Maternal diet high in fat reduces docosahexaenoic acid in liver lipids of newborn and sucking rat pups

Rodent models of obesity

Obese or overweight people exceed one-third of the global population and obesity along with diabetes mellitus consist basic components of metabolic syndrome, both of which are known cardio-cerebrovascular risk factors with detrimental consequences. These data signify the pandemic character of obesity and the necessity for effective treatments. Substantial advances have been accomplished in preclinical research of obesity by using animal models, which mimic the human disease. In particular, rodent models have been widely used for many decades with success for the elucidation of the pathophysiology of obesity, since they share physiological and genetic components with humans and appear advantageous in their husbandry. The most representative rodents include the laboratory mouse and rat. Within this review, we attempted to consolidate the most widely used mice and rat models of obesity and highlight their strengths as well as weaknesses in a critical way. Our aim was to bridge the gap between laboratory facilities and patient's bed and help the researcher find the appropriate animal model for his/her obesity research. This tactful selection of the appropriate model of obesity may offer more translational derived results. In this regard, we included, the main diet induced models, the chemical/mechanical ones, as well as a selection of monogenic or polygenic models.

High-fat diet in pregnant rats and adverse fetal outcome

Background: Although pregestational obesity has been associated with increased risk of adverse fetal outcome, the mechanisms behind are not known. We aimed to investigate the influence of the maternal metabolic state on fetal outcome in rats exposed to either a high-fat diet (HFD) or a control diet (CD). We also investigated the impact of serum collected from HFD/CD pregnant rats on CD embryonic development in whole-embryo cultures. Material and methods: On gestational day 0, 9, 10, or 20 maternal plasma/serum samples were collected as pregnancies were terminated for the estimations of maternal metabolic state and embryo-fetal development. We measured embryonic gene expression of ROS scavenger enzymes as well as genes involved in inflammation in maternal adipose tissue. Results: In HFD maternal plasma/serum, concentrations of glucose, β-hydroxybutyrate, branched-chain amino acids, and leptin were increased, whereas those of triacylglycerol, cholesterol, and palmitic, oleic, linoleic, and α-linolenic acids were decreased. Gene expression of CuZnSOD, IL-6, IL-10, and resistin was increased in HFD maternal adipose tissue, whereas that of CuZnSOD and MnSOD was decreased in HFD-exposed embryos. HFD caused retention of most fatty acids in the maternal liver as well. Conclusion: HFD alters the maternal metabolic state, increases fetal resorptions in vivo, and increases the rate of fetal/embryonic malformations both in vivo and in vitro. These findings suggest that metabolic disturbances in HFD pregnant rats have profound adverse developmental effects in the offspring.

Concentrations of docosahexaenoic acid are reduced in maternal liver, adipose, and heart in rats fed high-fat diets without docosahexaenoic acid throughout pregnancy

Fetal accretion for DHA is high during late pregnancy due to the brain growth spurt. Prior evidence suggests that DHA is mobilized from maternal liver and adipose to meet fetal accretion and physiological requirements. However, changes in the DHA levels of various maternal tissues throughout pregnancy and into lactation of mothers on diets with and without dietary DHA, and with a background dietary fatty acid profile that resembles human intake has not been examined. Sprague Dawley rats were fed a total western diet with (TWD + ) or without DHA (TWD-) along with a commercial rodent chow control (Chow) throughout pregnancy and postpartum. The fatty acid compositions of adipose, brain, heart, liver, erythrocytes, and plasma were determined before pregnancy, at 15 and 20 days of pregnancy, and 7 days postpartum. The placenta, fetuses, and pups were also examined when available. Maternal DHA concentrations were increased in plasma at 20 days pregnancy in all the diets with TWD + > Chow > TWD-. Maternal DHA concentrations in the TWD- group were lower in adipose throughout pregnancy as compared with the other diets. At postpartum, DHA concentrations decreased below baseline levels in the heart of the TWD- and Chow dams and the liver of the TWD- dams. Whole body DHA concentrations of the fetuses did not differ but there was evidence of decreased DHA in the whole body and tissues of the TWD- and Chow 7d old pups. In conclusion, it appears that in this rodent model of pregnancy, maternal adaptations were made to meet fetal DHA requirements, but they may compromise maternal DHA status and the ability to deliver DHA during lactation.

