Increased Plasma Levels of Triglyceride-Enriched Lipoproteins Associate with Systemic Inflammation, Lipopolysaccharides, and Gut Dysbiosis in Common Variable Immunodeficiency.

PURPOSE: Triglycerides (TG) and their major transport lipoprotein in the circulation (VLDL) appear to be related to inflammation. Patients with common variable immunodeficiency (CVID) have inflammatory complications associated with gut microbial dysbiosis. We hypothesized that CVID patients have disturbed TG/VLDL profiles associated with these clinical characteristics. METHODS: We measured plasma concentrations of TGs, inflammatory markers, and lipopolysaccharide (LPS) in 95 CVID patients and 28 healthy controls. Additionally, in 40 CVID patients, we explored plasma lipoprotein profiling, fatty acid, gut microbial dysbiosis, and diet. RESULTS: TG levels were increased in CVID patients as compared to healthy controls (1.36 ± 0.53 mmol/l versus 1.08 ± 0.56 [mean, SD], respectively, P = 0.008), particularly in the clinical subgroup "Complications," characterized by autoimmunity and organ-specific inflammation, compared to "Infection only" (1.41 mmol/l, 0.71[median, IQR] versus [1.02 mmol/l, 0.50], P = 0.021). Lipoprotein profile analyses showed increased levels of all sizes of VLDL particles in CVID patients compared to controls. TG levels correlated positively with CRP (rho = 0.256, P = 0.015), IL-6 (rho = 0.237, P = 0.021), IL-12 (rho = 0.265, P = 0.009), LPS (r = 0.654, P = 6.59 × 10-13), CVID-specific gut dysbiosis index (r = 0.315, P = 0.048), and inversely with a favorable fatty acid profile (docosahexaenoic acid [rho = - 0.369, P = 0.021] and linoleic acid [rho = - 0.375, P = 0.019]). TGs and VLDL lipids did not appear to be associated with diet and there were no differences in body mass index (BMI) between CVID patients and controls. CONCLUSION: We found increased plasma levels of TGs and all sizes of VLDL particles, which were associated with systemic inflammation, LPS, and gut dysbiosis in CVID, but not diet or BMI.

Plasma methylmalonic acid predicts risk of acute myocardial infarction and mortality in patients with coronary heart disease: A prospective 2-cohort study.

BACKGROUND: Elevated plasma methylmalonic acid (MMA) is reported in patients with established coronary heart disease (CHD) and is considered a marker of vitamin B12 deficiency. Moreover, MMA-dependent reactions have been linked to alterations in mitochondrial energy metabolism and oxidative stress, key features in the pathophysiology of cardiovascular diseases (CVDs). OBJECTIVES: We examined whether plasma MMA prospectively predicted the long-term risk of acute myocardial infarction (AMI) and mortality. METHODS AND RESULTS: Using Cox modeling, we estimated hazard ratios (HRs) for endpoints according to per 1-SD increment of log-transformed plasma MMA in two independent populations: the Western Norway Coronary Angiography Cohort (WECAC) (patients evaluated for CHD; n = 4137) and the Norwegian Vitamin Trial (NORVIT) (patients hospitalized with AMI; n = 3525). In WECAC and NORVIT, 12.8% and 18.0% experienced an AMI, whereas 21.8% and 19.9% died, of whom 45.5% and 60.3% from CVD-related causes during follow-up (range 3-11 years), respectively. In WECAC, age- and gender-adjusted HRs (95% confidence interval) were 1.18 (1.09-1.28), 1.25 (1.18-1.33), and 1.28 (1.17-1.40) for future AMI, total mortality, and CVD mortality, respectively. Corresponding risk estimates were 1.19 (1.10-1.28), 1.22 (1.14-1.31), and 1.30 (1.19-1.42) in NORVIT. These estimates were only slightly attenuated after multivariable adjustments. Across both cohorts, the MMA-risk association was stronger in older adults, women, and non-smokers. CONCLUSIONS: Elevated MMA was associated with an increased risk of AMI and mortality in patients with suspected or verified CHD.

Altered Plasma Fatty Acids Associate with Gut Microbial Composition in Common Variable Immunodeficiency.

