The effect of maternal omega-3 long-chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation during pregnancy and/or lactation on body fat mass in the offspring: a systematic review of animal studies

Maternal omega-3 LC-PUFA supplementation programs an improved bone mass in the offspring with a more pronounced effect in females than males at adulthood

Early balanced nutrition is vital in achieving optimal skeletal mass and its maintenance. Although a lower omega-6 (n-6): omega-3 (n-3) long-chain polyunsaturated fatty acid (LC-PUFA) ratio is strongly linked with bone health, its maternal effect in the programming of the offspring's skeleton remains to be elucidated. Plugged C57BL/6 mice were fed either n-3 LC-PUFA Enriched Diet (LED) or a control diet (C) throughout their gestation and lactation. Offspring born to both the groups were weaned onto C till 6, 12, and 24 weeks of their age. Offspring's skeleton metabolism and serum fatty acid composition was studied. In humans, seventy-five mother-female newborns pairs from term gestation were tested for their maternal LC-PUFA status relationships to venous cord blood bone biomarkers. Offspring of maternal LED supplemented mice exhibited a superior bone phenotype over C, more prominent in females than males. A lower serum n-6/n-3 LC-PUFA in the LED group offspring was strongly associated with blood biomarkers of bone metabolism. Sexual dimorphism evidenced had a strong correlation between offspring's LC-PUFA levels and bone turnover markers in serum. A higher potential for osteoblastic differentiation in both LED offspring genders and reduced osteoclastogenesis in females was cell-autonomous effect. The human cross-sectional study also showed a positive correlation between maternal n-3 PUFA and cord blood markers of bone formation in female newborns at birth. Maternal dietary n-6/ n-3 fat quality determines offspring's bone growth and development. Our data suggest that the skeleton of female offspring is likely to be more sensitive to this early exposure.

Maternal omega-3 fatty acid deficiency affects fetal thermogenic development and postnatal musculoskeletal growth in mice

Maternal omega-3 (n-3) polyunsaturated fatty acids (PUFAs) deficiency can affect offspring's adiposity and metabolism by modulating lipid and glucose metabolism. However, the impact of n-3 PUFA deficiency on the development of fetal thermogenesis and its consequences is not reported. Using an n-3 PUFA deficient mice, we assessed fetal interscapular brown adipose tissue (iBAT), body fat composition, insulin growth factor-1 (IGF-1), glucose transporters (GLUTs), and expression of lipid storage & metabolic proteins in the offspring. The n-3 PUFA deficiency did not change the pups' calorie intake, organ weight, and body weight. However, the offspring's skeletal growth was altered due to excess fat to lean mass, reduced tibia & femur elongation, dysregulated IGF-1 in the mother and pups (P< .05). Localization of uncoupling protein 1 (UCP1) in iBAT exhibited a reduced expression in the deficient fetus. Further, UCP1, GLUT1, GPR120 were downregulated while FABP3, ADRP, GLUT4 expressions were upregulated in the BAT of the deficient offspring (P< .05). The deficiency decreased endogenous conversion of the n-3 LCPUFAs from their precursors and upregulated SCD1, FASN, and MFSD2A mRNAs in the liver (P< .05). An altered musculoskeletal growth in the offspring is associated with impaired browning of the fetal adipose, dysregulated thermogenesis, growth hormone, and expression of glucose and fatty acid metabolic mediators due to maternal n-3 PUFA deficiency. BAT had higher metabolic sensitivity compared to WAT in n-3 PUFA deficiency. Maternal n-3 PUFA intake may prevent excess adiposity by modulating fetal development of thermogenesis and skeletal growth dynamics in the mice offspring.

Interactions between a polygenic risk score for plasma docosahexaenoic fatty acid concentration, eating behaviour, and body composition in children

BACKGROUND

The relationship between eating behaviour and current body weight has been described. However little is known about the effect of polyunsaturated fatty acids (PUFA) in this relationship. Genetic contribution to a certain condition is derived from a combination of small effects from many genetic variants, and polygenic risk scores (PRS) summarize these effects. A PRS based on a GWAS for plasma docosahexaenoic fatty acid (DHA) has been created, based on SNPs from 9 genes.

OBJECTIVE

To analyze the interaction between the PRS for plasma DHA concentration, body composition and eating behaviour (using the Children Eating Behaviour Questionnaire) in childhood.

SUBJECTS/METHODS

We analyzed a subsample of children from the Maternal, Adversity, Vulnerability and Neurodevelopment (MAVAN) cohort with PRS and measurements of eating behaviour performed at 4 years of age (n = 210), 6 y (n = 177), and body fat determined by bioelectric impedance at 4 y and 6 y or by air displacement plethysmography and dual-energy X-ray absorptiometry at 8 y (n = 42 and n = 37). PRS was based on the GWAS from Lemaitre et al. 2011 (p threshold = p < 5*10-6), and a median split created low and high PRS groups (high PRS = higher DHA level).

RESULTS

In ALSPAC children, we observed an association between PRS and plasma DHA concentration (β = 0.100, p < 0.01) and proportion (β = 0.107, p < 0.01). In MAVAN, there were interactions between PRS and body fat on pro-intake scores in childhood, in which low PRS and higher body fat were linked to altered behaviour. There were also interactions between PRS and pro-intake scores early in childhood on body fat later in childhood, suggesting that the genetic profile and eating behaviour influence the development of adiposity at later ages.

CONCLUSIONS

A lower PRS (lower plasma PUFA) can be a risk factor for developing higher body fat associated with non-adaptive eating behaviour in childhood; it is possible that the higher PRS (higher plasma PUFA) is a protective feature.

Adipose Tissue Dysfunctions in Response to an Obesogenic Diet Are Reduced in Mice after Transgenerational Supplementation with Omega 3 Fatty Acids

Obesity is characterized by profound alterations in adipose tissue (AT) biology, leading to whole body metabolic disturbances such as insulin resistance and cardiovascular diseases. These alterations are related to the development of a local inflammation, fibrosis, hypertrophy of adipocytes, and dysregulation in energy homeostasis, notably in visceral adipose tissue (VAT). Omega 3 (n-3) fatty acids (FA) have been described to possess beneficial effects against obesity-related disorders, including in the AT; however, the long-term effect across generations remains unknown. The current study was conducted to identify if supplementation with n-3 polyunsaturated FA (PUFA) for three generations could protect from the consequences of an obesogenic diet in VAT. Young mice from the third generation of a lineage receiving a daily supplementation (1% of the diet) with fish oil rich in eicosapentaenoic acid (EPA) or an isocaloric amount of sunflower oil, were fed a high-fat, high-sugar content diet for 4 months. We explore the transcriptomic adaptations in each lineage using DNA microarray in VAT and bioinformatic exploration of biological regulations using online databases. Transgenerational intake of EPA led to a reduced activation of inflammatory processes, perturbation in metabolic homeostasis, cholesterol metabolism, and mitochondrial functions in response to the obesogenic diet as compared to control mice from a control lineage. This suggests that the continuous intake of long chain n-3 PUFA could be preventive in situations of oversupply of energy-dense, nutrient-poor foods.

Perspective: Moving Toward Desirable Linoleic Acid Content in Infant Formula

Infant formula should provide the appropriate nutrients and adequate energy to facilitate healthy infant growth and development. If conclusive data on quantitative nutrient requirements are not available, the composition of human milk (HM) can provide some initial guidance on the infant formula composition. This paper provides a narrative review of the current knowledge, unresolved questions, and future research needs in the area of HM fatty acid (FA) composition, with a particular focus on exploring appropriate intake levels of the essential FA linoleic acid (LA) in infant formula. The paper highlights a clear gap in clinical evidence as to the impact of LA levels in HM or formula on infant outcomes, such as growth, development, and long-term health. The available preclinical information suggests potential disadvantages of high LA intake in the early postnatal period. We recommend performing well-designed clinical intervention trials to create clarity on optimal levels of LA to achieve positive impacts on both short-term growth and development and long-term functional health outcomes.

