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Nutrition (Burbank, Los Angeles County,... Feb 2019Alpha-linolenic acid (ALA) and quercetin are characteristic compounds in plant-based diets. Cardioprotective effects have been described for both substances, although a... (Randomized Controlled Trial)
Randomized Controlled Trial
Effect of alpha-linolenic acid in combination with the flavonol quercetin on markers of cardiovascular disease risk in healthy, non-obese adults: A randomized, double-blinded placebo-controlled crossover trial.
OBJECTIVES
Alpha-linolenic acid (ALA) and quercetin are characteristic compounds in plant-based diets. Cardioprotective effects have been described for both substances, although a possible benefit of combining ALA and quercetin has not, to our knowledge, been evaluated yet. The aim of this study was to investigate the potential independent and additive effects of ALA and quercetin on blood pressure (BP) and lipid and glucose metabolism, as well as on biomarkers of inflammation, oxidative stress, and antioxidant status in healthy, non-obese men and women. Another aim was to examine whether chronic supplementation of supranutritional doses of quercetin would result in an accumulation of plasma quercetin concentration over time.
METHODS
In a double-blinded, placebo-controlled crossover trial, healthy volunteers were randomized to receive 3.6 g/d ALA plus 190 mg/d quercetin or placebo for 8 wk. Data from 67 individuals (34 men, 33 women, mean age: 24.6 y) were assessed.
RESULTS
Plasma quercetin, tamarixetin, isorhamnetin, and kaempferol increased significantly from baseline to study end with ALA + quercetin but not with ALA + placebo. No significant effect on office systolic BP, mean 24 h ambulatory BP (ABP), or mean daytime ABP was seen in either study group. Both interventions significantly decreased total cholesterol, low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B to a similar extent. No effect on high-density lipoprotein cholesterol, apolipoprotein A1, glucose, uric acid, oxidized low-density lipoprotein, C-reactive protein, or lipid-adjusted retinol, α-tocopherol, or β-carotene was seen in either group.
CONCLUSION
Although dietary supplements of 3.6 g/d ALA over an 8-wk period improved lipid profiles in healthy adults, antioxidative and oxidative status, inflammation, and BP remained unchanged. No evidence was seen for an additive or synergistic effect of ALA plus quercetin on markers of cardiovascular disease risk.
Topics: Adult; Biomarkers; Cardiovascular Diseases; Cross-Over Studies; Dietary Supplements; Double-Blind Method; Female; Humans; Male; Quercetin; Risk Factors; Young Adult; alpha-Linolenic Acid
PubMed: 30278429
DOI: 10.1016/j.nut.2018.06.012 -
The Journal of Nutrition Aug 2011The current literature suggests that linolenic acid biohydrogenation converts to stearic acid without the formation of CLA. However, a multitude of CLA were identified...
The current literature suggests that linolenic acid biohydrogenation converts to stearic acid without the formation of CLA. However, a multitude of CLA were identified in the rumen that are generally attributed to linoleic acid biohydrogenation. This study used a stable isotope tracer to investigate the biohydrogenation intermediates of (13)C-linolenic acid, including CLA. A continuous culture fermenter was used to maintain a mixed microbial population obtained from the rumen of cattle at pH 6.5 for 6 d. The mixed fermenter contents were then transferred to batch cultures containing either (13)C-labeled or unlabeled linolenic acid, which were run in triplicate for 0, 3, 24, and 48 h. The (13)C enrichment was determined by GC-MS. After 48 h of incubation, 8 CLA isomers were significantly enriched, suggesting that these CLA isomers originated directly from linolenic acid. The cis-10, cis-12 CLA isomer exhibited the highest enrichment (21.7%), followed by cis-9, cis-11 and trans-8, trans-10 CLA. The enrichment of these 2 CLA isomers ranged from 20.1 to 21.1% and the remaining 5 CLA including cis-9, trans-11 CLA were <15.0%. A multitude of nonconjugated and partially conjugated 18:2 and 18:3 isomers was enriched during the 48 h of incubation. The results of this study confirm that mixed ruminal microbes are capable of the formation of several CLA and 18:3 isomers from linolenic acid, indicating that linolenic acid biohydrogenation pathways are more complex than previously reported.
