Why is the natural insulin secreted by snails so effective?

The natural insulin secreted by snails is highly effective, acting three times faster than artificial insulin

The official website of the University of Utah in the United States released a notice on the 12th stating that researchers from the university, in collaboration with Australian counterparts, discovered the molecular structure of insulin in the venom produced by snails when hunting prey. This natural insulin can regulate blood sugar levels in just 5 minutes, while the fastest-acting artificial insulin currently available takes 15 minutes to take effect.

Human insulin is a hormone secreted by the pancreas that is related to glucose uptake, and it contains an A region and a B region. Diabetes is generally caused by damaged pancreatic function that prevents normal insulin secretion, and the most effective current treatment is injecting artificial insulin. However, the B region within insulin causes insulin molecules to aggregate into polymers of 6 molecules. Injected insulin must be degraded from aggregates into single molecules before it can take effect in patients, and this degradation process often takes one hour. Even the fastest insulin on the market still requires 15 to 30 minutes to take effect. Scientists had attempted to remove the B region, but the consequence of doing so was that the insulin completely lost its efficacy.

The paper by university biologist Helena Safavi, published in the journal Nature Structural & Molecular Biology, describes that they found the insulin in snail venom does not contain the B region, and therefore does not cause insulin molecules to aggregate. Laboratory tests show that although it is not as potent as human insulin, snail insulin still has blood-sugar-lowering function and can take effect rapidly within 5 minutes.

When snails hunt fish, they often secrete some venom into the water, causing the blood sugar of nearby fish to rise to a peak and then drop rapidly, making the fish faint, so the snail can enjoy a full meal. Through long-term fish-hunting activity, snail insulin continuously evolved and acquired a rapid-response function.

In the next step, the researchers will continuously modify the structure of artificial insulin based on the structure of snail insulin so that the latter can also maintain its blood-sugar-lowering effect after losing the B region; they will also test the efficacy of injecting snail insulin or modified human insulin into organisms. In addition, the researchers are also studying artificial pancreas devices that simulate the human pancreas's function of automatically delivering insulin doses into the body according to blood sugar levels. This device may be successfully developed next year, and in the future snail insulin may be used in artificial pancreas devices. (Reporter Nie Cuirong)