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ABSTRACT: The aim of this study was to assess relationships between the fatty acid contents of plasma and erythrocyte phospholipids and those in liver, heart, brain, kidney and quadriceps muscle in rats. To obtain a wide range of tissue omega-3 (n-3) long chain polyunsaturated fatty acids (LCPUFA) we subjected weanling rats to dietary treatment with the n-3 LCPUFA precursor, alpha linolenic acid (ALA, 18:3 n-3) for 3 weeks. With the exception of the brain, we found strong and consistent correlations between the total n-3 LCPUFA fatty acid content of both plasma and erythrocyte phospholipids with fatty acid levels in all tissues. The relationships between eicosapentaenoic acid (EPA, 20:5 n-3) and docosapentaenoic acid (DPA, 22:5 n-3) content in both blood fractions with levels in liver, kidney, heart and quadriceps muscle phospholipids were stronger than those for docosahexaenoic acid (DHA, 22:6 n-3). The strong correlations between the EPA+DHA (the Omega-3 Index), total n-3 LCPUFA and total n-3 PUFA contents in both plasma and erythrocyte phospholipids and tissues investigated in this study suggest that, under a wide range of n-3 LCPUFA values, plasma and erythrocyte n-3 fatty acid content reflect not only dietary PUFA intakes but also accumulation of endogenously synthesised n-3 LCPUFA, and thus can be used as a reliable surrogate for assessing n-3 status in key peripheral tissues.
Prostaglandins Leukotrienes and Essential Fatty Acids 04/2012; · 3.37 Impact Factor
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ABSTRACT: The conversion of the plant-derived omega-3 (n-3) α-linolenic acid (ALA, 18:3n-3) to the long-chain eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) can be increased by ALA sufficient diets compared to ALA deficient diets. Diets containing ALA above an optimal level result in no further increase in DHA levels in animals and humans. The present study evaluates means of maximizing plasma DHA accumulation by systematically varying both linoleic acid (LA, 18:2n-6) and ALA dietary level. Weanling rats were fed one of 54 diets for three weeks. The diets varied in the percentage of energy (en%) of LA (0.07-17.1 en%) and ALA (0.02-12.1 en%) by manipulating both the fat content and the balance of vegetable oils. The peak of plasma phospholipid DHA (>8% total fatty acids) was attained as a result of feeding a narrow dietary range of 1-3 en% ALA and 1-2 en% LA but was suppressed to basal levels (∼2% total fatty acids) at dietary intakes of total polyunsaturated fatty acids (PUFA) above 3 en%. We conclude it is possible to enhance the DHA status of rats fed diets containing ALA as the only source of n-3 fatty acids but only when the level of dietary PUFA is low (<3 en%).
Prostaglandins Leukotrienes and Essential Fatty Acids 04/2012; · 3.37 Impact Factor
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ABSTRACT: The aim of this study was to assess relationships between the fatty acid contents of plasma and erythrocyte phospholipids and those in liver, heart, brain, kidney and quadriceps muscle in rats. To obtain a wide range of tissue omega-3 (n-3) long chain polyunsaturated fatty acids (LCPUFA) we subjected weanling rats to dietary treatment with the n-3 LCPUFA precursor, alpha linolenic acid (ALA, 18:3 n-3) for 3 weeks. With the exception of the brain, we found strong and consistent correlations between the total n-3 LCPUFA fatty acid content of both plasma and erythrocyte phospholipids with fatty acid levels in all tissues. The relationships between eicosapentaenoic acid (EPA, 20:5 n-3) and docosapentaenoic acid (DPA, 22:5 n-3) content in both blood fractions with levels in liver, kidney, heart and quadriceps muscle phospholipids were stronger than those for docosahexaenoic acid (DHA, 22:6 n-3). The strong correlations between the EPA+DHA (the Omega-3 Index), total n-3 LCPUFA and total n-3 PUFA contents in both plasma and erythrocyte phospholipids and tissues investigated in this study suggest that, under a wide range of n-3 LCPUFA values, plasma and erythrocyte n-3 fatty acid content reflect not only dietary PUFA intakes but also accumulation of endogenously synthesised n-3 LCPUFA, and thus can be used as a reliable surrogate for assessing n-3 status in key peripheral tissues.
