Ratio Of Essential Fatty Acids Research Articles

Role of nutritional factors at the early life stages in the pathogenesis and clinical course of type 1 diabetes.

Nutrition has been suggested as an important environmental factor other than viruses and chemicals in the pathogenesis of type 1 diabetes (T1D). Whereas various maternal dietary nutritional elements have been suggested and examined in T1D of both humans and experimental animals, the results largely remain controversial. In a series of studies using T1D model nonobese diabetic (NOD) mice, maternal dietary n-6/n-3 essential fatty acid ratio during pregnancy and lactation period, that is, early life stages of the offspring, has been shown to affect pathogenesis of insulitis and strongly prevent overt T1D of the offspring, which is consistent with its preventive effects on other allergic diseases.

Nutrients and non-volatile taste compounds in Chinese mitten crab by-products

Edible viscera (EV) and remainder tissues (RTs) are two by-products of Chinese mitten crab. The objective of this study was to assess the nutrient and non-volatile taste compound contents of EV and RTs. EV and RTs were high in fat (25.35 %) and protein (16.46 %), respectively. Both by-products were good sources of Zn, Fe, and Cu. Both samples contained unsaturated fatty acids (75 % of the total fatty acids) and a balanced ratio of essential fatty acids. The total amino acid content relative to protein in EV and RTs were 77.62 and 66.74 g/100 g, respectively. Alanine (sweet), glutamate (umami), and arginine (bitter/sweet) were the predominant free amino acids that contributed to pleasant flavors due to their taste activity values (TAVs) >1. TAVs of disodium 5′-adenosine monophosphate, disodium 5′-guanosine monophosphate, and disodium 5′-inosine monophosphate were >1 in RT but <1 in EV. Equivalent umami concentrations were 2.71 and 9.00 g MSG/100 g in EV and RTs, respectively, indicating that umami taste in both by-products was very intense. EV and RTs have high nutritional and flavor qualities and could be utilized as flavors and functional food ingredients.

Omega-6/omega-3 essential fatty acid ratio in cultured beluga sturgeon

The balance of omega-6/omega-3 fatty acids is an important factor in human health. High omega-6 fatty acid content in the diet along with a high omega-6/omega-3 ratio can lead to the development of many chronic diseases. Conversely, higher levels of omega-3 fatty acids such as eicosapentaenoic acid (C20:5, EPA) and docosahexaenoic acid (C22:6, DHA) and lower omega-6/omega-3 ratio are desirable for human health. We determined the lipid content in beluga flesh which was 6.5 %. Monounsaturated fatty acids were the main class of fatty acids followed by polyunsaturated and saturated fatty acids. The EPA and DHA contents of cultured beluga flesh were lower than those of other cultured sturgeon species, which may be due to the contents of these fatty acids in the diet. The content of omega-6 fatty acids (25.7 %) was higher than omega-3 fatty acids (8.58 %), giving an omega-6/omega-3 ratio of 3.00.

Isolation and analysis of natural compounds from silkworm pupae and effect of its extracts on alcohol detoxification

AbstractSilkworm pupae have much potential and many applications as a natural medicine to promote human health. However, their chemical components have not been fully characterized or understood. HPLC analysis was conducted to determine the content ratio (%) of individual amino acids in total protein of the pupae. It showed that glutamic acid (18.3%), histidine (14.6%) and alanine (10.2%) are the most common amino acids in silkworm pupae. Fatty acid composition of silkworm pupae oil was revealed by high‐pressure liquid chromatography and gas chromatography – mass spectroscopy analyses. They contain a high ratio of essential fatty acids, [α‐linolenic acid (ω‐3 fatty acid]+ linoleic acid) (49.0%), and also contain non‐essential fatty acids, oleic acid (19.9%), palmitoleic acid (2.5%), palmitic acid (19.7%), stearic acid (8.6%), and eicosapentaenoic acid (EPA) (0.3%). In addition, they also contain antioxidants, quercetin diglucoside and nutritionally important riboflavin (vitamin B2). This study suggests that silkworm pupae are a nutritionally valuable food product and are applicable as cosmetic components with essential amino acids, essential fatty acids, antioxidants and vitamins. The animal experiment showed that alcohol dehydrogenase (ADH) activity was significantly higher in the liver of mice orally administered with 0.5 mg/mL of silkworm extract and alcohol than with commercial Dawn808™ and alcohol, indicating that silkworm pupae extracts have alcohol detoxification activity.

