Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Children deficient in vitamin E have various neurologic symptoms. 2 cases representing different mechanisms of this vitamin deficiency are reported. A 15-year-old boy with fat malabsorption due to cystic fibrosis who was diagnosed as being vitamin E deficient (< 0.5 mg/l), had typical neuropathies. On the other hand, a 12-year-old Beduin girl had isolated vitamin E deficiency, as well as neurological symptoms suggestive of Friedrich's ataxia. Vitamin E supplementation by intramuscular injection in the first case and per os in the second led to significant improvement in neurological symptoms.
 ...
PMID:[Neurological symptoms associated with vitamin E deficiency]. 868 50

The objective of this study was to examine differences in plasma alpha-tocopherol concentrations after oral administration of pharmacologic doses of vitamin E to normal healthy subjects as RRR-alpha-tocopheryl glycol 1000 succinate (TPGS; water-miscible form) and RRR-alpha-tocopheryl acetate (TA; fat-soluble form). The study was designed to evaluate the administration of three different single doses and multiple doses for 4 wk with both preparations. Administration of 400 IU (269 mg), 800 IU (537 mg), and 1200 IU (807 mg) TPGS as a single dose resulted in slight elevation of plasma alpha-tocopherol concentrations. Administration of multiple daily doses at all three amounts of TPGS for 28 consecutive days resulted in a slight elevation of plasma alpha-to-copherol concentrations. A significant increase in plasma alpha-to-copherol concentrations was observed after ingestion of a single dose or equivalent multiple doses of TA at all three doses. As reported in the literature, in cases of cholestasis and other forms of lipid malabsorption, oral administration of TPGS is the treatment of choice. It appears that for normal adults and patients with normal lipid absorption, fat-soluble forms of vitamin E are preferable for therapeutic and prophylactic uses.
 ...
PMID:Plasma alpha-tocopherol concentrations after supplementation with water- and fat-soluble vitamin E. 878 Mar 42

Vitamin A is an essential nutrient for epithelial cell maintenance and repair, and it is known that infectious stresses may depress plasma vitamin A concentrations. Patients with cystic fibrosis are at risk for vitamin A deficiency because of fat malabsorption as well as for the inflammatory stresses of pulmonary exacerbations of their underlying disease. We therefore hypothesized that acute pulmonary exacerbations of CF would depress plasma retinol concentrations, and that these concentrations would return to baseline values when clinical symptoms improved. We prospectively studied 35 CF patients (mean age: 24.2 y) consecutively admitted with pulmonary exacerbations. Plasma retinol, vitamin E, retinol binding protein (RBP), and C-reactive protein (CRP) concentrations were measured on hospital admission and discharge. Dietary intake was measured by using a semiquantitative food-frequency questionnaire. Regression analysis was used to identify significant clinical and laboratory correlates of retinol concentrations. On admission, mean (+/- SD) concentrations of plasma retinol were 1.14 +/- 0.5 mumol/L compared with 1.70 +/- 0.6 mumol/L on discharge (P = 0.0001). Of 35 subjects, 8 (22.9%) had plasma retinol concentrations considered to be in the deficient range (< 0.70 mumol/L). Concurrently, mean concentrations of plasma RBP increased during hospital admission (from 1.46 to 2.24 mumol/L, P = 0.003), and the mean CRP concentration declined (from 25.7 to 9.8 mg/L, P = 0.002). Significant positive correlations were found between plasma retinol concentrations at admission and age, weight, body mass index, triceps-skinfold-thickness percentile, midupper arm circumference percentile, plasma vitamin E, and RBP concentration, thus suggesting that better-nourished patients had more optimal vitamin A status. At admission, plasma retinol concentrations were negatively correlated with maximum body temperature and CRP concentrations, which indicated that the body's acute-phase response was associated with the depression in retinol concentrations. We conclude that plasma retinol concentrations are depressed in acute pulmonary exacerbations of cystic fibrosis, and that concentrations considered to be in the deficient range are common. Vitamin A metabolism during acute inflammatory stress deserves further study.
 ...
PMID:Vitamin A status in acute exacerbations of cystic fibrosis. 883 11

