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1.
Artículo en Inglés | MEDLINE | ID: mdl-31186150

RESUMEN

Circulating docosahexaenoic acid (DHA) and arachidonic acid (ARA) in total red blood cells (RBC) are considered indicators of fatty acid status. In this study, healthy term infants received study formula through 120 days of age. All study formulas had 17 mg DHA/100 kcal. Investigational formulas had 1) 25 g ARA/100 kcal and no added prebiotic blend (ARA-25; n = 29) or 2) 34 mg ARA/100 kcal and a prebiotic blend (1:1 ratio; 4 g/L) of polydextrose and galactooligosaccharides (PDX/GOS; n = 20). The control formula had 34 mg ARA/100 kcal and no added prebiotic blend (Control: n = 31). Fatty acids in total RBCs and plasma phospholipids (PPLs) at 120 days and buccal epithelial PLs at 14 and 120 days of age were assessed by capillary column gas chromatography. The calculated 90% confidence interval (CI) of each investigational formula relative to the Control for total RBC ARA (ARA-25: 93-105%; PDX/GOS: 96-110%) and total RBC DHA (ARA-25: 95-113%; PDX/GOS: 94-113%) fell within the pre-specified equivalence limit (85-118%), establishing study formula equivalence with respect to ARA and DHA. At day 120, total RBC and buccal epithelia PL ARA (µg/ml) were not significantly correlated (r = 0.041; p = 0.732); correlation in total RBC and buccal epithelia PL DHA was low, albeit significant (r = 0.324; p = 0.006). Consequently, buccal epithelial may not provide a suitable substitute for RBC when assessing fatty acid status and availability. The present RBC data suggest availability of DHA for central nervous system development and function is equivalent among infants receiving formulas that had 34 or 25 mg/100 kcal ARA and 17 mg/100 kcal DHA.


Asunto(s)
Ácido Araquidónico/sangre , Estatura/fisiología , Peso Corporal/fisiología , Ácidos Docosahexaenoicos/sangre , Fórmulas Infantiles/química , Ácido Araquidónico/administración & dosificación , Estatura/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ácidos Docosahexaenoicos/administración & dosificación , Método Doble Ciego , Eritrocitos/química , Ácidos Grasos/sangre , Femenino , Glucanos/administración & dosificación , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante/efectos de los fármacos , Recién Nacido , Masculino , Mucosa Bucal/química , Oligosacáridos/administración & dosificación , Fosfolípidos/sangre , Estudios Prospectivos
2.
Artículo en Inglés | MEDLINE | ID: mdl-29413359

RESUMEN

Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are present in breast milk and play important roles in early infant development. A supply of these fatty acids in infant formula (typically following breast milk as a model with ARA > DHA) is thought to be important since endogenous synthesis is insufficient to maintain tissue levels equivalent to breast-fed infants. Intervention studies assessing the impact of DHA- and ARA-supplemented formulas have resulted in numerous positive developmental outcomes (closer to breast-fed infants) including measures of specific cognition functions, visual acuity, and immune responses. A critical analysis of outcome assessment tools reveals the essentiality of selecting appropriate, focused techniques in order to provide accurate evaluation of DHA- and ARA-supplemented formulas. Future research directions should encompass in-depth assessment of specific cognitive outcomes, immune function, and disease incidence, as well as sources of experimental variability such as the status of fatty acid desaturase polymorphisms.


Asunto(s)
Ácido Araquidónico/farmacología , Ácidos Docosahexaenoicos/farmacología , Fórmulas Infantiles/química , Fenómenos Fisiológicos Nutricionales del Lactante , Lactancia Materna , Desarrollo Infantil , Cognición/efectos de los fármacos , Cognición/fisiología , delta-5 Desaturasa de Ácido Graso , Ácido Graso Desaturasas/genética , Humanos , Inmunidad/efectos de los fármacos , Inmunidad/fisiología , Lactante , Recién Nacido , Leche Humana/química , Polimorfismo Genético , Visión Ocular/efectos de los fármacos , Visión Ocular/fisiología
3.
Artículo en Inglés | MEDLINE | ID: mdl-24863250

RESUMEN

We report the fatty acid composition of mother׳s own human milk from one of the largest US cohorts of lactating mothers of preterm infants. Milk fatty acid data were used as a proxy for intake at enrollment in infants (n=150) who received human milk with a powder human milk fortifier (HMF; Control) or liquid HMF [LHMF; provided additional 12mg docosahexaenoic acid (DHA), 20mg arachidonic acid (ARA)/100mL human milk]. Mothers provided milk samples (n=129) and reported maternal DHA consumption (n=128). Infant blood samples were drawn at study completion (Study Day 28). Human milk and infant PPL fatty acids were analyzed using capillary column gas chromatography. DHA and ARA were within ranges previously published for US term and preterm human milk. Compared to Control HMF (providing no DHA or ARA), human milk fortified with LHMF significantly increased infant PPL DHA and ARA and improved preterm infant DHA and ARA status.


