n-3 and n-6 Fatty acids are independently associated with lipoprotein-associated phospholipase A2 in the Multi-Ethnic Study of Atherosclerosis

Associations of ω-3, ω-6 polyunsaturated fatty acids intake and ω-6: ω-3 ratio with systemic immune and inflammatory biomarkers: NHANES 1999-2020

Background

In recent years, diseases caused by abnormal immune-inflammatory responses have become increasingly severe. Dietary intervention involving omega-3 polyunsaturated fatty acids (ω-3 PUFAs) has emerged as a potential treatment. However, research investigating the relationship between ω-3, ω-6 PUFAs, and ω-6 to ω-3 ratio with inflammatory biomarkers remains controversial.

Methods

To investigate the correlation between the intake of ω-3 and ω-6 PUFAs and the ratio of ω-6: ω-3 with biomarkers of inflammation, the National Health and Nutrition Examination Survey (NHANES) data (1999 to 2020) was utilized. The systemic immune-inflammation index (SII), platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR), and white blood cell (WBC) were selected as study subjects. Dietary data for ω-3 and ω-6 PUFAs were collected via two 24-h dietary recall interviews. SII index and other indicators were obtained from the blood routine data. The multiple linear regression and restricted cubic spline models were utilized to evaluate the association of ω-3, ω-6 PUFAs intake, and ω-6: ω-3 ratio to SII and secondary measures.

Results

This study involved a total of 43,155 American adults. ω-3 and ω-6 PUFAs exhibited negative correlations with SII, PLR, NLR, and WBC. The correlation between ω-6: ω-3 ratio and SII, PLR, NLR, and WBC was not significant. Furthermore, the dose-response relationship showed that the relationship between the intake of ω-3 and ω-6 PUFAs and SII was an "L" pattern.

Conclusion

Intake of dietary ω-3 and ω-6 PUFAs reduces the levels of several inflammatory biomarkers in the body and exerts immunomodulatory effects.

Increased sedentary time and decreased physical activity increases lipoprotein associated phospholipase A2 in obese individuals

BACKGROUND AND AIMS

Lipoprotein-associated Phospholipase A₂ (Lp-PLA₂) is a protein produced by inflammatory cells in circulation and is associated with cardiovascular disease (CVD) risk. Physical activity (PA) is known to reduce inflammation and risk for CVD. However, Lp-PLA₂ has yet to be examined in relation to PA and sedentary time. The purpose of this study was to determine if PA and sedentary time impacts Lp-PLA₂ mass. A total of 25 subjects with an average BMI of 30.6 ± 5.7 were included in the data analysis.

METHODS AND RESULTS

Data collected included anthropometric data, Lp-PLA₂ mass, peak oxygen uptake (VO₂peak), resting heart rate and blood pressure, obstructive sleep apnea (OSA) risk, and assessment of PA using an accelerometer. Sedentary minutes per day was positively associated with Lp-PLA₂ (r = 0.41, P < 0.05). Light intensity PA was negatively associated (r = -0.51. P = 0.01) with Lp-PLA₂. When subjects were divided into 2-quantiles by Lp-PLA₂, the group with the higher Lp-PLA₂ mass accumulated more sedentary time per day (P < 0.001) and less light intensity PA per day (P = 0.001). OSA risk and Lp-PLA₂ showed no relationship. Sedentary behavior was higher, and light intensity PA was lower in subjects with hiLp-PLA₂ mass. No difference was seen in moderate-to-vigorous intensity PA or steps per day.

CONCLUSIONS

This suggests that, total PA habits, including time spent sedentary and lower intensity PA, impacts the levels of Lp-PLA₂, an important inflammatory marker and marker of CVD risk.

Effects of flaxseed consumption on plasma lipids, lipoprotein-associated phospholipase A2 activity and gut microbiota composition in patients with coronary artery disease

Background: Clinical studies have demonstrated possible beneficial effects of flaxseed on cardiovascular disease risk factors, but limited studies have evaluated the effects of flaxseed on the plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) and gut microbial composition in patients with coronary artery disease (CAD). Aim: The purpose of the present study was to examine the effect of flaxseed consumption on plasma lipids and lipoproteins, Lp-PLA2 activity, as well as the relative abundance of some gut microbiota in CAD patients. Methods: In a randomized controlled parallel trial, 50 patients with CAD were randomly allocated to 12 weeks of supplementation of flaxseed (30 g/day) or control (usual care). Before and after the intervention, plasma lipids, Lp-PLA2 activity, and some gut microbiota composition (4 different bacterial genera, including Lactobacillus, Bifidobacteria, Bacteroidetes, Firmicutes) were measured. Results: Compared to control, flaxseed consumption was associated with improved Lp-PLA2 activity. After 12 weeks of intervention, no significant changes were observed in plasma lipids and fecal microbial composition in the two study groups. Conclusion: The present study showed that in patients with CAD, flaxseed supplementation reduced plasma Lp-PLA2 activity but had no effect on plasma lipids and the composition of some intestinal bacteria.

