Maternal obesity and/or high-fat diet during pregnancy predispose the offspring to metabolic disease. It is however unclear how pre-natal and post-natal exposure respectively affect the risk of hepatic steatosis and the trajectory towards non-alcoholic steatohepatitis in the offspring. We investigate hepatic lipid metabolism and how these factors are related to metabolic outcome in new born and young rats. Rat dams were exposed to a high-fat/high sucrose (HFHS) diet for 17 weeks prior to mating and during pregnancy. After birth, female offspring were killed and male offspring were cross-fostered, creating four groups; Control-born pups lactated by control (CC) or HFHS dams (CH) and HFHS-born pups lactated by control (HC) or HFHS dams (HH). At 4 weeks of age, pups were killed and metabolic markers in plasma were assayed, together with hepatic lipid composition and expression of relevant genes. Female HFHS neonates had smaller livers at birth (P < .05), a reduced hepatic lipid content (P < .05) and altered lipid composition. The post-natal environment dominated the metabolic profile in the male offspring at 4 weeks of age. Offspring exposed to a HFHS environment post-natally had increased adiposity (P < .0001), increased hepatic triacylglycrol accumulation (P < .0001), and an altered lipid profile with elevated n-6 polyunsaturated fatty acid (PUFA) levels (P < .0001) and a reduction in ceramide (P < .001) and monounsaturated fatty acid (MUFA) (P < .0001). In summary, maternal HFHS diet during gestation affects the hepatic lipid profile in neonates. The pre-natal exposure becomes less pronounced in young male offspring at 4 weeks of age, where the post-natal diet has the largest impact.
The objective of this study was to investigate the effect of increasing dietary supplementation of crushed sunflower seed (CSS) in the diet of dairy cows on the fatty acid (FA) composition of phospholipids and sphingomyelin in milk, and on mammary transcription of genes that are important for sphingomyelin de novo synthesis. Four groups of 6 cows received diets supplemented with CSS at 0% (control), or 5, 10, or 15% of dry matter for a 5-wk experimental period. Milk samples and mammary biopsies were collected at the end of the experiment. Phospholipid concentration in milk fat decreased linearly with CSS supplementation. Sphingomyelin concentration in milk fat was unaffected by CSS supplementation. Daily yield of phospholipids decreased linearly with CSS supplementation. Daily yield of sphingomyelin was not significantly affected. The CSS supplementation linearly increased the proportion of monounsaturated FA in milk phospholipids. The major isomer incorporated into phospholipids was C18:1 (n-9 cis), which showed a linear increase with CSS supplementation. The C22:0 proportion in sphingomyelin increased linearly with CSS supplementation and constituted between 15.2 to 25.4% of total FA in sphingomyelin. However, CSS supplementation linearly decreased C23:0 sphingomyelin. Mammary transcription of serine palmitoyl transferase, long chain subunit 1 and subunit 2, the rate-limiting enzymes in ceramide synthesis, showed a linear decrease with increasing CSS supplementation. In conclusion, the data showed that dietary supplementation of CSS linearly increased the proportion of unsaturated FA and monounsaturated FA in milk phospholipids with no effect on phospholipid concentration. In addition, CSS supplementation linearly decreased n-3 polyunsaturated fatty acid proportion in sphingomyelin. The results further showed that mammary transcription of important genes for sphingomyelin de novo synthesis is regulated by lipid supplementation.
