Leslie Couëdelo

Dietary emulsifiers from milk and soybean differently impact adiposity and inflammation in association with modulation of colonic goblet cells in high‐fat fed mice

SCOPE Enhanced adiposity and metabolic inflammation are major features of obesity that could be impacted by dietary emulsifiers. We investigated in high-fat fed mice the effects of using a new polar lipid (PL) emulsifier from milk (MPL) instead of soybean lecithin (soybean PL [SPL]) on adipose tissue and intestinal mucosa function. METHODS AND RESULTS Four groups of C57BL6 mice received for 8 wks a low-fat (LF) diet or a high-fat diet devoid of PLs or an high-fat diet including MPL (high-fat-MPL) or SPL (high-fat-SPL). Compared with high-fat diet, high-fat-SPL diet increased white adipose tissue (WAT) mass (p < 0.05), with larger adipocytes (p < 0.05) and increased expression of tumor necrosis factor alpha, monochemoattractant protein-1, LPS-binding protein, and leptin (p < 0.05). This was not observed with high-fat-MPL diet despite similar dietary intakes and increased expression of fatty acid transport protein 4 and microsomal TG transfer protein, involved in lipid absorption, in upper intestine (p < 0.05). High-fat-MPL mice had a lower expression in WAT of cluster of differentiation 68, marker of macrophage infiltration, versus high-fat and high-fat-SPL mice (p < 0.05), and more goblet cells in the colon (p < 0.05). CONCLUSIONS Unlike SPL, MPL in the high-fat diet did not induce WAT hypertrophy and inflammation but increased colonic goblet cells. This supports further clinical exploration of different sources of dietary emulsifiers in the frame of obesity outbreak.

The Fraction of α-Linolenic Acid Present in the sn-2 Position of Structured Triacylglycerols Decreases in Lymph Chylomicrons and Plasma Triacylglycerols during the Course of Lipid Absorption in Rats

Little is known about the ability of α-linolenic acid (Ln) to remain in the sn-2 position of TG during the absorption process. The goal of this study was to determine the Ln distribution in the lymph (Study 1) and plasma (Study 2) TG of rats fed a single i.g. load of structured TG [300 mg/rat of either oleic acid (O)/Ln/O TG (OLnO) or Ln/O/O TG (LnOO), n = 7 rats]. In an early fraction (3-4 h) of lymph (OLnO group; 100% Ln in the sn-2 position), 46 ± 2% Ln was maintained in this position in lymph TG. There was even less (29 ± 6%) in the last fraction (7-24 h) (P < 0.05). Ln was also found (9 ± 3%) in the sn-2 position of lymph TG in the LnOO group. The Ln content in lymph phospholipids was twice as high in rats when they were fed LnOO (4.2 ± 0.1%) than OLnO (2.3 ± 0.2%) (P < 0.005). Six hours postprandially (Study 2), 21 ± 3% of the Ln incorporated into plasma TG was located in the sn-2 position in the OLnO group compared to 13 ± 2% in the LnOO group (P < 0.001). Overall, these results indicate that the amount of Ln that moved from the sn-2 position of structured TG to the sn-1(3) position of lymph TG increased during absorption. This may account for a substantial hydrolysis of the 2-monolinolenylglycerols in enterocytes, leading to the intramolecular redistribution of Ln in lymph TG and, consequently, in plasma TG.

Effects of Maternal Supplementation With Omega-3 Precursors on Human Milk Composition:

Background: Long-chain polyunsaturated fatty acids (LC-PUFAs) are important for newborn neurosensory development. Supplementation of breastfeeding mothers’ diets with omega-3 PUFAs, such as alpha-linolenic acid (ALA), may increase their concentration in human milk. Research aim: This study aimed to assess human milk composition after 15-day supplementation regimens containing either omega-3 PUFAs or olive oil, which does not provide ALA. Methods: A multicenter factorial randomized trial was conducted with four groups of breastfeeding women, with each group containing 19 to 22 women. After a 15-day ALA washout period, three groups received supplementation with omega-3 precursors for 15 days: an enriched margarine (M), a rapeseed oil (R), and a margarine and rapeseed oil (MR). The fourth was unexposed to omega-3 precursors (olive oil control diet, O). After 15 days, blind determination of human milk fatty acid (FA) composition was assessed by gas chromatography, and the FA composition was compared among groups using variance analyses. Results: Alpha-linolenic acid content, expressed as the mean (standard deviation) total human milk FA percentage, was significantly higher after diet supplementation with omega-3 PUFAs, with values of 2.2% (0.7%) (MR), 1.3% (0.5%) (R), 1.1% (0.4%) (M), and 0.8% (0.3%) (O at D30) (p < .003 for each comparison). The lowest LA–ALA ratio (5.5) was found in the MR group (p < .001). Docosahexaenoic acid and trans FA concentrations did not differ among groups. Conclusion: In lactating women, omega-3 supplementation via the combination of enriched margarine and rapeseed oil increased the ALA content of human milk and generated the most favorable LA–ALA ratio for LC-PUFA synthesis.

