justGreg
03.09.2008, 22:40
"Toxic activities of Brazilian centipede venoms" by:
Mar?´lia B. Malta a, Marcela S. Lira a, Sabrina L. Soares a, Guilherme C. Rocha a, Irene Knysak b,
Rosana Martins b, Samuel P.G. Guizze b, Marcelo L. Santoro c, Katia C. Barbaro a,*
a b s t r a c t
Centipedes have a venom gland connected to a pair of forceps, which are used to arrest
preys. Human victims bitten by centipedes usually manifest burning pain, paresthesia
and edema, which may develop into superficial necrosis. The aim of this work was to
characterize and compare toxic activities found in venoms of three species of Brazilian
centipedesdOtostigmus pradoi, Cryptops iheringi and Scolopendra viridicornis. By SDS–
PAGE (4–20%), important differences were noticed among venoms (between 7 and
205 kDa). Few bands showed feeble caseinolytic, fibrinogenolytic and gelatinolytic activities
by zymography, but strong hyaluronidase activity was observed in S. viridicornis and
O. pradoi venoms. In addition, such activities could be inhibited by o-phenanthroline, indicating
that these enzymes are metalloproteinases. All venoms induced nociception,
edema and myotoxicity in mice, but only S. viridicornis induced mild hemorrhagic activity.
No coagulant activity was detected in centipede venoms. Low phospholipase A2 activity
was observed exclusively in S. viridicornis and O. pradoi venoms, but these venoms had intense
direct hemolytic activity on human erythrocytes. Cross-reactivity among venoms
was observed using species-specific sera raised in rabbits. Differences were noticed among
centipede venoms, but S. viridicornis is indeed the most toxic venom and thereby it could
induce a more severe envenomation.
Enjoy!
Greg
Mar?´lia B. Malta a, Marcela S. Lira a, Sabrina L. Soares a, Guilherme C. Rocha a, Irene Knysak b,
Rosana Martins b, Samuel P.G. Guizze b, Marcelo L. Santoro c, Katia C. Barbaro a,*
a b s t r a c t
Centipedes have a venom gland connected to a pair of forceps, which are used to arrest
preys. Human victims bitten by centipedes usually manifest burning pain, paresthesia
and edema, which may develop into superficial necrosis. The aim of this work was to
characterize and compare toxic activities found in venoms of three species of Brazilian
centipedesdOtostigmus pradoi, Cryptops iheringi and Scolopendra viridicornis. By SDS–
PAGE (4–20%), important differences were noticed among venoms (between 7 and
205 kDa). Few bands showed feeble caseinolytic, fibrinogenolytic and gelatinolytic activities
by zymography, but strong hyaluronidase activity was observed in S. viridicornis and
O. pradoi venoms. In addition, such activities could be inhibited by o-phenanthroline, indicating
that these enzymes are metalloproteinases. All venoms induced nociception,
edema and myotoxicity in mice, but only S. viridicornis induced mild hemorrhagic activity.
No coagulant activity was detected in centipede venoms. Low phospholipase A2 activity
was observed exclusively in S. viridicornis and O. pradoi venoms, but these venoms had intense
direct hemolytic activity on human erythrocytes. Cross-reactivity among venoms
was observed using species-specific sera raised in rabbits. Differences were noticed among
centipede venoms, but S. viridicornis is indeed the most toxic venom and thereby it could
induce a more severe envenomation.
Enjoy!
Greg