Prostaglandins Leukotrienes and Essential Fatty Acids 01/2012; · 3.37 Impact Factor
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ABSTRACT: The conversion of the plant-derived omega-3 (n-3) α-linolenic acid (ALA, 18:3n-3) to the long-chain eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) can be increased by ALA sufficient diets compared to ALA deficient diets. Diets containing ALA above an optimal level result in no further increase in DHA levels in animals and humans. The present study evaluates means of maximizing plasma DHA accumulation by systematically varying both linoleic acid (LA, 18:2n-6) and ALA dietary level. Weanling rats were fed one of 54 diets for three weeks. The diets varied in the percentage of energy (en%) of LA (0.07–17.1 en%) and ALA (0.02–12.1 en%) by manipulating both the fat content and the balance of vegetable oils. The peak of plasma phospholipid DHA (>8% total fatty acids) was attained as a result of feeding a narrow dietary range of 1–3 en% ALA and 1–2 en% LA but was suppressed to basal levels (∼2% total fatty acids) at dietary intakes of total polyunsaturated fatty acids (PUFA) above 3 en%. We conclude it is possible to enhance the DHA status of rats fed diets containing ALA as the only source of n-3 fatty acids but only when the level of dietary PUFA is low (<3 en%).
Prostaglandins, Leukotrienes and Essential Fatty Acids. 01/2012;
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ABSTRACT: The conversion of the plant-derived omega-3 (n-3) α-linolenic acid (ALA, 18:3n-3) to the long-chain eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) can be increased by ALA sufficient diets compared to ALA deficient diets. Diets containing ALA above an optimal level result in no further increase in DHA levels in animals and humans. The present study evaluates means of maximizing plasma DHA accumulation by systematically varying both linoleic acid (LA, 18:2n-6) and ALA dietary level. Weanling rats were fed one of 54 diets for three weeks. The diets varied in the percentage of energy (en%) of LA (0.07–17.1 en%) and ALA (0.02–12.1 en%) by manipulating both the fat content and the balance of vegetable oils. The peak of plasma phospholipid DHA (>8% total fatty acids) was attained as a result of feeding a narrow dietary range of 1–3 en% ALA and 1–2 en% LA but was suppressed to basal levels (∼2% total fatty acids) at dietary intakes of total polyunsaturated fatty acids (PUFA) above 3 en%. We conclude it is possible to enhance the DHA status of rats fed diets containing ALA as the only source of n-3 fatty acids but only when the level of dietary PUFA is low (<3 en%).
Prostaglandins Leukotrienes and Essential Fatty Acids 01/2012; · 3.37 Impact Factor
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ABSTRACT: Dietary n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) reduce adipogenesis and lipogenesis in adult rodents, but it is not clear whether an increased n-3 LCPUFA supply during the perinatal period influences body fat mass in the offspring. This systematic review aimed to evaluate the existing evidence from animal studies, which have addressed this question. Medline was searched for relevant articles. Studies were included if they involved maternal n-3 PUFA or LCPUFA supplementation and measured fat mass in the offspring. The design and quality of each study was assessed. Only four animal studies met our inclusion criteria. Three studies reported a lower fat mass in offspring of n-3 LCPUFA supplemented dams, however only one of these studies confined the intervention to the perinatal period. The dose of n-3 PUFA, the nature of the control treatment, the approaches used and outcomes assessed differed between studies. This review highlights the paucity of robust animal data as to the effect of increased n-3 LCPUFA exposure during the perinatal period alone, on body fat mass in the offspring and calls for further studies.
Prostaglandins Leukotrienes and Essential Fatty Acids 05/2011; 85(2):83-8. · 3.37 Impact Factor
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ABSTRACT: The conversion of linoleic acid (LA) and alpha-linolenic acid (ALA) to long chain polyunsaturated fatty acids (LCPUFA) is known to involve desaturation and elongation steps. Although there is evidence that genes for these steps can be regulated by extremes of dietary PUFA, the degree to which there is meaningful regulation of LCPUFA levels in tissues by diet as a result of changes in expression of desaturase and elongase genes is unclear. In this study, we tested the effect of increasing ALA levels in diets of rats from 0.2% to 2.9% energy (en) against a constant LA level (1%en) on plasma and liver phospholipid LCPUFA content together with the expression of hepatic genes involved in PUFA metabolism, the desaturases FADS1 and FADS2, the elongases ELOV2 and ELOV5, and the transcription factors sterol regulatory element-binding protein-1c (SREBP-1c) and peroxisome proliferator-activated receptor alpha (PPARalpha). The levels of plasma and liver eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA) increased in proportion to dietary ALA whereas docosahexaenoic acid (DHA) increased only up to 1%en ALA. A low PUFA (0.4%en) reference diet stimulated the expression of delta 6 desaturase (FADS2) and elongase 2 (ELOVL2) when compared to higher PUFA diets. There was, however, no difference in the expression of any of the genes in rats, which were fed diets containing between 0.2%en and 2.9%en ALA and mRNA expression was unrelated to tissue/plasma LCPUFA content. These data suggest that the endogenous synthesis of n-3 LCPUFA from the precursor ALA is regulated independently of changes in the expression of the synthetic enzymes or regulatory transcription factor, and provides evidence that n-3 LCPUFA synthesis is regulated more by substrate competition for existing enzymes than by an increase in their mRNA expression.
