scholarly journals “Insulin-Like” Effects of Palmitate Might Contribute to the Development of Insulin Resistance in Hypothalamic Neurons

Author(s):  
Martin Benzler ◽  
Jonas Benzler ◽  
Sigrid Stoehr ◽  
Cindy Hempp ◽  
Mohammed Z. Rizwan ◽  
...  

Saturated fatty acids are implicated in the development of metabolic diseases, including obesity and type 2 diabetes. There is evidence, however, that polyunsaturated fatty acids can counteract the pathogenic effects of saturated fatty acids. To gain insight into the early molecular mechanisms by which fatty acids influence hypothalamic inflammation and insulin resistance, we performed time-course experiments in a hypothalamic cell line, using different durations of treatment with the saturated fatty acid palmitate, and the omega-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA). Western blot analysis revealed that palmitate elevated the protein levels of phospho(p)AKT in a time-dependent manner. This effect seems involved in the pathogenicity of palmitate, as temporary inhibition of the PI3K/AKT pathway by selective PI3K inhibitors prevented palmitate-induced insulin resistance. Similarly to palmitate, DHA also increased levels of pAKT, but to a weaker extent. Co-administration of DHA with palmitate decreased pAKT close to the basal level after 8 h, and prevented palmitate-induced insulin resistance after 12 h. Measurement of the inflammatory markers pJNK and pNFκB-p65 revealed tonic elevation of both markers in the presence of palmitate alone. DHA alone transiently induced elevation of pJNK, returning to basal levels by 12 h treatment. Co-administration of DHA with palmitate prevented palmitate-induced inflammation after 12 h, but not at earlier time points.

2014 ◽  
Vol 4 (1) ◽  
pp. 31-39
Author(s):  
Siwitri Kadarsih

The objective was to get beef that contain unsaturated fatty acids (especially omega 3 and 6), so as to improve intelligence, physical health for those who consume. The study design using CRD with 3 treatments, each treatment used 4 Bali cattle aged approximately 1.5 years. Observations were made 8 weeks. Pasta mixed with ginger provided konsentrat. P1 (control); P2 (6% saponification lemuru fish oil, olive oil 1%; rice bran: 37.30%; corn: 62.70%; KLK: 7%, ginger paste: 100 g); P3 (lemuru fish oil saponification 8%, 2% olive oil; rice bran; 37.30; corn: 62.70%; KLK: 7%, ginger paste: 200 g). Konsentrat given in the morning as much as 1% of the weight of the cattle based on dry matter, while the grass given a minimum of 10% of the weight of livestock observation variables include: fatty acid composition of meat. Data the analyzies qualitative. The results of the study showed that the composition of saturated fatty acids in meat decreased and an increase in unsaturated fatty acids, namely linoleic acid (omega 6) and linolenic acid (omega 3), and deikosapenta deikosaheksa acid.Keywords : 


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ban-Hock Khor ◽  
◽  
Sharmela Sahathevan ◽  
Ayesha Sualeheen ◽  
Mohammad Syafiq Md Ali ◽  
...  