PURPOSE: Fatty acid (FA) abnormalities are found in various inflammatory disorders and have been related to disturbed gut microbiota. Patients with common variable immunodeficiency (CVID) have inflammatory complications associated with altered gut microbial composition. We hypothesized that there is an altered FA profile in CVID patients, related to gut microbial dysbiosis. METHODS: Plasma FAs were measured in 39 CVID patients and 30 healthy controls. Gut microbial profile, a food frequency questionnaire, and the effect of the oral antibiotic rifaximin were investigated in CVID patients. RESULTS: The n-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) (1.4 [1.0-1.8] vs. 1.9 [1.2-2.5], median (IQR), P < 0.05), and docosahexaenoic acid (DHA) (3.2 [2.4-3.9] vs. 3.5 [2.9-4.3], P < 0.05), all values expressed as weight percent of total plasma FAs, were reduced in CVID compared to controls. Also, n-6 PUFAs (34.3 ± 3.4 vs. 37.1 ± 2.8, mean ± SD, P < 0.001) and linoleic acid (LA) (24.5 ± 3.3 vs. 28.1 ± 2.7, P < 0.0001) and the FA anti-inflammatory index (98.9 [82.1-119.4] vs. 117.0 [88.7-153.1], median (IQR), P < 0.05) were reduced in CVID. The microbial alpha diversity was positively associated with plasma n-6 PUFAs (r = 0.41, P < 0.001) and LA (r = 0.51, P < 0.001), but not n-3 PUFAs (P = 0.78). Moreover, a 2-week course of rifaximin significantly reduced the proportion of n-6 PUFAs (P = 0.04, UNIANOVA). Serum immunoglobulin G (IgG) levels correlated with plasma n-3 PUFAs (rho = 0.36, P = 0.03) and DHA (rho = 0.41, P = 0.009). CONCLUSION: We found a potentially unfavorable FA profile in CVID, related to low IgG levels. High plasma n-6 PUFAs were related to increased gut microbial diversity and altered by rifaximin therapy.

Hepatic Energy Metabolism Underlying Differential Lipidomic Responses to High-Carbohydrate and High-Fat Diets in Male Wistar Rats.

BACKGROUND: Low-carbohydrate diets are suggested to exert metabolic benefits by reducing circulating triacylglycerol (TG) concentrations, possibly by enhancing mitochondrial activity. OBJECTIVE: We aimed to elucidate mechanisms by which dietary carbohydrate and fat differentially affect hepatic and circulating TG, and how these mechanisms relate to fatty acid composition. METHODS: Six-week-old, ∼300 g male Wistar rats were fed a high-carbohydrate, low-fat [HC; 61.3% of energy (E%) carbohydrate] or a low-carbohydrate, high-fat (HF; 63.5 E% fat) diet for 4 wk. Parameters of lipid metabolism and mitochondrial function were measured in plasma and liver, with fatty acid composition (GC), high-energy phosphates (HPLC), carnitine metabolites (HPLC-MS/MS), and hepatic gene expression (qPCR) as main outcomes. RESULTS: In HC-fed rats, plasma TG was double and hepatic TG 27% of that in HF-fed rats. The proportion of oleic acid (18:1n-9) was 60% higher after HF vs. HC feeding while the proportion of palmitoleic acid (16:1n-7) and vaccenic acid (18:1n-7), and estimated activities of stearoyl-CoA desaturase, SCD-16 (16:1n-7/16:0), and de novo lipogenesis (16:0/18:2n-6) were 1.5-7.5-fold in HC vs. HF-fed rats. Accordingly, hepatic expression of fatty acid synthase (Fasn) and acetyl-CoA carboxylase (Acaca/Acc) was strongly upregulated after HC feeding, accompanied with 8-fold higher FAS activity and doubled ACC activity. There were no differences in expression of liver-specific biomarkers of mitochondrial biogenesis and activity (Cytc, Tfam, Cpt1, Cpt2, Ucp2, Hmgcs2); concentrations of ATP, AMP, and energy charge; plasma carnitine/acylcarnitine metabolites; or peroxisomal fatty acid oxidation. CONCLUSIONS: In male Wistar rats, dietary carbohydrate was converted into specific fatty acids via hepatic lipogenesis, contributing to higher plasma TG and total fatty acids compared with high-fat feeding. In contrast, the high-fat, low-carbohydrate feeding increased hepatic fatty acid content, without affecting hepatic mitochondrial fatty acid oxidation.

A Randomized, Double-blind, Placebo-controlled Clinical Study to Investigate the efficacy of Herring Roe Oil for treatment of Psoriasis.

The effect of omega-3 polyunsaturated fatty acid supplements in patients with psoriasis vulgaris has previously been investigated, but interventions varied in source, composition, dose, administration route and duration of treatment. The observed beneficial effects in patients with psoriasis vulgaris using herring roe oil as a dietary supplement prompted this investigation. This randomised, double-blind and placebo-controlled study was designed and performed to explore the efficacy and safety of herring roe oil supplementation in 64 patients with plaque psoriasis (ClinicalTrials.gov: NCT03359577). The primary end-point was comparing the change in mean Psoriasis Area Severity Index (PASI) scores in the herring roe oil treatment group and the placebo group from baseline to week 26. In the intention-to-treat population, a statistically significant improvement in the mean PASI score was observed with herring roe oil compared to placebo at 26 weeks. In the recruited patient group, the measured improvement was greatest in patients with a PASI score from 5.5-9.9 at baseline.