Asunto(s)
Ácido Araquidónico , Ácidos Docosahexaenoicos , Alimentos Fortificados , Recien Nacido Prematuro/sangre , Leche Humana , Adulto , Ácido Araquidónico/administración & dosificación , Ácido Araquidónico/sangre , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/sangre , Método Doble Ciego , Femenino , Humanos , Recién Nacido
4.
Lipids ; 36(9): 885-95, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11724460

RESUMEN

Essential fatty acids are structural components of all tissues and are indispensable for cell membrane synthesis; the brain, retina and other neural tissues are particularly rich in long-chain polyunsaturated fatty acids (LC-PUFA). These fatty acids serve as specific precursors for eicosanoids, which regulate numerous cell and organ functions. Recent human studies support the essential nature of n-3 fatty acids in addition to the well-established role of n-6 essential fatty acids in humans, particularly in early life. The main findings are that light sensitivity of retinal rod photoreceptors is significantly reduced in newborns with n-3 fatty acid deficiency, and that docosahexaenoic acid (DHA) significantly enhances visual acuity maturation and cognitive functions. DHA is a conditionally essential nutrient for adequate neurodevelopment in humans. Comprehensive clinical studies have shown that dietary supplementation with marine oil or single-cell oil sources of LC-PUFA results in increased blood levels of DHA and arachidonic acid, as well as an associated improvement in visual function in formula-fed infants matching that of human breast-fed infants. The effect is mediated not only by the known effects on membrane biophysical properties, neurotransmitter content, and the corresponding electrophysiological correlates but also by a modulating gene expression of the developing retina and brain. Intracellular fatty acids or their metabolites regulate transcriptional activation of gene expression during adipocyte differentiation and retinal and nervous system development. Regulation of gene expression by LC-PUFA occurs at the transcriptional level and may be mediated by nuclear transcription factors activated by fatty acids. These nuclear receptors are part of the family of steroid hormone receptors. DHA also has significant effects on photoreceptor membranes and neurotransmitters involved in the signal transduction process; rhodopsin activation, rod and cone development, neuronal dendritic connectivity, and functional maturation of the central nervous system.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Ojo/crecimiento & desarrollo , Ácidos Grasos Esenciales/farmacología , Ácidos Grasos Esenciales/fisiología , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Electrofisiología , Ojo/efectos de los fármacos , Femenino , Regulación de la Expresión Génica , Humanos , Recién Nacido , Neuronas/efectos de los fármacos , Neuronas/fisiología
5.
J Lipid Res ; 42(9): 1395-401, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11518758

RESUMEN

Many patients with X-linked retinitis pigmentosa (XLRP) have lower than normal blood levels of the long-chain polyunsaturated omega3 fatty acid docosahexaenoic acid (DHA; 22:6omega3). This clinical trial was designed to test whether down-regulation of DHA biosynthesis might be responsible for these reduced DHA levels. DHA biosynthesis was assessed in five severely affected patients with XLRP and in five age-matched controls by quantifying conversion of [U-(13)C]alpha-linolenic acid (alpha-LNA) to [(13)C]DHA. Following oral administration of [U-(13)C]alpha-LNA, blood samples were collected at designated intervals for 21 days and isotopic enrichment of all omega3 fatty acids was determined by gas chromatography/mass spectroscopy. Activity of each metabolic step in the conversion of alpha-LNA to DHA was determined by comparison of the ratios of the integrated concentration of (13)C-product to (13)C-precursor in plasma total lipid fractions. The ratio of [(13)C]DHA to [(13)C]18:3omega3 (the entire pathway) and that of [(13)C]20:5omega3 to [(13)C]20:4omega3 (Delta(5)-desaturase) were significantly lower in patients versus controls (P = 0.03 and 0.05, respectively). The estimated biosynthetic rates of [(13)C]20:5omega3, [(13)C]22:5omega3, [(13)C]24:5omega3, [(13)C]24:6omega3, and [(13)C]22:6omega3 were significantly lower in XLRP patients (42%, 43%, 31%, 18%, and 32% of control values, respectively; P < 0.04), supporting down-regulation of Delta(5)-desaturase in XLRP. The disappearance of (13)C-labeled fatty acids from plasma was not greater in XLRP patients compared with controls, suggesting that XLRP was not associated with increased rates of fatty acid oxidation or other routes of catabolism.Thus, despite individual variation among both patients and controls, the data are consistent with a lower rate of Delta(5)-desaturation, suggesting that decreased biosynthesis of DHA may contribute to lower blood levels of DHA in patients with XLRP.