Evolución neurológica, neuropsicológica y oftalmológica tras un año de suplementación con ácido docosahexaenoico en pacientes fenilcetonúricos

INTRODUCTION. Phenylketonuria (PKU) is an autosomal recessive metabolic disease caused by a deficiency of phenylalanine hydroxylase. The dietary therapy for the effective management of PKU, in particular the restriction of high-protein foods of animal-origin, compromises patients' intake of fat and distorts the n-3:n-6 ratio of essential fatty acids in the diet. This deficiency can contribute to neurological and visual impairment. AIM. To evaluate changes in white matter alterations, visual evoked potential (VEP) latencies and performance in executive and motor functions in a group of early and continuously treated PKU patients after supplementation with docosahexaneoic acid (DHA). PATIENTS AND METHODS. We selected 21 PKU patients with early diagnosis (age range: 9-25 years), on a Phe-restricted diet and supplemented with PKU formula. Inclusion criteria were: low erythrocyte DHA values, prolonged P100 wave latencies in VEP and/or presence of white matter hyperintensities on brain magnetic resonance imaging (MRI), and intellectual quotient > 80. All patients were treated with DHA (10 mg/kg/day) for 12 months. Assessment was conducted at baseline and after 12 months of treatment, and included biochemical parameters, brain MRI, VEP, ophthalmologic evaluation and neuropsychological tests. RESULTS AND CONCLUSION. All the patients normalized the DHA levels after supplementation. Improvement in the P100 wave latencies, and fine motor skills was significant. No significant improvement in the other explorations was evident after supplementation. Further investigations seem advisable to establish a cause-effect relationship between DHA treatment and the slight improvement observed in some neurological functions.

Consensus Dietary Guidelines for Healthy Living and Prevention of Obesity, the Metabolic Syndrome, Diabetes, and Related Disorders in Asian Indians

India is undergoing rapid nutritional transition, resulting in excess consumption of calories, saturated fats, trans fatty acids, simple sugars, salt and low intake of fiber. Such dietary transition and a sedentary lifestyle have led to an increase in obesity and diet-related non-communicable diseases (type 2 diabetes mellitus [T2DM], cardiovascular disease [CVD], etc.) predominantly in urban, but also in rural areas. In comparison with the previous guidelines, these consensus dietary guidelines include reduction in the intake of carbohydrates, preferential intake of complex carbohydrates and low glycemic index foods, higher intake of fiber, lower intake of saturated fats, optimal ratio of essential fatty acids, reduction in trans fatty acids, slightly higher protein intake, lower intake of salt, and restricted intake of sugar. While these guidelines are applicable to Asian Indians in any geographical setting, they are particularly applicable to those residing in urban and in semi-urban areas. Proper application of these guidelines will help curb the rising "epidemics" of obesity, the metabolic syndrome, hypertension, T2DM, and CVD in Asian Indians.

Diet with a low n‐6/n‐3 essential fatty acid ratio when started immediately after the onset of overt diabetes prolongs survival of type 1 diabetes model NOD mice

