Sargassum muticum Hydrothermal Extract: Effects on Serum Parameters and Antioxidant Activity in Rats

Sargassum muticum was processed by hydrothermal extraction under previously optimized non-isothermal conditions (up to 187 °C). The alginate free crude hydrolysate was further concentrated by ultrafiltration, operating in diafiltration mode to produce an extract (SmE) enriched in the fucoidan and the phlorotannin fractions and with low mineral content and antiradical capacity equivalent to that of Trolox. In order to explore the potential of this concentrated product for food or feed additive, the in vivo antioxidant potential was assessed. Male Sprague–Dawley rats were fed SmE dissolved in distilled water at doses of 0.5, 1.0 or 2.0 g kg−1, administered via an intragastric tube daily for three weeks. The weight and organ gain was not significantly affected in the different groups in relation to the control group fed a standard diet. Serum glucose was significantly lowered in the groups receiving the higher SmE doses, liver GPx levels were reduced and liver TBARS levels decreased in rats administered the extract, but no effect on SOD activity in either liver or erythrocytes was observed.

The effects of hydraulic calcium silicate containing endodontic materials on oxidative stress in erythrocytes and liver

Objective: The aim of this study was to evaluate the effects of hydraulic calcium silicate endodontic cements, MTA Angelus, MTA Fillapex, and Theracal LC, on erythrocyte and liver oxidative stress parameters of rats. Methods: Right upper incisor of each rat was extracted and polyethylene tubes containing the dental cements, or left empty for the control group, were inserted into the extraction socket. Blood and liver samples of each animal were obtained after 7, 30, or 60 days. Thiobarbituric acid reactive substances (TBARS) levels and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were determined by spectrophotometry. Results: Erythrocyte and liver TBARS levels, and CAT and SOD enzymatic activities were significantly increased in dental cement applied groups compared with controls on day 7. The highest erythrocyte and liver TBARS concentrations were observed in the MTA Angelus group on day 7 of exposure. On day 30, erythrocyte CAT activity remained markedly high, but the other parameters returned to almost normal levels. On day 60, all parameters were similar between the control and the experimental groups. Conclusions: This is the first study to show that TBARS levels and antioxidant enzyme activities are transiently increased as a result of dental cement application.

In Vivo Subacute Toxicity and Antidiabetic Effect of Aqueous Extract of Nigella sativa

Context. Nigella sativa seeds are usually used as traditional medicine for a wide range of therapeutic purposes. Objective. To investigate the subacute toxicity of NS aqueous extract and select its lowest dose to study its antidiabetic effect. Methods. 5 AqE.NS doses (2, 6.4, 21, 33, and 60 g/Kg) were daily administered to mice by gavage. Biochemical parameters measurements and histological study of the liver and the kidney were performed after 6 weeks of supplementation. Thereafter, and after inducing diabetes by alloxan, rats were treated by 2 g/Kg of AqE.NS during 8 weeks. Metabolic parameters were measured on sera. A horizontal electrophoresis of plasmatic lipoprotein was conducted. Glycogen, total lipids, and triglycerides were measured in the liver. TBARS were evaluated on adipose tissue, liver, and pancreas. Results. AqE.NS showed no variation in urea and albumin at the 5 doses, but hepatotoxicity from 21 g/Kg was confirmed by histopathological observations of the liver. In diabetic rats, AqE.NS significantly decreased glycemia, TG, T-cholesterol, LDL-c, and TBARS and showed a restored insulinemia and a significant increase in HDL-c. Results on the liver indicated a decrease in lipids and a possible glycogenogenesis. Conclusion. AqE.NS showed its safety at low doses and its evident antihyperglycemic, antihyperlipidemic, and antioxidant effect.

Functioning of the antioxidant system of rat tissues poisoned with heavy metals

To investigate the functioning of antioxidant system in blood and liver of rats, poisoned of heavy metals (copper sulfate, zinc sulfate, cadmium sulfate and lead nitrate) on lipid peroxidation and on activity of glutathione-dependent enzymes of blood and liver of poisoned rats are shown in this article. It is shown that the introduction of heavy metals in rats leads to an increase in blood and liver TBARS-products and diene conjugates. Under the action of heavy metals decreases the activity of catalase and superoxide dismutase. A reduction in the activity of glutathione peroxidase and glutathione transferase under the influence of high doses of heavy metals. Under the action of heavy metals reduced glutathione content in rat tissues.