Asunto(s)
Ácidos Docosahexaenoicos/sangre , Ligamiento Genético , Retinitis Pigmentosa/sangre , Cromosoma X , Adulto , Pruebas Respiratorias , Dióxido de Carbono/análisis , Isótopos de Carbono , delta-5 Desaturasa de Ácido Graso , Ácido Graso Desaturasas/metabolismo , Ácidos Grasos Omega-3/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Humanos , Cinética , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Retinitis Pigmentosa/genética , Ácido alfa-Linolénico/metabolismo
6.
Am J Clin Nutr ; 71(1 Suppl): 245S-50S, 2000 01.
Artículo en Inglés | MEDLINE | ID: mdl-10617979

RESUMEN

The interest in factors that modify early infant development has led investigators to focus on n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFAs) in the past 2 decades. The presence of docosahexaenoic acid (DHA) and arachidonic acid (AA) in breast milk, compared with their absence from infant formulas available in the United States, has prompted clinical trials designed to examine whether LCPUFA enrichment of infant formula has beneficial effects on maturational events of the visual system. These trials have shown significant functional advantages of LCPUFA supplementation for preterm infants, whereas benefits for full-term infants remain controversial. The growth and safety of preterm infants was not compromised by LCPUFA enrichment, although these issues remain to be resolved in clinical trials with full-term infants.


Asunto(s)
Ácidos Grasos Esenciales/metabolismo , Fenómenos Fisiológicos Nutricionales del Lactante , Recien Nacido Prematuro , Adulto , Ácido Araquidónico/metabolismo , Encéfalo/crecimiento & desarrollo , Cognición , Ácidos Grasos Esenciales/fisiología , Femenino , Humanos , Lactante , Alimentos Infantiles , Recién Nacido , Ácido Linoleico/metabolismo , Leche Humana/química , Leche Humana/metabolismo , Necesidades Nutricionales , Retina/crecimiento & desarrollo , Agudeza Visual , Ácido alfa-Linolénico/metabolismo
7.
J Pediatr Gastroenterol Nutr ; 31(5): 540-53, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11144440

RESUMEN

BACKGROUND: In contrast to human milk, current infant formulas in the United States do not contain omega3 and omega6 long-chain polyunsaturated fatty acids. This may lead to suboptimal blood lipid fatty acid profiles and to a measurable diminution of visual function in developing term infants. The need for docosahexaenoic acid and arachidonic acid supplementation in the infant diet was evaluated in a double-blind, randomized clinical trial. METHODS: Healthy term infants were randomized to diets of (1) commercial formula, (2) docosahexaenoic acid-enriched formula (0.35% of total fatty acids), or (3) docosahexaenoic acid- (0.36%) and arachidonic acid- (0.72%) enriched formula. Eighty-seven infants completed the 17-week nutritional trial, and 58 were observed until 52 weeks of life. A reference group was exclusively breast fed for at least 17 weeks (n = 29). Outcome measures included electroretinographic responses, visual evoked potentials, and blood fatty acid analysis in infants at birth and at 6, 17, and 52 weeks of age. RESULTS: Commercial formula-fed infants had 30% to 50% lower content of docosahexaenoic acid in total red blood cell lipids during the 17-week feeding trial compared with breastfed infants. Significant differences persisted at the 1-year follow-up. Arachidonic acid content was consistently reduced in the commercial formula group by 15% to 20%. Infants fed long-chain polyunsaturated fatty acid-enriched formulas had docosahexaenoic acid and arachidonic acid blood lipid profiles resembling those of human milk-fed infants. Infants receiving this enriched formula had more mature electroretinographic responses than commercial formula-fed infants at 6 weeks of age. Human milk-fed and docosahexaenoic acid-enriched formula-fed infants had better visual acuity than commercial formula-fed infants at both 17 and 52 weeks of age. Early (17-week) fatty acid profiles in blood lipids were correlated with later (52-week) visual function development in study infants. CONCLUSIONS: Results from this clinical trial demonstrate that long-chain polyunsaturated fatty acid supplementation of formula in term infants produces blood lipid fatty acid profiles that are similar to those observed in breast-fed infants. This supplementation leads to better visual function later in life (i.e., 1 year of age) than that shown by infants fed commercial formula.


