Effects of omega-3 fatty acids on intravascular lipolysis of very-low-density lipoproteins in humans

Metabolism ◽  
1995 ◽  
Vol 44 (9) ◽  
pp. 1223-1230 ◽  
Author(s):  
Sidika E. Kasim-Karakas ◽  
Revital Herrmann ◽  
Rogelio Almario
2004 ◽  
Vol 10 (24) ◽  
pp. 8275-8283 ◽  
Author(s):  
Iris J. Edwards ◽  
Isabelle M. Berquin ◽  
Haiguo Sun ◽  
Joseph T. O’Flaherty ◽  
Larry W. Daniel ◽  
...  

2021 ◽  
Vol 8 (7) ◽  
pp. 121
Author(s):  
Dongmei Xing ◽  
Baogen Wang ◽  
Hong Lu ◽  
Tao Peng ◽  
Jianming Su ◽  
...  

Fatty liver is closely associated with elevated concentrations of nonesterified fatty acids (NEFA) and a low level of very low-density lipoproteins (VLDL) in blood of dairy cows. High NEFA inhibit the VLDL synthesis and assembly, and cause hepatic triacylglycerol (TAG) deposition. Sirtuin 3 (SIRT3), a mitochondrial deacetylase, antagonizes NEFA-induced TAG accumulation through modulating expressions of fatty acid synthesis and oxidation genes in cow hepatocytes. However, the role of SIRT3 in the VLDL synthesis and assembly was largely unknown. Here we aimed to test whether SIRT3 would recover the synthesis and assembly of VLDL in cow hepatocytes induced by high NEFA. Primary cow hepatocytes were isolated from 3 Holstein cows. Hepatocytes were infected with SIRT3 overexpression adenovirus (Ad-SIRT3), SIRT3-short interfering (si) RNA, or first infected with Ad-SIRT3 and then incubated with 1.0 mM NEFA (Ad-SIRT3 + NEFA). Expressions of key genes in VLDL synthesis and the VLDL contents in cell culture supernatants were measured. SIRT3 overexpression significantly increased the mRNA abundance of microsomal triglyceride transfer protein (MTP), apolipoprotein B100 (ApoB100) and ApoE (p < 0.01), and raised VLDL contents in the supernatants (p < 0.01). However, SIRT3 silencing displayed a reverse effect in comparison to SIRT3 overexpression. Compared with NEFA treatment alone, the Ad-SIRT3 + NEFA significantly upregulated the mRNA abundance of MTP, ApoB100 and ApoE (p < 0.01), and increased VLDL contents in the supernatants (p < 0.01). Our data demonstrated that SIRT3 restored the synthesis and assembly of VLDL in cow hepatocytes challenged with NEFA, providing an in vitro basis for further investigations testing its feasibility against hepatic TAG accumulation in dairy cows during the perinatal period.


Author(s):  
C. Srinivasa ◽  
K. La Kshminarayan ◽  
V. Srinivas ◽  
B. V. S. Chandrasekhar

Background: Current treatment with statins has become an integral part of vascular diseases but monotherapy has a significant residual event rate. Due to particularly one of the factor associated with atherogenic lipid phenotype that is characterized by a low high-density lipoprotein (HDL) cholesterol and increase in non-HDL cholesterol like Low-Density Lipoprotein (LDL). Omega-3 Fatty acids have demonstrated a preventiverole in primary and, particularly secondary cardiovascular diseases.  Hence this study was planned to compare the efficacy of Atorvastatin alone with Atorvastatin and Omega-3 fatty acids in treatment in hyperlipidaemia patients. Methods: The study was comparative, randomized, and prospective and open labeled conducted in MI patients. A total of 100 patients were selected based on inclusion and exclusion criteria. They were divided randomly into two Groups (Group–A and Group-B). Group-A was given Atorvastatin 10mg/day and Group-B was given Atorvastatin 10mg/day and Omega-3 fatty acids 600mg/day for 6 months. Follow up was done every month and efficacy was measured by assessing the lipoprotein levels in serum. Results: The results were compared before treatment and after 6 months treatment.The levels were significantly decreased Total Cholesterol (TC), LDL, Low-Density Lipoprotein (VLDL), Triglycerides (TG) and HDL levels were increased in Group–A and Group-B. When these results compared between two Groups the HDL levels were increased also it shown high significance (<0.001) but there were no significance changes in other cholesterol levels. Conclusion: The present study results showed that Atorvastatin and Omega-3 fatty acids treatment was more effective than Atorvastatin alone treatment in improving HDL-C levels from base line and it may have a additive effect in major coronary artery diseases.