AbstractThe metabolic impact of circulating fatty acids (FAs) in patients requiring hemodialysis (HD) is unknown. We investigated the associations between plasma triglyceride (TG) FAs and markers of inflammation, insulin resistance, nutritional status and body composition. Plasma TG-FAs were measured using gas chromatography in 341 patients on HD (age = 55.2 ± 14.0 years and 54.3% males). Cross-sectional associations of TG-FAs with 13 markers were examined using multivariate linear regression adjusted for potential confounders. Higher levels of TG saturated fatty acids were associated with greater body mass index (BMI, r = 0.230), waist circumference (r = 0.203), triceps skinfold (r = 0.197), fat tissue index (r = 0.150), serum insulin (r = 0.280), and homeostatic model assessment of insulin resistance (r = 0.276), but lower malnutrition inflammation score (MIS, r =  − 0.160). Greater TG monounsaturated fatty acid levels were associated with lower lean tissue index (r =  − 0.197) and serum albumin (r =  − 0.188), but higher MIS (r = 0.176). Higher levels of TG n-3 polyunsaturated fatty acids (PUFAs) were associated with lower MIS (r =  − 0.168) and interleukin-6 concentrations (r =  − 0.115). Higher levels of TG n-6 PUFAs were associated with lower BMI (r =  − 0.149) but greater serum albumin (r = 0.112). In conclusion, TG monounsaturated fatty acids were associated with poor nutritional status, while TG n-3 PUFAs were associated with good nutritional status. On the other hand, TG saturated fatty acids and TG n-6 PUFAs had both favorable and unfavorable associations with nutritional parameters.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Frida Dangardt ◽  
Yun Chen ◽  
Eva Gronowitz ◽  
Jovanna Dahlgren ◽  
Peter Friberg ◽  
...  

Obese adolescents have high concentrations of saturated fatty acids and low omega-3 long-chain polyunsaturated fatty acids (LCUFAs) in plasma phospholipids. We aimed to investigate effects of omega-3 LCPUFA supplementation to obese adolescents on skeletal muscle lipids and glucose and insulin homeostasis. Twenty-five obese adolescents (14–17 years old, 14 females) completed a randomized double-blind crossover study supplying capsules containing either 1.2 g omega-3 LCPUFAs or placebo, for 3 months each with a six-week washout period. Fasting blood glucose, insulin, leptin, adiponectin, and lipids were measured. Intravenous glucose tolerance test (IVGTT) and euglycemic-hyperinsulinemic clamp were performed, and skeletal muscle biopsies were obtained at the end of each period. The concentrations of EPA, DHA, and total omega-3 PUFA in muscle phospholipids increased in both sexes. In the females, omega-3 LCPUFA supplementation improved glucose tolerance by 39% (P=0.04) and restored insulin concentration by 34% (P=0.02) during IVGTT. Insulin sensitivity improved 17% (P=0.07). In males, none of these parameters was influenced by omega-3 supplementation. Thus, three months of supplementation of omega-3 LCPUFA improved glucose and insulin homeostasis in obese girls without influencing body weight.


Author(s):  
M. V. Kruchinina ◽  
M. V. Parulikova ◽  
S. A. Kurilovich ◽  
A. A. Gromov ◽  
M. V. Shashkov ◽  
...  

The aim of this work is to study the possibility of using blood serum (BS) fatty acids (FA) and erythrocytes (ER) as diagnostic markers of the severity of NAFLD. Materials and methods. We examined 52 patients with NAFLD (51.8 ± 3.9 years), confirmed by the NLFS index, and 20 apparently healthy men (49.2 ± 4.5 years). The degree of liver fibrosis was established by indirect elastometry (FibroScan® 502 Echosens, France). 27 patients had an initial degree of fibrosis (F0-1), 25 had severe fibrosis (F2-4). The study of the composition of fatty acids of Er and BS was carried out using a GC / MS system based on three Agilent 7000B quadrupoles (USA). Results. Significant differences in the levels of fatty acids in blood serum and erythrocyte membranes in patients with NAFLD were revealed, associated with the degree of fibrosis and necroinflammatory activity. To distinguish between mild and severe fibrosis in NAFLD, the levels of saturated fatty acids (myristic, pentadecane, margarine) and omega-3 PUFAs (eicosapentaenoic, docosapentaenoic, docosahexaenoic) were found to be significant (p = 0.002-0.0003). Saturated and monounsaturated FAs (palmitelaidic, palmitoleic, vaccenic) played a key role in differentiating the degree of necroinflammatory activity (minimal versus pronounced) (p = 0.03-0.005). The created diagnostic panels (FA of blood serum and erythrocyte membranes) made it possible to differentiate patients with NAFLD with varying degrees of fibrosis. Correlations of FA levels in erythrocyte membranes and blood serum with manifestations of metabolic syndrome, indicators of liver damage in patients with NAFLD were revealed. Conclusions. The established differences in fatty acid profiles of blood serum and erythrocyte membranes in patients with NAFLD, associated with the degree of fibrosis, necroinflammatory activity, manifestations of metabolic syndrome and indicators of liver damage, should be considered as promising biomarkers for assessing the severity of NAFLD.