Associations between red blood cells fatty acids, desaturases indices and metabolism of platelet activating factor in healthy volunteers

INTRODUCTION

Platelet-activating-factor is an inflammatory lipid mediator. Key enzymes of its biosynthesis are CDP-choline:1-alkyl-2-acetyl-sn-glycerol-cholinephosphotransferase (PAF-CPT) and acetyl-CoA:lyso-PAF-acetyltransferases (Lyso-PAF-AT) while PAF-AH/Lp-PLA₂ degrade PAF. The interplay between PAF and fatty acids metabolism was explored.

MATERIAL AND METHODS

In a healthy population, PAF levels, its metabolic enzymes activity and RBC fatty acids were measured while desaturases indices (D) were estimated. A principal component analysis was also applied to assess patterns of RBC fatty acids.

RESULTS

SFA were related to increased PAF biosynthesis and decreased Lp-PLA₂ only in women. MUFA were inversely associated with PAF biosynthesis and positively with Lp-PLA₂. Omega-6 fatty acids were positively correlated only with PAF-CPT while no significant correlations were observed with n3 fatty acids. D6 index was positively related with PAF biosynthetic enzymes and inversely with Lp-PLA₂ while D9 correlated positively with Lp-PLA_2. The pattern of high MUFA and low n6 was associated with reduced PAF biosynthesis and/or increased catabolism in both sexes.

CONCLUSION

The role of fatty acids in amplifying or reducing inflammation seems to be also reflected in PAF metabolism.

Effects of canola or olive oil on plasma lipids, lipoprotein-associated phospholipase A2 and inflammatory cytokines in patients referred for coronary angiography

BACKGROUND

The potential cardioprotective benefits of olive oil (OO) and canola oil (CO) consumption have been shown in some studies. The present study compared the effects of CO and OO on plasma lipids, some inflammatory cytokines, and lipoprotein-associated phospholipase A₂ (Lp-PLA₂) mass and activity in patients undergoing coronary angiography.

METHODS

The current randomized, controlled, parallel-arm, clinical trial involved 48 patients (44 men and 4 women, aged 57.63 ± 6.34 years) with at least one classic cardiovascular risk factor (hypertension, dyslipidemia, or diabetes) who referred for coronary angiography. Patients were randomly divided into two groups and received 25 mL/day refined olive oil (n = 24) or canola oil (n = 24) for 6 weeks. Plasma lipids, some selected inflammatory markers, and Lp-PLA₂ levels were measured at baseline and after the intervention.

RESULTS

CO consumption produced a significant reduction in plasma Lp-PLA₂ mass (- 0.97 ± 1.84 vs. 0.34 ± 1.57 ng/mL, p = 0.008 for CO and OO, respectively), whereas the mean changes in interleukine-6 concentration were significantly lower after OO consumption compared with CO (- 9.46 ± 9.46 vs. -0.90 ± 6.80 pg/mL, p = 0.008 for OO and CO, respectively). After 6 weeks of intervention, no significant changes were observed in plasma Lp-PLA₂ activity, complement C3, C4, or lipid profiles in the two intervention groups.

CONCLUSIONS

Comparing the two vegetable oils in subjects with cardiovascular risk factors showed that the consumption of olive oil is more effective in reducing the level of inflammatory cytokine interleukine-6, whereas canola oil was more effective in lowering Lp-PLA₂ levels; however, this finding should be interpreted with caution, because Lp-PLA₂ activity did not change significantly.

TRIAL REGISTRATION

IRCT20160702028742N5 at www.irct.ir (04/19/2019).

