Peptide-rich venom from the spider Heteropoda venatoria potently inhibits insect voltage-gated sodium channels

Toxicon. 2017 Jan:125:44-49. doi: 10.1016/j.toxicon.2016.11.252. Epub 2016 Nov 17.

Abstract

Heteropoda venatoria is a venomous spider species distributed worldwide and has a characteristic habit of feeding on insects. Reverse-phase high-performance liquid chromatography and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry analyses revealed that H. venatoria venom contains hundreds of peptides with a predominant molecular weights of 3000-5000 Da. Intra-abdominal injection of the venom had severe toxic effects on cockroaches and caused death at higher concentrations. The LD50 was 28.18 μg/g of body weight in the cockroach. It was found that the venom had potent inhibitory effect on voltage-gated sodium channels (VGSCs) in Periplaneta americana cockroach dorsal unpaired median (DUM) neurons with an IC50 values of 6.25 ± 0.02 μg/mL. However, 100 μg/mL venom only partially blocked VGSC currents in rat dorsal root ganglion cells, a much lower inhibitory effect than that on DUM VGSCs. Our results indicate that the venom of H. venatoria contains diverse neurotoxins that might become new leads for bioinsecticides.

Keywords: Dorsal unpaired median neurons; H. venatoria venom; Insecticides; Voltage-gated sodium channels.

MeSH terms

  • Animals
  • Arthropod Proteins / chemistry
  • Arthropod Proteins / pharmacology*
  • Chromatography, High Pressure Liquid
  • Cockroaches / drug effects
  • Insect Proteins / antagonists & inhibitors*
  • Lethal Dose 50
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Spider Venoms / chemistry
  • Spider Venoms / pharmacology*
  • Spiders*
  • Voltage-Gated Sodium Channel Blockers / chemistry
  • Voltage-Gated Sodium Channel Blockers / pharmacology*

Substances

  • Arthropod Proteins
  • Insect Proteins
  • Spider Venoms
  • Voltage-Gated Sodium Channel Blockers