Effect of Dietary Supplementation with Omega-3 Fatty Acid on the Generation of Regulatory T Lymphocytes and on Antioxidant Parameters and Markers of Oxidative Stress in the Liver Tissue of IL-10 Knockout Mice.

INTRODUCTION: chronic low-grade inflammation, or inflammaging, emerges as a crucial element in the aging process and is associated with cardiovascular and neurological diseases, sarcopenia, and malnutrition. Evidence suggests that omega-3 fatty acids present a potential therapeutic agent in the prevention and treatment of inflammatory diseases, mitigating oxidative stress, and improving muscle mass, attributes that are particularly relevant in the context of aging. The objective of the present study was to evaluate the effectiveness of supplementation with omega-3 fish oil in improving the immune response and oxidative stress in knockout mice for interleukin IL-10 (IL-10-/-). MATERIAL AND METHODS: female C57BL/6 wild-type (WT) and interleukin IL-10 knockout (IL-10-/-) mice were fed during 90 days with a standard diet (control groups), or they were fed/supplemented with 10% of the omega-3 polyunsaturated fatty acid diet (omega-3 groups). Muscle, liver, intestinal, and mesenteric lymph node tissue were collected for analysis. RESULTS: the IL-10-/-+O3 group showed greater weight gain compared to the WT+O3 (p = 0.001) group. The IL-10-/-+O3 group exhibited a higher frequency of regulatory T cells than the IL-10-/- group (p = 0.001). It was found that animals in the IL-10-/-+O3 group had lower levels of steatosis when compared to the IL-10-/- group (p = 0.017). There was even greater vitamin E activity in the WT group compared to the IL-10-/-+O3 group (p = 0.001) and WT+O3 compared to IL-10-/-+O3 (p = 0.002), and when analyzing the marker of oxidative stress, MDA, an increase in lipid peroxidation was found in the IL-10-/-+O3 group when compared to the IL-10-/- group (p = 0.03). Muscle tissue histology showed decreased muscle fibers in the IL-10-/-+O3, IL-10-/-, and WT+O3 groups. CONCLUSION: the findings show a decrease in inflammation, an increase in oxidative stress markers, and a decrease in antioxidant markers in the IL-10-/-+O3 group, suggesting that supplementation with omega-3 fish oil might be a potential intervention for inflammaging that characterizes the aging process and age-related diseases.

Effects of Different Vegetable Oils on the Nonalcoholic Fatty Liver Disease in C57/BL Mice.

Background: Nonalcoholic fatty liver disease (NAFLD) is the most common hepatic disorder, affecting 22-28% of the adult population and more than 50% of obese people all over the world. Modulation of the fatty acids in diet as a means of prevention against nonalcoholic fatty liver disease in animal models (NAFLD) remains unclear. The treatment of NAFLD has not been described in specific guidelines so far. Thus, the justification for the study is to check modifications in macronutrients composition, fatty acids, in particular, play a significant role in the treatment of NAFLD regardless of weight loss. Aim: To investigate different vegetable oils in prevention and progression of NAFLD in animal models. Methods: For the experiment were used fifty C57BL/6J mice male fed with high fat and fructose diet (HFD) to induce the NAFLD status and they received different commercial vegetable oils for 16 weeks to prevent steatosis. Liver steatosis and oxidative stress parameters were analyzed using biochemical and histological methods. Fatty acids profile in the oils and in the liver samples was obtained. Results: The high fat and fructose diet led to obesity and the vegetable oils offered were effective in maintaining body weight similar to the control group. At the end of the experiment (16 weeks), the HFHFr group had a greater body weight compared to control and treated groups (HFHFr: 44.20 ± 2.34 g/animal vs. control: 34.80 ± 3.45 g/animal; p < 0.001; HFHFr/OL: 35.40 ± 4.19 g/animal; HFHFr/C: 36.10 ± 3.92 g/animal; HFHFr/S: 36.25 ± 5.70 g/animal; p < 0.01). Furthermore, the HFD diet has caused an increase in total liver fat compared to control (p < 0.01). Among the treated groups, the animals receiving canola oil showed a reduction of hepatic and retroperitoneal fat (p < 0.05). These biochemical levels were positively correlated with the hepatic histology findings. Hepatic levels of omega-3 decreased in the olive oil and high fat diet groups compared to the control group, whereas these levels increased in the groups receiving canola and soybean oil compared to control and the high fat groups. Conclusion: In conclusion, the commercial vegetable oils either contributed to the prevention or reduction of induced nonalcoholic fatty liver with high fat and fructose diet, especially canola oil.

