4 ± 29.5 μg protein/g 48 h post-injection) was significantly less lethal than the other two venoms. All three venoms induced similar edematogenic activity on rats but did not induce nociceptive behavior. The assessment of enzymatic activity indicated that P. regalis venom induces significantly higher hyaluronidase activity (27.6 ± 0.9 TRU/mg) than both C. darlingi (99.7 ± 1.9 TRU/mg) and B. epicureanum (99.6 ± 1.6 TRU/mg); these latter venoms did not display phospholipase A2 or caseinolytic activity.ConclusionsThis study demonstrates that these theraphosid spiders of different habitats produce venoms with different activities. P. regalis venom displays a high level of hyaluronidase activity, which may be associated with its potentially medically significant bite.

Composition and biological activities of the aqueous extracts of three scleractinian corals from the Mexican Caribbean: Pseudodiploria strigosa, Porites astreoides and Siderastrea siderea

“…In the current study, we found that the extracts from the three scleractinian corals were lethal to crickets, with LD 50 values similar to those found for M. complanata extract. Moreover, the LD 50 values found for these cnidarians are quite similar to those presented by theraphosid spiders [27]. …”

Non-clinical evidence supports anti-inflammatories as more effective medication than antihistamines against tarantula local effects envenomation

“…Comparable paw oedema was observed with B. epicureanum but no pathways or toxins were investigated [27]. These results are evidences of the presence of peptides that may elicit inflammation in this venom.…”

Aspartic Acid Isomerization Characterized by High Definition Mass Spectrometry Significantly Alters the Bioactivity of a Novel Toxin from Poecilotheria

“…For the purpose of this study, we employed a comprehensive high definition mass spectrometry (HDMS E ) approach to investigate the venom from ten species of an arboreal tarantula commonly known as the "tiger" or "ornamental" spider (Genus Poecilotheria): P. striata, P. regalis, P. rufilata, P. formosa, P. metallica, P. miranda, P. tigrinawesseli, P. fasciata, P. ornata, P. smithi, and P. vittata. While there have been studies of whole venom from this genus of aggressive tarantula [46][47][48][49], our laboratory is the first to characterize a complete primary structure of a poecilotheriatoxin as well as evaluate the impact isomerization has on a toxin's physiological effect(s). Using a combination of digestion strategies, fragmentation techniques, and tandem high-resolution ion mobility spectrometry (IMS-interchangeable in this manuscript as high definition mass spectrometry HDMS E ), potential candidates for one non-enzymatic PTM was identified and confirmed, i.e., isomerization of Asp.…”