Showing papers in "Lipids in 2017"
TL;DR: This study investigated the possibility of modifying the fat content and the FA composition of yellow mealworms through feeding and how this would be influenced by developmental stages, pupal sex, and generation with the future aim of applying this coleopteran as a diet supplement for human health.
Abstract: Fat is the second most abundant component of the nutrient composition of the mealworm Tenebrio molitor (Coleoptera: Tenebrionidae) that represents also an interesting source of PUFA, especially n-6 and n-3 fatty acids, involved in prevention of cardiovascular diseases. This study investigated the possibility of modifying the fat content and the FA composition of yellow mealworms through feeding and how this would be influenced by developmental stages, pupal sex, and generation with the future aim of applying this coleopteran as a diet supplement for human health. Growth rate and cumulative mortality percentage on the different feeding substrates were also evaluated to select the optimal conditions for a mass-raising of this insect species. Despite the different fat content in the six different breeding substrates used, T. molitor larvae and pupae contained a constant fat percentage (>34% in larvae and >30% in pupae). A similar total fat content was found comparing larvae and male and female pupae of the second generation to those of the first generation. On the contrary, FA composition differed both in larvae and pupae reared on the different feeding substrates. However, the exemplars reared on the diets based on 100% bread and 100% oat flour showed SFA, PUFA percentages, and an n-6/n-3 ratio more suitable for human consumption; the diet based on beer yeast, wheat flour, and oat flour resulted in a contemporary diet that most satisfied the balance between a fat composition of high quality and favorable growth conditions.
80 citations
TL;DR: It is indicated that in a healthy population, consuming up to 3 eggs/day results in an overall beneficial effect on biomarkers associated with CVD risk, as documented by increased HDL-c, a reduced LDL-c/HDL-c ratio, and increased plasma choline in combination with no change in plasma LDL- c or TMAO concentrations.
Abstract: Eggs are a source of cholesterol and choline and may impact plasma lipids and trimethylamine-N-oxide (TMAO) concentrations, which are biomarkers for cardiovascular disease (CVD) risk. Therefore, the effects of increasing egg intake (0, 1, 2, and 3 eggs/day) on these and other CVD risk biomarkers were evaluated in a young, healthy population. Thirty-eight subjects [19 men/19 women, 24.1 ± 2.2 years, body mass index (BMI) 24.3 ± 2.5 kg/m2] participated in this 14-week crossover intervention. Participants underwent a 2-week washout with no egg consumption, followed by intake of 1, 2, and 3 eggs/day for 4 weeks each. Anthropometric data, blood pressure (BP), dietary records, and plasma biomarkers (lipids, glucose, choline, and TMAO) were measured during each intervention phase. BMI, waist circumference, systolic BP, plasma glucose, and plasma triacylglycerol did not change throughout the intervention. Diastolic BP decreased with egg intake (P < 0.05). Compared to 0 eggs/day, intake of 1 egg/day increased HDL cholesterol (HDL-c) (P < 0.05), and decreased LDL cholesterol (LDL-c) (P < 0.05) and the LDL-c/HDL-c ratio (P < 0.01). With intake of 2–3 eggs/day, these changes were maintained. Plasma choline increased dose-dependently with egg intake (P < 0.0001) while fasting plasma TMAO was unchanged. These results indicate that in a healthy population, consuming up to 3 eggs/day results in an overall beneficial effect on biomarkers associated with CVD risk, as documented by increased HDL-c, a reduced LDL-c/HDL-c ratio, and increased plasma choline in combination with no change in plasma LDL-c or TMAO concentrations.
71 citations
TL;DR: Prolonged deficiency in ATP production capacity underlies cell and tissue pathology that ultimately is manifest as dilated cardiomyopathy.
Abstract: The Barth syndrome (BTHS) is caused by an inborn error of metabolism that manifests characteristic phenotypic features including altered mitochondrial membrane phospholipids, lactic acidosis, organic acid-uria, skeletal muscle weakness and cardiomyopathy. The underlying cause of BTHS has been definitively traced to mutations in the tafazzin (TAZ) gene locus on chromosome X. TAZ encodes a phospholipid transacylase that promotes cardiolipin acyl chain remodeling. Absence of tafazzin activity results in cardiolipin molecular species heterogeneity, increased levels of monolysocardiolipin and lower cardiolipin abundance. In skeletal muscle and cardiac tissue mitochondria these alterations in cardiolipin perturb the inner membrane, compromising electron transport chain function and aerobic respiration. Decreased electron flow from fuel metabolism via NADH ubiquinone oxidoreductase activity leads to a buildup of NADH in the matrix space and product inhibition of key TCA cycle enzymes. As TCA cycle activity slows pyruvate generated by glycolysis is diverted to lactic acid. In turn, Cori cycle activity increases to supply muscle with glucose for continued ATP production. Acetyl CoA that is unable to enter the TCA cycle is diverted to organic acid waste products that are excreted in urine. Overall, reduced ATP production efficiency in BTHS is exacerbated under conditions of increased energy demand. Prolonged deficiency in ATP production capacity underlies cell and tissue pathology that ultimately is manifest as dilated cardiomyopathy.
68 citations
TL;DR: It is suggested that short-term high fat diet withdrawal can restore metabolic changes and prevent excess body weight gain, however, long-term dietary intervention may be required to optimize the restoration of gut microbiota in mouse.
Abstract: The gut microbiota is proposed as a “metabolic organ” involved in energy utilization and is associated with obesity. Dietary intervention is one of the approaches for obesity management. Changes in dietary components have significant impacts on host metabolism and gut microbiota. In the present study, we examined the influence of dietary fat intervention on the modification of gut mucosa-associated microbiota profile along with body weight and metabolic parameter changes. Male C57BL/6J mice (6-week old) were fed a low fat diet (10% kcal fat) as a control or a high fat diet (HFD 60% kcal fat) for 7 weeks. In another group, mice were fed HFD for 5 weeks followed by low fat control diet for 2 weeks (HFD + Control). At 7 weeks, body weight gain, blood glucose and hepatic triacylglycerol levels of mice fed a HFD were significantly higher than that of the control group and the HFD + Control group. There were significant differences in the diversity and predicted functional properties of microbiota in the cecum and colon mucosa between the control group and the HFD group. HFD feeding reduced the ratio of Bacteroidetes to Firmicutes, a microbiota pattern often associated with obesity. The HFD + Control diet partially restored the diversity and composition of microbiota in the cecum to the pattern observed in mice fed a control diet. These results suggest that short-term high fat diet withdrawal can restore metabolic changes and prevent excess body weight gain, however, long-term dietary intervention may be required to optimize the restoration of gut microbiota in mouse.
