Assessment of a natural dietary extract, titrated in phenylpropanoid glycosides, on blood parameters and plasma oxidative status in intensively reared Italian hares (Lepus corsicanus)

Two different doses of a natural extract titrated in phenylpropanoid glycosides (PPGs) were evaluated for their effect on blood parameters and plasma oxidative status in pairs of intensively reared Italian hares. The study lasted 210 days, during which 45 couples of hares were divided into three homogeneous groups. A control group (CON) was fed a control diet while the two experimental groups were fed a diet supplemented with 1 or 2 kg/t of a supplement titrated in PPGs. Blood samples were obtained at 0, 70, 140 and 210 days and assayed for plasma lipid profiles, bilirubin, haematological parameters and indicators of oxidative status (reactive oxygen metabolites (ROMs), thiobarbituric acid reactive substances (TBARS), vitamins A and E). Although dietary treatment did affect the levels of triglycerides, total cholesterol and total bilirubin, all of which decreased markedly (P < 0.05), while significantly increasing the (P < 0.01) HDL cholesterol values, it also significantly improved the oxidative status of the blood, which displayed an increase in both vitamin E (P < 0.01) and vitamin A (P < 0.05) and a decrease in ROMs (P < 0.01) and TBARS (P < 0.05). The improvements in the blood parameters, lipid profile and plasma oxidative status continued to increase significantly as the trial progressed, indicating a positive effect with increased length of treatment. The results of this study demonstrate an important role for feed supplementation with respect to antioxidant activity on some blood parameters, including the lipid profile and the oxidative status of blood.     

Protective role of intraperitoneally administered vitamin E and selenium on the antioxidative defense mechanisms in rats with diabetes induced by streptozotocin

The aim of this work was to determine the protective effects of intraperitoneally administered vitamin E and selenium (as Na₂SeO₃, Se) on the lipid peroxidation as thiobarbituric acid reactive substances (TBARS) and vitamin E levels, glutathione peroxidase (GSH-Px), reduced glutathione (GSH) activities in the plasma, red blood cell (RBC), liver, and muscle of rats with streptozotocin-induced diabetes. Fifty adult male Wistar rats were used and all rats were randomly divided into five groups. The first group was used as a control and the second group as a diabetic control. A placebo was given to first and second groups by injection. The third group was intraperitoneally administered with vitamin E (20 mg over 24 h), the fourth group with Se (0.3 mg over 24 h), and the fifth group with vitamin E and Se combination (COM) (20 mg vitamin E + 0.3 mg Se over 24 h). This administration was done for 25 days and the TBARS, vitamin E, GSH-Px, GSH levels in the plasma, RBC, liver, and muscle samples were determined. The vitamin E level in the plasma and liver was significantly (p < 0.05) higher in the control than in the diabetic control group. Also, the TBARS levels in the RBC, liver, and muscle were significantly (p < 0.05) lower in the control than in the diabetic control group. However, GSH-Px and GSH activities in RBC, liver, and muscle were not statistically different between the control and the diabetic control groups. The vitamin E levels in plasma and liver (p < 0.01 and p < 0.001) and GSH-Px activities (p < 0.01, p < 0.001) in RBC were significantly higher in vitamin E, Se, and COM groups than in both control and diabetic control groups. However, the TBARS levels of RBC, muscle, and liver in vitamin E and Se administered groups were significantly (p < 0.05-p < 0.001, respectively) decreased. These results indicate that intraperitoneally administered vitamin E and Se have significant protective effects on the blood, liver, and muscle against oxidative damage of diabetes. The abstract of this study was presented in Physiological Research 48(Suppl. 1), S99 (1999).     

Impact of Hemidesmus indicus R.Br. extract on ethanol-mediated oxidative damage in rat kidney

The antioxidant effect of the ethanolic extract of Hemidesmus indicus R.Br. root (EHI), an indigenous Ayurvedic medicinal plant in India, was studied in rats with ethanol-induced nephrotoxicity. Administering 5 g/kg body weight/day of ethanol for 60 days to male Wistar rats resulted in significantly elevated levels of serum urea, creatinine and uric acid as well as kidney thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH) and conjugated dienes (CD) as compared to those of the experimental control rats. Decreased levels of kidney superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), vitamin C and vitamin E were also observed on alcohol administration as compared with those of the experimental control rats. EHI was administered at a dose of 500 mg/kg body weight/day for the last 30 days of the experiment to rats with ethanol-induced kidney injury, which significantly decreased the levels of serum urea, uric acid and creatinine as well as kidney TBARS, LOOH and CD and significantly elevated the activities of SOD, CAT, GPx, GSH, vitamin C and vitamin E in kidney as compared to that of untreated ethanol-administered rats. Histopathological observations also correlated with the biochemical parameters. Thus, the data indicate that treatment with EHI offers protection against free radical-mediated oxidative stress in kidney of animals with ethanol-induced nephrotoxicity.     

