ascorbic-acid and Intellectual-Disability

Tyrosinemia II is caused by a deficiency of hepatic tyrosine aminotransferase. With the deficiency of this key enzyme of tyrosine catabolism there is an increase in plasma tyrosine and then an increase in tyrosine metabolites in the urine. The increased plasma tyrosine causes tyrosine to crystallize in the cornea, producing corneal ulcerations and sometimes proliferation of corneal epithelium. In the epidermis of the palms and soles, tyrosine leads to erosions, crusting, and then hyperkeratosis. The human disease is due to an autosomal recessive gene, and similar genetic diseases have been found in mink and in dogs. A nutritional model for the disease, in which a high-tyrosine low-protein diet is fed to rats, produces almost identical features. The features of this disorder and some of the implications of this disease for the study of other genetic diseases is discussed in this review.

Topics: Adolescent; Amino Acid Metabolism, Inborn Errors; Animals; Ascorbic Acid; Child; Child, Preschool; Eye; Female; Genetic Carrier Screening; History, 20th Century; Humans; Infant; Infant, Newborn; Intellectual Disability; Isomerism; Isotretinoin; Male; Pyridoxine; Rats; Skin; Tretinoin; Tyrosine; Tyrosine Transaminase

Topics: Ascorbic Acid; Cytochrome-B(5) Reductase; Erythrocytes; Glutathione; Hemoglobins; Humans; Intellectual Disability; Methemoglobin; Methemoglobinemia; Metmyoglobin; NAD; NADP; Oxidation-Reduction

Topics: Adult; Ascorbic Acid; Humans; Intellectual Disability; Male; Middle Aged; Placebos; Substance Withdrawal Syndrome; Tranquilizing Agents

Topics: Adolescent; Adult; Ascorbic Acid; Child; Diet; Female; Hemoglobinometry; Humans; Intellectual Disability; Male; Middle Aged; Periodontal Diseases; Statistics as Topic

Coatomer complexes function in the sorting and trafficking of proteins between subcellular organelles. Pathogenic variants in coatomer subunits or associated factors have been reported in multi-systemic disorders, i.e., coatopathies, that can affect the skeletal and central nervous systems. We have identified loss-of-function variants in COPB2, a component of the coatomer complex I (COPI), in individuals presenting with osteoporosis, fractures, and developmental delay of variable severity. Electron microscopy of COPB2-deficient subjects' fibroblasts showed dilated endoplasmic reticulum (ER) with granular material, prominent rough ER, and vacuoles, consistent with an intracellular trafficking defect. We studied the effect of COPB2 deficiency on collagen trafficking because of the critical role of collagen secretion in bone biology. COPB2 siRNA-treated fibroblasts showed delayed collagen secretion with retention of type I collagen in the ER and Golgi and altered distribution of Golgi markers. copb2-null zebrafish embryos showed retention of type II collagen, disorganization of the ER and Golgi, and early larval lethality. Copb2

Topics: Animals; Ascorbic Acid; Bone and Bones; Brain; Child; Child, Preschool; Coat Protein Complex I; Coatomer Protein; Collagen Type I; Developmental Disabilities; Embryo, Nonmammalian; Endoplasmic Reticulum; Female; Fibroblasts; Gene Expression Regulation, Developmental; Golgi Apparatus; Haploinsufficiency; Humans; Intellectual Disability; Male; Mice; Osteoporosis; RNA, Small Interfering; Severity of Illness Index; Zebrafish

As part of a longitudinal study aimed at assessing the dietary intakes and nutritional status of a group of long-stay mentally handicapped subjects, 15 women of menstruating age were considered for a substudy to assess the influence of intake levels of dietary iron, energy, tea, coffee and vitamin C on their iron status. The assessment comprised a week-long weighed dietary survey and the measurement of a number of haematological indices that included serum ferritin concentration. Information on duration of menses was also collected and included in the assessment. Two-fifths of the subjects assessed had a serum ferritin concentration less than 12 micrograms/l indicating iron deficiency, including one who was considered anaemic as suggested by a haemoglobin level less than 12 g/dl. Duration of menses showed a negative significant correlation with serum ferritin concentration. The mean iron intake in the group was 9.5 +/- 1.5 mg/day. Energy intakes were low and positively correlated with iron intake. Although serum ferritin showed no correlation with iron intake, it showed significant negative correlations with the daily and meal-time intakes of tea and a significant positive correlation with the meal-time intakes of vitamin C. The six iron-depleted subjects were assessed as a separate group (Group I) in comparison with the other nine subjects who had a serum ferritin concentration greater than 12 micrograms/l. The results of this assessment showed that, while there were no significant differences in duration of menses or the mean daily intakes of iron and energy between the two groups. Group I subjects had significantly higher daily and meal-time intakes of tea and significantly lower meal-time intakes of vitamin C compared to Group II subjects. The study provides some evidence suggestive of an association between the iron deficiency states observed and tea intake in adversely affecting iron status, particularly in the absence of adequate meal-time intakes of vitamin C. The findings from the study also suggest that long-stay mentally handicapped women of menstruating age, in addition to their handicap and dependency states which may often predispose them to a low dietary intake, are at particular risk of iron deficiency.

