What is insulin?

Insulin is a protein hormone, which is secreted by islet β cells in the pancreas.

Insulin participates in regulating glucose metabolism and controlling blood sugar balance, and can be used to treat diabetes.

Insulin is the only hormone that lowers blood sugar and promotes the synthesis of glycogen, fat and protein. The mechanism of action belongs to receptor tyrosine kinase mechanism.

After insulin was discovered by Wanjin and Best, it began to be used in clinic on 1922, saving the diabetic patients who died in the past. Until the early 1980s, almost all insulin used in clinic was extracted from the pancreas of pigs and cows. The insulin composition of different animals is different, and the insulin structure of pigs and humans is the most similar, only one amino acid at the carboxyl end of B chain is different. In the early 1980s, human insulin was successfully produced from microorganisms by genetic engineering technology, and it has been applied in clinic.

From 65438 to 0955, the whole amino acid sequence of bovine insulin was determined by the team of F. Sanger in Britain, which opened a way for human to understand the molecular chemical structure of protein.

1965 September 17, scientists in China synthesized crystalline bovine insulin with complete biological activity, which is the first protein synthesized artificially in the laboratory. Later, scientists in the United States and the Federal Republic of Germany also completed similar work.

In the early 1970s, scientists in Britain and China successfully determined the three-dimensional structure of porcine insulin by X-ray diffraction. These works laid a foundation for further study on the relationship between molecular structure and function of insulin. People prepare analogues by chemical total synthesis and semi-synthesis, and study the influence of their structural changes on biological functions; Compare different kinds of insulin; To study abnormal insulin molecular diseases, that is, molecular diseases caused by the mutation of insulin gene changing a single amino acid in insulin molecule. These studies also have important practical significance for clarifying the causes of some diabetes.

"Diabetes" is a disease in which glucose in the blood tends to accumulate too much. Known as "silent killer" abroad, especially "adult diabetes", the infection rate of middle-aged people over 40 years old is particularly high. In Japan, the population over 40 years old accounts for 10%, that is, one in ten people has diabetes. Once suffering from "diabetes", life expectancy will be reduced by as much as ten years, and possible complications will spread all over the body.

"Diabetes" itself also brings great pain to people. It often makes people feel thirsty and want to drink water, and they wake up many times in the middle of the night because of excessive urination. Although I eat a lot, I still feel hungry, lose weight, sleep and so on. It always makes people feel that something is wrong with me. By the time you can feel something obvious somewhere, the condition of "diabetes" has developed to a certain extent. Terrible complications are creeping around the body.