The evolutionary ecology of fatty-acid variation: Implications for consumer adaptation and diversification

The nutritional diversity of resources can affect the adaptive evolution of consumer metabolism and consumer diversification. The omega-3 long-chain polyunsaturated fatty acids eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) have a high potential to affect consumer fitness, through their widespread effects on reproduction, growth and survival. However, few studies consider the evolution of fatty acid metabolism within an ecological context. In this review, we first document the extensive diversity in both primary producer and consumer fatty acid distributions amongst major ecosystems, between habitats and amongst species within habitats. We highlight some of the key nutritional contrasts that can shape behavioural and/or metabolic adaptation in consumers, discussing how consumers can evolve in response to the spatial, seasonal and community-level variation of resource quality. We propose a hierarchical trait-based approach for studying the evolution of consumers' metabolic networks and review the evolutionary genetic mechanisms underpinning consumer adaptation to EPA and DHA distributions. In doing so, we consider how the metabolic traits of consumers are hierarchically structured, from cell membrane function to maternal investment, and have strongly environment-dependent expression. Finally, we conclude with an outlook on how studying the metabolic adaptation of consumers within the context of nutritional landscapes can open up new opportunities for understanding evolutionary diversification.

Omega-3 fats in pregnancy: could a targeted approach lead to better metabolic health for children?

The prevalence of childhood obesity is increasing worldwide, and the children of women who are obese during pregnancy are at greatest risk. This risk may be mediated by exaggeration of the normal insulin resistance of pregnancy. Omega-3 (n-3) fats are insulin sensitizing. Supplementation during pregnancy may reduce metabolic risk and adiposity in the children. Though results from animal studies are encouraging, completed clinical trials have not demonstrated this benefit. However, to our knowledge, previous studies have not targeted women who are overweight or obese while pregnant-the group at greatest risk for insulin resistance and most likely to benefit from n-3. In this narrative review, the importance of performing clinical trials restricted to women who are overweight or obese is discussed, as is the potential importance of n-3 dose, oil source and quality, and the timing of the intervention.

Evaluation of Maternal Dietary n-3 LCPUFA Supplementation as a Primary Strategy to Reduce Offspring Obesity: Lessons From the INFAT Trial and Implications for Future Research

Preclinical research suggests that early exposure to LCPUFAs is associated with offspring health outcomes, although evidence in humans is rather unclear. In 2006, we established the Impact of Nutritional Fatty acids during pregnancy and lactation on early human Adipose Tissue development (INFAT) study, a prospective randomized controlled intervention trial that examined whether decreasing the n-6/n-3 LCPUFA ratio during pregnancy and lactation influences offspring adipose tissue development in children up to 5 years. Our results indicate that maternal supplementation with n-3 LCPUFAs does not reduce offspring obesity risk, which is in line with recent publications. This perspective describes the challenges and lessons learned from our clinical trial. We discuss key findings and critically evaluate differences in study design, methodology, and analyses across similar intervention trials that may partly explain heterogeneous results. Summarizing evidence from human trials, we conclude that n-3 LCPUFA supplementation should not be recommended as a primordial strategy to prevent childhood obesity. Instead, it remains unknown whether n-3 LCPUFA supplementation could benefit high-risk subgroups and some vulnerable maternal/child populations. The perspectives offered herein are derived largely from insights gained from ours and similar n-3 LCPUFA intervention trials and help to provide direction for future research that examines the impact of maternal nutritional exposure on offspring health and disease outcomes.

Omega-6:Omega-3 Fatty Acid Ratio and Total Fat Content of the Maternal Diet Alter Offspring Growth and Fat Deposition in the Rat

Omega-3 long-chain polyunsaturated fatty acids (LCPUFA) have been shown to inhibit lipogenesis and adipogenesis in adult rats. Their possible early life effects on offspring fat deposition, however, remain to be established. To investigate this, female Wistar rats (n = 6–9 per group) were fed either a 9:1 ratio of linoleic acid (LA) to alpha-linolenic acid (ALA) or a lower 1:1.5 ratio during pregnancy and lactation. Each ratio was fed at two total fat levels (18% vs. 36% fat w/w) and offspring were weaned onto standard laboratory chow. Offspring exposed to a 36% fat diet, irrespective of maternal dietary LA:ALA ratio, were lighter (male, 27 g lighter; female 19 g lighter; p < 0.0001) than those exposed to an 18% fat diet between 3 and 8 weeks of age. Offspring exposed to a low LA (18% fat) diet had higher proportions of circulating omega-3 LCPUFA and increased gonadal fat mass at 4 weeks of age (p < 0.05). Reduced Srebf1 mRNA expression of hepatic (p < 0.01), gonadal fat (p < 0.05) and retroperitoneal fat (p < 0.05) tissue was observed at 4 weeks of age in male and female offspring exposed to a 36% fat diet, and hepatic Srebf1 mRNA was also reduced in male offspring at 8 weeks of age (p < 0.05). Thus, while offspring fat deposition appeared to be sensitive to both maternal dietary LA:ALA ratio and total fat content, offspring growth and lipogenic capacity of tissues appeared to be more sensitive to maternal dietary fat content.

Docosahexaenoic Acid (DHA, C22:6, ω-3) Composition of Milk and Mammary Gland Tissues of Lactating Mother Rats Is Severely Affected by Lead (Pb) Exposure

Docosahexaenoic acid (DHA, C22:6, ω-3), an ω-3 polyunsaturated fatty acid (PUFA), is critical for brain growth, development, and cognitive ability. It is consumed by offspring via milk during lactation. However, the toxic heavy metal lead (Pb) readily passes into the mammary glands of mother animals and then to offspring through milk. Here, we investigated whether DHA composition of milk and mammary gland tissues is affected by Pb exposure. Mother rats were exposed to Pb via drinking water (0.1%). The fatty acid profile and levels of reduced glutathione (GSH), lipid peroxide (LPO), and pro-inflammatory TNF-α in milk and mammary tissues were measured. Levels of DHA and antioxidant GSH decreased (P < 0.05), while LPO and TNF-α levels increased (P < 0.05) both in milk and mammary tissues. Our results suggest that toxic Pb exposure can upset the level of milk DHA, which may affect brain growth and development, and hence cognitive ability in adulthood and later life.

The effect of maternal dietary fat content and n-6:n-3 ratio on offspring growth and hepatic gene expression in the rat

n-6 Fatty acids have been shown to exert pro-adipogenic effects, whereas n-3 fatty acids work in opposition. Increasing intakes of linoleic acid (LA; n-6) v. α-linolenic acid (ALA; n-3) in Western diets has led to the hypothesis that consumption of this diet during pregnancy may be contributing to adverse offspring health. This study investigated the effects of feeding a maternal dietary LA:ALA ratio similar to that of the Western diet (9:1) compared with a proposed 'ideal' ratio (about 1:1·5), at two total fat levels (18 v. 36 % fat, w/w), on growth and lipogenic gene expression in the offspring. Female Wistar rats were assigned to one of the four experimental groups throughout gestation and lactation. Offspring were culled at 1 and 2 weeks of age for sample collection. Offspring of dams consuming a 36 % fat diet were approximately 20 % lighter than those exposed to an 18 % fat diet (P < 0·001). Male, but not female, liver weight at 1 week was approximately 13 % heavier and had increased glycogen (P < 0·05), in offspring exposed to high LA (P < 0·01). Hepatic expression of lipogenic genes suggested an increase in lipogenesis in male offspring exposed to a 36 % fat maternal diet and in female offspring exposed to a low-LA diet, via increases in the expression of fatty acid synthase and sterol regulatory element-binding protein. Sexually dimorphic responses to altered maternal diet appeared to persist until 2 weeks of age. In conclusion, whilst maternal total fat content predominantly affected offspring growth, fatty acid ratio and total fat content had sexually dimorphic effects on offspring liver weight and composition.