The aim of this experiment was to investigate the effect of dietary supplementation of crushed high oleic sunflower seeds (HOS) and rumen-protected choline (RPC) on the fatty acid (FA) profile of phospholipids and sphingomyelin and mammary transcription of genes that are important for milk fat synthesis and de novo synthesis of sphingolipids. Twenty-four cows were divided into four groups that either received an unsupplemented diet (Control), the Control diet supplemented with 50 g RPC per day, a diet supplemented with HOS at 10% of dry matter, or RPC and HOS in combination (RPC + HOS). RPC supplementation had no effect on the FA composition of milk or sphingomyelin. Cows receiving RPC and RPC + HOS had increased incorporation of C22:5 (n-3) into phospholipids. Milk FA proportion of C18:0 and C18:1 isomers was increased in cows receiving HOS (HOS and RPC + HOS). Sphingomyelin proportion of C22:0 was increased in cows receiving HOS and RPC + HOS, at the expense of C23:0. HOS supplementation further increased the proportion of unsaturated fatty acids (UFA) in milk phospholipids. HOS supplementation increased mammary transcription of UDP-glucose ceramide glycosyltransferase (UGCG), sterol response element-binding protein cleavage-activating protein (SCAP) and peroxisome proliferation-activated receptor Gamma subunit C 1b (PPARGC1b), and reduced transcription of insulin induced gene 1 (INSIG1) and fatty acid-binding protein 3 (FABP3). Dietary supplementation of RPC increased mammary transcription of fatty acid desaturase 1 (FADS1) and longevity assurance gene 2 (LASS2), and reduced transcription of sphingomyelin synthase (SGMS). The results show that the FA profile of milk phospholipids is sensitive to dietary lipid supplementation and, to a minor degree, RPC supplementation. Furthermore, transcription of genes that are important for milk fat synthesis and sphingolipids synthesis is affected by dietary supplementation of RPC and HOS.
In obesity and dyslipidemia, hydrolysis of triacylglycerol (TAG) into non-esterified fatty acids (NEFAs) may contribute to insulin resistance, and production of oxygenated, bioactive polyunsaturated fatty acids may increase oxidative stress. Here we show that after six weeks of high-fat feeding of obese prone rats (Crl:OP(CD), vitamin C was increased both in liver (P < 0.01) and plasma (P < 0.001), while both TAG (P < 0.01) and NEFA (P < 0.001) were lower than in low-fat fed control rats. Hepatic vitamin C biosynthesis was similar between groups, indicating that a new steady state level was established with a higher vitamin C level adequate for supplying the systemic needs. Glucose and insulin sensitivity were unaffected at this stage. Eventually, the mobilization of vitamin C may be seen as a mechanism to protect the host against insulin resistance.
Human milk fat contains high concentrations of medium-chained fatty acids (MCFA) and triacylglycerols emulsified by a sphingomyelin-rich phospholipid membrane (milk phospholipids, MPL). Infant formula comprises mainly long-chained fatty acids (LCFA) emulsified with dairy proteins and soy lecithin (SL) lacking sphingomyelin. Sphingomyelin content and saturation level of phospholipids affect the gut lipase activity, which alters the concentrations of lipid hydrolysis products in ileum and colon, and hereby putatively affects the competitive advantage of specific gut bacteria. Thus, differences in phospholipid and FA composition may modulate the establishment of the gut microbiota. We investigated effects of fatty acid (FA) composition and emulsification (MPL vs SL) ingested during establishment of human gut microbiota in germ-free mice, and found that cecal microbiotas from mice given MCFA-rich emulsions were characterized by high relative abundances of Bacteroidaceae and Desulfovibrionaceae, while LCFA-rich emulsions caused higher abundances of Enterobacteriaceae, Erysipelotrichaceae, Coriobacteriaceae and Enterococcaceae. Consumption of SL-emulsified lipids skewed the community towards more Enterococcaceae and Enterobacteriaceae, while MPL increased Bacteroidaceae, Desulfovibrionaceae, Rikkenellaceae and Porphyromonadaceae. Intake of SL increased cecal concentrations of iso-valeric and iso-butyric acids. This suggests that fat-type and emulsifiers applied in infant formula may have distinct effects on the establishment of the gut microbiota in formula-fed infants.