2002 ◽  
Vol 283 (2) ◽  
pp. L310-L318 ◽  
Author(s):  
Alan J. Ryan ◽  
Jheem D. Medh ◽  
Diann M. McCoy ◽  
Ronald G. Salome ◽  
Rama K. Mallampalli

We examined whether administration of very low-density lipoproteins (VLDL) to pregnant rats increases surfactant phosphatidylcholine (PtdCho) content in fetal pre-type II alveolar epithelial cells. VLDL-triglycerides are hydrolyzed to fatty acids by lipoprotein lipase (LPL), an enzyme activated by heparin. Fatty acids released by LPL can incorporate into the PtdCho molecule or activate the key biosynthetic enzyme cytidylyltransferase (CCT). Dams were given BSA, heparin, VLDL, or VLDL with heparin intravenously. Radiolabeled VLDL given to the pregnant rat crossed the placenta and was distributed systemically in the fetus and incorporated into disaturated PtdCho (DSPtdCho) in pre-type II cells. Maternal administration of VLDL with heparin increased DSPtdCho content in cells by 45% compared with control ( P < 0.05). VLDL produced a dose-dependent, saturable, and selective increase in CCT activity. VLDL did not significantly alter immunoreactive CCT content but increased palmitic, stearic, and oleic acids in pre-type II cells. Furthermore, hypertriglyceridemic apolipoprotein E knockout mice contained significantly greater levels of DSPtdCho content in alveolar lavage and CCT activity compared with either LDL receptor knockout mice or wild-type controls that have normal serum triglycerides. Thus the nutritional or genetic modulation of serum VLDL-triglycerides provides specific fatty acids that stimulate PtdCho synthesis and CCT activity thereby increasing surfactant content.


1978 ◽  
Vol 176 (1) ◽  
pp. 169-174 ◽  
Author(s):  
P Thomopoulos ◽  
M Berthelier ◽  
D Lagrange ◽  
M J Chapman ◽  
M H Laudat

The effect of human plasma lipoproteins on lipogenesis from glucose has been studied in isolated rat adipocytes. The very-low-density lipoproteins increased lipogenesis specifically, whereas low-density lipoproteins and high-density lipoproteins were without effect. Such stimulation could be reproduced with partially delipidated very-low-density lipoproteins. Nod-esterified fatty acids and glycerol were also without effect. Pretreatment of the adipocytes with trypsin did not alter the effect of very-low-density lipoprotein. The presence of Ca2+ was required for the full activation of lipogenesis. The synthesis of acylglycerol fatty acids and of acylglycerol glycerol were equally increased. The effect of very-low-density lipoprotein was not additive to that of insulin. It is suggested that very-low-density lipoprotein may directly stimulate lipogenesis in fat-cells, particularly in states when the lipoproteins are present at high concentration in the circulation.


Author(s):  
Fotios Barkas ◽  
Tzortzis Nomikos ◽  
Evangelos Liberopoulos ◽  
Demosthenes Panagiotakos

Background: Although a cholesterol-lowering diet and the addition of plant sterols and stanols are suggested for the lipid management of children and adults with familial hypercholesterolemia, there is limited evidence evaluating such interventions in this population. Objectives: To investigate the impact of cholesterol-lowering diet and other dietary interventions on the incidence or mortality of cardiovascular disease and lipid profile of patients with familial hypercholesterolemia. Search methods: Relevant trials were identified by searching US National Library of Medicine National Institutes of Health Metabolism Trials Register and clinicaltrials.gov.gr using the following terms: diet, dietary, plant sterols, stanols, omega-3 fatty acids, fiber and familial hypercholesterolemia. Selection criteria: Randomized controlled trials evaluating the effect of cholesterol-lowering diet or other dietary interventions in children and adults with familial hypercholesterolemia were included. Data collection and analysis: Two authors independently assessed the trial eligibility and bias risk and one extracted the data, with independent verification of data extraction by a colleague. Results: A total of 17 trials were finally included, with a total of 376 participants across 8 comparison groups. The included trials had either a low or unclear bias risk for most of the parameters used for risk assessment. Cardiovascular incidence or mortality were not evaluated in any of the included trials. Among the planned comparisons regarding patients&rsquo; lipidemic profile, a significant difference was noticed for the following comparisons and outcomes: omega-3 fatty acids reduced triglycerides (mean difference [MD]: -0.27 mmol/L, 95% confidence interval [CI]: -0.47 to -0.07, p&lt;0.01) when compared with placebo. A non-significant trend towards a reduction in subjects&rsquo; total cholesterol (MD: -0.34, 95% CI: -0.68 to 0, mmol/L, p=0.05) and low-density lipoprotein cholesterol (MD: -0.31, 95% CI: -0.61 to 0, mmol/L, p=0.05) was noticed. In comparison with cholesterol-lowering diet, the additional consumption of plant stanols decreased total cholesterol (MD: -0.62 mmol/l, 95% CI: -1.13 to -0.11, p=0.02) and low-density lipoprotein cholesterol (MD: -0.58 mmol/l, 95% CI: -1.08 to -0.09, p=0.02). The same was by plant sterols (MD: -0.46 mmol/l, 95% CI: -0.76 to -0.17, p&lt;0.01 for cholesterol, and MD: -0.45 mmol/l, 95% CI: -0.74 to -0.16, p&lt;0.01 for low-density lipoprotein cholesterol). No heterogeneity was noticed among the studies included in these analyses. Conclusions: Available trials confirm that the addition of plant sterols or stanols has a cholesterol-lowering effect on such individuals. On the other hand, supplementation with omega-3 fatty acids effectively reduces triglycerides and might have a role in lowering the cholesterol of patients with familial hypercholesterolemia. Additional studies are needed to investigate the effectiveness of a cholesterol-lowering diet or the addition of soya protein and dietary fibers to a cholesterol-lowering diet in familial hypercholesterolemia.


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