59 citations
TL;DR: Growing evidence suggests a complex interplay between n-3 and n-6 LCPUFA and the endocannabinoid system, suggesting an overlap in the neuroprotective effects observed with these different classes of lipids.
Abstract: The brain is enriched in arachidonic acid (ARA) and docosahexaenoic acid (DHA), long-chain polyunsaturated fatty acids (LCPUFAs) of the n-6 and n-3 series, respectively. Both are essential for optimal brain development and function. Dietary enrichment with DHA and other long-chain n-3 PUFA, such as eicosapentaenoic acid (EPA), has shown beneficial effects on learning and memory, neuroinflammatory processes, and synaptic plasticity and neurogenesis. ARA, DHA and EPA are precursors to a diverse repertoire of bioactive lipid mediators, including endocannabinoids. The endocannabinoid system comprises cannabinoid receptors, their endogenous ligands, the endocannabinoids, and their biosynthetic and degradation enzymes. Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are the most widely studied endocannabinoids and are both derived from phospholipid-bound ARA. The endocannabinoid system also has well-established roles in neuroinflammation, synaptic plasticity and neurogenesis, suggesting an overlap in the neuroprotective effects observed with these different classes of lipids. Indeed, growing evidence suggests a complex interplay between n-3 and n-6 LCPUFA and the endocannabinoid system. For example, long-term DHA and EPA supplementation reduces AEA and 2-AG levels, with reciprocal increases in levels of the analogous endocannabinoid-like DHA and EPA-derived molecules. This review summarises current evidence of this interplay and discusses the therapeutic potential for brain protection and repair.
59 citations
TL;DR: A mechanistic timeline from neutral lipid synthesis through lipid droplet formation and size augmentation to droplet breakdown is provided, demonstrating their vast roles in a number of cellular processes in both mitotic and post-mitotic cells.
Abstract: One of the most exciting areas of cell biology during the last decade has been the study of lipid droplets Lipid droplets allow cells to store non-polar molecules such as neutral lipids in specific compartments where they are sequestered from the aqueous environment of the cell yet can be accessed through regulated mechanisms These structures are highly conserved, appearing in organisms throughout the phylogenetic tree Until somewhat recently, lipid droplets were widely regarded as inert, however progress in the field has continued to demonstrate their vast roles in a number of cellular processes in both mitotic and post-mitotic cells No doubt the increase in the attention given to lipid droplet research is due to their central role in current pressing human diseases such as obesity, type-2 diabetes, and atherosclerosis This review provides a mechanistic timeline from neutral lipid synthesis through lipid droplet formation and size augmentation to droplet breakdown
52 citations
TL;DR: The results show that free fatty acids and cholesterol increased, whereas triglycerides and ergosterol decreased during the transition between promastigote to amastigotes, which indicates that development in the host depends on the internalization of the parasite.
Abstract: Leishmania sp., are trypanosomatid parasites that are phagocytized by human and animal macrophages. Transformation from the vector promastigote stage to the intracellular amastigote host cell stage is mandatory, since development in the host depends on the internalization of the parasite. We identified and analyzed the lipids involved in the promastigote to amastigote transformation process in the Leishmania donovani complex. Four lipid classes, phospholipids, free fatty acids, triglycerides and sterols were studied. The derivatization method of Bligh and Dyer was used to establish the fatty acid composition in each stage of the parasite. To stay within the context of Leishmania infection, we used amastigotes extracted from macrophages after experimental in vitro infection. The purification process was checked by electronic microscopy, the absence of major contamination by host-cell debris and a correct purification yield validated our experimental model. Our results show that free fatty acids and cholesterol increased, whereas triglycerides and ergosterol decreased during the transition between promastigotes to amastigotes. With respect to phospholipid classes, we found increased proportion of sphingomyelin and phosphatidylserine and lowered proportion of phosphatidylinositol and lysophosphatidylethanolamine. Regarding fatty acid composition, a significant increase of n-7 fatty acids was observed in amastigotes. Overall, the total n-6 fatty acids were decreased in PL. Several of the changes were also observed in TG and free fatty acids. Particularly, n-7 fatty acids and 20:4n-6 were highly increased, whereas n-9 fatty acid and n-6 precursors decreased.
44 citations
TL;DR: Assessment of n-3 fatty acid intake from foods and supplements in the US population found intake was highest in men aged 20 years or more, and lowest in children and women who are or may become pregnant and/or are lactating, among ethnicities.
Abstract: The American Heart Association recommends consuming fish (particularly oily fish) at least two times per week, which would provide ≈ 0.5 g/day of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) for cardiovascular disease risk reduction. Previous analyses indicate that this recommendation is not being met; however, few studies have assessed different ethnicities, subpopulations requiring additional n-3 fatty acid intake (i.e., children and pregnant and/or lactating women), or deciles of intake. Data from the National Health and Nutrition Examination Survey 2003–2008 was used to assess n-3 fatty acid intake from foods and supplements in the US population, according to age, sex, and ethnicity. A unique “EPA equivalents” factor, which accounts for potential conversion of shorter-chain n-3 fatty acids, was used to calculate total long-chain n-3 fatty acid intake. Data are reported for 24,621 individuals. More than 90% consumed less than the recommended 0.5 g/day from food sources (median = 0.11 g/day; mean = 0.17 g/day). Among the top 15% of n-3 fatty acid consumers, fish was the largest dietary contributor (71.2%). Intake was highest in men aged 20 years or more, and lowest in children and women who are or may become pregnant and/or are lactating. Among ethnicities, intake was lowest in Mexican-Americans. Only 6.2% of the total population reported n-3 fatty acid supplement use, and this did not alter median daily intake. Additional strategies are needed to increase awareness of health benefits (particularly among Mexican-Americans and women of childbearing age) and promote consumption of oily fish or alternative dietary sources to meet current recommendations.
42 citations
TL;DR: The evidence is not only supporting the modulatory effect of fat quality on obesity development but also presenting a number of interactions between obesity-related genes and the quality of dietary fat, which holds a promise for the possibility of using genetically targeted dietary interventions to reduce obesity risk in the future.
