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Nutrients Jan 2022The retina requires docosahexaenoic acid (DHA) for optimal function. Alpha-linolenic acid (ALA) and DHA are dietary sources of retinal DHA. This research investigated...
The retina requires docosahexaenoic acid (DHA) for optimal function. Alpha-linolenic acid (ALA) and DHA are dietary sources of retinal DHA. This research investigated optimizing retinal DHA using dietary ALA. Previous research identified 19% DHA in retinal phospholipids was associated with optimal retinal function in guinea pigs. Pregnant guinea pigs were fed dietary ALA from 2.8% to 17.3% of diet fatty acids, at a constant level of linoleic acid (LA) of 18% for the last one third of gestation and retinal DHA levels were assessed in 3-week-old offspring maintained on the same diets as their mothers. Retinal DHA increased in a linear fashion with the maximum on the diet with LA:ALA of 1:1. Feeding diets with LA:ALA of 1:1 during pregnancy and assessing retinal DHA in 3-week-old offspring was associated with optimized retinal DHA levels. We speculate that the current intakes of ALA in human diets, especially in relation to LA intakes, are inadequate to support high DHA levels in the retina.
Topics: Animal Nutritional Physiological Phenomena; Animals; Animals, Newborn; Diet; Dietary Fats; Docosahexaenoic Acids; Female; Guinea Pigs; Linoleic Acid; Maternal Nutritional Physiological Phenomena; Phospholipids; Pregnancy; Retina; alpha-Linolenic Acid
PubMed: 35057481
DOI: 10.3390/nu14020301 -
The Journal of Pharmacy and Pharmacology Aug 2017To review the competence of Omega-3 fatty acids in restricting the progression, thereby leading to prevention of diabetic retinopathy. (Review)
Review
OBJECTIVES
To review the competence of Omega-3 fatty acids in restricting the progression, thereby leading to prevention of diabetic retinopathy.
KEY FINDINGS
Owing to their anti-inflammatory and anti-angiogenic properties, Omega-3 fatty acids alleviate major aetiological agents. These fatty acids are renowned for their beneficial effects in various cardiovascular and other disorders; however, their potential to prevent the progression of diabetic retinopathy remains least explored.
SUMMARY
Utilizing this potential, we may develop effective prophylactic agents which markedly inhibit the advent of retinal angiogenesis and prevent the apoptosis of retinal endothelial and neuronal cells, thereby averting retinal degeneration, hence safeguarding diabetic patients from this sight-threatening complication.
Topics: Animals; Diabetes Mellitus; Diabetic Retinopathy; Docosahexaenoic Acids; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Humans; Neovascularization, Pathologic; Oxidative Stress; alpha-Linolenic Acid
PubMed: 28481011
DOI: 10.1111/jphp.12744 -
International Journal of Food Sciences... May 2021Consumption of omega-3 fatty acids, including the precursor α-linolenic acid (ALA) is often sub-optimal and not in line with international guidelines. Supplementation...
Consumption of omega-3 fatty acids, including the precursor α-linolenic acid (ALA) is often sub-optimal and not in line with international guidelines. Supplementation is debatable, but some individuals, e.g., pre-diabetic, low-grade inflammation, cardiometabolic yet otherwise healthy subjects, might benefit from supra-physiological omega-3 intake, particularly to lessen inflammation. We explored the feasibility of a large clinical trial by performing a pilot study to evaluate adherence, palatability, and self-reported side effects of ALA administration in a group of volunteers. We enrolled 12 individuals with borderline dyslipidemia or overweight, treated with dietary advice according to international guidelines and who had insufficient intakes of essential fatty acids. Subjects were followed for nutritional counselling and were matched with appropriate controls. Patients were administered 6 g/day of ALA, for two months. We report the absence of side effects. such as fishy aftertaste and gastrointestinal distress, in addition to a slight decrease of C-reactive protein concentrations (Identifier: ISRCTN13118704).
Topics: Adult; Aged; Blood Pressure; C-Reactive Protein; Diet; Dietary Supplements; Fatty Acids, Essential; Feasibility Studies; Female; Heart; Humans; Inflammation; Male; Middle Aged; Overweight; Patient Compliance; Pilot Projects; alpha-Linolenic Acid
PubMed: 32746658
DOI: 10.1080/09637486.2020.1802581 -
Journal of Oleo Science Nov 2021Physicochemical properties and chemical composition of Chinese perilla seed oil has been characterized in this study. The result showed that both the cold press oil and...
