Perinatal maternal high-fat diet promotes alterations in hepatic lipid metabolism and resistance to the hypolipidemic effect of fish oil in adolescent rat offspring

Loss of NAT10 alleviates maternal high-fat diet-induced hepatic steatosis in male offspring of mice

OBJECTIVE

Metabolic dysfunction-associated steatotic liver disease (MASLD) is becoming an escalating health problem in pediatric populations. This study aimed to investigate the role of N-acetyltransferase 10 (NAT10) in maternal high-fat diet (HFD)-induced MASLD in offspring at early life.

METHODS

We generated male hepatocyte-specific NAT10 knockout (Nat10HKO) mice and mated them with female Nat10fl/fl mice under chow or HFD feeding. Body weight, liver histopathology, and expression of lipid metabolism-associated genes (Srebp1c, Fasn, Pparα, Cd36, Fatp2, Mttp, and Apob) were assessed in male offspring at weaning. Lipid uptake assays were performed both in vivo and in vitro. The mRNA stability assessment and RNA immunoprecipitation were performed to determine NAT10-regulated target genes.

RESULTS

NAT10 deletion in hepatocytes of male offspring alleviated perinatal lipid accumulation induced by maternal HFD, decreasing expression levels of Srebp1c, Fasn, Cd36, Fatp2, Mttp, and Apob while enhancing Pparα expression. Furthermore, Nat10HKO male mice exhibited reduced lipid uptake. In vitro, NAT10 promoted lipid uptake by enhancing the mRNA stability of CD36 and FATP2. RNA immunoprecipitation assays exhibited direct interactions between NAT10 and CD36/FATP2 mRNA.

CONCLUSIONS

NAT10 deletion in offspring hepatocytes ameliorates maternal HFD-induced hepatic steatosis through decreasing mRNA stability of CD36 and FATP2, highlighting NAT10 as a potential therapeutic target for pediatric MASLD.

Neonatal nicotine exposure affects adult rat hepatic pathways involved in endoplasmic reticulum stress and macroautophagy in a sex-dependent manner

Nonalcoholic fatty liver disease (NAFLD) involves changes in hepatic pathways, as lipogenesis, oxidative stress, endoplasmic reticulum (ER) stress, and macroautophagy. Maternal nicotine exposure exclusively during lactation leads to fatty liver (steatosis) only in the adult male offspring, not in females. Therefore, our hypothesis is that neonatal exposure to nicotine sex-dependently affects the signaling pathways involved in hepatic homeostasis of the offspring, explaining the hepatic lipid accumulation phenotype only in males. For this, between postnatal days 2 and 16, Wistar rat dams were implanted with osmotic minipumps, which released nicotine (NIC; 6 mg/Kg/day) or vehicle. The livers of offspring were evaluated at postnatal day 180. Only the male offspring that had been exposed to nicotine neonatally showed increased protein expression of markers of unfolded protein response (UPR), highlighting the presence of ER stress, as well as disruption of the activation of the macroautophagy repair pathway. These animals also had increased expression of diacylglycerol O-acyltransferase 1 and 4-hydroxynonenal, suggesting increased triglyceride esterification and oxidative stress. These parameters were not altered in the female offspring that had been neonatally exposed to nicotine, however they exhibited increased phospho adenosine monophosphate-activated protein kinase pAMPK expression, possibly as a protective mechanism. Thus, the disturbance in the hepatic homeostasis by UPR, macroautophagy, and oxidative stress modifications seem to be the molecular mechanisms underlying the liver steatosis in the adult male offspring of the nicotine-programming model. This highlights the importance of maternal smoking cessation during breastfeeding to decrease the risk of NAFLD development, especially in males.

Puberty as a DOHaD programming window: high-fat diet induces long-term hepatic dysfunction in male rats

The aim of this study was to evaluate whether high-fat (HF) diet intake during puberty can program obesity as well as generate glucose imbalance and hepatic metabolic dysfunctions in adult life. Male Wistar rats were randomly assigned into two groups: rats fed standard chow (NF) and rats fed a HF from postnatal 30-day-old (PND30) until PND60. Then, both groups were fed a standard chow from PND60 until PND120. Euthanasia and samples collections occurred at PND120. HF animals were overweight (+11%) and had increased adiposity, hyperphagia (+12%), hyperglycaemia (+13%), hyperinsulinemia (+69%), and hypertriglyceridemia (+34%). Plasma glucose levels during intravenous glucose tolerance test (ivGTT) and intraperitoneal insulin tolerance test (ipITT) were also higher in the HF group, whereas Kitt was significantly lower (-34%), suggesting reduced insulin sensitivity. In the same sense, HF animals present pancreatic islets hypertrophy and high β-cell mass. HF animals also had a significant increase in blood glucose levels during pyruvate tolerance test, indicating increased gluconeogenesis. Hepatic morphology analyses showed an increase in lipid inclusion in the HF group. Moreover, PEPCK and FAS protein expression were higher in the livers of the HF animals (+79% and + 37%, respectively). In conclusion, HF during puberty causes obese phenotype leading to glucose dyshomeostasis and nonalcoholic fatty liver disease, which can be related to the overexpression of proteins PEPCK and FAS.

