Help could be on the way for the hundreds of millions of diabetics who are tired of giving themselves daily insulin injections. Scientists from India's National Institute of Pharmaceutical Education and Research have recently had success in orally delivering insulin to rats' bloodstreams.
There are two main reasons that diabetics aren't already just taking insulin pills – digestive enzymes break insulin down before it can be taken up by the body, plus it's difficult for insulin to enter the bloodstream from the gut.
In order to protect the insulin from the enzymes, the researchers started by packaging it in liposomes – tiny man-made hollow spheres composed of lipids (in this case, those lipids were fat molecules). The liposomes were then coated with layers of protective polyelectrolytes, becoming what are referred to as "layersomes."
The scientists subsequently also attached folic acid to each sphere, as previous studies had shown that it allows liposomes to be absorbed through the intestinal wall and into the bloodstream.
When the finished layersomes were given to rats orally, they lowered the animals' blood glucose levels by almost the same amount as injected insulin. What's more, the effect lasted longer.
A paper on the research, which was led by Dr. Sanyog Jain, was recently published in the journal Biomacromolecules. Scientists in North Carolina are also developing an alternative to daily insulin injections, although they're exploring the use of pulsed ultrasound.
Source: American Chemical Society