Soybean polar lipids differently impact adipose tissue inflammation and the endotoxin transporters LBP and sCD14 in flaxseed vs. palm oil-rich diets

Obesity and type 2 diabetes are nutritional pathologies, characterized by a subclinical inflammatory state. Endotoxins are now well recognized as an important factor implicated in the onset and maintain of this inflammatory state during fat digestion in high-fat diet. As a preventive strategy, lipid formulation could be optimized to limit these phenomena, notably regarding fatty acid profile and PL emulsifier content. Little is known about soybean polar lipid (SPL) consumption associated to oils rich in saturated FA vs. anti-inflammatory omega-3 FA such as α-linolenic acid on inflammation and metabolic endotoxemia. We then investigated in mice the effect of different synthetic diets enriched with two different oils, palm oil or flaxseed oil and containing or devoid of SPL on adipose tissue inflammation and endotoxin receptors. In both groups containing SPL, adipose tissue (WAT) increased compared with groups devoid of SPL and an induction of MCP-1 and LBP was observed in WAT. However, only the high-fat diet in which flaxseed oil was associated with SPL resulted in both higher WAT inflammation and higher circulating sCD14 in plasma. In conclusion, we have demonstrated that LPS transporters LBP and sCD14 and adipose tissue inflammation can be modulated by SPL in high fat diets differing in oil composition. Notably high-flaxseed oil diet exerts a beneficial metabolic impact, however blunted by PL addition. Our study suggests that nutritional strategies can be envisaged by optimizing dietary lipid sources in manufactured products, including fats/oils and polar lipid emulsifiers, in order to limit the inflammatory impact of palatable foods.

A critical assessment of transmethylation procedures for n-3 long-chain polyunsaturated fatty acid quantification of lipid classes

Lipid transmethylation methods described in the literature are not always evaluated with care so to insure that the methods are effective, especially on food matrix or biological samples containing polyunsaturated fatty acid (PUFA). The aim of the present study was to select a method suitable for all lipid species rich in long chain n-3 PUFA. Three published methods were adapted and applied on individual lipid classes. Lipid (trans)methylation efficiency was characterized in terms of reaction yield and gas chromatography (GC) analysis. The acid-catalyzed method was unable to convert triglycerides and sterol esters, while the method using an incubation at a moderate temperature was ineffective on phospholipids and sterol esters. On the whole only the method using sodium methoxide and sulfuric acid was effective on lipid classes taken individually or in a complex medium. This study highlighted the use of an appropriate (trans)methylation method for insuring an accurate fatty acid composition.

Effects on Fatty Acid Metabolism of a New Powdered Human Milk Fortifier Containing Medium-Chain Triacylglycerols and Docosahexaenoic Acid in Preterm Infants

Preterm infants require fortification of human milk (HM) with essential fatty acids (FA) to ensure adequate post-natal development. As part of a larger randomized controlled study, we investigated FA metabolism in a subset of 47 clinically stable preterm infants (birth weight ≤1500 g or gestational age ≤32 weeks). Infants were randomized to receive HM supplemented with either a new HM fortifier (nHMF; n = 26) containing 12.5 g medium-chain FA (MCFA), 958 mg linoleic acid (LA), 417 mg α-linolenic acid (ALA), and 157 mg docosahexaenoic acid (DHA) per 100 g of powder (in compliance with the latest guidelines) or a fat-free HMF (cHMF; n = 21). Plasma phospholipid (PL) and triacylglycerol (TAG), and red blood cell phosphatidylcholine (RBC-PC) and phosphatidylethanolamine (RBC-PE) FA profiles were assessed before and after 21 days of feeding. In the nHMF group, significantly increased levels of n-9 monounsaturated fatty acids were observed, formed most likely by elongation and desaturation of dietary saturated fatty acids present in HM. ALA fortification increased ALA assimilation into plasma TAG. Similarly, DHA fortification enriched the DHA content in RBC-PE, which, in this compartment, was not associated with lower arachidonic acid levels as observed in plasma TAG and phospholipids. RBC-PE, a reliable indicator of FA metabolism and accretion, was the most sensitive compartment in this study.

