Päivi Luukkainen

Fatty Acid Composition of Serum Lipid Fractions in Relation to Gender and Quality of Dietary Fat

UNLABELLED The fatty acid compositions of serum lipid fractions are believed to reflect the quality of dietary fat, but only a few cross-sectional studies have examined these relationships in a representative free-living population. We related the composition of dietary fat obtained by 7-day food records from 84 free-living middle-aged married couples, on their habitual diets, to gas chromatographic analyses of the percentage compositions of fatty acids in three lipid fractions of fasting sera. Dietary polyunsaturated fat had Pearsons correlation coefficients of 0.63, 0.73 and 0.44 with n-6 polyunsaturated fatty acids in serum cholesteryl esters, triglycerides and phospholipids, respectively. Intake of fish showed correlations of 0.60, 0.36 and 0.52 with the percentage of eicosapentaenoate in the respective fractions. Dietary saturated fat had correlations of 0.57 and 0.54 with saturated fatty acids in serum cholesteryl esters and triglycerides, respectively. Dietary monounsaturated fat did not correlate positively with monounsaturated fatty acids in any serum lipid fraction. There were some small but significant gender differences in the serum fatty acid compositions. CONCLUSIONS of the three serum lipid fractions, triglycerides appear to be the best reflectors of dietary polyunsaturated and saturated fat, but the intake of monounsaturated fat is poorly reflected in all serum lipid fractions. Intake of fish is mirrored in all serum lipid fractions, best in cholesteryl esters and phospholipids.

Changes in the Fatty Acid Composition of Preterm and Term Human Milk from 1 Week to 6 Months of Lactation

Using capillary gas chromatography, we analyzed the fatty acid composition of human milk from 23 women who had delivered prematurely and 16 women who had delivered at term. Milk samples were obtained at 1, 2, 4, 12, and 26 weeks after delivery. The relative amounts of saturated and monounsaturated fatty acids in preterm and term milk remained stable throughout the 6 months of lactation. The proportions of linoleate (18:2n-6) and α-linolenate (18:3n-3) were similar in preterm and term milk and showed an increasing trend from transitional (8.7–9.9% and 0.9–1.1% of total fatty acids, respectively) to mature milk (9.9–11.8% and 1.2–1.5%, respectively). The proportions of the major long-chain polyun-saturated fatty acids (LCP), 20:3n-6, 20:4n-6, 22:5n-3 and 22:6n-3, were highest at 1 week and decreased thereafter in both types of milk. In term milk, the proportion of LCP continued to decrease from 1 month to 6 months, whereas in preterm milk it was fairly constant. Consequently, at 6 months of lactation, the relative content of arachidonate (20:4n-6) was 1.5 times (p < 0.05) and that of docosa-hexaenoate (22:6n-3) was two times higher (p < 0.01) in preterm than in term milk. We conclude that in long-term lactation, preterm human milk provides a significantly higher relative supply of LCP than term human milk. This higher LCP content may be of special benefit to the development of a preterm infant.

Dietary fatty acid composition during pregnancy and the risk of asthma in the offspring

To cite this article: Lumia M, Luukkainen P, Kaila M, Tapanainen H, Erkkola M, Uusitalo L, Niinistö S, Kenward MG, Ilonen J, Simell O, Knip M, Veijola R, Virtanen SM. Dietary fatty acid composition during pregnancy and the risk of asthma in the offspring. Pediatr Allergy Immunol 2011: 22: 827–835.

Birth stress increases adrenomedullin in the newborn

Adrenomedullin is a peptide that induces pulmonary vasodilation in experimental animals. Adrenomedullin was measured in blood samples from cord artery and vein from 41 term newborns. In 23 of the newborns delivered vaginally, levels of adrenomedullin in the cord artery, 71.8 ± 45.8 pg ml‐1 (mean ± SD), and vein, 75.6 ± 45.2 pg ml‐1, were significantly higher than in 18 newborns delivered by elective Caesarean section (40.7 ± 14.6pgml‐1 and 32.4 ±10.3 pgml‐1, respectively; both p < 0:01). A significant correlation existed between the concentration of adrenomedullin and pH in the cord artery (r= ‐ 0:545, p = 0:002). The fetus responds to birth stress by secreting high concentrations of adrenomedullin. As a potent vasodilator, the peptide may play a role in postnatal cardiovascular adaptation.

Validation of the Finnish ISAAC questionnaire on asthma against anti-asthmatic medication reimbursement database in 5-year-old children

Background:  Valid identification of childhood asthma at the population level for epidemiological purposes remains a challenge. We aimed at validating the Finnish version of the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire based on parental‐reported childhood asthma.

Attenuated lipid peroxidation in preterm infants during subsequent doses of intravenous lipids.