Hepatic steatosis induced in C57BL/6 mice by a non-ß oxidizable fatty acid analogue is associated with reduced plasma kynurenine metabolites and a modified hepatic NAD+/NADH ratio.

BACKGROUND: Non-alcoholic fatty liver disease is often associated with obesity, insulin resistance, dyslipidemia, and the metabolic syndrome in addition to mitochondrial dysfunction and nicotinamide adenine dinucleotide (NAD+) deficiency. The aim of this study was to investigate how inhibition of mitochondrial fatty acid oxidation using the compound tetradecylthiopropionic acid (TTP) would affect hepatic triacylglycerol level and plasma levels of kynurenine (Kyn) metabolites and nicotinamide. METHODS: 12 C57BL/6 mice were fed a control diet, or an intervention diet supplemented with 0.9% (w/w) tetradecylthiopropionic acid for 14 days. Blood and liver samples were collected, enzyme activities and gene expression were analyzed in liver, in addition to fatty acid composition. Metabolites in the tryptophan/kynurenine pathway and total antioxidant status were measured in plasma. RESULTS: Dietary treatment with tetradecylthiopropionic acid for 2 weeks induced fatty liver accompanied by decreased mitochondrial fatty acid oxidation. The liver content of the oxidized form of NAD+ was increased, as well as the ratio of NAD+/NADH, and these changes were associated by increased hepatic mRNA levels of NAD synthetase and nicotinamide mononucleotide adenyltransferase-3. The downstream metabolites of kynurenine were reduced in plasma whereas the plasma nicotinamide content was increased. Some effects on inflammation and oxidative stress was observed in the liver, while the plasma antioxidant capacity was increased. This was accompanied by a reduced plasma ratio of kynurenine/tryptophan. In addition, a significant decrease in the inflammation-related arachidonic fatty acid in liver was observed. CONCLUSION: Fatty liver induced by short-time treatment with tetradecylthiopropionic acid decreased the levels of kynurenine metabolites but increased the plasma levels of NAD+ and nicotinamide. These changes are most likely not associated with increased inflammation and oxidative stress. Most probably the increase of NAD+ and nicotinamide are generated through the Preiss Handler pathway and/or salvage pathway and not through the de novo pathway. The take home message is that non-alcoholic fatty liver disease is associated with the metabolic syndrome in addition to mitochondrial dysfunction and nicotinamide adenine dinucleotide (NAD+) deficiency. Inducing fatty liver in mice by inhibition of fatty acid oxidation resulted in a concomitant change in kynurenine metabolites increasing the plasma levels of nicotinamides and the hepatic NAD+/NADH ratio, probably without affecting the de novo pathway of kynurenines.

Circulating gut microbiota metabolite trimethylamine N-oxide and oral contraceptive use in polycystic ovary syndrome.

OBJECTIVES: Polycystic ovary syndrome (PCOS) is associated with an increased cardiometabolic risk that might not necessarily translate into adverse cardiovascular outcome later in life. Recently, alterations in gut microbial composition have been reported in the syndrome. Microbiota-dependent metabolite trimethylamine N-oxide (TMAO) and its precursors are closely linked with development of atherosclerotic cardiovascular disease, independently of traditional risk factors. We aimed to assess whether TMAO and its precursors are altered in PCOS and to determine potential impact of treatment on these metabolites. DESIGN: Prospective study. PATIENTS: Twenty-seven overweight/obese patients with PCOS and 25 age- and BMI-matched healthy control women. MEASUREMENTS: At baseline, fasting serum TMAO and its precursors were measured after a 3-day standardized diet. Patients received 3-month OC therapy along with general dietary advice after which all measurements were repeated. RESULTS: Patients had higher total testosterone (T) and free androgen index (FAI) whereas whole-body fat mass, fasting plasma glucose, insulin and lipids were similar between the groups. PCOS group showed significantly higher serum levels of TMAO and its precursors; choline, betaine and carnitine. TMAO and choline showed correlations with T. After 3 months of OC use, TMAO and its precursors significantly decreased along with reductions in BMI, T and FAI. CONCLUSIONS: This study reports for the first time that TMAO and its precursors are elevated in PCOS which might contribute to increased cardiometabolic risk of the syndrome and that short-term OC use along with lifestyle intervention is associated with reduction of these microbiome-dependent metabolites.

One-Year Treatment with Olanzapine Depot in Female Rats: Metabolic Effects.