Transfatty Acids (TFAs) in Cord Blood and Cord Tissue, in France

Background: Recent studies suggest that dietary transfatty acids (TFAs) at relative high levels (i) increase the risk of coronary heart disease, (ii) inhibit the metabolism of linoleic acid and consequently increase requirement for essential fatty acids (EFAs). The aim of this prospective study was to estimate TFAs the placental transfer of TFAs to the foetus cord blood and cord tissues in France. Material: TFAs consumption was measured in 59 mother-foetus couples. TFAs transferring across the placenta were estimated by comparative measurement (Capillary Gaz Chromatography) of TFAs in mother’s blood lipids (n = 59), cord blood lipids and cord tissue plasma lipids (n = 25) cord red blood tissue (n = 25) and umbilical vessels (n = 15). Results-Discussion: TFA deposition in cord blood is 0.58% slightly lower than mother level. TFAs incorporation in total lips of cord show selectivity of transfer with lower 18:1 t in cord blood and preferential transfer of diene 18:2 tc in cord blood. There is competition between the 18:2 tc in cholesterol esters (CE) with the linolenic acid and a negative correlation in PLT of arterial tissues with the 18:2 tc and C20:4 n-6 or arachidonic acid (AA), then there is the same competition in PE of venous tissue. But there is no effect on growth in our population of term newborn. Conclusions: Our results confirm the placental TFAs transfer, a better incorporation in the fetus CE; we demonstrated a selective transfer for the 18:2 9 trans 12 cis (18:2 tc) and a negative correlation (r = -0.76) with the linoleic acid and AA (r = 0.98). This competition, and the presence of these TFAs in cord tissues, even at a low TFAs consumption, remind us to be a potential risk for the fetus concerning EFA metabolism and growth.

PO-0585 Effect Of Long Time Low Temperature Pasteurisation (ltlt) And Lyophilyzation On Fats Of Human Milk Banking (hmb)

Background Donor human milk (HM) was associated with slower growth in the early postnatal period. The macronutrient concentrations of HM could be influenced by the various processes used in human milk bank. The LTLT pasteurisation was known to slightly decrease protein and fat content of HMB. But The effect of the lyophilization was not described. Aims To Compare the lipids compositions between raw/LTLT/lyophilized HM. Methods This is a monocentric of 22 batches independent prospective study on HM. After Folch extraction, Total fat was determined gravimetrically. The fatty acid (FA), after direct transesterification, were separated by capillary gas chromatography with BPX 70 column. Statistical analysis were: apparied t test and/or T of Wilcoxon. Results Abstract PO-0585 Table 1 Raw/LTLT/Lyophylized HM HM Raw (n = 22) LTLT (n = 22) Lyophylized (n = 18) Total Lipids (g/l) 32,17* 31,31 30,87* Fatty Acids% Myristic 7.05 7.01 7.08 Palmitic 23,38 23,25 23,49 Oleic 30,79 31,24 31,14 Linoleic 9,27 9,26 9,28 linolenic 0,86 0,86 0,87 Arachidonic 0,39 0,39 0,41 DHA 0,24 0,24 0,26 Trans 0.92* 0.91 1* * p < 0.05 Conclusion Decrease of the fats was mainly observed after pasteurisation: difference (d=0.86 g/l) (p = 0.05, after Bonferroni correction it is non significant); the lyophylization preserved almost total lipids after LTLT (d=0.26 g/l NS). But the total effect of LTLT then lyophylization was a loss of 1.10 g/l of total lipids and significant. There was no significant difference between each of the fatty acids with both processes. LTLT Pasteurisation is not an optimal decontaminating HM process and we have to develop new techniques.