Asunto(s)
Ácido Araquidónico/farmacología , Ácidos Docosahexaenoicos/farmacología , Potenciales Evocados Visuales/efectos de los fármacos , Ácidos Grasos/sangre , Alimentos Infantiles , Agudeza Visual/efectos de los fármacos , Ácido Araquidónico/administración & dosificación , Ácido Araquidónico/sangre , Alimentación con Biberón , Lactancia Materna , Estudios de Cohortes , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/sangre , Método Doble Ciego , Electrorretinografía , Eritrocitos/química , Potenciales Evocados Visuales/fisiología , Ácidos Grasos/análisis , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-6 , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/análisis , Femenino , Sangre Fetal/química , Humanos , Lactante , Alimentos Infantiles/análisis , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Lípidos/sangre , Lípidos/química , Retina/efectos de los fármacos , Retina/fisiología , Agudeza Visual/fisiología
8.
Dev Med Child Neurol ; 42(3): 174-81, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10755457

RESUMEN

The effects of dietary docosahexaenoic acid (DHA) supply during infancy on later cognitive development of healthy term infants were evaluated in a randomized clinical trial of infant formula milk supplemented with 0.35% DHA or with 0.36% DHA and 0.72% arachidonic acid (AA), or control formula which provided no DHA or AA. Fifty-six 18-month-old children (26 male, 30 female) who were enrolled in the trial within the first 5 days of life and fed the assigned diet to 17 weeks of age were tested using the Bayley Scales of Infant Development, 2nd edition (BSID-II) (Bayley 1993) at the Retina Foundation of the Southwest, Dallas, TX. These children had also been assessed at 4 months and 12 months of age for blood fatty-acid composition, sweep visual evoked potential (VEP) acuity, and forced-choice preferential looking (FPL) acuity (Birch et al. 1998). Supplementation of infant formula with DHA+AA was associated with a mean increase of 7 points on the Mental Development Index (MDI) of the BSID-II. Both the cognitive and motor subscales of the MDI showed a significant developmental age advantage for DHA- and DHA+AA-supplemented groups over the control group. While a similar trend was found for the language subscale, it did not reach statistical significance. Neither the Psychomotor Development Index nor the Behavior Rating Scale of the BSID-II showed significant differences among diet groups, consistent with a specific advantage of DHA supplementation on mental development. Significant correlations between plasma and RBC-DHA at 4 months of age but not at 12 months of age and MDI at 18 months of age suggest that early dietary supply of DHA was a major dietary determinant of improved performance on the MDI.


Asunto(s)
Ácido Araquidónico/administración & dosificación , Desarrollo Infantil , Cognición/fisiología , Ácidos Docosahexaenoicos/administración & dosificación , Alimentos Infantiles , Análisis de Varianza , Desarrollo Infantil/fisiología , Femenino , Humanos , Lactante , Lípidos/sangre , Masculino , Destreza Motora/fisiología , Estadísticas no Paramétricas , Agudeza Visual/fisiología
9.
Lipids ; 34(4): 337-42, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10443966

