linoleic-acid and Metabolism--Inborn-Errors

The treatment of children with inborn errors of metabolism (IEM) is mainly based on restricted dietary intake of protein-containing foods. However, dietary protein restriction may not only reduce amino acid intake, but may be associated with low intake of polyunsaturated fatty acids as well. This review focuses on the consequences of dietary restriction in IEM on the bioavailability of long-chain polyunsaturated fatty acids (LCPUFAs) and on the attempts to ameliorate these consequences. We were able to identify during a literature search 10 observational studies investigating LCPUFA status in patients with IEM and six randomized controlled trials (RCTs) reporting effect of LCPUFA supplementation to the diet of children with IEM. Decreased LCPUFA status, in particular decreased docosahexaenoic acid (DHA) status, has been found in patients suffering from IEM based on the evidence of observational studies. LCPUFA supplementation effectively improves DHA status without detectable adverse reactions. Further research should focus on functional outcomes of LCPUFA supplementation in children with IEM.

Topics: Adolescent; Adult; alpha-Linolenic Acid; Amino Acids; Arachidonic Acid; Biological Availability; Child; Child, Preschool; Diet; Diet, Protein-Restricted; Docosahexaenoic Acids; Fatty Acids, Unsaturated; Humans; Infant; Linoleic Acid; MEDLINE; Metabolism, Inborn Errors; Placebos; Randomized Controlled Trials as Topic

Previous studies have shown that phenylketonuric patients display a deficiency in long-chain polyunsaturated fatty acids. A study has now been performed on 13 cases (5 with methylmalonic acidaemia and 8 with urea cycle disorders) whose dietary treatment also implies a limitation in protein-rich food. Plasma and red-cell phospholipid fatty acid profiles were studied. The most relevant results were a lower percentage of docosahexaenoic acid in plasma and red-cell phospholipids (0.91% +/- 0.53% vs 2.88% +/- 1.17% and 2.07% +/- 0.92% vs 3.62% +/- 1.01% (p < 0.001)) and a lower percentage of arachidonic acid in plasma (5.22% +/- 2.02% vs 8.3% +/- 2.11% (p < 0.001)). A long-chain polyunsaturated acid deficiency has also been confirmed in this group of metabolic patients and a dietary supplement is recommended since this population is subject to a special risk factor with regard to adequate psychomotor development. By extrapolating these data to the general population, the possibility can be inferred that long-chain polyunsaturated fatty acids are semi-essential in infant nutrition far beyond the breast-feeding period.

Topics: alpha-Linolenic Acid; Amino Acid Metabolism, Inborn Errors; Arachidonic Acid; Child; Child, Preschool; Citrulline; Diet, Protein-Restricted; Docosahexaenoic Acids; Fatty Acids, Monounsaturated; Fatty Acids, Unsaturated; Humans; Infant; Infant, Newborn; Linoleic Acid; Metabolism, Inborn Errors; Methylmalonic Acid; Myristic Acid; Ornithine Carbamoyltransferase Deficiency Disease; Phospholipids

The purpose of the study was to compare the polyunsaturated fatty acid (PUFA) status in patients with X-linked adrenoleukodystrophy or adrenomyeloneuropathy (X-ALD/AMN) with that in disorders of peroxisome biogenesis (PB). Total fatty acids and plasmalogens were quantified in plasma and red cells from 28 patients with X-ALD/AMN, 26 patients with generalized peroxisomal disorders, and 37 controls. Total fatty acid methyl esters and plasmalogen dimethyl acetals were obtained by direct transmethylation and separated by capillary column gas chromatography. The results confirm previous findings in that docosahexaenoic acid (DHA, 22:6n-3) was greatly decreased in both plasma and erythrocytes from patients with PB disorders. When nutritional conditions were adequate, patients with X-ALD/AMN had normal levels of DHA. A highly significant positive correlation was found between the levels of DHA and those of plasmalogens in peroxisomal patients. As in other tissues, the parent n-6 fatty acid, linoleic acid (LA, 18:2n-6) was significantly increased in red cells from PB patients, whereas arachidonic acid (20:4n-6) was virtually within normal limits. In clear contrast to red cells and other tissues, arachidonate was significantly lower in plasma from PB patients. The decrease in plasma arachidonate and the high tissue levels of LA suggest a defect of delta 6 desaturase and/or delta 5 desaturase in PB patients. The n-6 fatty acids were normal in X-ALD/AMN patients. The present data show that X-ALD/AMN patients do not have the profound PUFA alterations that PB patients have, at least in blood.

Topics: Adolescent; Adrenoleukodystrophy; Adult; Arachidonic Acid; Child; Child, Preschool; Docosahexaenoic Acids; Erythrocytes; Fatty Acids, Unsaturated; Humans; Infant; Linoleic Acid; Linoleic Acids; Metabolism, Inborn Errors; Methylation; Microbodies; Plasmalogens; X Chromosome

Topics: Child, Preschool; Dietary Fats; Female; Humans; Linoleic Acid; Linoleic Acids; Malonates; Metabolism, Inborn Errors; Methylmalonic Acid