Influence of Omega-3 Fatty Acid-Rich Fish Oils on Hyperlipidemia: Effect of Eel, Sardine, Trout, and Cod Oils on Hyperlipidemic Mice

Different Sources of Omega-3 Fatty Acid Supplementation vs. Blood Lipid Profiles-A Study on a Rat Model

Dyslipidemia is a serious condition affecting an increasing number of people, and thus, preventive measures, including supplementation, are being developed. We aimed to compare the effect of linseed oil, its ethyl esters and fish oil supplementation on the serum lipid profiles of rats fed a high-fat diet. Wistar rats were divided into nine groups. Four of them were fed a high-fat diet for the whole experiment, four groups were fed a high-fat diet before the supplementation period and then the control one with supplements, and one was fed a control diet without supplements. The whole experiment lasted 12 weeks. A significant reduction in blood triglycerides, total cholesterol and the LDL fraction was noted in supplemented groups compared to the controls, especially in groups supplemented with ethyl esters of linseed oil and linseed oil compared to fish oil groups. The results were also more beneficial in groups where, in addition to supplementation, there was also a diet change from a high-fat diet to a control diet during the supplementation period. We may conclude that supplementation with omega-3 fatty acids, combined with a healthy diet, may be a good way of preventing or alleviating dyslipidemia.

Effects of Indonesian Shortfin Eel (Anguilla bicolor) By-Product Oil Supplementation on HOMA-IR and Lipid Profile in Obese Male Wistar Rats

The prevalence of people being overweight and obese has increased globally over the past decades. The use of omega-3 fatty acids-a compound usually primarily found in fish oil-has been known to improve the metabolic profile of obese patients. As the demand for eels increases, the number of waste products from the eels increases and creates environmental problems. This study was conducted to investigate the effect of a newly discovered Indonesian Shortfin eel by-product oil supplementation on the Homeostasis Model Assessment-Estimated Insulin Resistance (HOMA-IR) and lipid profiles of obese male (Lee index ≥ 0.3) Wistar rats (Rattus norvegicus). The oil was extracted from waste products (heads). Fifteen obese rats were divided into three groups and were administered NaCl (C), commercial fish oil (CO), and Indonesian shortfin eel by-product oil (EO). All groups had statistically significant differences in total cholesterol, LDL, and triglyceride levels (p < 0.05). The CO and EO group showed a significant decrease in total cholesterol, LDL, and triglyceride after treatment. However, no significant difference was found in HDL levels and HOMA-IR. The supplementation of Indonesian shortfin eel by-product oil significantly improved lipid profile while effectively mitigating environmental challenges.

Protective mechanisms of a microbial oil against hypercholesterolemia: evidence from a zebrafish model

A Western diet elevates the circulating lipoprotein and triglyceride levels which are the major risk factors in cardiovascular disease (CVD) development. Consumption of long-chain omega-3 fatty acids can stall the disease progression. Although these fatty acids can significantly impact the intestine under a hypercholesterolemic condition, the associated changes have not been studied in detail. Therefore, we investigated the alterations in the intestinal transcriptome along with the deviations in the plasma lipids and liver histomorphology of zebrafish offered DHA- and EPA-rich oil. Fish were allocated to 4 dietary treatments: a control group, a high cholesterol group and microbial oil groups with low (3.3%) and high (6.6%) inclusion levels. We quantified the total cholesterol, lipoprotein and triglyceride levels in the plasma. In addition, we assessed the liver histology, intestinal transcriptome and plasma lipidomic profiles of the study groups. The results suggested that higher levels of dietary microbial oil could control the CVD risk factor indices in zebrafish plasma. Furthermore, microbial oil-fed fish had fewer liver vacuoles and higher mRNA levels of genes involved in β-oxidation and HDL maturation. Analyses of the intestine transcriptome revealed that microbial oil supplementation could influence the expression of genes altered by a hypercholesterolemic diet. The plasma lipidomic profiles revealed that the higher level of microbial oil tested could elevate the long-chain poly-unsaturated fatty acid content of triglyceride species and lower the concentration of several lysophosphatidylcholine and diacylglycerol molecules. Our study provides insights into the effectiveness of microbial oil against dyslipidemia in zebrafish.