RESUMEN

Cheek cells (buccal epithelia) were utilized as a noninvasive index of fatty acid status in a study of the effects of n-3 long chain polyunsaturated fatty acid supplementation on visual function in preterm infants. The fatty acid profile of cheek cell phospholipids was directly correlated with the dietary docosahexenoic acid (DHA) intake of infants receiving: (i) primarily human milk; (ii) n-3 fatty acid-deficient, corn oil-based, commercial formula (CO); (iii) alpha-linolenic acid-enriched, soy oil-based, commercial formula; or (iv) experimental formula enriched with soy and marine oils providing a DHA level equivalent to that in human milk. In a subset of infants with complete cheek cell fatty acid profiles and visual function assessments, preterm infants at both 36 wk (n = 63) and 57 wk (n = 45) postconceptional age had significantly (P < 0.0005) reduced cheek cell phospholipid DHA levels in the n-3-deficient, CO-fed group compared to the other diet groups. The DHA content in cheek cell phospholipids was highly correlated (P < 0.0005) with that of both red blood cell lipids and plasma phospholipids at the 36- and 57-wk time points. The DHA content in cheek cell lipids of infants at 36 wk was significantly correlated with electroretinographic responses (r = -0.29; P < 0.03) and visual acuity (r = -0.31; P < 0.02) as measured by visual-evoked potentials (VEP). Cheek cell DHA was highly correlated (r= -0.57; P < 0.0005) with VEP acuity at the 57-wk time point. These results suggest that the fatty acid profile of cheek cells is a valid index of essential fatty acid status, can be monitored frequently, and is associated with functional parameters in infants.


Asunto(s)
Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Grasos/análisis , Recien Nacido Prematuro , Mucosa Bucal/química , Fosfolípidos/química , Mejilla , Dieta , Humanos , Recién Nacido , Mucosa Bucal/citología , Estudios Prospectivos
10.
Pediatr Res ; 44(2): 201-9, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9702915

RESUMEN

The need for a dietary supply of docosahexaenoic acid (DHA) and arachidonic aid (AA) in term infants was evaluated in a double-masked randomized clinical trial of the effects of supplementation of term infant formula with DHA (0.35% of total fatty acids) or with DHA (0.36%) and AA (0.72%) on visual acuity development. One hundred and eight healthy term infants were enrolled in the study; 79 were exclusively formula-fed from birth (randomized group) and 29 were exclusively breast-fed (gold standard group). Infants were evaluated at four time points during the first 12 mo of life for blood fatty acid composition, growth, sweep visual evoked potential (VEP) acuity, and forced choice preferential looking acuity. Supplementation of term infant formula with DHA or with DHA and AA during the first 4 mo of life yields clear differences in total red blood cell (RBC) lipid composition. Supplementation of term infant formula with DHA or with DHA and AA also yields better sweep VEP acuity at 6, 17, and 52 wk of age but not at 26 wk of age, when acuity development reaches a plateau. The RBC lipid composition and sweep VEP acuity of supplemented infants was similar to that of human milk-fed infants, whereas the RBC lipid composition and sweep VEP acuity of unsupplemented infants was significantly different from human milk-fed infants. Differences in acuity among diet groups were too subtle to be detected by the forced choice preferential looking protocol. Infants in all diet groups had similar rates of growth and tolerated all diets well. Thus, early dietary intake of preformed DHA and AA appears necessary for optimal development of the brain and eye of the human infant.


Asunto(s)
Ácido Araquidónico/administración & dosificación , Dieta , Ácidos Docosahexaenoicos , Fenómenos Fisiológicos Nutricionales del Lactante , Agudeza Visual , Ácido Araquidónico/fisiología , Lactancia Materna , Potenciales Evocados Visuales , Ácidos Grasos Esenciales/administración & dosificación , Ácidos Grasos Esenciales/fisiología , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/fisiología , Femenino , Humanos , Lactante , Recién Nacido , Masculino
12.
J Allergy Clin Immunol ; 95(5 Pt 1): 970-8, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7751518

RESUMEN

BACKGROUND: Monoclonal antibodies were obtained against an unknown allergen from Lolium perenne grass pollen. The allergen had an apparent molecular mass of 18 kd on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Earlier immunoblotting studies had shown that carbohydrate-specific IgG antibodies recognize an antigen of similar size. OBJECTIVE: We sought to characterize the allergen biochemically and immunologically. METHODS: The amino acid sequence of the allergen was determined by automated Edman degradation, and its monosaccharide composition was determined by gas chromatographic analysis. A panel of 270 grass pollen-positive sera was assessed in a RAST with the purified allergen. Protease digestion (proteinase K) and chemical deglycosylation (trifluoromethane sulfonic acid) were used to distinguish between carbohydrate and peptide epitopes for IgE antibodies. RESULTS: The allergen was shown to be a glycoprotein with a molecular mass of 16 kd, of which 8% is carbohydrate. Its amino acid sequence shares 32% homology with soybean trypsin inhibitor (Kunitz) but lacks its active site. No homology was found with known grass pollen allergens, hence it was designated Lol p XI. A high degree of homology (44%) was found with a tree pollen allergen, Ole e I, the major allergen of olive pollen. More than 65% of grass pollen-positive sera had IgE against Lol p XI. IgE reactivity was demonstrated both with the carbohydrate moiety and the peptide backbone. CONCLUSIONS: Lol p XI is a new major grass pollen allergen carrying an IgE-binding carbohydrate determinant. Lol p XI is structurally related to the major allergen from olive pollen.


