ABSTRACT
PURPOSE: This study aimed to investigate the effects of 12 wk of omega-3 fatty acid supplementation during endurance training on omega-3 index (O3I) and indicators of running performance in amateur long-distance runners. METHODS: Twenty-six amateur male long-distance runners ≥29 yr old supplemented omega-3 fatty acid capsules (OMEGA group, n = 14; 2234 mg of eicosapentaenoic acid and 916 mg of docosahexaenoic acid daily) or medium-chain triglycerides capsules as placebo (medium-chain triglyceride [MCT] group, n = 12; 4000 mg of MCT daily) during 12 wk of endurance training. Before and after intervention, blood samples were collected for O3I assessment, and an incremental test to exhaustion and a 1500-m run trial were performed. RESULTS: O3I was significantly increased in the OMEGA group (from 5.8% to 11.6%, P < 0.0001). A significant increase in VÌO 2peak was observed in the OMEGA group (from 53.6 ± 4.4 to 56.0 ± 3.7 mL·kg -1 â min -1 , P = 0.0219) without such change in MCT group (from 54.7 ± 6.8 to 56.4 ± 5.9 mL·kg -1 â min -1 , P = 0.1308). A positive correlation between the change in O3I and the change in running economy was observed when data of participants from both groups were combined (-0.1808 ± 1.917, P = 0.0020), without such an effect in OMEGA group alone ( P = 0.1741). No effect of omega-3 supplementation on 1500-m run results was observed. CONCLUSIONS: Twelve weeks of omega-3 fatty acid supplementation at a dose of 2234 mg of eicosapentaenoic acid and 916 mg of docosahexaenoic acid daily during endurance training resulted in the improvement of O3I and running economy and increased VÌO 2peak without improvement in the 1500-m run trial time in amateur runners.
Subject(s)
Dietary Supplements , Fatty Acids, Omega-3 , Running , Humans , Male , Docosahexaenoic Acids/physiology , Eicosapentaenoic Acid/physiology , Fatty Acids, Omega-3/physiology , Running/physiology , AdultABSTRACT
Fungal keratitis (FK) is one of the main causes of blindness in China. People with diabetes are susceptible to corneal epithelial disease, even fungal keratitis. At present, there are few studies on this disease. Resolvins (Rv) has been reported as a mediators that exert crucial anti-inflammatory and immune regulation roles in serval diseases. In order to investigate the roles and underlying mechanism of Resolvins D1 (RvD1) on the Aspergillus fumigatus (A. fumigatus) keratitis in diabetes, we established in vivo and in vitro models of A. fumigatus keratitis, which were then exposed to high glucose. The expression levels of RvD1, 5-lipoxygenase (5-LOX), and 15-lipoxygenase (15-LOX) in A. fumigatus keratitis patients with diabetes were determined through Enzyme Linked Immunosorbent Assay (ELISA), Western blot and immunohistochemistry. Reactive Oxygen Species (ROS) production, ELISA, flow cytometry, Hematoxylin-Eosin (HE) staining and fungal loading determination were conducted to evaluate the severity of A. fumigatus infection. Lymphangiogenesis and angiogenesis were examined by immunofluorescence assay. Western blot was applied to detect the proteins of the MAPK-NF-κB pathway. The results showed that RvD1 diminished the high glucose-induced oxidative stress and inflammatory response, as evidenced by the reduction of ROS production, Interleukin-6 (IL-6), Interleukin-8 (IL-8), Heme Oxygenase-1 (HMOX-1), and the elevation of Cyclooxygenase-2 (COX2), Superoxide Dismutase (SOD-1), and Glutathione Peroxidase-2 (GPX2) levels in A. fumigatus-infected Human Corneal Endothelial Cells (HCECs). Additionally, lymphangiogenesis and angiogenesis prominently decreased after intervention with RvD1. Furthermore, RvD1 significantly reduced the levels of p-MEK1/2 and p-ERK1/2, and restrained the NF-κB and GPR32 activation. The above results showed that RvD1 protects against A. fumigatus keratitis in diabetes by suppressing oxidative stress, inflammatory response, fungal growth, and immunoreaction via modulating MAPK-NF-κB pathway. RvD1 provides clues for the therapeutic targets of Fungal keratitis complicated with diabetes.
