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Dysfunction of the nervous system caused by hereditary metabolic disorders


Disorders of the nervous system in congenital metabolic disorders result from the influence of several factors:
• direct damage to nerve cells due to failure
any enzyme;
• accumulation of certain undigested metabolic products outside the cellular fluid;
• damage to other organs (eg, liver);
• damage to cerebral vessels.
Hereditary diseases caused by direct damage to nerve cells include diseases of accumulation arising from the defect of lysosomal enzymes. The defect of any one such enzyme disrupts the intracellular metabolism of the corresponding macromolecules that accumulate inside the cells and, when combined with other molecules, form pathological inclusions that change the structure of the cells (displacement of the nucleus, swelling of the cytoplasm). In some cases, a violation of the exchange of macromolecules causes the death of neurons, in others - pronounced changes in their specific functions.
Diseases of accumulation include lipi doses, mucopolysaccharidoses, generalized glycogenoses. An example of lipidosis can be Niemann-Pick disease, characterized by accumulation of sphingomyelin in the liver, spleen, in the gray and white matter of the brain. The accumulation of sphingomyelin molecules, the most important component of the membranes of nerve cells, is due to the deficiency of the sphingomyelinase enzyme. Neurological disorders in Niemann-Pick disease, which is inherited in an autosomal recessive manner, are already detected in the first year of life and are manifested by progressive dementia, disorders of the functions of the pyramidal tract, and hearing impairment. Usually, patients die before the age of 5 years.
Diseases of the accumulation of mucopolysaccharides (mucopolysaccharidoses) are caused by a defect in the enzyme involved in the catabolism of mucopolysaccharides, glycosaminoglycans and glycolipids. Undigested mucopolysaccharide molecules accumulate in skin cells, cartilage, cornea, blood vessels, and cerebral cortex cells. Diseases are characterized by various signs, including skeletal disorders and progressive mental disorders associated with the degeneration of cells in the cerebral cortex, meninges and cerebral vessels.
Inherited by autosomal recessive type.
Significant impairment of the functions of the nervous system is found in type II glycogenosis — generalized glycogenosis (Pompe disease), caused by a deficiency of the lysosomal glycogen-splitting enzyme a-1,4-glucosidase. In this disease, particles of uncleaved glycogen are found in liver cells, kidneys, skeletal muscles, heart muscle, and cells of the central nervous system. A significant amount of glycogen accumulates in the lysosomes of the dorsal root neurons, in the motor neurons of the spinal cord, as well as in glial cells and in the endothelium of the cerebral vessels. As a result, the most frequent neurological symptoms of this disease, which are inherited in an autosomal recessive manner, are movement disorders and progressive muscle weakness.
Damage to cells of the central nervous system can be caused by a hereditary disorder of amino acid metabolism. In classical phenylketonuria, a disease associated with the deficiency of the enzyme phenylalanine hydroxylase, the differentiation of neurons is disturbed, the development of the brain slows down, and severe mental disorders occur. The mechanism of neuronal damage in phenylketonuria is rather complicated. Violation of the conversion of phenylalanine to tyrosine leads to a significant increase in the content of phenylalanine in all body fluids, and therefore its conversion into phenylpyruvic acid, which has a direct toxic effect on nerve cells, is activated; high levels of phenylalanine in the brain disrupts transmembrane transport of other amino acids and glucose in neurons, which in turn disrupts the synthesis of protein and nucleic acids in them; the inhibition of the conversion of phenylalanine to tyrosine violates the synthesis of catecholamines in the brain (catecholamines are formed from tyrosine); high levels of phenylalanine inhibits the synthesis of brain cells of another neurotransmitter - serotonin from the amino acid tryptophan. After neuronal differentiation processes end, an increased level of phenylalanine does not affect the development of intelligence. Limiting phenylalanine intake for the first 10 years of life prevents brain damage.