Dietary gluten causes severe disorders like celiac disease in gluten-intolerant humans. However, currently understanding of its impact in tolerant individuals is limited. Our objective was to test whether gliadin, one of the detrimental parts of gluten, would impact the metabolic effects of an obesogenic diet. Mice were fed either a defined high-fat diet (HFD) containing 4% gliadin (n = 20), or a gliadin-free, isocaloric HFD (n = 20) for 23 weeks. Combined analysis of several parameters including insulin resistance, histology of liver and adipose tissue, intestinal microbiota in three gut compartments, gut barrier function, gene expression, urinary metabolites and immune profiles in intestinal, lymphoid, liver and adipose tissues was performed. Mice fed the gliadin-containing HFD displayed higher glycated hemoglobin and higher insulin resistance as evaluated by the homeostasis model assessment, more hepatic lipid accumulation and smaller adipocytes than mice fed the gliadin-free HFD. This was accompanied by alterations in the composition and activity of the gut microbiota, gut barrier function, urine metabolome, and immune phenotypes within liver and adipose tissue. Our results reveal that gliadin disturbs the intestinal environment and affects metabolic homeostasis in obese mice, suggesting a detrimental effect of gluten intake in gluten-tolerant subjects consuming a high-fat diet.
ScopeOmega‐6 (n‐6) PUFA‐rich diets are generally considered obesogenic in rodents. Here, we examined how long‐term intake of a high‐fat/high‐sucrose (HF/HS) diet based on safflower oil affected metabolism, inflammation, and gut microbiota composition.Methods and resultsWe fed male C57BL/6J mice a HF/HS diet based on safflower oil—rich in n‐6 PUFAs—or a low‐fat/low‐sucrose diet for 40 wk. Compared to the low‐fat/low‐sucrose diet, intake of the safflower‐based HF/HS diet only led to moderate weight gain, while glucose intolerance developed at week 5 prior to signs of inflammation, but concurrent with increased levels of linoleic acid and arachidonic acid in hepatic phospholipids. Intake of the HF/HS diet resulted in early changes in the gut microbiota, including an increased abundance of Blautia, while late changes coincided with altered inflammatory profiles and increased fasting plasma insulin. Analysis of immune cells in visceral fat and liver revealed no differences between diets before week 40, where the number of immune cells decreased in the liver of HF/HS‐fed mice.ConclusionWe suggest that a diet‐dependent increase in the n‐6 to omega‐3 (n‐3) PUFA ratio in hepatic phospholipids together with gut microbiota changes contributed to early development of glucose intolerance without signs of inflammation.
Background and PurposeObesity and associated co‐morbidities, such as type 2 diabetes and non‐alcoholic fatty liver disease, are major health challenges. Hence, there is an important need to develop weight loss therapies with the ability to reduce the co‐morbidities.Experimental ApproachThe effect of the dual amylin and calcitonin receptor agonist (DACRA), KBP‐089, on body weight, glucose homeostasis and fatty acid accumulation in liver and muscle tissue and on food preference was investigated. Furthermore, we elucidated weight‐independent effects of KBP‐089 using a weight‐matched group.Key ResultsRats fed a high‐fat diet were treated, s.c., with KBP‐089 0.625, 1.25, 2.5 μg·kg−1 or vehicle. KB‐089 induced in a dose‐dependent and sustained weight loss (~17% by 2.5 μg·kg−1). Moreover, KBP‐089 reduced fat depot size and reduced lipid accumulation in muscle and liver. In Zucker Diabetic Fatty rats, KBP‐089 improved glucose homeostasis through improved insulin action. To obtain a weight‐matched group, significantly less food was offered (9% less than in the KBP‐089 group). Weight matching led to improved glucose homeostasis by reducing plasma insulin; however, these effect were inferior compared to those of KBP‐089. In the food preference test, rats fed a normal diet obtained 74% of their calories from chocolate. KBP‐089 reduced total caloric intake and induced a relative increase in chow consumption while drastically reducing chocolate consumption compared with vehicle.Conclusions and ImplicationsThe novel DACRA, KBP‐089, induces a sustained weight loss, leading to improved metabolic parameters including food preference, and these are beyond those observed simply by diet‐induced weight loss.