Subject(s)
Aspergillosis/prevention & control , Corneal Ulcer/prevention & control , Diabetes Complications/microbiology , Docosahexaenoic Acids/physiology , Eye Infections, Fungal/prevention & control , Mitogen-Activated Protein Kinase Kinases/metabolism , NF-kappa B/metabolism , Animals , Arachidonate 15-Lipoxygenase/metabolism , Arachidonate 5-Lipoxygenase/metabolism , Aspergillosis/metabolism , Aspergillosis/microbiology , Aspergillus fumigatus/physiology , Blotting, Western , Cells, Cultured , Corneal Ulcer/metabolism , Corneal Ulcer/microbiology , Diabetes Complications/metabolism , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Epithelium, Corneal/drug effects , Epithelium, Corneal/microbiology , Eye Infections, Fungal/metabolism , Eye Infections, Fungal/microbiology , Flow Cytometry , Glucose/pharmacology , Humans , Immunohistochemistry , Mice, Inbred C57BL , Oxidative Stress/drug effects , Oxidoreductases/metabolism , Reactive Oxygen Species/metabolismABSTRACT
BACKGROUND: The aim of the present study was to examine the relation between adipose tissue content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the risk of incident atrial fibrillation (AF). METHODS: In this case-cohort study based on data from the Danish Diet, Cancer and Health cohort, a total of 5255 incident cases of AF was identified during 16.9 years of follow-up. Adipose tissue biopsies collected at baseline from all cases and from a randomly drawn subcohort of 3440 participants were determined by gas chromatography. Data were analysed using weighted Cox regression. RESULTS: Data were available for 4741 incident cases of AF (2920 men and 1821 women). Participants in the highest vs. the lowest quintile of EPA experienced a 45% lower risk of AF (men HR 0.55 (95% CI 0.41-0.69); women HR 0.55 (0.41-0.72)). For DHA, no clear association was found in men, whereas in women, participants in the highest quintile of DHA in adipose tissue had a 30% lower risk of incident AF (HR 0.70 (0.54-0.91)) compared to participants in the lowest quintile. CONCLUSIONS: A monotonous inverse association was found for the content of EPA in adipose tissue and risk of AF in both men and women. The content of DHA was inversely associated with the risk of AF in women, whereas no clear association was found for men.
Subject(s)
Adipose Tissue/chemistry , Atrial Fibrillation/epidemiology , Atrial Fibrillation/etiology , Docosahexaenoic Acids/analysis , Docosahexaenoic Acids/physiology , Eicosapentaenoic Acid/analysis , Eicosapentaenoic Acid/physiology , Cohort Studies , Female , Humans , Male , Middle Aged , Risk AssessmentABSTRACT
Olfactory dysfunction is observed in several neurological disorders including Mild Cognitive Impairment (MCI) and Alzheimer disease (AD). These deficits occur early and correlate with global cognitive performance, depression and degeneration of olfactory regions in the brain. Despite extensive human studies, there has been little characterization of the olfactory system in models of AD. In order to determine if olfactory structural and/or molecular phenotypes are observed in a model expressing a genetic risk factor for AD, we assessed the olfactory bulb (OB) in APOE4 transgenic mice. A significant decrease in OB weight was observed at 12 months of age in APOE4 mice concurrent with inflammation and decreased NeuN expression. In order to determine if a diet rich in omega-3s may alleviate the olfactory system phenotypes observed, we assessed WT and APOE4 mice on a docosahexaenoic acid (DHA) diet. APOE4 mice on a DHA diet did not present with atrophy of the OB, and the alterations in NeuN and IBA-1 expression were alleviated. Furthermore, alterations in caspase mRNA and protein expression in the APOE4 OB were not observed with a DHA diet. Similar to the human AD condition, OB atrophy is an early phenotype in the APOE4 mice and concurrent with inflammation. These data support a link between the structural olfactory brain region atrophy and the olfactory dysfunction observed in AD and suggest that inflammation and cell death pathways may contribute to the olfactory deficits observed. Furthermore, the results suggest that diets enriched in DHA may provide benefit to APOE4 allele carriers.