2010 ◽  
Vol 298 (6) ◽  
pp. E1122-E1130 ◽  
Author(s):  
Sun Ju Choi ◽  
Francis Kim ◽  
Michael W. Schwartz ◽  
Brent E. Wisse

Hypothalamic inflammation induced by high-fat feeding causes insulin and leptin resistance and contributes to the pathogenesis of obesity. Since in vitro exposure to saturated fatty acids causes inflammation and insulin resistance in many cultured cell types, we determined how cultured hypothalamic neurons respond to this stimulus. Two murine hypothalamic neuronal cell cultures, N43/5 and GT1–7, were exposed to escalating concentrations of saturated fatty acids for up to 24 h. Harvested cells were evaluated for activation of inflammation by gene expression and protein content. Insulin-treated cells were evaluated for induction of markers of insulin receptor signaling (p-IRS, p-Akt). In both hypothalamic cell lines, inflammation was induced by prototypical inflammatory mediators LPS and TNFα, as judged by induction of IκBα (3- to 5-fold) and IL-6 (3- to 7-fold) mRNA and p-IκBα protein, and TNFα pretreatment reduced insulin-mediated p-Akt activation by 30% ( P < 0.05). By comparison, neither mixed saturated fatty acid (100, 250, or 500 μM for ≤6 h) nor palmitate exposure alone (200 μM for ≤24 h) caused inflammatory activation or insulin resistance in cultured hypothalamic neurons, whereas they did in control muscle and endothelial cell lines. Despite the lack of evidence of inflammatory signaling, saturated fatty acid exposure in cultured hypothalamic neurons causes endoplasmic reticulum stress, induces mitogen-activated protein kinase, and causes apoptotic cell death with prolonged exposure. We conclude that saturated fatty acid exposure does not induce inflammatory signaling or insulin resistance in cultured hypothalamic neurons. Therefore, hypothalamic neuronal inflammation in the setting of DIO may involve an indirect mechanism mediated by saturated fatty acids on nonneuronal cells.


1998 ◽  
Vol 1998 ◽  
pp. 35-35 ◽  
Author(s):  
R.J. Dewhurst ◽  
P.J. King

Ruminant products have been criticised for the possible adverse effects of their saturated fatty acids on human health. Conversely, the omega-3 polyunsaturated fatty acids, notably those in fish oils, have been identified as beneficial components of the human diet. Earlier studies have shown that a small, but useful, amount of forage α-linolenic acid (C18:3), an omega-3 fatty acid, appears in ruminant products (Wood and Enser, 1996). The objective of the current work was to evaluate the range of α-linolenic acid concentrations in laboratory grass silages in order to assess the opportunities to modify ensiling techniques to increase the natural delivery of omega-3 fatty acid from grass silage to milk or meat.


Crustaceana ◽  
2016 ◽  
Vol 89 (10) ◽  
pp. 1135-1147 ◽  
Author(s):  
Abdullah Öksüz ◽  
Yavuz Mazlum

This research was conducted to evaluate the nutrient content ofAstacus leptodactylusin various populations in the lakes Iznik and Egirdir, as well as in Hirfanlı Dam Lake and Keban Dam Lake, all in Turkey. Crayfish meat yield ranged from a minimum of 11.3% to a maximum of 16.3% of wet weight in specimens from Keban and Iznik, respectively. Meat yield was significantly different, depending on the living environment. The protein content of the meat ofA. leptodactylusranged from 15.4 to 17.5%. The moisture content of crayfish was significantly lower in the high lipid containing Iznik Lake’s crayfish. Crayfish lipids were poor in saturated fatty acids, but rich in PUFA’s and in particular EPA, DHA and ARA. In all groups, the major saturated fatty acids were palmitic acid, stearic acid and myristic acid. Among the omega-6 fatty acid series, a high level of ARA was observed in crayfish meat.EPA may be considered as the major omega-3 fatty acid in crayfish lipids. There was no single fatty acid indicating regional differences in crayfish specimens.