Cocos nucifera water improves metabolic functions in offspring of high fat diet fed Wistar rats

BACKGROUND

Maternal high fat diet has been implicated in the aetiology of metabolic diseases in their offspring. The hypolipidaemic actions of Cocos nucifera water improve metabolic indices of dams consuming a high fat diet during gestation. This study investigated the effects of C. nucifera water on metabolism of offspring of dams exposed to high fat diet during gestation.

METHODS

Four groups of pregnant Wistar rat dams (n=6) were treated orally from Gestation Day (GD) 1 to GD 21 as follows: standard rodent feed+10 mL/kg distilled water (Control), standard rodent feed+10 mL/kg C. nucifera water, high fat feed+10 mL/kg distilled water (high fat diet), and high fat feed+10 mL/kg C. nucifera water (high fat diet+C. nucifera water). The feeds were given ad libitum and all dams received standard rodent feed after parturition. Fasting blood glucose was measured in offspring before being euthanized on Postnatal Day (PND) 120. Serum insulin, leptin, lipid profile and liver enzymes were measured.

RESULTS

Serum total cholesterol (TC), insulin, alanine transaminase (ALT) and alkaline phosphatase levels were significantly increased (p<0.05) in high fat diet offspring compared with controls. Similar changes were not observed in high fat diet+C. nucifera water offspring.

CONCLUSIONS

Results suggest that the adverse effects of maternal high fat diet on offspring's metabolism can be ameliorated by C. nucifera water.

Maternal high-fat diet influences outcomes after neonatal hypoxic-ischemic brain injury in rodents

The typical US diet has >30% calories from fat; yet, typical laboratory diets contain 17% calories from fat. This disparity could confound the clinical relevance of findings in cerebral ischemia models. We compared outcomes after neonatal brain injury in offspring of rat dams fed standard low-fat chow (17% fat calories) or a higher fat diet (34% fat calories) from day 7 of pregnancy. On postnatal day 7, hypoxic-ischemic injury was induced by right carotid ligation, followed by 60, 75 or 90 min 8% oxygen exposure. Sensorimotor function, brain damage, and serum and brain fatty acid content were compared 1 to 4 weeks later. All lesioned animals developed left forepaw placing deficits; scores were worse in the high-fat groups (p < 0.0001, ANOVA). Similarly, reductions in left forepaw grip strength were more pronounced in the high-fat groups. Severity of right hemisphere damage increased with hypoxia-ischemia duration but did not differ between diet groups. Serum and brain docosahexaenoic acid fatty acid fractions were lower in high-fat progeny (p < 0.05, ANOVA). We speculate that the high-fat diet disrupted docosahexaenoic acid-dependent recovery mechanisms. These findings have significant implications both for refinement of neonatal brain injury models and for understanding the impact of maternal diet on neonatal neuroplasticity.

High Fat Diet Administration during Specific Periods of Pregnancy Alters Maternal Fatty Acid Profiles in the Near-Term Rat