Effect of Gestational Fish Oil Supplementation on Liver Metabolism and Mitochondria of Male and Female Rat Offspring Programmed by Maternal High-Fat Diet

SCOPE

Perinatal maternal moderately high-fat diet (mHFD) is associated with obesity and fatty liver disease in offspring, and maternal fish oil (FO: n-3 PUFA source) supplementation may attenuate these disorders. This study evaluates the effects of FO given to pregnant rats fed a mHFD on the offspring's liver at weaning.

METHODS AND RESULTS

Female Wistar rats receive an isoenergetic, control (CT: 10.9% from fat) or high-fat (HF: 28.7% from fat) diet before mating, and throughout pregnancy and lactation. FO supplementation (HFFO: 2.9% of FO in the HF diet) is given to one subgroup of HF dams during pregnancy. At weaning, male and female mHFD offspring display higher body mass, adiposity, and hepatic cellular damage, steatosis, and inflammation, accompanied by increased damaged mitochondria. FO does not protect pups from systemic metabolic alterations and partially mitigates hepatic histological damage induced by mHFD only in females. However, FO reduces mRNA expression of lipogenic genes, and mitochondrial damage, and modified mitochondrial morphology suggestive of early adaptations via mitochondrial dynamics.

CONCLUSIONS

Gestational FO supplementation has limited beneficial effects on the damage caused by perinatal mHFD consumption in offspring's liver at weaning. However, FO imprinting effect on lipid metabolism and mitochondria may have beneficial long-term outcomes.

Maternal high-fat diet decreases milk endocannabinoids with sex-specific changes in the cannabinoid and dopamine signaling and food preference in rat offspring

INTRODUCTION

Maternal high-fat (HF) diet during gestation and lactation programs obesity in rat offspring associated with sex-dependent and tissue-specific changes of the endocannabinoid system (ECS). The ECS activation induces food intake and preference for fat as well as lipogenesis. We hypothesized that maternal HF diet would increase the lipid endocannabinoid levels in breast milk programming cannabinoid and dopamine signaling and food preference in rat offspring.

METHODS

Female Wistar rats were assigned into two experimental groups: control group (C), which received a standard diet (10% fat), or HF group, which received a high-fat diet (29% fat) for 8 weeks before mating and during gestation and lactation. Milk samples were collected to measure endocannabinoids and fatty acids by mass spectrometry. Cannabinoid and dopamine signaling were evaluated in the nucleus accumbens (NAc) of male and female weanling offspring. C and HF offspring received C diet after weaning and food preference was assessed in adolescence.

RESULTS

Maternal HF diet reduced the milk content of anandamide (AEA) (p<0.05) and 2-arachidonoylglycerol (2-AG) (p<0.05). In parallel, maternal HF diet increased adiposity in male (p<0.05) and female offspring (p<0.05) at weaning. Maternal HF diet increased cannabinoid and dopamine signaling in the NAc only in male offspring (p<0.05), which was associated with higher preference for fat in adolescence (p<0.05).

CONCLUSION

Contrary to our hypothesis, maternal HF diet reduced AEA and 2-AG in breast milk. We speculate that decreased endocannabinoid exposure during lactation may induce sex-dependent adaptive changes of the cannabinoid-dopamine crosstalk signaling in the developing NAc, contributing to alterations in neurodevelopment and programming of preference for fat in adolescent male offspring.

Perinatal exposure to isocaloric diet with moderate-fat promotes pancreatic islets insulin hypersecretion and susceptibility to islets exhaustion in response to fructose intake in adult male rat offspring

AIMS

Perinatal maternal hypercaloric diets increase the susceptibility to metabolic disorders in the offspring. We hypothesized that maternal intake of an isocaloric moderate-fat diet (mMFD) would disturb the glucose homeostasis and favor the β-cell failure in response to fructose overload in adult male offspring.