BACKGROUND: Antipsychotic drugs can negatively affect the metabolic status of patients, with olanzapine as one of the most potent drugs. While patients are often medicated for long time periods, experiments in rats typically run for 1 to 12 weeks, showing olanzapine-related weight gain and increased plasma lipid levels, with transcriptional upregulation of lipogenic genes in liver and adipose tissue. It remains unknown whether metabolic status will deteriorate with time. METHODS: To examine long-term metabolic effects, we administered intramuscular long-acting injections of olanzapine (100 mg/kg BW) or control substance to female rats for up to 13 months. RESULTS: Exposure to olanzapine long-acting injections led to rapid weight gain, which was sustained throughout the experiment. At 1, 6, and 13 months, plasma lipid levels were measured in separate cohorts of rats, displaying no increase. Hepatic transcription of lipid-related genes was transiently upregulated at 1 month. Glucose and insulin tolerance tests indicated insulin resistance in olanzapine-treated rats after 12 months. CONCLUSION: Our data show that the continuous increase in body weight in response to long-term olanzapine exposure was accompanied by surprisingly few concomitant changes in plasma lipids and lipogenic gene expression, suggesting that adaptive mechanisms are involved to reduce long-term metabolic adverse effects of this antipsychotic agent in rats.

Plasma choline, homocysteine and vitamin status in healthy adults supplemented with krill oil: a pilot study.

Plasma concentrations of metabolites along the choline oxidation and tryptophan degradation pathways have been linked to lifestyle diseases and dietary habits. This study aimed to investigate how krill oil, a source of ω-3 polyunsaturated fatty acids (PUFAs) with a high phosphatidylcholine content, affected these parameters. The pilot study was conducted as a 28 days intervention in 17 healthy volunteers (18-36 years), who received a supplement of 4.5 g krill oil per day, providing 833 mg ω-3 PUFAs, and 1750 mg phosphatidylcholine. Krill oil supplementation increased fasting plasma choline (+28.4%, p < .001), betaine (+26.6%, p < .001), dimethylglycine (+33.7%, p < .001) and sarcosine (+16.8%, p < .001), whereas no statistically significant changes were seen for plasma glycine, serine, methionine, total homocysteine, cysteine, cystathionine, methionine sulfoxide, folate, cobalamin, B2-, B3-, and B6 vitamers, tryptophan, kynurenines, nicotinamide, vitamin A and vitamin E. In summary, krill oil supplementation influenced choline metabolite levels, but not plasma metabolites of the tryptophan-kynurenine-nicotinamide pathways and vitamins. These observations should be confirmed in a placebo-controlled trial, including an ω-3 PUFA supplement without phospholipids to explore the potential additive effects of the different active ingredients.

Microbiota-dependent metabolite and cardiovascular disease marker trimethylamine-N-oxide (TMAO) is associated with monocyte activation but not platelet function in untreated HIV infection.

BACKGROUND: HIV infection is associated with increased risk of cardiovascular disease beyond that explained by traditional risk factors. Altered gut microbiota, microbial translocation, and immune activation have been proposed as potential triggers. The microbiota-dependent metabolite trimethylamine-N-oxide (TMAO) predicts myocardial infarction (MI) in the general population and has recently been shown to induce platelet hyperreactivity. In the present study, we investigated if TMAO was associated with platelet function, microbial translocation, and immune activation in both untreated and combination anti-retroviral therapy (cART) HIV infection. METHODS: TMAO and the pre-cursors betaine, choline, and carnitine were quantified by mass-spectrometry in plasma samples from a previously established cross-sectional cohort of 50 untreated and 50 cART treated HIV-infected individuals. Whole-blood impedance aggregometry, C-reactive protein, sCD14, and lipopolysaccharide were assessed as measures of platelet function, inflammation, monocyte activation, and microbial translocation, respectively. RESULTS: TMAO was not associated with platelet aggregation response after stimulation with four different agonists, or with overall hypo- or hyperreactivity in untreated or treated HIV-infected individuals. In contrast, sCD14 a marker of both monocyte activation and microbial translocation was independently associated with TMAO in untreated HIV-infection (R = 0.381, P = 0.008). Lower levels of carnitine [32.2 (28.4-36.8) vs. 38.2 (33.6-42.0), P = 0.001] and betaine [33.1 (27.3-43.4) vs.37.4 (31.5-48.7, P = 0.02], but similar TMAO levels [3.8 (2.3-6.1), vs. 2.9 µM (1.9-4.8) P = 0.15] were found in cART treated compared to untreated HIV-infected individuals, resulting in higher ratios of TMAO/carnitine [0.12 (0.07-0.20) vs. 0.08 (0.05-0.11), P = 0.02] and TMAO/betaine [0.11 (0.07-0.17) vs. 0.08 (0.05-0.13), P 0.02]. CONCLUSIONS: In contrast to recent studies in HIV-uninfected populations, the present study found no evidence of TMAO-induced platelet hyperreactivity in HIV infected individuals. Microbial translocation and monocyte activation may affect TMAO levels in untreated individuals. Furthermore, the elevated ratios of TMAO/betaine and TMAO/carnitine in cART-treated individuals could possibly suggest a role of cART in TMAO metabolism.

