High Fat Diets and Obesity Possible Influence of n3 PUFAs

Obesity is one of the major health risks for a number of diseases, particularly heart disease and diabetes. It is well known that ingestion of a diet high in saturated fats is one of the major causes of obesity. There are two explanations for this observation. First, diets high in saturated fats do not seem to be as satiating as either high-carbohydrate or highprotein diets (Doucet et al., 1998), even when the high-fat diet is less palatable (Warwick, 1996). Second, whereas increased intake of...

Blindness To Dim Light Is Not The Cause Of Inferior Learning Performance In Aladeficient Rats

As retinal response was also impaired in ALA deficient rats (Fig. 4), one can argue that the decrease in learning ability observed in the brightness-discrimination learning test is the result of retinal dysfunction but not of cognitive dysfunction. However, we interpreted that rats that were n-3 fatty acid deficient could recognize even dim light because its intensity was sufficient to evoke electroretinographic responses (Yamamoto, 1988). Moreover, the R- responses were significantly more than...

PET Imaging of Labeled Fatty Acid Incorporation into the Human Brain

Positron emission tomography (PET) has been used to quantify local glucose metabolism and blood flow in the human brain and to image brain receptor densities (Rapoport, 1995). However, to date, PET has not been employed successfully in humans to image signal transduction beyond the receptor, the downstream process by which neurotransmitters and drugs are closely linked to cognition and behavior (Cooper et al., 1996). In view of our results on dopaminergic and cholinergic signaling in normal and...

Impact Of Dietary Essential Fatty Acids On Neuronal Cell Composition And Function

Brain membranes were generally viewed as resistant to structural change by both endogenous and exogenous factors. Data have shown that brain membranes are much more sensitive to changes in composition induced by dietary fat than previously thought (Bourre et al., 1989a Foot et al., 1982 Jope & Jenden, 1979 Lee, 1985 Wurtman et al., 1981). Moreover, the extent of the changes in brain membrane composition by dietary fat varies among brain regions, cell types, and organelles (reviewed by...

Psychological Stress and the Immune System

Early studies in the field examined the effects of stress on general components of the immune system, such as T-cells and natural-killer (NK) cells. More recent studies chose to measure another component of the immune system the cytokines, a system that is composed of molecules called interleukin. They are a group of naturally occurring proteins that are important in the activation of lymphocytes of the immune system. They were discovered in the 1970s, and several known types of interleukin...

Genetic And Dietary Factors Which Influence N3 Fatty Acid Metabolism

Because of the inability to synthesize n-3 fatty acids de novo, all animals require these fatty acids in their diet to meet their demand for maintaining a high concentration of DHA in the brain. Although little direct evidence exists in any species concerning the quantitative conversion of n-3 fatty acid precursors to DHA, it has been estimated based on rodent studies that an n-3 fatty acid intake of 0.5 of energy as a-linolenic acid (LNA) is needed in order to maintain an adequate level of DHA...

Exercise Training

Few studies have followed the impact of long-term training on the immune systems of elderly people. Given that a number of age-related changes occur in many systems (e.g., neuroendocrine) known to alter immune function both at rest and during exercise, it would be of value to learn the extent to which both acute and chronic exercise influence immune function in the elderly. In older humans, aerobic exercise training lowers the heart rate at rest, reduces levels of the heart rate and plasma...

Influence of Omega3 PUFAs on Body Fluid and Sodium Homeostasis

The above-described homeostatic functions are, in large part, dependent on proper neural functioning and the n-3 PUFAs are crucial to neural function. Receptor-driven processes are also crucial to these homeostatic functions. n-3 PUFAs can influence mechanisms known to be involved in body fluid homeostasis. Vaskonen (1996) showed that supplementation of a high-sodium (6 ) diet with n-3 PUFA-rich fish oil increased the ability of stroke-prone-spontaneously hypertensive rats to excrete sodium and...

Methods of DHA Administration and Dietary Regimen

Docasahexaenoic acid was administered orally either as the ethyl ester or as the triglyceride. The DHA ethyl ester was supplied by the Charleston Laboratory through a grant from the Fish Oil Test Materials Program (NIH ADAMHA DOC). This material is no longer available at this time. The triglyceride preparation is supplied by the Martek Bioscience Corporation, as a product referred to as DHASCO ARASCO. The DHASCO supplies DHA, and the ARASCO provides arachidonic acid. The triglycerides contain...