Response to oxidative stress as a welfare parameter in swine

In pigs, the genetic selection for lean, large muscle blocks and fast growth has been linked to an increased prevalence of metabolic diseases such as porcine stress syndrome and mulberry heart disease. These diseases are associated with cardiovascular inadequacy, which may lead to oxidative stress. In the present study, reactive oxygen metabolites (ROMs) and the anti-oxidant power (OXY) in sera of different swine groups were investigated. The following groups were selected (each around 80 kg body weight): wild boars (WB), Cinta Senese (CS), and Landrace x Large White (LxLW), the latter as both specific pathogen-free (SPF) and intensively farmed animals. In addition, a group of LxLW agonic sows (AS) was also investigated; this group is known to be under oxidative stress. Two colorimetric micro-methods were used to measure ROMs and OXY; ROMs were expressed as mM H(2)O(2) and OXY as microM HOCl neutralised. Between groups, average ROM and OXY values were found to be significantly different by one-way ANOVA (P < 0.001). ROM levels were lower in WB (13.41 +/- 1.85) and CS (19.27 +/- 1.68), and highest in LxLW (42.00 +/- 1.36). OXY values ranged from 260.10 +/- 22.13 (WB) to 396.90 +/- 9.83 (LxLW). Only one swine group (the CS group) showed a significant, positive correlation between ROM and OXY values. The AS group even showed a negative correlation between ROM and OXY values. These results imply satisfactory environmental coping occurred only within the CS group. Results are discussed in the light of animal welfare legislation, food safety and consumers' protection.     

Oxidative status and semen characteristics of rabbit buck as affected by dietary vitamin E,C and n-3 fatty acids

The aim of this study was to investigate the effect of dietary supplementation of long chain fatty acids (C > or = 20 LCP) of the n-3 series, vitamin E and vitamin C on the antioxidant capacity of rabbit buck and on semen characteristics. Fifty male rabbits at 30 days were randomly assigned to five different diets: Control (50 mg x kg(-1) diet alpha-tocopheryl acetate), Vitamin E (200 mg x kg(-1) diet alpha-tocopheryl acetate), n-3 (2% ROPUFA oil + 50 mg x kg(-1) diet alpha-tocopheryl acetate), n-3 + E (2% ROPUFA oil + 200 mg x kg(-1) diet alpha-tocopheryl acetate) and n-3 + E C (2% ROPUFA oil + 200 mg x kg(-1) diet alpha-tocopheryl acetate + 0.5 g x L(-1) vitamin C in the drinking water). The levels of vitamins E and C and reactive oxygen metabolites (ROMs) in the blood plasma were evaluated at different ages. The antioxidant capacity and ROMs of seminal plasma, the fatty acid profile of sperm phospholipids, the semen traits and the oxidative processes during storage (24 h at + 4 degrees C) were carried out weekly for 5 wk starting from the 5th month of age. Vitamin E addition showed enough antioxidant protection only when associated with no lipid enriched diets. The n-3 supplementation modified the fatty acid profile of the spermatozoa membrane and simultaneously enhanced oxidative processes. Only the association with supranutritional levels of vitamins E and C inhibited the oxidative processes and improved the characteristics of fresh and stored rabbit semen.     

