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

• Published in: Journal of Venomous Animals and Toxins including Tropical Diseases
• Main Authors: Alejandro García-Arredondo, Luis Rodríguez-Rios, Luis Fernando Díaz-Peña, Ricardo Vega-Ángeles
• Format: Article in Journal/Newspaper
• Language: English
• Published: SciELO 2015
• Subjects: Poecilotheria regalis; Ceratogyrus darlingi; Brachypelma epicureanum; Tarantula; Venom; Toxicity; Arctic medicine. Tropical medicine; RC955-962; Toxicology. Poisons; RA1190-1270; Zoology; QL1-991; Arctic
• Online Access: https://doi.org/10.1186/s40409-015-0017-8; https://doaj.org/article/cc439d6389a446fc81f6f8c9a7667af0

Abstract Background Tarantulas (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. Methods The pharmacological characterization of the venoms was described for the first time by the assessment of their toxicity in crickets (LD 50 ) along with their nociceptive (by using the formalin test), hyaluronidase, phospholipase A 2 , edematogenic and caseinolytic activity. Results P. regalis and B. epicureanum venoms induced a similar lethal effect on crickets (LD 50 = 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 A 2 or caseinolytic activity. Conclusions This 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.