Topics: Animals; Cattle; Fermentation; Gas Chromatography-Mass Spectrometry; Hydrogen; Isomerism; Stearic Acids; alpha-Linolenic Acid
PubMed: 21653571
DOI: 10.3945/jn.111.138396 -
The American Journal of Clinical... Jun 2017The relation between α-linolenic acid (ALA), a plant-derived omega-3 (n-3) fatty acid, and age-related macular degeneration (AMD) is unclear. European researchers...
The relation between α-linolenic acid (ALA), a plant-derived omega-3 (n-3) fatty acid, and age-related macular degeneration (AMD) is unclear. European researchers reported that ≤40% of ALA can be present as forms. We aimed to evaluate the associations between intake of ALA and intermediate and advanced AMD. Seventy-five thousand eight hundred eighty-nine women from the Nurses' Health Study and 38,961 men from Health Professionals Follow-Up Study were followed up from 1984 to 2012 and from 1986 to 2010, respectively. We assessed dietary intake by a validated food-frequency questionnaire at baseline and every 4 y thereafter. One thousand five hundred eighty-nine incident intermediate and 1356 advanced AMD cases (primarily neovascular AMD) were confirmed by medical record review. The multivariable-adjusted HR for intermediate AMD comparing ALA intake at the top quintile to the bottom quintile was 1.28 (95% CI: 1.05, 1.56; -trend = 0.01) in the analyses combining 2 cohorts. The HR in each cohort was in the positive direction but reached statistical significance only in the women. However, the positive association was apparent only in the pre-2002 era in each cohort and not afterward (-time interaction = 0.003). ALA intake was not associated with advanced AMD in either time period. Using gas-liquid chromatography, we identified both ALA (mean ± SD: 0.13% ± 0.04%) and ALA isomers (0.05% ± 0.01%) in 395 erythrocyte samples collected in 1989-1990. In stepwise regression models, mayonnaise was the leading predictor of erythrocyte concentrations of ALA and one isomer of ALA. We also found ALA in mayonnaise samples. A high intake of ALA was associated with an increased risk of intermediate AMD before 2002 but not afterward. The period before 2002 coincides with the same time period when ALA was found in food and participants' blood; this finding deserves further study.
Topics: Aged; Diet; Erythrocytes; Feeding Behavior; Female; Humans; Macular Degeneration; Middle Aged; Risk Factors; Trans Fatty Acids; alpha-Linolenic Acid
PubMed: 28468892
DOI: 10.3945/ajcn.116.143453 -
Life Sciences Dec 2022Evolving type 2 diabetes (T2D) may influence locomotion and affective state, promoting metabolic dysfunction. We examined behaviour and neurobiology in a model of T2D,...
AIM
Evolving type 2 diabetes (T2D) may influence locomotion and affective state, promoting metabolic dysfunction. We examined behaviour and neurobiology in a model of T2D, testing for benefits with dietary n-3 polyunsaturated fatty acid (PUFA).
METHODS
Male C57Bl/6 mice received vehicle or 75 mg/kg streptozotocin (STZ) and 21 wks of control or Western diets (43 % fat, 40 % carbohydrate, 17 % protein). Sub-sets received dietary α-linolenic acid (ALA; 10 % of fat intake) for 6 wks. Behaviour was examined via open field and sucrose preference tests, and hippocampal and frontal cortex (FC) leptin and dopamine levels and inflammatory signalling assessed.
KEY FINDINGS
T2D mice exhibited weight gain (+15 %), hyperglycemia (+35 %), hyperinsulinemia (+60 %) and insulin-resistance (+80 % higher HOMA-IR), together with anxiety-like behaviour (without anhedonia) that appeared independent of body weight and glycemic status. Cortical leptin declined whereas receptor mRNA increased. Supplementation with ALA did not influence metabolic state, while enhancing locomotion and reducing anxiety-like behaviours in healthy but not T2D mice. Hippocampal dopamine was selectively increased by ALA in T2D mice, with a trend to reduced circulating leptin in both groups. Across all groups, anxiety-like behaviour was associated with declining cortical and hippocampal leptin levels and increasing receptor mRNA, while declining dopamine levels were accompanied by decreased dopamine/serotonin receptor transcripts.
SIGNIFICANCE
Chronic T2D induced anxiogenesis in mice appears to be independent of metabolic homeostasis but linked to central leptin-resistance, together with disturbed dopamine and serotonin signalling. Despite anxiolytic effects of ALA in healthy mice, no metabolic or behavioural benefits were evident in T2D.