Subject(s)
Alzheimer Disease , Apolipoprotein E4 , Docosahexaenoic Acids/physiology , Olfaction Disorders/diet therapy , Olfactory Bulb , Alzheimer Disease/complications , Alzheimer Disease/genetics , Animals , Apolipoprotein E4/genetics , Atrophy , Diet , Disease Models, Animal , Mice , Mice, Transgenic , Olfaction Disorders/etiology , Olfaction Disorders/genetics , Olfactory Bulb/growth & development , Olfactory Bulb/metabolism , Olfactory Bulb/pathologyABSTRACT
During the last trimester of gestation and for the first 18 months after birth, both docosahexaenoic acid,22:6n-3 (DHA) and arachidonic acid,20:4n-6 (ARA) are preferentially deposited within the cerebral cortex at a rapid rate. Although the structural and functional roles of DHA in brain development are well investigated, similar roles of ARA are not well documented. The mode of action of these two fatty acids and their derivatives at different structural-functional roles and their levels in the gene expression and signaling pathways of the brain have been continuously emanating. In addition to DHA, the importance of ARA has been much discussed in recent years for fetal and postnatal brain development and the maternal supply of ARA and DHA. These fatty acids are also involved in various brain developmental processes; however, their mechanistic cross talks are not clearly known yet. This review describes the importance of ARA, in addition to DHA, in supporting the optimal brain development and growth and functional roles in the brain.
Subject(s)
Arachidonic Acid/physiology , Brain/growth & development , Docosahexaenoic Acids/physiology , Maternal Nutritional Physiological Phenomena , Animals , Arachidonic Acid/deficiency , Brain/embryology , Brain/metabolism , Child Development , Docosahexaenoic Acids/deficiency , Female , Humans , Infant , Maternal Nutritional Physiological Phenomena/physiologyABSTRACT
Inflammatory cell infiltration contributes to the pathogenesis of acute respiratory distress syndrome (ARDS). Protectin DX (PDX), an endogenous lipid mediator, shows anti-inflammatory and proresolution bioactions. In vivo, the mice were intraperitoneally injected with PDX (0.1 µg/mouse) after intratracheal (1 mg/kg) or intraperitoneal (10 mg/kg) LPS administration. Flow cytometry was used to measure inflammatory cell numbers. Clodronate liposomes were used to deplete resident macrophages. RT-PCR, and ELISA was used to measure MIP-2, MCP-1, TNF-α and MMP9 levels. In vitro, sorted neutrophils, resident and recruited macrophages (1 × 106 ) were cultured with 1 µg/mL LPS and/or 100 nmol/L PDX to assess the chemokine receptor expression. PDX attenuated LPS-induced lung injury via inhibiting recruited macrophage and neutrophil recruitment through repressing resident macrophage MCP-1, MIP-2 expression and release, respectively. Finally, PDX inhibition of neutrophil infiltration and transmembrane was associated with TNF-α/MIP-2/MMP9 signalling pathway. These data suggest that PDX attenuates LPS-stimulated lung injury via reduction of the inflammatory cell recruitment mediated via resident macrophages.
Subject(s)
Acute Lung Injury/pathology , Docosahexaenoic Acids/therapeutic use , Macrophages/drug effects , Acute Lung Injury/chemically induced , Administration, Intranasal , Animals , Chemokine CCL2/biosynthesis , Chemokine CCL2/genetics , Chemokine CXCL2/biosynthesis , Chemokine CXCL2/genetics , Chemokine CXCL2/physiology , Chemotaxis, Leukocyte/drug effects , Clodronic Acid/administration & dosage , Clodronic Acid/pharmacology , Docosahexaenoic Acids/pharmacology , Docosahexaenoic Acids/physiology , Inflammation , Injections, Intraperitoneal , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/toxicity , Liposomes , Macrophages/physiology , Matrix Metalloproteinase 9/physiology , Mice , Mice, Inbred C57BL , Neutrophils/drug effects , Receptors, CCR2/antagonists & inhibitors , Receptors, Interleukin-8B/antagonists & inhibitors , Signal Transduction/drug effects , Transendothelial and Transepithelial Migration/drug effects , Tumor Necrosis Factor-alpha/physiologyABSTRACT
There is no consensus on the effects of omega-3 (ω-3) fatty acids (FA) on cutaneous repair. To solve this problem, we used 2 different approaches: (1) FAT-1 transgenic mice, capable of producing endogenous ω-3 FA; (2) wild-type (WT) mice orally supplemented with DHA-enriched fish oil. FAT-1 mice had higher systemic (serum) and local (skin tissue) ω-3 FA levels, mainly docosahexaenoic acid (DHA), in comparison with WT mice. FAT-1 mice had increased myeloperoxidase (MPO) activity and content of CXCL-1 and CXCL-2, and reduced IL-10 in the skin wound tissue three days after the wound induction. Inflammation was maintained by an elevated TNF-α concentration and presence of inflammatory cells and edema. Neutrophils and macrophages, isolated from FAT-1 mice, also produced increased TNF-α and reduced IL-10 levels. In these mice, the wound closure was delayed, with a wound area 6-fold bigger in relation with WT group, on the last day of analysis (14 days post-wounding). This was associated with poor orientation of collagen fibers and structural aspects in repaired tissue. Similarly, DHA group had a delay during late inflammatory phase. This group had increased TNF-α content and CD45+F4/80+ cells at the third day after skin wounding and increased concentrations of important metabolites derived from ω-3, like 18-HEPE, and reduced concentrations of those from ω-6 FA. In conclusion, elevated DHA content, achieved in both FAT-1 and DHA groups, slowed inflammation resolution and impaired the quality of healed skin tissue.
