Therapeutic Spider Venom Photo Album
Scientists in Australia, home to some of the most poisonous creatures on Earth, have made an important discovery about spider venom that eventually could lead to a new class of painkillers.
Spiders use their venom to immobilize or kill their prey. Researchers from the University of Queensland isolated seven peptides—the building blocks of proteins—in spider venom that blocked the molecular pathway responsible for sending pain signals from the nerves to the brain. One peptide in particular, from a Borneo orange-fringed tarantula, had the right structure, stability and potency to potentially become a painkilling drug, the researchers said. The study was recently published in the British Journal of Pharmacology.
The medical community is eager to identify new medications to treat chronic pain, which affects about 15% of all adults, according to a 2012 study published in the Journal of Pain. Traditional painkillers such as morphine and widely used medications like hydrocodone can be addictive, and abuse of the drugs has soared in recent years, prompting stricter regulations from the U.S. Drug Enforcement Administration.
“Spider venom acts in a different way to standard painkillers,” said Jennifer Smith, a research officer at the University of Queensland’s Institute for Molecular Bioscience. Dr. Smith, one of the authors of the Australian study, doesn’t expect a painkiller derived from the venom will be addictive because it blocks a specific channel that transmits pain to the brain. Opiate painkillers, by contrast, block widespread opioid receptors on cells in the brain, spinal cord and other organs.
Spiders aren’t the only venomous creatures with medicinal potential. Researchers in France have found that ingredients in the venom from Africa’s black mamba snake, one of the world’s deadliest, had painkilling properties as potent as morphine. And a drug derived from the venom of the sun anemone, which lives on reefs in the Caribbean, is currently being tested in the U.S. on people with psoriasis and could also be used to treat other autoimmune disorders such as multiple sclerosis and rheumatoid arthritis.
Scientific interest in venom’s painkilling properties stems from an earlier discovery by geneticists of a rare mutation in some people—in a gene known as SCN9A—that eliminates their ability to feel pain. While they can experience touch, warmth and other tactile functions, their sense of smell and pain are inhibited, Dr. Smith said. Some venoms from spiders and other animals and plants have been found to mimic the effects of the gene mutation, she said.
The Australian study analyzed spider venom from 205 species found locally and in other countries (there are currently about 45,000 known species of spiders in the world). The researchers isolated various active peptides from the venom. Each peptide was studied to see how it would affect specific pain targets known as ion channels, which transmit painsignals through the body.
About 40% of the tested spider species contained at least one peptide that blocked pain channels. The researchers plan to conduct animal studies to test the peptides’ clinical potential, looking for any unforeseen side effects, whether the substances break down in the body and other outcomes, Dr. Smith said.
“We’ve got a massive library of different venoms from different spider species and we’re branching out into other arachnids: scorpions, centipedes and even assassin bugs,” Dr. Smith said.
Some, such as the Sydney funnel-web spider, a native to Australia, were easy to milk because they are very aggressive. “Literally, you have to just look at them and they’ll start dripping venom from their fangs,” Dr. Smith said. The spider’s venom, however, didn’t contain ingredients capable of blocking pain channels, she said.
Others, including South American tarantulas the size of dinner plates, had to be anesthetized and the muscles around the venom gland stimulated for venom to be produced, she said. A university researcher traveled the world to collect venoms from spiders kept by arachnid enthusiasts and pet shops.
Australia is a natural fit for this research, Dr. Smith said. “We have a plethora of really good venomous animals: You name it we’ve got it, pretty much. Australia is the venom land.”
The Australian research is funded in part by Janssen Pharmaceuticals Inc., a unit of Johnson & Johnson. “We think this is scientifically promising, but it is too early to put time frames around when this might be in the clinic or a product would be available,” a Janssen spokesman said.
Experiments with the black mamba snake also aim to develop nonaddictive painkillers. The snake, which has olive-gray skin and can grow as long as 12 feet, gets its name from the color inside its mouth, which it displays when threatened.
Researchers at France’s National Center for Scientific Research tested peptides from the black mamba snake’s venom called mambalgins on mice and found potent painkilling properties. The peptides focused on a different pain pathway than the opioid receptors targeted by morphine, according to the research, published in the journal Nature in 2012.
Venom from the sun anemone is being developed into a drug called dalazatide by Seattle-based biotech company Kineta Inc. A human clinical trial with the drug as a treatment for psoriasis recently concluded and results are expected to be released in the next few weeks, according to Kineta. Unlike traditional treatments for autoimmune disorders that suppress the entire immune system, Kineta’s drug is intended to block only the white blood cells that cause the diseases, said company chief executive Charles Magness.