Excessive fat intake is a global health concern as women of childbearing age increasingly ingest high fat diets (HFDs). We therefore determined the maternal fatty acid (FA) profiles in metabolic organs after HFD administration during specific periods of gestation. Rats were fed a HFD for the first (HF1), second (HF2), or third (HF3) week, or for all three weeks (HFG) of gestation. Total maternal plasma non-esterified fatty acid (NEFA) concentrations were monitored throughout pregnancy. At day 20 of gestation, maternal plasma, liver, adipose tissue, and placenta FA profiles were determined. In HF3 mothers, plasma myristic and stearic acid concentrations were elevated, whereas docosahexaenoic acid (DHA) was reduced in both HF3 and HFG mothers. In HF3 and HFG mothers, hepatic stearic and oleic acid proportions were elevated; conversely, DHA and linoleic acid (LA) proportions were reduced. In adipose tissue, myristic acid was elevated, whereas DHA and LA proportions were reduced in all mothers. Further, adipose tissue stearic acid proportions were elevated in HF2, HF3, and HFG mothers; with oleic acid increased in HF1 and HFG mothers. In HF3 and HFG mothers, placental neutral myristic acid proportions were elevated, whereas DHA was reduced. Further, placental phospholipid DHA proportions were reduced in HF3 and HFG mothers. Maintenance on a diet, high in saturated fat, but low in DHA and LA proportions, during late or throughout gestation, perpetuated reduced DHA across metabolic organs that adapt during pregnancy. Therefore a diet, with normal DHA proportions during gestation, may be important for balancing maternal FA status.

Pathophysiological basis for compromised health beyond generations: role of maternal high-fat diet and low-grade chronic inflammation

Early exposure to a fat-enriched diet programs the developmental profile and thus is associated with disease susceptibility in subsequent generations. Chronic low-grade inflammation, resulting from maternal high-fat diet, is activated in the fetal environment and in many organs of offspring, including placenta, adipose, liver, vascular system and brain. The prevalence of an inflammatory response is highly associated with obesity incidence, cardiovascular diseases, nonalcoholic fatty liver disease and brain damage. Substantial studies using high-fat model have consistently demonstrated the incidence of such inflammatory reactions; however, the potential contribution of active inflammation toward the physiological outcomes and developmental diseases is neither discussed in depth nor systemically integrated. Therefore, we aim to summarize the current findings in regards to how a maternal high-fat diet influences the inflammatory status, and probable pathogenic effects on the offspring. More importantly, since limited research has been conducted to reveal the epigenetic regulation of these inflammatory markers by maternal high-fat diet, we sincerely hope that our review will not only outline the pathophysiological relevance of inflammation but also identify a future direction for mechanistic investigation and clinical application.

Transgenerational healing: Educating children in genesis of healthy children, with focus on nutrition, emotion, and epigenetic effects on brain development

Although our continuing evolution can never achieve our perfection, we long for our children's birth and health to be near-perfect. Many children are born healthy, though fewer than is possible. Birthing and health rapidly improved generally due to modern housing, sanitation and medicine, as well as birth interventions. Arguably interventions have exceeded the optimal level, without enough regard for natural physical and intuitive resources. Conception, often too easy, receives too little personal preparation unless a couple has problems. Nurturing the health of sperm and ovum seems hard to focus on, yet is needed by both parents - and even by the four grandparents. What are the key factors? Positive: The fields of hormones/emotions and of nutrition/metabolism. Negative: stress, poor nutrition, toxins, diseases; much being due to poverty. Positive and negative both have structural and also epigenetic effects. Interventions, essential or inessential, are seldom without negative side effects. Health can best, and most economically, be generated at the beginning of life, through healthy conception, gestation and birth. Understanding prime needs improves initial health. It also informs therapy of any early-life problems. Healing is therefore more efficient when transgenerational, and much more powerful than individual healing. My vision of healing is safeguarding our evolution in progress. Children's choices - eating, exercise, emotional attitudes and relationships - are already profoundly affecting any children they may have, their mental and physical health. The most practical starting point seems to be educating boys as well as girls. Childhood is therefore the time to educate them in choices. The correction of often unnoticed problems- nutrient deficits, toxins, uro-genital disease - has enabled nearly nine out of ten couples to bear fully healthy babies, even following severe problems - infertility, miscarriages, stillbirths and malformations. Correcting problems before conception prevents both structural faults and wrong setting of gene-switches. Children's habits set. Once courting most are preoccupied and many pregnant unintentionally. Childhood is the time to be adopting a healthy lifestyle, the way to healthy babies The mother's nutritional and emotional status throughout pregnancy continues to affect her child's future physical and mental health, behaviour and ability. Before conception a woman needs to build her appropriate body stores - vitamins and minerals, proteins, docosahexaenoic acid. Before bearing another child, a replenishment time of 3 years is desirable. A return to childbearing in the 20s and early 30s could reduce risks that have risen with the recent shift towards conception by school children and by women in their late 30s or more. Governments, schoolteachers, health professionals, need to adopt this policy of transgenerational health. Empowerment with knowledge is the one way to fend off the growing pandemic of mental ill health and related disorders and to make the most of a nation's genetic potential. Financially there could be no better investment, let alone in enhancing people's lives. Childhood is the most appropriate time for education in this way to generating a healthy, able and peaceful human race. Essential to our amazing genetic systems are the resources of land, sea and air. We are one with our biosphere. We need urgently to follow up the vital work of Developmental Origins of Health and Disease, and of Far East initiatives in sea-bed and sea husbandry.