Protective effects of Gingko biloba on thioacetamide-induced fulminant hepatic failure in rats

Gingko biloba (GB) has antioxidant and platelet-activating factor (PAF) antagonistic effects. We investigated the protective effects of GB on thioacetamide (TAA)induced fulminant hepatic failure in rats. Fulminant hepatic failure was induced in treatment groups by three intraperitoneal (ip) injections of TAA (350 mg/kg) at 24-hour intervals. Treatments with GB (100 mg/kg per day, orally) and N-acetylcysteine (20 mg/kg twice daily, sc) were initiated 48 hours prior to TAA administration. The liver was removed for histopathological examinations. Serum and liver thiobarbituric acid-reactive substance (TBARS) levels were measured for assessment of oxidative stress. Liver necrosis and inflammation scores and serum and liver TBARS levels were significantly higher in the TAA group compared to the control group (P <0.001,<0.001, 0.001,<0.001, respectively). Liver necrosis and inflammation scores and liver TBARS levels were significantly lower in the GB group compared to the TAA group (P <0.001,<0.001 and 0.01, respectively). GB ameliorated hepatic damage in TAA-induced fulminant hepatic failure. This may be due to the free radical-scavenging effects of GB.

Thermally oxidised sunflower-seed oil increases liver and serum peroxidation and modifies lipoprotein composition in rats

Peroxidation of LDL and other lipoproteins is thought to play a central role in atherogenesis. Dietary thermally oxidised oils may increase atherogenic risk in consumers by increasing their oxidative status. The present paper compares the effects of two diets containing unused sunflower-seed oil (US) or sunflower-seed oil repeatedly used in frying (FS) (both 15 g/100 g diet) on weight gain, food efficiency ratio, serum lipid levels and lipoprotein composition, and the content of thiobarbituric acid-reactive substances (TBARS) in the liver, serum, and lipoproteins in growing Wistar rats. After sixty potato fryings the FS contained 27·7 g polar material/100 g oil and 16·6 g oligomers/100 g oil. The FS-fed rats had a significantly lower weight gain and food efficiency ratio. Liver-TBARS increased due to the consumption of the highly altered oil and showed a significant linear relationship (all r<0·68; P>0·002) with the ingestion of thermally oxidised compounds. Serum-, VLDL-, LDL- and HDL-TBARS were significantly higher in the FS-fed rats (all P>0·001). Concentrations of serum total and non-esterified cholesterol and phospholipids were significantly higher in the FS-fed rats (P>0·05, P>0·05, and P>0·001, respectively). Serum triacylglycerol concentrations did not vary between the two dietary groups. Total and esterified cholesterol and phospholipid levels increased significantly in the HDL fraction (P>0·05, P>0·05, and P>0·001, respectively) of the FS-fed rats. HDL-cholesterol and HDL-phospholipids were significantly correlated with liver-TBARS (r<0·747; P>0·0001), VLDL-TBARS (r<0·642; P>0·003), LDL-TBARS (r<0·475; P>0·04), and HDL-TBARS (r<0·787; P>0·0001). The data suggest that the rat increases HDL as a protecting mechanism against the peroxidative stress induced by the consumption of a diet containing the thermally oxidised oil.

EFFECTS OF SATURATED AND UNSATURATED FATS WITH VITAMIN E SUPPLEMENTATION ON THE ANTIOXIDANT STATUS OF BROILER CHICKEN TISSUES

The influence of fish oil (highly unsaturated) and beef tallow (highly saturated) with vitamin E (100 IU/kg) supplementation on the antioxidant status of broiler chicken cockerels was investigated. Chicks were fed a control diet with no added fat, 40 g/kg each of fish oil and beef tallow diets, respectively, from 11 to 42 days of age. Tocopherol concentration and the rate of lipid peroxidation, thiobarbituric acid reactive substance (TBARS) in liver, fatty acid composition of the liver lipids, blood serum total antioxidant status (TAS), and reduced glutathione (GSH) content were determined. Vitamin E supplementation of the diet increased liver ?-tocopherol content in chicks regardless of the type of dietary fat. Fish oil diet resulted in higher liver TBARS value while beef tallow diet showed lower values compared to the control diet. Vitamin E supplementation reduced liver TBARS as well as serum GSH, and raised serum TAS for all diets. Serum GSH was the same for vitamin E supplemented diets regardless of the fat supplement. Fish oil diets resulted in a significant increase in hepatic lipid n-3 PUFA content. A significant positive correlation was found between liver TBARS and n-3 PUFA content. No relationships were established, however, between liver TBARS and n-6 PUFA or saturated fatty acids. The results suggest that feeding oils rich in n-3 PUFA increases tissue concentration of these fatty acids, consequently increasing tissue lipid peroxidation and reducing the antioxidative status of broiler chickens. Supplementing high levels of vitamin E with such oils may increase tissue oxidative stability. Serum TAS or GSH may be used as a measure of antioxidative status in chickens.