Subject(s)
Docosahexaenoic Acids/physiology , Wound Healing , Animals , Caenorhabditis elegans , Caenorhabditis elegans Proteins/genetics , Dietary Supplements , Fatty Acid Desaturases/genetics , Inflammation , Macrophages/physiology , Male , Mice, Transgenic , Neutrophils/physiology , Skin/metabolismABSTRACT
BACKGROUND AND AIMS: Higher blood levels of the omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been associated with fewer cardiovascular events and lower mortality in prospective studies. Our aim was to determine a target level of EPA and DHA to prevent progression of coronary artery plaque. METHODS: 218 subjects with stable coronary artery disease on statins were randomized to high-dose EPA and DHA (3.36 g daily) or no omega-3 for 30 months. Coronary plaque volume was measured by coronary computed tomographic angiography. Plasma phospholipid levels of EPA, DHA and total fatty acids were measured by gas chromatography mass spectrometry. The omega-3 fatty acid index was calculated as EPA+DHA/total fatty acid. RESULTS: Mean (SD) age was 62.9 (7.8) years; mean (SD) LDL-C level 78.6 (27.3) mg/dL and median triglyceride level 122â¯mg/dL. Subjects assigned to EPA and DHA had increased plasma EPA and DHA levels variably from 1.85% to 13.02%. Plasma omega-3 fatty acid index ≥4% prevented progression of fibrous, noncalcified, calcified and total plaque in nondiabetic subjects whereas those in the lowest quartile (<3.43%) had significant progression of fibrous, calcified and total plaque. No difference was observed in diabetic subjects. CONCLUSIONS: EPA and DHA added to statins prevented coronary plaque progression in nondiabetic subjects with mean LDL-C <80â¯mg/dL, when an omega-3 index ≥4% was achieved. Low omega-3 index <3.43% identified nondiabetic subjects at risk of coronary plaque progression despite statin therapy. These findings highlight the importance of measuring plasma levels of omega-3 fatty acids early and at trial conclusion. Targeting an omega-3 index ≥4% maximizes cardiovascular benefit.
Subject(s)
Coronary Artery Disease/blood , Coronary Artery Disease/drug therapy , Docosahexaenoic Acids/blood , Eicosapentaenoic Acid/blood , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Plaque, Atherosclerotic/blood , Aged , Coronary Artery Disease/complications , Coronary Artery Disease/prevention & control , Disease Progression , Docosahexaenoic Acids/physiology , Eicosapentaenoic Acid/physiology , Female , Humans , Male , Middle Aged , Plaque, Atherosclerotic/complications , Plaque, Atherosclerotic/prevention & controlABSTRACT
Under physiologic conditions, conjunctival goblet cells (CGCs) secrete mucins into the tear film to preserve ocular surface homeostasis. Specialized proresolving mediators (SPMs), like resolvins (Rvs), regulate secretion from CGCs and actively terminate inflammation. The purpose of this study was to determine if RvD2 stimulated mucin secretion and to investigate the cellular signaling components. Goblet cells were cultured from rat conjunctiva. Secretion was measured by an enzyme-linked lectin assay, change in intracellular [Ca2+] ([Ca2+]i) using Fura-2, and cellular cAMP levels by ELISA. RvD2 (10-11-10-8 M) stimulated secretion, increased cellular cAMP levels and the [Ca2+]i. RvD2-stimulated increase in [Ca2+]i and secretion was blocked by Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis and the PKA inhibitor N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride but not by the cAMP exchange protein inhibitor α-[2-(3-chlorophenyl)hydrazinylidene]-5-(1,1-dimethylethyl)-b-oxo-3-isoxazolepropanenitrile. Forskolin, 3-isobutyl-1-methylxanthine, and 8-bromo-cAMP (8-Br-cAMP) increased [Ca2+]i. Increasing cAMP with 8-Br-cAMP inhibited the increase in [Ca2+]i stimulated by the cAMP-independent agonist cholinergic agonist carbachol. In conclusion, RvD2 uses both cellular cAMP and [Ca2+]i to stimulate glycoconjugate secretion from CGCs, but the interaction of cAMP and [Ca2+]i is context dependent. Thus RvD2 likely assists in the maintenance of the mucous layer of the tear film to sustain ocular surface homeostasis and has potential as a novel treatment for dry eye disease.-Botten, N., Hodges, R. R., Li, D., Bair, J. A., Shatos, M. A., Utheim, T. P., Serhan, C. N., Dartt, D. A. Resolvin D2 elevates cAMP to increase intracellular [Ca2+] and stimulate secretion from conjunctival goblet cells.
