“Smart” insulins, which are undergoing trials, could revolutionize the way diabetes is managed, scientists say.

Instead of repeated blood tests and injections throughout the day to keep blood sugar in check, a single dose of smart insulin would keep circulating in the body and turn on when needed.

Animal studies show the technology appears to work – at least in mice.

Scientists plan to move to human trials soon, PNAS journal reports.

Experts caution that it will take years of testing before treatments could become a reality for patients.

People with type 1 diabetes, who either do not make or cannot use their own natural insulin, rely on insulin injections to stay well.

Without these, their blood sugar would get dangerously high.

In the same time injecting insulin can also make blood sugar levels dip too low, and people with type 1 diabetes must regularly check their blood glucose levels to make sure they are in the right zone.

Diabetes experts have been searching for ways to make blood sugar control easier and more convenient for patients, which is where “smart” insulins come in.

There are a few different types in development, but all are designed to automatically activate when blood sugar gets too high and switch off again when it returns to normal.

Dr. Danny Chou from the Massachusetts Institute of Technology (MIT) has been testing a smart insulin that he and his colleagues developed in the lab.

It is a chemically modified version of regular, long-acting insulin.

It has an extra set of molecules stuck on the end that binds it to proteins that circulate in the bloodstream. While it is attached to these, the smart insulin is in its switched off mode.

When blood sugar rises, the smart insulin switches on – glucose locks on to the smart insulin and tells it to get to work.

Dr. Danny Chou said: “My goal is to make life easier and safer for diabetics.

“This is an important advance in insulin therapy.”

The Juvenile Diabetes Research Foundation (JDRF) has been funding work into smart insulins.

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