Nutritional Models of Type 2 Diabetes Mellitus

In order to better understand the events that precede and precipitate the onset of type 2 diabetes (T2DM), several nutritional animal models have been developed. These models are generated by manipulating the diet of either the animal itself, or its mother during her pregnancy, and in comparison to traditional genetic and knock out models, have the advantage that they more accurately reflect the etiology of human T2DM. This chapter will discuss some of the most widely used nutritional models of T2DM: Diet-induced obesity (DIO) in adult rodents, and studies of offspring of mothers fed a low-protein, high-fat and/or high-sugar diet during pregnancy and/or lactation. Several common mechanisms have been identified through which these nutritional manipulations can lead to metabolic disease, including pancreatic beta-cell dysfunction, impaired insulin signaling in skeletal muscle, and the excess accumulation of visceral adipose tissue and consequent deposition of nonesterified fatty acids in peripheral tissues. In addition, there is an emerging concept that obesity/poor quality diets result in increased production and release of pro-inflammatory cytokines from adipose tissue leading to a state of chronic low-grade inflammation, and that this is likely to represent an important link between obesity/diet and metabolic dysfunction. The following chapter will discuss the most common nutritional models of T2DM in experimental animals, their application, and relationship to human etiology, and will highlight the important insights these models have provided into the pathogenesis of T2DM.

The Effect of Dietary Oil Type and Energy Intake in Lactating Sows on the Fatty Acid Profile of Colostrum and Milk, and Piglet Growth to Weaning

This study investigated the effect of salmon oil in lactating sow diets and offering these diets in a phased dietary regimen to increase the energy density of the diet in late lactation. Sow and piglet productivity to weaning, the fatty acid profile of milk, piglet blood and tissues at weaning were the main parameters measured. Multiparous sows (n = 100) (Landrace × Large White) were offered dietary treatments from day 105 of gestation until weaning. Dietary treatments (2 × 2 factorial) included oil type (soya or salmon oil) and dietary regimen (Flat 14.5 MJ/kg DE diet offered until weaning or Phased 14.5 MJ/kg DE diet offered to day 14 of lactation then a second diet containing 15.5 MJ/kg DE offered from day 15 until weaning). Salmon oil inclusion increased the total proportion of n-3 fatty acids in colostrum (p < 0.001), milk (p < 0.001), piglet plasma (p < 0.01), adipose (p < 0.001), liver (p < 0.001) and muscle (p < 0.001). Increasing sow dietary energy level in late lactation increased the total n-3 fatty acids in milk (p < 0.001), piglet adipose (p < 0.01) and piglet muscle (p < 0.05). However, piglet growth to weaning did not improve.

Maternal and postnatal high-fat diets with high ω6 : ω3 ratios affect the reproductive performance of male offspring in the mouse

High-fat diets (HFDs) are an acknowledged risk factor for male subfertility, but the underlying mechanisms remain unclear. In the present study we compared the effects of two HFDs with different ω6:ω3 ratios, one enriched with soy oil (SOD; ω6:ω3=9.62) and another enriched with sunflower oil (SFOD; ω6:ω3=51.55), with those of a commercial diet (CD; ω6:ω3=19.87), supplied from pregnancy to adulthood, on morphometric parameters and reproductive performance in adult male mice (recommended ω6:ω3 for rodents=1-6). Bodyweight was significantly higher in the SFOD than CD group, and relative testicular weight was significantly lower in the SFOD than the other two groups. SFOD altered sperm performance: it reduced sperm viability (mean±s.e.m.; 76.00±1.35% vs 82.50±1.45% and 80.63±1.00% in the SFOD vs CD and SOD groups respectively; P<0.05) and increased the percentage of immature spermatozoa (71.88±7.17% vs 51.38±5.87% and 48.00±5.72% in the SFOD vs CD and SOD groups respectively; P<0.05). The epididymal ω6:ω3 ratio was higher in the SFOD versus CD and SOD groups, whereas the unsaturation index was higher in the SOD and SFOD groups than in CD group. Sperm membrane integrity was diminished in both the SOD and SFOD groups, but there was no difference in sperm reactive oxygen species production in these two groups compared with the CD group. The fertilisation rate was lower in the SFOD compared with the CD and SOD groups. In conclusion, although both HFDs affected sperm quality, the fertilising ability was more altered by the excessive dietary ω6:ω3 ratio than by the net ω6 content.

Maternal and Postnatal Supplementation of Fish Oil Improves Metabolic Health of Mouse Male Offspring

OBJECTIVE

Over half of American women of childbearing age have either obesity or overweight. Hence, maternal programming through diet is critical for prevention of diseases in the offspring. Clinical trials with fish oil (FO) report various health benefits; however, it remains unclear whether maternal and postnatal consumption of FO protects offspring from adverse effects of consuming a high-fat (HF) diet.

METHODS

Female mice were fed HF diets supplemented without (HF) or with FO from 8 weeks before pregnancy through lactation. A low-fat (LF) diet was included as a control diet. After weaning, male offspring from HF or FO dams were either continued on their respective diet (HF-HF and FO-FO) or switched to the other diet (HF-FO and FO-HF) and compared with LF. Phenotypic and mechanistic studies were performed.

RESULTS

FO-FO offspring demonstrated significantly higher glucose clearance and insulin sensitivity compared with other pups fed the HF diet (P < 0.05). Furthermore, FO-FO pups had lower adiposity, inflammation, and fat deposition in the liver, consistent with reduced markers of hepatic lipogenesis and increased hepatic lipid oxidation.

CONCLUSIONS

Supplementation of FO during pregnancy and early life is more beneficial than treating with FO either during pregnancy or in pups.

Maternal BMI, Mid-pregnancy Fatty Acid Concentrations,and Perinatal Outcomes

PURPOSE

Maternal body mass index (BMI) and systemic fatty acid (FA) concentrations affect inflammatory balance in pregnancy and play a key role in fetal growth and well-being. Little is known about how maternal BMI may affect the association between key FA concentrations and neonatal outcomes. The objective of this study was to examine the associations between the maternal omega (n)6:n3 FA ratio and neonatal outcomes according to maternal pre-pregnancy BMI category.

METHODS

This study is a secondary analysis of the Maternal-Fetal Medicine Units Network randomized controlled trial of omega-3 FA supplementation to prevent recurrent preterm birth. At consent (16-22 weeks of pregnancy), women were randomized to either the intervention arm (2g of n3 FAs) or the control arm (placebo). For the present analysis, the primary exposure was the ratio of proinflammatory to anti-inflammatory (n6:n3) FAs at 25 to 28 weeks of pregnancy. The primary outcome was fetal growth as measured by using birth-weight-for-gestational-age z score, birth-length-for-gestational-age z score, and head-circumference-for-gestational-age z score. BMI categories were defined as lean (18.5-24.9 kg/m²) and overweight/obese (OWOB) (≥25.0 kg/m²). Final analysis was stratified according to BMI and adjusted for education, race, parity, smoking status, total fish intake at the time of the blood draw, and number of days in the study at the time of delivery.

FINDINGS

A total of 440 participants were included in this analysis; 49% were lean, and 51% were OWOB. After adjustment for covariates, a higher maternal n6:n3 FA ratio was associated with impaired fetal growth (birth-weight-for-gestational-age z score, β = -0.04 per unit increase in n6:n3; 95% CI, -0.07 to -0.01), 1day shorter length of gestation (β = -0.14 week; 95% CI, -0.27 to -0.01), higher incidence of neonatal respiratory distress syndrome (odds ratio, 1.37; 95% CI, 1.04 to 1.80), and increased length of neonatal hospital stay (β = 0.29 day; 95% CI, 0.003 to 0.58) in OWOB, but not lean, participants.

IMPLICATIONS

Higher maternal inflammation during pregnancy, as measured by using the n6:n3 FA ratio, may be a marker of adverse perinatal and neonatal outcomes, particularly among OWOB women.

Effect of fish oil supplementation in pregnancy on bone, lean, and fat mass at six years: randomised clinical trial

OBJECTIVE

To examine the effect of supplementation with n-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) in pregnancy on anthropometry and body composition in offspring.