METHODS

Female Wistar rats received an isocaloric diet (3.9 kcal/g) containing 29 % (mMFD) or 9 % as fat (mSTD) prior mating and throughout gestation and lactation. After weaning, male offspring received standard chow and fructose-drinking water (15 %) between 120 and 150 days old.

KEY FINDINGS

mMFD offspring had higher body weight, visceral adiposity and, fasting glycemia, with normal insulinemia. Fructose increased glycemia at 15 min from oral glucose administration, but only mMFD had returned to basal glucose levels at 120 min. Fructose increased HOMA-IR index regardless diet, but only mMFD exhibited hyperinsulinemia and a higher HOMA-β index. mMFD pancreatic islets showed increased area and insulin immunostaining density, suggesting β-cell hypertrophy. Fructose induced the expected compensatory hypertrophy in mSTD islets, while the opposite occurred in mMFD islets, associated with reduced insulin immunostaining, suggesting lower insulin storage. Pancreatic islets isolated from mMFD offspring exhibited higher glucose-stimulated insulin release at physiological concentrations. However, at higher glucose concentrations, the islets from fructose-treated mMFD reduced dramatically their insulin release, suggesting exhaustion.

SIGNIFICANCE

Isocaloric mMFD induced adaptive mechanism in the offspring allowing insulin hypersecretion, but under metabolic challenge with fructose, β-cell compensation shifts to exhaustion, favoring dysfunction. Therefore, a maternal MFD may contribute to developing diabetes under fructose overload in the adult offspring.

Maternal high-fat diet alters thermogenic markers but not muscle or brown adipose cannabinoid receptors in adult rats

AIMS

The endocannabinoid system (ECS) increases food intake, appetite for fat and lipogenesis, while decreases energy expenditure (thermogenesis), contributing to metabolic dysfunctions. We demonstrated that maternal high-fat diet (HFD) alters cannabinoid signaling in brown adipose tissue (BAT) of neonate and weanling male rat offspring, which have increased adiposity but also higher energy expenditure in adulthood. In this study, the main objective was to investigate the ECS expression in thermogenic tissues as BAT and skeletal muscle of adult rats programmed by maternal HFD. We hypothesized that maternal HFD would modulate ECS and energy metabolism markers in BAT and skeletal muscle of adult male offspring.

MATERIALS AND METHODS

Female rats received standard diet (9.4 % of calories as fat) or isocaloric HFD (28.9 % of calories as fat) for 8 weeks premating and throughout gestation and lactation. Male offspring were weaned on standard diet and euthanatized in adulthood.

KEY FINDINGS

Maternal HFD increased body weight, adiposity, glycemia, leptinemia while decreased testosterone levels in adult offspring. Maternal HFD did not change cannabinoid receptors in BAT or skeletal muscle as hypothesized but increased the content of uncoupling protein and tyrosine hydroxylase (thermogenic markers) in parallel to changes in mitochondrial morphology in skeletal muscle of adult offspring.

SIGNIFICANCE

In metabolic programming models, the ECS modulation in the BAT and skeletal muscle may be more important early in life to adapt energy metabolism during maternal dietary insult, and other mechanisms are possibly involved in muscle metabolism long-term regulation.

Maternal high-fat diet aggravates fructose-induced mitochondrial damage in skeletal muscles and causes differentiated adaptive responses on lipid metabolism in adult male offspring

Maternal high-fat diet (HFD) is associated with metabolic disturbances in the offspring. Fructose is a highly consumed lipogenic sugar; however, it is unknown whether skeletal muscle of maternal HFD offspring respond differentially to a fructose overload. Female Wistar rats received standard diet (STD: 9% fat) or isocaloric high-fat diet (HFD: 29% fat) during 8 weeks before mating until weaning. After weaning, male offspring received STD and, from 120 to 150 days-old, they drank water or 15% fructose in water (STD-F and HFD-F). At 150th day, we collected the oxidative soleus and glycolytic extensor digitorum longus (EDL) muscles. Fructose-treated groups exhibited hypertriglyceridemia, regardless of maternal diet. Soleus of maternal HFD offspring showed increased triglycerides and monounsaturated fatty acid content, independent of fructose, with increased fatty acid transporters and lipogenesis markers. The EDL exhibited unaltered triglycerides content, with an apparent equilibrium between lipogenesis and lipid oxidation markers in HFD, and higher lipid uptake (fatty acid-binding protein 4) accompanied by enhanced monounsaturated fatty acid in fructose-treated groups. Mitochondrial complexes proteins and Tfam mRNA were increased in the soleus of HFD, while uncoupling protein 3 was decreased markedly in HFD-F. In EDL, maternal HFD increased ATP synthase, while fructose decreased Tfam predominantly in STD offspring. Maternal HFD and fructose induced mitochondria ultrastructural damage, intensified in HFD-F in both muscles. Thus, alterations in molecular markers of lipid metabolism and mitochondrial function in response to fructose are modified by an isocaloric and moderate maternal HFD and are fiber-type specific, representing adaptation/maladaptation mechanisms associated with higher skeletal muscle fructose-induced mitochondria injury in adult offspring.