High Dose of A Conjugated Linoleic Acid Mixture Increases Insulin Resistance in Rats Fed Either A Low Fat or A High Fat Diet.

Obesity and related diseases are becoming more prevalent. Conjugated linoleic acid (CLA) might be a useful coadjutant treatment helping to decrease fat mass. However, the precise impact of CLA is unclear because the decreased body fat mass is followed by an increase in insulin resistance. This study aimed to evaluate some of the consequences of a high dose of CLA in rats fed a normal low fat or a high fat diet for 30 days. Male Wistar rats were separated into 4 groups (each n = 10): Control group receiving 7% fat (soybean oil); CLA group receiving 4% soybean oil and 3% CLA mixture; animal fat (AF) group, receiving 45% fat (lard); and animal fat plus CLA (AF+CLA) group, receiving 42% lard and 3% CLA mixture. The CLA mixture contained 39.32 mole% c9,t11-CLA and 40.50 mole% t10,c12-CLA. After 30 days, both CLA groups (CLA and AF+CLA groups) developed insulin resistance, with an increase in glucose in the fasting state and in an insulin tolerance test. The CLA group had increased liver weight and percentage of saturated fatty acids in liver and adipose tissue. Feeding the high fat diet resulted in increased hepatic triacylglycerol accumulation and this was exacerbated by dietary CLA. It is concluded that a high dose of CLA mixture increases insulin resistance and exacerbates hepatic steatosis when combined with a high fat diet.

Effect of Multicomponent Training on Blood Pressure, Nitric Oxide, Redox Status, and Physical Fitness in Older Adult Women: Influence of Endothelial Nitric Oxide Synthase (NOS3) Haplotypes.

The purpose of this study was to verify the influence of the genotype or haplotype (interaction) of the NOS3 polymorphisms [-786T>C, 894G>T (Glu298Asp), and intron 4b/a] on the response to multicomponent training (various capacities and motor skills) on blood pressure (BP), nitrite concentration, redox status, and physical fitness in older adult women. The sample consisted of 52 participants, who underwent body mass index and BP assessments. Physical fitness was evaluated by six-minute walk, elbow flexion, and sit and stand up tests. Plasma/blood samples were used to evaluate redox status, nitrite concentration, and genotyping. Associations were observed between isolated polymorphisms and the response of decreased systolic and diastolic BP and increased nitrite concentration and antioxidant activity. In the haplotype analysis, the group composed of ancestral alleles (H1) was the only one to present improvement in all variables studied (decrease in systolic and diastolic BP, improvement in nitrite concentration, redox status, and physical fitness), while the group composed of variant alleles (H8) only demonstrated improvement in some variables of redox status and physical fitness. These findings suggest that NOS3 polymorphisms and physical training are important interacting variables to consider in evaluating redox status, nitric oxide availability and production, and BP control.

Skin changes in streptozotocin-induced diabetic rats.

Diabetes can cause serious health complications, which can affect every organ of the body, including the skin. The molecular etiology has not yet been clarified for all diabetic skin conditions. Thus, this study aimed to investigate the changes of diabetes in skin compared to non-diabetic skin in rats. Fifteen days after establishing the diabetic status, skin samples from the dorsum-cervical region were harvested for subsequent analysis of alterations caused by diabetes. Our results demonstrate that diabetes stimulated higher inflammation and oxidative stress in skin, but antioxidant defense levels were lower compared to the non-diabetic group (p < 0.05). This could have been related to a decreased number of blood vessels and low expression of VEGF, eNOS and TGF-ß1. Finally, insulin signaling proteins IRS, Akt, Shc and ERK showed a low expression in the diabetic group. Thus, our study shows that the pathology of diabetes induced immunohistopathological and biochemical skin changes compared to non-diabetic skin in rats.

Protective effect of treatment with thiamine or benfotiamine on liver oxidative damage in rat model of acute ethanol intoxication.

