Insulin for Diabetes Mellitus

Journalist | Lee Dawon | dalee5451@yonsei.ac.kr

Designer | Lee Seungwoo | seungwu210@yonsei.ac.kr

Insulin is a hormone that plays an important role in maintaining glucose homeostasis. It promotes the absorption of glucose from the blood into body cells, such as fat, liver, and skeletal muscle cells, lowering blood glucose levels. Excess glucose is stored in the form of glycogen to form energy. The beta cells of the endocrine pancreas secrete insulin in response to a high level of glucose.

Deficient or absent insulin action impairs the body’s ability to take up and use glucose as the primary energy source. The failure to control blood sugar levels within a narrow range causes diabetes mellitus.

One type of this disease is called diabetes mellitus type 1, which usually occurs in children. Type 1 diabetes occurs when the immune system destroys beta cells. Breaking down the manufacturing system of insulin results in insulin deficiency, and the incapability of regulating the level of glucose. 15% of diabetes patients belong to this type. These patients are treated by insulin injection, fulfilling the lacking hormone. If this type 1 diabetes is not treated promptly, a severe shortage of insulin can develop and incur diabetic coma.

Another type is diabetes mellitus type 2, which is more common in adults. Unlike type 1 diabetes, the beta cells of type 2 diabetes can synthesize insulin, even though the amount of insulin is not enough. Instead, the reactivity in target cells of insulin reduces. These cells become resistant to insulin, not responding to lower blood sugar. Furthermore, serious complications such as heart disease, vision loss, and kidney disease can develop. Some type 2 diabetes patients also take insulin as a medication.

Currently, insulin is used in the form of a hypodermic injection. The first option is shots or pens. Insulin can be injected by using a needle, a pen device, or a syringe into the fat. Recently, insulin pens are often used, as the syringe is inaccurate in preparing the insulin dose. Pen needles are developed to be shorter and thinner, incurring less pain. These injections should be done several times each day depending on the blood sugar levels. Another option is the insulin pump. Insulin is delivered separately during the day using an inserted thin tube underneath the skin. It has a sensor, which continuously monitors the levels of glucose. The sensor reduces human errors, improving glycemic control in patients. Both methods require penetrating through the skin, stirring up fear and discomfort. Also, only a small amount of insulin that enters the bloodstream reaches the liver by injection. Those disadvantages of insulin delivery demand an alternative, other than the injection.

If injecting insulin causes pain in the patients, then people can wonder why pharmaceuticals are not producing oral insulin. However, barriers to oral insulin exist regarding its constituent and, - protein. Until now, no other type of hormone has been taken orally because protein-digesting enzymes would attack and convert hormones into a useless form, amino acids. Therefore, these hormones must be administered by non-oral routes; for example, insulin injections. Insulin deficiency is treated with daily injections of insulin.

A movement to change the mode of insulin delivery orally is arising to better diabetes patients and to jump the hurdle of protein-digesting enzymes. Lately, one of the pharmaceutical companies that worked on developing oral insulin is “Oramed Pharmaceuticals (NASDAQ: ORMP)”. A soft gel insulin capsule named “ORMD-0801” uses a protease inhibitor to endure under the condition of proteolytic enzyme and absorption enhancer to permeate the membranes of the intestine. It was designed to dissolve in the small intestine though they failed to achieve ORMD-0801 in the phase 3 clinical trial. Still, -attempts to invent oral insulin are worthwhile. Every attempt to manufacture new drugs will contribute to improving the lives of diabetes patients eventually. B