Maternal Isocaloric High-Fat Diet Induces Liver Mitochondria Maladaptations and Homeostatic Disturbances Intensifying Mitochondria Damage in Response to Fructose Intake in Adult Male Rat Offspring

SCOPE

Perinatal maternal obesity and excessive fructose consumption have been associated with liver metabolic diseases. We investigated whether moderate maternal high-fat diet affects the liver mitochondria responses to fructose intake in adult offspring.

METHODS AND RESULTS

Wistar female rats received a standard diet (mSTD) or high-fat diet (mHFD) (9% and 28.6% fat, respectively), before mating until the end of lactation. Male offspring were fed standard diet from weaning to adulthood and received water or fructose-drinking water (15%) from 120 to 150 days old. Fructose induced liver mitochondrial ultrastructural alterations with higher intensity in mHFD offspring, accompanied by reduced autophagy markers. Isolated mitochondria respirometry showed unaltered ATP-coupled oxygen consumption with increased Atp5f1b mRNA only in mHFD offspring. Fructose increased basal respiration and encoding complex I-III mRNA, only in mSTD offspring. Uncoupled respiration was lower in mHFD mitochondria that were unable to exhibit fructose-induced increase Ucp2 mRNA. Fructose decreased antioxidative defense markers, increased unfolded protein response and insulin resistance only in mHFD offspring without fructose-induced hepatic lipid accumulation.

CONCLUSION

Mitochondrial dysfunction and homeostatic disturbances in response to fructose are early events evidencing the higher risk of fructose damage in the liver of adult offspring from dams fed an isocaloric moderate high-fat diet. This article is protected by copyright. All rights reserved.

Differentiated Hepatic Response to Fructose Intake during Adolescence Reveals the Increased Susceptibility to Non-Alcoholic Fatty Liver Disease of Maternal High-Fat Diet Male Rat Offspring

SCOPE

Non-alcoholic fatty liver disease (NAFLD) among adolescents has been related to fructose intake. Additionally, maternal high-fat diet (mHFD) increases the offspring susceptibility to NAFLD at adulthood. Here, it is hypothesized that mHFD may exacerbate the fructose impact in adolescent male rat offspring, by changing the response of contributing mechanisms to liver injury.

METHODS AND RESULTS

Female Wistar rats receive standard (mSTD: 9% fat) or high-fat diet (mHFD: 29% fat) prior mating throughout pregnancy and lactation. After weaning, offspring receive standard chow and, from the 25th to 45th day, receive water or fructose-drinking water (15%). At 46 days old, fructose groups show increased adiposity, increased serum and hepatic triglycerides, regardless of maternal diet. Fructose aggravates the hepatic imbalance of redox state already exhibited by mHFD offspring. The hepatic activation of cellular repair pathways by fructose, such as unfolded protein response and macroautophagy, is disrupted only in mHFD offspring. Fructose does not change the liver morphology of mSTD offspring. However, it intensifies the liver injury already present in mHFD offspring.

CONCLUSION

Fructose intake during adolescence accelerates the emergence of NAFLD observed previously at the adult life of mHFD offspring, and reveals a differentiated hepatic response to metabolic insult, depending on the maternal diet.

Maternal conjugated linoleic acid alters hepatic lipid metabolism via the AMPK signaling pathway in chick embryos