Physicochemical properties and chemical composition of Chinese perilla seed oil has been characterized in this study. The result showed that both the cold press oil and the solvent extracted oil possessed low acid value and peroxide value. The fatty acid composition result showed that the oil has high content of linolenic acid (C18:3) up to 66.4 g/100 g, followed by linoleic acid (C18:2) of 15.3 g/100 g. The total triacylglycerol (TAG) profiles results showed that the oil contained 20 TAGs including 17 regioisomers, including LnLnLn (35.8 g/100 g), LLnLn (20.2 g/100 g), LLLn (17.7 g/100 g) and PLnLn (14.9 g/100 g) (Ln, linolenic acid; L, linoleic acid; P, palmitic acid). With content of only 0.57 g/100 g oil, the unsaponifiable matters were mainly composed of phytosterols, squalene, tocopherol, alcohols and hydrocarbons. The total phytosterols content was 0.39 g/100 g oil, in which β-sitosterol has high content of 0.31 g/100 g oil.
Topics: Alcohols; Antioxidants; Chemical Phenomena; Hydrocarbons; Isomerism; Linoleic Acid; Liquid-Liquid Extraction; Palmitic Acid; Perilla frutescens; Phytosterols; Plant Oils; Squalene; Tocopherols; Triglycerides; alpha-Linolenic Acid
PubMed: 34645745
DOI: 10.5650/jos.ess21076 -
Experimental Biology and Medicine... Apr 2023Hyperexcitability is a major mechanism implicated in several neuropsychiatric disorders, such as organophosphate-induced status epilepticus (SE), primary epilepsy,...
Hyperexcitability is a major mechanism implicated in several neuropsychiatric disorders, such as organophosphate-induced status epilepticus (SE), primary epilepsy, stroke, spinal cord injury, traumatic brain injury, schizophrenia, and autism spectrum disorders. Underlying mechanisms are diverse, but a functional impairment and loss of GABAergic inhibitory neurons are common features in many of these disorders. While novel therapies abound to correct for the loss of GABAergic inhibitory neurons, it has been difficult at best to improve the activities of daily living for the majority of patients. Alpha-linolenic acid (ALA) is an essential omega-3 polyunsaturated fatty acid found in plants. ALA exerts pleiotropic effects in the brain that attenuate injury in chronic and acute brain disease models. However, the effect of ALA on GABAergic neurotransmission in hyperexcitable brain regions involved in neuropsychiatric disorders, such as the basolateral amygdala (BLA) and CA1 subfield of the hippocampus, is unknown. Administration of a single dose of ALA (1500 nmol/kg) subcutaneously increased the charge transfer of inhibitory postsynaptic potential currents mediated by GABA receptors in pyramidal neurons by 52% in the BLA and by 92% in the CA1 compared to vehicle animals a day later. Similar results were obtained in pyramidal neurons from the BLA and CA1 when ALA was bath-applied in slices from naïve animals. Importantly, pretreatment with the high-affinity, selective TrkB inhibitor, k252, completely abolished the ALA-induced increase in GABAergic neurotransmission in the BLA and CA1, suggesting a brain-derived neurotrophic factor (BDNF)-mediated mechanism. Addition of mature BDNF (20 ng/mL) significantly increased GABA receptor inhibitory activity in the BLA and CA1 pyramidal neurons similar to the results obtained with ALA. ALA may be an effective treatment for neuropsychiatric disorders where hyperexcitability is a major feature.
Topics: Rats; Humans; Animals; Basolateral Nuclear Complex; alpha-Linolenic Acid; Brain-Derived Neurotrophic Factor; Rats, Sprague-Dawley; Activities of Daily Living; Synaptic Transmission; Receptors, GABA-A
PubMed: 37208920
DOI: 10.1177/15353702231165010 -
Frontiers in Public Health 2022This study aimed to investigate the association of α-linolenic acid (ALA; 18:3 ω-3) dietary intake with very short sleep duration (<5 h) in adults based on the CDC's...
OBJECTIVES
This study aimed to investigate the association of α-linolenic acid (ALA; 18:3 ω-3) dietary intake with very short sleep duration (<5 h) in adults based on the CDC's National Health and Nutrition Examination Survey data.
