Effects of administration of omega-3 fatty acids with or without vitamin E supplementation on adiponectin gene expression in PBMCs and serum adiponectin and adipocyte fatty acid-binding protein levels in male patients with CAD

Can vitamin E supplementation affect obesity indices? A systematic review and meta-analysis of twenty-four randomized controlled trials

BACKGROUND

Several mechanisms have been proposed for the effect of vitamin E on weight loss. Yet various interventional studies with wide ranges of doses and durations have reported contradictory results.

METHODS

Cochrane Library, PubMed, Scopus, and Embase databases were searched up to December 2020. Meta-analysis was performed using random-effect method. Effect size was presented as weighted mean difference (WMD) and 95% confidence interval (CI). Heterogeneity was evaluated using the I² index. In order to identification of potential sources of heterogeneity, predefined subgroup and meta regression analyses was conducted.

RESULTS

A total of 24 studies with 33 data sets were included. There was no significant effect of vitamin E on weight (WMD: 0.15, 95% CI: -1.35 to 1.65, P = 0.847), body mass index (BMI) (WMD = 0.04, 95% CI: -0.29 to 0.37, P = 0.815), and waist circumference (WC) (WMD = -0.19 kg, 95% CI: -2.06 to 1.68, P = 0.842), respectively. However, subgroup analysis revealed that vitamin E supplementation in studies conducted on participants with normal BMI (18.5-24.9) had increasing impact on BMI (P = 0.047).

CONCLUSION

There was no significant effect of vitamin E supplementation on weight, BMI and WC. However, vitamin E supplementation might be associated with increasing BMI in people with normal BMI (18.5-24.9).

Blood adipocytokine concentration in patients with peripheral artery disease

BACKGROUND

Inflammatory responses mediated by adipocytokines may affect both atherosclerosis development and progression, as well as the risk of in-stent restenosis. The aim of this study was to determine the relationships between blood leptin, adiponectin and tumor necrosis factor-α (TNF-α) concentrations and the 1-year outcome of superficial femoral artery (SFA) stenting.

METHODS

Blood concentrations of leptin, adiponectin and TNF-α were determined in 70 patients undergoing SFA stenting due to intermittent claudication and in 40 patients undergoing carotid artery stenting (CAS). All subjects were followed up for at least 1 year in relation to the occurrence of clinically driven target lesion revascularization (TLR) or a major adverse cardiovascular event (MACE).

RESULTS

Patients undergoing SFA stenting and CAS had similar blood adipocytokine concentrations. Patients with diabetes mellitus presented a higher leptin concentration, lower adiponectin-to-leptin ratio, and lower blood adiponectin concentration indexed to fat mass (FM) and to visceral adiposity score (VAS). In Kaplan-Meier analysis, blood concentration of TNF-α indexed to FM and to VAS was higher in patients who underwent TLR and MACE. However, in multifactorial analysis, the severity of atherosclerosis lesions in the femoropopliteal vascular region, estimated in relation to TASC-II classification, was the only predictor of TLR.

CONCLUSIONS

Circulating adipocytokines did not distinguish patients with different clinical manifestations of atherosclerosis. Higher ratios of TNF-α -to-FM and to VAS before SFA stenting were related to TLR and MACE occurrence. Dysregulation in adipocytokine secretion may be a potential mediator of a proatherogenic action of diabetes mellitus in patients with peripheral artery disease.

Effect of omega-3 fatty acid plus vitamin E Co-Supplementation on lipid profile: A systematic review and meta-analysis

BACKGROUND

Dyslipidemia is linked to chronic inflammation, which in return leads to a set of chronic disorders. Omega-3 fatty acids have been reported to reduce inflammation. Furthermore, Vitamin E is a fat-soluble vitamin which has antioxidant and anti-inflammatory effects. Vitamin E and omega-3 fatty acids co-supplementations may be more effective than the single supplementation in control dyslipidemia. Therefore, we designed and conducted the current systematic review and meta-analysis to investigate the effect of co-supplementation of vitamin E and omega-3 fatty acids on the lipid profile.