The effects of maternal conjugated linoleic acid (CLA) on embryonic development and hepatic lipid metabolism were investigated in chick embryos. A total of 180 Arbor Acres female broiler breeders (36 wk old) were randomly divided into the following 3 dietary treatment groups: a basic diet (control), a basic diet containing 0.5% CLA (CLA1), and a basic diet containing 1.0% CLA (CLA2). The females were fed for 8 wk, and the eggs from each group were collected and hatched during the last 2 wk. The results showed that the addition of dietary CLA increased the broken egg rate and reduced the fertilization rate and the egg hatchability (P < 0.05). CLA enrichment decreased the polyunsaturated and monounsaturated fatty acids and increased the saturated fatty acids in the yolk sac (P < 0.05). The yolk sac weight, body weight, and body length had a linear decrease with CLA supplementation (P < 0.05). In the developing chick embryo (at E14) and newly hatched chick (D0), the serum triglyceride concentration decreased with maternal CLA supplementation and was accompanied by a reduction in subcutaneous adipose tissue deposition. In addition, maternal CLA supplementation mediated the hepatic lipid metabolism by decreasing the mRNA expression of sterol regulatory element-binding proteins-1c (SREBP-1c), fatty acid synthase and acetyl-CoA carboxylase, and increasing the mRNA expression of adenosine 5'-monophosphate-activated protein kinase α (AMPKα), peroxisome proliferator-activated receptors α (PPARα), liver fatty acid-binding protein, adipose triglyceride lipase and carnitine palmitoyltransferase in embryonic chick livers (P < 0.05). A drop in SREBP-1c protein expression and an increase in the protein expression of p-AMPKα and PPARα were also observed in the liver of chick embryo (P < 0.05). In conclusion, maternal CLA supplementation regulated the fatty acid composition in the yolk sac, and mediated embryonic chick development and hepatic lipometabolism, and these effects may be related to the AMPK pathway. These findings suggest the potential ability of maternal CLA supplementation to reduce fat deposition in chick embryos.

Polyphenol rich fruit attenuates genomic instability, modulates inflammation and cell cycle progression of offspring from fatty acid intake maternal

The aim of this study was to investigate the effect of juçara (Euterpe edulis Mart.) supplementation on the maternal trans fatty acids intake in the livers of 21-day-old offspring. In order for this to happen, histopathological analysis, cytogenetic status, inflammation (COX-2 and TNF-alpha) and cell cycle progression were investigated in this setting. On the first day of pregnancy, female rats were distributed into four groups, as follows: control diet (C), control diet with 0.5 % juçara supplementation (CJ), diet enriched with hydrogenated vegetable fat, rich in TFAs (T), or T diet supplemented with 0.5 % juçara (TJ) during pregnancy and lactation. Juçara pulp induced liver regeneration in newborns exposed to maternal trans fatty acids. A significant decrease in the number of micronucleated hepatocytes was observed in animals exposed to trans fatty acids and treated with juçara. COX-2 and TNF immunoexpression was reduced in animals treated with juçara pulp. Furthermore, a decrease of Ki-67 immunoexpression was detected after treating trans fatty acids intake with juçara. Taken together, our results demonstrate that juçara pulp is able to prevent tissue degeneration and mutagenicity because it decreases inflammation and cell cycle control induced by maternal trans fatty acids in liver cells of rat offspring.

Maternal and Post-weaning High-Fat Diets Produce Distinct DNA Methylation Patterns in Hepatic Metabolic Pathways within Specific Genomic Contexts

Calorie-dense high-fat diets (HF) are associated with detrimental health outcomes, including obesity, cardiovascular disease, and diabetes. Both pre- and post-natal HF diets have been hypothesized to negatively impact long-term metabolic health via epigenetic mechanisms. To understand how the timing of HF diet intake impacts DNA methylation and metabolism, male Sprague–Dawley rats were exposed to either maternal HF (MHF) or post-weaning HF diet (PHF). At post-natal week 12, PHF rats had similar body weights but greater hepatic lipid accumulation compared to the MHF rats. Genome-wide DNA methylation was evaluated, and analysis revealed 1744 differentially methylation regions (DMRs) between the groups with the majority of the DMR located outside of gene-coding regions. Within differentially methylated genes (DMGs), intragenic DNA methylation closer to the transcription start site was associated with lower gene expression, whereas DNA methylation further downstream was positively correlated with gene expression. The insulin and phosphatidylinositol (PI) signaling pathways were enriched with 25 DMRs that were associated with 20 DMGs, including PI3 kinase (Pi3k), pyruvate kinase (Pklr), and phosphodiesterase 3 (Pde3). Together, these results suggest that the timing of HF diet intake determines DNA methylation and gene expression patterns in hepatic metabolic pathways that target specific genomic contexts.

Maternal high-fat diet impairs leptin signaling and up-regulates type-1 cannabinoid receptor with sex-specific epigenetic changes in the hypothalamus of newborn rats