AIMS: The aim of this study was to evaluate possible beneficial effects of treatment with thiamine or benfotiamine in an animal model of acute ethanol intoxication. MAIN METHODS: Thirty male Wistar rats were separated at random into three groups of 10 animals each: Ethanol (E), Ethanol treated with thiamine (T) and Ethanol treated with benfotiamine (BE). Rats were gavaged with single dose of ethanol (5g/kg, 40% v:v). After 30min of ethanol gavage the animals were treated with thiamine or benfotiamine. Six hours after first gavage, the animals were euthanized and blood and liver samples were collected for ethanol and oxidative stress biomarkers quantification. KEY FINDINGS: Serum ethanol levels were higher in animals treated with thiamine or benfotiamine while hepatic alcohol levels were higher in animals of the group treated with benfotiamine comparing to controls or thiamine treated groups. The lipid peroxidation biomarkers were diminished for the groups treated with thiamine or benfotiamine comparing to E animals. Concerning protein oxidative damage parameters, they were enhanced for animals treated with benfotiamine in relation to other groups. SIGNIFICANCE: In conclusion, the treatment with thiamine or benfotiamine even 30min after the massive dose of ethanol has proven to be beneficial against liver damage. Improved results were obtained with benfotiamine in relation to oxidative damage from aqueous compartments.

Phototherapy improves wound healing in rats subjected to high-fat diet.

This study aimed to compare the phototherapy effects on wound healing in rats submitted to normal and high-fat diets. Thirty-six rats received normal lipidic diet (NL) and 36 high lipidic (HL) diet for 45 days. The nutritional status was measured by body mass, blood glucose, total cholesterol, and triglycerides levels. Four experimental groups were performed according light (L) therapy applied "on" or "off" (660 nm, 100 mW, 70 J/cm(2), 2 J) on 1.5-mm-punched dorsum skin wounds as NLL+, NLL-, HLL+, and HLL-. The wound healing rate (WHR) and oxidative stress markers were analyzed on 2nd, 7th, and 14th days. Despite no difference among body mass, the HL rats presented higher blood glucose, total cholesterol, and triglycerides levels than NL rats. Respectively, on the 2nd and 14th days, the HLL+ group presented the highest WHRs (0.38 ± 0.16/0.97 ± 0.02) among all groups, while the HLL- (-0.002 ± 0.12/0.81 ± 12.1) the lowest WHRs. Hydroxyproline level was lower in HLL- (6.41 ± 1.09 µg/mg) than HLL+ (7.71 ± 0.61 µg/mg) and also NLL+ (9.33 ± 0.84 µg/mg). HLL+ presented oxidative stress markers similar to normal control group (NLL-) during follow up and highest antioxidant defense on 7th day. The results showed phototherapy accelerated the cutaneous wound healing by modulating oxidative stress in rats with metabolic disorders under a high-fat diet.

Oxidative stress and fatty acid profile in Wistar rats subjected to acute food restriction and refeeding with high-fat diets.

PURPOSE: To assess oxidative stress and the profile of fatty acids incorporated into the hepatic tissue of animals refed with high-fat (HF) diets after acute food restriction. METHODS: Fifty male Wistar rats were divided into five groups and fasting for 48 hours. One group was sacrificed without refeeding (NR), a control group (C) was refed with the standard AIN-93 diet and the remaining groups with HF diets respectively consisting of hydrogenated vegetable oil (PHVO), trans-free (TF) margarine and trans-free margarine enriched with ω-3 and ω-6 (O). After this period the animals were sacrificed for malondialdehyde (MDA), catalase and hepatic fatty acid determination. RESULTS: The groups refed with HF diets showed elevation of MDA levels compared to the C group (p<0.001 for GVH and p<0.01 for TF and O). Hepatic catalase activity was higher in the TF and O groups compared to group C (p<0.05 for both). The amount of saturated fatty acids was lower in the PHVO and O groups compared to the remaining ones (p<0.001). CONCLUSION: The consumption of high-fat diets after prolonged fasting favors oxidative imbalance in hepatic tissue.

