The present work explores the effect of dietary omega-3 polyunsaturated fatty acids (PUFAs) intake on lipid peroxidation among mild cognitive impairment (MCI) patients. The plasma lipid hydroperoxide (LPO) levels in 67 MCI patients were compared to those of 134 healthy elderly controls. Omega-3 PUFA intake was assessed using an interviewer-administered food frequency questionnaire. Apolipoprotein E genotyping was performed using polymerase chain reaction and restriction enzyme digestion. The association between various confounders and lipid peroxidation was evaluated using regression analysis. The influence of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake on LPO level was investigated. The results revealed that LPO levels were significantly higher in the MCI group than in the control group. Inverse correlations were found between DHA and EPA intake and LPO level among the MCI group. LPO levels decreased significantly with increasing DHA and EPA intake. In summary, the findings revealed that DHA and EPA can play a role in alleviating oxidative stress and reducing the risk of neurodegenerative diseases.
Total lipids were extracted from 22 species of Malaysian fish and the constituent fatty acids were analysed by gas chromatography. Malaysian fish generally contained high levels of saturated fatty acids (range 36-55% total fatty acids) and contained variable amounts of monounsaturates, chiefly palmitic and stearic acids, but only trace levels of 20:1 and 22:1. Unlike fish caught in colder northern hemisphere waters, Malaysian fish were found to contain arachidonic acid (20:4 omega 6, range 2-12%) in addition to the expected eicosapentaenoic acid (20:5 omega 3, range 1-13%) and docosahexaenoic acid (22:6 omega 3, range 6.6-40.4%).
Omega-3 fatty acid nutrition is widely recognised as essential to health and general well-being. However, health professionals and the general public in Malaysia may lack knowledge on the sources or the amounts of these essential fat components in foods. This paper attempts to correct this scenario by identifying the potential sources of omega-3 fatty acids [a-linolenic acid (ALA), or eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA)] in the Malaysian diet and calculating the amounts of these “nutrients†provided per serving of a wide variety of foods. The information generated provides Malaysian health professionals and consumers with options in food choices or meal planning with the goal towards achieving the recommended nutrient intakes for omega-3 fatty acids. The findings in the present study revealed that the potential sources of omega-3 fatty acids in the Malaysian diet in decreasing order are: edible oils (ALA), fish and fish products (EPA+DHA), vegetables (ALA), meat and eggs (EPA+DHA), and milk/milk products (EPA+DHA). Edible oils which are exceptionally high in ALA such as flaxseed oil and perilla oil are presently unavailable at local retail outlets and supermarkets. However, consumers can still meet the recommended nutrient intakes (RNIs) for omega-3 fatty acids of 0.3 to 1.2% energy (equivalent to 0.67g-2.67g) by choosing a wellbalanced diet prepared preferably with a cooking oil blend containing ALA, and one or more servings daily from at least three of the following food groups: (i) fish (“jelawatâ€, “siakapâ€, sardines, tuna, mackerel, salmon)/seafoods (shrimps, crab)/meat, (ii) vegetables/soybean/ soybean-based products/beans and peas, (iii) omega-3 enriched/fortified foods (eg. “omega-3 eggsâ€), and (iv) ready-to-drink omega-3 milk preparations/soybean milk.
This paper reviews available reports on the omega-6 (linoleic acid, LA) and omega-3 fatty acid
[alpha-linolenic acid (ALA) + eicosapentaenoic acid (EPA) + docosahexaenoic acid) intakes amongst Malaysians against Malaysian Recommended Nutrient Intakes (RNI), focussing particularly on pregnant and lactating women because of the availability of data for these latter vulnerable groups. Overall, the omega-6 and omega-3 fatty acid nutrition amongst Malaysians are poor and far from desirable. The nutritional situation regarding these long-chain polyunsaturated fatty acids
(LCPUFA) amongst Malaysian pregnant and lactating women is alarming and warrants urgent attention in nutrition promotion activities/counselling. Daily consumption of LA by these women and other Malaysians studied ranged from 3.69 - 5.61 % kcal with 38-60% of individuals not meeting their RNIs. Daily intakes of omega-3 fatty acids faired worse, averaging 0.21- 0.33 % kcal with as high as 92% of subjects in one study not meeting their RNIs. The omega-6 to omega-3 fatty acid
ratios obtained in the studies reviewed are about 20:1, which is way above the World Health Organisationrecommended ratio of 5-10:1. Dietary sources of these omega- fatty acids in the subjects studied are chicken, fish and milk. Since local foods are not particularly rich in LCPUFA such as EPA and DHA, the options to improve EPA/DHA nutrition amongst Malaysians are
the greater consumption of omega-3 enriched foods and in the case of pregnant and lactating women, LCPUFA supplementation may warrant serious consideration.
Proximate content, fatty acid and mineral compositions were determined for the ten species of deepsea fish from Southern Java Ocean and Western Sumatra Ocean, Indonesia. The proximate composition was found to be 23.0-24.8 % protein, 1.9-4.1% fat , 0-1.75 % carbohydrate, 1.7-2.4 % ash and 70.1-72.1% water, whereas the fatty acid compositions consisted of 0.86 - 49.63 % saturated fatty acids (SFA), 0.29 - 50.09 % monounsaturated fatty acid (MUFA) and 2.85 % - 46.32 % polyunsaturated fatty acids (PUFAs). Among them, those occurring in the highest proportions were myristic acid (C14:0, 0.12-7.59%), palmitic acid (C16:0, 0.02–20.5%), stearic acid (C18:0, 0.42–49.19), oleic acid (C18:1, 0.29–50.09 %), linoleic acid (C18:2, 0.23– 44.91%), eicosapentaenoic acid (EPA, C20:5n3, 0.41– 4.61%) docosahexaenoic acid (DHA, C22:6n3, 0.28– 3.44%). The rest of the microelements, Cd, Hg, and Pb were all present in amounts below toxic levels.