Asunto(s)
Alérgenos/inmunología , Glicoproteínas/inmunología , Lolium/inmunología , Proteínas de Plantas/inmunología , Polen/inmunología , Alérgenos/química , Secuencia de Aminoácidos , Antígenos de Plantas , Sitios de Unión , Glicoproteínas/química , Humanos , Inmunoglobulina E/inmunología , Lolium/química , Datos de Secuencia Molecular , Monosacáridos/análisis , Monosacáridos/inmunología , Proteínas de Plantas/química , Polen/química , Análisis de Secuencia , Homología de Secuencia de Aminoácido , Inhibidor de la Tripsina de Soja de Kunitz/química , Inhibidor de la Tripsina de Soja de Kunitz/inmunología
13.
Invest Ophthalmol Vis Sci ; 36(6): 1009-18, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7730010

RESUMEN

PURPOSE: Abnormalities in the distribution of long-chain polyunsaturated fatty acids (LCPUFA) have been documented in plasma of patients with X-linked retinitis pigmentosa (XLRP). In this study, fatty acid profiles of red blood cells (RBC) were used as an index for LCPUFA metabolism in patients with XLRP because RBC lipids reflect membrane-associated fatty acids. Correlations between LCPUFA content and electroretinographic (ERG) function were assessed. METHODS: Mean ages for the XLRP group (n = 18) and control group (n = 28) were 22 +/- 18 years and 24 +/- 16 years, respectively. Electroretinographic assessment included the International Society for the Clinical Electrophysiology of Vision standard protocol. Methyl esters of RBC fatty acids were analyzed by capillary column gas chromatography. RESULTS: The content of the omega 3 fatty acid, docosahexaenoic acid (DHA), was 40% lower in the group with XLRP (23.1 +/- 5.9 micrograms/ml RBC [mean +/- 1 SD]) than in normal subjects (38.6 +/- 9.4 micrograms/ml RBC, t = 6.24, P < 0.0001). Total omega 3 LCPUFA content in patients with XLRP was reduced by 30% from normal levels compared to a 10% reduction in omega 6 LCPUFA levels. Elongation reactions for omega 3, omega 6, saturated fatty acids, and monounsaturated fatty acids were markedly lower for patients with XLRP than for normal subjects. Multiple regression analysis revealed that RBC-DHA was a significant determinant for amplitude and implicit time of cone ERG responses. CONCLUSIONS: The overwhelming majority of patients with XLRP have lower levels of DHA in RBCs compared to normally sighted control subjects. An analysis of fatty acid profiles suggests a metabolic defect in fatty acid chain elongation mechanisms. The significant association between DHA content and cone ERG response parameters is consistent with an effect of lipid abnormalities on membrane environment and physiology in retinal photoreceptors.


Asunto(s)
Ácidos Docosahexaenoicos/metabolismo , Eritrocitos/metabolismo , Retinitis Pigmentosa/sangre , Retinitis Pigmentosa/genética , Cromosoma X , Adolescente , Adulto , Anciano , Niño , Preescolar , Cromatografía de Gases , Electrorretinografía , Ácidos Grasos Omega-3/metabolismo , Femenino , Ligamiento Genético/genética , Humanos , Masculino , Persona de Mediana Edad , Retina/fisiología , Retinitis Pigmentosa/fisiopatología
14.
Exp Eye Res ; 60(3): 279-89, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7789408

RESUMEN

Abnormalities in lipid metabolism have been reported in numerous patients with retinitis pigmentosa. As an initial step in evaluating these anomalies, two trials of fatty acid intervention were conducted with autosomal dominant retinitis pigmentosa (adRP) patients and controls. The first trial addressed absorption and incorporation of omega 3 long-chain fatty acids from a fish-oil concentrate into red blood cell (RBC) lipids. The utilization of omega 3 long-chain fatty acids by adRP patients was found to be equivalent to that of controls. The second trial addressed the conversion of precursor, eicosapentaenoic acid (EPA, 20:5 omega 3), to end-product, docosahexaenoic acid (DHA, 22:6 omega 3), following oral supplementation of EPA ethyl ester. Although the levels of EPA and the intermediate, docosapentaenoic acid (22:5 omega 3), were both elevated by EPA supplementation in RBCs of adRP patients with rhodopsin gene mutations and controls, DHA production was elevated only in controls. Based on these results, we suggest the presence of a metabolic defect in the final stages of DHA biosynthesis.