METHODS
Multinomial logistic regression was used to explore the association of ALA intake with very short sleep. To make the estimation more robust, bootstrap methods of 1,000 replications were performed. Rolling window method was used to investigate the trend of the odds ratios of very short sleep with age. A Kruskal-Wallis test was applied to estimate the differences in the ORs of very short sleep between genders and different age groups.
RESULTS
Compared with the first tertile, the ORs of very short sleep and the corresponding 95% CIs for the second and the third tertile of dietary ALA intake in males were 0.618 (0.612, 0.624) and 0.544 (0.538, 0.551), respectively, and in females were 0.575 (0.612, 0.624) and 0.432 (0.427, 0.437). In most cases, the differences between different ages were more significant than those between different sexes. Men's very short sleep odds ratios for the second tertile of ALA intake increased linearly with age before 60.
CONCLUSIONS
The risk of a very short sleep duration was negatively related to the dietary intake of ALA. The effect of ALA on very short sleep is significantly different among groups of different genders and ages.
Topics: Adult; Diet; Eating; Female; Humans; Male; Nutrition Surveys; Sleep; alpha-Linolenic Acid
PubMed: 36062128
DOI: 10.3389/fpubh.2022.986424 -
Frontiers in Immunology 2022Immune function changes across the life course; the fetal immune system is characterised by tolerance while that of seniors is less able to respond effectively to...
INTRODUCTION
Immune function changes across the life course; the fetal immune system is characterised by tolerance while that of seniors is less able to respond effectively to antigens and is more pro-inflammatory than in younger adults. Lipids are involved centrally in immune function but there is limited information about how T cell lipid metabolism changes during the life course.
METHODS AND RESULTS
We investigated whether life stage alters fatty acid composition, lipid droplet content and α-linolenic acid (18:3ω-3) metabolism in human fetal CD3 T lymphocytes and in CD3 T lymphocytes from adults (median 41 years) and seniors (median 70 years). Quiescent fetal T cells had higher saturated (SFA), monounsaturated fatty acid (MUFA), and ω-6 polyunsaturated fatty acid (PUFA) contents than adults or seniors. Activation-induced changes in fatty acid composition differed between life stages. The principal metabolic fates of [C]18:3ω-3 were constitutive hydroxyoctadecatrienoic acid synthesis and β-oxidation and carbon recycling into SFA and MUFA. These processes declined progressively across the life course. Longer chain ω-3 PUFA synthesis was a relatively minor metabolic fate of 18:3ω-3 at all life stages. Fetal and adult T lymphocytes had similar lipid droplet contents, which were lower than in T cells from seniors. Variation in the lipid droplet content of adult T cells accounted for 62% of the variation in mitogen-induced CD69 expression, but there was no significant relationship in fetal cells or lymphocytes from seniors.
DISCUSSION
Together these findings show that fatty acid metabolism in human T lymphocytes changes across the life course in a manner that may facilitate the adaptation of immune function to different life stages.
Topics: Adult; Humans; Fatty Acids; alpha-Linolenic Acid; T-Lymphocytes; Fatty Acids, Omega-3; Fatty Acids, Monounsaturated; Fatty Acids, Omega-6
PubMed: 36582247
DOI: 10.3389/fimmu.2022.1079642 -
The Proceedings of the Nutrition Society May 2020α-Linolenic acid (ALA) is an n-3 fatty acid found in plant-derived foods such as linseeds and linseed oil. Mammals can convert this essential fatty acid into...
α-Linolenic acid (ALA) is an n-3 fatty acid found in plant-derived foods such as linseeds and linseed oil. Mammals can convert this essential fatty acid into longer-chain fatty acids including EPA, docosapentaenoic acid (DPA) and DHA. Women demonstrate greater increases in the EPA status after ALA supplementation than men, and a growing body of animal model research identifies mechanisms by which sex hormones such as oestrogen and progesterone interact with the synthesis of EPA and DHA. Alternatively, EPA, DPA and DHA can be consumed directly, with oily fish being a rich dietary source of these nutrients. However, current National Diet and Nutrition Data reveals a median oily fish intake of 0 g daily across all age ranges and in both sexes. As longer-chain n-3 fatty acids have a crucial role in fetal and neonatal brain development, advice to consume dietary ALA could prove to be a pragmatic and acceptable alternative to advice to consume fish during pregnancy, if benefits upon tissue composition and functional outcomes can be demonstrated. Further research is required to understand the effects of increasing dietary ALA during pregnancy, and will need to simultaneously address conflicts with current dietary advice to only eat 'small amounts' of vegetable oils during pregnancy. Improving our understanding of sex-specific differences in fatty acid metabolism and interactions with pregnancy has the potential to inform both personalised nutrition advice and public health policy.