Impact of Hemidesmus indicus R.Br. extract on ethanol-mediated oxidative damage in rat kidney

Abstract

The antioxidant effect of the ethanolic extract of Hemidesmus indicus R.Br. root (EHI), an indigenous Ayurvedic medicinal plant in India, was studied in rats with ethanol-induced nephrotoxicity. Administering 5 g/kg body weight/day of ethanol for 60 days to male Wistar rats resulted in significantly elevated levels of serum urea, creatinine and uric acid as well as kidney thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH) and conjugated dienes (CD) as compared to those of the experimental control rats. Decreased levels of kidney superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), vitamin C and vitamin E were also observed on alcohol administration as compared with those of the experimental control rats. EHI was administered at a dose of 500 mg/kg body weight/day for the last 30 days of the experiment to rats with ethanol-induced kidney injury, which significantly decreased the levels of serum urea, uric acid and creatinine as well as kidney TBARS, LOOH and CD and significantly elevated the activities of SOD, CAT, GPx, GSH, vitamin C and vitamin E in kidney as compared to that of untreated ethanol-administered rats. Histopathological observations also correlated with the biochemical parameters. Thus, the data indicate that treatment with EHI offers protection against free radical-mediated oxidative stress in kidney of animals with ethanol-induced nephtrotoxicity.     

Influence of ferulic acid on circulatory prooxidant-antioxidant status during alcohol and PUFA induced toxicity.

In recent years, there has been an escalation in alcohol abuse and inevitably, alcohol related disorders are becoming an increasingly important cause of morbidity and mortality. Alcohol is known to induce a dose dependent increase in lipid peroxidation. Alcohol related disabilities are more pronounced when taken along with diet rich in polyunsaturated fatty acid (PUFA). The present work aims at analysing the protective role of ferulic acid (FA), a naturally occurring nutritional component on alcohol and PUFA induced oxidative stress. Two different doses of ferulic acid, 20 mg/kg body weight and 40 mg /kg body weight were used for the study. The results showed that the levels of oxidative markers; thiobarbituric acid reactive substances (TBARS), hydroperoxides (HP) and levels of copper (Cu) and ferritin were increased significantly in plasma of alcohol, thermally oxidised PUFA (DeltaPUFA) and alcohol + DeltaPUFA groups, which were decreased significantly on treatment with both the doses of ferulic acid. The activities of enzymic antioxidants viz. superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and non enzymic antioxidants like vitamin C, vitamin E, and reduced glutathione (GSH) and the levels of zinc (Zn) were significantly decreased in alcohol, DeltaPUFA and alcohol + DeltaPUFA groups which were improved significantly on treatment with both the doses of FA. The reduction in oxidative stress was more significant in 20 mg/kg body weight treatment groups compared to 40 mg/kg body weight. Thus from the results obtained, we conclude that FA effectively protects the system against alcohol and PUFA induced oxidative stress.     

Modulation of restraint stress induced oxidative changes in rats by antioxidant vitamins

In the present study we examined immobilization stress-induced antioxidant defense changes in rat plasma and also observed the antioxidant effects of pre and post vitamins A, E and C administration (15 mg/Kg of body weight) individually and in combination (vit E + C) on these alterations.Following immobilization stress the circulating activities of superoxide dismutase, catalase and glutathione-S-transferase were decreased, while the level of thiobarbituric acid reactive substances (TBARS) was increased as compared to non-stressed control rats.Post treatment with individual vitamins A, E and C (after exposure to stress) resulted in a less marked alteration of plasma TBARS levels and activities of SOD, GST and catalase as compared to pre vitamin stress or stress alone treatments. Both pre and post vitamin treatments were effective in preventing stress induced derangement of free radical metabolism with a relative dominance by latter. The combined treatment with vitamin E and C did not show any additive antioxidant effect on restraint stress induced altered free radical metabolism, rather a predominant effect similar to vitamin E alone was observed. The prevention of oxidative stress generated in response to restraint stress by the vitamins can be summarized as: vitamin (E + C) i.e. vit E > vit C > vit A, thus combined vitamin (E + C) treatment though showed maximum preventive effect, but was similar to vitamin E treatment alone, in terms of the circulating activities of SOD, GST, catalase and TBARS levels.     

Vitamin E attenuates biochemical and morphological features associated with development of chronic pancreatitis