Subject(s)
Calcium/metabolism , Conjunctiva/drug effects , Conjunctiva/metabolism , Cyclic AMP/metabolism , Docosahexaenoic Acids/physiology , Goblet Cells/drug effects , Goblet Cells/metabolism , 8-Bromo Cyclic Adenosine Monophosphate/metabolism , Animals , Cells, Cultured , Dry Eye Syndromes/drug therapy , Dry Eye Syndromes/metabolism , Fura-2/metabolism , Male , Mucins/metabolism , Rats , Rats, Sprague-Dawley , Tears/drug effects , Tears/metabolismABSTRACT
Excessive chronic inflammation is linked to many diseases and considered a stress factor in humans (Robbins Pathologic Basis of Disease. Philadelphia: W.B. Saunders Co., 1999, Proc Natl Acad Sci USA, 2008, 105: 17949, Immunity, 44, 2016, 44: 463, N Engl J Med, 2011, 364: 656). Today, the resolution of inflammation is widely recognized as a cellular biochemically active process involving biosynthesis of a novel superfamily of endogenous chemical signals coined specialized pro-resolving mediators (SPMs; Nature, 2014, 510:92). Herein, we review recent evidence, indicating a role for the vagus nerve and vagotomy in the regulation of lipid mediators. Vagotomy reduces pro-resolving mediators, including the lipoxins, resolvins, protectins and maresins, delaying resolution in mouse peritonitis. Vagotomy also delays resolution of Escherichia coli infection in mice. Specifically, right vagus regulates peritoneal Group 3 innate lymphoid cell (ILC-3) number and peritoneal macrophage responses with lipid mediator profile signatures with elevated pro-inflammatory eicosanoids and reduced resolvins, including the novel protective immunoresolvent agonist protectin conjugate in tissue regeneration1 (PCTR1). Acetylcholine upregulates PCTR biosynthesis, and administration of PCTR1 to vagotomized mice restores tissue resolution and host responses to E. coli infections. Results obtained with human vagus ex vivo indicate that vagus can produce both pro-inflammatory eicosanoids, such as prostaglandins and leukotrienes, as well as the SPM. Electrical stimulation of human vagus in vitro reduces both prostaglandins and leukotrienes and enhances resolvins and the other SPM. These results elucidate a host protective mechanism mediated by vagus stimulation of SPM that includes resolvins and PCTR1 to regulate myeloid antimicrobial functions and resolution of infection. Moreover, they define a new pro-resolution of inflammation reflex operative in mice and human tissue that involves a vagus SPM circuit.
Subject(s)
Inflammation Mediators/physiology , Inflammation/physiopathology , Vagotomy , Vagus Nerve/physiology , Acute Disease , Animals , CD59 Antigens/physiology , Docosahexaenoic Acids/physiology , Exudates and Transudates/physiology , Fatty Acids, Essential/physiology , Leukocytes/physiology , Lipid Metabolism/physiology , Mice , Neuroprotection/physiology , Signal Transduction/physiology , Vagus Nerve/surgeryABSTRACT
BACKGROUND: The French National survey INCA2 pointed out that the majority of the French population (children, adolescents, adults and elderly) ingest low quantities of n-3 polyunsaturated fatty acid (PUFA) in the form of both precursor (alpha-linolenic acid, ALA) and long-chain (mainly docosahexaenoic acid, DHA). However, we don't know whether such inadequate n-3 PUFA consumption is also found again in pregnant and lactating women. METHODS: Dietary lipid and PUFA intakes were determined from 28 pregnant and 21 lactating French women by using the most recent set of national robust data on food (National Survey INCA2 performed in 2006 and 2007), and compared with that of 742 women of childbearing age. RESULTS: Main results showed that mean daily intakes of n-3 PUFA were very low in this French woman population because no pregnant and lactating women met recommended dietary intakes (RDIs). Moreover, some of them ingested quantities 4 times (ALA) to 10 times (DHA) lower than RDIs. Very similar dietary intakes were observed in women of childbearing age. CONCLUSION: French pregnant and lactating women did not change their dietary habits to favor ALA and n-3 long-chain PUFA consumption via rich-ALA vegetable oils and fish and oily fish consumption, and have low n-3 PUFA dietary consumption typical of French women of childbearing age. Such PUFA intakes could have adverse impact on long-chain n-3 PUFA incorporation in brain membranes of fetus and infants, but also on cognitive and visual development of infants during the first years of life.