Type 1 diabetes is a multifactorial disease involving genetic and environmental factors and results from the destruction of pancreatic islet β cells, virtually the only source of insulin. When the majority of β cells are lost, a 'honeymoon' period of variable length follows: namely, a fleeting phase of residual endogenous insulin production, during which glycemic control is achieved with modest or no doses of insulin. However, the remaining β cells are eventually lost, causing the individual to become insulin-dependent and to require long-term insulin therapy or islet transplantation. Here we show that NOD mice, a type 1 diabetes model, survived significantly longer when their diet was changed from one chow with a high essential fatty acid (EFA) ratio (n-6/n-3, 14.5) to another with a low n-6/n-3 ratio (3.0) within 6 days after the onset of overt diabetes (i.e. the 'honeymoon' period), than mice that were continuously fed with the chow with the high n-6/n-3 ratio. This effect was not observed when the chow was changed later than 9 days after the onset. Significantly larger number of islets remained with suggestive islet neogenesis from the pancreatic duct and pathological changes in renal glomeruli were significantly milder in NOD mice fed the chow with the low n-6/n-3 ratio within 6 days after the onset of overt diabetes than those continuously fed with the high-n-6/n-3-ratio chow. These findings indicate that a diet with a low n-6/n-3 ratio prolongs the 'honeymoon' period by retaining the β cell mass, suggesting its potential therapeutic merit.

Maternal dietary n‐6/n‐3 fatty acid ratio affects type 1 diabetes development in the offspring of non‐obese diabetic mice

Environment factors, including maternal or infant dietary nutrition have been reported to have an influence on the pathogenesis of type 1 diabetes. In the present study, to investigate the effect of maternal or post-weaning offspring's nutrition, in particular the essential fatty acid ratio (n-6/n-3) on the development of type 1 diabetes, we prepared two kinds of chows with n-6/n-3 ratios of 3.0 (L) and 14.5 (H), and provided them to mothers of non-obese diabetic (NOD) mice during gestation and lactation and to the offspring after weaning. The n-6/n-3 ratios in breast milk and erythrocyte membrane of NOD offspring became nearly the same with that of the maternal diet at 2 weeks after birth. In the L chow-fed offspring from L chow-fed mother (LLL), levels of insulitis were higher than those in the H chow-fed offspring from H chow-fed mother (HHH) at 4 weeks of age, while the levels in the LLL offspring became lower than those in the HHH after 6 weeks. Early insulin autoantibody expressions were found from 2 to 6 weeks in the HHH offspring, but not in the LLL. The LLL offspring exhibited strong suppression of overt diabetes development in regard to the onset and accumulated incidence of diabetes compared to the HHH. The study with combined L and H chows during gestation, lactation in mother and in post-weaning offspring revealed that only the LLH chow significantly suppressed the development of diabetes with similar kinetics to LLL chow, although the other combinations may delay the onset of diabetes. The present findings suggest that n-6/n-3 ratio of the maternal diet during gestation and lactation rather than that of offspring after weaning strongly affects the development of overt diabetes in NOD mice.

Improvement of Oil Quality in Soybean [Glycine max (L.) Merrill] by Mutation Breeding

AbstractLow oxidative stability, off‐flavor and rancidity are the major drawbacks of soybean oil. Modification of the fatty acid composition of soybean [Glycine max (L.) Merrill] oil can improve its quality and value for processors and acceptability among consumers. Mutation breeding of soybean was therefore initiated with the objective of identifying stable soybean mutants with altered fatty acid composition for improved oxidative stability and nutritional quality. Seeds of soybean cultivar ‘MACS 450’ were treated with γ‐radiation and/or ethyl methane sulfonate (EMS). The harvest of M1 plants was evaluated for fatty acid composition by gas chromatography. Highly significant variation in all the fatty acids except palmitic acid was observed. Treatment of EMS in higher concentrations as well as combined treatment of both the mutagens, i.e., γ‐radiation and EMS were effective in increasing the variability for the fatty acid content in soybean oil. The variability was skewed towards high levels of oleic (35–42%) and low levels of linolenic acid (3.77–5.00%). M3 and M4 generations of desirable variants were analyzed for the stability of the mutated trait. Only high oleic variants were stable in M3 and M4 generations. Based on fatty acid values, oxidative stability index (OSI), nutritional quality index (NQI) and ratio of essential fatty acids (ω6/ω3) were calculated for the control and M2, M3 and M4 generations. The ω6/ω3 ratio in all the high oleic mutants was within the World Health Organization (WHO) recommended value (5–10%). A significant positive correlation between OSI and oleic acid content (P &lt; 0.001) indicated improved oxidative stability of the oil while retaining nutritional quality. These high oleic lines could be utilized further in breeding programs for improvement of soybean oil quality.