Abstract: The prevalence of obesity is skyrocketing worldwide. The scientific evidence has associated obesity risk with many independent factors including the quality of dietary fat and genetics. Dietary fat exists as the main focus of dietary guidelines targeting obesity reduction. To prevent/minimize the adipogenic effect of dietary fatty acids (FA), intakes of long-chain saturated- and trans-FA should be reduced and substituted with unsaturated FA. The optimal proportions of dietary unsaturated FA are yet to be defined, along with a particular emphasis on the need to achieve a balanced ratio of n-3:n-6 polyunsaturated FA and to increase monounsaturated FA consumption at the expense of saturated FA. However, inter-individual variability in weight loss in response to a dietary intervention is evident, which highlights the importance of exploring gene–nutrient interactions that can further modulate the risk for obesity development. The quality of dietary fat was found to modulate obesity development by interacting with genes involved in fatty acid metabolism, adipogenesis, and the endocannabinoid system. This review summarizes the current knowledge on the effect of the quality of dietary fat on obesity phenotype and obesity-related genes. The evidence is not only supporting the modulatory effect of fat quality on obesity development but also presenting a number of interactions between obesity-related genes and the quality of dietary fat. The identified gene–FA interaction may have a clinical importance and holds a promise for the possibility of using genetically targeted dietary interventions to reduce obesity risk in the future.
41 citations
TL;DR: Dietary PlsEtn, especially that with 22:6n-3 (docosahexaenoic acid, DHA), may ameliorate learning deficiencies in AD by altering lipid composition in the brain.
Abstract: Ethanolamine plasmalogen (PlsEtn), a major phospholipid in neuronal membranes [60–90 mol% of ethanolamine glycerophospholipid (EtnGpl)], is specifically decreased in brains from patients with Alzheimer’s disease (AD) The present study investigated how PlsEtn administration affects cognitive deficits and lipid composition in an animal model of AD AD model rats were infused with amyloid-β (Aβ) into the cerebral ventricle and divided into three groups Control, Egg, and Ascidian groups were then orally administered vehicle, egg yolk EtnGpl (260 μmol as EtnGpl/kg BW/day; 10 μmol as PlsEtn/kg BW/day), or ascidian viscera EtnGpl (260 μmol as EtnGpl/kg BW/day; 209 μmol as PlsEtn/kg BW/day), respectively After 4 weeks of dosing, Aβ-infused rats were tested for learning ability in an 8-arm radial maze The administration of ascidian viscera EtnGpl improved both reference and working memory-related learning abilities In lipid analysis, the Ascidian group showed higher levels of PlsEtn species in the plasma, erythrocytes, and liver when compared to other groups In addition, although there were no differences at levels of total plasmalogen including choline plasmalogen, the Ascidian group had significantly higher levels of 18:0ol/22:6-PlsEtn in the cerebral cortex These levels of 18:0ol/22:6-PlsEtn in the cerebral cortex were correlated with working memory-related learning ability Moreover, 18:0ol/22:6-PlsEtn levels in the cerebral cortex showed positive correlations with those in the erythrocytes and liver In summary, dietary PlsEtn, especially that with 22:6n-3 (docosahexaenoic acid, DHA), may ameliorate learning deficiencies in AD by altering lipid composition in the brain
40 citations
TL;DR: Overall, physiological and supraphysiological concentrations of TFA, especially tVA and tPA, prevented inflammatory gene expression in vitro, independent of PPAR-γ activation and may be due to an alteration of fatty acid metabolism in cell membranes caused by the high incorporation of T FA.
Abstract: Trans fatty acids (TFA) intake has been linked to cardiovascular diseases and liver diseases; yet the effect of TFA on inflammation remains controversial. Accordingly, the objective of this paper was to determine the in vitro effects of TFA on inflammatory gene expression. Human umbilical vein endothelial cells (HUVEC) and human hepatocellular carcinoma (HepG2) cells were treated for 24 h with either trans-vaccenic acid (tVA), trans-palmitoleic acid (tPA) or elaidic acid (EA) at concentrations of 5–150 µM, or with a mixture of tVA and tPA (150/50 µM). All TFA were highly incorporated into cell membranes, as determined by gas chromatography, representing 15–20% of total fatty acids in HUVEC and 3–8% in HepG2 cells. Incorporation of EA, a common industrial TFA, increased the ratio of the stearoyl-CoA desaturase (SCD-1), a key enzyme involved in fatty acid metabolism. Ruminant TFA, including tVA, tPA and the mixture of tVA and tPA, significantly reduced the TNF-α-induced gene expression of TNF, VCAM-1 and SOD2 in HUVEC, as well as TNF and IL-8 in HepG2 cells. EA also decreased inflammatory gene expression in HUVEC, but not in HepG2 cells. The inhibition of peroxisome proliferator-activated receptor (PPAR)-γ did not influence the effects of TFA on gene expression. Overall, physiological and supraphysiological concentrations of TFA, especially tVA and tPA, prevented inflammatory gene expression in vitro. This effect is independent of PPAR-γ activation and may be due to an alteration of fatty acid metabolism in cell membranes caused by the high incorporation of TFA.
TL;DR: Overall, flaxseed oil supplementation for 12 weeks in diabetic patients with CHD significantly improved gene expression levels of PPAR-γ, LP(a), IL-1 and TNF-α, but did not influence LDLR, IL-8 and TGF-β.
Abstract: This study was carried out to determine the effects of flaxseed oil administration on gene expression levels related to insulin, lipid and inflammation in overweight diabetic patients with coronary heart disease (CHD). This randomized double-blind, placebo-controlled trial was conducted among 60 diabetic patients with CHD. Subjects were randomly allocated into two groups to intake either 1000 mg n-3 fatty acid from flaxseed oil containing 400 mg α-Linolenic acid [ALA (18:3n-3)] (n = 30) or placebo (n = 30) twice a day for 12 weeks. Gene expression related to insulin, lipid and inflammation were quantified in peripheral blood mononuclear cells (PBMC) of diabetic patients with CHD with RT-PCR method. Results of RT-PCR demonstrated that after the 12-week intervention, compared with the placebo, flaxseed oil supplementation could up-regulate gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) (P = 0.02) in PBMC of diabetic patients with CHD. In addition, compared with the placebo, taking flaxseed oil supplements down-regulated gene expression levels of lipoprotein(a) [LP(a)] (P = 0.001), interleukin-1 (IL-1) (P = 0.001) and tumor necrosis factor alpha (TNF-α) (P = 0.02) in PBMC of diabetic patients with CHD. We did not observe any significant effect of flaxseed oil supplementation on gene expression levels of low-density lipoprotein receptor (LDLR), IL-8 and transforming growth factor beta (TGF-β) in PBMC of diabetic patients with CHD. Overall, flaxseed oil supplementation for 12 weeks in diabetic patients with CHD significantly improved gene expression levels of PPAR-γ, LP(a), IL-1 and TNF-α, but did not influence LDLR, IL-8 and TGF-β.