Asunto(s)
Eritrocitos/metabolismo , Ácidos Grasos Omega-3/sangre , Retinitis Pigmentosa/sangre , Adulto , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Electrorretinografía , Ácidos Grasos Insaturados/sangre , Femenino , Genes Dominantes , Humanos , Masculino , Persona de Mediana Edad , Mutación , Retina/fisiopatología , Retinitis Pigmentosa/genética , Rodopsina/genética
16.
J Pediatr ; 124(4): 612-20, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7908693

RESUMEN

Because formula-fed preterm infants may be at risk of omega 3 essential fatty acid deficiency, we tested experimental formulas supplemented with soy oil to provide alpha-linolenic acid or marine oil to provide preformed omega 3 long-chain polyunsaturated fatty acids at a level comparable to that of human milk. This report addresses the effect of feeding formula supplemented with soy oil or with soy and marine oils on growth, clinical tolerance, coagulation test results, changes in erythrocyte membrane fluidity, and plasma concentrations of vitamins A and E in very low birth weight infants from 30 to 57 weeks of postconceptional age. "Healthy" preterm infants were maternally selected to receive human milk or selected at random to receive commercial ready-to-feed liquid formula, which provided limited omega 3 fatty acid, or experimental formulas supplemented with soy oil or soy and marine oils. Results of this study indicate that formula enriched with soy oil or soy and marine oils containing preformed omega 3 long-chain polyunsaturated fatty acids does not induce abnormalities in growth, clotting function, erythrocyte membrane fluidity, or vitamin A or E levels in healthy very low birth weight preterm infants. Additional studies to evaluate safety in a representative preterm population are required.


Asunto(s)
Aceites de Pescado/administración & dosificación , Alimentos Fortificados , Alimentos Infantiles , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido de Bajo Peso/fisiología , Aceite de Soja/administración & dosificación , Análisis de Varianza , Femenino , Crecimiento , Humanos , Recién Nacido , Recien Nacido Prematuro/fisiología , Masculino , Ácido alfa-Linolénico/administración & dosificación
18.
Exp Eye Res ; 57(3): 359-68, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8224023

RESUMEN

Fatty acid profiles were determined in red blood cell (RBC), plasma lipids and lipid fractions from 50 patients with autosomal dominant retinitis pigmentosa (ADRP) and 20 normal-sighted controls. In plasma of affected patients, significant increases in omega 6 long-chain derivatives compared to controls resulted in elevated fatty acid unsaturation whereas, in RBCs, significant decreases in the levels of omega 6 and omega 3 long-chain polyunsaturates and a reduced unsaturation index were demonstrated (P < 0.01). The disproportionate levels of long-chain fatty acids in plasma vs. RBCs were consistent with abnormal function of acyl group transfer from plasma lipids to target tissues such as RBCs or, possibly, retina. Metabolic lipid anomalies were evaluated in two sub-groups of patients with ADRP; ten with the highest and ten with the lowest RBC lipid levels of the omega 3 fatty acid, docosahexaenoic acid (DHA). Fatty acid product/precursor relationships in the sub-groups revealed reduced chain elongation and omega 3 fatty acid desaturation associated with reduced ratios of rod-to-cone electroretinographic amplitudes. Based on these results, we suggest that the heterogenic ADRP population includes a sub-group of patients characterized by abnormal fatty acid metabolism that may effect membrane structure and visual function.


