Benefits of Fish Oil Consumption over Other Sources of Lipids on Metabolic Parameters in Obese Rats

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.

Fatty acids composition and in vivo biochemical effects of Aleurites moluccana seed (Candlenut) in obese wistar rats

BACKGROUND

Candlenut (CN) has been used indiscriminately for weight loss. In vivo effects of CN in different doses are scarce.

OBJECTIVE

To evaluate the effects of CN ingestion in obese rats.

DESIGN

Thirty animals (obese and non-obese) received one of three different types of treatments: placebo, CN ingestion in a popular therapeutic regimen (8 days with oral administration of 0.2 mg/kg followed by 20 days with doses of 0.4 mg/kg), and ingestion of a doubled popular dose-called 2CN. Treatment was maintained for 28 days.

RESULTS

The fatty acid profile of CN indicated mainly linolelaidic and palmitoleic acids. Rats receiving CN and 2CN showed reduced plasmatic levels of glucose and lipoproteins (p < 0.05). A dose-dependent carcass fat reduction was observed (p < 0.05). Blood levels of aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) reduced with CN and increased with 2CN doses (p < 0.05). Alanine aminotransferase (ALT) and the atherogenic index remained similar among all treatments (p > 0.05). Hepatic vacuolation decreased with CN, but the 2CN dose produced mononuclear leucocyte infiltrate.

CONCLUSIONS

Although CN presented beneficial effects on the metabolism of rats, it also caused increased risk of liver damage.

Effect of different types of oil intake on the blood index and the intestinal flora of rats

Dietary fat is an important part of human diet and has a close relationship with human health. However, it is still unclear how gut microbiota in adolescent responds to dietary fats at a normal dose. In this study, fat-free group (BC) was used as blank control group, we explored blood index and gut microbiota structure in growing rat(aged 1 months) after feeding a normal dose of 16.9% stewed lard(SL), refined lard(RL), fish oil(FO) and soybean oil(SO) for 6 weeks, respectively. The results showed that compared with RL group, SL group showed reduced fasting blood sugar and blood lipid levels and improved nutrient absorption capacity of the intestine. The blood indexes of glucose (Glu), total cholesterol (TC) and total triglyceride (TG) in FO treatment group were relatively low. The abundance of Bacteroidetes in the BC group decreased, and the abundance of Firmicutes increased. The Firmicutes/Bacteroidetes ratio of the FO group was relatively low, and the Firmicutes/Bacteroidetes ratio of the SL group and the SO group was lower than that of the RL group. The abundance of Bacteroidaceae in the SL group was increased. Research results showed that fat-free diets will increase the risk of obesity to a certain extent; compared with refined lard, stewed lard, soybean oil and fish oil can reduce the risk of obesity to a certain extent. The present study could find that the addition and types of dietary fat will affect the abundance and diversity of rat intestinal flora, and provide some information for nutritional evaluation about these dietary lipids.

Abdominal Obesity: An Independent Influencing Factor of Visuospatial and Executive/Language Ability and the Serum Levels of Aβ40/Aβ42/Tau Protein

Background

Although obesity affects human health and cognitive function, the influence of abdominal obesity on cognitive function is still unclear.

Methods

The MoCA scale was used to evaluate the overall cognitive function and the function of each subitem of 196 subjects, as well as the SDMT and TMT-A scales for evaluating the attention and information processing speed. In addition, radioimmunoassay was used to detect the serum levels of Aβ40, Aβ42, and tau protein in 45 subjects. Subjects were divided into abdominal and nonabdominal obesity groups. Before and after correcting confounding factors, the differences in cognitive scale evaluation indexes and three protein levels between the two groups were compared. We also explore further the correlation between various cognitive abilities and the waist circumference/levels of the three proteins. Linear regression was used to identify the independent influencing factors of various cognitive functions and three protein levels.

Results

After correcting for multiple factors, we observed the lower scores of visuospatial function, execution, and language in the MoCA scale, as well as higher levels of Aβ40 and tau protein in the abdominal obesity group, supported by the results of correlation analysis. Abdominal obesity was identified as an independent negative influencing factor of MoCA visual space, executive power, and language scores and an independent positive influencing factor of Aβ40, Aβ42, and tau protein levels.

Conclusion

Abdominal obesity may play a negative role in visuospatial, executive ability, and language function and a positive role in the Aβ40, Aβ42, and tau protein serum levels.

