Poisonous lizard a lifeline for diabetics

A LARGE, poisonous lizard from Mexico has proved to be an unlikely lifeline for diabetics.

The two-foot-long pink and black Gila Monster has a chemical in its saliva similar to a human hormone that helps regulate blood sugar. Last week, a new Type Two diabetes drug based on the lizard chemical was made available.

Exenatide is the first in a new class of medicines known as incretin mimetics. It works by stimulating the pancreas to produce more insulin in response to raised blood sugar, and also influences digestion and appetite.

The garish Gila Monster, Heloderma suspectum, is one of only two venomous lizards in the world and is an endangered species.

Its potent poison, produced by glands in the lower jaw, is used to kill its prey — small mammals and birds. However, the pharmaceutical scientists were more interested in the creature’s spit.

A chemical in the Monster’s saliva, exendin-four, was found to act in a similar way to the human hormone glucagon-like-peptide-one (GLP-one).

In healthy humans, GLP-one stimulates beta cells in the pancreas to produce insulin when blood sugar levels get too high.

But in Type Two diabetics, the GLP-one message system can break down. The signal to make more insulin is weak or missing, and serious illness can result.

Working together, scientists from the drug companies Eli Lilly and Amylin Pharmaceuticals developed an artificial version of exendin-four that can be injected into patients.

The product, exenatide, was launched recently under the brand name Byetta.