Learning and memory have been shown to be influenced by combination of dietary supplements and exercise in animal models, but there is little available evidence from human subjects. The aim of this pilot study was to investigate the effect of combining a motor- and cognitive exercise program with dietary supplementation consisting of 500 mg docosahexaenoic acid (DHA), 10 μg vitamin D3 and 1000 mg uridine (DDU-supplement) in 16 prepubescent children (age 8–11 years).
Objectives: To investigate the pathophysiological pathways leading to symptoms elicitation in multiple chemical sensitivity (MCS) by comparing gene expression in MCS participants and healthy controls before and after a chemical exposure optimised to cause symptoms among MCS participants.The first hypothesis was that unexposed and symptom-free MCS participants have similar gene expression patterns to controls and a second hypothesis that MCS participants can be separated from controls based on differential gene expression upon a controlled n-butanol exposure.Design: Participants were exposed to 3.7 ppm n-butanol while seated in a windowed exposure chamber for 60 min. A total of 26 genes involved in biochemical pathways found in the literature have been proposed to play a role in the pathogenesis of MCS and other functional somatic syndromes were selected. Expression levels were compared between MCS and controls before, within 15 min after being exposed to and 4 hours after the exposure.Settings: Participants suffering from MCS and healthy controls were recruited through advertisement at public places and in a local newspaper.Participants: 36 participants who considered themselves sensitive were prescreened for eligibility. 18 sensitive persons fulfilling the criteria for MCS were enrolled together with 18 healthy controls.Outcome measures: 17 genes showed sufficient transcriptional level for analysis. Group comparisons were conducted for each gene at the 3 times points and for the computed area under the curve (AUC) expression levels.Results: MCS participants and controls displayed similar gene expression levels both at baseline and after the exposure and the computed AUC values were likewise comparable between the 2 groups. The intragroup variation in expression levels among MCS participants was noticeably greater than the controls.Conclusions: MCS participants and controls have similar gene expression levels at baseline and it was not possible to separate MCS participants from controls based on gene expression measured after the exposure.
Amylin and GLP-1 agonism induce a well-known anorexic effect at dose initiation, which is managed by dose escalation. In this study we investigated how to optimize tolerability while maintaining efficacy of a novel, highly potent dual amylin and calcitonin receptor agonist (DACRA), KBP-089. Furthermore, we tested the GLP-1 add-on potential of KBP-089 in high-fat diet (HFD)-fed rats. KBP-089 potently activated both the amylin and calcitonin receptors in vitro and demonstrated a prolonged receptor activation as well as a potent reduction of acute food intake. HFD rats dosed every day or every second day obtained equal weight loss at study end, albeit with an uneven reduction in both food intake and body weight in rats dosed every second day. In a 4-fold dose escalation, KBP-089 induced a transient reduction in food intake at every escalation step, with reducing magnitude over time, and the following treatment with 2.5, 10, and 40 µg/kg resulted in an ~15% vehicle-corrected weight loss, a corresponding reduction in adipose tissue (AT), and, in all treatment groups, improved oral glucose tolerance ( P < 0.01). Twofold and linear escalations suppressed body weight evenly with no significant reduction in food intake at either escalation step. KBP-089 (1.25 µg/kg) and liraglutide (50 µg/kg) reduced 24-h food intake by 29% and 37% compared with vehicle, respectively; however, when they were combined, 24-h food intake was reduced by 87%. Chronically, KBP-089 (1.25 µg/kg) and liraglutide (50 µg/kg) lowered body weight 8% and 2% in HFD rats, respectively, whereas the combination resulted in a 12% body weight reduction. Moreover, the combination improved glucose tolerance ( P < 0.05). In conclusion, DACRAs act complementarily with GLP-1 on food intake and body weight. Furthermore, on escalation, KBP-089 was well tolerated and induced and sustained a significant weight loss and a reduction in AT in lean and HFD rats, underscoring the potential of KBP-089 as an anti-obesity agent.