Effect of high-fat diet prior to pregnancy on hepatic gene expression and histology in mouse offspring

Maternal overnutrition and obesity are associated with fetal development and cause long-term effects in offspring. However, the effects of a high-fat diet specific to the pre-pregnancy period are not determined. The present study aimed to examine the effect of high-fat diet prior to pregnancy on the liver of mouse offspring. Female C57BL/6J mice were fed a normal chow (15.2% fat by energy) [control diet (CTR) and CTR pre-pregnancy (PP) groups] or a high-fat chow (31.2% fat by energy) [high-fat diet (HFD) and HFD-pre-pregnancy (PP) groups] for 3-4 weeks and then mated with male C57BL/6J mice fed normal chow. Some mothers continued on the same diet until pups reached 21 days of age (CTR and HFD), and others were fed the different chows from gestational day 0 (CTR-PP and HFD-PP) to determine the effects of a high-fat diet during the pre-pregnancy period in HFD-PP/CTR and HFD/CTR-PP comparisons. Liver tissues from pups were subjected to gene expression analysis by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and microarray, and histological analysis using Oil Red O staining (Sigma Chemical Co., Ltd., Balcatta, WA, USA). Lipid droplets were increased in hepatocytes of mice in HFD-PP compared to CTR and those in HFD compared to CTR-PP. Expression of stearoyl-coenzyme A desaturase 1 (Scd1), acetyl-coenzyme A carboxylase beta (Acacb), and fatty acid binding protein 5 (Fabp5) was increased by maternal high-fat diet during pre-pregnancy. The results showed that maternal high-fat diet intake prior to pregnancy uniquely affects metabolic phenotype related to health and disease in the liver of the next generation.

Streptozotocin-induced diabetes partially attenuates the effects of a high-fat diet on liver and brain fatty acid composition in mice

The current study addresses the effects of a high-fat diet on liver and brain fatty acid compositions and the interaction of that diet with diabetes in a type 1 mouse model. Adult, male, normal and streptozotocin-induced diabetic C57BL/6 mice were fed standard (14 % kcal from fat) or high-fat (54 % kcal from fat, hydrogenated vegetable shortening and corn oil) diets for 8 weeks. Liver and whole brain total phospholipid fatty acid compositions were then determined by TLC/GC. In the liver of non-diabetic mice, the high-fat diet increased the percentages of 18:1n-9, 20:4n-6, and 22:5n-6 and decreased 18:2n-6 and 22:6n-3. Diabetes increased 16:0 in liver, and decreased 18:1n-7 and 20:4n-6. The effects of the high-fat diet on liver phospholipids in diabetic mice were similar to those in non-diabetic mice, or were of smaller magnitude. In the brain, the high-fat diet increased 18:0 and 20:4n-6 of non-diabetic, but not diabetic mice. Brain 22:5n-6 acid was increased by the high-fat diet in both non-diabetic and diabetic mice, but this increase was smaller in diabetic mice. Diabetes alone did not alter the percentage of any individual fatty acid in brain. This indicates that the effects of a high-fat diet on liver and brain phospholipid fatty acid compositions are partially attenuated by concomitant hyperglycemia with hypoinsulinemia.