Bariatric surgery reduces fasting total fatty acids and increases n-3 polyunsaturated fatty acids in morbidly obese individuals.

BACKGROUND: Obesity is a global pandemic leading to increased mortality and increased risk of cardiovascular disease. Bariatric surgery is an established treatment of obesity leading to weight loss and reduction of mortality. To further elucidate how bariatric surgery improves metabolic control, we explored the fatty acid (FA) profiles in morbidly obese subjects treated with lifestyle intervention and subsequent bariatric surgery. METHODS: The intervention group consisted of 34 morbidly obese patients scheduled for bariatric surgery and the control group of 17 non-obese patients scheduled for elective laparoscopic procedures. The intervention group had to undergo lifestyle changes preoperatively. Fasting blood samples were drawn at admission, after lifestyle intervention and 1 year after bariatric surgery. RESULTS: At admission, the morbidly obese patients had significantly higher levels of monounsaturated FAs (MUFAs) and lower levels of n-6 polyunsaturated FAs (PUFAs) and n-3 PUFAs than healthy controls (all p-values <.05). In the intervention group, there was a significantly lower level of total FAs after lifestyle intervention, and from admission to 1 year after surgical intervention (both, p < .05), primarily reflecting a lower proportion of saturated FAs (SFAs). Following bariatric surgery, but not after lifestyle changes, there was an increase in the proportion of n-3 PUFA (p < .05) reaching levels not significantly different from healthy controls. CONCLUSIONS: Our findings suggest that a reduced proportion of the proposed anti-atherogenic n-3 PUFAs characterizes morbidly obese individuals, and that this FA profile is reversed by bariatric surgery, but not by lifestyle intervention.

Low levels of short- and medium-chain acylcarnitines in HIV-infected patients.

BACKGROUND: Carnitine plays an essential role in fatty acid metabolism, exerts substantial antioxidant action and regulates immune functions. We hypothesized that a disturbed carnitine metabolism could be involved in progression of HIV infection. MATERIALS AND METHODS: Plasma levels of L-carnitine, its precursors, and short-, medium- and long-chain acylcarnitines were analysed with HPLC/mass spectrometry in HIV-infected patients with various disease severities including patients who acquired Mycobacterium avium complex (MAC) infection. In vitro, we examined the MAC-purified protein derivate (PPD)-induced release of TNF-α and IFN-γ in peripheral blood mononuclear cells (PBMCs) from patients with either high or low plasma levels of acylcarnitines. RESULTS: Plasma levels of the short-chain (e.g. propionyl-carnitine) and medium-chain (e.g. octanoyl-carnitine) acylcarnitines were reduced in patients with advanced HIV infection. These acylcarnitines gradually decreased in rapid progressors, while minimal changes were observed in the nonprogressors. Plasma levels of propionyl-carnitine and octanoyl-carnitine significantly increased during antiretroviral therapy (ART). However, ART did not restore levels to those observed in healthy controls. Depletion of propionyl-carnitine and octanoyl-carnitine was observed prior to MAC infection, and the release of TNF-α and IFN-γ from PBMC was decreased after stimulation with MAC-PPD in samples from HIV-infected patients with low levels of propionyl-carnitine or octanoyl-carnitine. CONCLUSIONS: Our findings suggest an association between disturbed acylcarnitine metabolism, immune dysregulation and disease progression in HIV-infected patients. Low levels of propionyl-carnitine and octanoyl-carnitine were associated with increased susceptibility to MAC infection in HIV patients with advanced disease.

The molecular structure of thio-ether fatty acids influences PPAR-dependent regulation of lipid metabolism.

Thio-ether fatty acids (THEFAs), including the parent 2-(tetradecylthio)acetic acid (TTA), are modified fatty acids (FAs) that have profound effects on lipid metabolism given that they are blocked for ß-oxidation, and able to act as peroxisome proliferator-activated receptor (PPAR) agonists. Therefore, TTA in particular has been tested clinically for its therapeutic potential against metabolic syndrome related disorders. Here, we describe the preparation of THEFAs based on the TTA scaffold with either a double or a triple bond. These are tested in cultured human skeletal muscle cells (myotubes), either as free acid or following esterification as phospholipids, lysophospholipids or monoacylglycerols. Metabolic effects are assessed in terms of cellular bioavailabilities in myotubes, by FA substrate uptake and oxidation studies, and gene regulation studies with selected PPAR-regulated genes. We note that the inclusion of a triple bond promotes THEFA-mediated FA oxidation. Furthermore, esterification of THEFAs as lysophospholipids also promotes FA oxidation effects. Given that the apparent clinical benefits of TTA administration were offset by dose limitation and poor bioavailability, we discuss the possibility that a selection of our latest THEFAs and THEFA-containing lipids might be able to fulfill the therapeutic potential of the parent TTA while minimizing required doses for efficacy, side-effects and adverse reactions.