Prostaglandins Leukotrienes and Essential Fatty Acids 08/2010; 83(2):61-8. · 3.37 Impact Factor
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ABSTRACT: Docosahexaenoic acid (DHA) and arachidonic acid (AA) are important nutrients in the preterm diet and fixed ratios have been proposed for formula. We evaluated the intra- and inter-individual variation in milk fatty acids from mothers of preterm infants involved in a randomised trial of tuna oil or placebo supplementation. Milk samples were collected every 2 weeks while infants were hospitalised and fatty acids analysed by capillary gas chromatography. DHA was higher in milk of supplemented mothers than control (% total fatty acids, mean+/-SD, treatment 0.9+/-0.4, control 0.3+/-0.1, p<0.0005) and ranged between 0.3-2.5% and 0.1-1.1%, respectively. AA did not differ between groups and ranged between 0.2-0.9% and 0.3-0.9%, respectively. Control mothers milk had wider AA:DHA ratio than treatment mothers (0.4-3.2 versus 0.2-2.1). Due to the wide variation in milk AA and DHA, statements recommending infant formula based on a fixed AA:DHA ratio should be re-examined.
Prostaglandins Leukotrienes and Essential Fatty Acids 04/2010; 83(1):9-13. · 3.37 Impact Factor
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ABSTRACT: Formula supplemented with docosahexaenoic acid (DHA) improves retinal function of preterm infants but the optimal dose is unknown. In a randomized controlled trial we examined the effect of increasing the DHA concentration of human milk and formula on circulating fatty acids of preterm infants. Infants born <33 weeks gestation were fed high-DHA milk (1% total fat as DHA) or standard-DHA milk (0.2-0.3% DHA) until reaching their estimated due date (EDD). Milk arachidonic acid (AA) concentration was approximately 0.5% for both groups. At EDD, erythrocyte membrane phospholipid DHA was elevated in the high-DHA group compared with standard-DHA (mean+/-SD, high-DHA 6.8+/-1.2, standard-DHA 5.2+/-0.7, p<0.0005) but AA was lower (high-DHA 14.9+/-1.3, standard-DHA 16.0+/-1.2, p<0.0005). Feeding preterm infants human milk and formula with 1% DHA raises but does not saturate erythrocyte phospholipids with DHA. Milk exceeding 1% DHA may be required to increase DHA status to levels seen in term infants.
Prostaglandins Leukotrienes and Essential Fatty Acids 10/2008; 79(3-5):141-6. · 3.37 Impact Factor
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ABSTRACT: To compare the efficacy and side effects of low-dose vs high-dose iron supplements to correct anaemia in pregnancy.
One hundred and eighty women with anaemia (haemoglobin <110 g l(-1)) in mid-pregnancy. The women were randomly allocated to 20; 40 or 80 mg of iron daily for 8 weeks from mid-pregnancy.
One hundred and seventy-nine (99%) women completed the trial. At the end of treatment, there was a clear dose-response of increasing mean haemoglobin concentration with iron dose (111+/-13 g l(-1) at 20 mg per day, 114+/-11 g l(-1) at 40 mg per day and 119+/-12 g l(-1) at 80 mg per day, P=0.006). However, the incidence of anaemia did not differ statistically between groups. Compared with women in the 80 mg iron group, the odds ratio of anaemia was 1.9 (95% CI: 0.8, 4.3, P=0.130) and 1.1 (95% CI: 0.5, 2.6, P=0.827), respectively, for women in the 20 mg iron group and the 40 mg iron group. The incidence of gastrointestinal side effects was significantly lower for women in the 20 mg iron group compared with women in the 80 mg iron group; the odds ratio was 0.4 (95% CI: 0.2, 0.8, P=0.014) for nausea, 0.3 (95% CI: 0.2, 0.7, P=0.005) for stomach pain and 0.4 (95% CI: 0.2, 0.9, P=0.023) for vomiting.
