While the exact cause of type 1 diabetes is unknown it is thought to be an autoimmune disorder in which the body attacks cells in the pancreas that produce insulin, a hormone that causes blood sugar to be taken up by cells and used for energy. In type 1 diabetes the pancreas makes little or no insulin, leading to high levels of sugar in the blood which can lead to blindness, limb amputation and kidney failure. Untreated, the disease is fatal.
Right now type 1 diabetes patients have to receive insulin shots, several times a day, for the rest of their lives to keep blood sugar levels under control. And there’s added risk if the patient’s dose isn’t correct – too much insulin is harmful too. The new device would relieve patients of the need to monitor and control their own blood sugar levels by controlling them automatically.It is comprised of a network of nanoparticles that releases insulin into the blood in response to changes in blood glucose levels. Each of the nanoparticles have a core of insulin, a charged molecular chain called dextran and the enzyme glucose oxidase. When blood glucose levels are high, glucose oxidase breaks the sugar down into gluconic acid, which then breaks down the dextran chains to release insulin. The gluconic acid and dextran are broken down by the body and the released insulin returns blood sugar levels back to normal. The degradable nano-network was shown to work in mice where a single injection kept blood glucose levels normal for a minimum of 10 days.
“This technology effectively creates a ‘closed-loop’ system that mimics the activity of the pancreas in a healthy person, releasing insulin in response to glucose level changes,” Zhen Gu, lead author of the study and an assistant professor in the joint biomedical engineering program at North Carolina State and University of North Carolina Chapel Hill, said in a press release.
The study was published recently in the Journal of Agricultural and Food Chemistry. The next step, the researchers say, is to test the technology in humans.
The current technique works in principle similarly to the ‘Silicon Pancreas,’ a microchip that regulates blood sugar levels by mimicking both the insulin-producing beta cells and glucagon-producing alpha cells in the pancreas. The current technique is more elegant in its simplicity, however, as the Silicon Pancreas requires a separate blood sugar level monitor embedded in the skin.
Diabetes affects 366 million people worldwide. It’s the seventh leading cause of death in the United States where 25.8 million children and adults, or 8.3 percent of the population, have the disease. And as people continue to grow in size, so will diabetes as an epidemic, and devices such as the one developed by Dr. Zhen and colleagues will be needed more than ever.