METHODS

A comprehensive search for studies published between January 1990 and July 2018 was performed. The initial search extracted 3015 potentially relevant articles. After studying these publications, 9 RCTs were potentially eligible and retrieved in full text.

RESULTS

The meta-analysis indicate that on total cholesterol, HDL, LDL and triglyceride individually did not show any significant difference between intervention and control groups, but vitamin E an omega-3 fatty acids co-supplementations significantly reduce VLDL levels.

CONCLUSIONS

Based on the available evidence, omega-3 fatty acid and vitamin E co-supplementation can reduce VLDL, although its effect on other lipid profile parameters requires more well-designed studies.

The Effects of Omega-3 and Vitamin E Co-supplementation on Carotid Intima-media Thickness and Inflammatory Factors in Patients with Polycystic Ovary Syndrome

Objectives

We sought to evaluate the effects of omega-3 and vitamin E co-supplementation on carotid intima-media thickness (CIMT) and inflammatory factors in patients with polycystic ovary syndrome (PCOS).

Methods

This randomized, double-blind, placebo-controlled trial was done among 60 women with PCOS. Participants were randomly assigned into two groups (n = 30 each group) and assigned to take either 1000 mg omega-3 plus 400 IU vitamin E supplements or a placebo for 12 weeks.

Results

Compared with placebo, omega-3 and vitamin E co-supplementation led to significant decreases in maximum levels of left CIMT (-0.006±0.006 vs. +0.002±0.007 mm, p < 0.001), mean levels of left CIMT (-0.005±0.006 vs. +0.002±0.010 mm, p = 0.010), maximum levels of right CIMT (-0.006±0.010 vs. +0.006±0.010 mm, p = 0.010), and mean levels of right CIMT (-0.005±0.005 vs. +0.001±0.010 mm, p = 0.020). Change in high-sensitivity C-reactive protein (hs-CRP) (-390.6±942.9 vs. +237.0±754.3 ng/mL, p = 0.006) was significantly different between the supplemented patients and placebo group. We did not observe any significant effect in plasma nitric oxide (NO) values following supplementation with omega-3 plus vitamin E compared with the placebo.

Conclusions

Co-supplementation with omega-3 and vitamin E for 12 weeks among patients with PCOS had beneficial effects on CIMT and serum hs-CRP values, but unchanged NO values.

The effects of omega-3 and vitamin E co-supplementation on parameters of mental health and gene expression related to insulin and inflammation in subjects with polycystic ovary syndrome

OBJECTIVE

The aim of this study was to evaluate the effects of omega-3 and vitamin E co-supplementation on parameters of mental health and gene expression related to insulin and inflammation in subjects with polycystic ovary syndrome (PCOS).

METHODS

Forty PCOS women were allocated into two groups and treated with 1000mg omega-3 fatty acids plus 400 IU vitamin E supplements (n = 20) or placebo (n = 20) per day for 12 weeks. Parameters of mental health were recorded at baseline and after the 12-week intervention. Gene expression related to insulin and inflammation were measured in blood samples of PCOS women.

RESULTS

After the 12-week intervention, compared with the placebo, omega-3 and vitamin E co-supplementation led to significant improvements in beck depression inventory total score (- 2.2 ± 2.0 vs. - 0.2 ± 1.3, P = 0.001), general health questionnaire scores (- 5.5 ± 4.6 vs. - 1.0 ± 2.3, P < 0.001) and depression anxiety and stress scale scores (- 7.2 ± 5.2 vs. - 1.3 ± 1.3, P < 0.001). Compared with the placebo, omega-3 and vitamin E co-supplementation could up-regulate peroxisome proliferator-activated receptor gamma (PPAR-γ) expression (P = 0.04) in peripheral blood mononuclear cells (PBMC) of PCOS women. In addition, compared with the placebo, omega-3 and vitamin E co-supplementation down-regulated interleukin-8 (IL-8) (P = 0.003) and tumor necrosis factor alpha (TNF-α) expression (P = 0.001) in PBMC of PCOS women. There were no significant difference between-group changes in glucose transporter 1 (GLUT-1), IL-6 and transforming growth factor beta (TGF-β) in PBMC of PCOS women.