TL;DR: Daphnia FA composition was independent of that of the seston diet, indicating that Daphnia adjusted their storage lipids according to the physiological requirements of a given overwintering strategy.
Abstract: Diapause, which occurs through the production of dormant eggs, is a strategy used by some zooplankton to avoid winter months of persistent low temperatures and low food availability. However, reports of active zooplankton under the ice indicate that other strategies also exist. This study was aimed at evaluating whether the composition of storage lipids in the fall differs between diapausing and active overwintering Daphnia. We assessed the quantity of storage lipids and fatty acid (FA) composition of Daphnia species, along with FA content of seston, in six boreal, alpine and subarctic lakes at the onset of winter, and evaluated the association between storage lipids and Daphnia overwintering strategy. We found that active overwintering Daphnia had >55% body fat and the highest FA concentrations. Polyunsaturated FA, especially stearidonic acid (18:4n-3; SDA) and high ratios of n-3:n-6, were preferentially retained to a greater extent in active overwintering Daphnia than in those that entered diapause. Daphnia FA composition was independent of that of the seston diet, indicating that Daphnia adjusted their storage lipids according to the physiological requirements of a given overwintering strategy. The occurrence of an active overwintering strategy has consequences for zooplankton community structure, and can have important implications for the transfer of high-quality energy at higher trophic levels.
TL;DR: Functional characterization in yeast showed both Elovl4 enzymes have activity towards all the PUFA substrates assayed, and confirmed that C. gariepinus ElovL4 play important roles in the biosynthesis of very long-chain FA.
Abstract: Elongation of very long-chain fatty acid 4 (Elovl4) proteins participate in the biosynthesis of very long-chain (>C24) saturated and polyunsaturated fatty acids (FA). Previous studies have shown that fish possess two different forms of Elovl4, termed Elovl4a and Elovl4b. The present study aimed to characterize both molecularly and functionally two elovl4 cDNA from the African catfish Clarias gariepinus. The results confirmed that C. gariepinus possessed two elovl4-like elongases with high homology to two previously characterized Elovl4 from Danio rerio, and thus they were termed accordingly as Elovl4a and Elovl4b. The C. gariepinus Elovl4a and Elovl4b have open reading frames (ORF) of 945 and 915 base pairs, respectively, encoding putative proteins of 314 and 304 amino acids, respectively. Functional characterization in yeast showed both Elovl4 enzymes have activity towards all the PUFA substrates assayed (18:4n-3, 18:3n-6, 20:5n-3, 20:4n-6, 22:5n-3, 22:4n-6 and 22:6n-3), producing elongated products of up to C36. Moreover, the C. gariepinus Elovl4a and Elovl4b were able to elongate very long-chain saturated FA (VLC-SFA) as denoted by increased levels of 28:0 and longer FA in yeast transformed with elovl4 ORF compared to control yeast. These results confirmed that C. gariepinus Elovl4 play important roles in the biosynthesis of very long-chain FA. Tissue distribution analysis of elovl4 mRNAs showed both genes were widely expressed in all tissues analyzed, with high expression of elovl4a in pituitary and brain, whereas female gonad and pituitary had the highest expression levels for elovl4b.
TL;DR: FABP do not appear to be useful for determining disease severity or the effectiveness of antipsoriatic treatment, and FABP3 may be associated with inflammation or liver disorders in psoriatic patients.
Abstract: Psoriasis is associated with metabolic syndrome and cardiovascular disease. Fatty acid-binding proteins (FABP) have been recognized as predictors of these systemic disorders. The aim of this study was to assess correlations between levels of serum heart and adipocyte fatty acid-binding proteins (FABP3, FABP4) and disease severity, indicators of inflammation or metabolic disturbances, and topical treatment in psoriatic patients. Thirty-seven patients with relapse of plaque-type psoriasis and 16 healthy volunteers were recruited. Blood samples were collected before and after 14 days of therapy. Serum FABP concentrations were examined by enzyme-linked immunosorbent assay for correlation with Psoriasis Area and Severity Index (PASI), body mass index (BMI), inflammatory or metabolic parameters, and treatment used. The median FABP4 serum levels were significantly increased (p = 0.038) in psoriatic patients, while FABP3 levels did not differ (p = 0.47) compared to the controls. No significant correlations were noted between the proteins and PASI, C-reactive protein (CRP), BMI, or levels of glucose or lipids. FABP3 significantly correlated with white blood count (p = 0.03) and aspartate aminotransferase (p = 0.04). After topical treatment, there was no significant change in serum FABP3 [11.5 (4.9–30.3) vs. 12.9 (3.5–30.3) ng/ml] (p = 0.96), whereas FABP4 was decreased [27,286 (20,344–32,257) vs. 23,034 (18,320–29,874) pg/ml] (p = 0.12), losing its basal significance. FABP4 may be a marker of psoriasis, and FABP3 may be associated with inflammation or liver disorders in psoriatic patients. FABP do not appear to be useful for determining disease severity or the effectiveness of antipsoriatic treatment.
TL;DR: Inhibition of AMPK by compound C in CoFA-treated cardiomyocytes resulted in an increased expression of ADRP, FAT/CD36, and apoptosis to 183 ± 12%, revealing that AMPK activation plays an important role in prevention of palmitic acid-induced apoptosis and lipid accumulation in CARDIomyocytes.