Fatty Acid Ethyl Esters As Fatty Acid Supplements

There is substantial clinical interest in fatty acid supplements as treatments for a variety of diseases. Oral preparations of FAEEs have been made available for fatty acid supplementation and with the introduction of FAEE capsules for oral intake, there were a number of studies to evaluate ethyl ester absorption from the gastrointestinal (GI) tract. In 1991, Nordoy et al. reported that ethyl esters and triglycerides were equally well absorbed from the GI tract in human subjects (Nordoy, 1991)....

Considerations For Future Intervention Trials

The long history of clinical studies in cardiovascular diseases, infant nutrition, and other illnesses have yielded valuable lessons that can help to form the design of future studies of psychiatric disorders. Baseline measurements are essential, as some subjects may enter the study with high tissue concentrations of EPA and DHA and supplementation may produce little additional effect. Biological markers are the most accurate measure of fatty acid status, but a simple dietary questionnaire may...

Maternofetal Conversion in Primates

The fetal supply of n-3 fatty acids is ultimately from the placenta. The delivery of fatty acids from the maternal circulation to the developing fetus has been reported by others in several studies. Although the human placenta lacks both A-6 and A-5 desaturase activities (Chambaz et al., 1985 Haggarty, Page, Abramovich, Ashton, & Brown, 1997 Innis, 1991), it does preferentially sequester DHA and AA (Ruyle, Connor, Anderson, & Lowensohn, 1990) and assists in concentrating LCP in the fetal...

Essential Fatty Acids

Few topics in nutrition cause so much controversy and concern and are as misunderstood as fat. The dominant message from the medical profession has been to dramatically reduce the amount of fat we eat, in the interest of combating risks associated with cardiovascular disorders, diabetes, and other chronic disorders. At the same time, deficiencies in fat intake are equally likely to contribute to health hazards, including increased risk of infection, dysregulation of chronobiological activity,...

Influence of n3 PUFAs on Acquisition and Distribution of Body Fat Food Intake and Body Weight

Pufa Obesity

Addition of long-chain n-3 PUFAs to the diet significantly reduces body adiposity and increases lean body mass. For example, in a long-term (6 months) study, 3- to 4-mo-old rats were maintained on semisynthetic diets in which the fat content of the diet comprised 45 of the energy. Relative to the rats maintained on a diet containing lard (high in saturated fats) or corn oil, rats maintained on a diet containing n-3-PUFA-rich fish oil had less adipose tissue in epididymal, inguinal, mesenteric,...

The Presence Of Fatty Acid Ethyl Esters In Vitro And In Vivo

The first description of in vitro enzymatic synthesis of fatty acid ethyl esters came from Margolis in 1962 (Margolis, 1962). In experiments with adipose tissue microsomes, he showed that glycerol, ethanol, and several other alcohols form esters with 14C-palmitate when the alcohol is added in millimolar concentration. The esterification of these alcohols required the presence of CoA and ATP or of 14C-palmityl-CoA. Intrigued by this observation, Goodman and Deykin injected rats with...

Dha And Adhesion Molecules

Communication between leukocytes and the rest of the body that they patrol requires the intimate association of cells and, thus, the reciprocal expression of receptor and ligand on the respective cell types. Molecules involved in leukocyte adhesion and costimulation are exemplified by the integrins, CD11a CD18 (LFA-1), CD11b CD18 (Mac-1), CD11c CD18 (CR4), members of the immunoglobulin supergene family, CD54 (ICAM-1), CD4, CD8, CD106 (VCAM-1), and C-type lectins (e.g., CD62E E-selectin )....

Dietary n3 Deficiency in the

Visual Acuity and n-3 Deficiency Perhaps the most consistent effect of n-3 deficiency is found on vision. For instance, when Wistar rats that had been fed sunflower-oil-based chow for three generations were compared to a similar soybean-oil-fed group, there were striking and highly significant differences in their electroretinograms (Bourre, et al., 1989). In 4-wk-old rats, the amplitudes of the a- and b-waves in the LNA-rich group were 39 and 80 higher, respectively, compared to the...