The objective was to investigate the effects of vitamin E on collagen deposition induced by Cyclosporin A (CsA) administration in rats with caerulein (Cr) pancreatitis. CsA transforms the fully regenerative, self-limited form of Cr pancreatitis into a chroniclike disease in conjunction with increased transforming growth factor (TGF)-beta and myofibroblast proliferation. Vitamin E inhibits TGF-beta release in mesangial cells and reduces CsA cytotoxicity. Wistar rats received CsA daily (20 mg/kg), and CR pancreatitis was induced on days 1 and 8 (Cr + CsA group). In a separate group, vitamin E (600 mg.kg(-1).day(-1)) was administered starting 4 days before CsA. Three other groups received either vehicle, CsA, or Cr alone. Thiobarbituric acid-reactive substance (TBARS), 8-isoprostanes, and hyaluronic acid were measured in plasma obtained on the day the animals were killed (day 15). Pancreases were weighed and processed for light microscopy to assess connective tissue and myofibroblast number. Pancreatic homogenates were also assayed for collagen (hydroxyproline) and TBARS content. TBARS, 8-isoprostane, and TGF-beta were elevated in CsA and Cr + CsA rats. Vitamin E treatment greatly decreased these parameters. Vitamin E also decreased the fall in pancreatic weight observed in Cr + CsA pancreas. Pancreatic hydroxyproline and plasma hyaluronic acid were increased in Cr + CsA rats but were effectively reduced by vitamin E. Morphology showed improvement in fibrosis score and a decreased number of myofibroblasts in vitamin E-treated rats. Vitamin E reduces oxidative stress and collagen deposition during the development of experimental chronic pancreatitis. Adjuvant antioxidants may be of value in the treatment of chronic pancreatitis.     

Effects of Vitamins, Probiotics, and Protein Level on Semen Traits and Some Seminal Plasma Macro- and Microminerals of Male Broiler Breeders After Zinc-Induced Molting

This study was conducted to investigate the effects of vitamin E, vitamin C, probiotics, dietary protein level, and their combination on semen traits and seminal plasma macro- and microminerals in 65-week-old male broiler breeders after zinc-induced molting. One hundred eighty birds were induced to molt by mixing zinc oxide (3,000 mg/kg) in the diet. The birds were divided into six groups (five replicates) by completely randomized design. One group was kept as control (16% CP), while the other five were supplemented with vitamin E (100 IU/kg feed), vitamin C (500 IU/kg feed) probiotics (50 mg/L), protein level (14% CP), and their combination. Semen samples were weekly collected for determination of semen volume, sperm concentration, motility, and dead sperm percentage. Analyses of Na, K, Ca and Mg, Zn, Fe, Mn, and Cu in seminal plasma were also performed. Overall, mean semen volume was significantly high in vitamin E and C supplemented groups compared to control. Overall mean sperm motility was significantly higher in vitamin E supplemented group, whereas dead sperm percentage was significantly lower in the vitamin C group compared to control. Mineral analyses revealed that overall mean seminal plasma Mg increased significantly in vitamin E and C supplemented groups compared to control. Similarly, significantly high overall mean seminal plasma Cu concentration was observed in vitamins E and C and combination groups. It can be concluded that vitamins have a vital role in improving semen quality and bioavailability of Mg and Cu in seminal plasma of the post-molt cockerels.     

Elevated muscle vitamin E does not attenuate eccentric exercise-induced muscle injury.

The purpose of this study was to evaluate the effect of elevated muscle vitamin E content on skeletal muscle damage from eccentric exercise. Sixty Sprague-Dawley rats were put on a normal (40 IU vitamin E/kg food) or supplemented (10,000 IU vitamin E/kg food) diet for 5 wk. Injury in soleus muscle was determined using several criteria: reductions in maximal tetanic force and number of intact fibers per square millimeter and elevations in muscle glucose 6-phosphate dehydrogenase activity and plasma creatine kinase activity, either immediately (0 h) or 2 days (48 h) after a downhill walking protocol. Sedentary animals were also tested but did not exercise. Muscle vitamin E levels were significantly elevated (approximately 3- to 4-fold), and susceptibility of the muscles to oxidant stress was decreased, after supplementation. However, vitamin E supplementation did not attenuate injury by any of the criteria employed. Maximal tetanic force decreased approximately 20% at 0 and 48 h after exercise in both groups. The number of intact fibers per square millimeter decreased approximately 30-35% in both groups at 0 and 48 h. Glucose 6-phosphate dehydrogenase activity increased approximately 50-100% in both groups at 48 h, and plasma creatine kinase activity was elevated approximately 2- to 2.5-fold at 0 h in both groups. These findings do not support a major role for free radical damage to muscle membranes in the initiation of injury from eccentric exercise, although they do not disprove free radical involvement in the etiology.     