Serum trans fatty acids, asymmetric dimethylarginine and risk of acute myocardial infarction and mortality in patients with suspected coronary heart disease: a prospective cohort study.

BACKGROUND: Trans fatty acids (TFAs) have been found to impair flow mediated vasodilation and nitric oxide (NO) production. We sought to examine if serum TFA levels are associated with plasma levels of the NO inhibitor asymmetric dimethylarginine (ADMA) and if possible relationships between serum TFA and cardiovascular morbidity or mortality are mediated or modified by plasma ADMA levels. METHODS: The cohort included patients who underwent coronary angiography for suspected coronary heart disease in 2000-2001. Serum trans 16:1n7 and trans 18:1 isomers were determined by gas liquid chromatography and the summation of these two TFAs is reported as TFA (percentage by weight (wt%) or concentration). Associations between TFAs and ADMA were estimated by calculating the Spearman's rank correlation coefficient (ρ), and risk associations with AMI, cardiovascular death and all-cause mortality across quartiles of TFAs (wt% or concentration) were explored by Cox modeling. RESULTS: A total of 1364 patients (75 % men) with median (25(th),75(th) percentile) age 61 (54, 69) years, serum TFA 0.46 (0.36, 0.56) wt% and plasma ADMA 0.59 (0.50, 0.70) µmol/L were studied. Serum TFA levels (ρ = 0.21, p < 0.001), trans 16:1n7 (ρ = 0.22, p < 0.001) and trans 18:1 (ρ = 0.20, p < 0.001) levels were significantly correlated with plasma ADMA levels. During the median (25(th),75(th) percentile) follow-up time of 5.8 (4.5, 6.4) years, 129 (9.5 %) patients experienced an AMI, 124 (9.1 %) died, whereof 66 (53 %) due to cardiovascular causes. After multivariate adjustments no significant associations between serum TFA levels (wt% or concentration) and incident AMI, CV death and all-cause mortality were observed. Similar results were obtained when repeating the analyses with trans 16:1n7 and trans 18:1 individually. Plasma ADMA levels did not significantly modify the associations between TFA levels and outcomes. CONCLUSIONS: Serum TFA levels were positively correlated with plasma ADMA levels. After multivariate adjustments, TFAs were not associated with incident AMI or mortality, and associations were not influenced by ADMA. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT00354081.

Tetradecylthiopropionic acid induces hepatic mitochondrial dysfunction and steatosis, accompanied by increased plasma homocysteine in mice.

BACKGROUND: Hepatic mitochondrial dysfunction plays an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Methyl donor supplementation has been shown to alleviate NAFLD, connecting the condition to the one-carbon metabolism. Thus, the objective was to investigate regulation of homocysteine (Hcy) and metabolites along the choline oxidation pathway during induction of hepatic steatosis by the fatty acid analogue tetradecylthiopropionic acid (TTP), an inhibitor of mitochondrial fatty acid oxidation. METHODS: Mice were fed a control diet, or diets containing 0.3 %, 0.6 %, or 0.9 % (w/w) TTP for 14 days. Blood and liver samples were collected, enzyme activities and gene expression were analyzed in liver, lipid and fatty acid composition in liver and plasma, one-carbon metabolites, B-vitamin status, carnitine and acylcarnitines were analyzed in plasma. RESULTS: Liver mitochondrial fatty acid oxidation decreased by 40 % and steatosis was induced in a dose dependent manner; total lipids increased 1.6-fold in animals treated with 0.3 % TTP, 2-fold with 0.6 % TTP and 2.1 fold with 0.9 % TTP compared to control. The higher hepatic concentration of fatty acids was associated with shortening of carbon-length. Furthermore, the inhibited fatty acid oxidation led to a 30-fold decrease in plasma carnitine and 9.3-fold decrease in acetylcarnitine at the highest dose of TTP, whereas an accumulation of palmitoylcarnitine resulted. Compared to the control diet, TTP administration was associated with elevated plasma total Hcy (control: 7.2 ± 0.3 umol/L, 0.9 % TTP: 30.5 ± 5.9 umol/L) and 1.4-1.6 fold increase in the one-carbon metabolites betaine, dimethylglycine, sarcosine and glycine, accompanied by changes in gene expression of the different B-vitamin dependent pathways of Hcy and choline metabolism. A positive correlation between total Hcy and hepatic triacylglycerol resulted. CONCLUSIONS: The TTP-induced inhibition of mitochondrial fatty acid oxidation was not associated with increased hepatic oxidative stress or inflammation. Our data suggest a link between mitochondrial dysfunction and the methylation processes within the one-carbon metabolism in mice.