Abstract: Palmitic acid, a main fatty acid (FA) in human nutrition, can induce apoptosis of cardiomyocytes. However, a specific combination of palmitic, myristic and palmitoleic acid (CoFA) has been reported to promote beneficial cardiac growth. The aim of this study was to investigate the relevance of CoFA for cardiac growth and to delineate the underlying signaling pathways of CoFA and palmitic acid treatment. CoFA treatment of C57Bl/6 mice increased FA serum concentrations. However, morphologic and echocardiographic analysis did not show myocardial hypertrophy. Cell culture studies using rat ventricular cardiomyocytes revealed an increased phosphorylation of AMP activated protein kinase α (AMPKα) to 155 ± 19% and its target acetyl-CoA-carboxylase to 177 ± 23% by CoFA. Treatment with myristic acid also increased AMPKα phosphorylation to 189 ± 32%. Palmitic acid did not activate AMPKα but increased expression of the FA translocase CD36 (FAT/CD36) to 163 ± 23% and adipose-differentiation-related-protein (ADRP), a sensitive marker of lipid accumulation, to 168 ± 42%. This was associated with an increased phosphorylation of the stress-activated-protein-kinase/Jun-amino-terminal-kinase (SAPK/JNK) to 173 ± 27%. In CoFA-treated cells, phosphorylation of SAPK/JNK was unaltered. FACS analysis revealed increased apoptosis to 159 ± 5% by palmitic acid but not by CoFA. AMPK activator AICAR (5-aminoimidazole-4-carboxamide ribonucleotide) prevented up-regulation of ADRP and increased apoptosis by palmitic acid. Confirming these findings, inhibition of AMPK by compound C in CoFA-treated cardiomyocytes resulted in an increased expression of ADRP to 154 ± 27%, FAT/CD36 to 167 ± 28% and apoptosis to 183 ± 12%. These data reveal that AMPK activation plays an important role in prevention of palmitic acid-induced apoptosis and lipid accumulation in cardiomyocytes.
TL;DR: Evidence is presented that BSCL2/Bscl2 plays a role in lipid droplet (LD) biogenesis and homeostasis in primary and cultured hepatocytes, and it is suggested that a hepatic BSCL/Bscl2 deficiency induces the increase and expansion of LD, potentially via increased SCD1 activity.
Abstract: Berardinelli-Seip congenital lipodystrophy (BSCL) is an autosomal recessive disorder. The more severe form, designated BSCL2, arises due to mutations in the BSCL2 gene. Patients with BSCL2, as well as Bscl2
−/− mice, have a near total absence of body fat, an organomegaly, and develop metabolic disorders including insulin resistance and hepatic steatosis. The function of the Seipin (BSCL2) protein remains poorly understood. Several lines of evidence have indicated that Seipin may have distinct functions in adipose versus non-adipose cells. Here we present evidence that BSCL2/Bscl2 plays a role in lipid droplet (LD) biogenesis and homeostasis in primary and cultured hepatocytes. Our results show that decreasing BSCL2/Bscl2 expression in hepatocytes increases the number and size of LD, as well as the expression of genes implicated in their formation and stability. We also show that knocking down SCD1 expression reverses the phenotype associated with Seipin deficiency. Interestingly, BSCL2 knockdown induces SCD1 expression and activity, potentially leading to increased basal phosphorylation of proteins involved in the insulin signaling cascade, as well as further increasing fatty acid uptake and de novo lipogenesis. In conclusion, our results suggest that a hepatic BSCL2/Bscl2 deficiency induces the increase and expansion of LD, potentially via increased SCD1 activity.
TL;DR: The above result indicates that the hydrolysis mechanism of PL during seafood storage was correlated to the lipid hydrolytic enzyme activities under different storage temperatures.
Abstract: A fast and efficient shotgun lipidomics strategy was applied to analyze phospholipids (PL) in the oyster Crassostrea plicatula, including 29 species of phosphatidylcholine (PtdCho), 23 species of phosphatidylethanolamine (PtdEtn), 11 species of phosphatidylserine (PtdSer), 6 species of phosphatidylinositol (PtdIns), and 17 species of lysophospholipids (Lyso-PL). During storage at 4 °C for 7 days, the PL content decreased by 68.08%, but a significant increase in the FFA content was observed (from 63.11 to 318.72 μg/g). PtdCho and PtdIns decreased relatively by 64.97 and 67.49%, and PtdSer decreased most markedly by 74.15%. However, the PtdEtn content increased slightly during the early stages of storage but subsequently began to decrease. Moreover, PL with eicosapentaenoic acid (EPA-PL) and docosahexaenoic acid (DHA-PL) decreased by 51.77 and 50.61%, whereas plasmalogens were relatively stable showing only a 25.46% decrease. In particular, through enzyme activity analysis of lipase, phospholipase A1 (PLA1), phospholipase A2 (PLA2), phospholipase C (PLC), and phospholipase D (PLD), it was observed that the activities of all these enzymes increased at the early stage at 4 °C, but their activities were at lower levels when the oysters were stored at −20 °C. During the storage period at 4 °C, correlation analysis suggests that the degradation of PtdCho was mostly correlated to PLA2 (p < 0.05), whereas PtdEtn and PtdSer were more markedly correlated to lipase and PLD, respectively. The above result indicates that the hydrolysis mechanism of PL during seafood storage was correlated to the lipid hydrolytic enzyme activities under different storage temperatures.
TL;DR: Co-administration of l-carnitine with simvastatin was associated with a significant, albeit modest, reduction in Lp(a) compared with simVastatin monotherapy in subjects with mixed hyperlipidemia and elevated baseline Lp (a) levels.
Abstract: Lipoprotein (a) [Lp(a)] is an independent risk factor for cardiovascular disease. There are currently limited therapeutic options to lower Lp(a) levels. l-Carnitine has been reported to reduce Lp(a) levels. The aim of this study was to compare the effect of l-carnitine/simvastatin co-administration with that of simvastatin monotherapy on Lp(a) levels in subjects with mixed hyperlipidemia and elevated Lp(a) concentration. Subjects with levels of low-density lipoprotein cholesterol (LDL-C) >160 mg/dL, triacylglycerol (TAG) >150 mg/dL and Lp(a) >20 mg/dL were included in this study. Subjects were randomly allocated to receive l-carnitine 2 g/day plus simvastatin 20 mg/day (N = 29) or placebo plus simvastatin 20 mg/day (N = 29) for a total of 12 weeks. Lp(a) was significantly reduced in the l-carnitine/simvastatin group [−19.4%, from 52 (20–171) to 42 (15–102) mg/dL; p = 0.01], but not in the placebo/simvastatin group [−6.7%, from 56 (26–108) to 52 (27–93) mg/dL, p = NS versus baseline and p = 0.016 for the comparison between groups]. Similar significant reductions in total cholesterol, LDL-C, apolipoprotein (apo) B and TAG were observed in both groups. Co-administration of l-carnitine with simvastatin was associated with a significant, albeit modest, reduction in Lp(a) compared with simvastatin monotherapy in subjects with mixed hyperlipidemia and elevated baseline Lp(a) levels.