Topics: Adult; Anemia, Hypochromic; Ascorbic Acid; Coffee; Diet Surveys; Energy Metabolism; Female; Ferritins; Humans; Intellectual Disability; Longitudinal Studies; Menstruation; Nursing Homes; Nutrition Assessment; Nutritional Status; Prevalence; Tea; United Kingdom

As fracture is known to occur more easily in severely handicapped children (SHC), bone mineral content, serum zinc level and serum vitamin C level were determined in 65 SHC. These parameters were found to be greatly reduced in all patients. The decreases in zinc and vitamin C in the serum appeared to be associated with that in bone mineral content. Supplements of zinc and vitamin C may be important to decrease the chance of fracture due to diminished bone mineral content in SHC.

Topics: Adolescent; Adult; Ascorbic Acid; Bone Density; Disabled Persons; Female; Fractures, Bone; Humans; Intellectual Disability; Male; Zinc

Preliminary data of a postmortem brain study in a single case with Rett syndrome compared to a single control case showed a severe reduction of ascorbic acid and reduced glutathione in most brain regions studied. These findings suggest a secondary disturbance of ascorbic acid and glutathione metabolism in the Rett syndrome.

Topics: Ascorbic Acid; Brain Chemistry; Brain Diseases; Child; Female; Glutathione; Humans; Intellectual Disability; Syndrome

The recent upsurge in megavitamin therapy raises questions about the role of vitamin deficiencies and dependencies in mental health. With this in mind, the plasma levels of folic acid, ascorbic acid, pyridoxine, and riboflavin were studied in approximately 125 children admitted to a child psychiatric unit. There were no apparent decreased levels of vitamins in these children in terms of their age, race, or psychiatric diagnosis. It is postulated that vitamin deficiencies per se cannot be proposed as etiological factors in any of the psychiatric deficits represented. Megavitamin therapy, if successful, is not effective due to crrection of vitamin deficiencies as opposed to vitamin dependencies and may be due to the metabolic onus and consequent effects of such heavy doses of vitamins.

Topics: Adolescent; Affective Symptoms; Ascorbic Acid; Autistic Disorder; Child; Child Behavior Disorders; Child, Preschool; Folic Acid; Humans; Intellectual Disability; Male; Orthomolecular Therapy; Psychotic Disorders; Pyridoxine; Riboflavin; Schizophrenia

Ascorbic acid status of thirty-nine white children with developmental disabilities, ages three to nineteen years, is reported. Mean daily ascorbic acid intakes were calculated from three-day food records. Biochemical assessment consisted of fasting serum levels and a 6-hr. load test. Nine children served as a control group for the load test only. Mean dietary intakes for the vitamin were 204 per cent of the allowance. The mean serum ascorbic acid value was 1.3 mg. per deciliter. Only two children had levels at the unacceptable deficient level. Following load tests, ten children were identified as low excretors (less than 17 per cent), nine were moderate excretors (17 to 23 per cent), and the rest were high excretors (above 23 per cent). All of the normal children were high excretors. Two of three children with low ascorbic acid intakes (below 66 per cent of the recommended allowance) were verified as deficient by their fasting serum levels and urinary recovery after a load.

Topics: Adolescent; Adult; Ascorbic Acid; Ascorbic Acid Deficiency; Child; Child, Preschool; Female; Humans; Intellectual Disability; Male; Mental Disorders; Neurocognitive Disorders; Neurotic Disorders; Nutritional Requirements

The author conducted a study of the tyrosine balance and the urine excretion of its metabolites: paraoxyphenylpyruvic and homogentistic acid in 39 oligophrenic patients of a nontypical and of 90 with an exogenous genesis. In exogenic forms of oligophrenia the oxidation of tyrosine was characterized by hypertyrosinemia, hypertyrosinuria, a drop of paraoxyphenylpyruvic acid excretion. In genotypical oligophrenia the most typical were high indices of tyrosinemia, tyrosinuria, excretion of paraphenylpyruvic acid and homogentistic acid.

Topics: Adolescent; Ascorbic Acid; Child; Female; Homogentisic Acid; Humans; Intellectual Disability; Male; Phenylpyruvic Acids; Syndrome; Tyrosine

Topics: Adolescent; Amino Acid Metabolism, Inborn Errors; Amino Acids; Ascorbic Acid; Cataract; Female; Humans; Intellectual Disability; Mandelic Acids; Methionine; Mixed Function Oxygenases; Phenylacetates; Phenylpyruvic Acids; Tyrosine

Topics: Ascorbic Acid; Body Weight; Child, Preschool; Diet Therapy; Humans; Intellectual Disability; Male; Metabolism, Inborn Errors; Nervous System Diseases; Obsessive-Compulsive Disorder; Pedigree; Self Mutilation; Uric Acid

Topics: Ascorbic Acid; Biological Transport; Blood-Brain Barrier; Cerebrospinal Fluid Proteins; Humans; Intellectual Disability; Nucleosides; Nucleotides; Schizophrenia; Spectrophotometry

Topics: Ascorbic Acid; Carbohydrate Metabolism; Cholesterol; Disabled Persons; Female; Health Facilities; Humans; Intellectual Disability; Lipid Metabolism

Topics: Ascorbic Acid; Cerebral Palsy; Child; Disabled Children; Folic Acid; Gingivitis; Humans; Infant; Intellectual Disability; Vitamin A; Vitamin B Complex; Vitamin K; Vitamins