Browsing by Subject "Polyunsaturated fatty acids"

Now showing 1 - 5 of 5
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    Association between plasma endocannabinoids and appetite in hemodialysis patients: A pilot study
    (Elsevier, 2016-07) Friedman, Allon N.; Kim, Jeffrey; Kaiser, Shaun; Pedersen, Theresa L.; Newman, John W.; Watkins, Bruce A.; Medicine, School of Medicine
    Uremia-associated anorexia may be related to altered levels of long chain n-6 and n-3 polyunsaturated fatty acid (PUFA) derived circulating endocannabinoids (EC) and EC-like compounds that are known to mediate appetite. Our study's hypothesis was that such molecules are associated with appetite in patients with end-stage renal disease. A cross-sectional observational study was performed in 20 chronic hemodialysis patients (9 females, 11 males) and 10 healthy female controls in whom appetite was assessed using the Simplified Nutritional Appetite Questionnaire (SNAQ) and blood drawn in the fasting (and when applicable) pre-dialysis state. Blood levels of PUFA and EC were also measured. Higher blood levels of the long chain n-6 fatty acid 20:4n6 (arachidonic acid) and lower levels of the long chain n-3 fatty acid 20:5n3 (eicosapentaenoic acid) were observed in female hemodialysis patients compared to controls. No differences were observed between male and female patients. In female study participants strong correlations between specific EC-like compounds and total SNAQ scores were noted, including with the n-6 PUFA derived linoleoyl ethanolamide (L-EA; ρ=-0.60, P<.01) and the n-3 PUFA derived docosahexaenoyl ethanolamide (DH-EA; ρ=0.63, P<.01). The L-EA:DH-EA ratio was most strongly associated with the SNAQ score (ρ=-0.74, P≤.001), and its questions associated with appetite (ρ=-0.69, P≤.01) and satiety (ρ=-0.81, P≤.001). These findings support a link between circulating EC and appetite in hemodialysis patients.
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    Blood Levels of Endocannabinoids, Oxylipins, and Metabolites Are Altered in Hemodialysis Patients
    (MDPI, 2022-08-29) Watkins, Bruce A.; Friedman, Allon N.; Kim, Jeffrey; Borkowski, Kamil; Kaiser, Shaun; Fiehn, Oliver; Newman, John W.; Medicine, School of Medicine
    Hemodialysis patients (HDPs) have higher blood pressure, higher levels of inflammation, a higher risk of cardiovascular disease, and unusually low plasma n-3 polyunsaturated fatty acid (PUFA) levels compared to healthy subjects. The objective of our investigation was to examine the levels of endocannabinoids (eCBs) and oxylipins (OxLs) in female HDPs compared to healthy matched female controls, with the underlying hypothesis that differences in specific PUFA levels in hemodialysis patients would result in changes in eCBs and OxLs. Plasma phospholipid fatty acids were analyzed by gas chromatography. Plasma was extracted and analyzed using ultra-performance liquid chromatography followed by electrospray ionization and tandem MS for eCBs and OxLs. The global untargeted metabolite profiling of plasma was performed by GCTOF MS. Compared to the controls, HDPs showed lower levels of plasma EPA and the associated OxL metabolites 5- and 12-HEPE, 14,15-DiHETE, as well as DHA derived 19(20)-EpDPE. Meanwhile, no changes in arachidonylethanolamide or 2-arachidonylglycerol in the open circulation were detected. Higher levels of multiple N-acylethanolamides, monoacylglycerols, biomarkers of progressive kidney disease, the nitric oxide metabolism-linked citrulline, and the uremic toxins kynurenine and creatine were observed in HDP. These metabolic differences in cCBs and OxLs help explain the severe inflammatory and cardiovascular disease manifested by HDPs, and they should be explored in future studies.