Animal models of in utero exposure to a high fat diet: a review

The incidence of metabolic disease, including type 2 diabetes and obesity, has increased to epidemic levels in recent years. A growing body of evidence suggests that the intrauterine environment plays a key role in the development of metabolic disease in offspring. Among other perturbations in early life, alteration in the provision of nutrients has profound and lasting effects on the long term health and well being of offspring. Rodent and non-human primate models provide a means to understand the underlying mechanisms of this programming effect. These different models demonstrate converging effects of a maternal high fat diet on insulin and glucose metabolism, energy balance, cardiovascular function and adiposity in offspring. Furthermore, evidence suggests that the early life environment can result in epigenetic changes that set the stage for alterations in key pathways of metabolism that lead to type 2 diabetes or obesity. Identifying and understanding the causal factors responsible for this metabolic dysregulation is vital to curtailing these epidemics. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.

A maternal high-fat diet represses the expression of antioxidant defense genes and induces the cellular senescence pathway in the liver of male offspring rats

Maternal high-fat (HF) diet feeding is associated with increased risk of developing metabolism-related diseases in adult offspring, including chronic liver disease. The present study tested the hypothesis that maternal HF diet leads to a decreased antioxidant defense capacity and causes cellular senescence in liver of adult offspring rats, which might increase risk of developing chronic liver disease. Timed-pregnant Sprague Dawley rats were fed a HF diet (45% of energy from fat) or a control (C) diet (16% of energy from fat) during gestation and lactation. The resulting offspring were fed a C diet after weaning to generate 2 offspring groups: C diet-fed offspring of dams fed C diet (C/C) and C diet-fed offspring of dams fed a HF diet (HF/C). At 12 wk of age, male rats were killed and samples were collected for analysis. Maternal HF diet significantly increased plasma TG and hepatic TBARS concentrations and the size of hepatic lipid droplets in offspring rats. The expression of antioxidant defense genes, such as glutathione peroxidase-1, Cu/Zn superoxide dismutase (Sod1), paraoxonase enzymes (Pon1, Pon2, and Pon3), were significantly lower in the liver of HF/C pups than in C/C pups. The expression of Inhibitor of cyclin dependent Kinase 4a (p16INK4a), a marker of cellular senescence, and cyclooxygenase-2 (Cox2), a proinflammatory marker, was significantly higher in the HF/C offspring group than in the C/C offspring group. Western-blot analysis shows that cyclin D1 and phosphorylated retinoblastoma protein were significantly lower in HF/C offspring than in C/C offspring. The results provide the first evidence to our knowledge that maternal HF diet might alter antioxidant defense capacity and program the p16INK4a-dependent cellular senescence in the liver of adult offspring.

Animal models in diabetes and pregnancy

The worldwide increase in the incidence of diabetes, the increase in type 2 diabetes in women at reproductive ages, and the cross-generation of the intrauterine programming of type 2 diabetes are the bases for the growing interest in the use of experimental diabetic models in order to gain insight into the mechanisms of induction of developmental alterations in maternal diabetes. In this scenario, experimental models that present the most common features of diabetes in pregnancy are highly required. Several important aspects of human diabetic pregnancies such as the increased rates of spontaneous abortions, malformations, fetoplacental impairments, and offspring diseases in later life can be approached by using the appropriate animal models. The purpose of this review is to give a practical and critical guide into the most frequently used experimental models in diabetes and pregnancy, discuss their advantages and limitations, and describe the aspects of diabetes and pregnancy for which these models are thought to be adequate. This review provides a comprehensive view and an extensive analysis of the different models and phenotypes addressed in diabetic animals throughout pregnancy. The review includes an analysis of the surgical, chemical-induced, and genetic experimental models of diabetes and an evaluation of their use to analyze early pregnancy defects, induction of congenital malformations, placental and fetal alterations, and the intrauterine programming of metabolic diseases in the offspring's later life.