Effect of a new squalene synthase inhibitor on an ApoE-/- mouse model of atherosclerosis

Ηypercholesterolemia/hyperlipidemia in conjunction with oxidative stress and inflammatory processes contribute synergistically to the pathogenesis of atherosclerosis. We hereby evaluated the antiatherosclerotic effect of the multi-target derivative 4-methyl-2-(10H-phenothiazin-3-yl)morpholin-2-ol hydrobromide 1 in apoE^-/- mice; compound 1 is a potent antihyperlipidemic agent acting through Squalene Synthase inhibition, while it has exhibited an outstanding antioxidant and anti-inflammatory activity in various experimental animal models. The new analogue was evaluated in terms of its antiatherosclerotic/antioxidant effect in the ApoE^-/- transgenic mouse model. Its toxicity profile was also assessed by measuring the levels of four sensitive indicators of liver toxicity. Prolonged administration of 1 in ApoE^-/- mice fed with a western-type (wt) diet efficiently reduced the aortic atheromatic lesions, an effect that took place through a cholesterol lowering independent manner. In addition, 1 displayed a significant reduction not only of glucose but also of oxidative stress levels, while it did not cause any toxicity. To the best of our knowledge this is the first time that the antiatherosclerotic effect of a Squalene Synthase inhibitor is studied in this specific atherosclerosis mouse model. As a result, compound 1 may serve as a promising starting point towards developing new bioactive analogues against the onset and subsequent development of atherosclerosis.

Different ratios of DHA/EPA reverses insulin resistance by improving adipocyte dysfunction and lipid disorders in HFD-induced IR mice

Objective: Insulin resistance (IR) is linked to the development of diabetes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular disease (CVDs). Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from fish oils (FOs) were used to investigate their potential in high-fat diet (HFD)-induced IR mice under different ratios. Methods: A total of 84 male C57BL/6J (6 weeks old) mice were fed with HFD containing 45% kcal from fat for 16 weeks to establish the IR model. The IR mice were then fed with HFD or HFD + 4% DHA/EPA with different ratios (3 : 1, 1.5 : 1, 1 : 1, 1 : 1.5, 1 : 3, respectively) for another 12 weeks. During the experiment, the CON group (n = 12) was set to feed with a basic diet containing 10% kcal from fat. Results: HFD feeding for 16 weeks reduced insulin sensitivity and accelerated hypertrophy of white adipose tissue (WAT). Different ratios of DHA/EPA except for 1 : 1 decreased the HOMA-IR index, average area of adipocytes, and serum MDA, but increased the protein expression of PI3K. All ratios of DHA/EPA increased the protein expression of IRS-1, GLUT4, and adiponectin. Moreover, dietary DHA/EPA changed serum fatty acid (FA) composition by increasing the serum concentration of n-3 PUFAs. DHA/EPA supplements also improved serum lipid profiles (TG/TC/LDL-c/HDL-c, FFA) and reduced the hepatic steatosis area. Conclusions: The results indicate that an appropriate higher ratio of DHA (1.5 : 1) in DHA/EPA supplementation is recommended for IR prevention.

Effects of flaxseed on blood pressure, body mass index, and total cholesterol in hypertensive patients: A randomized clinical trial

OBJECTIVES

Given the antioxidant properties of flaxseed and its biologically active ingredients, this study was conducted to determine the effects of flaxseed supplementation on body mass index (BMI), blood pressure, and total cholesterol levels in patients with hypertension.

METHODS

In this triple-blind clinical trial, 112 patients, with an age range of 35 to 70 years, were randomized to 2 groups receiving 10 g (n = 45) and 30 g (n = 45) of flaxseed supplementation and 1 group receiving placebo (n = 45) for 12 weeks by stratified block randomization. They were evaluated in terms of systolic (SBP) and diastolic blood pressure (DBP), BMI, and total serum cholesterol. Physical activity was measured using the International Physical Activity Questionnaire-Short Form (IPAQ-SF) and food intake was assessed using the Food Frequency Questionnaire (FFQ). The data were analyzed with SPSS, version 22, using the chi-square, Kruskal-Wallis, repeated measures analysis, ANOVA, and ANCOVA tests.

RESULTS

The interaction effects among the study groups and time on the mean SBP (p = 0.001), DBP (p = 0.001), total cholesterol level (p = 0.032), and BMI (p < 0.001) were significant. During the study, the 30-g group achieved the best results, so that a 13.38-unit decrease in SBP was observed compared to a 1.72 unit increase in the placebo group and a 5.6-unit decrease in DBP was measured compared to a 2.39 unit increase in the placebo group. BMI decreased by 0.86 units compared to 0.06 units in the placebo group. Total cholesterol also decreased by 20.4 units compared to 11.86 units in the placebo group.

CONCLUSION

The results of this study showed that flaxseed can be effective in reducing blood pressure, total cholesterol, and body mass index in hypertensive patients in a twelve-week period.