Hepatoprotective and Anti-Obesity Properties of Sardine By-Product Oil in Rats Fed a High-Fat Diet

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.

Anti-adiposity and lipid-lowering effects of schisandrol A in diet-induced obese mice

Lignan schisandrol A (SolA) is known to have antioxidant and anti-inflammatory effects. However, the impact of SolA on obesity is poorly understood. To test the hypothesis that SolA has anti-obesity effects, C57BL/6J mice were fed a high-fat diet with or without SolA (0.006%, w/w) for 16 weeks. SolA decreased visceral fat mass (10%) by increasing energy expenditure and upregulating white adipose tissue thermogenic genes mRNA expression. Furthermore, SolA upregulated adipose Lpl mRNA expression and decreased plasma free fatty acid (FFA), triglyceride (TG), apolipoprotein (apo) B, aspartate aminotransferase levels and TG/HDL-cholesterol and apoB/apoA1 ratios as well as hepatic lipid droplets. Increased hepatic β-oxidation and fecal FFA and TG levels were observed in the SolA-supplemented mice, suggesting an association of its lipid-lowering effect with increased hepatic β-oxidation, fecal fat excretion and adipose Lpl. Conclusionally, this study provides evidence on the protective effects of SolA against adiposity, dyslipidemia and nonalcoholic fatty liver disease in obese mice.

Blood Sugar, Haemoglobin and Malondialdehyde Levels in Diabetic White Rats Fed a Diet of Corn Flour Cookies

The purpose of the study was to analyse the chemical composition of corn cookies containing different types of sugar and fat, and determine their effect on physiological parameters in diabetic rats. The experimental animals were studied using a randomised block design with seven groups of rats. The test groups were as follows: group 1, negative control rats (normal) fed standard; group 2, positive control rats (diabetic) fed standard; group 3, diabetic rats fed wheat cookies; group 4, diabetic rats fed C1 corn cookies; group 5, diabetic rats fed C2 corn cookies; group 6, diabetic rats fed C3 corn cookies; and group 7, diabetic rats fed C4 corn cookies. The tests on the rats revealed that the cookies had significant effects on blood sugar, malondialdehyde (MDA) and haemoglobin levels as well as body weight parameters. Corn cookies containing crystalline coconut sugar and virgin coconut oil (VCO) were effective at lowering blood sugar and MDA levels while increasing haemoglobin and body weight in diabetic rats. Significantly, after four weeks on this diet, rats with diabetes mellitus were in the same overall condition as normal rats. These findings suggest that these cookies may be gluten-free functional foods suitable for diabetics. These findings suggest that diabetics can safely consume maize cookies.

Lowering n-6/n-3 Ratio as an Important Dietary Intervention to Prevent LPS-Inducible Dyslipidemia and Hepatic Abnormalities in ob/ob Mice

Obesity is closely associated with low-grade chronic and systemic inflammation and dyslipidemia, and the consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) may modulate obesity-related disorders, such as inflammation and dyslipidemia. An emerging research question is to understand the dietary intervention strategy that is more important regarding n-3 PUFA consumption: (1) a lower ratio of n-6/n-3 PUFAs or (2) a higher amount of n-3 PUFAs consumption. To understand the desirable dietary intervention method of n-3 PUFAs consumption, we replaced lard from the experimental diets with either perilla oil (PO) or corn oil (CO) to have identical n-3 amounts in the experimental diets. PO had a lower n-6/n-3 ratio, whereas CO contained higher amounts of PUFAs; it inherently contained relatively lower n-3 but higher n-6 PUFAs than PO. After the 12-week dietary intervention in ob/ob mice, dyslipidemia was observed in the normal chow and CO-fed ob/ob mice; however, PO feeding increased the high density lipoprotein-cholesterol (HDL-C) level; further, not only did the HDL-C level increase, the low density lipoprotein-cholesterol (LDL-C) and triglyceride (TG) levels also decreased significantly after lipopolysaccharide (LPS) injection. Consequently, extra TG accumulated in the liver and white adipose tissue (WAT) of normal chow- or CO-fed ob/ob mice after LPS injection; however, PO consumption decreased serum TG accumulation in the liver and WAT. PUFAs replacement attenuated systemic inflammation induced by LPS injection by increasing anti-inflammatory cytokines but inhibiting pro-inflammatory cytokine production in the serum and WAT. PO further decreased hepatic inflammation and fibrosis in comparison with the ND and CO. Hepatic functional biomarkers (aspartate aminotransferase (AST) and alanine transaminase (ALT) levels) were also remarkably decreased in the PO group. In LPS-challenged ob/ob mice, PO and CO decreased adipocyte size and adipokine secretion, with a reduction in phosphorylation of MAPKs compared to the ND group. In addition, LPS-inducible endoplasmic reticulum (ER) and oxidative stress decreased with consumption of PUFAs. Taken together, PUFAs from PO and CO play a role in regulating obesity-related disorders. Moreover, PO, which possesses a lower ratio of n-6/n-3 PUFAs, remarkably alleviated metabolic dysfunction in LPS-induced ob/ob mice. Therefore, an interventional trial considering the ratio of n-6/n-3 PUFAs may be desirable for modulating metabolic complications, such as inflammatory responses and ER stress in the circulation, liver, and/or WAT.