Egg production and hatching success in the calanoid copepods Calanus helgolandicus and Calanus finmarchicus in the North Sea from March to September 2001

Spatial and seasonal egg production rates (E r ) and egg hatching success in the copepods Calanus finmarchicus and Calanus helgolandicus were measured in the North Sea from March to September. Food availability was monitored by chlorophyll and protist concentrations and three size fractions of seston fatty acids. Seasonal and spatial distribution and production differed between the species. Calanus finmarchicus was found only offshore of the 50-m isobath, with decreasing E r (37-28 eggs female- day -1 ) from March to July. Calanus helgolandicus had two abundance peaks, in spring and autumn, with a low in May during which time the highest E r were observed (38 eggs female- day -1 ). At other times, E r in C. helgolandicus remained lower than in C. finmarchicus (∼20 eggs female -1 day -1 ). Normalized E r (E n ) in both C. finmarchicus and C. helgolandicus were positively related to ciliate biomass while only negative relationships were found for all other variables measured. Hatching success in both Calanus species combined was significantly correlated with the essential fatty acid ratio 22:6n3/20:5n3.

Omega-6/Omega-3 Essential Fatty Acid Ratio and Chronic Diseases

Several sources of information suggest that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids (EFA) of ∼1 whereas in Western diets the ratio is 15/1–16.7/1. Western diets are deficient in omega-3 fatty acids, and have excessive amounts of omega-6 fatty acids compared with the diet on which human beings evolved and their genetic patterns were established. Excessive amounts of omega-6 polyunsaturated fatty acids (PUFA) and a very high omega-6/omega-3 ratio, as is found in today's Western diets, promote the pathogenesis of many diseases, including cardiovascular disease, cancer, and inflammatory and autoimmune diseases, whereas increased levels of omega-3 PUFA (a lower omega-6/omega-3 ratio), exert suppressive effects. In the secondary prevention of cardiovascular disease, a ratio of 4/1 was associated with a 70% decrease in total mortality. A ratio of 2.5/1 reduced rectal cell proliferation in patients with colorectal cancer, whereas a ratio of 4/1 with the same amount of omega-3 PUFA had no effect. The lower omega-6/omega-3 ratio in women with breast cancer was associated with decreased risk. A ratio of 2-3/1 suppressed inflammation in patients with rheumatoid arthritis, and a ratio of 5/1 had a beneficial effect on patients with asthma, whereas a ratio of 10/1 had adverse consequences. These studies indicate that the optimal ratio may vary with the disease under consideration. This is consistent with the fact that chronic diseases are multigenic and multifactorial. Therefore, it is quite possible that the therapeutic dose of omega-3 fatty acids will depend on the degree of severity of disease resulting from the genetic predisposition. A lower ratio of omega-6/omega-3 fatty acids is more desirable in reducing the risk of many of the chronic diseases of high prevalence in Western societies, as well as in the developing countries, that are being exported to the rest of the world

Meta-analysis of dietary essential fatty acids and long-chain polyunsaturated fatty acids as they relate to visual resolution acuity in healthy preterm infants.

