Through gene therapy, scientists at Ariad Pharmaceuticals in Cambridge, Massachusetts, have come up with a way to store insulin in cells that can be released only when a pill is taken. Published in the February issue of Science, the findings hold promise not just for the treatment of diabetes, but for other medical problems which require a timed-release technique.
In the experiment, the researchers inserted insulin-producing genes and a protein into cells. Once inside the cells, the genes and the protein stick together and form clumps which are too big to leave the cell. The cells were then injected into the muscles of diabetic mice. Some of the mice were fed a drug which broke up the protein clump and released the insulin into the blood stream. The blood glucose level in these mice dropped as a result. According to lead researcher Tim Clarkson, the amount of insulin that gets released is directly related to the amount of drug given. So, consuming a larger dose of drugs would allow for a larger release of insulin. When no drug is taken, the insulin remains in the cell, causing no toxicity or adverse effects.