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    Dietary Fat and Fatty Acid Intake in Nulliparous Women: Associations with Preterm Birth and Distinctions by Maternal BMI
    (Oxford University Press, 2021-05-08) Robinson, Daniel T.; Van Horn, Linda; Balmert, Lauren; Silver, Robert M.; Parry, Samuel; Haas, David M.; Wing, Deborah A.; Grobman, William A.; Obstetrics and Gynecology, School of Medicine
    Background: Evidence documenting whether diet quality, particularly dietary fatty acids, is associated with preterm birth (PTB) is limited. Objective: The aim was to measure associations between dietary fatty acid intake prior to pregnancy, specifically n-3 (ɷ-3) PUFAs and odds of PTB in US women and determine if associations differed by prepregnancy BMI. Methods: We designed a secondary analysis of dietary intake in nulliparous women enrolled in a longitudinal cohort (NCT01322529). Participants completed an FFQ, modified to assess detailed PUFA intake, during the 3 mo preceding pregnancy. Inclusion in this analytic cohort required total energy intake within 2 SDs of the group mean. Prepregnancy BMI was categorized as underweight, normal, overweight, or obese. The primary exposure was estimated intake of EPA and DHA (combined EPA+DHA), in the context of a recommended intake of 250 mg. The primary outcome was PTB (<37 wk). Adjusted regression models controlled for maternal factors relevant to PTB and evaluated associations with PUFAs. Interaction terms estimated effect modification of BMI. A false discovery rate (FDR) correction accounted for multiple comparisons. Results: Median daily intake of combined EPA+DHA in 7365 women was 70 mg (IQR: 32, 145 mg). A significant interaction term indicated the effects of EPA+DHA on odds of PTB were different for different BMI categories (P < 0.01). Specifically, higher intake of combined EPA+DHA was nominally associated with reduced odds of PTB in women with underweight (OR: 0.67; 95% CI: 0.46-0.98) and normal BMI (OR: 0.87; 95% CI: 0.78-0.96), yet was associated with increased odds of overweight BMI (OR: 1.21; 95% CI: 1.02-1.44). Associations remained significant after FDR correction. Conclusions: Based on a cohort of US women designed to identify predictors of adverse pregnancy outcomes, dietary intake of combined EPA+DHA was considerably lower than recommended. Associations between intake of these recommended n-3 fatty acids and risk of PTB differ by maternal BMI.
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    Docosahexaenoic acid regulates the formation of lipid rafts: A unified view from experiment and simulation
    (Elsevier, 2018-10) Wassall, Stephen R.; Leng, Xiaoling; Canner, Samuel W.; Pennington, Edward Ross; Kinnun, Jacob J.; Cavazos, Andres T.; Dadoo, Sahil; Johnson, Dylan; Heberle, Frederick A.; Katsaras, John; Shaikh, Saame Raza; Physics, School of Science
    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.
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    Restoring retinal polyunsaturated fatty acid balance and retina function by targeting ceramide in AdipoR1-deficient mice
    (Elsevier, 2024) Lewandowski, Dominik; Gao, Fangyuan; Imanishi, Sanae; Tworak, Aleksander; Bassetto, Marco; Dong, Zhiqian; Pinto, Antonio F. M.; Tabaka, Marcin; Kiser, Philip D.; Imanishi, Yoshikazu; Skowronska-Krawczyk, Dorota; Palczewski, Krzysztof; Ophthalmology, School of Medicine
    Mutations in the adiponectin receptor 1 gene (AdipoR1) lead to retinitis pigmentosa and are associated with age-related macular degeneration. This study explores the effects of AdipoR1 gene deficiency in mice, revealing a striking decline in ω3 polyunsaturated fatty acids (PUFA), an increase in ω6 fatty acids, and elevated ceramides in the retina. The AdipoR1 deficiency impairs peroxisome proliferator-activated receptor α signaling, which is crucial for FA metabolism, particularly affecting proteins associated with FA transport and oxidation in the retina and retinal pigmented epithelium. Our lipidomic and proteomic analyses indicate changes that could affect membrane composition and viscosity through altered ω3 PUFA transport and synthesis, suggesting a potential influence of AdipoR1 on these properties. Furthermore, we noted a reduction in the Bardet-Biedl syndrome proteins, which are crucial for forming and maintaining photoreceptor outer segments that are PUFA-enriched ciliary structures. Diminution in Bardet-Biedl syndrome-proteins content combined with our electron microscopic observations raises the possibility that AdipoR1 deficiency might impair ciliary function. Treatment with inhibitors of ceramide synthesis led to substantial elevation of ω3 LC-PUFAs, alleviating photoreceptor degeneration and improving retinal function. These results serve as the proof of concept for a ceramide-targeted strategy to treat retinopathies linked to PUFA deficiency, including age-related macular degeneration.