DESIGN

Double blinded, randomised controlled trial.

SETTING

Copenhagen Prospective Studies on Asthma in Childhood2010 cohort.

PARTICIPANTS

736 pregnant women and their offspring.

INTERVENTION

n-3 LCPUFA (fish oil) or control (olive oil) daily from pregnancy week 24 until one week after birth.

MAIN OUTCOME MEASURES

Height/length, weight, head, and waist measurements and body composition from dual energy x ray absorptiometry (all pre-specified secondary endpoints of the n-3 LCPUFA trial; the primary outcome for the trial was persistent wheeze/asthma).

RESULTS

The mean body mass index (BMI) z score was increased between age 0 and 6 years in the fish oil supplementation group compared with the control group (0.14 (95% confidence interval 0.04 to 0.23); P=0.006). At 6 years, supplementation was associated with a higher BMI z score (0.19 (0.06 to 0.32); P=0.004), a higher weight/height (3.48 (0.38 to 6.57) g/cm; P=0.03), and a larger waist circumference (0.6 (0.0 to 1.2) cm; P=0.04) but not a higher proportion of obese children, using International Obesity Task Force grades. The dual energy x ray absorptiometry scan at age 6 years showed a higher total mass (395.4 (86.6 to 704.3) g; P=0.01) in the supplementation versus the control group, explained by a higher lean mass (280.7 (98.9 to 462.4) g; P=0.002), a higher bone mineral content (10.3 (2.3 to 18.1) g; P=0.01), and a non-significantly higher fat mass (116.3 (-92.9 to 325.5) g; P=0.28), but no differences were seen in total body fat or lean mass percentage.

CONCLUSION

Fish oil supplementation from the 24th week of pregnancy led to a higher BMI in the offspring from 0 to 6 years of age but not an increased risk of obesity at age 6. The body composition at age 6 years in children given fish oil supplementation was characterised by a proportional increase in lean, bone, and fat mass suggesting a general growth stimulating effect of n-3 LCPUFA.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00798226.

Maternal omega-3 fatty acids regulate offspring obesity through persistent modulation of gut microbiota

BACKGROUND

The early-life gut microbiota plays a critical role in host metabolism in later life. However, little is known about how the fatty acid profile of the maternal diet during gestation and lactation influences the development of the offspring gut microbiota and subsequent metabolic health outcomes.

RESULTS

Here, using a unique transgenic model, we report that maternal endogenous n-3 polyunsaturated fatty acid (PUFA) production during gestation or lactation significantly reduces weight gain and markers of metabolic disruption in male murine offspring fed a high-fat diet. However, maternal fatty acid status appeared to have no significant effect on weight gain in female offspring. The metabolic phenotypes in male offspring appeared to be mediated by comprehensive restructuring of gut microbiota composition. Reduced maternal n-3 PUFA exposure led to significantly depleted Epsilonproteobacteria, Bacteroides, and Akkermansia and higher relative abundance of Clostridia. Interestingly, offspring metabolism and microbiota composition were more profoundly influenced by the maternal fatty acid profile during lactation than in utero. Furthermore, the maternal fatty acid profile appeared to have a long-lasting effect on offspring microbiota composition and function that persisted into adulthood after life-long high-fat diet feeding.

CONCLUSIONS

Our data provide novel evidence that weight gain and metabolic dysfunction in adulthood is mediated by maternal fatty acid status through long-lasting restructuring of the gut microbiota. These results have important implications for understanding the interaction between modern Western diets, metabolic health, and the intestinal microbiome.

Sex-specific Alterations in Serology and the Expression of Liver FATP4 Protein in Offspring Exposed to High-Fat Diet during Pregnancy and/or Lactation

Changes in dietary composition will have a significant impact on the nutritional status of the mother and the offspring. To examine the relevant hormone level changes during lactation and the expression of fatty acid transporters in the placenta and liver under the condition of a high-fat (HF) diet, we established HF animal models and conducted a cross-fostering program to mimic the shift in diet. On gestation day (GD)18, the weight of placenta in the HF group was significantly higher than that in the control group (p < 0.05). HF-fed male pups had a significantly lower serum insulin level, but the same phenomenon was not found in females. On the contrary, serum triacylglycerol (TAG) level presented a tendency to decrease only in female offspring. Oil red O staining showed lipid accumulation in the HF diet offspring livers. The mRNA levels of FATP4 in the placenta in the HF diet group were significantly upregulated compared to the control diet group (p < 0.05). High-fat diet (HFD) consumption also altered the liver mRNA levels of FATP4, SREBP-1, and SCD-1 in the male offspring, while the changes in protein levels of FATP4 were not observed in either sex. In conclusion, maternal HF diet has a profound impact on offspring growth, metabolism, and the risk of metabolic disorders, which would depend on the exposure period of pregnancy and lactation.

Low Neonatal Plasma n-6/n-3 PUFA Ratios Regulate Offspring Adipogenic Potential and Condition Adult Obesity Resistance

Adipose tissue expansion progresses rapidly during postnatal life, influenced by both prenatal maternal factors and postnatal developmental cues. The ratio of omega-6 (n-6) relative to n-3 polyunsaturated fatty acids (PUFAs) is believed to regulate perinatal adipogenesis, but the cellular mechanisms and long-term effects are not well understood. We lowered the fetal and postnatal n-6/n-3 PUFA ratio exposure in wild-type offspring under standard maternal dietary fat amounts to test the effects of low n-6/n-3 ratios on offspring adipogenesis and adipogenic potential. Relative to wild-type pups receiving high perinatal n-6/n-3 ratios, subcutaneous adipose tissue in 14-day-old wild-type pups receiving low n-6/n-3 ratios had more adipocytes that were smaller in size; decreased Pparγ2, Fabp4, and Plin1; several lipid metabolism mRNAs; coincident hypermethylation of the PPARγ2 proximal promoter; and elevated circulating adiponectin. As adults, offspring that received low perinatal n-6/n-3 ratios were diet-induced obesity (DIO) resistant and had a lower positive energy balance and energy intake, greater lipid fuel preference and non-resting energy expenditure, one-half the body fat, and better glucose clearance. Together, the findings support a model in which low early-life n-6/n-3 ratios remodel adipose morphology to increase circulating adiponectin, resulting in a persistent adult phenotype with improved metabolic flexibility that prevents DIO.

Fish oil supplementation to rats fed high-fat diet during pregnancy prevents development of impaired insulin sensitivity in male adult offspring

We examined whether maternal fish oil supplementation during pregnancy could prevent development of insulin resistance in adult male offspring of rat dams fed a high-fat diet. Time-mated Sprague-Dawley rat dams were randomised into four treatment groups: Con-Con, dams fed a control diet (fat: 15% kcal) and administered water by gavage; Con-FO, control diet with unoxidised fish oil by gavage; HF-Con, high-fat diet (fat: 45% kcal) and water by gavage; and HF-FO, high-fat diet and unoxidised fish oil by gavage. Dams were fed the allocated diet ad libitum during pregnancy and lactation, but daily gavage occurred only during pregnancy. After weaning, male offspring consumed a chow diet ad libitum until adulthood. Maternal high-fat diet led to increased food consumption, adiposity, systolic blood pressure, and triglycerides and plasma leptin in adult HF-Con offspring. HF-Con offspring also exhibited lower insulin sensitivity than Con-Con rats. Male offspring from HF-FO group were similar to HF-Con regarding food consumption and most metabolic parameters. However, insulin sensitivity in the HF-FO group was improved relative to the HF-Con offspring. Supplementation with unoxidised n-3 PUFA rich oils in the setting of a maternal obesogenic diet improved insulin sensitivity, but had no impact on body composition of adult male offspring.

