jellyfish – GOLLYGEE!

A jellyfish. Image from blogs@ Cape Breton University

Looks like scientists may have stumbled upon a new cure for jellyfish stings. Scientists at the University of Hawaii found zinc gluconate inhibits the action of jellyfish venom. From Scientific American:

Yanagihara used electron microscopy to visualize the venom’s affects on blood cells, and as suspected, found that venom porins create holes that lead to cell rupture. But as previous clinical research had shown, the cells bursting wasn’t the real issue; Yanagihara found that instead, for several minutes before they break apart, red blood cells leaked potassium. Animal models confirmed that this sudden spike of potassium in the blood stream, termed hyperkalemia, is what leads to rapid changes in heart rate and function and, ultimately, the cardiovascular collapse that causes death by jellyfish. With the physiology of stings revealed, Yanagihara could finally start the laborious task of finding a way to stop the venom in its tracks.

Jellies aren’t the only animals that create porins. “The structural motif of the cubozoan porin reminded me of the bacterial porins,” said Yanagihara. “I scoured that literature to look for inhibitors of the self assembly of those pore forming toxins and discovered studies from the 1940s even as far back as the 1890′s citing zinc ion as useful in the inhibition of bacterial driven lytic reactions.” Yanagihara tested over 100 compounds to see if they inhibited jellyfish venom, and found that one of the safest—zinc gluconate—worked well.

Scientists aren’t 100% sure how zinc compounds inhibit the porins, but they believe that the zinc disrupts the binding domains necessary for the proteins to assemble to form pores. In in vitro models, Yanagihara found that a low dose of zinc gluconate completely prevented the venom’s blood cell busting effect. She then tested the compound in animal models, and found it worked better than the commercially available antivenom for box jelly stings, keeping the mice alive more than twice as long as the antivenom.

Turritopsis dohrnii, the immortal jellyfish.

he New York Times has an interesting (and long!) piece about a jellyfish species that appears to live forever. An excerpt:

Sommer was conducting research on hydrozoans, small invertebrates that, depending on their stage in the life cycle, resemble either a jellyfish or a soft coral. Every morning, Sommer went snorkeling in the turquoise water off the cliffs of Portofino. He scanned the ocean floor for hydrozoans, gathering them with plankton nets. Among the hundreds of organisms he collected was a tiny, relatively obscure species known to biologists as Turritopsis dohrnii. Today it is more commonly known as the immortal jellyfish.

Sommer kept his hydrozoans in petri dishes and observed their reproduction habits. After several days he noticed that his Turritopsis dohrnii was behaving in a very peculiar manner, for which he could hypothesize no earthly explanation. Plainly speaking, it refused to die. It appeared to age in reverse, growing younger and younger until it reached its earliest stage of development, at which point it began its life cycle anew.

Sommer was baffled by this development but didn’t immediately grasp its significance. (It was nearly a decade before the word “immortal” was first used to describe the species.) But several biologists in Genoa, fascinated by Sommer’s finding, continued to study the species, and in 1996 they published a paper called “Reversing the Life Cycle.” The scientists described how the species — at any stage of its development — could transform itself back to a polyp, the organism’s earliest stage of life, “thus escaping death and achieving potential immortality.” This finding appeared to debunk the most fundamental law of the natural world — you are born, and then you die.

Read the whole thing. It’s really worth it.

GOLLYGEE!

Tag: jellyfish

zinc cures jellyfish stings

the immortal jelly fish