AbstractDHA from diet or endogenous synthesis has been proposed to affect infant development, however, results are inconclusive. In this study, we aim to verify previously observed fatty acid desaturase gene cluster (FADS) SNP-specific associations with erythrocyte DHA status in 9-month-old children and sex-specific association with developmental outcomes. The study was performed in 166 children (55 % boys) of obese mothers. Erythrocyte fatty acid composition was analysed in blood-samples obtained at 9 months of age, and developmental outcomes assessed by the Ages and Stages Questionnaire at 3 years. Erythrocyte DHA level ranged from 4·4 to 9·9 % of fatty acids, but did not show any association withFADSSNP or other potential determinants. Regression analysis showed associations between erythrocyte DHA and scores for personal–social skills (β1·8 (95 % CI 0·3, 3·3),P=0·019) and problem solving (β3·4 (95 % CI 1·2, 5·6),P=0·003). A tendency was observed for an association in opposite direction between minor alleles (G-variant) of rs1535 and rs174575 and personal–social skills (P=0·062 and 0·068, respectively), which became significant when the SNP were combined based on their previously observed effect on erythrocyte DHA at 9 months of age (β2·6 (95 % CI 0·01, 5·1),P=0·011). Sex–SNP interaction was indicated for rs174575 genotype on fine motor scores (P=0·016), due to higher scores among minor allele carrying girls (P=0·043), whereas no effect was seen among boys. In conclusion, DHA-increasingFADSSNP and erythrocyte DHA status were consistently associated with improved personal–social skills in this small cohort of children of obese mothers irrespective of sex, but the sample was too small to verify potential sex-specific effects.
Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) cohort
Milk fat is the most important energy source for the newborn infant beside its important role as energy source, milk fat also contain a range of bioactive lipids, that potentially can modulate the immune response and metabolic regulation in the child. In this chapter we review the literature on bioactive dairy fatty acids: conjugated linoleic acid, branched chained and odd chained fatty acids, as well as bioactive complex lipids such as sphingomyelin and gangliosides.
In this study, KBP‐042, a dual amylin‐ and calcitonin‐receptor agonist, was investigated as a treatment of obesity and insulin resistance in five different doses (0.625 µg/kg–10 µg/kg) compared with saline‐treated and pair‐fed controls.
Several studies have investigated the effects of fish oil (FO) on infant growth, but little is known about the effects of FO and sex on insulin-like growth factor-1 (IGF-1), the main regulator of growth in childhood. We explored whether FO v. sunflower oil (SO) supplementation from 9 to 18 months of age affected IGF-1 and its binding protein-3 (IGFBP-3) and whether the potential effects were sex specific. Danish infants (n 115) were randomly allocated to 5 ml/d FO (1·2 g/d n-3 long-chain PUFA (n-3 LCPUFA)) or SO. We measured growth, IGF-1, IGFBP-3 and erythrocyte EPA, a biomarker of n-3 LCPUFA intake and status, at 9 and 18 months. Erythrocyte EPA increased strongly with FO compared with SO (P<0·001). There were no effects of FO compared with SO on IGF-1 in the total population, but a sex × group interaction (P=0·02). Baseline-adjusted IGF-1 at 18 months was 11·1 µg/l (95% CI 0·4, 21·8; P=0·04) higher after FO compared with SO supplementation among boys only. The sex × group interaction was borderline significant in the model of IGFBP-3 (P=0·09), with lower IGFBP-3 with FO compared with SO among girls only (P=0·03). The results were supported by sex-specific dose-response associations between changes in erythrocyte EPA and changes in IGF-1 and IGFBP-3 (both P<0·03). Moreover, IGF-1 was sex specifically associated with BMI and length. In conclusion, FO compared with SO resulted in higher IGF-1 among boys and lower IGFBP-3 among girls. The potential long-term implications for growth and body composition should be investigated further.