An Increased Dietary Supply of Medium-Chain Fatty Acids during Early Weaning in Rodents Prevents Excessive Fat Accumulation in Adulthood

Medium-chain fatty acids (MCFA) are a directly and readily absorbed source of energy. Exposure early-in-life to increased MCFA levels might affect development and impact (lipid) metabolism later in life. We tested whether an increased MCFA intake early-in-life positively affects adult body composition and metabolic status when challenged by a western-style diet (WSD). Male offspring of C57Bl/6j mice and Wistar rats were fed a control diet (CTRL; 10 w% fat, 14% MCFA) or a medium-chain triglycerides (MCT) diet with 20% MCFA until postnatal (PN) day 42, whereupon animals were fed a WSD (10 w% fat) until PN day 98. Body composition was monitored by Dual Energy X-ray Absorptiometry (DEXA). In rats, glucose homeostasis was assessed by glucose tolerance test (GTT) and insulin tolerance test (ITT); in mice, the HOmeostasis Model Assessment of Insulin Resistance (HOMA-IR) was calculated. At autopsy on PN day 98, plasma lipid profiles, glucose, insulin, and adipokines were measured; organs and fat pads were collected and the adipocyte size distribution was analysed. Milk analysis in mice showed that the maternal MCT diet was not translated into milk, and pups were thus only exposed to high MCT levels from early weaning onward: PN day 16 until 42. Mice exposed to MCT showed 28% less fat accumulation vs. CTRL during WSD. The average adipocyte cell size, fasting plasma triglycerides (TG), and leptin levels were reduced in MCT mice. In rats, no effects were found on the adult body composition, but the adipocyte cell size distribution shifted towards smaller adipocytes. Particularly mice showed positive effects on glucose homeostasis and insulin sensitivity. Increased MCFA intake early-in-life protected against the detrimental effects of an obesogenic diet in adulthood.

Effects of different n-6 to n-3 polyunsaturated fatty acids ratio on reproductive performance, fecal microbiota and nutrient digestibility of gestation-lactating sows and suckling piglets

This study was conducted to evaluate the effects of dietary ratios of n-6:n-3 polyunsaturated fatty acids (PUFA) on reproductive performance, fecal microbiota and nutrient digestibility of gestation-lactating sows and suckling piglets. Fifteen primiparous sows (Landrace × Yorkshire) were randomly allotted into three treatments. Fed diets contained different ratios of n-6:n-3 PUFA, including 20:1, 15:1 and 10:1. No differences were detected among the treatments for average daily feed intake (ADFI) of sows and the back fat levels during lactation (P > 0.05). Body weight (BW) loss of sows after farrowing to weanling was greater in the 10:1 treatment compared with 15:1 or 20:1 (P < 0.05). In piglets, a great significant difference for BW was observed at 4 weeks (P < 0.01). Furthermore, average daily gain (ADG) of piglets in the 10:1 treatment was higher (P < 0.05). No difference was observed among treatments in nutrient digestibility of sows (P > 0.05). A great significant difference for fecal microbiota was in the 10:1 treatment compared with 20:1 and 15:1 treatments (P < 0.01). In conclusion, altering the ratio of n-6:n-3 PUFA in gestation-lactating sow diet had no difference on nutrient digestibility in gestation-lactating sows, but it can partially improve reproductive performance.

The impact of maternal obesity on inflammatory processes and consequences for later offspring health outcomes

Obesity is a global epidemic, affecting both developed and developing countries. The related metabolic consequences that arise from being overweight or obese are a paramount global health concern, and represent a significant burden on healthcare systems. Furthermore, being overweight or obese during pregnancy increases the risk of offspring developing obesity and other related metabolic complications in later life, which can therefore perpetuate a transgenerational cycle of obesity. Obesity is associated with a chronic state of low-grade metabolic inflammation. However, the role of maternal obesity-mediated alterations in inflammatory processes as a mechanism underpinning developmental programming in offspring is less understood. Further, the use of anti-inflammatory agents as an intervention strategy to ameliorate or reverse the impact of adverse developmental programming in the setting of maternal obesity has not been well studied. This review will discuss the impact of maternal obesity on key inflammatory pathways, impact on pregnancy and offspring outcomes, potential mechanisms and avenues for intervention.

Modification of the fatty acid composition of an obesogenic diet improves the maternal and placental metabolic environment in obese pregnant mice

Peri-conceptional exposure to maternal obesogenic nutrition is associated with in utero programming of later-life overweight and metabolic disease in the offspring. We aimed to investigate whether dietary intervention with a modified fatty acid quality in an obesogenic high-calorie (HC) diet during the preconception and gestational phases can improve unfavourable effects of an adipogenic maternal environment. In NMRI mice, peri-conceptional and gestational obesity was induced by feeding a HC diet (controls), and they were compared with dams on a fat-modified (Fat-mod) HC diet of the same energy content but enriched with medium-chain fatty acids (MCFAs) and adjusted to a decreased ratio of n-6 to n-3 long-chain polyunsaturated fatty acids (LC-PUFAs). Effects on maternal and placental outcomes at delivery (day 17.5 post coitum) were investigated. Despite comparable energy assimilation between the two groups of dams, the altered fatty acid composition of the Fat-mod HC diet induced lower maternal body weight, weights of fat depots, adipocyte size, and hepatic fat accumulation compared to the unmodified HC diet group. Further, there was a trend towards lower fasting glucose, insulin and leptin concentrations in dams fed the Fat-mod HC diet. Phenotypic changes were accompanied by inhibition of transcript and protein expression of genes involved in hepatic de novo lipogenesis comprising PPARG2 and its target genes Fasn, Acaca, and Fabp4, whereas regulation of other lipogenic factors (Srebf1, Nr1h3, Abca1) appeared to be more complex. The modified diet led to a sex-specific placental response by upregulating PPARG-dependent fatty acid transport gene expression in female versus male placentae. Qualitative modification of the fatty acid spectrum of a high-energy maternal diet, using a combination of both MCFAs and n-3 LC-PUFAs, seems to be a promising interventional approach to ameliorate the adipogenic milieu of mice before and during gestation.

Maternal plasma PUFA concentrations during pregnancy and childhood adiposity: the Generation R Study

BACKGROUND

Maternal polyunsaturated fatty acid (PUFA) concentrations during pregnancy may have persistent effects on growth and adiposity in the offspring. A suboptimal maternal diet during pregnancy might lead to fetal cardiometabolic adaptations with persistent consequences in the offspring.

OBJECTIVE

We examined the associations of maternal PUFA concentrations during pregnancy with childhood general and abdominal fat-distribution measures.

DESIGN

In a population-based, prospective cohort study of 4830 mothers and their children, we measured maternal second-trimester plasma n-3 (ω-3) and n-6 (ω-6) PUFA concentrations. At the median age of 6.0 y (95% range: 5.6, 7.9 y), we measured childhood body mass index (BMI), the fat mass percentage, and the android:gynoid fat ratio with the use of dual-energy X-ray absorptiometry and measured the preperitoneal abdominal fat area with the use of ultrasound. Analyses were adjusted for maternal and childhood sociodemographic- and lifestyle-related characteristics.

RESULTS

We observed that higher maternal total n-3 PUFA concentrations, and specifically those of eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid, were associated with a lower childhood total-body fat percentage and a lower android:gynoid fat mass ratio (P< 0.05) but not with childhood BMI and the abdominal preperitoneal fat mass area. Higher maternal total n-6 PUFA concentrations, and specifically those of dihomo-γ-linolenic acid, were associated with a higher childhood total-body fat percentage, android:gynoid fat mass ratio, and abdominal preperitoneal fat mass area (P< 0.05) but not with childhood BMI. In line with these findings, a higher maternal n-6:n-3 PUFA ratio was associated with higher childhood total-body and abdominal fat mass.

CONCLUSIONS

Lower maternal n-3 PUFA concentrations and higher n-6 PUFA concentrations during pregnancy are associated with higher body fat and abdominal fat in childhood. Additional studies are needed to replicate these observations and to explore the causality, the underlying pathways, and the long-term cardiometabolic consequences.