Maternal nutritional imbalances trigger developmental adaptations involving early epigenetic mechanisms associated with adult chronic disease. Maternal high-fat (HF) diet promotes obesity and hypothalamic leptin resistance in male rat offspring at weaning and adulthood. Leptin resistance is associated with over activation of the endocannabinoid system (ECS). The ECS mainly consists of endocannabinoids derived from n-6 fatty acids and cannabinoid receptors (CB1 coded by Cnr1 and CB2 coded by Cnr2). The CB1 activation in hypothalamus stimulates feeding and appetite for fat while CB2 activation seems to play an immunomodulatory role. We demonstrated that maternal HF diet increases hypothalamic CB1 in male offspring while increases CB2 in female offspring at birth, prior to obesity development. However, the molecular mechanisms behind these changes remain unexplored. We hypothesized that maternal HF diet would down-regulate leptin signaling and up-regulate Cnr1 mRNA levels in the hypothalamus of the offspring at birth, associated with sex-specific changes in epigenetic markers and sex steroid signaling. To test our hypothesis, we used progenitor female rats that received control diet (C, 9% fat) or isocaloric high-fat diet (HF, 28% fat) from 8 weeks before mating until delivery. Blood, hypothalamus and carcass from C and HF male and female offspring were collected for biochemical and molecular analyses at birth. Maternal HF diet down-regulated the transcriptional factor STAT3 in the hypothalamus of male and female offspring, but induced hypoleptinemia only in males and decreased phosphorylated STAT3 only in female offspring. Because leptin acts through STAT3 pathway to inhibit central ECS, our results suggest that leptin pathway impairment might contribute to increased levels of Crn1 mRNA in hypothalamus of both sex offspring. Besides, maternal HF diet increased the histone acetylation percentage of Cnr1 promoter in male offspring and increased the androgen receptor binding to the Cnr1 promoter, which can contribute to higher expression of Cnr1 in newborn HF offspring. Maternal HF diet increased plasma n6 to n3 fatty acid ratio in male offspring, which is an important risk factor to metabolic diseases and might indicate an over activation of endocannabinoid signaling. Thus, although maternal HF diet programs a similar phenotype in adult offspring of both sexes (obesity, hyperphagia and higher preference for fat), here we showed that molecular mechanisms involving leptin signaling, ECS, epigenetic markers and sex hormone signaling were modified prior to obesity development and can differ between newborn male and female offspring. These observations may provide molecular insights into sex-specific targets for anti-obesity therapies.

Fish oil supplementation during adolescence attenuates metabolic programming of perinatal maternal high-fat diet in adult offspring

Perinatal maternal high-fat diet (HFD) increases susceptibility to obesity and fatty liver diseases in adult offspring, which can be attenuated by the potent hypolipidaemic action of fish oil (FO), an n-3 PUFA source, during adult life. Previously, we described that adolescent HFD offspring showed resistance to FO hypolipidaemic effects, although FO promoted hepatic molecular changes suggestive of reduced lipid accumulation. Here, we investigated whether this FO intervention only during the adolescence period could affect offspring metabolism in adulthood. Then, female Wistar rats received isoenergetic, standard (STD: 9 % fat) or high-fat (HFD: 28·6 % fat) diet before mating, and throughout pregnancy and lactation. After weaning, male offspring received the standard diet; and from 25 to 45 d old they received oral administration of soyabean oil or FO. At 150 d old, serum and hepatic metabolic parameters were evaluated. Maternal HFD adult offspring showed increased body weight, visceral adiposity, hyperleptinaemia and decreased hepatic pSTAT3/STAT3 ratio, suggestive of hepatic leptin resistance. FO intake only during the adolescence period reduced visceral adiposity and serum leptin, regardless of maternal diet. Maternal HFD promoted dyslipidaemia and hepatic TAG accumulation, which was correlated with reduced hepatic carnitine palmitoyl transferase-1a content, suggesting lipid oxidation impairment. FO intake did not change serum lipids; however, it restored hepatic TAG content and hepatic markers of lipid oxidation to STD offspring levels. Therefore, we concluded that FO intake exclusively during adolescence programmed STD offspring and reprogrammed HFD offspring male rats to a healthier metabolic phenotype in adult life, reducing visceral adiposity, serum leptin and hepatic TAG content in offspring adulthood.

Maternal high-fat diet consumption induces sex-dependent alterations of the endocannabinoid system and redox homeostasis in liver of adult rat offspring

Maternal diet plays a critical role in health development. Perinatal overnutrition induces metabolic dysfunctions and obesity in the offspring. Obesity is associated with endocannabinoid system (ECS) over activation and oxidative stress. Liver ECS activation induces hepatic steatosis, inflammation and fibrosis while the antagonism of cannabinoid receptors ameliorates these alterations. Here, we investigated the effect of perinatal maternal high-fat diet (HF, 29% of calories as fat) on the ECS and antioxidant system in liver of male and female adult rat offspring (180 days old). Maternal HF diet increased hepatic cannabinoid receptors, ECS metabolizing enzymes and triglyceride content, with male offspring more affected. ECS changes are likely independent of estradiol serum levels but associated with increased hepatic content of estrogen receptor, which can stimulate the expression of ECS components. Differently, maternal HF diet decreased the activity of the antioxidant enzymes glutathione peroxidase, superoxide dismutase and catalase, and increased oxidative stress markers in both sexes. Alterations in the redox homeostasis were associated with mitochondria damage but not with liver fibrosis. Our data suggest that maternal HF diet induces ECS over activation in adulthood, and that male offspring are at higher risk to develop liver disease compared with female rats.