Modern organic and broiler chickens sold for human consumption provide more energy from fat than protein

Objective

In 1976, the Royal College of Physicians and the British Cardiac Society recommended eating less fatty red meat and more poultry instead because it was lean. However, the situation has changed since that time, with a striking increase in fat content of the standard broiler chicken. The aim of the present study was to report a snapshot of data on fat in chickens now sold to the public.

Design

Samples were obtained randomly between 2004 and 2008 from UK supermarkets, farm shops and a football club. The amount of chicken fat was estimated by emulsification and chloroform/methanol extraction.

Setting

Food sold in supermarkets and farms in England.

Subjects

Chicken samples.

Results

The fat energy exceeded that of protein. There has been a loss ofn-3 fatty acids. Then-6:n-3 ratio was found to be as high as 9:1, as opposed to the recommendation of about 2:1. Moreover, the TAG level in the meat and whole bird mostly exceeded the proportion of phospholipids, which should be the higher for muscle function. Then-3 fatty acid docosapentaenoic acid (DPA, 22 : 5n-3) was in excess of DHA (22 : 6n-3). Previous analyses had, as usual for birds, more DHA than DPA.

Conclusions

Traditional poultry and eggs were one of the few land-based sources of long-chainn-3 fatty acids, especially DHA, which is synthesized from its parent precursor in the green food chain. In view of the obesity epidemic, chickens that provide several times the fat energy compared with protein seem illogical. This type of chicken husbandry needs to be reviewed with regard to its implications for animal welfare and human nutrition.

Maternal dietary supplementation with saturated, but not monounsaturated or polyunsaturated fatty acids, leads to tissue-specific inhibition of offspring Na+,K+-ATPase

In rats, a maternal diet rich in lard is associated with reduced Na(+),K(+)-ATPase activity in adult offspring kidney. We have addressed the role of different fatty acids by evaluating Na(+),K(+)-ATPase activity in offspring of dams fed diets rich in saturated (SFA), monounsaturated (MUFA) or polyunsaturated (PUFA) fatty acids. Female Sprague-Dawley rats were fed, during pregnancy and suckling, a control diet (4% w/w corn oil) or a fatty acid supplemented diet (24% w/w). Offspring were reared on chow (4% PUFA) and studied at 6 months. mRNA expression (real-time PCR) of Na(+),K(+)-ATPase alpha subunit and protein expression of Na(+),K(+)-ATPase subunits (Western blot) were assessed in kidney and brain. Na(+),K(+)-ATPase activity was reduced in kidney (P < 0.05 versus all groups) and brain (P < 0.05 versus control and MUFA offspring) of the SFA group. Neither Na(+),K(+)-ATPase alpha1 subunit mRNA expression, nor protein expression of total alpha, alpha1, alpha2, alpha3 or beta1 subunits were significantly altered in kidney in any dietary group. In brains of SFA offspring alpha1 mRNA expression (P < 0.05) was reduced compared with MUFA and PUFA offspring, but not controls. Also in brain, SFA offspring demonstrated reduced (P < 0.05) alpha1 subunit protein and increased phosphorylation (P < 0.05) of the Na(+),K(+)-ATPase modulating protein phospholemman at serine residue 63 (S63 PLM). Na(+),K(+)-ATPase activity was similar to controls in heart and liver. In utero and neonatal exposure to a maternal diet rich in saturated fatty acids is associated with altered activity and expression of Na(+),K(+)-ATPase in adulthood, but mechanisms appear tissue specific.

Maternal high-fat diet consumption results in fetal malprogramming predisposing to the onset of metabolic syndrome-like phenotype in adulthood