Selective Consumption of Fish Oil at End of the Day Increases the Physiological Fatty Acid Compositions of Eicosapentaenoic Acid and Docosahexaenoic Acid in Mice

Diets with high daily fat consumption are associated with excess weight. However, the effects of fat type and consumption timing on excess weight remain unclear. We investigated the selection of a 30% (w/w) fat diet of soybean oil (SOY), lard (LARD), and fish oil (FISH) on the metabolic parameters of mice. Male C57BL/6 mice were divided into the double SOY-box (w-SOY), SOY-box/LARD-box (SOY-vs-LARD), or SOY-box/FISH-box (SOY-vs-FISH) groups and allowed to selectively consume for 8 weeks. The total energy intake was similar for all groups, but the mice selectively chose to consume LARD over SOY and SOY over FISH. Body weight in the SOY-vs-LARD group was significantly higher than that in the w-SOY and SOY-vs-FISH groups. Additionally, minimal but selective consumption of an omega-3 fatty-acid-rich FISH diet at the end of the active period increased the physiological fatty acid compositions of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the SOY-vs-FISH group; their metabolic parameters were also lower than the SOY-vs-LARD group. In conclusion, selectively consuming small amounts of fish oil at the end of the day may prevent excess weight compared with LARD consumption.

Differential Effect of Four-Week Feeding of Different Dietary Fats on the Accumulation of Fat and the Cholesterol and Triglyceride Contents in the Different Fat Depots

The aim of the present study was to determine the effects of feeding of a high-fat diet containing different types of lipids for four weeks on the cholesterol and triglyceride contents of different fat depots and on body temperature in rats. Four groups of adult rats were fed 10% fat, containing either beef tallow, safflower oil, or fish oil, respectively, as well as a normal rodent diet with 4% fat, for four weeks. The rats on normal rodent diet consumed significantly more food and water than the rats in the other three groups. Rectal temperature increased only after four-week feeding with safflower oil fat. Increased fat deposition and adipocyte size were observed in rats fed safflower oil and beef tallow. In all fat pads of safflower oil-fed rats, cholesterol content was significantly higher than the other three groups. Feeding of beef tallow increased triglyceride depot without increasing cholesterol content. The rats fed fish oil had significantly less triglyceride and cholesterol deposition in adipose tissues than the rats fed safflower oil or beef tallow. These results clearly demonstrated the differences in fat deposition, adipocyte size and number, triglyceride and cholesterol accumulation in fat cells are dependent on the dietary lipid composition.

Fish oil and corn oil induced differential effect on beiging of visceral and subcutaneous white adipose tissue in high-fat-diet-induced obesity

Obesity is characterised by excessive accumulation of fat in white adipose tissue (WAT) which is compartmentalised into two anatomically and functionally diverse depots - visceral and subcutaneous. Advice to substitute essential polyunsaturated fatty acids (PUFAs) for saturated fatty acids is a cornerstone of various obesity management strategies. Despite an array of reports on the role of essential PUFAs on obesity, there still exists a lacuna on their mode of action in distinct depots i.e. visceral (VWAT) and subcutaneous (SWAT). The present study aimed to evaluate the effect of fish oil and corn oil on VWAT and SWAT in high-fat-diet-induced rodent model of obesity. Fish oil (FO) supplementation positively ameliorated the effects of HFD by regulating the anthropometrical and serum lipid parameters. FO led to an overall reduction in fat mass in both depots while specifically inducing beiging of adipocytes in SWAT as indicated by increased UCP1 and PGC1α. We also observed an upregulation of AMPKα and ACC1/2 phosphorylation on FO supplementation in SWAT suggesting a role of AMPK-PGC1α-UCP1 axis in beiging of adipose tissue. On the other hand, corn oil supplementation did not show any improvements in adipose tissue metabolism in both the depots of adipose tissue. The results were analysed using one-way ANOVA followed by Tukey's test in Graphpad Prism 5.0. Combined together our results suggest that n-3 PUFAs exert their anti-obesity effect by regulating adipokine secretion and inducing beiging of SWAT, hence increasing energy expenditure via thermogenic upregulation.

Fish oil diet effects on alveolar bone loss, in hypercholesterolemic rats

This study evaluated the effects of replacing a saturated fat diet by n-3 polyunsaturated fatty acids (n-3PUFA), on alveolar bone loss in hypercholesterolemic rats with experimental periodontitis (PD).

