‘Smart’ insulin could offer better control of blood sugar levels for people with type 1 diabetes

Engineers at Massachusetts Institute of Technology (MIT) hope to improve treatment for people with type 1 diabetes with a new type of engineered insulin.

The researchers showed, following tests in mice, that the modified insulin could circulate in the bloodstream for at least 10 hours, and that it responds quickly to changes in blood sugar levels. This could remove the need for people with type 1 diabetes to repeatedly monitor their blood sugar levels and inject insulin throughout the day.

A new form of 'smart' insulin could help people control blood sugar levels

Daniel Anderson, the Samuel A. Goldblith Associate Professor in MIT’s Department of Chemical Engineering, and a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science, said: “The real challenge is getting the right amount of insulin available when you need it, because if you have too little insulin your blood sugar goes up, and if you have too much, it can go dangerously low. Currently available insulins act independent of the sugar levels in the patient.”

Daniel Anderson and Robert Langer, the David H. Koch Institute Professor at MIT, are the senior authors of the Glucose-responsive insulin activity by covalent modification with aliphatic phenylboronic acid conjugates report, describing the engineered insulin in a recent issue of Proceedings of the National Academy of Sciences.

The MIT team set out to create a new form of insulin that would not only circulate for a long time, but would be activated only when needed — that is, when blood-sugar levels are too high. This would prevent people with type 1 diabetes’ blood-sugar levels from becoming dangerously low, a condition known as hypoglycaemia.

To create this glucose-responsive insulin, the researchers first added a hydrophobic molecule, called an aliphatic domain, which is a long chain of fatty molecules dangling from the insulin molecule. This helps the insulin circulate in the bloodstream longer, although the researchers do not yet know exactly why that is. One theory is that the fatty tail may bind to albumin, a protein found in the bloodstream, sequestering the insulin and preventing it from latching onto sugar molecules.

Professor Anderson said: “The modified insulin was able to give more appropriate control of blood sugar than the unmodified insulin or the long-acting insulin.”

He added that giving this type of insulin once a day instead of long-acting insulin could offer people with type 1 diabetes a better alternative that reduces their blood-sugar swings, which can cause health problems when they continue for years and decades.

The researchers now plan to test this type of insulin in other animal models and are also working on tweaking the chemical composition of the insulin to make it even more responsive to blood-glucose levels.