Altered Levels of Fatty Acids and Inflammatory and Metabolic Mediators in Epicardial Adipose Tissue in Patients With Systolic Heart Failure.

BACKGROUND: Adipose tissue has endocrine properties, secreting a wide range of mediators into the circulation, including factors involved in cardiovascular disease. However, little is known about the potential role of adipose tissue in heart failure (HF), and the aim of this study was to investigate epicardial (EAT) and subcutaneous (SAT) adipose tissue in HF patients. METHODS AND RESULTS: Thirty patients with systolic HF and 30 patients with normal systolic function undergoing thoracic surgery were included in the study. Plasma was sampled and examined with the use of enzyme-linked immunosorbent assays, whereas SAT and EAT biopsies were collected and examined by means of reverse-transcription polymerase chain reaction and gas chromatography. Significantly higher expressions of mRNA encoding interleukin-6, adrenomedullin, peroxisome proliferator-activated receptor α, and fatty acid (FA)-binding protein 3, as well as higher levels of monounsaturated FA and palmitoleic acid, were seen in the EAT of HF patients, whereas the levels of docosahexaenoic acid were lower. Palmitoleic acid levels in EAT were correlated with 2 parameters of cardiac remodeling: increasing left ventricular end-diastolic diameter and N-terminal pro-B-type natriuretic peptide. CONCLUSIONS: Our results demonstrate adipose tissue depot-specific alterations of synthesis of FA and inflammatory and metabolic mediators in systolic HF patients. EAT may be a source of increased circulatory and myocardial levels of these mediators through endocrine actions.

Hypolipidemic effect of dietary water-soluble protein extract from chicken: impact on genes regulating hepatic lipid and bile acid metabolism.

BACKGROUND: Amount and type of dietary protein have been shown to influence blood lipids. The present study aimed to evaluate the effects of a water-soluble fraction of chicken protein (CP) on plasma and hepatic lipid metabolism in normolipidemic rats. METHODS: Male Wistar rats were fed either a control diet with 20 % w/w casein as the protein source, or an experimental diet where casein was replaced with CP at 6, 14, or 20 % w/w for 4 weeks. RESULTS: Rats fed CP had markedly reduced levels of triacylglycerols (TAG) and cholesterol in both plasma and liver, accompanied by stimulated hepatic mitochondrial fatty acid oxidation and carnitine palmitoyltransferase 2 activity in the 20 % CP group compared to the control group. In addition, reduced activities and gene expression of hepatic enzymes involved in lipogenesis were observed. The gene expression of sterol regulatory element-binding transcription factor 1 was reduced in the 20 % CP-fed rats, whereas gene expression of peroxisome proliferator-activated receptor alpha was increased. Moreover, 6, 14, and 20 % CP-fed rats had significantly increased free carnitine and acylcarnitine plasma levels compared to control rats. The plasma methionine/glycine and lysine/arginine ratios were reduced in 20 % CP-treated rats. The mRNA level of ATP-binding cassette 4 was increased in the 20 % CP group, accompanied by the increased level of plasma bile acids. CONCLUSIONS: The present data suggest that the hypotriglyceridemic property of a water-soluble fraction of CP is primarily due to effects on TAG synthesis and mitochondrial fatty acid oxidation. The cholesterol-lowering effect by CP may be linked to increased bile acid formation.

Krill oil reduces plasma triacylglycerol level and improves related lipoprotein particle concentration, fatty acid composition and redox status in healthy young adults - a pilot study.