Subject(s)
Diet, Fat-Restricted/adverse effects , Docosahexaenoic Acids/physiology , Lactation , Prenatal Nutritional Physiological Phenomena , Recommended Dietary Allowances , alpha-Linolenic Acid/physiology , Adult , Feeding Behavior , Female , France , Humans , Middle Aged , Plant Oils , Pregnancy , Seafood , Surveys and Questionnaires , Young AdultABSTRACT
Docosahexaenoic acid (DHA, 22:6) is an n-3 polyunsaturated fatty acid (n-3 PUFA) that influences immunological, metabolic, and neurological responses through complex mechanisms. One structural mechanism by which DHA exerts its biological effects is through its ability to modify the physical organization of plasma membrane signaling assemblies known as sphingomyelin/cholesterol (SM/chol)-enriched lipid rafts. Here we studied how DHA acyl chains esterified in the sn-2 position of phosphatidylcholine (PC) regulate the formation of raft and non-raft domains in mixtures with SM and chol on differing size scales. Coarse grained molecular dynamics simulations showed that 1-palmitoyl-2-docosahexaenoylphosphatylcholine (PDPC) enhances segregation into domains more than the monounsaturated control, 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC). Solid state 2H NMR and neutron scattering experiments provided direct experimental evidence that substituting PDPC for POPC increases the size of raft-like domains on the nanoscale. Confocal imaging of giant unilamellar vesicles with a non-raft fluorescent probe revealed that POPC had no influence on phase separation in the presence of SM/chol whereas PDPC drove strong domain segregation. Finally, monolayer compression studies suggest that PDPC increases lipid-lipid immiscibility in the presence of SM/chol compared to POPC. Collectively, the data across model systems provide compelling support for the emerging model that DHA acyl chains of PC lipids tune the size of lipid rafts, which has potential implications for signaling networks that rely on the compartmentalization of proteins within and outside of rafts.
Subject(s)
Docosahexaenoic Acids/physiology , Membrane Microdomains/chemistry , Calorimetry, Differential Scanning/methods , Cholesterol/chemistry , Docosahexaenoic Acids/chemistry , Lipid Bilayers/chemistry , Magnetic Resonance Spectroscopy , Membrane Microdomains/physiology , Molecular Dynamics Simulation , Phosphatidylcholines/chemistry , Phosphatidylcholines/physiology , Phosphatidylethanolamines/chemistry , Sphingomyelins/chemistryABSTRACT
Formyl peptide receptor 2/lipoxin A4 (LXA4) receptor (Fpr2/ALX) co-ordinates the transition from inflammation to resolution during acute infection by binding to distinct ligands including serum amyloid A (SAA) and Resolvin D1 (RvD1). Here, we evaluated the proresolving actions of aspirin-triggered RvD1 (AT-RvD1) in an acute coinfection pneumonia model. Coinfection with Streptococcus pneumoniae and influenza A virus (IAV) markedly increased pneumococcal lung load and neutrophilic inflammation during the resolution phase. Fpr2/ALX transcript levels were increased in the lungs of coinfected mice, and immunohistochemistry identified prominent Fpr2/ALX immunoreactivity in bronchial epithelial cells and macrophages. Levels of circulating and lung SAA were also highly increased in coinfected mice. Therapeutic treatment with exogenous AT-RvD1 during the acute phase of infection (day 4-6 post-pneumococcal inoculation) significantly reduced the pneumococcal load. AT-RvD1 also significantly reduced neutrophil elastase (NE) activity and restored total antimicrobial activity in bronchoalveolar lavage (BAL) fluid (BALF) of coinfected mice. Pneumonia severity, as measured by quantitating parenchymal inflammation or alveolitis was significantly reduced with AT-RvD1 treatment, which also reduced the number of infiltrating lung neutrophils and monocytes/macrophages as assessed by flow cytometry. The reduction in distal lung inflammation in AT-RvD1-treated mice was not associated with a significant reduction in inflammatory and chemokine mediators. In summary, we demonstrate that in the coinfection setting, SAA levels were persistently increased and exogenous AT-RvD1 facilitated more rapid clearance of pneumococci in the lungs, while concurrently reducing the severity of pneumonia by limiting excessive leukocyte chemotaxis from the infected bronchioles to distal areas of the lungs.