To derive combined estimates of visual resolution acuity differences between healthy preterm infants consuming different compositions and ratios of essential fatty acids (EFAs) and docosahexaenoic acid (DHA), an omega-3 (n-3) long-chain polyunsaturated fatty acid (LCPUFA). Electronic biomedical reference database (Medline and Health Star from 1965 to July 1999) searches with index terms omega-3, n-3, infant, vision, acuity, and human. Current review article, monograph, and book chapter bibliography/reference section hand searches. A total of 5 original articles and 4 review chapters were reviewed for details on study design, conduct, and outcome. Four prospective trials of EFA/LCPUFA supplementation were included in these analyses. For behaviorally based outcomes, there were 2 randomized comparisons each at </=1, 2, 6, 9, and 12 months of corrected age and 4 randomized comparisons at 4 months of corrected age. For electrophysiologically based outcomes (visual-evoked potential), there were 2 randomized comparisons each at </=1 and approximately 4 months of corrected age. Dietary composition and EFA/LCPUFA balance, study design, and analytic characteristics (duration of feeding, source of EFAs/LCPUFAs, number of subjects in study population, number of subjects analyzed, and basis for estimating age), and experiment-based characteristics (location, number or sites, design, vision tests employed, testing protocol, and ophthalmic examination) were recorded independently by 2 researchers with a standardized protocol. The relative difference in visual resolution acuity between groups of infants who received a source of dietary EFAs/LCPUFAs and groups who did not was computed and then analyzed with the DerSimonian and Laird random-effects method. Analysis of the randomized comparisons (DHA-supplemented formula vs DHA-free formula) showed significant differences in visual resolution acuity at 2 and 4 months of age. Combined estimates of behaviorally based visual resolution acuity differences at these ages were.47 +/-.14 octaves and.28 +/-.08 octaves, respectively. A 1-octave difference is a reduction in the width of the stimulus elements by 50%. These results support efficacy of n-3 LCPUFA intake in early visual system development, although supplementation safety issues still must be addressed through larger randomized trials. Whether n-3 intake confers lasting advantage in visually based process development across the life-span is still to be determined.

The metabolism and n-6/n-3 ratio of essential fatty acids in rats: effect of dietary arachidonic acid and a mixture of sesame lignans (sesamin and episesamin).

In this study, we examined the effect of dietary arachidonic acid (AA) and sesame lignans on the content and n-6/n-3 ratio of polyunsaturated fatty acid (PUFA) in rat liver and the concentrations of triglyceride (TG) and ketone bodies in serum. For 4 wk, rats were fed two types of dietary oils: (i) the control oil diet groups (CO and COS): soybean oil/perilla oil = 5:1, and (ii) the AA-rich oil group (AO and AOS): AA ethyl esters/palm oil/perilla oil = 2:2:1, with (COS and AOS) or without (CO and AO) 0.5% (w/w) of sesame lignans. Dietary AA and sesame lignans significantly affected hepatic PUFA metabolism. AA content and n-6/n-3 ratio in the liver were significantly increased in the AO group, despite the dietary total of n-6 PUFA being the same in all groups, while AOS diet reduced AA content and n-6/n-3 ratio to a level similar to the CO and COS groups. These results suggest that (i) dietary AA considerably affects the hepatic profile and n-6/n-3 ratio of PUFA, and (ii) dietary sesame lignans reduce AA content and n-6/n-3 ratio in the liver. In the AO group, the concentration of acetoacetate was significantly increased, but the ratio of beta-hydroxybutyrate/acetoacetate was decreased. On the other hand, the AO diet increased the concentration of TG in serum by almost twofold as compared to other groups. However, the AOS diet significantly reduced serum TG level as compared to the AO group. In addition, the AOS diet significantly increased the acetoacetate level, but reduced the beta-hydroxybutyrate/acetoacetate ratio. These results suggest that dietary sesame lignans promote ketogenesis and reduce PUFA esterification into TG. This study resulted in two findings: (i) sesame lignans inhibited extreme changes of the n-6/n-3 ratio by reducing hepatic PUFA content, and (ii) the reduction of hepatic PUFA content may have occurred because of the effects of sesame lignans on PUFA degradation (oxidation) and esterification.

Interaction of sesamin and eicosapentaenoic acid against delta 5 desaturation and n-6/n-3 ratio of essential fatty acids in rat.