Intrauterine growth restriction combined with a maternal high-fat diet increased adiposity and serum corticosterone levels in adult rat offspring

Intrauterine growth restriction (IUGR) and fetal exposure to a maternal high-fat diet (HFD) independently increase the risk of developing obesity in adulthood. Excess glucocorticoids increase obesity. We hypothesized that surgically induced IUGR combined with an HFD would increase adiposity and glucocorticoids more than in non-IUGR offspring combined with the same HFD, findings that would persist despite weaning to a regular diet. Non-IUGR (N) and IUGR (I) rat offspring from dams fed either regular rat chow (R) or an HFD (H) were weaned to either a regular rat chow or an HFD. For non-IUGR and IUGR rats, this study design resulted in three diet groups: offspring from dams fed a regular diet and weaned to a regular diet (NRR and IRR), offspring rats from dams fed an HFD and weaned to a regular diet (NHR and IHR) and offspring from dams fed an HFD and weaned to an HFD (NHH and IHH). Magnetic resonance imaging or fasting visceral and subcutaneous adipose tissue collection occurred at postnatal day 60. IHH male rats had greater adiposity than NHH males, findings that were only partly normalized by weaning to a regular chow. IHH male rats had a 10-fold increase in serum corticosterone levels. IHH female rats had increased adiposity and serum triglycerides. We conclude that IUGR combined with an HFD throughout life increased adiposity, glucocorticoids and triglycerides in a sex-specific manner. Our data suggest that one mechanism through which the perinatal environment programs increased adiposity in IHH male rats may be via increased systemic glucocorticoids.

Diet in pregnancy-more than food

High food quality, together with adequate macro- and micronutrient intake in pregnancy, is crucial for the health status of the mother and child. Recent findings suggest that it could also be beneficial or harmful in the context of the well-being of the whole future population. According to the developmental origins of health and disease hypothesis, most conditions that occur in adulthood originate in foetal life. Moreover, some epigenetic events, modified inter alia by diet, impact more than one generation. Still, the recommendations in most countries are neither popularised nor very detailed. While it seems to be important to direct diet trends towards a healthier lifestyle, the methods of preventing specific disorders like diabetes or asthma are not yet established and require further investigation.

CONCLUSION

In this review, we will summarise the recommendations for diet composition in pregnancy, focusing on both diet quality and quantity. What is Known • High food quality, together with adequate macro- and micronutrient intake in pregnancy, is crucial for the health status of the mother and child. What is New • Recent findings suggest that the diet could be beneficial or harmful in the context of the well-being of the whole future population. Most conditions that occur in adulthood originate in foetal life. • Moreover, some epigenetic events, modified by diet impact more than one generation.

Maternal conjugated linoleic acid modulates TAG metabolism in adult rat offspring

Conjugated linoleic acid (CLA) might regulate the lipid depots in liver and adipose tissue. As there is an association between maternal nutrition, fat depots and risk of offspring chronic disease, the aim was to investigate the effect of maternal CLA consumption on TAG regulation and some inflammatory parameters in adult male rat offspring receiving or not receiving CLA. Female Wistar rats were fed control (C) or CLA-supplemented (1 %, w/w) diets during 4 weeks before and throughout pregnancy and lactation. After weaning, male offspring of CLA rats were fed C or CLA diets (CLA/C and CLA/CLA groups, respectively), whereas C male rat offspring were fed a C diet (C/C group) for 9 weeks. Serum TAG levels were increased in the CLA/CLA and CLA/C groups, associated with a reduction of lipoprotein lipase activity and weights of adipose tissue. The liver TAG levels were decreased in the CLA/CLA group, related to a significant reduction of fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC) and glucose-6-phosphate dehydrogenase enzyme activities, as well as to the mRNA levels of FAS, ACC, stearoyl-CoA desaturase-1 and sterol regulatory element-binding protein-1c. Even though normal TAG levels were found in the liver of CLA/C rats, a reduction of lipogenesis was also observed. Thus, these results demonstrated a programming effect of CLA on the lipid metabolic pathways leading to a preventive effect on the TAG accretion in adipose tissue and the liver of male rat offspring. This knowledge could be important to develop some dietary strategies leading to a reduced incidence of obesity and fatty acid liver disease in humans.