Topics: Male; Mice; Animals; alpha-Linolenic Acid; Leptin; Diabetes Mellitus, Type 2; Diabetes Mellitus, Experimental; Neurobiology; Dopamine; Fatty Acids; Diet, Western; RNA, Messenger
PubMed: 36349604
DOI: 10.1016/j.lfs.2022.121137 -
Bioresource Technology Mar 2022Chlamydomonas reinhardtii grows fast and is rich in polyunsaturated fatty acids. To explore whether the alpha-linolenic acid (ALA) content can be further enhanced, the...
Chlamydomonas reinhardtii grows fast and is rich in polyunsaturated fatty acids. To explore whether the alpha-linolenic acid (ALA) content can be further enhanced, the cultures were incubated under different culture temperatures, light intensities and inoculum densities. Results showed that temperature exhibited more great impact on ALA synthesis of C. reinhardtii than light intensity and inoculum size. The changes of light intensity and inoculum size displayed non-significant effects on ALA content. The optimal ALA proportion in cells was obtained under the condition of 10 °C, 50 μE/m/s and 5% inoculum density, which reached ∼ 39%.The augmented initial inoculum density could markedly improve the biomass of C. reinhardtii under 10 °C. The maximum ALA productivity (16.42 mg/L/d) was gained under 10 °C coupled with 25% inoculum size, where higher intracellular sugar and protein yield were observed. These results suggest C. reinhardtii would be an alternative feedstock for the industrial production of ALA.
Topics: Biomass; Chlamydomonas reinhardtii; Cold Temperature; Temperature; alpha-Linolenic Acid
PubMed: 35065224
DOI: 10.1016/j.biortech.2022.126746 -
Analytica Chimica Acta Feb 2009This paper proposes an analytical method for simultaneous near-infrared (NIR) spectrometric determination of alpha-linolenic and linoleic acid in eight types of edible...
Determination of alpha-linolenic acid and linoleic acid in edible oils using near-infrared spectroscopy improved by wavelet transform and uninformative variable elimination.
This paper proposes an analytical method for simultaneous near-infrared (NIR) spectrometric determination of alpha-linolenic and linoleic acid in eight types of edible vegetable oils and their blending. For this purpose, a combination of spectral wavelength selection by wavelet transform (WT) and elimination of uninformative variables (UVE) was proposed to obtain simple partial least square (PLS) models based on a small subset of wavelengths. WT was firstly utilized to compress full NIR spectra which contain 1413 redundant variables, and 42 wavelet approximate coefficients were obtained. UVE was then carried out to further select the informative variables. Finally, 27 and 19 wavelet approximate coefficients were selected by UVE for alpha-linolenic and linoleic acid, respectively. The selected variables were used as inputs of PLS model. Due to original spectra were compressed, and irrelevant variables were eliminated, more parsimonious and efficient model based on WT-UVE was obtained compared with the conventional PLS model with full spectra data. The coefficient of determination (r(2)) and root mean square error prediction set (RMSEP) for prediction set were 0.9345 and 0.0123 for alpha-linolenic acid prediction by WT-UVE-PLS model. The r(2) and RMSEP were 0.9054, 0.0437 for linoleic acid prediction. The good performance showed a potential application using WT-UVE to select NIR effective variables. WT-UVE can both speed up the calculation and improve the predicted results. The results indicated that it was feasible to fast determine alpha-linolenic acid and linoleic acid content in edible oils using NIR spectroscopy.
Topics: Data Interpretation, Statistical; Least-Squares Analysis; Linoleic Acid; Plant Oils; Reproducibility of Results; Spectroscopy, Near-Infrared; alpha-Linolenic Acid
PubMed: 19185115
DOI: 10.1016/j.aca.2008.12.024 -
Journal of Dairy Science Mar 2017Oxylipids are derived from polyunsaturated fatty acids (PUFA) in cellular membranes and the relative abundance or balance may contribute to disease pathogenesis....