This study was conducted to investigate and compare the fatty acids and tocopherols of lipid extracted from marine microalgae, Nannochloropsis oculata (NO) and Tetraselmis suecica (TS) using solvent extraction and supercritical fluid extraction (SFE). Fatty acids and tocopherols were determined in the extracted lipid as functions of the temperature (40, 80oC) and pressure (3000, 5000, 7000, 9000psi). Dichloromethane/methanol and hexane were the chosen conventional solvent for fatty acids and tocopherols extraction respectively. The results obtained showed that there were differences in the fatty acid composition of various lipid extracts of NO and TS. Extracts of NO were high in myristic acid (C14:0) (17-35%), palmitic acid (C16:0) (14-47%) and palmitoleic acid (C16:1) (11-42%) whereas extracts of TS were high in C14:0 (21-34%) and C16:0 (29-49%). Eicosapentaenoic acid (EPA) was detected only under certain SFE conditions in NO but was not detected in TS. α-, β- and γ-tocopherol were detected in various SFE extracts of NO but only α- and β-tocopherol were detected in TS. Hexane extraction of both NO and TS resulted in the detection of only α-tocopherol. In conclusion, the use of different extraction methods resulted in different compositions and concentrations of fatty acids and tocopherols in the microalgae studied.
Endothelial cells (ECs) play a role in the optimal function of blood vessels. When endothelial function becomes dysregulated, the risk of developing atherosclerosis increases. Specifically, upregulation of adhesion molecule expression on ECs promotes the movement of leukocytes, particularly monocytes, into the vessel wall. Here, monocytes differentiate into macrophages and may become foam cells, contributing to the initiation and progression of an atherosclerotic plaque. The ability of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) to influence the expression of adhesion molecules by ECs and to modulate leukocyte-endothelial adhesion has been studied in cell culture using various types of ECs, in animal feeding studies and in human trials; the latter have tended to evaluate soluble forms of adhesion molecules that circulate in the bloodstream. These studies indicate that n-3 PUFAs (both eicosapentaenoic acid and docosahexaenoic acid) can decrease the expression of key adhesion molecules, such as vascular cell adhesion molecule 1, by ECs and that this results in decreased adhesive interactions between leukocytes and ECs. These findings suggest that n-3 PUFAs may lower leukocyte infiltration into the vascular wall, which could contribute to reduced atherosclerosis and lowered risk of cardiovascular disease.
The endogenous production of long-chain polyunsaturated fatty acids (LC-PUFA) in carnivorous teleost species inhabiting freshwater environments is poorly understood. Although a predatory lifestyle could potentially supply sufficient LC-PUFA to satisfy the requirements of these species, the nutrient-poor characteristics of the freshwater food web could impede this advantage. In this study, we report the cloning and functional characterisation of an elongase enzyme in the LC-PUFA biosynthesis pathway from striped snakehead (Channa striata), which is a strict freshwater piscivore that shows high deposition of LC-PUFA in its flesh. We also functionally characterised a previously isolated fatty acyl desaturase cDNA from this species. Results showed that the striped snakehead desaturase is capable of Δ4 and Δ5 desaturation activities, while the elongase showed the characteristics of Elovl5 elongases. Collectively, these findings reveal that striped snakehead exhibits the genetic resources to synthesise docosahexaenoic acid (DHA; 22:6n-3) from eicosapentaenoic acid (EPA; 20:5n-3). Both genes are expressed at considerable levels in the brain and the liver. In liver, both genes were up-regulated by dietary C18 PUFA, although this increase did not correspond to a significant rise in the deposition of muscle LC-PUFA. Brain tissue of fish fed with plant oil diets showed higher expression of fads2 gene compared to fish fed with fish oil-based diet, which could ensure DHA levels remain constant under limited dietary DHA intake. This suggests the importance of DHA production from EPA via the ∆4 desaturation step in order to maintain an optimal reserve of DHA in the neuronal tissues of carnivores.
The Fish oils and Aspirin in Vascular access OUtcomes in REnal Disease (FAVOURED) trial investigated whether 3 months of omega-3 polyunsaturated fatty acids, either alone or in combination with aspirin, will effectively reduce primary access failure of de novo arteriovenous fistulae. This report presents the baseline characteristics of all study participants, examines whether study protocol amendments successfully increased recruitment of a broader and more representative haemodialysis cohort, including patients already receiving aspirin, and contrasts Malaysian participants with those from Australia, New Zealand and the United Kingdom (UK).
The FAVOURED study is an international multicentre, double-blind, placebo-controlled trial which commenced recruitment in 2008 and examines whether omega-3 polyunsaturated fatty acids (omega-3 PUFAs) either alone or in combination with aspirin will effectively reduce primary access failure of de novo arteriovenous fistulae (AVF) in patients with stage 4 and 5 chronic kidney disease. Publication of new evidence derived from additional studies of clopidogrel and a high screen failure rate due to prevalent aspirin usage prompted an updated trial design.