Biochemical effects of supplemented long-chain polyunsaturated fatty acids in hyperphenylalaninemia.

Hyperphenylalaninemic (HPA) children display low levels of long-chain polyunsaturated fatty acids (LCPUFA), particularly docosahexaenoic acid (DHA), in circulating lipids and erythrocytes. We have investigated the effects on the blood fatty acid status and lipid picture of a balanced supplementation with LCPUFA in HPA children through a double-blind, placebo-controlled trial. A total of 20 well-controlled HPA, school-age children were randomized to receive through a 12-month trial fat capsules supplying either 26% fatty acid as LCPUFA (including 4.6%gamma -linolenic acid, 7.4% arachidonic acid, AA, 5.5% eicosapentaenoic acid and 8% DHA) or placebo (olive oil). The study supplementation was administered in order to provide 0.3-0.5% of the individual daily energy requirements as LCPUFA. Reference data were obtained from healthy children of comparable age. Among HPA children (whose DHA status was poor at baseline), those supplemented with LCPUFA showed an increase of around 100% in the baseline DHA levels in plasma phospholipids and erythrocytes. No changes of AA levels were observed. Blood lipid levels did not significantly change. A balanced supplementation with LCPUFA in treated HPA children may improve the DHA status without adversely affecting the AA status.

Effects of long-chain polyunsaturated fatty acid supplementation on fatty acid status and visual function in treated children with hyperphenylalaninemia.

BACKGROUND: Children with phenylalanine-hydroxylase deficiency (type-I hyperphenylalaninemia, HPA) follow a low-phenylalanine diet, severely restricted in animal foods and long-chain polyunsaturated fatty acids (LCPUFA). Consequently, they have a poor LCPUFA status, particularly for docosahexaenoic acid (DHA). DHA is relevant to visual and neural development. OBJECTIVE: To investigate the effects of a 12-month supplementation with LCPUFA in a double-blind, placebo-controlled trial in treated children with HPA. STUDY DESIGN: Twenty children with well-controlled HPA were randomly allocated to receive either a fat supplement (supplying 26% as fatty acids including DHA, 8%) or a placebo. The fatty acid composition of erythrocyte lipids and the visual evoked potentials were measured at baseline and after 12 months of supplementation. Reference data were obtained from healthy children of comparable age. RESULTS: At baseline children with HPA had a poorer DHA status and prolonged P100 wave latencies than the reference group. At the end of the trial the LCPUFA group showed a significant increase in DHA levels of erythrocyte lipids. In the LCPUFA group P100 wave latency decreased and was negatively associated with the DHA changes. CONCLUSIONS: A balanced dietary supplementation with LCPUFA in children with HPA is associated with an increase of the DHA pool and improved visual function.

Low levels of linoleic acid in plasma total lipids of HIV-1 seropositive children.

OBJECTIVE: To assess the plasma fatty acid status of a group of well-nourished children with the human immunodeficiency virus type-1 (HIV-1) and how this relates to the blood total CD4+ lymphocyte count. SUBJECTS: Fourteen HIV-1 seropositive children at various stages of disease and with adequate growth indices were assessed and compared to a control group of 30 healthy children. RESULTS: The concentrations (mg/dL) of plasma total fatty acids were not different between the two groups. HIV-1 seropositive children presented lower levels of 18-C essential polyunsaturated fatty acids (PUFA: linoleic acid, LA, and alpha-linolenic acid) and higher levels of their 20-C long-chain derivatives (di-homo-gamma-linolenic acid, arachidonic acid, AA, and eicosapentaenoic acid) and docosahexaenoic acid in their plasma total lipids. The lowest plasma LA levels were observed in the subgroup of patients with more advanced stages of disease. In bivariate analyses the plasma LA levels related positively (Spearman r = 0.50, p = 0.06), while the LA/AA ratio related negatively (Spearman r = -0.51, p = 0.06), to the total CD4+ count. CONCLUSIONS: Childhood HIV-1 infection is associated with changes in plasma fatty acid profile suggestive of an increased PUFA turnover. Decreased levels of LA (together with higher plasma AA levels) appear to be associated with more advanced clinical and biochemical stages of disease.

Developmental quotient at 24 months and fatty acid composition of diet in early infancy: a follow up study.

AIM: A follow up study of developmental quotient (DQ) at 24 months of toddlers whose diets in early infancy differed in fatty acid composition, and in whom an association between diet and DQ was observed at 4 months. METHODS: 81 toddlers were distributed among three groups according to early type of diets standard infant formula (SFo, n = 30); long chain polyunsaturated fatty acid (LC-PUFA) enriched formula (LCPFo, n = 26); human milk (HM, n = 25). DQ at 24 months was assessed by Brunet-Léxine's psychomotor developmental test. A subgroup (n = 20; SFo 8; LCPFo 6; HM 6) was tested for erythrocyte phosphatidyicholine and phosphatidylethanolamine. RESULTS: No DQ differences were found by analysis of variance. Neither DQ nor erythrocyte docosahexaenoic acid at 4 months were predictors of DQ scores at 24 months. Phosphatidylcholine arachidonic and docosahexaenoic acid correlated positively, and phosphatidylcholine linoleic acid and phosphatidylethanolamine eicosapentaenoic acid negatively, with DQ. Multiple regression analysis including these variables explained 52% of inter-individual DQ variance. A strong association was found between the erythrocyte phosphatidylcholine arachidonic/ linoleic acid ratio and DQ (r = 0.75; p = 0.0001). CONCLUSIONS: The diet/DQ association found at 4 months was not predictive of DQ scores at 24 months. Irrespective of dietary or genetic factors, there appears to be a strong correlation between the LC-PUFA composition of the red cell membrane and higher neurodevelopmental performance.

The effects of n-3 and n-6 polyunsaturated fatty acids on plasma lipids and fatty acids of treated phenylketonuric children.

Dietary-treated phenylketonuric patients (PKUs) display low levels of long-chain polyunsaturated fatty acids (PUFA) in plasma lipids. In a 6-month clinical trial we observed a decrease of triglycerides and an increase of n-3 long-chain PUFA in plasma of PKUs supplemented with fish oil, while no major differences in respect to the baseline values were found in a group supplemented with blackcurrant oil. A more complete source of long-chain PUFA of both the n-6 and n-3 series should be investigated for dietary supplementation of PKU patients.

[Fatty acids: their biochemical and functional classification]. / Gli acidi grassi: classificazione biochimica e funzionale.

Fatty acids (FA) constitute the main component of phospholipids, triglycerides and cholesterol esters. FA are acidic, monocarboxylic linear chains of variable length: short-chain FA (2-4 carbon atoms), medium-chain FA (6-12 carbon atoms), long-chain FA (14-18 carbon atoms), very long-chain FA (derived from parental 18-carbon molecules). They can be further subdivided into saturated (no double bond), monounsaturated (one double bond) and polyunsaturated (two or more double bonds). They are all involved in energetic, metabolic and structural activities. Short-chain FA act as growth factors; medium chain FA are readily available as energy source; saturated long-chain FA constitute a source of energy but may be implicated in the development of the atherosclerotic process; unsaturated long-chain FA include oleic acid and the essential fatty acids (linoleate and linolenate), and are all implicated in fundamental metabolic processes; very-long chain FA are the most characteristic molecules in biologic membranes. From recent works it is clearly established that the physiological role of FA depends on the chain length, and that the very-long chain molecules could determine the quality of human development. A functional classification of FA today must be based not only on the rate of unsaturation, but also (and most importantly) on the chain length.