TL;DR: The unique characteristics of novel lipase Lip256, including its thermo-alkaliphilic performance, high tolerance toward metal ions, inhibitors, and detergents, and high stability in organic solvents, implied that this enzyme might be an interesting candidate for industrial processes.
Abstract: A novel lipase gene lip256 was cloned and identified from the genomic library of hot spring strain Bacillus sp HT19 The deduced amino acid sequence of lip256 has less than 32% identity to a predicted esterase (Cog1752) from Photobacterium leiognathi lrivu41 and contains a novel motif (GTSAG) that differs from other clusters in the lipase superfamily Following purification, a single band was obtained with a molecular mass of 33 kDa by SDS-PAGE, and the optimal temperature and pH for lipolytic activity of Lip25 were 70 °C and 90, respectively Lip256 exhibited high activity at high temperatures, with 40% maximum activity at 80 °C and good stability at temperatures ranges between 50 and 80 °C Additionally, the enzyme was highly stable in the presence of butyl-alcohol, glycerol, acetonitrile, pyridine, and urea However, the presence of acetone, methanol, trichloromethane, petroleum ether, hexane, tert-butanol, isopropanol, dithiothreitol, ethylenediaminetetraacetic acid, polyhexamethylene biguanide, dimethyl sulfoxide, benzene, Triton X-100, Tween-20, Tween-80, and sodium dodecyl sulfate suppressed or absolutely inhibited enzyme activity Furthermore, Ca2+, Mg2+, and Cu2+ suppressed enzyme activity, whereas Na+, Fe3+, K+, Fe2+, and Sr2+ enhanced enzyme activity The unique characteristics of novel lipase Lip256, including its thermo-alkaliphilic performance, high tolerance toward metal ions, inhibitors, and detergents, and high stability in organic solvents, implied that this enzyme might be an interesting candidate for industrial processes
TL;DR: Dietary c9t11 may be an effective adjunct to COX-2 inhibition for treating chronic inflammation and paw and plasma IL-10 levels in arthritic mice were decreased by 5 mg/kg celecoxib, but were unaffected by c9T11 compared to CO.
Abstract: Cyclooxygenase (COX)-2 inhibitors, such as celecoxib, for chronic inflammatory disease are associated with adverse health events, while cis-9, trans-11 (c9t11) conjugated linoleic acid (CLA) is anti-inflammatory without adverse events attributed to pure intake. Mechanistically, celecoxib and c9t11 disrupt the arachidonic acid cascade; however, the equivalency of anti-inflammatory effects between these compounds is unknown. Therefore, to test the hypothesis that 0.5% dietary c9t11 reduces inflammation equivalently to a celecoxib dose intended to treat rheumatoid arthritis (RA; 5 mg/kg bw), arthritic mice received diets containing one of the following supplements: 1% corn oil (CO, w/w), 0.5% c9t11 (>91% purity) +0.5% CO, or 1% CO + 0.5, 5, or 50 mg/kg bw celecoxib, and were assessed for changes in arthritic severity over 6 weeks. Overall, arthritic severity in mice fed c9t11 was reduced (34%, P < 0.01) while celecoxib doses (0.5, 5, 50 mg/kg) reduced arthritic severity (16, 56, 48%, respectively) compared to CO-fed arthritic mice. Linear regression of the celecoxib dose-response showed 0.5% c9t11 (570 mg/kg bw) reduced arthritic severity equivalently to 1.5 mg/kg celecoxib. Interleukin-6 (IL-6) was increased in paws of arthritic mice fed CO compared to shams, but was decreased in arthritic groups fed 0.5% c9t11 and 5 mg/kg celecoxib, compared to arthritic mice fed CO (Ps ≤ 0.05). Additionally, paw and plasma IL-10 levels in arthritic mice were decreased by 5 mg/kg celecoxib, but were unaffected by c9t11 compared to CO. Results suggest dietary c9t11 may be an effective adjunct to COX-2 inhibition for treating chronic inflammation.
TL;DR: LA increased DHA production in the phospholipid fraction of hepatocytes isolated from fish fed 0 and 0.5% EPA and/or DHA, indicating that LA has the potential to further increase the production of this health-beneficial FA in fish fed diets with low levels of EPA and or DHA.
Abstract: The aim of the present study was to investigate how EPA, DHA, and lipoic acid (LA) influence the different metabolic steps in the n-3 fatty acid (FA) biosynthetic pathway in hepatocytes from Atlantic salmon fed four dietary levels (0, 0.5, 1.0 and 2.0%) of EPA, DHA or a 1:1 mixture of these FA. The hepatocytes were incubated with [1-14C] 18:3n-3 in the presence or absence of LA (0.2 mM). Increased endogenous levels of EPA and/or DHA and LA exposure both led to similar responses in cells with reduced desaturation and elongation of [1-14C] 18:3n-3 to 18:4n-3, 20:4n-3, and EPA, in agreement with reduced expression of the Δ6 desaturase gene involved in the first step of conversion. DHA production, on the other hand, was maintained even in groups with high endogenous levels of DHA, possibly due to a more complex regulation of this last step in the n-3 metabolic pathway. Inhibition of the Δ6 desaturase pathway led to increased direct elongation to 20:3n-3 by both DHA and LA. Possibly the route by 20:3n-3 and then Δ8 desaturation to 20:4n-3, bypassing the first Δ6 desaturase step, can partly explain the maintained or even increased levels of DHA production. LA increased DHA production in the phospholipid fraction of hepatocytes isolated from fish fed 0 and 0.5% EPA and/or DHA, indicating that LA has the potential to further increase the production of this health-beneficial FA in fish fed diets with low levels of EPA and/or DHA.
TL;DR: Cold adaptation of Rhodosporidium kratochvilovae YM25235 was influenced by inhibition of PUFA biosynthesis by RKD12 gene knockout by decreasing the PUFA content in cell membranes and reducing the growth rate and membrane fluidity of YM 25235 at low temperature.