Low-dose iron supplements may be effective at treating anaemia in pregnancy with less gastrointestinal side effects compared with high-dose supplements.
European journal of clinical nutrition 10/2007; 63(2):183-90. · 3.07 Impact Factor
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ABSTRACT: To examine the effect of nucleotide (NT)-supplemented cow's milk-based formula on growth and biochemical indices of immune function in healthy infants.
Randomized controlled trial (RCT) of formula-fed term infants allocated to control formula with an innate level of NT at 10 mg/l (n = 102), or formula fortified with NT at 33.5 mg/l (n = 98). A parallel group of 125 breastfed infants followed the same protocol as a reference.
Growth was assessed at enrolment, 7 weeks, 4 months and 7 months of age. Natural killer cell activity, cytokine production and lymphocyte subpopulations were assessed at 7 weeks of age. Antibody responses to diphtheria toxoid, tetanus toxoid and Haemophilus influenzae type b (Hib) immunizations were measured at 7 months of age.
NT supplementation did not influence the growth of formula fed infants or any markers of immunity measured at 7 weeks of age. Antibody responses to tetanus toxoid were higher in the NT-supplemented group (n = 68) compared with the control group (n = 70) at 7 months of age (median (5th, 95% percentile): 1.57(0.42, 3.43) vs 1.01(0.41, 4.66) IU/ml, P < 0.03). A difference between treatments was seen in response to diphtheria toxoid but this effect disappeared when adjusted for hepatitis B immunization at birth. There was no effect of treatment on antibody responses to Hib immunization.
Supplementation of formulas with NT at 33.5 mg/l resulted in a modest improvement in antibody response consistent with RCTs that used higher levels of NT supplementation. Whether this translates to clinical benefits in well-nourished infants requires further study.
Supported by a grant from Wyeth Nutrition. Dr Makrides was supported by an RD Wright Fellowship from the National Health and Medical Research Council of Australia and Dr Gibson was partially supported by the MS McLeod Research Trust and a Senior Research Fellowship from the National Health and Medical Research Council of Australia.
European Journal of Clinical Nutrition 03/2006; 60(2):254-64. · 2.46 Impact Factor
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ABSTRACT: Background - Docosahexaenoic acid (DHA; 22:6n-3) is the main structural lipid in the human brain and can be derived endogenously from alpha-linolenic acid (ALA; 18:3n-3). Several studies have attempted to improve blood DHA concentrations of formula-fed infants by increasing the amount of ALA in formula while measuring changes to infant growth and development. Objective - To evaluate the effect of supplementing diets of term and preterm infants with ALA on growth and development. Design - A systematic review and meta-analysis of randomised controlled trials (RCTs) involving term and preterm infants where the ALA composition of the diet was changed. Outcomes - Five term and three preterm RCTs, and three term and three preterm RCTs were included in the systematic review and meta-analysis, respectively. Infants fed ALA supplemented formula had significantly higher blood phospholipid DHA concentrations than control. Combined data suggested that ALA supplemented formulas influence the growth of term but not preterm infants. Finally, there was no effect on developmental indices of term infants but there was a transient improvement in retinal function of preterm infants' supplemented with ALA compared with control (mean difference: -0.37 scot td-sec, 95% CI: -0.66, -0.08; 36 weeks post menstrual age). Conclusions - Further studies are needed to provide convincing evidence regarding the effects of ALA supplementation on growth and development of infants.
Asia Pacific Journal of Clinical Nutrition 02/2003; 12 Suppl:S45. · 1.13 Impact Factor
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ABSTRACT: Background - The importance of feeding infants breast milk is demonstrated in decreased rates of infection and improved development. We have little understanding of the pattern or rate of breastfeeding among infants who were born premature. Objective - To determine the pattern of feeding breast milk to infants born < 33 weeks gestation. Design - One hundred infants (from 87 mothers) were enrolled at the Women's and Children's Hospital within five days of commencing enteral feeds, 95 were followed to four months corrected age (CA). The duration and proportion of breastfeeding was categorised according to World Health Organisation criteria. Data were collected during hospitalisation, at infants estimated due date (EDD), and two and four months CA. Outcomes - Eighty of 100 infants received some breast milk, similar to the initiation rates of breastfeeding among term infants. At EDD (approx 10 weeks post birth), only 18/96 (19%) infants were fully breastfed, 62 (65%) received combinations feeds and 16 (17%) were formula fed. From a total of 95 infants remaining in the study, seven (7%) were fully breastfed and 16 (17%) were formula fed through to four months CA. By four months CA, the average duration of all breastfeeding was 11+/-5 weeks, (approximately one week old CA). Conclusions - The duration and extent of breastfeeding in preterm infants is less than that observed in term infants.
