Vitamin neurological disease

A glance at vitamins in clinical medicine opens a wide panorama with challenging aspects in hepatic conditions, in oxalosis and calculus disease, in obscure, but widely spread neurological diseases, and in many others astute clinical observations, combined with knowledge of the function and mechanism of vitamin action, will bring vitamin analysis into the picture as a useful tool. 

Monekosso GL, Wilson J. 1966. Plasma thiocyanate and vitamin B12 in Nigerian patients with degenerative neurological disease. Lancet 14 1062-1064. 

Substantial evidence indicates that high plasma levels of lipoprotein remnants and LDL are atherogenic, while high levels of HDL are atheroprotective. Therefore, the class of lipoproteins that is increased or decreased will determine the clinical feature of a patient. Besides the influence on atherosclerosis, high levels of chylomicrons lead to acute pancreatitis, while markedly decreased levels of VLDL and LDL lead to retinal and neurologic disease, probably due to vitamin E deficiency. 

Ascorbic acid has been implicated in many neurological diseases. There is a strong inverse relation between serum vitamin C concentration and stroke incidence... 

Methionine metabolism is very dependent on both FH4 and vitamin B12. Homocysteine is derived from methionine metabolism and can be converted back into methionine by using both methyl-FH4 and vitamin B12. This is the only reaction in which methyl-FH4 can donate the methyl group. If the enzyme that catalyzes this reaction is defective, or if vitamin B12 or FH4 levels are insufficient, homocysteine will accumulate. Elevated homocysteine levels have been linked to cardiovascular and neurologic disease. A vitamin B12 deficiency can be brought about by the lack of intrinsic factor, a gastric protein required for the absorption of dietary B12. A consequence of vitamin B12 deficiency is the accumulation of methyl-FH4 and a decrease in other folate derivatives. This is known as the... 

Wernicke Korsakoff syndrome (WKS) is the neurological disorder most clearly linked to thiamine deficiency in humans. WK develops in a subset of chronic alcoholics, who are vitamin deficient because so many calories are consumed as alcohol instead of normal diet, and a diet rich in carbohydrates increases the metabolic demand for thiamine. Thiamine dependent enzymes were diminished in the brains of patients who died with WKS, but not in alcoholic controls (Butterworth et al., 1993). Transketolase in fibroblasts from those patients who develop WKS syndrome binds TPP more avidly than the control lines. The Km was nearly ten times higher in patients with WKS. Thus, these patients have an abnormahty of transketolase that would be clinically unimportant if the diet was adequate (Blass and Gibson, 1977, 1979). The latter demonstrate a predisposing biochemical mutation to a neurological diseases that is only revealed by inadequate diet. 

In diagnoses of some rare conditions, such as bile acid synthetic defects, MS can also be utilized. Nowadays it is possible to screen and rapidly diagnose potential or real inborn errors in bile acid synthesis from urinary bile acid analysis by means of MS. Specific mutations in the genes that encode the enzymes responsible for bile acid synthesis can be identified by molecular techniques. Of the seven known genetic defects that cause progressive cholestatic Uver disease, syndromes of fat-soluble vitamin malabsorption, and neurological disease, six have been properly characterized [16]. 

Methionine synthase deficiency (cobalamin-E disease) produces homocystinuria without methylmalonic aciduria 677 Cobalamin-c disease remethylation of homocysteine to methionine also requires an activated form of vitamin B12 677 Hereditary folate malabsorption presents with megaloblastic anemia, seizures and neurological deterioration 678... 

Cushing s disease, hyperparathyroidism, hyperthyroidism, hypothyroidism, hypoglycemia, hyponatremia, hyperkalemia, pheochromocytoma, vitamin B12 or folate deficiencies Neurologic... 

Strict vegetarian diet or after diseases affecting cobalamin absorption. The main effects of vitamin deficiency are pernicious anemia, macrocytosis, and neurological problems. A particularity of this vitamin is that it can be stored especially in the liver and kidneys. 

Severe thiamine vitamin Bf) deficiency results in beriberi. The symptoms can include growth retardation, muscular weakness, apathy, edema, and heart failure. Neurological symptoms, such as personality changes and mental deterioration, also may be present in severe cases. Because of the role played by thiamine in metabolic processes in all cells, a mild deficiency may occur when energy needs are increased. Since thiamine is widely distributed in food, beriberi is rare except in communities existing on a single staple cereal food. The disease does occur with some frequency in alcoholics, whose poor diet may lead to an inadequate daily intake of thiamine. 

In >crnicious anemia, the hone marrow fails to produce mature erythrocytes as a result of defective cell division, a consequence of impaired DNA synthesis which requires vitamin BI If the disease goes unlreaietl, extensive neurological damage, c.g.. irreversible degeneration of the spinal cord by deinyeliniralinn. may occur hccausc of faulty fatly acid metabolism. 

Vitamin B12 is available in pure form for oral administration or in combination with other vitamins and minerals for oral or parenteral administration. The choice of a preparation always must be made with recognition of the cause of the deficiency. Although oral preparations may be used to supplement deficient diets, they are of relatively little value in the treatment of patients with deficiency of intrinsic factor or ileal disease. Even though small amounts of vitamin B12 may be absorbed by simple diffusion, the oral route of administration cannot be relied upon for effective therapy in the patient with a marked deficiency of vitamin B12 and abnormal hematopoiesis or neurological deficits. Therefore, the preparation of choice for treatment of a vitamin B12-deficiency state is cyanocobal-amin, and it should be administered by intramuscular or deep subcutaneous injection. 

Deficiencies of vitamin B12 can result from either low dietary levels or, more commonly, from poor absorption of the vitamin due to the failure of gastric parietal cells to produce intrinsic factor (as in pernicious anemia) or to a loss of activity of the receptor needed for intestinal uptake of the vitamin.5 Nonspecific malabsorption syndromes or gastric resection can also cause vitamin B12 deficiency. The vitamin may be administered orally (for dietary deficiencies), or intramuscularly or deep subcutaneously (for pernicious anemia). [Note Folic acid administration alone reverses the hematologic abnormality and thus masks the B12 deficiency, which can then proceed to severe neurologic dysfunction and disease. Therefore, megaloblastic anemia should not be treated with folic acid alone, but rather with a combination of folate and vitamin B12.] Therapy must be continued for the remainder of the life of a patient suffering from pernicious anemia. There are no known adverse effects of this vitamin. 

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