Enzymes are defined as “promoters of chemical actions.” It is the nature of all living organisms to perform quickly a number of re-actions which, outside of such an organism (e.g., in the laboratory) require long periods of time and special laboratory conditions. In the human body all sorts of actions and reactions take place.
The various biochemical, biophysiological and biopathological actions and reactions take place because of the various enzymes which regulate the processes of the living organism, both in health and in sickness.
The reader is no doubt acquainted with a number of enzymes from general knowledge. One example is the ptyalin of the saliva. This enzyme promotes the digestion of starch, when the food is properly insalivated and chewed. Other familiar enzymes of the digestive tract are pepsin and rennin, two protein digestive enzymes that are found in the stomach. The intestines produce enzymes that promote the digestion of fat, sugar and starch, and also protein.
More complex and less familiar enzymes are the glandular products. These substances regulate the growth, health, well-being, happiness or misery of the individual. An example of one of these enzymes is thyroxin, the basic product of the thyroid glands. The hormones of the sex glands illustrate another type of enzymes. There are enzymes in various tissues that promote their nutritive functions. In disease, the body turns either fat or thin through the action or lack of action of enzymes.
Among other enzymes that play a role in disease are those that produce autolysis. For example, a tubercular lung may disintegrate through the action of enzymes as well as of TB organisms. Cancerous tissue often disintegrates because of characteristic pathogenic enzymes. An ulcer of the stomach or elsewhere may be produced by pathogenic enzymes.
Body chemistry as applied to human health and disease is not as yet well understood in leading and authoritative medical circles. A textbook such as the one by Professor Morse on bio-chemistry is a classic. It has a wealth of information that throws light on human health and disease. This textbook was published by Saunders in 1927 and contains much enlightening scientific information about the chemical processes of the body.
The liver contains a number of chemical activators which are also classed as enzymes. It produces a product known as secretin, which activates the production of insulin by the pancreas.
There are other enzymes that regulate the health of the body, and also other enzymes that disintegrate tissues in the course of disease. In the late stages of cancer, TB or diabetes, there is a wasting of the tissues. Diabetic gangrene in terminal structures may be caused in a measure by enzyme action. Spontaneous fracture of bones is caused by a lack of minerals and vitamins in the bone structures; but certain types of enzymes may be responsible for this form of degeneration.
Enzymes produce the miraculous changes taking place in the budding of trees and shrubs and the production of fruit. All the living things that grow on this planet owe their being to enzymes, those wonderful promoters of chemical action. They also account for the fact that certain fruits which are picked while still unripe (like bananas, avocados and tomatoes) ripen at the proper temperature even after they have been separated from the plant which nourished them.