How much vitamin E is enough? An established use of supplemental vitamin E in humans is in the prevention and therapy of deficiency symptoms. The cause of vitamin E deficiency, characterized by peripheral neuropathy and ataxia, is usually malabsorption-a result of fat malabsorption or genetic abnormalities in lipoprotein metabolism. Genetic abnormalities in the hepatic alpha-tocopherol transfer protein also cause vitamin E deficiency-defects in this protein cause an impairment in plasma vitamin E transport. Impaired delivery of vitamin E to tissues, thereby, results in deficiency symptoms. Also discussed is the use of supplemental vitamin E in chronic diseases such as ischemic heart disease, atherosclerosis, diabetes, cataracts, Parkinson's disease, Alzheimer's disease, and impared immune function, as well as in subjects receiving total parenterol nutrition. In healthy individuals, a daily intake of about 15-30 mg of alpha-tocopherol is recommended to obtain "optimal plasma alpha-tocopherol concentrations" (30 microM or greater).
 ...
PMID:Vitamin E in humans: demand and delivery. 883 30

We describe 4 siblings of a consanguineous Bedouin family with Friedreich ataxia phenotype in whom low serum vitamin E levels without other indicators of fat malabsorption were detected. Although age of onset and some of the clinical features were alike in all 4 patients, the electrophysiological parameters were markedly abnormal in 2, but normal in the other 2. Erythrocytes revealed both membranous and intracellular evidence of oxidative damage. The mutations described in other families with ataxia with isolated vitamin E deficiency were not detectable, nor was an abnormal single-stranded conformation polymorphism pattern apparent in the three exons at the 3' region of the gene. Vitamin E administration in pharmacological doses improved the neurological condition in 2 patients and also corrected some of the patients' erythrocyte cell abnormalities. The finding of vitamin E deficiency in other cases of Friedreich ataxia phenotype may allow treatment at an early stage of the disease, when large dose Vitamin E therapy may reverse the neurological lesions.
 ...
PMID:Ataxia with isolated vitamin E deficiency in four siblings. 897 36

Vitamin E is one of the most important lipid-soluble antioxidant nutrients. Severe vitamin E deficiency can have a profound effect on the central nervous system. Cystic fibrosis, chronic cholestatic liver disease, abetalipoproteinemia, short bowel syndrome, isolated vitamin E deficiency syndrome and other malabsorption syndromes all may cause varying degrees of neurologic deficits due to related vitamin deficiencies. The classic abnormalities in vitamin E deficiency progress from hyporeflexia, ataxia, limitations in upward gaze and strabismus to long-tract defects, profound muscle weakness and visual field constriction. Patients with severe, prolonged deficiency may develop complete blindness, dementia and cardiac arrhythmias. Treatment must be tailored to the underlying cause of vitamin E deficiency and may include oral or parenteral vitamin supplementation. The more advanced the deficits, the more limited the response to therapy. Therefore, a good neurologic examination and periodic serum vitamin E levels are essential in patients at risk of vitamin E deficiency.
 ...
PMID:Neurologic findings in vitamin E deficiency. 901 78

Oxygen free radicals have been implicated as mediators of tissue injury in a variety of diseases. We investigated the role of oxidative injury and oxygen free radical scavengers in liver cell injury associated with obstructive jaundice in Wistar rats. Bile duct ligation for 4 or 7 days led to a decrease in both vitamin E and A in the plasma and liver of male Wistar rats, indicating the malabsorption of lipid-soluble vitamins. Serum bilirubin, alkaline phosphatase and gamma-glutamyl transpeptidase activities were increased in the bile-duct-ligated rats. Furthermore, marked increases in lipid peroxide and oxidized glutathione levels indicated cholestatic liver injury. The antioxidant defense system was impaired, as shown by decreases in reduced glutathione and in the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase. Moreover, these high lipid peroxide levels and low levels of antioxidants correlated with the severity of jaundice. After releasing the bile duct ligation, levels of bilirubin, lipid peroxide and oxidized glutathione declined, while the levels of vitamin E and A, reduced glutathione, and the activities of GSH-Px increased, indicating an improvement in liver function. These findings suggest that lipid peroxidation is associated with the pathogenesis of liver damage in animals with bile duct ligation. Meanwhile, free oxygen radical scavengers are reduced in the bile-duct-ligated rats, thereby increasing the susceptibility of the liver to injury by oxygen-derived free radicals.
 ...
PMID:Biochemical events associated with ligation of the common bile duct in Wistar rats. 903 77