2013 ◽  
Vol 67 (3) ◽  
Author(s):  
Adriána Bednárová ◽  
Ján Mocák ◽  
Walter Gössler ◽  
Margit Velik ◽  
Josef Kaufmann ◽  
...  

AbstractThe main aim of the present study was to find differences in the content of fatty acids and variations in elemental composition in beef samples of longissimus dorsi muscle related to cattle age and gender. A further goal was to describe interrelations among the selected variables (descriptors) characterising the samples. For this purpose, an extensive data table was compiled, which contains chemical descriptors specifying forty-six beef samples originating from four well-known Austrian grassland-based beef labels. The following descriptors were investigated: (a) concentrations of 33 fatty acids, (b) concentrations of 19 elements, (c) contents of dry-mass, protein, intramuscular fat, and ash, (d) total content of saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA), and poly-unsaturated fatty acids (PUFA), (e) total contents of omega-3 (n-3) and omega-6 (n-6) PUFA and their ratio. The correlation analysis provided a number of statistically significant correlations among the descriptors, which were concordant with the results of the principal component analysis and cluster analysis. Furthermore, the effect of age and gender of cattle (both acting as target factors) on the fatty acid content and elemental composition of beef was examined by analysis of variance (ANOVA) and appropriate non-parametric tests. Several important interrelations among the beef characteristics investigated were also discovered. Finally, the most relevant beef descriptors were utilised in linear discrimination analysis (LDA) for predicting the slaughter age of the cattle for beef authentication.


2005 ◽  
Vol 280 (43) ◽  
pp. 35896-35903 ◽  
Author(s):  
Yutong Wang ◽  
John F. Oram

Abnormal high density lipoprotein (HDL) metabolism among patients with diabetes and insulin resistance may contribute to their increased risk of atherosclerosis. ATP-binding cassette transporter ABCA1 mediates the transport of cholesterol and phospholipids from cells to HDL apolipoproteins and thus modulates HDL levels and atherogenesis. Unsaturated fatty acids, which are elevated in diabetes, impair the ABCA1 pathway in cultured cells by destabilizing ABCA1 protein. Here we examined the cellular pathway that mediates the ABCA1 destabilizing effects of fatty acids. The long-chain acyl-CoA synthetase inhibitor triacsin C completely reversed fatty acid-induced ABCA1 destabilization, indicating that fatty acids need to be activated to their CoA derivatives to enhance ABCA1 degradation. Unsaturated but not saturated fatty acids stimulated phospholipase D (PLD) activity, the PLD inhibitor 1-butanol prevented the unsaturated fatty acid-induced reduction in ABCA1 levels, and the PLD2 activator mastoparan markedly reduced ABCA1 protein levels, implicating a role for PLD2 in the ABCA1 destabilizing effects of fatty acids. Unsaturated fatty acids and mastoparan increased phosphorylation of ABCA1 serines. PLD2 small interfering RNA abolished the ability of unsaturated fatty acids to inhibit lipid transport activity, to reduce protein levels, and to increase serine phosphorylation of ABCA1. The diacylglycerol analog oleoylacetylglycerol also reduced ABCA1 protein levels and increased its serine phosphorylation, suggesting that PLD2-generated diacylglycerols promote the destabilizing phosphorylation of ABCA1. These data provide evidence that intracellular unsaturated acyl-CoA derivatives destabilize ABCA1 by activating a PLD2 signaling pathway.


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