Immune Function

The Impact of Omega-3 LCPUFA on Colorectal Cancer Development Guides Clinical Research towards Considering Immune Modulation and Regulation of Genomic Stability

This article at a glance In adults that develop colorectal cancer, survival is increased if omega-3 LCPUFA intake is modestly increased after diagnosis. Large prospective cohort studies tracked colorectal cancer incidence and assessed genomic stability and immune cell composition of tumors in relation to dietary intake of omega-3 long-chain polyunsaturated fatty acids (omega-3 LCPUFA). The risk of developing tumors characterized by higher genomic instability and richer in infiltrates of T-regulatory lymphocyte cells was significantly reduced in people with higher dietary intakes of omega-3 LCPUFA.   Colorectal cancer, or cancer of…

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Regulation of B-cell IgE Production by a DHA-Derived Lipid Mediator

This article at a glance This study assessed the effect of DHA-derived lipid mediators on IgE formation by B-lymphocytes, an important component of the adaptive immune system that is activated in allergies. The study reports that resolvin D1 inhibits the differentiation of human B-cells to an IgE-producing type by inhibiting B-cell isotype class-switching. The results of this study point to the activation of a new mechanism of anti-inflammatory action of omega-3 LCPUFA, and opens up research possibilities into modulating IgE-mediated allergic reactions in a novel way.   Immunoglobulin ɛ (IgE) is…

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Making PUFAs Available for Tissue Protection – Selective Phospholipase-Mediated Membrane Release of Omega-3 LCPUFA

This article at a glance A recent study in mice reports that human and mouse secretory group X phospholipase A2 preferentially releases omega-3 long-chain polyunsaturated fatty acids to serve anti-inflammatory and tissue-protective activities in the colon. Selective release of arachidonic acid by a different phospholipase, coupled to the biosynthesis of prostaglandin E2, occurs in parallel, and also contributes to the tissue-protective activity. Growing recognition of the involvement of distinct phospholipases in specific immunological events may one day allow us to better support their activities to drive beneficial outcomes.   In general…

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Modulation of the Acute Phase Response by Polyunsaturated Fatty Acids in Older People

This article at a glance Two recently published studies report on the relations between dietary intake and levels of poly-unsaturated fatty acids (PUFA) in blood and the acute phase response C-reactive protein (CRP) in older people. In one study, the omega-3 index was negatively associated with the levels of CRP and several other circulating markers of inflammation. In a second study, higher intake of omega-6 PUFA, and total PUFA, but not omega-3 PUFA, were found to be negatively associated with CRP, particularly in older women. The results reflect current challenges…

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Short-term Perioperative EPA/DHA Supplementation for Immune Modulation and Long-term Outcome; New Developments

This article at a glance Three recent studies have looked at different aspects of early post-surgical immune-modulatory effects of perioperative supplementation with EPA/DHA. These include lowered neutrophil activation potential, a decreased neutrophil-to-lymphocyte ratio, and reduced need for antibiotics. Short-term supplementation may lead to long-term benefits that had not been recognized previously, and that merit further investigation.   The long-chain omega-3 polyunsaturated fatty acids (omega-3 LCPUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been recognized to impart immune-modulatory activity for some time now. An endogenous role for EPA and DHA…

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EPA for Remission of Autoimmune Small-Vessel Vasculitis

This article at a glance In two clinical cases, EPA was recognized to possibly offer support to the long-term remission of autoimmune small vessel vasculitis, when used in combination with methylprednisolone and aspirin. The study next addressed the mechanisms whereby this may occur. A potential role for EPA as an adjunct to drug treatment for attenuating the activity of autoimmune ANCA-associated vasculitides deserves to be tested in properly designed trials.   Auto-immune diseases place a significant burden on society since they are chronic, affect a substantial percentage of the population (approximately…

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Circulating Specialized Proresolving Lipid Mediators after Short-term EPA/DHA-Supplementation

This article at a glance This study addressed the levels of anti-inflammatory and resolution-promoting lipid mediators derived from EPA and DHA in human plasma during oral supplementation with EPA/DHA over a relatively short period of five days. The potential effect of aspirin on the selective formation of stereoisomers of several derivatives was also assessed. The results show that resolvin E1 in plasma is sensitive to supplementation, and that one of the most recently discovered resolvins, RvE3, is present in the circulation.   Over the past few years a series of novel…

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Reference Profiles for PUFA-derived Lipid Mediators in Human Plasma and Serum

The long chain polyunsaturated fatty acids (PUFA) arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are used by the body to produce lipid mediators, which are derivatives with a variety of functions including regulating inflammatory responses, while protecting tissues against inflammatory insult and infection. AA, EPA and DHA are substrates for enzymatic reactions that incorporate oxygen at specific locations in the fatty acid molecule with a well-defined stereospecificity (spatial orientation), underlying the formation of lipid mediators called eicosanoids when derived from AA and EPA (with 20 carbons) and…

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DHA-Derived Maresins from Macrophages Inhibit Experimental Colitis in Animals

One of the most rapidly advancing areas of immune function research is the elucidation of a variety of anti-inflammatory, pro-resolving mediators derived from long-chain omega-3 PUFAs (n-3 LC-PUFAs), including EPA, DHA and n-3 DPA (docosapentaenoic acid) produced at the site of inflammation. To date, these substances include resolvins, protectins, maresins and most recently, pro-resolving mediators derived from n-3 DPA. Collectively, these mediators are known as specialized pro-resolving mediators (SPM). These substances counteract the inflammatory effects of arachidonic acid-derived eicosanoids, such as leukotriene B4 and prostaglandin E2. They halt the spread…

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Unesterified DHA Protects Against Neuroinflammation in Animal Study

DHA, the major PUFA in the brain, is required for optimal fetal and infant development of the brain, retina and nervous system and is vital for the healthy functioning of these tissues throughout life. DHA is important in many cell communication pathways, in the ability of neuronal connections to adapt (synaptic plasticity) and for neurite growth, to name several functions. DHA is also the precursor of several specialized pro-resolving mediators (SPM) that actively reduce inflammation and promote homeostasis in tissues. These mediators include resolvins, (neuro)protectins and maresins, which have been…

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