The somatosensory evoked potentials from the lower extremities were measured postoperatively in 15 patients with biliary atresia to investigate whether they were free of neurologic dysfunction. Because long-standing cholestasis causes progressive neuropathy due to malabsorption of vitamin E, the serum vitamin E, D, and A levels were also examined to evaluate the fat-soluble vitamin status. The cerebral evoked potentials to posterior tibial nerve stimulation were recorded in all 15 patients as well as in 45 controls, but spinal evoked potentials examined at the level of the cauda equina could not be recorded in five patients more than 8 years of age with long-standing icterus. The remaining 10 patients exhibited spinal evoked potentials as observed in the controls, but the mean neural conduction velocity at the cauda equina was significantly lower than that of the 45 controls (42.0 +/- 5.1 m/s vs 52.3 +/- 6.8 m/s, P = .0002). The serum vitamin E, D, and A levels were within the normal range in 13, 9, and 1 of 15 patients, respectively. These results suggest that the patients with long-term follow-up are still at risk of developing neural disturbances even with normal serum vitamin E status.
 ...
PMID:Evoked potential abnormalities in postoperative patients with biliary atresia. 916 10

Reaction of 5a-bromo-alpha-tocopherol with ascorbic acid produces 5a-tocopheryl ascorbate which is designated "vitamin CE." This novel tocopherol derivative represents an interesting prodrug form of alpha-tocopherol (vitamin E) that is stable under acidic conditions, but regenerates finely dispersed vitamin E in basic media. The reaction mechanism of the base-induced decomposition of vitamin CE involves elimination of ascorbate and production of an ortho-quinone methide intermediate that oxidizes ascorbate, and is reduced to vitamin E. Kinetic experiments showed reaction to proceed in the pH range of 8 to 11 under physiological conditions. Tissue culture measurements demonstrated that vitamin E generated from the novel derivative is absorbed at much higher rates than conventional preparations and can even be absorbed under simulated conditions of malabsorption where there is no uptake of conventional vitamin E medications.
 ...
PMID:"Vitamin CE," a novel prodrug form of vitamin E. 921 11

A 24-year-old male, who suffered since childhood from a progressive form of ataxia associated with peripheral neuropathy, was found severely deficient in serum vitamin E. He walked with bilateral aid and presented severe dysmetria of the limbs and dysarthric speech; muscular strength and trophism were slightly diminished in the distal muscles of four limbs and there was hypotonia of the arms; he presented absent deep tendon reflexes, bilateral Babinski's sign, reduced proprioception at four limbs, pes cavus and fasciculations of the tongue. Intestinal fat malabsorption and other gastrointestinal or haematological conditions associated with deficiency of this vitamin were ruled out. In this patient, after 2 years of a daily supplement of high doses of vitamin E, a further progression of the disease was not observed and, moreover, the neurophysiological characteristics of his neuropathy appeared clearly improved. A longitudinal evaluation of serum vitamin E levels showed values in the normal range after 13 months of therapy. The patient had molecular genetic analysis of chromosome 8 and was found homozygous for the unusual mutation 513insTT in the alpha-tocopherol transfer protein gene.
 ...
PMID:Supplemental therapy in isolated vitamin E deficiency improves the peripheral neuropathy and prevents the progression of ataxia. 958 54


<< Previous 1 2 3 4 5 6 7 8 9 10