Influence of Maternal and Postweaning Linseed Dietary Supplementation on Growth Rate, Lipid Profile, and Meat Quality Traits of Light Sarda Lambs

The effects of dietary extruded linseed (EL) on growth performance, meat quality, and lipid profile of Semimembranosus and Longissimus lumborum muscles of 81 Sarda lambs were studied in a 3 × 3 design: EL content (0%, 10%, and 20%) of maternal dietary concentrate fed from 20 d to parturition to 60 d of lactation and EL content (0%, 10%, 20%) of lamb concentrate fed after weaning for 30 d. The basal diet was composed of alfalfa and meadow hay during pregnancy and alfalfa hay during lactation. At slaughter, carcass and meat quality were evaluated. Sensory quality of Semimembranosus from 0% and 20% EL lambs was assessed. Both maternal and postweaning diets affected growth performance, with higher body weights recorded with the 10% EL concentrate. Carcass and meat quality were not affected by diet. Saturated and monounsaturated FA decreased and n-3 polyunsaturated FA increased with increasing EL content in lamb diet. An increase in vaccenic and rumenic acid was associated with the EL content of the maternal diet. Both diets increased the n-6/n-3 FA ratio. No differences in acceptability were detected by consumers among groups. It is concluded that EL supplementation and early life nutrition can influence performance and FA metabolism in growing lambs.

The Effect of Marine Derived n-3 Fatty Acids on Adipose Tissue Metabolism and Function

Adipose tissue function is key determinant of metabolic health, with specific nutrients being suggested to play a role in tissue metabolism. One such group of nutrients are the n-3 fatty acids, specifically eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). Results from studies where human, animal and cellular models have been utilised to investigate the effects of EPA and/or DHA on white adipose tissue/adipocytes suggest anti-obesity and anti-inflammatory effects. We review here evidence for these effects, specifically focusing on studies that provide some insight into metabolic pathways or processes. Of note, limited work has been undertaken investigating the effects of EPA and DHA on white adipose tissue in humans whilst more work has been undertaken using animal and cellular models. Taken together it would appear that EPA and DHA have a positive effect on lowering lipogenesis, increasing lipolysis and decreasing inflammation, all of which would be beneficial for adipose tissue biology. What remains to be elucidated is the duration and dose required to see a favourable effect of EPA and DHA in vivo in humans, across a range of adiposity.

Do fatty acids affect fetal programming?

BACKGROUND

In this study discussed the primary and regulatory roles of fatty acids, and investigated the affects of fatty acids on metabolic programming.

METHODS

Review of the literature was carried out on three electronic databases to assess the roles of fatty acids in metabolic programming. All abstracts and full-text articles were examined, and the most relevant articles were selected for screening and inclusion in this review.

RESULTS

The mother's nutritional environment during fetal period has important effects on long term health. Fatty acids play a primary role in growth and development. Alterations in fatty acid intake in the fetal period may increase the risk of obesity and metabolic disorders in later life. Maternal fatty acid intakes during pregnancy and lactation are passed to the fetus and the newborn via the placenta and breast milk, respectively. Imbalances in fatty acid intake during the fetal period change the fatty acid composition of membrane phospholipids, which can cause structural and functional problems in cells. Additionally, the metabolic and neuroendocrine environments of the fetus and the newborn play key roles in the regulation of energy balance.

CONCLUSIONS

Imbalances in fatty acid intake during pregnancy and lactation may result in permanent changes in appetite control, neuroendocrine function and energy metabolism in the fetus, leading to metabolic programming. Further studies are needed to determine the role of fatty acid intake in metabolic programming.

Reduced linoleic acid intake in early postnatal life improves metabolic outcomes in adult rodents following a Western-style diet challenge

The global increase in dietary n-6 polyunsaturated fatty acid (PUFA) intake has been suggested to contribute to the rise in obesity incidence. We hypothesized that reduced n-6 PUFA intake during early postnatal life improves adult body composition and metabolic phenotype upon a Western diet challenge. Male offspring of C57Bl/6j mice and Wistar rats were subjected to a control diet (CTRL; 3.16 En% linoleic acid [LA]) or a low n-6 PUFA diet (low LA; 1.36 En% LA) from postnatal days (PNs) 2 to 42. Subsequently, all animals were switched to a Western-style diet (2.54 En% LA) until PN98. We monitored body composition by dual-energy x-ray absorptiometry and glucose homeostasis by an intravenous glucose and insulin tolerance test in rats and by the homeostasis model assessment of insulin resistance (HOMA-IR) in mice. At PN98, plasma lipids, glucose, insulin, and adipokines were measured and adipocyte number and size were analyzed. In mice, the postnatal low-LA diet decreased fat accumulation during the adult Western-style diet challenge (-27% compared with CTRL, P < .001). Simultaneously, it reduced fasting triglyceride levels and lowered fasting resistin and leptin levels. In rats, the low-LA diet did not affect adult body composition, but decreased the number of retroperitoneal adipocytes and increased the number of large adipocytes. In conclusion, lowering dietary n-6 PUFA intake in early life protected against detrimental effects of an obesogenic diet in adulthood on metabolic homeostasis and fat mass accumulation.

Rapid and selective manipulation of milk fatty acid composition in mice through the maternal diet during lactation

Dietary fatty acid (FA) composition in early postnatal life can modulate growth and development and later metabolic health. Investigating programming effects of early dietary FA manipulations in rodents may be stressful and complicated due to the need of artificial feeding techniques. It is largely unknown to what extent breast milk (BM) FA composition can be directly manipulated by the diet. We exposed dams to different dietary FA compositions from postnatal day (PN) 2 until PN28. Dams with litters were randomly assigned to control (CTRL), high-medium-chain FA (MCFA), low-linoleic acid (LowLA), high-n-3 long-chain PUFA (n-3LCP) or high-n-3LCP and MCFA (n-3LCP/MCFA) diets, and diets were continued after weaning until PN28. FA compositions were determined in feeds, milk and in erythrocytes. BM MCFA content was independent from dietary MCFA intake. In contrast, the LowLA diet reduced BM LA content by about 50 % compared with the CTRL diet at PN7. BM of dams fed the n-3LCP or n-3LCP/MCFA diet contained about 6-fold more n-3 LCP than BM of the dams fed the CTRL diet at PN7. These changes in milk FA composition established after 5 d of dietary exposure did not further change over the lactation period. At PN28, the erythrocyte FA composition of the male pups correlated with analysed milk FA profiles. In conclusion, manipulation of the diet of lactating mice can strongly and rapidly affect BM FA composition, in particular of n-6 LA and n-3 LCP. Our present findings will facilitate mechanistic studies on the programming of adult metabolic health by dietary FA in the early postnatal period via direct and selective manipulation of the maternal diet.

Impact of maternal obesity on offspring adipose tissue: lessons for the clinic

Maternal obesity is a major risk factor for the subsequent development of obesity and Type 2 diabetes in the child. This relationship appears to be driven largely by the exposure of the fetus to an increased nutrient supply during critical periods of development, which results in persistent changes in the structure and function of key systems involved in the regulation of energy balance, appetite and fat deposition. One of the key targets is the fat cell, or adipocyte, in which prenatal overnutrition programs a heightened capacity for fat storage. The increasing prevalence of maternal obesity has led to an urgent need for strategies to break the resulting intergenerational cycle of obesity and metabolic disease. This review will discuss the relationship between maternal obesity and poor metabolic health of the offspring, with a particular focus on the involvement of adipose tissue, recent clinical studies examining potential strategies for intervention and priority areas for further research.