Dietary n3 Deficiency in the Mouse 721 Mouse Visual Acuity and n3 Deficiency

As seen in rats, there is no evidence of a strong correlation between visual acuity and learning in the mouse. The second generation of mice (F1) fed a diet poor in LNA was compared to a group fed laboratory chow. In adult mice, there was a significant difference in the retinal concentration of DHA, but the difference in b-wave electroretinograms ceased to be significant at the seventh week (Carrie, et al., 1999). The ability to learn was examined using the passive-avoidance test and the...

Effect of Dietary Fat on Very Long Chain Fatty Acids and Rhodopsin Content

Retina membrane phospholipids, particularly phosphatidylethanolamine, contain a high level of 22 6n-3 (Birch et al., 1992 Suh et al., 1994). In the rod outer segment of the retina, significant amounts of 22 6n-3 in phosphatidylserine and phosphatidylcholine also occur (Suh et al., 1994). Increased dietary intake of n-3 fatty acids increases the n-3 20 4n-6 ( w w) 22 6n-3 ( w w) 20 4n-6 ( w w) 22 6n-3 ( w w) Fig. 2. Developmental profiles and effect of dietary 20 4n-6 and 22 6n-3 on 20 4n-6 or...

DHA and Membrane Fluidity

It is often erroneously assumed that more fatty acyl double bonds automatically means a more fluid membrane. By differential scanning calorimetry, however, it has been reported that for a series of PCs where the sn-1 chain is stearic acid and the sn-2 chain has zero, one, two, three, four, or six (DHA) double bonds, the phase transition temperature (Tm) decreases upon the addition of a first and second double bond (Coolbear et al., 1983 Dratz & Deese, 1986). However, further double bonds...

Dietary Modulation of Retinal Fatty Acid Composition and Function

The effect of maternal diet on the modulation of n-3 fatty acid in the retina of offspring has been studied in newly hatched chicks (Anderson et al., 1989), juvenile felines (Pawlosky et al., 1997) and piglets (Arbuckle & Innis, 1993). Docosahexaenoic acid appears to be the preferred fatty acid for raising the level of 22 6n-3 in the retina and brain among different sources of n-3 fatty acids (Anderson et al., 1990). Feeding corn oil supplemented with 22 6n-3 is able to restore the 22 6n-3...

Effect Of Dietary n3 Fatty Acids On Cognitive Function

Animal models are useful because greater depletion of DHA is possible than in human studies. Typically, a depleted condition is achieved by feeding several generations of rodents a diet essentially free of n-3 fatty acids. A swifter protocol for experimental n-3 deficiency consists of removing the infant rat from the dam, gastrostomizing it, and feeding it synthetic formula via a pump (Ward, et al., 1996). This leads to over 50 reduction in brain DHA in just 8 wk and as much as 90 reduction in...

Dha And Major Histocompatibility Complex Proteins

Fatty acids are reported to affect the expression of MHC molecules. In some cases, the protein's synthesis may be affected, whereas other experimental designs point to a direct effect of the lipid on plasma membrane-bound MHC. The function of MHC molecules is to bind peptides and present these peptides to specific T-cells, thereby clonally activating T-cells reactive to the peptide. The two key classes of MHC molecules functioning in this fashion are class I (MHC I) and class II (MHC II). MHC I...

Nutrition Intervention

Undernutrition is a common factor underlying many pathological conditions in the elderly and a common symptom in over 50 of hospitalized elderly patients. Macronu-trient and micronutrient deficits are though to be partially responsible for the depressed immune system in the elderly, even in the apparently healthy independent-living elderly (Lesourd, 1999). Protein-energy malnutrition is associated with decreased lymphocyte proliferation, reduced cytokine release, and decreased antibody...

Aging Exercise and Antioxidant Defense System

The oxidant antioxidant balance is an important determinant of immune cell function, including maintaining integrity and functionality of membrane lipids, cellular proteins, nucleic acids, and for control of signal transduction and gene expression in immune cells. Enzymatic and nonenzymatic antioxidants play a vital role in protecting tissues from excessive oxidative damage during exercise. Antioxidant enzymes play an important role in defending the cells against free-radical-mediated oxidative...

Introduction Fatty Acids And Neuronal Excitability

The critical role of fatty acids in nervous system development have been emphasized by multiple authors in this volume and in numerous previous studies (for reviews, see Innis, 1991 Neuringer et al., 1994 Uauy et al., 1996 Kurlak & Stephenson, 1999 Gibson, 1999). Essential fatty acids, especially long-chain polyunsaturated fatty acids (PUFAs), are necessary for development of normal retinal and neuronal membranes (Neuringer, et al., 1988) and subsequent normal behavior and cognition (Enslen,...