METHODS

Eight week old Wistar rats were assigned according to dietary intake. Control group (C, n = 15) fed a commercial diet throughout the experiment. Atherogenic group (AT, n = 30) fed AT diet for 3 weeks; thereafter, AT was randomized to receive either a n-3PUFA (n = 15) or to continue with AT (n = 15) diet. Subsequently, PD was induced in all groups by unilateral ligature (L) of the first molar (M1) of the left mandible, non-ligated contralateral molars served as controls. After every week of PD induction, 5 rats per group were euthanized. Serum was collected for lipids assays and hemi-mandibles were subjected to histomorphometric (% upper and lower interradicular bone volume and periodontal ligament height, hPDL) and radiographic analyses (periodontal bone support, PBS, in ligated teeth, between M1-M2).

RESULTS

Rats fed n-3PUFA diet rapidly induced a significant reduction in the serum lipids (p < 0.001). In all rats the ligated teeth showed a greater bone loss as compared with the unligated molars. At the end of the experiment the AT + L was the worst in % lower bone volume (p < 0.01), hPDL and PBS (p < 0.05). In contrast, rats fed n-3PUFA + L was similar to those rats fed C diet (p > 0.05).

CONCLUSION

Alveolar bone and dyslipidemia improved by substituting saturated fat intake for a n-3PUFA rich diet, in hypercholesterolemic rats with PD.

The Impact of OMEGA-3 Fatty Acids Supplementation on Insulin Resistance and Content of Adipocytokines and Biologically Active Lipids in Adipose Tissue of High-Fat Diet Fed Rats

It has been established that OMEGA-3 polyunsaturated fatty acids (PUFAs) may improve lipid and glucose homeostasis and prevent the "low-grade" state of inflammation in animals. Little is known about the effect of PUFAs on adipocytokines expression and biologically active lipids accumulation under the influence of high-fat diet-induced obesity. The aim of the study was to examine the effect of fish oil supplementation on adipocytokines expression and ceramide (Cer) and diacylglycerols (DAG) content in visceral and subcutaneous adipose tissue of high-fat fed animals. The experiments were carried out on Wistar rats divided into three groups: standard diet-control (SD), high-fat diet (HFD), and high-fat diet + fish oil (HFD+FO). The fasting plasma glucose and insulin concentrations were examined. Expression of carnitine palmitoyltransferase 1 (CPT1) protein was determined using the Western blot method. Plasma adipocytokines concentration was measured using ELISA kits and mRNA expression was determined by qRT-PCR reaction. Cer, DAG, and acyl-carnitine (A-CAR) content was analyzed by UHPLC/MS/MS. The fish oil supplementation significantly decreased plasma insulin concentration and Homeostatic Model Assesment for Insulin Resistance (HOMA-IR) index and reduced content of adipose tissue biologically active lipids in comparison with HFD-fed subjects. The expression of CPT1 protein in HFD+FO in both adipose tissues was elevated, whereas the content of A-CAR was lower in both HFD groups. There was an increase of adiponectin concentration and expression in HFD+FO as compared to HFD group. OMEGA-3 fatty acids supplementation improved insulin sensitivity and decreased content of Cer and DAG in both fat depots. Our results also demonstrate that PUFAs may prevent the development of insulin resistance in response to high-fat feeding and may regulate the expression and secretion of adipocytokines in this animal model.

Meat, Meat Products and Seafood as Sources of Energy and Nutrients in the Average Polish Diet

The aim of this study was to identify the share of meat, meat products and seafood in the contribution of energy and 22 nutrients to the average Polish diet. Data from the nationally representative sample of Polish population (2016 Household Budget Survey) on meat and seafood product consumption from 38,886 households (n = 99,230) were calculated into one person per month. The analyses were conducted for seven food groups (e.g., red meat, poultry) and 16 products (e.g., beef, chicken). Approximately 18.5% of energy is delivered from the sources such as meat, meat products and seafood, providing a higher percentage of 18 nutrients to the diet (e.g., 56.0% of vitamin B12, 52.3% of niacin, 44.9% of cholesterol, 41.5% of protein, 41.4%of vitamin D, 37.6% of monounsaturated fatty acids (MUFA), 37.4% of thiamin, 33.8% of zinc, 32.0% of total fats, 30.3% of saturated fatty acids (SFA), 29.6% of vitamin B6, 25.3% of riboflavin, 24.9% of phosphorus, 24.8% of iron, 22.5% of vitamin A, 21.6% of polyunsaturated fatty acids (PUFA) and 20.3% of sodium). For the contribution of 18 nutrients and energy, processed meat products were ranked first. These results should be taken into consideration in order to compose diets with adequate energy and nutrient contribution and also to analyze benefits and risk resulting from the current level of consumption of red and processed meat, fish and other seafood.