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Dysfunction of the nervous system caused by hereditary metabolic disorders

  1. HEREDITARY DISEASE SUBSTANCES WITH DESTRUCTION OF THE NERVOUS SYSTEM
    Hereditary diseases associated with metabolic disorders, develop as a result of changes in genetic information. If the formation of a specific trait is presented as a reading of the hereditary code recorded on the TsNK, and its implementation through a complex chain of biochemical transformations, then the hereditary metabolic diseases can be considered as a peculiar genetically
  2. Metabolic disorders and physiological functions during hypoxia
    Disbolism and physiological functions caused by a lack of oxygen supply, progressing with the insufficiency or exhaustion of compensatory-adaptive reactions. Initially, metabolic disorders manifest themselves in a decrease in the synthesis of high-energy compounds and changes in carbohydrate metabolism. Glycolysis, glycogenolysis are activated, production of pyruvate and lactate increases;
  3. Violations of the main physiological functions and metabolism
    The nervous tissue is most sensitive to oxygen starvation. With the complete cessation of oxygen supply, signs of disturbance in the cerebral cortex are already detected after 2.5-3 minutes. In acute hypoxia, the first disorders (especially clearly manifested in its hypoxic form) are observed on the part of higher nervous activity (euphoria, emotional disorders, changes in handwriting and
  4. Disorder of sexual function associated with metabolic disorders (nutritional impotence)
    Etiology. Occurs in manufacturing bulls with protein overfeeding (the content in the diet is more than 50% of concentrated feed for the overall nutritional value), lack of carbohydrate in the diet (sugar-protein ratio less than 0.8: 1.0), vitamins (for 1 cu. less than 70 mg of carotene, 1500 IU of vitamin D and less than 40 mg of vitamin E), mineral substances (for 1 ke, calcium is less than 7 grams, phosphorus -
  5. VIOLATION OF THE FUNCTIONS OF THE VEGETATIVE NERVOUS SYSTEM
    The vegetative nervous system innervates the smooth muscles of all organs of the body, the exocrine and endocrine glands, the heart. It regulates such vital functions as respiration, blood circulation, digestion, metabolism, maintains a constant body temperature, regulates the functions associated with the continuation of the species. The autonomic nervous system is not subject to direct voluntary control, in
  6. VIOLATION OF THE FUNCTIONS OF THE VEGETATIVE NERVOUS SYSTEM
    Peristalsis of the large intestine was observed in all 87 patients (100%). Dysfunction of the urinary system was observed in all 87 patients -100%. Violation of thermoregulation was observed in all 87 patients -100%. Disturbance of the trophic function of the nervous system from dystrophic manifestations to bedsores always accompanies spinal injury. Dystrophic changes
  7. DISTURBANCE OF FUNCTIONS OF THE SOMATIC NERVOUS SYSTEM
    Paralysis and paresis of various localization, accompanying spinal injury with damage to the spinal cord, is one of the most urgent problems of modern medicine. An unsolved problem is tetraplegia. After the stage of spinal shock, prolonged paralysis, indicating damage to somatic nerve fibers, is replaced by a gradual restoration of function of the striated
  8. Therapeutic physical culture with impaired function of the central nervous system
    Some massage techniques and exercises that promote the relaxation of increased muscle tone. For proper psychomotor development, it is very important that the child’s muscle tone matches his age. It is necessary from the first months of life of the child to monitor the position of his body in the crib. In a healthy child, the position of the head and torso without asymmetry. In some children with impaired muscle tone
  9. INHERENTLY CONDITIONED FORMS OF MENTAL AND PHYSICAL DEVELOPMENT
    For many decades, the leading factors in the etiology of persistent deviations in mental and physical development were considered prenatal hazards, the pathology of childbirth, trauma, infection, and intoxication of an early age. Achievements in medical and biological sciences led to a radical revision of these ideas. Over the years, many hereditary diseases and syndromes have been discovered, and rightly now
  10. Hereditary disorders of amino acid metabolism (aminoacidopathy)
    The relevance of considering interstitial amino acid metabolism disorders is determined by the fact that this pathology is reflected, first of all, on the function of the nervous system and is one of the main causes of dementia. Knowledge of this pathology is necessary in the practice of neonatologists and genetic laboratories for the prevention and early correction of oligophrenia. Phenylpyruvic oligophrenia (synonym -
  11. Hereditary hemolytic anemia caused by the disturbance of the activity of red blood cell enzymes
    Fermentopathies or non-spherocytic hemolytic anemias are characterized by a hereditary decrease in activity or instability of erythrocyte enzymes. Inherited autosomal recessive or X-linked recessive type. The most severe hemolytic manifestations are observed, as a rule, in homozygous carriers with an almost complete absence of enzyme activity in
  12. Heart damage in metabolic disorders
    Metabolic disorders in the body always affect the course of metabolic processes in the myocardium, often causing a violation of its function and structure. In various diseases, one or several pathways of metabolism may be initially disturbed, which further necessarily affects the energy supply of the heart muscle. With some metabolic disorders in the interstitial myocardial tissue and in
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