CONCLUSION

Omega-3 and vitamin E co-supplementation was effective in improving parameters of mental health, and gene expression of PPAR-γ, IL-8 and TNF-α of women with PCOS.

Improved insulin sensitivity and lower postprandial triglyceride concentrations after cold-pressed turnip rapeseed oil compared to cream in patients with metabolic syndrome

BACKGROUND

The aim of this study was to compare acute effects of turnip rapeseed oil rich with mono- and polyunsaturated fatty acids and cream on postprandial triglyceride levels and post-glucose load measures of insulin sensitivity in population of men with metabolic syndrome.

METHODS

This open-label balanced crossover study included 37 men with metabolic syndrome. They underwent an oral glucose-fat tolerance test where they ingested 75 g of glucose with either 240 mL of cream or 84 mL of turnip rapeseed oil depending on the study arm. Hourly postprandial blood samples were drawn up to 5 h after this oral glucose-fat tolerance test to determine the changes in triglyceride concentrations and to measure insulin sensitivity. Changes in insulin sensitivity were calculated with different insulin sensitivity indices (OGIS, Stumvoll, Gutt and McAuley scores) derived from measured insulin and glucose concentrations. The oral glucose-fat tolerance test was preceded by a period during which the participants consumed a daily portion of either 35 mL of turnip rapeseed oil or 37.5 g of butter depending on the study arm in addition to their habitual diets. Both dietary periods lasted from 6 to 8 weeks. After an 8-week wash-out period the subjects crossed over to the other study arm and underwent the same process with the other fat adjunct.

RESULTS

The area under the curve for hourly triglyceride concentrations was 16% smaller after turnip rapeseed oil than after cream (13.86 [interquartile range 8.54] vs. 16.41 [9.09] mmol/l, p < 0.001). The insulin sensitivity markers of OGIS (324 [38.97] vs. 377 [68.38] p < 0.001), Stumvoll score (0.079 [0.029] vs. 0.085 [0.029], p = 0.038) and Gutt score (67.0 ± 2.78 vs. 78.8 ± 4.97 p = 0.001) were higher after turnip rapeseed oil period than after butter period. There was a non-significant change in the McAuley score.

CONCLUSION

Dietary turnip rapeseed oil improved postprandially measured insulin sensitivity and triglyceride concentrations compared to cream and butter. This provides a possible efficient dietary mean to treat cardiovascular risk factors.Trial registration ClinicalTrials.gov NCT01119690 (05-06-2010).

The effects of omega-3 fatty acids and vitamin E co-supplementation on gene expression of lipoprotein(a) and oxidized low-density lipoprotein, lipid profiles and biomarkers of oxidative stress in patients with polycystic ovary syndrome