Asunto(s)
Eritrocitos/metabolismo , Ácidos Grasos/sangre , Retinitis Pigmentosa/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Electrorretinografía , Ácidos Grasos Omega-3/sangre , Humanos , Persona de Mediana Edad , Células Fotorreceptoras Retinianas Bastones/fisiopatología , Retinitis Pigmentosa/fisiopatología , Agudeza Visual
19.
Am J Clin Nutr ; 57(5 Suppl): 807S-812S, 1993 05.
Artículo en Inglés | MEDLINE | ID: mdl-8475899

RESUMEN

Deficiency of omega 3 long-chain polyunsaturated fatty acids (LCPUFAs) in vertebrates produces subtle adverse effects on visual and neural function. Preterm infants 1) are deprived of vital intrauterine fat accretion during late pregnancy, 2) must rely solely on formula for fatty acid supplies if not breastfed, and 3) may have limited postnatal desaturase activity. In a study to evaluate the necessity of dietary omega 3 LCPUFAs, preterm infants were fed human milk, corn-oil-based formula (omega 3 fatty acid deficient), soy-oil-based formula (rich in precursor fatty acids), or marine-oil-supplemented formula (containing docosahexaenoic acid). At 36 and 57 wk postconception, the LCPUFA profiles in red blood cell lipids were nearly equivalent in the human-milk and marine-oil groups whereas the corn-oil group had markedly lower values for omega 3 fatty acids. Rod photoreceptor function was significantly less mature in the corn-oil group compared with the human-milk and marine-oil-enriched groups in early postnatal development (36 wk). The corn-oil group also had impaired visual acuity at both 36 and 57 wk. The potential benefit of omega 3 LCPUFA-enriched full-term formula is discussed. The study supports a role for omega 3 LCPUFAs as required nutrients for the optimal maturation of visual and cortical function in preterm infants.


Asunto(s)
Ácidos Docosahexaenoicos/administración & dosificación , Eritrocitos/química , Ácidos Grasos Insaturados/administración & dosificación , Recién Nacido de Bajo Peso/fisiología , Retina/fisiología , Corteza Visual/fisiología , Lactancia Materna , Ácidos Docosahexaenoicos/análisis , Ácidos Grasos Insaturados/análisis , Alimentos Formulados , Humanos , Alimentos Infantiles , Recién Nacido , Células Fotorreceptoras/fisiología
20.
Lipids ; 27(11): 886-95, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1362792

RESUMEN

Pre-term infants, that are not breast-fed, are deprived of vital intrauterine fat accretion during late pregnancy and must rely on formula to obtain fatty acids essential for normal development, particularly of the visual system. Preterm infants (30 wk postconception) receiving human milk were compared to infants given one of the following formulae: Formula A was a commercial preterm formula with predominantly 18:2 omega 6 (24.2%) and low (0.5%) 18:3 omega 3; Formula B was based on soy oil and contained similar 18:2 omega 6 levels (20%) and high 18:3 omega 3 (2.7%); Formula C was also a soy oil-based formula (20% 18:2, 1.4% 18:3) but was supplemented with marine oil to provide omega 3 long-chain polyunsaturated fatty acids (LCP) at a level (docosahexaenoic acid, DHA, 0.35%) equivalent to human milk. At entry (10 days of age), the fatty acid composition of plasma and red blood cell (RBC) membrane lipids of the formula groups were identical. By 36 wk postconception, the DHA content in lipids of group A was significantly reduced compared to that in the human milk and marine oil formula groups. Omega-3 LCP results were further amplified by 57 wk with compensatory increases in 22:5 omega 6 in both plasma and RBC lipids. Provision of 2.7% alpha-linolenic acid in formula group B was sufficient to maintain 22:6 omega 3 levels equivalent to those in human milk-fed infants at 36 wk but not at 57 wk. Effects on the production of thiobarbituric acid reactive substances and fragility of RBC attributable to the marine oil supplementation were negligible. The results support the essentiality of omega 3 fatty acids for preterm infants to obtain fatty acid profiles comparable to infants receiving human milk. Formula for preterm infants should be supplemented with omega 3 fatty acids including LCP.


Asunto(s)
Eritrocitos/metabolismo , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos/sangre , Fenómenos Fisiológicos Nutricionales del Lactante , Recien Nacido Prematuro/fisiología , Necesidades Nutricionales , Dieta , Ácidos Docosahexaenoicos/administración & dosificación , Eritrocitos/fisiología , Aceites de Pescado/administración & dosificación , Humanos , Alimentos Infantiles , Recién Nacido , Ácidos Linolénicos/administración & dosificación , Peroxidación de Lípido , Leche Humana , Ácido alfa-Linolénico
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