Energy Intake and Plasma Adiponectin as Potential Determinants of Lipoprotein-Associated Phospholipase A2 Activity: A Cross-Sectional Study

Lipoprotein-associated phospholipase A₂ (Lp-PLA₂ ) is associated with increased risk of cardiovascular diseases (CVD) and type 2 diabetes mellitus. Lp-PLA₂ activity is positively associated with male sex, Caucasian race, the presence of metabolic syndrome (MetS) and low-density lipoprotein (LDL)-cholesterol, but it is negatively associated with high-density lipoprotein (HDL)-cholesterol. Associations with other cardiometabolic risk factors, inflammation markers, and lifestyle factors are few or inconsistent. We investigated potential determinants of Lp-PLA₂ activity among both nonmodifiable and modifiable CVD risk factors in a middle-aged Greek cohort without overt CVD. Two hundred eighty four subjects (159 men, 53 ± 9 years and 125 women 52 ± 9 years) participated in a cross-sectional study carried out during 2011-2012 in Athens, Attica. Cardiometabolic risk factors, inflammation markers, lifestyle factors, and Lp-PLA₂ activity were evaluated with established methods. The American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) criteria were used to define MetS. Lp-PLA₂ activity was not associated with MetS, but was associated with MetS components, markers of liver function, and macronutrient intake. Increased total energy intake was associated with increased Lp-PLA₂ activity (odds ratio, 95% confidence interval: 1.07, 1.01-1.14 and 1.10, 1.03-1.16 for the 4th and 3rd quartiles, respectively, compared to the 1st quartile) after adjustments for sex, pack-years of smoking, LDL-cholesterol, and statin treatment. Adiponectin tended to be inversely associated with Lp-PLA₂ activity (0.91, 0.82-1.00, and 4th versus 1st quartile). Our results suggested that total energy intake and adiponectin levels are potential determinants of Lp-PLA₂ activity.

Changes in the blood fatty-acid profile associated with oxidative-antioxidant disturbances in coronary atherosclerosis

Background

The objective of this work was to study the profile of fatty acids and to search for associations of fatty acids with oxidative-antioxidant parameters and an oxidative-inflammatory biomarker (lipoprotein-associated phospholipase A2) in men with coronary atherosclerosis and coronary heart disease.

Methods

Analysis of 20 fatty acids was performed in 60 men with angiographically confirmed coronary atherosclerosis and coronary heart disease and in a control group of men without coronary heart disease. Serum fatty-acid content was evaluated by high-performance gas-liquid chromatography. The blood levels of oxidative stress, total antioxidative defence, and lipoprotein-associated phospholipase 2 were analyzed.

Results

In the group of men with coronary atherosclerosis the levels of myristic and palmitic fatty acids were higher by 59% and 22%, respectively. An increase in the weight percentage of monounsaturated fatty acids was noted, such as palmitoleic, oleic, and octadecenic. Significantly lower levels of polyunsaturated fatty acids, such as linolic, eicosadienoic, eicosatrienoic, arachidonic, eicosapentaenoic, glinolenic, docosapentaenoic, and docosahexaenoic were detected in the group with coronary atherosclerosis. The lipoprotein-associated phospholipase A2 level was higher by 48%. Oxidative stress was higher by 17%, and the total antioxidant defence in serum was lower by 45%. We found correlations between fatty acids and oxidative-antioxidative alterations. The relative risk of vulnerable atherosclerotic plaques correlated with increased levels of palmitic, stearic, oleic, and linolic fatty acids.

Conclusions

Significant alterations in the profile of fatty acids are associated with oxidative-antioxidative alterations and are accompanied by an increase in free-radical formation, which can probably serve as a risk factor of atherosclerosis.

Biomarkers of Key Biological Pathways in CVD

This review provides background on the laboratory design for MESA (Multi-Ethnic Study of Atherosclerosis) as well as the approach used in MESA to select biomarkers for measurement. The research related to the multitude of circulating and urinary biomarkers of inflammation and other novel and emerging biological pathways in MESA is summarized by domain, or pathway, represented by the biomarker. The contributions of MESA biomarkers to our knowledge of these key pathways in the development and progression of atherosclerosis, cardiovascular disease, diabetes, kidney disease, and pulmonary disease are highlighted, as are the contributions of MESA to recommendations for clinical use of several of these biomarkers. In addition, contributions of MESA to multicohort genomics consortia and current collaborations in transomics and metabolomics are noted.

Impact of 8-week linoleic acid intake in soy oil on Lp-PLA2 activity in healthy adults

BACKGROUND

No intervention follow-up study has examined the association between plasma n-6 polyunsaturated fatty acids (PUFAs) and lipoprotein-associated phospholipase A₂ (Lp-PLA₂), which is a risk factor for cardiovascular disease (CVD). We aimed to determine whether the administration of linoleic acid (LA, 18:2n-6) in soy oil affected Lp-PLA₂ activity in healthy adults.

