VIOLATIONS OF CARBOHYDRATE METABOLISM
Violation of hydrolysis and absorption of carbohydrates
Absorption of carbohydrates is violated at failure of amylolytic enzymes of the gastrointestinal tract (pancreatic juice amylase, etc.). In this situation carbohydrates that come from food are not broken down to monosaccharides and are not absorbed. Carbohydrate starvation is developed. Absorption of carbohydrates is violated in inflammation of the intestinal wall, resulting in impaired glucose phosphorylation. This happens in cases of poisoning of toxins that block the enzyme hexokinase.
Glycogenosis
Glycogenosis is a group of inherited diseases caused by deficiency of enzymes involved in synthesis or breakdown of glycogen.
Glycogenosis of 0 type occurs under glycogen synthase deficiency. It is characterized by a sharp decrease of glycogen in the liver, there is a condition until the development of coma (hypoglycemic syndrome). Patients with glycogen synthase deficiency die at an early age.
Lack of enzymes involved in the breakdown of glycogenleads to its accumulation in organs and tissues (Table 1).
Table 1. The diseases associated with metabolic disorders of glycogen.
| Name of disease | Causes | Symptoms |
| Gierke's disease, glycogen storage disease type I | Hereditary defects of synthesis of glucose-6-phosphatase in liver and kidney | Enlargement of liver (hepatomegaly), kidney, increase in the concentration of pyruvate and lactate in blood, acidosis, hypoglycemia, convulsions, growth retardation |
| Pompe disease, glycogen storage disease type II | Lack of enzyme a-1,4-glucosidase | Abnormal accumulation of glycogene in the cells. Muscle weakness. Enlargement of heart, liver, kidney, spleen |
| Corey's disease, glycogenosis type III | Decreased activity of amilo-(1-6)-glycosidase and (or) glycogen branching enzyme | Residual time-branching dextrin is accumulated. Growth retardation, liver enlargement, muscular weakness, as a result of the accumulation of residual dextrin in muscles |
| Andersen's disease, glycogenosis type IV | Violation of glycogen branching enzyme activity, resulting in storage of abnormal glycogen | Enlarged liver, jaundice, cirrhosis, hypoglycemia |
| McArdle's disease, glycogenosis type V | Lack of muscle phosphorylase | Skeletal muscles are increased in volume and become very dense. Muscle weakness, muscle cramps, tachycardia at doing exercises |
| Hers' disease, glycogenosis type VI | Lack of hepatic enzyme phosphorylase | Enlargement of the liver, growth retardation, hyperlipemia, hyperglycemia |
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