The aim of this study was to determine whether the administration of a lipid emulsion containing less polyunsaturated fatty acids but rich in monounsaturated fatty acids causes less in vivo lipid peroxidation in preterm infants. The prospective intervention study included 13 infants with birth weights and gestational ages ranging between 1,100 and 2,660 g and from 28.4 to 32.9 weeks. All were in a stable condition and randomly allocated for a 3-hour infusion (0.16 g/kg/h) of an olive oil-based and a soybean oil + medium chain fatty acid (MCT) emulsion on 2 consecutive days. Expired pentane and plasma triglycerides (TGs) were measured before, during, and after the 3-hour infusion. Basal exhaled pentane averaged 9.4 ± 7.0 pmol/kg/min (mean ± SD). During the olive oil-based emulsion, exhaled pentane increased to 95.2 ± 56.7, and during soybean oil + MCT it increased to 110 ± 93.9 pmol/kg/min (p < 0.05 both from basal, n.s. between preparations). One hour after discontinuation of the infusion, exhaled pentane returned to 21.1 ± 12.6 pmol/kg/min (p < 0.05 vs. basal). Combined data on expired pentane measurements demonstrated that on day 1 pentane peaked at 124 ± 87.0 pmol/kg/min which was significantly attenuated to 57.5 ± 24.4 pmol/kg/min after an identical dose of lipid on day 2 (p < 0.05). No difference in peak TGs was detected between the two preparations or the study days. Infusion of a constant dose of intravenous lipids on 2 subsequent days to the newborn infants is associated with a reduction in lipid peroxidation. This finding may be dependent on normal postnatal maturation or may represent an appropriate adaptive response aiming at a reduction in oxidative stress. Peroxidation of soybean oil + MCT and olive oil-based lipid emulsions was similar in the newborn infants.

Impact of solid food on plasma arachidonic and docosahexaenoic acid status of term infants at 8 months of age.

We studied healthy term infants at 6 and 8 months of age to assess the effect of fat-containing solid foods (mashed veal, chicken, and pork provided in ready-to-feed cans) on plasma long-chain polyunsaturated fatty acid (LCP) status. Twenty-one infants were breast-fed and 49 were formula-fed. The fat of the formula contained 16.2% linoleic acid and 2.3% alpha-linolenic acid but no LCPs. The solid-food intake was assessed with a 7-day dietary record. Blood samples were obtained at 6 and 8 months of age, and the fatty acid composition of plasma cholesteryl esters (CE) and phospholipids (PL) were analyzed with capillary gas liquid chromatography. The solid food-derived fat intake was higher in the formula-fed than in the breast-fed group at 6 months, and it increased significantly in both groups (from 0.15 to 0.39 g/kg/day and from 0.24 to 0.43 g/kg/day in breast-fed and formula-fed groups, respectively). The relative plasma concentrations of arachidonic acid (20:4n-6) and docosahexaenoic acid (22:6n-3) were significantly lower in the formula-fed than in the breast-fed group at both 6 and 8 months. In the formula-fed group at 8 months, the proportion of solid food-derived fat correlated positively with plasma 20:4n-6, and the mean percentage of PL-20:4n-6 were 8.0% (95% confidence interval, 7.4-8.5) and 9.0% (8.3-9.7) in its lowest and highest quartiles, respectively. In the breast-fed group, solid food-derived fat intake had no effect on plasma 20:4n-6. The two groups were similar in that solid-food fat had no effect on plasma PL- or CE-22:6n-3. In conclusion, the introduction of meat containing solid foods to formula-fed infants increases their plasma 20:4n-6, but not to levels found in breast-fed infants. Further studies are needed to establish an optimal fatty acid composition of solid foods during weaning.

Maternal dietary fat and fatty acid intake during lactation and the risk of asthma in the offspring.

Aim:  To explore the association between maternal dietary fat and fatty acid (FA) intake during lactation, and the risk of asthma in the offspring by the age of 5 years.

Maternal diet during pregnancy and lactation and cow's milk allergy in offspring.

Background/Objectives:Diet during pregnancy and lactation may have a role in the development of allergic diseases. There are few human studies on the topic, especially focusing on food allergies. We sought to study the associations between maternal diet during pregnancy and lactation and cow’s milk allergy (CMA) in offspring.Subjects/Methods:A population-based birth cohort with human leukocyte antigen-conferred susceptibility to type 1 diabetes was recruited in Finland between 1997 and 2004 (n=6288). Maternal diet during pregnancy and lactation was assessed by a validated, 181-item semi-quantitative food frequency questionnaire. Register-based information on diagnosed CMA was obtained from the Social Insurance Institution and completed with parental reports. The associations between maternal food consumption and CMA were assessed using logistic regression, comparing the highest and the lowest quarters to the middle half of consumption.Results:Consumption of milk products in the highest quarter during pregnancy was associated with a lower risk of CMA in offspring (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.37–0.86; P<0.01). When stratified by maternal allergic rhinitis and asthma, there was evidence of an inverse association between high use of milk products and CMA in offspring of non-allergic mothers (OR 0.30, 95% CI 0.13–0.69, P<0.001). Cord blood IgA correlated positively with the consumption of milk products during pregnancy, indicating exposure to CMA and activation of antigen-specific immunity in the infant during pregnancy.Conclusions:High maternal consumption of milk products during pregnancy may protect children from developing CMA, especially in offspring of non-allergic mothers.

Food consumption and risk of childhood asthma

The consumption of foods rich in n‐3 polyunsaturated fatty acids has been proposed to protect against childhood asthma. This study explores the association of food consumption (including cows milk (CM)‐free diet) in early life and the risk of atopic and non‐atopic asthma.