Asia Pacific Journal of Clinical Nutrition 01/2003; 12 Suppl:S43. · 1.13 Impact Factor
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ABSTRACT: Background - Cross cultural comparisons and ecological studies indicate an inverse association between the incidence of post partum depression and consumption of long chain omega-3 fatty acids, such as docosahexaenoic acid (DHA). However, evidence from prospective studies is lacking. Objective - To determine is there is an association between major depressive symptoms and plasma DHA in a cohort of women at 6 months post-partum. Design - A cohort of 380 women completed an Edinburgh Post-partum Depression Scale (EPDS) and had their iron, zinc and DHA status assessed. Perinatal and social characteristics were collected at the time of birth. Women were classified with symptoms of depression if they has a score of 12 or above on the EPDS. Outcomes - Logistic regression analysis indicated that a 1% increase in plasma DHA was associated with a 59% reduction in reporting of depressive symptoms (P<0.05), while an increase in the length of hospital stay (at the time of birth) by 1 day was associated with a 19% increase in depressive symptoms (P=0.07). These associations need to be interpreted with caution because plasma DHA was positively influenced by maternal education and negatively influenced by maternal smoking. Conclusions - Randomised trials with a DHA intervention are necessary to determine whether the association between DHA and depressive symptoms in the post partum period is causal.
Asia Pacific Journal of Clinical Nutrition 01/2003; 12 Suppl:S37. · 1.13 Impact Factor
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ABSTRACT: Long-chain polyunsaturated fatty acids have been associated with aspects of immune regulation including cytokine production. The purpose of this study was to investigate the effect of maternal dietary supplementation with tuna oil, rich in docosahexaenoic acid (DHA), on the concentration of transforming growth factor beta 1 (TGFbeta1) and TGFbeta2 in breast milk. In this randomized, dietary intervention trial, mothers of term infants consumed a daily supplement of 2000 mg oil containing either placebo (n = 40), 300 mg DHA (n = 40), or 600 mg DHA (n = 40). The DHA increase in milk and plasma was proportional to dietary DHA. There was no relationship between milk DHA status and TGFbeta1 and TGFbeta2 levels.
Lipids 11/2001; 36(10):1179-81. · 2.13 Impact Factor
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ABSTRACT: Visual-evoked potential (VEP) acuity has been used to assess the effects of dietary fats on the integrity of the visual pathway of infants. We investigated prognostic determinants of VEP acuity at 16 wk of age. The results of two randomized dietary intervention trials designed to assess the effect of dietary fatty acids on the visual development of term infants were combined. At entry to both trials (approximately day 5 of life), a blood sample to assess polyunsaturated fatty acid (PUFA) status was collected along with sociodemographic and perinatal characteristics. At 16 +/- 0.9 wk of age, infants underwent VEP testing to measure acuity. There was no effect of dietary treatment on these outcomes within or between trials. Multiple linear regression models were constructed to investigate the effect of perinatal and nutritional variables at study entry on VEP acuity of 185 infants. Higher birth weight was associated with an ability to resolve smaller checkerboard patterns [r2 = 0.05; 95% confidence interval (Cl), -0.10, -0.04 log units]. Male gender (r2 = 0.03; 95% Cl, 0.01, 0.07 log units), day 5 plasma 22:5n-6 (r2 = 0.04; 95% Cl, 0.02, 0.20 log units), day 5 red cell membrane 20:3n-9 (r2 = 0.03; 95% Cl, 0.03, 0.13 log units), and the number of smokers in the household (r2 = 0.02; 95% Cl, 0.00, 0.04 log units) were all associated with poorer VEP acuity scores. It is possible that a combination of perinatal factors could accumulate to either mask or enhance effects of diet on VEP acuity, given the relatively modest effects of long-chain PUFA on visual outcome.