Subject(s)
Aspirin/therapeutic use , Coinfection/drug therapy , Docosahexaenoic Acids/physiology , Orthomyxoviridae Infections/complications , Pneumonia, Pneumococcal/complications , Animals , Aspirin/pharmacology , Bacterial Load/drug effects , Disease Models, Animal , Docosahexaenoic Acids/metabolism , Flow Cytometry , Influenza A virus , Lung/microbiology , Male , Mice , Mice, Inbred C57BL , Orthomyxoviridae Infections/drug therapy , Pneumonia, Pneumococcal/drug therapy , Receptors, Formyl Peptide/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Streptococcus pneumoniae , TranscriptomeABSTRACT
Docosahexaenoic acid (DHA) is a long-chain, highly unsaturated omega-3 (n-3) fatty acid. It has a structure that gives it unique physical and functional properties. DHA is metabolically related to other n-3 fatty acids: it can be synthesised from the plant essential fatty acid α-linolenic acid (ALA). However, this pathway does not appear to be very efficient in many individuals, although the conversion of ALA to DHA is much better in young women than in young men. Furthermore, young infants may be more efficient converters of ALA to DHA than many adults, although the conversion rate is variable among infants. Many factors have been identified that affect the rate of conversion. The implication of poor conversion is that preformed DHA needs to be consumed. DHA is found in fairly high amounts in seafood, especially fatty fish, and in various forms of n-3 supplements. The amount of DHA in seafood and in supplements varies. Breast milk contains DHA. DHA is found esterified into complex lipids within the bloodstream, in adipose stores and in cell membranes. Its concentration in different compartments varies greatly. The brain and eye have high DHA contents compared to other organs. DHA is especially concentrated in the grey matter of the brain and in the rod outer segments of the retina. In the brain DHA is involved in neuronal signalling, while in the eye it is involved in the quality of vision. DHA is accumulated in the brain and eye late in pregnancy and in early infancy. A lower DHA content is linked to poorer cognitive development and visual function. DHA affects cell and tissue physiology and function through numerous mechanisms, including alterations in membrane structure and function, in membrane protein function, in cellular signalling and in lipid mediator production.
Subject(s)
Brain/metabolism , Docosahexaenoic Acids/physiology , Infant Nutritional Physiological Phenomena , Adult , Age Factors , Dietary Supplements/analysis , Docosahexaenoic Acids/biosynthesis , Female , Humans , Infant , Infant, Newborn , Male , Milk, Human/chemistry , Seafood/analysis , Sex Factors , alpha-Linolenic Acid/metabolismABSTRACT
Docosahexaenoic acid (DHA), a long-chain polyunsaturated fatty acid, is essential for normal brain development. DHA is found predominantly in seafood, fish oil, breastmilk and supplemented formula. DHA intake in Western countries is often below recommendations. Observational studies have demonstrated an association between DHA intake in pregnancy and neurodevelopment of offspring but cannot fully adjust for confounding factors that influence child development. Randomised clinical trials of DHA supplementation during pregnancy and/or lactation, and of term infants, have not shown a consistent benefit nor harm on neurodevelopment of healthy children born at term. The evidence does not support DHA supplementation of healthy pregnant and lactating women, nor healthy infants.
Subject(s)
Brain Chemistry/physiology , Brain/growth & development , Child Development/physiology , Docosahexaenoic Acids/physiology , Infant Nutritional Physiological Phenomena , Dietary Supplements , Eating , Female , Fish Oils , Humans , Infant , Male , Milk, Human/chemistry , Observational Studies as Topic , Pregnancy , Prenatal Nutritional Physiological Phenomena , Randomized Controlled Trials as Topic , Term BirthABSTRACT
Preterm birth accounts for more than 85% of all perinatal complications and deaths. There are many short- and long-term consequences of being born too soon. These infants often require intensive care and are at increased risk of early morbidities often with life-long sequelae. Approximately 50% of all preterm births have unknown or unclear causes, and there are no effective primary prevention strategies in widespread clinical use. Epidemiological studies have observed an increased length of gestation in populations with high fish consumption. These findings have led to randomised controlled trials of omega-3 (n-3) long-chain polyunsaturated fatty acid (LCPUFA) supplementation which show that these dietary agents may delay the timing of birth and may have value as a prophylactic intervention in some women. This review presents the available evidence and discusses the relationship between prenatal n-3 LCPUFA supplementation during pregnancy and the incidence of preterm birth.
