Marine Snail's Toxin More Powerful Than Morphine
By Nic Rowan
Originally published by Reuters Health, July 12, 2002
MELBOURNE (Reuters Health) — Australian researchers have isolated a toxin from the cone shell, a type of a marine snail, that is not only a powerful analgesic but also accelerates recovery from nerve injury.
Although other pain-killing compounds have been isolated from the venom of the deadly creature, the newly discovered compound, known as ACV1, does not appear to affect blood pressure, according to Dr. Zeinab Khalil, deputy director of the National Aging Research Institute at the University of Melbourne.
Khalil and colleagues have isolated and patented the compound and also tested it on rats. They hope to move to human tests when negotiations with a commercial partner have been finalized.
"We are confident of the ability of the drug not only to inhibit pain but also to accelerate recovery of injured nerves, which is a unique property not previously documented for other analgesics," she told Reuters Health.
Eight weeks after inducing nerve damage in rats, there was only a 47% functional activity in animals given an inactive placebo, compared with a 83% functional activity in animals that received ACV1 treatment for a week, according to Khalil.
ACV1 is 10 times more potent than another conotoxin that has already been tested in humans and that compound is 1000 times more potent than morphine when it comes to inhibiting the function of sensory nerves involved in pain transmission, Khalil explained.
Khalil said that potential applications for the compound include treatment of any type of pain with a neuronal component, such as cancer pain, low back pain or pain due to arthritis, sports injury or shingles. Shingles is a reactivation of chickenpox virus, usually later in life, that results in an extremely painful, blistering rash.
No adverse behavioral or motor effects have been found in rats during the 12-week studies, and ACV1 does not affect systemic blood pressure, Khalil said.
Cone shells are found on reefs throughout the world and can deliver a painful and potentially life-threatening sting.
The research is being presented this week at the International Society for Toxicology Congress in Cairns, Australia.