Lipids 10/2001; 36(9):897-900. · 2.13 Impact Factor
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ABSTRACT: The role of polyunsaturated fatty acids (PUFA) in infant nutrition has now been well studied through many randomized controlled trials (RCT) that provide us with high-quality evidence, particularly in relation to efficacy. As a result of a systematic search of the literature for RCT of supplementation of formulas of term and preterm infants with long-chain polyunsaturated fatty acids (LC-PUFA), we have identified 21 studies that have physiological responses or growth as outcomes. There have been 11 RCT involving preterm infants, and many of these claim a beneficial effect on visual, neural, or developmental outcomes. There are some reports of negative effects on growth in relation to the addition of n-3 LC-PUFA to preterm formulas but not when AA is added with n-3 LC-PUFA. Small studies have shown no differences in prostanoid formation or peroxidative stress between n-3 LC-PUFA-supplemented and unsupplemented infants. There have been 10 RCT involving term infants; whereas some studies report an effect on visual/neural/developmental outcomes, an equal number report no effect. There have been no reports of negative effects of n-3 LC-PUFA on growth in term infants. In summary, there appear to be few safety concerns relating to the use of LC-PUFA in infant nutrition. The potential medium- and long-term effects of including these compounds in the early diet of infants remain to be assessed.
Lipids 10/2001; 36(9):873-83. · 2.13 Impact Factor
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PEDIATRICS 09/2001; 108(2):465. · 4.47 Impact Factor
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ABSTRACT: The need for long-chain polyunsaturated fatty acids (LC-PUFA), such as docosahexaenoic acid (DHA, C22:6n3) and arachidonic acid (AA, C20:4n6), in the diet of infants in order to achieve full developmental potential is a matter of intense investigation by several research groups worldwide. It has been widely reported that breast-fed infants perform better on tests that assess neurodevelopmental outcomes than do formula-fed infants. Although human milk contains LC-PUFA that are absent from formula, it is necessary to demonstrate that any beneficial effects of human milk on infant development are purely attributed to the presence of LC-PUFA in human milk and their absence from formula to establish causality. The hypothesis that dietary DHA is associated with developmental outcome needs to be plausible; the effect must be consistent, specific, and independent of confounding factors. The hypothesis is certainly plausible. DHA is avidly incorporated and retained in brain cerebral phospholipids, and a most consistent finding has been the lower level of cerebral DHA in the brains of formula-fed infants (receiving no DHA) relative to those fed human milk (receiving DHA). The formula-fed infants in these studies were generally fed formulas with adequate alpha-linolenic acid levels, and this may indicate a nutritional requirement for preformed DHA. Several studies have compared the effects of breast- and formula-feeding on functional outcomes in preterm and term infants. While many of the outcomes have involved visual testing, others have attempted more global assessments. The results have shown differences in favor of breast-feeding but have been colored by the strong socioeconomic differences between mothers who choose to breast feed and those who choose formula-feeding. Randomized clinical trials involving preterm infants have shown a clear requirement for DHA for full visual and neural development. These results are consistent with primate studies. However, intervention studies with term infants that have attempted to improve the DHA supply of infant formula and hence infant development have not yielded consistent results. Some randomized studies have demonstrated improved visual and developmental indices in supplemented over unsupplemented infants, others have failed to demonstrate an effect. This disparity could be due to methodological and environmental differences. It is also notable that supplemental regimens have not specifically added DHA and have included other LC-PUFA, raising the question as to the specificity of the effect. However, only tissue DHA levels have consistently correlated with outcomes.
Advances in experimental medicine and biology 02/2001; 501:375-83. · 1.09 Impact Factor
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ABSTRACT: Factors such as cytokines and lymphocytes present in human milk can influence the developing immune system. This suggests an immunoregulatory role for human milk that is absent in infants consuming formula. There are very few data available from well-defined groups of breast-fed and formula-fed infants with regard to their immune status as reflected by lymphocyte immunophenotypic values. The aim of this study was to investigate the potential difference in lymphocyte subsets between breast-fed and formula-fed infants at 6 months of age. Blood samples were taken by venipuncture. Lymphocytes were analyzed by 2-color direct immunofluorescence with Becton Dickinson Immunocytometry Systems SimulSET reagents (BD, Franklin Lakes NJ). There were 73 breast-fed infants and 55 formula-fed infants at 6 months of age. The frequency of natural killer (NK) cells (CD3-/CD16+ + CD56+) was greater in breast-fed infants (9.2%) than in formula-fed infants (6.6%, P < 0.001), while the CD4 to CD8 ratio was 2.8 in breast-fed infants compared with 3.4 in formula-fed infants (P < 0.001). Conclusion: Breast-fed infants (<250mL formula/bovine milk per week) had a greater proportion of NK cells and a lower CD4 to CD8 ratio than formula-fed infants at 6 months of age.
Advances in experimental medicine and biology 01/2001; 501:497-504. · 1.09 Impact Factor