Abstract: The intention of this study was to investigate the role of polyunsaturated fatty acids (PUFA) in the cold adaptation of Rhodosporidium kratochvilovae YM25235 by knockout of the Δ12/Δ15-fatty acid desaturase gene (RKD12) to inactivate Δ12/Δ15-fatty acid desaturase. Polymerase chain reaction (PCR) amplification was used to detect the genomic structure of RKD12 gene in YM25235. The RKD12 gene was knocked out by DNA homologous recombination to inhibit the biosynthesis of PUFA. Then, the contents of linoleic acid (LNA) and α-linolenic acid (ALA) after gene knockout were investigated using a gas chromatography-mass spectrometer, followed by determination of the growth rate and membrane fluidity of YM25235 at low temperature. After PCR amplification, a 1611 bp genomic fragment was amplified from YM25235. When the RKD12 gene was knocked out, the contents of LNA and ALA in YM25235 significantly decreased. The growth rate and membrane fluidity of YM25235 decreased significantly at low temperature. Inhibition of PUFA biosynthesis by RKD12 gene knockout influenced cold adaptation of YM25235 by decreasing the PUFA content in cell membranes and reducing the growth rate and membrane fluidity of YM25235 at low temperature.
TL;DR: An assessment of the substrate specificity of the seven desaturases and three elongases that were introduced into canola by expressing individual proteins in yeast is presented, and a novel in vitro method is developed to distinguish between enzymes that desaturate CoA- and phosphatidylcholine-linked fatty acid substrates is developed.
Abstract: Production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in plant seed oils has been pursued to improve availability of these omega-3 fatty acids that provide important human health benefits. Canola (Brassica napus), through the introduction of 10 enzymes, can convert oleic acid (OLA) into EPA and ultimately DHA through a pathway consisting of two elongation and five desaturation steps. Herein we present an assessment of the substrate specificity of the seven desaturases and three elongases that were introduced into canola by expressing individual proteins in yeast. In vivo feeding experiments were conducted with 14 potential fatty acid intermediates in an OLA to DHA pathway to determine the fatty acid substrate profiles for each enzyme. Membrane fractions were prepared from yeast expression strains and shown to contain active enzymes. The elongases, as expected, extended acyl-CoA substrates in the presence of malonyl-CoA. To distinguish between enzymes that desaturate CoA- and phosphatidylcholine-linked fatty acid substrates, we developed a novel in vitro method. We show that a delta-12 desaturase from Phytophthora sojae, an omega-3 desaturase from Phytophthora infestans and a delta-4 desaturase from Thraustochytrium sp., all prefer phosphatidylcholine-linked acyl substrates with comparatively low use of acyl-CoA substrates. To further validate our method, a delta-9 desaturase from Saccharomyces cerevisiae was confirmed to use acyl-CoA as substrate, but could not use phosphatidylcholine-linked substrates. The results and the assay methods presented herein will be useful in efforts to improve modeling of fatty acid metabolism and production of EPA and DHA in plants.
TL;DR: The aim of this study was to develop a method for neutral fecal sterols determination in subjects receiving a normal diet with or without a plant sterols-enriched beverage using gas chromatography–mass spectrometry (GC/MS).
Abstract: The aim of this study was to develop a method for neutral fecal sterols determination in subjects receiving a normal diet with or without a plant sterols-enriched beverage using gas chromatography–mass spectrometry (GC/MS). Sample preparation conditions (homogenization of lyophilized feces with water) were evaluated. Sterol determination required direct hot saponification, unsaponifiable extraction with hexane, and the formation of trimethylsilyl (TMS) ether derivatives. The method allows the quantification of cholesterol, plant sterols and their metabolites (coprostanol, coprostanone, cholestanol, cholestanone, methylcoprostanol, methylcoprostanone, ethylcoprostenol, stigmastenol, ethylcoprostanol and ethylcoprostanone). Good linearity was obtained (r > 0.96) and interference was only observed for coprostanone, where the standard addition method proved necessary for quantification. The limits of detection (LOD) ranged from 0.10 to 3.88 µg/g dry feces and the limits of quantitation (LOQ) from 0.34 to 12.94 µg/g dry feces. Intra- and inter-assay precision (RSD %) were 0.9–9.2 and 2.1–11.3, respectively. Accuracy, expressed as percentage recovery (80–119%) was obtained for all determined sterols.
TL;DR: It was showed that blood lipid and fatty acid levels vary between healthy young men and women, but that the observed sex differences are not associated with common variants in candidate lipid metabolism genes.
Abstract: Blood lipids are associated with cardiovascular disease (CVD) risk. Moreover, circulating lipid and fatty acid levels vary between men and women, and evidence demonstrates these traits may be influenced by single nucleotide polymorphisms (SNP). Sex-genotype interactions related to blood lipids and fatty acids have been poorly investigated and may help elucidate sex differences in CVD risk. The goal of this study was to investigate if the influence of SNPs previously associated with blood lipids and fatty acids varies in a sex-specific manner. Lipids and fatty acids were measured in serum and red blood cells (RBC), respectively, in 94 adults (18–30 years) from the GONE FISHIN’ cohort and 118 age-matched individuals from the GOLDN cohort. HDL-c levels were higher and the total cholesterol/HDL-c (TC/HDL-c) ratio was lower in women versus men (p < 0.01). RBC palmitoleic acid and the stearoyl-CoA desaturase index were both higher in women (p < 0.01). Fatty acid desaturase (FADS) pathway activity (estimated using the ratio of eicosapentaenoic acid/alpha-linolenic acid) was higher in men (p < 0.01). The AA genotype for rs1800775 in CETP had a lower TC/HDL-c ratio in men, but not women (p
int = 0.03). Independent of sex, major alleles for rs174537 in FADS1 (GG) and rs3211956 in CD36 (TT) had higher arachidonic acid, lower dihomo-γ-linoleic acid, and a higher FADS1 activity compared to minor alleles. The current study showed that blood lipid and fatty acid levels vary between healthy young men and women, but that the observed sex differences are not associated with common variants in candidate lipid metabolism genes.
TL;DR: A recently developed FT-NIR spectroscopic methodology in conjunction with partial least squares analysis was applied to commercial products labeled EVOO purchased in College Park, MD, USA to rapidly predict whether they are authentic, potentially mixed with refined olive oil (RO) or other vegetable oil(s), or are of lower quality.
