The profile of fatty acids in frontal cortex of rats depends on the type of fat used in the diet and correlates with neuropeptidase activities.

The kind of fat in the diet modifies the profile of fatty acids in brain and also affects aminopeptidase activities in tissues. Although modifications in brain fatty acids, neurotransmitters, or enzymes due to dietary fat composition have been reported, no direct relationship has yet been described between specific brain fatty acid changes and neuropeptide metabolism following the fat composition of the diet. We investigated the lipid profile and some neuropeptidase activities in the frontal cortex of adult male rats after a period in which diets were supplemented with fatty acids differing in their degrees of saturation such as fish oil (rich in polyunsaturated fatty acids, PUFAs), olive oil (rich in monounsaturated fatty acids, MUFAs), and coconut oil (rich in saturated fatty acids, SAFAs). It is observed that the diet composition affects fatty acid distribution in the brain. Although there is no change of global aminopeptidase/neuropeptidase, their activities in the brain correlate positively or negatively with the dietary fat composition. It is hypothesized that fatty acid in the diet modifies membrane fluidity, peptidases tertiary structure, and therefore, the availability and function of neuropeptides. The present results support the notion that cognitive functions may be modulated depending on the type of fat used in the diet.

[The influence of human milk and various artificial formulae commercially available in Spain on the fatty acid status of infants in the first two months of life]. / Perfil de ácidos grasos a los dos meses de vida en niños alimentados con lactancia materna frente a varias fórmulas artificiales disponibles comercialmente en España.

OBJECTIVE: To evaluate changes in the fatty acid composition of red blood cell phospholipids in breast-fed infants compared with those in infants fed with different formulas (conventional, omega -6-enriched formula, omega -6- and omega -3-enriched formula and nucleotide-enriched formula). METHODS: Thirty-seven healthy term infants were randomly assigned to one of five different feeding groups. Weight, length, head circumference, and arm circumference were assessed at 7 and 60 days of age. The fatty acid composition of the infants' red blood cell phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were analyzed at these ages. RESULTS: The anthropometric variables studied showed no changes among the different groups. At 60 days old, arachidonic acid concentration (20:4 omega -6) was lower in non-omega -6 enriched formula-fed groups compared with that in the breast-milk fed group (4.03, 3.68 and 5.15 vs 7.20 g/100 g of fatty acids). Docosahexaenoic acid concentration (22:6omega -3) in both PC and PE clearly decreased in the non-omega -3 formula-fed groups compared with that in the breast-milk fed group (PC: 0.72 vs 2.82 g/100 g of fatty acids and PE: 5.15 vs 7.73 g/100 g of fatty acids). CONCLUSIONS: This study demonstrates differences in the fatty acid composition of red blood cell phospholipids between breast-milk fed infants and those fed with any of the artificial formulas available on the Spanish market. These data provide evidence of the influence of diet on certain essential fatty acids in the body.

Effects of dietary supplementation with fish oil, lard, or coconut oil on oxytocinase activity in the testis of mice.

Oxytocin (OT), locally synthesized in the testis, is involved in androgen biosynthesis. The use of polyunsaturated fatty acids (e.g., fish oil) in the diet may improve the fertilizing ability in mammals. Cystinyl aminopeptidase (oxytocinase) activity plays a major role regulating the functional status of OT. Sex steroids and the type of the fatty acid used in the diet modify aminopeptidase activities in serum. In the present study, the authors compared the effect of a fish oil supplemented diet with two other diets supplemented with saturated oils (lard and coconut) on oxytocinase activity in the testis of mice. The enzymatic activity was determined fluorometrically using cystinyl-beta-naphthylamide as substrate. The results demonstrated higher levels of oxytocinase activity in mice fed the diet supplemented with fish oil than in those that were fed diets containing lard or coconut oils. The testicular functions in which OT is involved may be attenuated by the use of fish oil in the diet.

Polyunsaturated fatty acid deficiency during dietary treatment of very long-chain acyl-CoA dehydrogenase deficiency. Rescue with soybean oil.

Nutritional management of very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is based on the avoidance of fasting and substitution of medium-chain triglycerides for long- and very long-chain triglycerides. We report two cases of this disease, which developed omega-6 essential fatty acid deficiency after three and five months from the beginning of nutritional therapy (SHS product: Monogen). This alteration could be especially dangerous in these patients owing to their possible susceptibility to the development of pigmentary retinopathy. The incorporation of linoleic acid as 3-4% of total caloric intake supported as soybean oil ameliorates this deficiency. We wish to remark on this early complication in the nutritional management of VLCAD deficiency and the possibility of rescue by the incorporation of soybean oil into the diet.

tert-Butyl hydroperoxide-induced lipid signaling in hepatocytes: involvement of glutathione and free radicals.