Topics: Animals; Diet; Dietary Fats; Dietary Supplements; Fatty Acids, Omega-3; Female; Gonadal Steroid Hormones; Humans; Male; Pregnancy; Sex Characteristics; alpha-Linolenic Acid
PubMed: 31416488
DOI: 10.1017/S0029665119001071 -
Progress in Lipid Research Jul 2015Docosahexaenoic acid (DHA) is important for brain function, and can be obtained directly from the diet or synthesized in the body from α-linolenic acid (ALA). Debate... (Review)
Review
Docosahexaenoic acid (DHA) is important for brain function, and can be obtained directly from the diet or synthesized in the body from α-linolenic acid (ALA). Debate exists as to whether DHA synthesized from ALA can provide sufficient DHA for the adult brain, as measures of DHA synthesis from ingested ALA are typically <1% of the oral ALA dose. However, the primary fate of orally administered ALA is β-oxidation and long-term storage in adipose tissue, suggesting that DHA synthesis measures involving oral ALA tracer ingestion may underestimate total DHA synthesis. There is also evidence that DHA synthesized from ALA can meet brain DHA requirements, as animals fed ALA-only diets have brain DHA concentrations similar to DHA-fed animals, and the brain DHA requirement is estimated to be only 2.4-3.8 mg/day in humans. This review summarizes evidence that DHA synthesis from ALA can provide sufficient DHA for the adult brain by examining work in humans and animals involving estimates of DHA synthesis and brain DHA requirements. Also, an update on methods to measure DHA synthesis in humans is presented highlighting a novel approach involving steady-state infusion of stable isotope-labeled ALA that bypasses several limitations of oral tracer ingestion. It is shown that this method produces estimates of DHA synthesis that are at least 3-fold higher than brain uptake rates in rats.
Topics: Animals; Biosynthetic Pathways; Brain; Diet; Docosahexaenoic Acids; Humans; alpha-Linolenic Acid
PubMed: 25920364
DOI: 10.1016/j.plipres.2015.04.002 -
International Journal of Molecular... Apr 2024The plant-derived α-linolenic acid (ALA) is an essential n-3 acid highly susceptible to oxidation, present in oils of flaxseeds, walnuts, canola, perilla, soy, and... (Review)
Review
The plant-derived α-linolenic acid (ALA) is an essential n-3 acid highly susceptible to oxidation, present in oils of flaxseeds, walnuts, canola, perilla, soy, and chia. After ingestion, it can be incorporated in to body lipid pools (particularly triglycerides and phospholipid membranes), and then endogenously metabolized through desaturation, elongation, and peroxisome oxidation to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with a very limited efficiency (particularly for DHA), beta-oxidized as an energy source, or directly metabolized to C18-oxilipins. At this moment, data in the literature about the effects of ALA supplementation on metabolic syndrome (MetS) in humans are inconsistent, indicating no effects or some positive effects on all MetS components (abdominal obesity, dyslipidemia, impaired insulin sensitivity and glucoregulation, blood pressure, and liver steatosis). The major effects of ALA on MetS seem to be through its conversion to more potent EPA and DHA, the impact on the n-3/n-6 ratio, and the consecutive effects on the formation of oxylipins and endocannabinoids, inflammation, insulin sensitivity, and insulin secretion, as well as adipocyte and hepatocytes function. It is important to distinguish the direct effects of ALA from the effects of EPA and DHA metabolites. This review summarizes the most recent findings on this topic and discusses the possible mechanisms.
Topics: Metabolic Syndrome; Humans; alpha-Linolenic Acid; Animals; Fatty Acids, Unsaturated; Dietary Supplements; Insulin Resistance
PubMed: 38732139
DOI: 10.3390/ijms25094909