Abstract: Economically motivated adulteration (EMA) of extra virgin olive oils (EVOO) has been a worldwide problem and a concern for government regulators for a long time. The US Food and Drug Administration (FDA) is mandated to protect the US public against intentional adulteration of foods and has jurisdiction over deceptive label declarations. To detect EMA of olive oil and address food safety vulnerabilities, we used a previously developed rapid screening methodology to authenticate EVOO. For the first time, a recently developed FT-NIR spectroscopic methodology in conjunction with partial least squares analysis was applied to commercial products labeled EVOO purchased in College Park, MD, USA to rapidly predict whether they are authentic, potentially mixed with refined olive oil (RO) or other vegetable oil(s), or are of lower quality. Of the 88 commercial products labeled EVOO that were assessed according to published specified ranges, 33 (37.5%) satisfied the three published FT-NIR requirements identified for authentic EVOO products which included the purity test. This test was based on limits established for the contents of three potential adulterants, oils high in linoleic acid (OH-LNA), oils high in oleic acid (OH-OLA), palm olein (PO), and/or RO. The remaining 55 samples (62.5%) did not meet one or more of the criteria established for authentic EVOO. The breakdown of the 55 products was EVOO potentially mixed with OH-LNA (25.5%), OH-OLA (10.9%), PO (5.4%), RO (25.5%), or a combination of any of these four (32.7%). If assessments had been based strictly on whether the fatty acid composition was within the established ranges set by the International Olive Council (IOC), less than 10% would have been identified as non-EVOO. These findings are significant not only because they were consistent with previously published data based on the results of two sensory panels that were accredited by IOC but more importantly each measurement/analysis was accomplished in less than 5 min.
TL;DR: In summary, MCE-DAG reduced body fat mass likely by stimulating lipolysis in WAT and thermogenesis in BAT and reducing body weight and fat mass of MCE -DAG20 group mice.
Abstract: Medium chain fatty acid (MCFA) escapes the formation of chylomicrons in the small intestine, resulting in energy expenditure through beta-oxidation. Diacylglycerol (DAG) is susceptible to oxidation rather than being stored in the adipose tissue. This study was conducted to verify the effect of MCE-DAG oil on body fat mass in vivo. Male C57BL/6 mice were randomly assigned to four groups (n = 12) as follows: (1) normal diet (18% kcal from fat), (2) canola oil as a control (40% kcal from canola oil), (3) MCE-DAG10 (10% kcal from MCE-DAG + 30% kcal from canola oil), and (4) MCE-DAG20 (20% kcal from MCE-DAG + 20% kcal from canola oil). The body weight and fat mass of MCE-DAG20 group mice were decreased relative to those of control mice (P < 0.05 and P < 0.001, respectively). Serum triacylglycerol (TAG) was decreased in both MCE-DAG10 and MCE-DAG20 groups (P < 0.01 and P < 0.05, respectively). Hormone sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) were increased in the MCE-DAG20 group relative to the control in white adipose tissue (WAT) (P < 0.05). Uncoupling protein 1 (UCP1) was also increased in the MCE-DAG20 group relative to the control in brown adipose tissue (BAT) (P < 0.05). In summary, MCE-DAG reduced body fat mass likely by stimulating lipolysis in WAT and thermogenesis in BAT.
TL;DR: Principal components analysis of the relative abundances of all PL class species distinguished between neuroborreliosis patients and healthy subjects is compared, the first report comparing PL classes and their molecular species in neurobor Reliosis patientsand healthy subjects.
Abstract: In recent years, the number of patients suffering from Lyme Disease (LD) has significantly increased. The most dangerous manifestation of LD is neuroborreliosis associated with invasion of the central nervous system by Borrelia burgdorferi. Phospholipids (PL) and their metabolites are involved in inflammation, which plays a dominant, but still unclear, role in the pathogenesis of neuroborreliosis. We analyzed the plasma PL profiles of neuroborreliosis patients (n = 8) and healthy volunteers (n = 8) using a lipidomic approach. Significant increases in the lysophosphatidylcholines LysoPtdCho 16:0 and LysoPtdCho 18:2 were observed. The plasma of neuroborreliosis patients appeared to have an increased relative abundance of sphingomyelin CerPCho d18:1/24:1 and a decrease in CerPCho d18:0/18:0. Principal components analysis of the relative abundances of all PL class species distinguished between neuroborreliosis patients and healthy subjects. This is the first report comparing PL classes and their molecular species in neuroborreliosis patients and healthy subjects.
TL;DR: This is the first study to demonstrate that increases in dietary ALA but not DHA increase serum TPAn-3 and THA in rats, suggesting that both fatty acids are precursors to DHA in the biosynthetic pathway.
Abstract: n-3 Tetracosapentaenoic acid (24:5n-3, TPAn-3) and tetracosahexaenoic acid (24:6n-3, THA) are believed to be important intermediates to docosahexaenoic acid (DHA, 22:6n-3) synthesis. The purpose of this study is to report for the first time serum concentrations of TPAn-3 and THA and their response to changing dietary α-linolenic acid (18:3n-3, ALA) and DHA. The responses will then be used in an attempt to predict the location of these fatty acids in relation to DHA in the biosynthetic pathway. Male Long Evans rats (n = 6 per group) were fed either a low (0.1% of total fatty acids), medium (3%) or high (10%) ALA diet with no added DHA, or a low (0%), medium (0.2%) or high (2%) DHA diet with a background of 2% ALA for 8 weeks post-weaning. Serum n-3 and n-6 polyunsaturated fatty acid (PUFA) concentrations (nmol/mL ± SEM) were determined by gas chromatography–mass spectrometry. Serum THA increases from low (0.3 ± 0.1) to medium (5.8 ± 0.7) but not from medium to high (4.6 ± 0.9) dietary ALA, while serum TPAn-3 increases with increasing dietary ALA from 0.09 ± 0.04 to 0.70 ± 0.09 to 1.23 ± 0.14 nmol/mL. Following DHA feeding, neither TPAn-3 or THA change across all dietary DHA intake levels. Serum TPAn-3 demonstrates a similar response to dietary DHA. In conclusion, this is the first study to demonstrate that increases in dietary ALA but not DHA increase serum TPAn-3 and THA in rats, suggesting that both fatty acids are precursors to DHA in the biosynthetic pathway.