tert-Butyl hydroperoxide (TBHP) mobilizes arachidonic acid (AA) from membrane phospholipids in rat hepatocytes under cytotoxic conditions, thus leading to an increase in intracellular AA, which precedes cell death. In the present work, the involvement of lipid peroxidation, thiol status, and reactive oxygen species (ROS) in the intracellular AA accumulation induced by 0.5 mM TBHP was studied in rat hepatocytes. Cells treated with TBHP maintained viability and energy status at 10 min. However, TBHP depleted GSH, as well as inducing lipid peroxidation and ROS formation, detected by dichlorofluorescein (DCF) fluorescence. TBHP also significantly increased (32.5%) the intracellular [14C]-AA from [14C]-AA-labelled hepatocytes. The phospholipase A(2) (PLA(2)) inhibitor, mepacrine, completely inhibited the [14C]-AA response. The addition of antioxidants to the cell suspensions affected the TBHP-induced lipid response differently. The [14C]-AA accumulation correlated directly with ROS and negatively with endogenous GSH. No correlation between [14C]-AA and lipid peroxidation was found. Promethazine prevented lipid peroxidation and did not affect the [14C]-AA increase. We conclude that TBHP stimulates the release of [14C]-AA from membrane phospholipids through a PLA(2)-mediated mechanism. Endogenous GSH and ROS play a major role in this effect, while lipid peroxidation-related events are unlikely to be involved. Results suggest that specific ROS generated in iron-dependent reactions, different from lipid peroxyl radicals, are involved in PLA(2) activation, this process being important in TBHP-induced hepatocyte injury.

17beta-estradiol affects in vivo the low density lipoprotein composition, particle size, and oxidizability.

The aim of this study was to explore the possible modifications induced by 17beta-estradiol (E(2)) in vivo on low-density lipoprotein (LDL) lipid composition, particle size, and oxidizability. For this purpose, women were recruited from an in vitro fertilization program, ranging their plasma E(2) levels from less than 12 pg/ml to more than 2000 pg/ml at the end of the treatment. The LDL lipid constituents were analyzed by thin layer chromatography and image analysis, and the LDL diameter was calculated from the lipid data. The results showed that high plasma E(2) levels were associated with smaller LDL particles, with lower amounts of free and esterified cholesterol and an increased relative content of alpha-tocopherol. The hormonal treatment produced a remodelation of the LDL acyl composition, rendering a lipoprotein enriched in saturated fatty acids, with a poorer polyunsaturated fatty acid content. These alterations in the physicochemical properties of LDL paralleled changes in the susceptibility of LDL to in vitro oxidation induced by both Cu(2+) and the peroxyl radical generator, 2,2'-azobis (2-amidinopropane), these changes being mainly reflected in a reduced maximum oxidation rate. The in vivo changes in the physicochemical properties of LDL induced by E(2) could explain some of the antiatherogenic actions of estrogens.

[Intellectual development in the second year of life in healthy breast-fed children compared with formula-fed children]. / Desarrollo intelectual en el segundo año de vida en niños sanos lactados de forma natural frente a los lactados artificialmente.

BACKGROUND: The role of breast milk with regard to W3 long-chain polyunsaturated fatty acids and infant intellectual development remains controversial. PATIENTS AND METHODS: Thirty-nine children born at term and from homogeneous sociocultural status were enrolled in a blind-prospective trial. Children were divided in two non-randomized groups: a breast-fed group and a standard formula-fed group. Red blood cell phospholipid fatty acids were analyzed at 7 and 60 days of life. Cognitive development was evaluated at the end of the second year of life through Bailey s test. RESULTS: Concentrations of phosphatidylethanolamine and phosphatidylcholine docosahexaenoic acid were significantly lower in the formula-fed group. No statistically significant differences between groups were found in cognitive function. Brain development index was significantly correlated with infant head circumference and educational status of the mother. CONCLUSIONS: Maternal nutrition provides higher red blood cell docosahexaenoic acid, but is not related to a higher developmental quotient at the age of 2 years. However, infant head circumference and maternal educational status were correlated with developmental cognition.

Identification of a cytogenetic deletion and of four novel mutations (Q69X, I172F, G188V, G197R) affecting the gene for ornithine transcarbamylase (OTC) in Spanish patients with OTC deficiency.

A deletion of at least 11.5 cM in the paternal X chromosome mapping between microsatellites DXS989 and DXS1003 and encompassing the genes for ornithine transcarbamylase (OTC), retinitis pigmentosa GTPase regulator (RPGR) and dystrophin, was associated with the loss of band Xp21 in a female patient with OTC deficiency. Another four female patients were heterozygous for point mutations in the OTC gene: the nonsense mutation Q69X or the missense mutations I172F, G188V and G197R. In the OTC amino acid sequence, I172 and G197 are proximate to residues involved in catalysis, and G188 is within a loop joining helix 5 and strand 6 in the core of the ornithine-bindingdomain. Therefore, the mutations of these residues may cause structural changes affecting catalysis and/or the architecture of the ornithine domain. The mutation appeared "de novo" in the patients or, in one case, in the mother of the patient, in agreement with the predominance of "de novo" mutations in female patients of OTC deficiency. There was full agreement between the results of mutational analysis and of allopurinol testing in the patients and their female relatives, supporting the value of the allopurinol test in the detection of carriers of OTC deficiency. This deficiency is a genetically heterogeneous X-linked condition.

[PSAD and PSA-AD in the early diagnosis of cancer of the prostate]. / Aportación del PSAD y PSA-AD en el diagnóstico precoz del cáncer de próstata.

Presentation and analysis of results from an early diagnosis program for prostate cancer in symptomatic patients. Output of density-PSA (PASD-d), density-PSA of the transitional area (PSAD-ad) and free PSA/total PSA ratio, applied to patients with total PSA between 4 and 10 ng/ml is analyzed.