Interaction of diet and the masou salmon Δ5-desaturase transgene on Δ6-desaturase and stearoyl-CoA desaturase gene expression and N-3 fatty acid level in common carp (Cyprinus carpio)

The masou salmon Δ5-desaturase-like gene (D5D) driven by the common carp β-actin promoter was transferred into common carp (Cyprinus carpio) that were fed two diets. For P1 transgenic fish fed a commercial diet, Δ6-desaturase-like gene (D6D) and stearoyl-CoA desaturase (SCD) mRNA levels in muscle were up-regulated (P < 0.05) 12.7- and 17.9-fold, respectively, and the D6D mRNA level in the gonad of transgenic fish was up-regulated 6.9-fold (P < 0.05) compared to that of non-transgenic fish. In contrast, D6D and SCD mRNA levels in transgenic fish were dramatically down-regulated (P < 0.05), 50.2- and 16.7-fold in brain, and 5.4- and 2.4-fold in liver, respectively, in comparison with those of non-transgenic fish. When fed a specially formulated diet, D6D and SCD mRNA levels in muscle of transgenic fish were up-regulated (P < 0.05) 41.5- and 8.9-fold, respectively, and in liver 6.0- and 3.3-fold, respectively, compared to those of non-transgenic fish. In contrast, D6D and SCD mRNA levels in the gonad of transgenic fish were down-regulated (P < 0.05) 5.5- and 12.4-fold, respectively, and D6D and SCD mRNA levels in the brain were down-regulated 14.9- and 1.4-fold (P < 0.05), respectively, compared to those of non-transgenic fish. The transgenic common carp fed the commercial diet had 1.07-fold EPA, 1.12-fold DPA, 1.07-fold DHA, and 1.07-fold higher observed total omega-3 fatty acid levels than non-transgenic common carp. Although these differences were not statistically different (P > 0.05), there were significantly (P < 0.10) higher omega-3 fatty acid levels when considering the differences for all of the individual omega-3 fatty acids. The genotype × diet interactions observed indicated that the potential of desaturase transgenesis cannot be realized without using a well-designed diet with the needed amount of substrates.

Newborns with lower levels of circulating polyunsaturated fatty acids (PUFA) are abdominally more adipose

BACKGROUND

Maternal nutrition is the main source of Poly-Unsaturated Fatty Acids (PUFA) for the fetus. PUFA may influence the accumulation of fat in early life.

OBJECTIVES & METHODS

In 33 breastfed infants born appropriate-for-gestational-age, we studied whether body composition (judged by absorptiometry at 2 wk and 4 mo) relates to PUFA levels (assessed by gas chromatography) in the maternal or fetal circulation at birth.

RESULTS

Abdominal fat at 2 wk associated negatively to umbilical-cord levels of separate PUFA (linoleic, arachidonic, eicosapentanoic and docosahexaenoic acid; all P between 0.001 and 0.015). Collectively, the assessed n-6 PUFA on one hand and the n-3 PUFA on the other hand associated negatively to the absolute amount of abdominal fat (in grams; P = 0.001 and P = 0.002, respectively) and to the relative amount of abdominal fat (fraction of total fat; P = 0.001 and P = 0.006, respectively). No other significant associations were observed.

CONCLUSION

In conclusion, newborns with lower levels of circulating PUFA were found to be abdominally more adipose. The mechanisms underpinning these associations remain to be determined.

Maternal dietary fat affects the LT muscle fatty acid composition of progeny at weaning and finishing stages in pigs

The present study was conducted to investigate whether maternal dietary fat affects the fatty acid composition of the longissimus thoracis (LT) muscle in offspring pigs at weaning and finishing stages. Fourteen sows were randomly assigned to a control or a high fat (HF) group. The HF sows received a diet containing 8% corn oil starting seven days before farrowing until weaning. The results showed that a high-fat diet significantly increased the contents of serum-lipid-related indexes in the sows. Although the triglyceride content did not change, the C18:2n-6 content was higher in the colostrum and in the LT muscle of offspring pigs at both investigated stages. The total n-6 content and the n-6/n-3 ratio generally increased. This study demonstrated that maternal dietary fat during lactation affects the fatty acid composition of the LT muscle of progeny at weaning, and can have persistent effects in later life.

Postnatal dietary fatty acid composition permanently affects the structure of hypothalamic pathways controlling energy balance in mice

BACKGROUND

We previously reported that dietary lipid quality during early life can have long-lasting effects on metabolic health and adiposity. Exposure to a postnatal diet with low dietary omega-6 (n-6) or high omega-3 (n-3) fatty acid (FA) content resulted in reduced body fat accumulation when challenged with a moderate Western-style diet (WSD) beginning in adolescence.

OBJECTIVE

We determined whether this programming effect is accompanied by changes in hypothalamic neural projections or modifications in the postnatal leptin surge, which would indicate the altered development of hypothalamic circuits that control energy balance.

DESIGN

Neonatal mice were subjected to a control diet (CTR) or experimental diet with altered relative n-6 and n-3 FA contents [ie, a diet with a relative reduction in n-6 fatty acid (LOW n-6) or a diet with a relative increase in n-3 fatty acid (HIGH n-3) compared with the CTR from postnatal day (PN) 2 to 42].

RESULTS

Compared with CTR mice, mice fed a LOW n-6 or HIGH n-3 during postnatal life showed significant reductions in the density of both orexigenic and anorexigenic neural projections to the paraventricular nucleus of the hypothalamus at PN 28. These impairments persisted into adulthood and were still apparent after the WSD challenge between PNs 42 and 98. However, the neuroanatomical changes were not associated with changes in the postnatal leptin surge.

CONCLUSION

Although the exact mechanism remains to be elucidated, our data indicate that the quality of dietary FA during postnatal life affects the development of the central regulatory circuits that control energy balance and may do so through a leptin-independent mechanism.

The role of dietary fatty acids for early human adipose tissue growth

Childhood obesity is increasing worldwide, and all previous attempts to stop this epidemic have shown little success. There is now growing evidence that the risk of childhood obesity is strongly influenced by perinatal determinants, including prepregnancy body mass index (BMI), gestational weight gain, and—at least in animal studies—dietary factors during pregnancy and lactation. This review addresses the issue of whether modulation of fat intake and its composition in this early-life period has a potential for primary prevention of childhood obesity. Of particular interest is the question of whether supplementation with n–3 long-chain PUFAs (LC-PUFAs) may exert an antiobesity effect. Retrospective analysis of human randomized controlled trials with fish-oil intervention during pregnancy and lactation gave inconsistent results concerning BMI and obesity development in offspring. A recent prospective human intervention study aimed at reducing the n–6:n–3 LC-PUFA ratio did not show an effect on adipose tissue growth in offspring up to the age of 1 y. Therefore, there is currently little evidence to support the hypothesis that dietary intervention to modify fat composition during pregnancy and lactation would be a promising strategy to prevent childhood obesity in humans, but more research is clearly needed to address the question if and how the risk of developing obesity can be modified by dietary intervention early in life.

Breast milk fatty acid profile in relation to infant growth and body composition: results from the INFAT study

BACKGROUND

There is some evidence that the n-6/n-3 long-chain polyunsaturated fatty acids (LCPUFAs) ratio in early nutrition, and thus in breast milk, could influence infant body composition.

METHODS

In an open-label randomized controlled trial (RCT), 208 healthy pregnant women were allocated to a dietary intervention (supplementation with 1,200 mg n-3 LCPUFAs per day and instructions to reduce arachidonic acid (AA) intake) from the 15th wk of gestation until 4 mo of lactation or to follow their habitual diet. Breast milk LCPUFAs at 6 wk and 4 mo postpartum were related to infant body composition assessed by skinfold thickness (SFT) measurements and ultrasonography during the first year of life.

RESULTS

Dietary intervention significantly reduced breast milk n-6/n-3 LCPUFAs ratio. In the whole sample, early breast milk docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and n-3 LCPUFAs at 6 wk postpartum were positively related to the sum of four SFT measurements at age 1. Breast milk AA and n-6 LCPUFAs at 6 wk postpartum were negatively associated with weight, BMI, and lean body mass (LBM) up to 4 mo postpartum.

CONCLUSION

Breast milk n-3 LCPUFAs appear to stimulate fat mass growth over the first year of life, whereas AA seems to be involved in the regulation of overall growth, especially in the early postpartum period.