We hypothesized that an increased, incomplete fatty acid beta-oxidation in mitochondria could be part of the metabolic events leading to insulin resistance and thereby an increased type 2 diabetes risk in low birth weight (LBW) compared with normal birth weight (NBW) individuals. Therefore, we measured fasting plasma levels of 45 acylcarnitine species in 18 LBW and 25 NBW men after an isocaloric control diet and a 5-day high-fat, high-calorie diet. We demonstrated that LBW men had higher C2 and C4-OH levels after the control diet compared with NBW men, indicating an increased fatty acid beta-oxidation relative to the tricarboxylic acid cycle flux. Also, they had higher C6-DC, C10-OH/C8-DC, and total hydroxyl-/dicarboxyl-acylcarnitine levels, which may suggest an increased fatty acid omega-oxidation in the liver. Furthermore, LBW and NBW men decreased several acylcarnitine levels in response to overfeeding, which is likely a result of an upregulation of fatty acid oxidation due to the dietary challenge. Moreover, C10-OH/C8-DC and total hydroxyl-/dicarboxyl-acylcarnitine levels tended to be negatively associated with the serum insulin level, and the total hydroxyl-/dicarboxyl-acylcarnitine level additionally tended to be negatively associated with the hepatic insulin resistance index. This indicates that an increased fatty acid omega-oxidation could be a compensatory mechanism to prevent an accumulation of lipid species that impair insulin signaling.
Insulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin-resistant individuals is characterized by increased levels of branched-chain amino acids (BCAAs), which correlate with a gut microbiome that has an enriched biosynthetic potential for BCAAs and is deprived of genes encoding bacterial inward transporters for these amino acids. Prevotella copri and Bacteroides vulgatus are identified as the main species driving the association between biosynthesis of BCAAs and insulin resistance, and in mice we demonstrate that P. copri can induce insulin resistance, aggravate glucose intolerance and augment circulating levels of BCAAs. Our findings suggest that microbial targets may have the potential to diminish insulin resistance and reduce the incidence of common metabolic and cardiovascular disorders.
Background & aims: Previous studies have shown that fetal life malnutrition affects preferences for fat deposition in the body thereby predisposing for visceral adipocity and associated disorders in glucose-insulin regulation. In this study, we aimed to test the hypotheses that late-gestation undernutrition 1) has long-term differential impacts on development, expandability and metabolic features in subcutaneous as compared to perirenal and mesenteric adipose tissues, which 2) will predispose for visceral obesity upon exposure to an obesogenic diet in early postnatal life. Methods: Twin-bearing last trimester ewes received diets supplying 100% (NORM) or 50% (LOW) of protein and energy requirements. Lambs received moderate, low-fat (CONV) or high-carbohydrate-high-fat (HCHF) diets from 3-days until 6-months of age (just after puberty), and then half the lambs (including all males) were sacrificed. Remaining animals (exclusively females) received a low-fat, grass-based diet until sacrificed at 2-years of age (adulthood). In subcutaneous, perirenal and mesenteric fat, energy metabolism related gene expressions and fatty acid composition were determined. Histological evaluations were performed of subcutaneous and perirenal fat. The late-gestation undernutrition reduced whole-body insulin sensitivity and increased the risk of obesity-induced mesenteric adiposity in the sheep used in the experiment. Results: A deviating morphology of subcutaneous adipose tissue with greater occurrence of very small adipocytes (<40 μm in diameter) and collagen infiltration was observed in the non-obese LOW/CONV lambs, and after dietary correction (and associated body fat loss) it became apparent in all adult LOW sheep. LOW lambs deposited more fat in visceral compared to subcutaneous fat when exposed to the obesogenic HCHF diet. Prenatal undernutrition had differential impacts in subcutaneous versus perirenal fat on expressions of glucose-insulin signaling and lipid metabolism genes and on fatty acid composition, but these prenatal impacts were not sustained into adulthood, except to a limited extent in perirenal fat, where C14:0 was decreased in LOW sheep. Conclusions: The present study showed that greater preponderance of very small adipocytes, increased collagen infiltration and reduced subcutaneous lipid accumulation ability, as well as altered perirenal fat preferences for accumulation of C14:0 can have a fetal origin. Disturbance of normal (subcutaneous) adipose tissue development may play a key role in linking fetal malnutrition to disease risk later in life.