Oxylipids are derived from polyunsaturated fatty acids (PUFA) in cellular membranes and the relative abundance or balance may contribute to disease pathogenesis. Previous studies documented unique oxylipid profiles from cows with either coliform or Streptococcus uberis mastitis, suggesting that lipid mediator biosynthesis may be dependent on the type of microbial-derived agonist. Changing the fatty acid content of peripheral blood leukocytes also may be critical to the relative expression of oxylipid profiles and the outcome of bacterial infection. No information is available in dairy cows describing how changing cellular PUFA content will modify oxylipids in the context of a microbial agonist challenge. Therefore, the hypothesis for the current study was that PUFA supplementation would change bovine leukocyte fatty acid content and respective oxylipid profiles from ex vivo microbial agonist-challenged leukocytes. Fatty acid content of leukocytes and plasma was quantified in (1) samples from cows not supplemented with PUFA, (2) cows supplemented with linoleic acid (LnA), and (3) cows supplemented with α-linolenic acid (ALA). Plasma oxylipids were assessed after S. uberis or lipopolysaccharide exposure and was compared with unstimulated oxylipid profiles. Fatty acid supplementation with ALA significantly increased ALA content of blood leukocytes and plasma relative to LnA. Fatty acid supplementation affected several S. uberis-induced oxylipids, but only S. uberis-induced 15-oxoETE was greater with ALA supplementation compared with LnA. Notably, only LPS-induced 5,6 LXA was altered with fatty acid supplementation, but no significant effect of LnA vs. ALA treatment was identified. Future studies are needed to understand how leukocyte activation and membrane PUFA availability collectively contribute to differential oxylipid profiles.
Topics: Animals; Cattle; Eicosanoids; Fatty Acids; Fatty Acids, Unsaturated; Female; Linoleic Acid; alpha-Linolenic Acid
PubMed: 28109600
DOI: 10.3168/jds.2016-11599 -
The American Journal of Clinical... Jul 2006Human in vivo data on dietary determinants of alpha-linolenic acid (ALA; 18:3n-3) metabolism are scarce. (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND
Human in vivo data on dietary determinants of alpha-linolenic acid (ALA; 18:3n-3) metabolism are scarce.
OBJECTIVE
We examined whether intakes of ALA or linoleic acid (LA; 18:2n-6) or their ratio influences ALA metabolism.
DESIGN
During 4 wk, 29 subjects received a control diet (7% of energy from LA, 0.4% of energy from ALA, ALA-to-LA ratio = 1:19). For the next 6 wk, a control diet, a low-LA diet (3% of energy from LA, 0.4% of energy from ALA, ratio = 1:7), or a high-ALA diet (7% of energy from LA, 1.1% of energy from ALA, ratio = 1:7) was consumed. Ten days before the end of each dietary period, [U-13C]ALA was administered orally for 9 d. ALA oxidation was determined from breath. Conversion was estimated by using compartmental modeling of [13C]- and [12C]n-3 fatty acid concentrations in fasting plasma phospholipids.
RESULTS
Compared with the control group, ALA incorporation into phospholipids increased by 3.6% in the low-LA group (P = 0.012) and decreased by 8.0% in the high-ALA group (P < 0.001). In absolute amounts, it increased by 34.3 mg (P = 0.020) in the low-LA group but hardly changed in the high-ALA group. Nearly all ALA from the plasma phospholipid pool was converted into eicosapentaenoic acid. Conversion of eicosapentaenoic acid into docosapentaenoic acid and docosahexaenoic acid hardly changed in the 3 groups and was <0.1% of dietary ALA. In absolute amounts, it was unchanged in the low-LA group, but increased from 0.7 to 1.9 mg (P = 0.001) in the high-ALA group. ALA oxidation was unchanged by the dietary interventions.
CONCLUSION
The amounts of ALA and LA in the diet, but not their ratio, determine ALA conversion.
Topics: Breath Tests; Carbon Isotopes; Dose-Response Relationship, Drug; Double-Blind Method; Fatty Acids, Unsaturated; Female; Humans; Linoleic Acid; Male; Middle Aged; Oxidation-Reduction; Phospholipids; alpha-Linolenic Acid
PubMed: 16825680
DOI: 10.1093/ajcn/84.1.44 -
Haematologica Jun 2020Platelet adhesion to the sub-endothelial matrix and damaged endothelium occurs through a multi-step process mediated in the initial phase by glycoprotein Ib binding to...