Oxidative stress and fatty acid profile in Wistar rats subjected to acute food restriction and refeeding with high-fat diets

To assess oxidative stress and the profile of fatty acids incorporated into the hepatic tissue of animals refed with high-fat (HF) diets after acute food restriction. METHODS: Fifty male Wistar rats were divided into five groups and fasting for 48 hours. One group was sacrificed without refeeding (NR), a control group (C) was refed with the standard AIN-93 diet and the remaining groups with HF diets respectively consisting of hydrogenated vegetable oil (PHVO), trans-free (TF) margarine and trans-free margarine enriched with ω-3 and ω-6 (O). After this period the animals were sacrificed for malondialdehyde (MDA), catalase and hepatic fatty acid determination. RESULTS: The groups refed with HF diets showed elevation of MDA levels compared to the C group (p<0.001 for GVH and p<0.01 for TF and O). Hepatic catalase activity was higher in the TF and O groups compared to group C (p<0.05 for both). The amount of saturated fatty acids was lower in the PHVO and O groups compared to the remaining ones (p<0.001). CONCLUSION: The consumption of high-fat diets after prolonged fasting favors oxidative imbalance in hepatic tissue.

Metabolic parameters of postmenopausal women after quinoa or corn flakes intake--a prospective and double-blind study.

A prospective and double-blind study was conducted on 35 women with weight excess who consumed 25 grams of quinoa flakes (QF) or corn flakes (CF) daily during a period of four consecutive weeks. At the beginning (T1) and at the end (T2) of the intervention, total calorie intake was evaluated, anthropometric assessment was performed, blood was collected for the determination of glucose, total cholesterol and fractions, oxidative stress markers, vitamin E and enterolignans. Significant reductions were detected in serum triglyceride (CF group = 133.9 ± 89.4 to 113.7 ± 57 mg/dl and QF group = 112.3 ± 35 to 107.9 ± 33.1 mg/dl), TBARS (CF group = 3.2 ± 0.8 to 2.9 ± 0.5 µmol/l and QF group = 3.06 ± 0.6 to 2.89 ± 0.5 µmol/l) and vitamin E concentrations (CF group = 19.5 ± 5 to 17.9 ± 4 µM and QF group = 17.9 ± 4 to 16.9 ± 3 µM) and an increase in urinary excretion of enterolignans (CF group = 2.05 ± 1.3 to 2.24 ± 1.4 nm/ml and QF group = 2.9 ± 1.6 to 3.2 ± 2.7 nm/l), in both study groups. The reduction of total cholesterol (191 ± 35 to 181 ± 28 mg/dl) and LDL-cholesterol (LDL-c) (129 ± 35 to 121 ± 26 mg/dl), and the increase in GSH (1.78 ± 0.4 to 1.91 ± 0.4 µmol/l) occurred only in the QF group, showing a possible beneficial effect of QF intake.

Association of body fat with inflammation in peritoneal dialysis.

Peritoneal dialysis (PD) frequently leads to body weight gain, which appears to be a potential cause of the chronic inflammation frequently present in these patients. The consequences of this inflammation are impaired nutritional status, accelerated atherosclerosis, and increased mortality. To assess the association between inflammation and body fat in female patients treated with PD. Nineteen female patients on PD for at least 6 months with no infectious complications or malignant or acute inflammatory diseases. Nutritional status was determined by measuring weight, height, body mass index (BMI), waist (WC), and mid-arm circumferences (MAC), mid-arm muscle area, and tricipital fold (TCF). Bioelectrical impedance (BIA) was used to determine body composition. Biochemical evaluation included the determination of serum albumin, urea, creatinine, and C-reactive protein (CRP). The glucose absorbed from the dialysis solution was quantitated. According to BMI, two patients were classified as malnourished and ten as overweight/obese. Sixteen individuals had high WC measurements and 12 had excess body fat (BF) as measured by BIA. High CRP levels were observed in 12 patients, who had higher WC, MAC, BMI, TCF, and BF measurements compared to non-inflamed patients. Positive associations were detected between CRP and BMI, MAC, WC, and TCF. Associations between BF and CRP suggest that adiposity may be a potent exacerbating factor of inflammation in this population, especially visceral fat. Thus, obesity may be considered to be one more factor responsible for the early atherosclerosis and high cardiovascular mortality observed in these patients.