This study was conducted to determine the effects of omega-3 fatty acids and vitamin E co-supplementation on gene expression of lipoprotein(a) (Lp[a]) and oxidized low-density lipoprotein (Ox-LDL), lipid profiles and biomarkers of oxidative stress in women with polycystic ovary syndrome (PCOS). This randomized double-blind, placebo-controlled trial was done on 68 women diagnosed with PCOS according to the Rotterdam criteria aged 18-40 years old. Participants were randomly assigned into two groups to receive either 1000 mg omega-3 fatty acids from flaxseed oil containing 400 mg α-Linolenic acid plus 400 IU vitamin E supplements (n = 34) or placebo (n = 34) for 12 weeks. Lp(a) and Ox-LDL mRNA levels were quantified in peripheral blood mononuclear cells of PCOS women with RT-PCR method. Lipid profiles and biomarkers of oxidative stress were quantified at the beginning of the study and after 12-week intervention. Quantitative results of RT-PCR demonstrated that compared with the placebo, omega-3 fatty acids and vitamin E co-supplementation downregulated expressed levels of Lp(a) mRNA (P < 0.001) and Ox-LDL mRNA (P < 0.001) in peripheral blood mononuclear cells of women with PCOS. In addition, compared to the placebo group, omega-3 fatty acids and vitamin E co-supplementation resulted in a significant decrease in serum triglycerides (-22.1 ± 22.3 vs. +7.7 ± 23.6 mg/dL, P < 0.001), VLDL- (-4.4 ± 4.5 vs. +1.5 ± 4.7 mg/dL, P < 0.001), total- (-20.3 ± 16.6 vs. +12.2 ± 26.1 mg/dL, P < 0.001), LDL- (-16.7 ± 15.3 vs. +11.9 ± 26.1 mg/dL, P < 0.001) and total-/HDL-cholesterol (-0.5 ± 0.6 vs. +0.4 ± 0.8, P < 0.001). There were a significant increase in plasma total antioxidant capacity (+89.4 ± 108.9 vs. +5.9 ± 116.2 mmol/L, P = 0.003) and a significant decrease in malondialdehyde levels (-0.3 ± 0.4 vs. -0.008 ± 0.6 μmol/L, P = 0.01) by combined omega-3 fatty acids and vitamin E intake compared with the placebo group. Overall, omega-3 fatty acids and vitamin E co-supplementation for 12 weeks in PCOS women significantly improved gene expression of Lp(a) and Ox-LDL, lipid profiles and biomarkers of oxidative stress.

A Randomized Controlled Clinical Trial Investigating the Effects of Omega-3 Fatty Acids and Vitamin E Co-Supplementation on Biomarkers of Oxidative Stress, Inflammation and Pregnancy Outcomes in Gestational Diabetes

OBJECTIVES

Limited data are available for assessing the effects of omega-3 fatty acids and vitamin E co-supplementation on metabolic profiles and pregnancy outcomes in gestational diabetes (GDM). This study was designed to determine the effects of omega-3 fatty acids and vitamin E co-supplementation on biomarkers of oxidative stress, inflammation and pregnancy outcomes in women with GDM.

METHODS

This randomized, double-blind, placebo-controlled clinical trial was conducted in 60 patients with GDM who were not taking oral hypoglycemic agents. Patients were randomly allocated to intake either 1000 mg omega-3 fatty acids from flaxseed oil plus 400 IU vitamin E supplements (n=30) or placebo (n=30) for 6 weeks. Fasting blood samples were obtained from the women at the beginning of the study and after the 6-week intervention to quantify related markers.

RESULTS

After 6 weeks of intervention, omega-3 fatty acids and vitamin E co-supplementation, compared with the placebo, resulted in a significant rise in total antioxidant capacity (TAC) (+187.5±224.9 vs. -32.5±136.1 mmol/L; p<0.001); nitric oxide (NO) (+5.0±7.7 vs. -12.0±28.0 µmol/L; p=0.002) and a significant decrease in plasma malondialdehyde (MDA) concentrations (-0.1±0.9 vs. +0.6±1.4 µmol/L; p=0.03). Co-supplementation with omega-3 fatty acids and vitamin E showed no detectable changes in plasma glutathione and serum high-sensitivity C-reactive protein levels. Joint omega-3 fatty acids and vitamin E supplementation resulted in lower incidences of hyperbilirubinemia in newborns (10.3% vs. 33.3%; p=0.03).

CONCLUSIONS

Overall, omega-3 fatty acids and vitamin E co-supplementation for 6 weeks in women with GDM had beneficial effects on plasma TAC, MDA and NO and on the incidence of the newborns' hyperbilirubinemia.