Transgenic increase in N-3/n-6 Fatty Acid ratio reduces maternal obesity-associated inflammation and limits adverse developmental programming in mice

Maternal and pediatric obesity has risen dramatically over recent years, and is a known predictor of adverse long-term metabolic outcomes in offspring. However, which particular aspects of obese pregnancy promote such outcomes is less clear. While maternal obesity increases both maternal and placental inflammation, it is still unknown whether this is a dominant mechanism in fetal metabolic programming. In this study, we utilized the Fat-1 transgenic mouse to test whether increasing the maternal n-3/n-6 tissue fatty acid ratio could reduce the consequences of maternal obesity-associated inflammation and thereby mitigate downstream developmental programming. Eight-week-old WT or hemizygous Fat-1 C57BL/6J female mice were placed on a high-fat diet (HFD) or control diet (CD) for 8 weeks prior to mating with WT chow-fed males. Only WT offspring from Fat-1 mothers were analyzed. WT-HFD mothers demonstrated increased markers of infiltrating adipose tissue macrophages (P<0.02), and a striking increase in 12 serum pro-inflammatory cytokines (P<0.05), while Fat1-HFD mothers remained similar to WT-CD mothers, despite equal weight gain. E18.5 Fetuses from WT-HFD mothers had larger placentas (P<0.02), as well as increased placenta and fetal liver TG deposition (P<0.01 and P<0.02, respectively) and increased placental LPL TG-hydrolase activity (P<0.02), which correlated with degree of maternal insulin resistance (r = 0.59, P<0.02). The placentas and fetal livers from Fat1-HFD mothers were protected from this excess placental growth and fetal-placental lipid deposition. Importantly, maternal protection from excess inflammation corresponded with improved metabolic outcomes in adult WT offspring. While the offspring from WT-HFD mothers weaned onto CD demonstrated increased weight gain (P<0.05), body and liver fat (P<0.05 and P<0.001, respectively), and whole body insulin resistance (P<0.05), these were prevented in WT offspring from Fat1-HFD mothers. Our results suggest that reducing excess maternal inflammation may be a promising target for preventing adverse fetal metabolic outcomes in pregnancies complicated by maternal obesity.

Sex-dependent nutritional programming: fish oil intake during early pregnancy in rats reduces age-dependent insulin resistance in male, but not female, offspring

Prenatal and early postnatal nutritional status may predispose offspring to impaired glucose tolerance and changes in insulin sensitivity in adult life. The long-term consequences of changes in maternal dietary fatty acid composition were determined in rats. From day 1 until day 12 of pregnancy, rats were given isocaloric diets containing 9% nonvitamin fat based on soybean, olive, fish (FO), linseed, or palm oil. Thereafter, they were maintained on the standard diet; offspring were studied at different ages. Body weight at 4, 8, and 12 mo and lumbar adipose tissue and liver weights at 12 mo did not differ between females on the different diets, whereas in males the corresponding values were all lower in the offspring from the FO group compared with the other dietary groups. Plasma glucose concentrations (both basal and after an oral glucose load) did not change with sex or dietary group, but plasma insulin concentrations were lower in females than in males and, in males, were lowest in the FO group. Similar relations were found with both the homeostasis model assessment of insulin resistance and insulin sensitivity index. In conclusion, the intake of more n–3 fatty acids (FO diet) during early pregnancy reduced both fat accretion and age-related decline in insulin sensitivity in male offspring but not in females. It is proposed that the lower adiposity caused by the increased n–3 fatty acids during the intrauterine life was responsible of the lower insulin resistance in male offspring.

Early life nutritional programming of obesity: mother-child cohort studies

BACKGROUND

The obesity epidemic has resulted in more overweight/obese women before and during pregnancy. Their offspring tend to have higher birth weights and more body fat, and carry an increased risk of obesity later in life. These effects may partly be related to the heightened risk of gestational diabetes, occurring in at least 16% of all pregnancies irrespective of current body weight.

METHODS

An ILSI Europe workshop reviewed the key contributors leading to adverse outcomes in pregnancy and childhood, including gestational weight gain and nutrition. New research opportunities from prospective mother-child cohort studies were explored.

RESULTS

Simple measures of gestational weight gain provide insufficient detail of the underlying physiological and metabolic adaptations occurring in pregnancy, and should be complemented by measures of body composition, metabolic and endocrine responses. Recordings of maternal dietary intake and nutrient status are often limited and potential correlations with gestational weight gain have been poorly studied. Many pregnancies in overweight/obese women are uncomplicated and result in offspring of normal weight, leaving the main determinants of later adverse outcomes to be clarified.

CONCLUSIONS

The workshop provided insights of primary measurements for the characterization of sustainable nutritional intervention strategies in the mother, infant and child for preventing obesity in later life.

Maternal plasma polyunsaturated fatty acid status in late pregnancy is associated with offspring body composition in childhood

CONTEXT

Maternal diet during pregnancy has been linked to offspring adiposity, but it is unclear whether maternal polyunsaturated fatty acid (PUFA) status during pregnancy affects offspring body composition.

OBJECTIVE

We investigated the associations between maternal plasma n-3 and n-6 PUFA status at 34 wk gestation and offspring body composition.

DESIGN AND SETTING

A prospective United Kingdom population-based mother-offspring cohort, the Southampton Women's Survey (SWS), was studied.

PARTICIPANTS

A total of 12,583 nonpregnant women were recruited into the SWS, among whom 1987 delivered a baby before December 31, 2003; 293 mother-child pairs had complete measurements of maternal plasma PUFA concentrations in late pregnancy and offspring body composition at both ages 4 and 6 yr.

MAIN OUTCOMES MEASURED

We measured offspring body composition by dual-energy x-ray absorptiometry, yielding fat mass, lean mass, percentage fat mass, and percentage lean mass. Results are presented as β-coefficients for standardized variables, therefore reflecting the sd change of the outcome for every 1 sd of the predictor.

RESULTS

After adjustment for maternal factors and child factors including height and duration of breast-feeding, maternal plasma n-6 PUFA concentration positively predicted offspring fat mass at 4 yr (β = 0.14 SD/SD; P = 0.01) and 6 yr (β = 0.11 SD/SD; P = 0.04), but there was no association with offspring lean mass at either age (β = 0.005 SD/SD, P = 0.89; and β = 0.008 SD/SD, P = 0.81, respectively). Maternal plasma n-3 PUFA concentration was not associated with offspring fat mass at 4 yr (β = 0.057 SD/SD; P = 0.34) or 6 yr (β = 0.069 SD/SD; P = 0.21). Maternal plasma n-3 PUFA status was positively associated with offspring lean mass on univariate analysis (4 yr, β = 0.11, P = 0.06; 6 yr, β = 0.14; P = 0.02); however, this was confounded by a positive association with offspring height.

CONCLUSIONS

This observational study suggests that maternal n-6 PUFA status during pregnancy might influence offspring adiposity in childhood.

Perinatal manipulation of α-linolenic acid intake induces epigenetic changes in maternal and offspring livers

Previous studies indicated that the intake of α-linolenic acid (ALA) can alter the concentration of both ω-6 and ω-3 fatty acids in both mother and offspring, with consequences on postnatal brain development. This study describes the association between maternal ALA availability during gestation and lactation, and alterations in the Fads2 DNA methylation in both maternal and offspring livers, at the end of lactation period. Both Fads2 promoter and intron 1 DNA methylation were increased in the groups receiving postnatal flaxseed oil containing 50% ALA (mothers or pups), while bivariate analysis indicated a significant association of the Fads2 epigenetic status in the liver between each mother and its offspring. In addition, Fads2 expression was negatively correlated with promoter methylation at the individual level in maternal livers (P<0.05). This study also indicated that the interplay between ALA availability during gestation and lactation can differentially alter the expression of desaturases and elongases involved in ω-6 and ω-3 metabolic pathways. In summary, when considering the perinatal dietary ALA requirements in mice, both gestation and lactation periods should be considered as having distinct roles in modulating the metabolism of ω-6 and ω-3 fatty acids in maternal mouse livers.