'Smart insulin' shows promise in mice with type 1 diabetes

Date: Feb-11-2015 Patients with type 1 diabetes have to test their blood several times a day to

check their sugar levels and assess how much insulin to inject into themselves. Any lapse

or miscalculation in this unrelenting regimen can lead to serious health complications and even death.

Tests on mice with a form of type 1 diabetes showed that one injection of "smart insulin" works for at least 14 hours.

Now, a new study by Danny Chou, an assistant professor of biochemistry at the

University of Utah School of Medicine in Salt Lake City, and colleagues suggests this

burden could one day be considerably lighter for people with type 1

diabetes.

Writing in the Proceedings of the National Academy of Sciences, the team

describes how they developed and tested a long-lasting "smart insulin" compound called

Ins-PBA-F that self-activates when blood sugar is high and brings it back to normal

levels.

The researchers are now developing the smart insulin into a therapy suitable

for human use. They anticipate it being ready for clinical trials in 2-5

years.

Tests on mice with a form of type 1 diabetes showed that one injection of Ins-PBA-F

works for at least 14 hours. During this period, the smart insulin activated several

times in response to blood sugar rising after the mice were given amounts of sugar

comparable to that consumed at mealtimes.

Smart insulin responds faster and more effectively than current drugs

Both type 1 and type 2 diabetes are diseases where the body is unable to control blood

sugar. This is most pronounced in type 1 diabetes, which arises when the beta cells in

the pancreas that produce insulin are destroyed.

Without insulin, the body has no mechanism for moving sugar out of the blood and into

cells, where it is used for energy. People with type 1 diabetes are completely dependent

on their daily insulin injections for their survival.

Fast facts about diabetes

In 2012, 9.3% of Americans - 29.1 million people - had diabetes
Around 5% of diabetes patients have type 1 diabetes
The total cost of diagnosed diabetes in the United States in 2012 was $245

billion.

Find out more about diabetes

If a person with type 1 diabetes fails to manage their blood sugar properly, they can

do serious damage to their health, or worse. Hyperglycemia, or high blood sugar, can lead

to heart disease, blindness and other long-term complications. Hypoglycemia, or low blood

sugar, can result in coma and even death.

The researchers suggest their smart insulin Ins-PBA-F could give a faster, more

effective response to lowering blood sugar than the current long-acting insulin drug

detimir, which is marketed under the brand name LEVIMIR.

The study results showed that the speed and chemical reactions of Ins-PBA-F

normalizing blood sugar in diabetic mice are the same as in healthy mice responding to

blood sugar changes with their own insulin.

Prof. Chou says the study "is an important advance in insulin therapy," and adds:

"Our insulin derivative appears to control blood sugar better than anything

that is available to diabetes patients right now."

Although diabetes treatments have advanced considerably in recent decades - insulin

pumps are now available and there are four types of insulin - patients must still make

their assessment and adjust the dose themselves. The amount of insulin they need can be

different each time depending on various factors, such as what they have eaten and how

much exercise they do.

A smart insulin drug that automatically activates in response to rising blood sugar

would get rid of the need for top-up shots of insulin, and eliminate the danger of

incorrect dosing.

Ins-PBA-F 'first in its class' to fit true definition of 'smart' insulin

Ins-PBA-F is not the only smart insulin drug currently under development, but it is

the only one that does not rely on being coated with a gel or protein barrier to inhibit

insulin when blood sugar is low. Such products carry the risk of unwanted side effects

such as an immune response, note the researchers.

Instead, Ins-PBA-F works because it has a tail made of phenylboronic acid (PBA) that

under normal conditions binds Ins-PBA-F to circulating blood proteins that block its

effect. But when blood sugar rises, the sugars bind to the PBA making it trigger the

release of Ins-PBA-F so it can get to work and bring the sugar levels back to normal.

Prof. Chou says:

"Ins-PBA-F fits the true definition of 'smart' insulin, where the insulin

itself is glucose responsive. It is the first in its class."

Funds for the study came from the National Institutes of Health, the Juvenile Diabetes

Research Foundation, the Harry B. Helmsley Charitable Trust and the Tayebati Family

Foundation.

Meanwhile, Medical News Today recently learned how researchers may have

found a novel way to cure diabetes using a probiotic.

The team - from Cornell University in Ithaca, NY - successfully reduced blood glucose levels in

diabetic rats by up to 30% with the help of engineered human gut bacteria that

reprogrammed cells in the animals' intestines to produce insulin.

Written by Catharine Paddock PhD

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.