Exercise and Immune Function

Aging leads to a diminution of resting immune function, increasing the risk of infection, tumor development, and autoimmune diseases (Shephard and Shek, 1995). The production of IL-2 is decreased, sometimes with a decrease of total T-cell count, and often with changes in T-cell subsets and proliferative responses to mitogens. However, NK cell activity remains unchanged. In theory, moderate exercise training should help to reverse the adverse effects of aging upon the immune system. However,...

Immune Theory of Aging

Original immunologic theory of aging suggests that aging in mammals is a self-destructive process leading to a decline in immune response. The failure in immune homeostasis is associated with a consequent rise in autoimmunity (Walford, 1987). Age-related phenomena such as increased prevalence of autoantibodies and monoclonal immunoglobulins reflect dysregulation of the senescent immune system rather than a simple decline in responsiveness. The age-related changes primarily occur in the...

Possible Implications Of Observations In Rat In Human Behavior

Rudin (1981) described a causal relationship between ALA deficiency and neurotic disorders in humans. Psychoses and neuroses of some pellagra cases unresponsive to multivitamin therapy have been treated effectively with linseed oil enriched with ALA. In 1982, Holman described numbness, paraesthesia, weakness, inability to walk, pain in the legs, and blurring of vision in a 6-yr-old girl under total parenteral nutrition taking safflower oil as the source of essential fatty acid. When the regimen...

PUFA and the Immune System

Repeated demonstrations that PUFA can modify the production and activity of various components of the immune system have left unexplained the mode of action by which it exerts its effects. Several mechanisms had been proposed, including the following membrane fluidity changes that might effect the capability of cytokines to bind to their respective receptors on the cell membrane lipid peroxidation decrease in free-radical-induced tissue damage prostaglandin production an indirect mechanism...

The Immune System and Stress

The immune system is the collection of organs, tissues, and cells responsible for the organism to resist attack by antigens or invasive foreign bodies, particularly microbes. In light of the research of the past few decades, the classic definition and conceptualization of the immune system has changed. The immune system, once considered a closed system (i.e., it reacts only to internal body events), is now recognized to be open and subject to activation by the nervous system. There are...

Applicability To Humans

What are the implications of these studies of n-3 fatty acid deficiency and subsequent repletion in rhesus monkeys to human beings First, these data strongly suggest that any n-3 fatty acid-deficient state will be corrected by fish oil containing EPA and DHA or in other studies, a diet containing n-3 fatty acids from soy oil (18 3n-3 linolenic acid). The brain phospholipids will readily assemble the correct amounts of DHA in the sn-2 position of the phospholipid molecular species. Furthermore,...

EFA Ratio and Stress

Our own study examined the effects of a mixture of fatty acids on cortisol and cholesterol levels in laboratory stress situations. (Yehuda, al el, 2000). A compound of free nonesterified unsaturated fatty acids a-linolenic and linolenic acids in a ratio 1 4 was administered for 3 wk prior to injection of cortisone (10 mg kg) or prior to immersion of rats in a 10 C saline bath. The results confirmed the expected elevation of cortisol and cholesterol level in stress, but, more importantly, the...

DHA n3 C226

Carbon skeleton models of DHA (n-3) and DPA (n-6) noting the position of the methyl terminal double bond at the n-3 and n-6 positions respectively. various animal species (including man) to make DHA. In humans, the conversion rate of LNA to DHA is estimated to be 2.5-4.0 (Gerster, 1998) and that depends on the diet of the individual. In infants, this can even be as low as 1 conversion (Salem, et al., 1996). This means that most humans living on a Western diet will have insufficient in...

Crossnational Epidemiology And Major Depression

The analyses of cross-national epidemiological data, collected using high-quality modern diagnostic and epidemiological sampling methods, does provide one method of testing the hypothesis that a lower omega-3 fatty acid status is related to higher prevalence rates of affective disorders, psychotic disorders, or aggressive behaviors. Economic data describing seafood consumption has been useful in these cross-national studies. Although economic data on the production and consumption of seafood...

