The Venom Cure
Cone Shell Cures

When it comes to research on venom and converting it into useful drugs, studies involving exotic snakes or brightly colored frogs seem to attract the most attention. However, one of the most promising new venom-derived drugs actually comes from a very modest-looking sea snail.

Worldwide, there are more than 600 kinds of cone shells found mostly in tropical waters around the Pacific. Collectors love them because their shells are decorated with an amazing array of intricate patterns.

Biologists, however, have long been fascinated by the behavior of these clever hunters. Some cone shells target other snails, while others like to feast on fish. To sense food, cone shells filter water through a tubelike organ called a siphon, awaiting a whiff of the telltale chemicals emitted by their prey.

 

  

To sense food, cone shells filter water through a tubelike organ called a siphon.

Then, when its victim comes near, the cone shell extends a proboscis armed with a harpoonlike tip that injects venom filled with special chemicals called “conotoxins.” These toxins stop nerve cells from communicating with each other, causing paralysis within seconds and, eventually, death. Cone shells have even killed people who pick them up, unaware of the danger. Indeed, cone snail venom is so powerful and painless that victims can die unaware that they’ve even been bitten.

Conotoxins have long interested medical researchers because of their potential painkilling abilities. It turns out, however, that cone shell venom is very complex; each kind contains perhaps 50 or more different chemicals that target the brain and nervous system. Overall, researchers believe that more than 50,000 conotoxins may exist. That diversity has made it hard for them to isolate a specific chemical to work on.

But over the last few decades, conotoxins have begun to give up their secrets. Researchers have published more than 2,500 papers on the chemicals, and have described and identified more than 100 specific toxins which show promise for treating everything from arthritis to cancer. But the first new drug derived from a conotoxin, approved in 2004, targets chronic pain. Researchers estimate that the drug, based on the venom from the delicate gray and ivory magician cone shell, is a thousand times stronger than morphine, the most powerful traditional painkiller.

Even as cone shells show promise for medicine, however, their survival may be at stake. Collectors gather millions of the animals each year for the decorative shell trade. Demand from conotoxin researchers is growing too, since many shells may be needed to produce even small amounts of toxin. And coral reefs, which support more than half of all cone shell species, are under increasing threat from human activities.

To protect cone shells, biologists are asking nations in tropical zones to take new steps to monitor the shell trade and protect reefs. “To lose these species would be a self-destructive act of unparalleled folly,” researcher Eric Chivian of Harvard University in Cambridge, Massachusetts wrote in a 2003 paper published by the journal SCIENCE. “Tropical cone snails may contain the largest and most clinically important pharmacopoeia of any [group of animals] in nature.”

  • Carol Simpson

    I recently read that the formula for the cone shellvenom (the pain killer)had been sold to a firm in England. Do you know the name of the drug and the company that sells it? I’ve studied this for a long time (I’m a conchologist) but have only seen it recently on the Discovery Health channelon tv.

  • Lee Rubin

    As a veterinarian , I think cone shell venom derived anodyne could be a useful drug . Is it available commercially ?

  • L.Gikbson

    For poster #1: I believe you are referring to the drug Prialt (Ziconotide) produced by Elan.

  • Z. Bayer

    For poster 2, we do not have it available in large enough quantities, nor have they been tested enough.

  • pramod kc

    i came to learn that biting of coneshells are painfull.
    is it true
    i m the student of b.pharm

  • James Platter

    While in the Navy, I was stationed in Guam. While there, I logged 137.30 minutes Underwater. I also loved collecting shells. However, I had a simple golden rule–I only took shells where the host, the origanal owner was already dead and gone. I am gulty of having taken some shells that were occupied by hermite crabs. If only every body would follow that practice there would be a lot more cone shells living on the reefs and of every other speicies for that matter.

  • http://aquamagnets.com/cart/ aquamagnets.com

    Heya i am for the primary time here. I came across this board and I find It really helpful & it helped me out much. I am hoping to give something back and aid others like you aided me.

  • Matt Holly

    Does anyone purchase live cone shells for this medical study market?? They are a great predatoid in aquaculture work…defenders of the clam and oyster spat. Living UW in the marshall islands, look me up!!

  • Tami

    i have been stung by many cone snails in our aquarium gravel. I couldnt hardly breathe the last time i was cleaning the gravel in our aquarium, as it was almost completlysnails. The fish couldnt eat. The snails were taking over. so i was always picking and scooping them out.I didn”t realize i was being stung at first. We were breeding Albino bristlenose plecostomuses , and had about 150 babies and three adults. When i would drop in algae wafers, the snails just covered the gravel completely in mounds. They were small, light brown and shaped like a waffle cone. No one told us they could stab you with a neurotoxin at the pet shop. They still dont believe me at Petworld when i told them. They populated so fast. so i was picking them outall the time, and each time i would feel worse after cleaning the aquarium., and lost my hearing. i only have partial hearing back. no one believes me… no one can help with solutions for my head pain and ringing in my ears.it feels like im under water or something. Mt ears hurt so bad. My breathing returned to normal the next few days. Its been a month and my hearing hasnt come back but only partially. Will i get my hearing back? Tami

  • Loni

    oh WOW Tami – speaking to you as a nurse, I can only guess at what may be going on there with you! I didn’t even know these little suckers were being sold at stores! I guess ppl may believe that they are too tiny to cause a problem; but that premise could perhaps be faulty reasoning. One bee sting can cause a person to go into a slight anaphylactic shock response, and a few benedryl pills (or a benedryl injection) usually takes care of that no problem; but if that same person that obviously has a problem with one bee sting, gets stung by a whole bunch of them at one time – they may die from it – and FAST! There are ppl that are SO sensitive to bee venom that even ONE STING is very dangerous to them! So – in that train of thought, you may be sensitive to whatever it is in these little suckers; and dealing with ALOT of “little” stings may truly be causing you a problem! If I were in your shoes I would do 2 things:

    I would start looking for a neurologist that has knowledge in the field of neurotoxins – and I would contact a researcher that deals with neurotoxins. If you find a researcher that does this, then he or she may know a Neurologist that you can refer to – who will at least consult with a neurologist in your area. That said, finding a local Neurologist in your area, that is actually open mined enough to be on board with you on this issue – may be VERY hard to find!! I would perhaps look for a D.O. versus an M.D. just because medical doctors that are osteopathically trained are usually more open to alternative treatments and what not. That said, I HAVE worked with a few rare and special M.D.s that are VERY open minded and will look into all aspects of diverse treatments for their patients. Its just a matter of finding that special physician in your area that is right for YOU – whether they are an M.D. or a D.O. medical doctor…

    I can say that one Neurotoxin researcher that I personally think is BRILLIANT is a woman by the name of Angel Yanagihara at the University Hawaii Manoa (UH Manoa). Just do a google search for her and go to the University site – you may be able to contact her personally or through the university’s email; and she may be able to give you some info or direct you to a Neurologist that may just know something about this issue. I would contact her for SURE! And it wouldn’t hurt to also contact the Miami Serpentarium Laboratories in Punta Gorda Florida. They may know of particular doctors in the U.S. that are savvy with neurotoxins and their prolonged effects and treatments. Bill Haast, its founder, was a pioneer in neurotoxin research – and some ppl say he was alittle crazy too bc he actually injected himself with snake venom! BUT – he was also one of the first ppl to see the scientific benefits in venoms – so as far as neurotoxin scientists are concerned – he was a rock star!! LOL ! Hey – credit is given where credit is due huh?

    Tami, I hope this response finds you… and in some way helps…

    One things for sure! Get rid of that snail infested aquarium gravel!!

    Hugs…

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