Chronic consumption of a high-fat (HF) diet by female rats in their postweaning period resulted in significant increases in body weight and plasma levels of insulin, glucose, and triglycerides during pregnancy compared with female rats consuming a standard rodent laboratory chow (LC). On gestational day 21, plasma insulin levels and the insulin secretory response of islets to various secretogogues were significantly increased in HF fetuses. The HF male progeny weaned onto LC (HF/LC) demonstrated increases in body weight from postnatal day 60 onward. In adulthood, HF/LC male rats were significantly heavier than controls, had increased plasma levels of insulin, glucose, free fatty acids, and triglycerides, and demonstrated glucose intolerance. HF/LC male islets secreted increased amounts of insulin in response to low glucose concentrations, but their response to a high glucose concentration was similar to that of LC/LC islets. In another set of experiments, when the male progeny of HF female rats were weaned onto a high-sucrose diet (HF/HSu), their metabolic profile was further worsened. These results indicate that chronic consumption of a HF diet by female rats malprograms the male progeny for glucose intolerance and development of increased body weight in adulthood. The long-term high-fat feeding to female rats employed in this study bears resemblance to the dietary habits in Western societies. The results of this study implicate dietary practices of women in the etiology of the present epidemic of human obesity and related disorders.

Developmental programming of aortic and renal structure in offspring of rats fed fat-rich diets in pregnancy

Evidence from human and animal studies suggests that maternal nutrition can induce developmental programming of adult hypertension in offspring. We have previously described a model of maternal dietary imbalance in Sprague-Dawley rats whereby administration of a maternal diet rich in animal lard programmes the development of increased blood pressure, insulin resistance, dyslipidaemia, obesity and mesenteric artery endothelial dysfunction in adult offspring. To further characterize the mechanism of hypertension in this model we have examined vascular and renal structure in adult offspring of Sprague-Dawley rats fed a control diet (OC) or lard-rich diet (OHF) during pregnancy and suckling followed by a control diet post-weaning. To gain further insight, we assessed aortic reactivity and elasticity in an organ bath preparation and renal renin and Na+,K+-ATPase activity. Plasma aldosterone concentration was also measured. Stereological examination of the aorta in OHF demonstrated reduced endothelial cell volume and smooth muscle cell number compared with OC. Adult OHF animals showed increased aortic stiffness and reduced endothelium-dependent relaxation. Renal stereology showed no differences in kidney weight, glomerular number or volume in OHF compared with OC, but renin and Na+,K+-ATPase activity were significantly reduced in OHF compared with controls. Programmed alterations to aortic structure and function are consistent with previous observations that exposure to maternal high fat diets produces systemic vascular changes in the offspring. Despite normal renal stereology, altered renal Na+,K+-ATPase and renin activity offers further insight into the mechanism underlying the increased blood pressure characteristic of this model.

Intrauterine vascular development: programming effects of nutrition on vascular function in the new born and adult

The importance of the Barker hypothesis, relating faulty maternal nutrition to low birth weight and subsequent disease in adult life, is examined in relation to vascular function.

Liver triacylglycerols and free fatty acids in streptozotocin-induced diabetic rats have atypical n-6 and n-3 pattern

In diabetes there is a decrease in membrane arachidonic (AA) and docosahexaenoic (DHA) acids and a concomitant increase in linoleic (LA) and alpha-linolenic (ALA) acids. This metabolic perturbation is thought to be due to impaired activity of Delta(6)- and Delta(5)-desaturases. Triacylglycerols are the major lipid pool in plasma and liver tissue and have a significant influence on fatty acid composition of membrane and circulating phospholipids. Data on the distribution of n-6 and n-3 polyunsaturated fatty acids of triacylglycerols in diabetes are sparse. We investigated whether streptozotocin-induced diabetes in Sprague-Dawley rats alters fatty acid composition of triacylglycerols and free fatty acids of liver tissue. The animals were fed a breeding diet prior to mating, during pregnancy and lactation. On days 1-2 of pregnancy, diabetes was induced in 10 of the 25 rats. Liver was obtained at post partum day 16 for analysis. Relative levels of LA (P=0.03), dihomo-gamma-linolenic acid (DHGLA) (P=0.02), AA (P=0.049), total n-6 (P=0.02), ALA (P=0.013), eicosapentaenoic acid (EPA) (P=0.004), docosapentaenoic acid (22:5n-3, DPA) (P=0.013), DHA (P=0.033), n-3 metabolites (P=0.015) and total n-3 (P=0.011) were significantly higher in the triacylglycerols of the diabetics compared with the controls. Similarly, liver free fatty acids of the diabetics had higher levels of LA (P=0.0001), DHGLA (P=0.001), AA (P=0.001), n-6 metabolites (P=0.002), total n-6 (P=0.0001), ALA (P=0.003), EPA (P=0.015), docosapentaenoic (22:5n-3, P=0.003), DHA (P=0.002), n-3 metabolites (P=0.005) and total n-3 (P=0.001). We conclude that impaired activity of desaturases and/or long chain acyl-CoA synthetase could not explain the higher levels of AA, DHA and n-6 and n-3 metabolites in the diabetics. This seems to be consistent with an alteration in the regulatory mechanism, which directs incorporation of polyunsaturated fatty acids either into triacylglycerols or phospholipids.

