How toxic marine venom could become vital medicine

The toxic venom of a marine snail could be the basis of new treatments for hormone disorders and diabetes.

A study has found the geography cone (Conus geographus), native to the Indo-Pacific region, has a substance that can regulate blood sugar and hormone levels.

The venom is also deadly, so it can’t be rushed straight to the pharmacy. But the researchers say that it could be a useful starting point for making new pharmaceuticals.

“Cone snails are just really good chemists,” says Dr Ho Yan Yeung,  postdoctoral researcher at the University of Utah, USA, and lead author on a paper published in Nature Communications.

Many medicines are based on naturally occurring products, including fatal ones. Cone snails themselves have been the inspiration for other pharmacological work, such as helping to understand why antidepressants can combat nerve pain.

This international team of researchers has found that the geography cone’s venom contains a toxin that behaves like the human hormone somatostatin, which plays a regulatory role throughout the body.

The researchers collected cone snails from the central Philippines for this study.

“Conus geographus can be aggressive and has been reported to have killed people – about 40 human fatalities have been reported,” says senior author Dr Helena Safavi, an associate professor of biochemistry at the University of Utah, USA.

Safavi tells Cosmos that while collecting cone snails is “potentially dangerous”, the team is “very experienced in collecting cone snails from the field and take several precautions”.

The researchers use long tongs to move the snails into big plastic boxes, designed for lionfish, on their collection missions.

“When we get back to the boat we transfer the snails to a bucket and take them back to the lab where we continue to handle them with great care,” says Safavi.

The team extracted venom from the snails and tested one specific compound they were interested in, called Consomatin pG1, in petri dish-based experiments on human cells.

Consomatin is a similar compound to somatostatin, but while somatostatin interacts with a range of different proteins in the human body, consomatin interacts with just one.

This means that while somatostatin regulates all sorts of hormones and sugars, consomatin controls just blood sugar levels and some related hormones. It’s more targeted than synthetic drugs designed to regulate these hormones.

“These [drugs] are used to visualise and treat certain types of cancers (neuroendocrine cancers) and growth hormone disorders such as acromegaly,” says Safavi.

“We think the cone snail developed this highly selective toxin to work together with the insulin-like toxin to bring down blood glucose to a really low level,” says Yeung.

In combination with insulin, consomatin is dangerous, but a molecule like it could be designed to treat these disorders more effectively.

“The next steps for us are to use this and other cone snail consomatins to make drug analogs that can be used to detect and treat different types of neuroendocrine cancers, and also make analogs that can be used as new pain therapeutics,” says Safavi.

The team has also been investigating painkillers, with a recent preprint published on the subject.