Platelet adhesion to the sub-endothelial matrix and damaged endothelium occurs through a multi-step process mediated in the initial phase by glycoprotein Ib binding to von Willebrand factor (vWF), which leads to the subsequent formation of a platelet plug. The plant-derived ω-3 fatty acid α-linolenic acid is an abundant alternative to fish-derived n-3 fatty acids and has anti-inflammatory and antithrombotic properties. In this study, we investigated the impact of α-linolenic acid on human platelet binding to vWF under high-shear flow conditions (mimicking blood flow in stenosed arteries). Pre-incubation of fresh human blood from healthy donors with α-linolenic acid at dietary relevant concentrations reduced platelet binding and rolling on vWF-coated microchannels at a shear rate of 100 dyn/cm Depletion of membrane cholesterol by incubation of platelet-rich plasma with methyl-β cyclodextrin abrogated platelet rolling on vWF. Analysis of glycoprotein Ib by applying cryo-electron tomography to intact platelets revealed local clusters of glycoprotein Ib complexes upon exposure to shear force: the formation of these complexes could be prevented by treatment with α-linolenic acid. This study provides novel findings on the rapid local rearrangement of glycoprotein Ib complexes in response to high-shear flow and highlights the mechanism of inhibition of platelet binding to and rolling on vWF by α-linolenic acid.
Topics: Animals; Blood Platelets; Cluster Analysis; Electron Microscope Tomography; Humans; Platelet Glycoprotein GPIb-IX Complex; alpha-Linolenic Acid; von Willebrand Factor
PubMed: 31439672
DOI: 10.3324/haematol.2019.220988 -
The Journal of Nutrition Nov 2020Soybean lecithin, a plant-based emulsifier widely used in food, is capable of modulating postprandial lipid metabolism. With arising concerns of sustainability,...
BACKGROUND
Soybean lecithin, a plant-based emulsifier widely used in food, is capable of modulating postprandial lipid metabolism. With arising concerns of sustainability, alternative sources of vegetal lecithin are urgently needed, and their metabolic effects must be characterized.
OBJECTIVES
We evaluated the impact of increasing doses of rapeseed lecithin (RL), rich in essential α-linolenic acid (ALA), on postprandial lipid metabolism and ALA bioavailability in lymph-cannulated rats.
METHODS
Male Wistar rats (8 weeks old) undergoing a mesenteric lymph duct cannulation were intragastrically administered 1 g of an oil mixture containing 4% ALA and 0, 1, 3, 10, or 30% RL (5 groups). Lymph fractions were collected for 6 h. Lymph lipids and chylomicrons (CMs) were characterized. The expression of genes implicated in intestinal lipid metabolism was determined in the duodenum at 6 h. Data was analyzed using either sigmoidal or linear mixed-effects models, or one-way ANOVA, where appropriate.
RESULTS
RL dose-dependently increased the lymphatic recovery (AUC) of total lipids (1100 μg/mL·h per additional RL%; P = 0.010) and ALA (50 μg/mL·h per additional RL%; P = 0.0076). RL induced a faster appearance of ALA in lymph, as evidenced by the exponential decrease of the rate of appearance of ALA with RL (R2 = 0.26; P = 0.0064). Although the number of CMs was unaffected by RL, CM diameter was increased in the 30%-RL group, compared to the control group (0% RL), by 86% at 3-4 h (P = 0.065) and by 81% at 4-6 h (P = 0.0002) following administration. This increase was positively correlated with the duodenal mRNA expression of microsomal triglyceride transfer protein (Mttp; ρ= 0.63; P = 0.0052). The expression of Mttp and secretion-associated, ras-related GTPase 1 gene homolog B (Sar1b, CM secretion), carnitine palmitoyltransferase IA (Cpt1a) and acyl-coenzyme A oxidase 1 (Acox1, beta-oxidation), and fatty acid desaturase 2 (Fads2, bioconversion of ALA into long-chain n-3 PUFAs) were, respectively, 49%, 29%, 74%, 48%, and 55% higher in the 30%-RL group vs. the control group (P < 0.05).
CONCLUSIONS
In rats, RL enhanced lymphatic lipid output, as well as the rate of appearance of ALA, which may promote its subsequent bioavailability and metabolic fate.
Topics: Animals; Biological Availability; Brassica napus; Lecithins; Lipid Metabolism; Lymph; Rats; alpha-Linolenic Acid
PubMed: 32937654
DOI: 10.1093/jn/nxaa244