Abnormal aortic fatty acid composition and small artery function in offspring of rats fed a high fat diet in pregnancy

1. Disturbances of the in utero environment are associated with an increased risk of cardiovascular disease in adulthood. In this study we have determined whether abnormal vascular function in the adult offspring of rats fed a high saturated fat diet in pregnancy is associated with altered plasma lipids or vascular fatty acid content. 2. Female Sprague-Dawley rats were fed a breeding diet (4 % fat) or a diet high in saturated fat (20 % fat) for 10 days prior to and throughout pregnancy, and during weaning. Female offspring were then fed a maintenance diet (3 % fat) until 160 days of age. 3. Endothelium-dependent relaxation induced by acetylcholine was blunted in isolated branches of the femoral artery from 160-day-old female offspring of dams fed the saturated fat diet when compared with female offspring of dams fed the breeding diet. These offspring exhibited elevated plasma triglyceride and reduced plasma high density lipoprotein cholesterol concentrations. 4. The fatty acid composition of the aortas was abnormal, with a marked reduction in the content of arachidonic and docosahexaenoic acids. 5. This study demonstrates that a high fat diet in pregnant rats produces abnormal vascular function, plasma lipid disturbances and altered vascular fatty acid content in their female offspring during adulthood.

Phospholipid metabolism and depression: the possible roles of phospholipase A2 and coenzyme A-independent transacylase

Phospholipids make up 60 per cent of the dry weight of the brain. They are essential for neuronal and especially for synaptic structure and play key roles in the signal transduction responses to dopamine, serotonin, glutamate and acetyl choline. The unsaturated fatty acid components of phospholipids are abnormal in depression, with deficits of eicosapentaenoic acid and other omega-3 fatty acids and excesses of the omega-6 fatty acid arachidonic acid. Correction of this abnormality by treatment with eicosapentaenoic acid improves depression. The fatty acid abnormalities provide a rational explanation for the associations of depression with cardiovascular disease, immunological activation, cancer, diabetic complications and osteoporosis. The abnormalities cannot be explained by diet, although diet may attenuate or exacerbate their consequences. A number of enzyme abnormalities could explain the phenomena: phospholipase A(2), and coenzyme A-independent transacylase are strong candidates. Copyright 2001 John Wiley & Sons, Ltd.

Secondary carnitine deficiency and impaired docosahexaenoic (22:6n-3) acid synthesis: a common denominator in the pathophysiology of diseases of oxidative phosphorylation and beta-oxidation

A critical analysis of the literature of mitochondrial disorders reveals that genetic diseases of oxidative phosphorylation are often associated with impaired beta-oxidation, and vice versa, and preferentially affect brain, retina, heart and skeletal muscle, tissues which depend on docosahexaenoic (22:6n-3)-containing phospholipids for functionality. Evidence suggests that an increased NADH/NAD(+) ratio generated by reduced flux through the respiratory chain inhibits beta-oxidation, producing secondary carnitine deficiency while increasing reactive oxygen species and depleting alpha-tocopherol (alpha-TOC). These events result in impairment of the recently elucidated mitochondrial pathway for synthesis of 22:6n-3-containing phospholipids, since carnitine and alpha-TOC are involved in their biosynthesis. Therapeutic supplementation with 22:6n-3 and alpha-TOC is suggested.