The moment the ancestors of mankind were born, insulin was also born and has been working silently through a long evolution. It was not until 1921 A.D. that mankind came to know this close friend of ours.
What is insulin?
Insulin is a protein hormone secreted by the B-cells of pancreatic islets and consists of two polypeptide chains, A and B. The A-chain has 21 amino acids and the B-chain has 30 amino acids, making a total of 51 amino acids, which in general terms are proteins linked by amino acids like egg whites, pork and beef. Insulin is the only known hypoglycemic hormone in the body, helping the body metabolize glucose. The human body is somewhat like an engine, which needs to burn carbohydrates DD glucose to obtain energy and maintain the vitality of life, insulin is just like an essential catalyst in the process of glucose burning, which is the link that sustains life, without it, glucose cannot be burned and the chain of life has to be interrupted.
Since the discovery of insulin to date, its development can be roughly divided into three stages, let’s call it a three-step process.
The first step is animal insulin.
It started in 1921, when Canadian doctor Banting and others first isolated insulin from the pancreatic pancreas of cattle for the treatment of diabetics with success. Since then, people began to extract porcine and bovine insulin from large quantities for the treatment of diabetes. Animal insulin is different in amino acid composition compared with human insulin.
The application of animal insulin has ended the history of diabetes as an incurable disease, but animal insulin is a heterogeneous protein, which is not a family with human, and the human body’s defense system does not recognize it, so the relationship between the two is not harmonious, and thus: 1. easily stimulate the body’s immune system to generate antibodies against animal insulin, which will combine with animal insulin and reduce the efficacy of insulin, and blood sugar will remain high. 2. for some unknown reasons, the antibodies combined with animal insulin will not be able to be used in the treatment of diabetes. For some unknown reason, insulin bound to antibodies will suddenly dissociate, and the level of circulating insulin will suddenly rise in an instant, leading to hypoglycemia.
The second step is human insulin.
To overcome the deficiency of animal insulin, researchers began to explore how to obtain human insulin. The brief history is as follows: In 1963, human insulin was extracted from human cadaver pancreas. 1974, human insulin was chemically synthesized from amino acids. 1979 to 1981, human insulin was biosynthesized by DNA technology, which is to ask the help of E. coli to link amino acids into human insulin.
Today, human insulin synthesized by E. coli is widely used, and its amino acid composition is exactly the same as that of human endocrine insulin. Human insulin is divided into short-acting insulin and medium-acting insulin according to the duration of action, and the latter is made from short-acting insulin by adding appropriate amount of fish sulphate protein and zinc chloride to delay its decomposition. Short-acting insulin is used for injection before meals, while medium-acting insulin is used to supplement insufficient basal insulin secretion.
In the process of application, people still feel some shortcomings of short-acting insulin and medium-acting insulin. The shortcomings of short-acting insulin are: 1. slow onset of action of subcutaneous injection, it must be injected half an hour before eating, long duration of action, lasting about 8 hours, exceeding the digestion and absorption time of food, as a result of which the risk of postprandial hyperglycemia and subsequent hypoglycemia before the next meal increases. 2. poor compliance with subcutaneous insulin injection half an hour before a meal, more than half of the patients cannot eat on time half an hour after the injection (so-called compliance. More than half of the patients cannot eat on time half an hour after the injection (the so-called compliance is whether the patients can strictly follow the doctor’s instructions). The shortcoming of intermediate-acting insulin is that it has a significant peak in action and is used to supplement basal insulin secretion, which can easily cause nocturnal hypoglycemia.
The third step is the modified human insulin DD insulin analogue.
In order to overcome the problem of slow onset of subcutaneous injection of short-acting human insulin and the shortcomings of medium-acting insulin, in the late 1990s, still with the help of E. coli and adjusting the structure of individual amino acids, researchers synthesized fast-acting insulin analogs and long-acting insulin analogs. The former takes effect within 10-20 minutes of subcutaneous injection, the effect lasts only 3-5 hours, and must be injected immediately before meals. It is effective in lowering postprandial blood glucose and reducing the occurrence of preprandial hypoglycemia. The latter has significantly reduced the occurrence of nighttime hypoglycemia because there is no peak effect.
In modern society, people’s life pace is very tight, and the convenience of treatment has a great impact on patients’ compliance. He used to use short-acting insulin, and if he ate less than half an hour after the injection, the insulin did not work, so he had to wait; if he could not eat after half an hour, hypoglycemia would occur, and his life was very rigid, so he simply stopped using insulin often. Later, he switched to a fast-acting insulin analogue and ate immediately after the injection, which eliminated a lot of trouble.
Is it addictive to take insulin?
Both diabetic and non-diabetic patients often ask me: I heard that insulin cannot be taken and once taken, it becomes addictive, is it?
If you have such a question, you may consider answering the following question: Does a healthy life need fresh air? Does a healthy life need clean drinking water? If there is no air or water, can people live? If you answer that air and water are addictive, then you can say that insulin is addictive and I will not object. If you answer that breathing air and drinking water are not addictive, then you should not say that insulin is addictive either, otherwise I will strongly oppose it.
The origin of the misconception has something to do with the essential nature of insulin.
In healthy people, the pancreatic B cells in the pancreas continuously secrete insulin into the blood to maintain the balance of the internal environment and ensure metabolism, so that life and health are free from worry. In the case of diabetic patients, insulin is not enough, and in the case of severe cases, pancreatic B cells are completely shut down and no longer secrete any insulin; in the case of severe cases, diabetic ketoacidosis occurs and life is dying, so non-insulin cannot save life and cannot return to life. Lay people, because of the limitation of knowledge, can not fully understand the causes and consequences of the matter, but only for some diabetic patients can not survive without insulin impressed, so one-sided determined that: insulin addiction. This is a fallacy that confuses a large number of people.
So far, we understand that when you are healthy, insulin is the unsung hero, working perfectly and silently. If, unfortunately, diabetes strikes one day and the flower of life gradually withers and fades, insulin must be replenished from outside the body in time to keep life fragrant and splendid. Insulin is becoming more and more amiable through the development and progress of animal insulin, human insulin and insulin analogues, and we believe it will have a more amiable tomorrow.