Amylin is a hormone created in the pancreas that is normally released at the same time as insulin. The hormone works with insulin to move glucose from the blood into body cells, lowering blood glucose levels. It slows down the movement of food through the stomach, and so curbs the rise in blood glucose levels. Amylin stops the release of extra glucose from the liver that can make blood glucose levels climb. It also helps control hunger by signaling the brain that you are full. Those with type 2 diabetes produce less of this hormone than necessary, while those with type 1 diabetes no longer produce any amylin.
Pramlintide, an amylin analogue (or copy), is a man-made injectable drug that works in much the same way. Those who have not been able to control after-meal blood glucose levels using insulin could add pramlintide to bring levels down. Pramlintide must be injected before each meal. Since it cannot be mixed in the same syringe with insulin, three more daily injections would be required.
In studies, pramlintide lowered A1C in people with type 1 and type 2 diabetes about 0.4 to 0.6 per cent. (A1C measures three-month average blood glucose). Weight loss was another benefit observed in studies. People with type 1 diabetes lost an average of 0.5 kg, while those with type 2 diabetes lost 0.5 to 1.4 kg.
Since it makes insulin more effective, pramlintide may increase the risk of low blood glucose. Those starting on pramlintide must lower the amount of insulin to prevent this occurrence. Another common side effect is mild nausea, which appeared in about 30 per cent of people. Nausea usually disappears after a few weeks. However, it may help to start with a low dose of pramlintide and gradually increase the amount taken.
Pramlintide is the first new drug used to treat type 1 diabetes since insulin was developed. If approved, it will be another tool that can be used to help reach target blood glucose levels.
When you eat, hormones called incretins that cause your pancreas to release more insulin are released in the gut. Glucagon-like peptide-1 (GLP-1) is one of these hormones. The higher the blood glucose level, the more insulin it spurs your body to release. It also stops the liver from releasing extra glucose, slows down the movement of food, and controls appetite. Studies have also shown that GLP-1 can slow damage to cells in the pancreas that produce insulin. Such cell damage is what makes type 2 diabetes worse over time. Those with type 2 diabetes have less of the GLP-1 hormone.
Exenatide (an insulin mimetic) is an injectable drug that duplicates the action of GLP-1. Exenatide has been taken by people with type 2 diabetes who are on metformin, a sulfonylurea or both. It is injected twice daily, before the morning and evening meal.
Studies with exenatide showed that A1C levels were lowered by 0.4 to 0.9 per cent. It also caused weight loss of 0.9 to 2.8 kg. Those who continued taking exenatide experienced even more weight loss.
If you take a sulfonylurea, exenatide may increase your risk of low blood glucose. The sulfonylurea dosage may need to be lowered. Mild to moderate nausea is another side effect that usually lasts only a few weeks.
Exenatide and liraglutide (another insulin mimetic) may help patients with type 2 diabetes reach their blood glucose targets. The added benefits of weight loss and protection of the cells that produce insulin make these drugs very appealing.
New injectable insulins
Insulin glulisine is a rapid-acting insulin that works the same way as insulin aspart and insulin lispro. It starts to lower blood glucose almost immediately after injection and its action matches the blood glucose rise after meals. This insulin adds another option to the two rapid-acting insulins currently available.
Insulin detemir is a long-acting insulin very similar to insulin glargine. It has peakless action that lessens the chance of low blood glucose occurring during the night. It may have to be injected twice daily for people with type 1 diabetes and once or twice daily for those with type 2 diabetes. Insulin detemir will allow another long-acting insulin option.
Researchers have been searching for decades to find an alternative to insulin injection. Scientists are now testing both liquid and dry powdered insulin designed to be inhaled.
A device about the size of a can of tennis balls would be used to inhale the insulin. Once the insulin reaches the lungs, it is absorbed into the blood very quickly. Inhaled insulins act similarly to rapid-acting insulins. Since there are currently no longer-acting inhaled insulins, some injections would still be necessary.
To date, the only common side effect found is a cough that seems to lessen with time. Studies have shown that smokers would not be able to use this insulin since it is absorbed into the bloodstream too quickly. Those with asthma or other chronic lung diseases such as cystic fibrosis could also potentially have problems. More long-term studies are being done to find out whether inhaled insulin has any effect on lungs or breathing when used over a number of years.
Real-time Continuous Glucose Monitoring Systems (CGMs)
Interstitial fluid is the liquid in the spaces between our body’s cells. A new device that measures the level of glucose in this fluid has recently been developed. A tiny, plastic tube called a cannula is inserted under the skin into the interstitial fluid. This cannula is connected to a glucose sensor attached to the skin with an adhesive patch. The glucose sensor converts the glucose level into an electronic signal. This signal is sent to a monitor where it is displayed on a screen. The monitor is about the size of a calculator, works up to six feet away, and could be carried in a pocket or purse. The device usually lasts three days. After that, a new set is inserted at another spot. Most people wear the device on their abdomen.
After a two-hour initialization period, interstitial glucose readings are given every five minutes. This information can be used to determine glucose patterns and see what effect food, medications, and activity have on glucose levels. An alarm can be set to go off when interstitial glucose levels become too high or low.
This device does not eliminate the need for fingerstick measurements. Interstitial fluid glucose values can be about ten minutes behind fingerstick blood glucose levels when glucose levels are rising or falling very quickly. A fingerstick blood glucose is required to confirm a sensor reading before making glucose management decisions. The CGM also needs to be calibrated twice a day with a glucose level from a blood glucose meter.
The future is bright . . .
Those diagnosed with diabetes before the discovery of insulin less than a century ago had a very bleak future. Since that time, the discovery of new medications and technologies has improved the quality of life for all people with diabetes. Scientists are constantly making new discoveries that make it easier to cope with a diabetes diagnosis. Who knows what the future has in store?