Pharmacology of spider toxins

Spider venom is an intricate combination of target specific enzymatic and non-enzymatic toxins. In addition, the venom also contains polyamine neurotoxins, ATP, AMP, ADP, guanosine, 2,4,6-trihydroxy purine, gamma-aminobutyric acid, glutamic acid, aspartic acid, taurine, histamine, serotonin, tyramine, octomine, nor-adrenaline and inorganic salts. Several enzymes such as hyaluronidase, protease, phospholipase D, sphingomyelinase and neurotoxic peptides have been extensively characterized from spider venoms. Spider bite is an accidental event; envenomation can cause both local (edema, hemorrhage, myo/dermonecrosis) and systemic toxicity (neurotoxicity, myotoxicity, cytotoxicity and hemostatic alterations). While, the latter is pertaining to the very few groups of spiders, namely, Loxosceles species and Hippasa partita. The local and systemic toxicity may be attributed to the synergistic effect of both enzymatic and non-enzymatic toxins. More importantly, spider venom components possess immense potential for biotechnological and therapeutic applications. In addition, they have also been used as prototypes in drug design. Based on these facts, this review makes an attempt to provide an insight into the pharmacology of enzymatic toxins (Sphingomyelinase, Hyaluronidase, Phospholipase, Protease, Collagenase, Phosphodiesterase, ATPases, Alkaline phosphatase and Peptide isomerases) and non-enzymatic toxins (translationally controlled tumor proteins and serine protease inhibitors).