Subject(s)
Docosahexaenoic Acids/physiology , Fatty Acids, Omega-3/therapeutic use , Premature Birth/prevention & control , Prenatal Care/methods , Prenatal Nutritional Physiological Phenomena , Adult , Dietary Supplements , Female , Humans , Incidence , Infant, Newborn , Male , Pregnancy , Premature Birth/epidemiology , Premature Birth/etiology , Randomized Controlled Trials as TopicABSTRACT
Long-chain polyunsaturated fatty acids (LCPUFAs) play specific roles during the perinatal period and are very important nutrients to consider. The possible effects of LCPUFAs, particularly docosahexaenoic acid (DHA), on various clinical outcomes of preterm infants are discussed in this paper. Since DHA accumulates in the central nervous system during development, a lot of attention has focused on the effects of DHA on neurodevelopment. Experimental studies as well as recent clinical trials show that providing larger amounts of DHA than currently and routinely provided is associated with better neurological outcomes at 18 months to 2 years. This early advantage, however, does not seem to translate into detectable change in visual and neurodevelopmental outcomes or behavior when assessed in childhood. There is growing evidence that, in addition to effects on development, omega-3 LCPUFAs may reduce the incidence or severity of neonatal morbidities by affecting different steps of the immune and anti-inflammatory response. Studies in preterm infants suggest that the omega-3 LCPUFAs may play a significant role by reducing the risk of bronchopulmonary dysplasia, necrotizing enterocolitis and possibly retinopathy of prematurity and sepsis. Overall, evidence is increasing to support the benefits of high-dose DHA for various health outcomes of preterm infants. These findings are of major clinical relevance mainly because infants born preterm are at particularly high risk for a nutritional deficit in omega-3 fatty acids, predisposing to adverse neonatal outcomes. Further studies are warranted to address these issues as well as to more precisely determine the LCPUFA requirement in order to favor the best possible outcomes of preterm infants.
Subject(s)
Docosahexaenoic Acids/physiology , Fatty Acids, Omega-3/physiology , Fatty Acids, Unsaturated/physiology , Infant Nutritional Physiological Phenomena , Infant, Premature/metabolism , Female , Humans , Infant, Newborn , MaleSubject(s)
Fatty Acids, Omega-3/physiology , Docosahexaenoic Acids/administration & dosage , Docosahexaenoic Acids/physiology , Fatty Acids, Omega-3/administration & dosage , Female , Fetal Development/physiology , Humans , Infant , Infant, Newborn , Maternal-Fetal Exchange/physiology , Pregnancy , Pregnancy Outcome , Premature Birth/etiologyABSTRACT
BACKGROUND: Long chain polyunsaturated fatty acid (LCPUFA) status is associated with risk of cardiovascular diseases in adulthood. We previously demonstrated no effect of LCPUFA supplementation after birth on BP and anthropometrics. Little is known about the association between fatty acid status at birth and cardiometabolic health at older ages. AIM: To evaluate associations between docosahexaenoic acid (DHA) and arachidonic acid (AA) levels in the umbilical cord and blood pressure (BP) and anthropometrics at 9years. STUDY DESIGN: Observational follow-up study. Multivariable analyses were carried out to adjust for potential confounders. SUBJECTS: 229 children who took part in a randomized controlled trial (RCT) on the effects of LCPUFA formula supplementation. OUTCOME MEASURES: BP was chosen as primary outcome; heart rate and anthropometrics as secondary outcomes. RESULTS: AA levels in the wall of the umbilical vein and artery were negatively associated with diastolic BP (B: vein -0.831, 95% CI: -1.578; -0.083, p=0.030; artery: -0.605, 95% CI: -1.200; -0.010, p=0.046). AA was not associated with systolic BP; DHA not with diastolic nor systolic BP. The AA:DHA ratio in the umbilical vein was negatively associated with diastolic BP (B: -1.738, 95% CI: -3.141; -0.335, p=0.015). Heart rate and anthropometrics were not associated with neonatal LCPUFA status. CONCLUSIONS: Higher AA levels and a higher AA:DHA ratio at birth are associated with lower diastolic BP at age 9. This suggests that the effect of LCPUFAs at early age is different from that in adults, where DHA is regarded anti-adipogenic and AA as adipogenic.