BACKGROUND: Lipid abnormalities, enhanced inflammation and oxidative stress seem to represent a vicious circle in atherogenesis, and therapeutic options directed against these processes seems like a reasonable approach in the management of atherosclerotic disorders. Krill oil (RIMFROST Sublime®) is a phospholipid-rich oil with eicosapentaenoic acid (EPA): docosahexaenoic acid (DHA) ratio of 1.8:1. In this pilot study we determined if krill oil could favourable affect plasma lipid parameters and parameters involved in the initiation and progression of atherosclerosis. METHODS: The study was conducted as a 28 days intervention study examining effect-parameters of dietary supplementation with krill oil (832.5 mg EPA and DHA per day). 17 healthy volunteers in the age group 18-36 (mean age 23 ± 4 years) participated. Plasma lipids, lipoprotein particle sizes, fatty acid composition in plasma and red blood cells (RBCs), plasma cytokines, antioxidant capacity, acylcarntines, carnitine, choline, betaine, and trimethylamine-N-oxide (TMAO) were measured before and after supplementation. RESULTS: Plasma triacylglycerol (TAG) and large very-low density lipoprotein (VLDL) & chylomicron particle concentrations decreased after 28 days of krill oil intake. A significant reduction in the TAG/HDL cholesterol resulted. Krill oil supplementation decreased n-6/n-3 polyunsaturated fatty acids (PUFA) ratio both in plasma and RBCs. This was due to increased EPA, DHA and docosapentaenoic acid (DPA) and reduced amount of arachidonic acid (AA). The increase of n-3 fatty acids and wt % of EPA and DHA in RBC was of smaller magnitude than found in plasma. Krill oil intake increased the antioxidant capacity, double bond index (DBI) and the fatty acid anti-inflammatory index. The plasma atherogenicity index remained constant whereas the thrombogenicity index decreased. Plasma choline, betaine and the carnitine precursor, γ-butyrobetaine were increased after krill oil supplementation whereas the TMAO and carnitine concentrations remained unchanged. CONCLUSION: Krill oil consumption is considered health beneficial as it decreases cardiovascular disease risk parameters through effects on plasma TAGs, lipoprotein particles, fatty acid profile, redox status and possible inflammation. Noteworthy, no adverse effects on plasma levels of TMAO and carnitine were found.

Fish oil and krill oil differentially modify the liver and brain lipidome when fed to mice.

BACKGROUND: Marine food is an important source of omega-3 fatty acids with beneficial health effects. Oils from marine organisms have different fatty acid composition and differ in their molecular composition. Fish oil (FO) has a high content of eicosapentaenoic and docosahexaenoic acids mainly esterified to triacylglycerols, while in krill oil (KO) these fatty acids are mainly esterified to phospholipids. The aim was to study the effects of these oils on the lipid content and fatty acid distribution in the various lipid classes in liver and brain of mice. METHODS: Mice were fed either a high-fat diet (HF), a HF diet supplemented with FO or with KO (n = 6). After six weeks of feeding, liver and brain lipid extracts were analysed using a shotgun and TAG lipidomics approach. Student t-test was performed after log-transformation to compare differences between study groups. RESULTS: Six weeks of feeding resulted in significant changes in the relative abundance of many lipid classes compared to control mice. In both FO and KO fed mice, the triacylglycerol content in the liver was more than doubled. The fatty acid distribution was affected by the oils in both liver and brain with a decrease in the abundance of 18:2 and 20:4, and an increase in 20:5 and 22:6 in both study groups. 18:2 decreased in all lipid classes in the FO group but with only minor changes in the KO group. Differences between the feeding groups were particularly evident in some of the minor lipid classes that are associated with inflammation and insulin resistance. Ceramides and diacylglycerols were decreased and cholesteryl esters increased in the liver of the KO group, while plasmalogens were decreased in the FO group. In the brain, diacylglycerols were decreased, more by KO than FO, while ceramides and lactosylceramides were increased, more by FO than KO. CONCLUSION: The changes in the hepatic sphingolipids and 20:4 fatty acid levels were greater in the KO compared to the FO fed mice, and are consistent with a hypothesis that krill oil will have a stronger anti-inflammatory action and enhances insulin sensitivity more potently than fish oil.

A Phospholipid-Protein Complex from Krill with Antioxidative and Immunomodulating Properties Reduced Plasma Triacylglycerol and Hepatic Lipogenesis in Rats.

Dietary intake of marine omega-3 polyunsaturated fatty acids (n-3 PUFAs) can change the plasma profile from atherogenic to cardioprotective. In addition, there is growing evidence that proteins of marine origin may have health benefits. We investigated a phospholipid-protein complex (PPC) from krill that is hypothesized to influence lipid metabolism, inflammation, and redox status. Male Wistar rats were fed a control diet (2% soy oil, 8% lard, 20% casein), or diets where corresponding amounts of casein and lard were replaced with PPC at 3%, 6%, or 11% (wt %), for four weeks. Dietary supplementation with PPC resulted in significantly lower levels of plasma triacylglycerols in the 11% PPC-fed group, probably due to reduced hepatic lipogenesis. Plasma cholesterol levels were also reduced at the highest dose of PPC. In addition, the plasma and liver content of n-3 PUFAs increased while n-6 PUFAs decreased. This was associated with increased total antioxidant capacity in plasma and increased liver gene expression of mitochondrial superoxide dismutase (Sod2). Finally, a reduced plasma level of the inflammatory mediator interleukin-2 (IL-2) was detected in the PPC-fed animals. The present data show that PPC has lipid-lowering effects in rats, and may modulate risk factors related to cardiovascular disease progression.