Effect of the omega-3 fatty acid plus vitamin E supplementation on subjective global assessment score, glucose metabolism, and lipid concentrations in chronic hemodialysis patients

SCOPE

This study was conducted to determine the effects of omega-3 fatty acid plus vitamin E supplementation on subjective global assessment (SGA) score and metabolic profiles in chronic hemodialysis (HD) patients.

METHODS AND RESULTS

This randomized double-blind placebo-controlled clinical trial was conducted among 120 chronic HD patients. Participants were randomly divided into four groups to receive: (i) 1250 mg/day omega-3 fatty acid containing 600 mg eicosapentaenoic acid and 300 mg docosahexaenoic acid + vitamin E placebo (n = 30), (ii) 400 IU/day vitamin E + omega-3 fatty acids placebo (n = 30), (iii) 1250 mg omega-3 fatty acids/day + 400 IU/day vitamin E (n = 30), and (iv) omega-3 fatty acids placebo + vitamin E placebo (n = 30) for 12 wk. Fasting blood samples were taken at baseline and after 12-wk intervention to measure metabolic profiles. Patients who received combined omega-3 fatty acids and vitamin E supplements compared with vitamin E, omega-3 fatty acids, and placebo had significantly decreased SGA score (p < 0.001), fasting plasma glucose (p = 0.01), serum insulin levels (p = 0.001), homeostasis model of assessment insulin resistance (p = 0.002), and improved quantitative insulin sensitivity check index (p = 0.006).

CONCLUSION

Omega-3 fatty acids plus vitamin E supplementation for 12 wk among HD patients had beneficial effects on SGA score and metabolic profiles.

Fasting and postprandial regulation of the intracellular localization of adiponectin and of adipokines secretion by dietary fat in rats

Background/Objective:

Dietary fat sources modulate fasting serum concentration of adipokines, particularly adiponectin. However, previous studies utilized obese animals in which adipose tissue function is severely altered. Thus, the present study aimed to assess the postprandial regulation of adipokine secretion in nonobese rats that consumed high-fat diet (HFD) composed of different types of fat for a short time.

Methods:

The rats were fed a control diet or a HFD containing coconut, safflower or soybean oil (rich in saturated fatty acid, monounsaturated fatty acid or polyunsaturated fatty acid, respectively) for 21 days. The serum concentrations of adiponectin, leptin, retinol, retinol-binding protein-4 (RBP-4), visfatin and resistin were determined at fasting and after refeeding. Adiponectin multimerization and intracellular localization, as well as the expression of endoplasmic reticulum (ER) chaperones and transcriptional regulators, were evaluated in epididymal white adipose tissue.

Results:

In HFD-fed rats, serum adiponectin was significantly decreased 30 min after refeeding. With coconut oil, all three multimeric forms were reduced; with safflower oil, only the high-molecular-weight (HMW) and medium-molecular-weight (MMW) forms were decreased; and with soybean oil, only the HMW form was diminished. These reductions were due not to modifications in mRNA abundance or adiponectin multimerization but rather to an increment in intracellular localization at the ER and plasma membrane. Thus, when rats consumed a HFD, the type of dietary fat differentially affected the abundance of endoplasmic reticulum resident protein 44 kDa (ERp44), sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor-γ (PPARγ) mRNAs, all of which are involved in the post-translational processing of adiponectin required for its secretion.

Leptin, RBP-4, resistin and visfatin serum concentrations did not change during fasting, whereas modest alterations were observed after refeeding.

Conclusions:

The short-term consumption of a HFD affected adiponectin localization in adipose tissue, thereby decreasing its secretion to a different magnitude depending on the dietary fat source. Evaluating the fasting serum concentration of adipokines was not sufficient to identify alterations in their secretion, whereas postprandial values provided additional information as dynamic indicators.