Diet And Schizophrenia

Although there have been studies that have shown the importance of dietary essential fatty acids (EFAs) for healthy neurodevelopment (Crawford, 1993), until recently there had been no studies of infant feeding practices in relation to subsequent schizophrenia. It has been shown that the children of women pregnant during the Dutch famine (19441945) were significantly more likely to develop schizophrenia in later life (Susser & Lin, 1992). Although these women suffered multiple dietary...

Body Energy Homeostasis

Brain Gdf15 Cachexia Image Homeostasis

Many factors are involved in the control of food intake. Some of the most important factors controlling the amount of food that we eat include environmental factors such as food availability, the characteristics of the food itself (e.g., smell, taste, our eating habits, learned preferences and aversions) as well as other psychological and social factors, including our lifestyle. Although these psychosocial factors are extremely important to the food intake patterns of humans, this section will...

Ketones And The Ketogenic Diet

The KD was formulated as an epilepsy treatment around 1921 (Wilder, 1921). The diet was designed to simulate the biochemical changes of fasting, which was long recognized as an efficacious, short-term way to reduce seizures in persons with epilepsy (Geyelin, 1921). The diet consists of a high percentage of fat, adequate protein for growth, and minimal carbohydrate, constituted in a ratio of 3-4 g of fat for every gram of combined protein and carbohydrate (hence the notations 3 1 or 4 1 for the...

Dietary Lna And Dha As Substrates For Brain And Retina Dha Compositional Studies

Kliauea Graph

In nontracer experiments, relative contribution of dietary LNA and DHA to CNS DHA accretion have been examined in various species, including chicks, rat pups, newborn piglets, and guinea pigs. Anderson and colleagues studied the relative efficacy of LNA and DHA in restoring neural DHA levels in newly hatched chicks, as presented in Fig. 1 (Anderson, Connor, & Corliss, 1990). Laying hens were fed a n-3-deficient diet for 2 mo, and their hatched chicks were then fed a control diet or...

Cholesterol and Fatty Acids

Cholesterol is involved in many functions of the membrane. It is well established that cholesterol decreases the membrane fluidity index, with consequences on the activity of ion channels, and receptor functions and is involved in dopamine release. Moreover, cholesterol is a key molecule in the end product of the CRF-ACTH axis. Steroids are derivatives of cholesterol and it is, therefore, interesting that various fatty acids have differential effects on cholesterol metabolism. Huang et al....

Attentiondeficit Hyperactivity Disorder

Initial reports of deficiencies of essential fatty acids among children with attention-deficit hyperactivity disorder and dyslexia raised the promise of potential nondrug treatments. Convincing treatment data from interventional trials has not yet been reported. (Stevens et al. (1995) found that 53 subjects with attention-deficit hyperactivity disorder had significantly lower concentrations of AA, EPA, and DHA in plasma polar phospholipids when compared to 43 control subjects. (Stordy 1995) has...

Pufa A Feasible Epilepsy Treatment

The preceding discussion has established the following (1) PUFAs are an important modulator of neuronal excitability (2) dietary PUFA can alter several aspects of brain function (3) the ketogenic diet is an effective therapeutic modality for some persons with epilepsy (4) the mechanism of the ketogenic diet's seizure protective effect is unknown but may involve lipid components (5) the ketogenic diet is composed of a high volume of fats that contain a variable proportion of PUFA. From these...

Effects Of La And Gla Treatment On Diabetic Nerve

The reduced activity of the n-6 fatty acid biosynthetic pathway in the diabetic nerve could decrease the availability of AA for prostanoid formation and this could have deleterious consequences on the nerve vasculature, with resultant adverse effects on nerve function. The depletion of AA could be exacerbated by a heightened level of reactive oxygen species ROS , which react readily with the double bonds of polyunsaturated fatty acids. A number of investigators have examined the effect of...

Fatty Acid Ethyl Esters As Markers Of Ethanol Intake

Fatty Acid Intake America

Because of the long half-life of FAEEs in adipose tissue, it was suggested that FAEE in adipose tissue could be a laboratory marker for previous alcohol intake, particularly for forensic applications where adipose tissue samples can be readily obtained. In postmortem samples from four chronically intoxicated subjects whose blood ethanol levels were zero, it was demonstrated that prior ethanol ingestion could be established by the presence of FAEEs in the adipose tissue Laposata, 1989 . In this...