Sesamin is a specific inhibitor of delta 5 desaturation, the conversion from dihomo-gamma-linolenic acid (20:3, n-6) to arachidonic acid (AA, 20:4, n-6). Previously, we reported that sesamin inhibited delta 5 desaturation of n-6 fatty acids in rat hepatocytes but not that of n-3 fatty acids, from 20:4 (n-3) to eicosapentaenoic acid (EPA, 20:5, n-3). In this study, we investigated the interaction of sesamin and EPA on delta 5 desaturation of both series and the n-6/n-3 fatty acids ratio by measuring actural fatty acid contents in vivo. Rats were fed three types of dietary oils; 1) linoleic acid (LA, 18:2, n-6): linolenic acid (LLA, 18:3, n-3) = 3:1, n-6/n-3 ratio of 3:1 (LA group), 2) LA:LLA = 1:3, n-6/n-3 ratio of 1:3 (LLA group), 3) LA:LLA:EPA = 1:0.5:3, n-6/n-3 ratio of 1:3.5 (EPA group) with or without sesamin (0.5% w/w) for 4 weeks. In all groups, sesamin administration increased the content of dihomo-gamma-linolenic acid (20:3, n-6) in the liver and decreased the delta 5 desaturation index of n-6 fatty acid, the ratio of 20:4/20:3 (n-6). On the contrary, the delta 5 desaturation index of n-3 fatty acid, the ratio of 20:5 + 22:5 + 22:6/20:4 (n-3), was increased by the administration of sesamin. These results suggest that sesamin inhibits the delta 5 desaturation of n-6 fatty acid, but not that of n-3 fatty acid in rat livers. Sesamin administration decreased incorporation of EPA (n-3) and simultaneously increased the AA (n-6) content in the liver. The n-6/n-3 ratio in the liver was increased by administering sesamin under n-3 rich conditions, i.e., the LLA and EPA groups.

Dietary modulation of the immunocompetent system and nonspecific resistance in rats by different ratios of essential fatty acids

Dietary modulation of the immunocompetent system and nonspecific resistance in rats by different ratios of essential fatty acids

The effects of petroleum hydrocarbons on lipid metabolism and energetics of larval development and metamorphosis in the american lobster (homarus americanus Milne Edwards)

Abstract In studies with larval stages of the American lobster ( Homarus americanus ) exposed to a sublethal concentration of South Louisiana crude oil, the normal patterns of lipid storage, utilization and synthesis during larval development and metamorphosis were altered with oil exposure. Increased rates of protein catabolism, delayed molting and reduced growth were also evident among oil-exposed lobster larvae and suggest either deficiency or immobilization of lipid reserves. From analyses of lipid class composition of control and oil-exposed lobster larvae, it is evident that oil-exposed larvae have consistently lower levels of triacylglycerols (the major energy store) and higher levels of sterols than control larvae. Decreased ratios of non-essential fatty acids (both saturated and unsaturated) and increased ratios of essential fatty acids were detected in the neutral lipid pools of oil-exposed larvae that suggest both decreased storage of fatty acids in energy reserves and decreased mobilization of essential fatty acids into phospholipid pools. The fatty acid distribution in the phospholipid pools of oil-exposed larvae, however, varied little from control values and reflects a tendency to preserve the integrity of these structural lipids. Increases in sterol levels may be related to decreased mobilization of cholesterol or other sterols and/or transformation of cholesterol into metabolic pathways including the biosynthesis of ecdysterone. Oil-exposed animals contained trace quantities of benzene, thiophene, toluene, alkylcyclohexane and alkylbenzenes, detected with GC-MS analyses. No naphthalene, dimethylnaphthalene, higher molecular weight aromatics or their phenolic derivatives were detected; their absence may be related to either the detection limits of the methodology used or extremely rapid metabolism and turnover of these components. Alterations in lipid metabolism may account for the developmental and energetic abnormalities observed in marine crustaceans. It cannot be ruled out, however, that decreased lipid utilization, synthesis and mobilization may be a defense mechanism against incorporating lipophilic components of petroleum hydrocarbons in metabolic pathways, and that disruption in energetics and development is a consequence of the reduction in energy available for growth and molting.