Association between hepatic cholesterol and oleic acid in the liver of rats treated with partially hydrogenated vegetable oil / Associação entre colesterol hepático e ácido oleico no fígado de ratos tratados com gordura vegetal parcialmente hidrogenada

OBJECTIVE: The aim of the present study was to investigate the lipid profiles of the hepatic and adipose tissues of Wistar rats treated for 21 days with a diet high in saturated fat (high saturated fat, n=6) or high in hydrogenated fat, that is, having 50% partially hydrogenated vegetable oil in its composition (high hydrogenated fat, n=6), and compare them to those of a control group (control group, n=6). METHODS: Adipose tissue and total hepatic fat were higher in the saturated fat group than in the hydrogenated fat group. Hepatic lipid peroxidation was greatest in the saturated fat group, with consequent lower hepatic vitamin E and A levels. In contrast, serum vitamin A was highest in the saturated fat group. Analysis of hepatic lipid fractions found more cholesterol and less high density lipoprotein-cholesterol in the hydrogenated fat group. The hydrogenated fat group had the highest levels of triacylglycerols, followed by the saturated fat group. RESULTS: Significant amounts of trans fatty acids were detected in the hepatic and adipose tissues of the hydrogenated fat group. Among the identified fatty acids, 18:1n9 had a higher positive association with hepatic cholesterol and triacylglycerols, and a higher negative association with high density lipoprotein-cholesterol. Partially hydrogenated vegetable oil promotes greater accumulation of cholesterol and triacylglycerols in the liver than saturated fats. CONCLUSION: Trans fatty acids were incorporated into hepatocytes and adipocytes in a highly efficient manner.

OBJETIVO: Esta pesquisa investigou a composição lipídica dos tecidos hepático e adiposo de ratos Wistar tratados durante 21 dias com uma dieta rica em gordura saturada (grupo gordura saturada, n=6) ou rica em gordura hidrogenada, ou seja, 50% da gordura consistindo de gordura vegetal parcialmente hidrogenada (grupo gordura hidrogenada, n=6) e compará-los a um grupo-controle (grupo-controle, n=6). MÉTODOS: As quantidades de tecido adiposo e gordura hepática total foram maiores no grupo gordura saturada do que no grupo gordura hidrogenada. A peroxidação lipídica hepática foi maior no grupo gordura saturada, com consequente diminuição dos níveis hepáticos de vitaminas E e A. Por outro lado, o nível sérico de vitamina A foi maior no grupo gordura saturada do que nos outros grupos. A análise das frações lipídicas hepáticas revelou mais colesterol e menos colesterol da lipoproteína de alta densidade no grupo gordura hidrogenada. O grupo gordura hidrogenada apresentou os maiores níveis de triglicérides, seguido do grupo gordura saturada. Quantidades significativas de ácidos graxos trans foram detectados nos tecidos hepático e adiposo do grupo gordura hidrogenada. RESULTADOS: Dentre os ácidos graxos identificados, o 18:1n9 apresentou uma associação positiva maior com o colesterol hepático e triglicérides, e uma associação negativa maior com o colesterol da lipoproteína de alta densidade. A gordura vegetal parcialmente hidrogenada promove um maior acúmulo de colesterol e triglicérides no fígado do que a gordura saturada. CONCLUSÃO: Os ácidos graxos trans foram incorporados aos hepatócitos e adipócitos de forma altamente eficiente.

Protein oxidative stress and dyslipidemia in dialysis patients.

Our aim was to investigate and determine the associations between oxidative stress (OS), dyslipidemia and inflammation in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) using observational cross-sectional study. Twenty patients in CAPD and 48 in HD for at least 8 weeks and aged ≥18 years were included in the study. Individuals with malignant or acute inflammatory disease were excluded. A control group of 17 healthy individuals was also recruited. The biochemical parameter evaluations were analyzed using colorimetric kits for albumin, serum glucose, total cholesterol (TC) and lipid fractions. To determine the inflammatory status, CRP, IL-6 and TNF-α were analyzed by automated chemiluminescence kits. Plasma advanced oxidation protein products (AOPP) were determined by spectrophotometry. Mean AOPP levels were significantly higher for the HD group compared to the control, and there was no difference in AOPP concentrations between the control and CAPD groups. Dialysis patients had levels of inflammatory parameters higher than controls, and showed a high prevalence of patients with dyslipidemia, especially in CAPD. In the HD group, AOPP was positively correlated with triglycerides (TG) and inversely associated with HDL. Also the HD group was observed to have negative associations between TNF-α and HDL, LDL and TC. In the CAPD group, CRP was inversely correlated with HDL. Hemodialysis patients had increased protein OS and associations of inflammation and dyslipidemia were also observed in these dialysis groups. A more detailed characterization of the relations between oxidative stress and other more traditional risk factors has therapeutic importance, since cardiovascular diseases are the leading cause of death among dialysis patients.