Perinatal maternal high-fat diet induces early obesity and sex-specific alterations of the endocannabinoid system in white and brown adipose tissue of weanling rat offspring

Perinatal maternal high-fat (HF) diet programmes offspring obesity. Obesity is associated with overactivation of the endocannabinoid system (ECS) in adult subjects, but the role of the ECS in the developmental origins of obesity is mostly unknown. The ECS consists of endocannabinoids, cannabinoid receptors (cannabinoid type-1 receptor (CB1) and cannabinoid type-2 receptor (CB2)) and metabolising enzymes. We hypothesised that perinatal maternal HF diet would alter the ECS in a sex-dependent manner in white and brown adipose tissue of rat offspring at weaning in parallel to obesity development. Female rats received standard diet (9 % energy content from fat) or HF diet (29 % energy content from fat) before mating, during pregnancy and lactation. At weaning, male and female offspring were killed for tissue harvest. Maternal HF diet induced early obesity, white adipocyte hypertrophy and increased lipid accumulation in brown adipose tissue associated with sex-specific changes of the ECS's components in weanling rats. In male pups, maternal HF diet decreased CB1 and CB2 protein in subcutaneous adipose tissue. In female pups, maternal HF diet increased visceral and decreased subcutaneous CB1. In brown adipose tissue, maternal HF diet increased CB1 regardless of pup sex. In addition, maternal HF diet differentially changed oestrogen receptor across the adipose depots in male and female pups. The ECS and oestrogen signalling play an important role in lipogenesis, adipogenesis and thermogenesis, and we observed early changes in their targets in adipose depots of the offspring. The present findings provide insights into the involvement of the ECS in the developmental origins of metabolic disease induced by inadequate maternal nutrition in early life.

Maternal high-fat diet impairs glucose metabolism, β-cell function and proliferation in the second generation of offspring rats

Background

This study aimed to assess the impact of perinatal high-fat (HF) diet in female Sprague-Dawley rats (F0) on glucose metabolism and islet function in their early life of second-generation of offspring (F2).

Methods

F0 rats were fed with a standard chow (SC) or HF diet for 8 weeks before mating, up to termination of lactation for their first-generation of offspring (F1-SC and F1-HF). F1 females were mated with normal males at the age of week 11, and producing F2 offspring (F2-SC, F2-HF). All the offspring were fed SC diet after weaning for 3 weeks. The glucose level and islet function of F2 offspring were assessed at the age of week 3 and 12.

Results

The F2-HF offspring had a high birth weight and maintained a higher body mass at the age of week 3 and 12, along with an impaired glucose tolerance and lower serum insulin levels compared with the F2-SC. β-cell proliferation was also impaired in the islets of F2-HF rats at the age of week 3 and 12. The pancreatic and duodenal homeobox factor-1 (Pdx1) and Neurogenic differentiation 1 (NeuroD1) expressions were decreased in the islet of F2-HF rats at the age of week 12.

Conclusions

Maternal HF diet during pre-gestation, gestation, and lactation in rats could result in the increased body weight and glucose intolerance in their early life of F2 offspring due to impaired β-cell function and proliferation.

Different combinations of maternal and postnatal diet are reflected in changes of hepatic parenchyma and hepatic TNF-alpha expression in male rat offspring

Obesity is related to increased TNF-alpha production in different tissues. TNF-alpha is connected to mitochondrial dysfunction in the liver and also development of fatty infiltration of the liver. Also, postnatal change from normal to high-fat diet causes a significant increase in TNF-alpha serum levels. The aim of this research was to determine how maternal diet and switching male offspring to a different dietary regime after lactation influences rat liver. Ten female Sprague Dawley rats at nine weeks of age were randomly divided in two groups and fed either standard laboratory chow or high-fat diet during six weeks, and then mated with the same male subject. After birth and lactation male offspring from both groups were further divided into four subgroups depending on their subsequent diet. At 22 weeks of age, the animals were weighted, sacrificed and major organs were collected and weighted. Immunohistochemistry for TNF-alpha was performed on liver, and liver samples were analyzed for pathohistological changes. The group in which mothers were fed standard chow and offspring high-fat diet had the most pronounced changes: heaviest liver, poorest histopathological findings and strongest TNF-alpha immunohistochemical staining of liver parenchyma. High-fat diet during pregnancy and lactation and switching to high-fat diet postnatally affects liver weight, histological structure and TNF-alpha expression in male offspring.