Hereditary diseases of carbohydrate metabolism
Carbohydrates are complex organic compounds that perform in the human body a number of important functions.Carbohydrates, consisting of one molecule, called monosaccharides;of two related molecules - disaccharides;of several molecules related to each other, - polysaccharides;consisting of a few simple carbohydrates - oligosaccharides.The main monosaccharides human body are glucose, fructose, galactose and ribose.Disaccharides and oligosaccharides are included in various food products.In addition, the flora and fauna are common polysaccharides.The most important function of carbohydrates in the human body is to provide energy to all of the processes occurring in it.Carbohydrates are also used as a building material, as a component of the ground substance of connective, osseous and cartilaginous tissues.They perform a number of specific functions in particular are the building blocks of the human body secretion glands (eg salivary).Carbohydrates such as ribose and deoxyribose, the main component of DNA and
in the blood of an adult carbohydrate fructose generally can not be detected, but in utero, it is a normal component of the blood of the fetus.This is peculiar metabolism in this age period.Exchange glucose after its absorption in the intestine determined by the needs of the body for energy and tissue oxygen supply.With the shortage of energy is degraded to glucose, lactic acid, and the absence of oxygen in the tissue at this stage glucose exchange stops.Under conditions of sufficient oxygen in the tissues of the human body there is a further process of breakdown of glucose to the final products, which are carbon dioxide and water.As the breakdown of glycogen contained in the liver, and the oxidation of lactic acid in the absence of sufficient oxygen are directed to compensation of energy expenditure of the body.The process of glycogen breakdown in the absence of oxygen is accompanied by the formation of a certain amount of energy used for the life of the organism.The conversion of glucose to lactic acid is also accompanied by release of energy.This process takes place with the participation of 13 enzymes.The process of splitting glucose to carbon dioxide and water results in the formation of such a quantity of energy which is 15 times the amount of energy produced when the liver glycogen breakdown in the absence of oxygen in body tissues.The process of anoxic glycogen breakdown is more ancient mechanism for the human body with energy.Contents
glucose (sugar) in the blood is determined by certain factors, which include: the amount of glucose coming from the intestine, glucose uptake into the blood from organs that are its depot (mainly from the liver), the formation of glucose from other metabolic products.The amount of sugar in the blood is regulated by hormones, the main of which is the hormone of the pancreas - insulin.This hormone of glucose promotes the formation of a substance such as glycogen.Last accumulates in the liver and, if necessary subjected to the inverse transformations which result in glucose formed again.In addition, insulin promotes glucose uptake in the various cells of the body where a result of numerous transformations generated energy necessary for life processes.With a lack of basic substances which is formed from glucose, are distinguished from the adrenal hormones trigger mechanisms glucose production from other starting materials.Insulin increases the utilization of glucose by peripheral tissue, reduces blood sugar, liver glycogen content and increase its content in muscle.
Another hormone pancreas - glucagon - also has a multilateral influence on glucose metabolism, while its effect is largely similar to the effect of adrenaline.Under the influence of the glucagon and epinephrine enhanced breakdown of glycogen in the liver tissue glucose uptake but it remains unchanged, thereby increasing blood sugar.Thyroid hormones increase metabolic rate of carbohydrates and mobilize depot, though blood sugar no effect.While growth hormone (somatotropin) inhibits the formation of glucose from other starting materials and simultaneously increases its degree of liver glycogen in the blood glucose level does not change.A newborn child process of carbohydrate metabolism regulation has not yet developed completely, which explains the decrease in blood glucose during the first days after birth.As a rule, restoration of normal glucose level occurs at 5-10 days of life.The reason for the reduced amount of glucose in the blood of newborns is the lack of maturity of the mechanisms of its formation of liver glycogen.Of great importance is also the restructuring of the endocrine system that occurs in the first days of life.Receipt or glucose production during certain periods of the day may exceed the energy requirements of the body at this time point, in which case it is stored in the cells of the liver as glycogen.Reduction of blood glucose is a signal to reverse the formation of glucose from glycogen.
great importance for the detection of hereditary diseases of carbohydrate metabolism are methods of qualitative and quantitative determination of carbohydrates in the body fluids, the main of which is the blood.In order to quickly determine the content of glucose in the urine test strip are special paper.However, this method is relatively accurate only in connection with the fact that it only detects the presence of glucose and its estimated amount.These data are obtained by changing the color of the test strip after placing it in the urine test.
has a load test to detect diseases of deposit of great importance to glycogen.In this case, galactose drink investigated proposed solution with a certain amount of it, and then determine the content of glucose in the blood.In some cases, to clarify the type of the disease is necessary to study the activity of enzymes involved in glucose metabolism.These enzymes are found in muscle, liver and certain other organs.Research carried out on pieces of body tissue that is taken during a special method called a biopsy.