METHODS

Self-reported healthy participants (n = 150) were randomly assigned to three groups: a low LA group, in which 10 mL soy oil was replaced with one apple; a medium LA group, in which the typical food intake was maintained; and a high LA group, in which 1/3 cup of cooked refined rice was replaced with 9.9 g of soy oil capsules daily. Plasma fatty acids and Lp-PLA₂ activity were measured along with other CVD risk factors.

RESULTS

After 8 weeks of treatment, plasma LA levels decreased in the low LA group and increased in the high LA group. The high LA group showed greater increases in apolipoprotein B (apoB) and oxidized low-density lipoprotein (ox-LDL) than those in the low LA group. Plasma LA levels and Lp-PLA₂ activities demonstrated greater increases in the high LA group than those in the medium and low LA groups. Changes in plasma LA positively and independently correlated with changes in Lp-PLA₂ activity, which was negatively correlated with changes in collagen-epinephrine closure time (CEPI-CT).

CONCLUSIONS

An increase in plasma LA following intake of soy oil was independently associated with Lp-PLA₂ activity, which was also related to apoB, ox-LDL and CEPI-CT.

TRIAL REGISTRATION

ClinicalTrail.gov Identifier: NCT02753907, registered 25 April 2016 (retrospectively registered).

Effects of eicosapentaenoic acid and docosahexaenoic acid on cardiovascular disease risk factors: a randomized clinical trial

BACKGROUND

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the primary omega-3 fatty acids in fish oil, have been shown to reduce cardiovascular disease (CVD) risk.

OBJECTIVE

This study aimed to examine the independent effects of EPA and DHA on lipid and apolipoprotein levels, as well as on inflammatory biomarkers of CVD risk, using doses often used in the general population.

DESIGN

A blinded, randomized 6-week trial was performed in 121 healthy, normolipidemic subjects who received olive oil placebo 6g/d, EPA 600mg/d, EPA 1800mg/d, or DHA 600mg/d. The EPA was derived from genetically modified yeast.

RESULTS

The subjects tolerated the supplements well with no safety issues; and the expected treatment-specific increases in plasma EPA and DHA levels were observed. Compared to placebo, the DHA group had significant decreases in postprandial triglyceride (TG) concentrations (-20%, -52.2mg/dL, P=0.03), significant increases in fasting and postprandial low-density lipoprotein cholesterol (LDL-C) (+18.4%, 17.1mg/dL, P=0.001), with no significant changes in inflammatory biomarkers. No significant effects were observed in the EPA 600mg/d group. The high-dose EPA group had significant decreases in lipoprotein-associated phospholipase A2 concentrations (Lp-PLA₂) (-14.1%, -21.4ng/mL, P=0.003).

CONCLUSIONS

The beneficial effects of EPA 1800mg/d on CVD risk reduction may relate in part to the lowering of Lp-PLA₂ without adversely affecting LDL-C. In contrast, DHA decreased postprandial TG, but raised LDL-C. Our observations indicate that these dietary fatty acids have divergent effects on cardiovascular risk markers.

Red blood cell fatty acids and biomarkers of inflammation: a cross-sectional study in a community-based cohort

INTRODUCTION

Inflammation and inflammatory biomarkers have emerged as integral components and predictors of incident cardiovascular (CV) disease. Omega-3 fatty acids, particularly eicosapentaenoic and docosahexaenoic acids (EPA and DHA) have anti-inflammatory properties, and have been variably associated with lower blood pressure, favorable blood lipid changes, and reduced CV events.

METHODS AND RESULTS

We examined the cross-sectional association of red blood cell (RBC) fatty acids, representative of body membrane fatty acid composition, with 10 biomarkers active in multiple inflammatory pathways in 2724 participants (mean age 66 ± 9 years, 54% women, 8% minorities) from the Framingham Offspring and minority Omni Cohorts. After multivariable adjustment, the RBC EPA and DHA content was inversely correlated (all P ≤ 0.001) with 8 biomarkers: urinary isoprostanes (r = -0.16); and soluble interleukin-6 (r = -0.10); C-reactive protein (r = -0.08); tumor necrosis factor receptor 2 (r = -0.08); intercellular adhesion molecule-1 (r = -0.08); P-selectin (r = -0.06); lipoprotein-associated phospholipase-A2 mass (r = -0.11) and activity (r = -0.08). The correlations for monocyte chemoattractant protein-1 was -0.05, P = 0.006 and osteoprotegerin (r = -0.06, P = 0.002) were only nominally significant.

CONCLUSION

In our large community-based study, we observed modest inverse associations between several types of inflammatory biomarkers with RBC omega-3 fatty acid levels. Our findings are consistent with the hypothesis that omega-3 fatty acids have anti-inflammatory properties.