Effect of cadmium on antioxidant status in alloxane-induced diabetic rats

Fifty-two healthy Swiss Male Albino rats aged two mo were used in this study. They were divided into four groups: control (C), diabetic (D), cadmium (Cd), and diabetic+Cd (D+Cd) groups. Diabetic condition was induced in D and D+Cd groups by administration of alloxane (5 mg/100 g). After this treatment, CD and D+Cd groups were injected with CdCl₂ ip (2 mg/kg/wk). At the end of the 2-mo experimental period, thiobarbituric acid reactive substances (TBARS), plasma and erythrocyte selenium (SE), plasma ceruloplasmin (Cp), and vitamin E (vit E) were determined in four groups of rats. The erythrocyte Se was lower in the experimental groups than in the controls. Plasma Se was significantly decreased in the D and D+Cd groups compared with the control group. Plasma Cp was unaltered. Plasma vit E was significantly decreased in Cd group in comparison with the C, D, and D+Cd groups.     

Distribution of Tocotrienols in Rats Fed a Rice Bran Tocotrienol Concentrate

To examine the distribution of rice bran tocotrienol (T3), we gave rice bran T3 to rats after considering an acceptable daily intake of vitamin E for humans. Male SD rats (5 weeks of age) were fed for 3 weeks on a commercial diet containing 6.4 mg of vitamin E per 100 g wt and additively received vitamin E or the vehicle (vitamin E-free corn oil) by oral intubation. The animals were randomly divided into 4 groups depending on the type of test diet: control (vehicle), non-T3 (no T3 + 4.3 mg of tocopherol (TOC)/kg body weight (b.w.)/day), low-T3 (0.8 mg T3 + 3.5 mg TOC/kg b.w./day), and high-T3 (3.2 mg T3 + 1.1 mg TOC/kg b.w./day). The control rats and rats in the non-T3, low-T3, and high-T3 groups took 4.3 and 8.6 mg of vitamin E/kg b.w./day, respectively. Rice bran γ-T3 was significantly distributed to the adipose tissue and increased from 1.1 to 10.2 nmol/g of adipose tissue according to the rice bran T3 intake.     

Distribution of tocotrienols in rats fed a rice bran tocotrienol concentrate

To examine the distribution of rice bran tocotrienol (T3), we gave rice bran T3 to rats after considering an acceptable daily intake of vitamin E for humans. Male SD rats (5 weeks of age) were fed for 3 weeks on a commercial diet containing 6.4 mg of vitamin E per 100 g wt and additively received vitamin E or the vehicle (vitamin E-free corn oil) by oral intubation. The animals were randomly divided into 4 groups depending on the type of test diet: control (vehicle), non-T3 (no T3 + 4.3 mg of tocopherol (TOC)/kg body weight (b.w.)/day), low-T3 (0.8 mg T3 + 3.5 mg TOC/kg b.w./day), and high-T3 (3.2 mg T3 + 1.1 mg TOC/kg b.w./day). The control rats and rats in the non-T3, low-T3, and high-T3 groups took 4.3 and 8.6 mg of vitamin E/kg b.w./day, respectively. Rice bran gamma-T3 was significantly distributed to the adipose tissue and increased from 1.1 to 10.2 nmol/g of adipose tissue according to the rice bran T3 intake.     

Influence of dietary vitamin E and C supplementation on vitamin E and C content and thiobarbituric acid reactive substances (TBARS) in different tissues of growing pigs

To investigate the influence and possible interactions of dietary vitamin E and C supplementation on vitamin content of both vitamins and oxidative stability of different pork tissues 40 Large White barrows from 25 kg to 106 kg were allocated to four different cereal based diets: Basal diet (B), dl-alpha-tocopherylacetate + 200 mg/kg (E), crystalline ascorbic acid + 300 mg/kg (C) or both vitamins (EC). At slaughtering samples of liver, spleen, heart, kidney, backfat outer layer, ham and M. tongissimus dorsi were obtained. Growth performance of the pigs and carcass characteristics were not influenced by feeding treatments. Dietary vitamin E supplementation had a significant effect on the vitamin E and alpha-tocopherol concentration in all investigated tissues. Backfat outer layer, liver, spleen, kidney and heart had higher vitamin E concentrations than ham and M. longissimus dorsi. Dietary vitamin C supplementation tended towards enhanced vitamin E levels except for ham samples. Therefore, some synergistic actions without dietary vitamin E supplementation between the two vitamins could be shown. The vitamin C concentration and TBARS were increased or at least equal in all tissues due to vitamin C supplementation. Dietary alpha-tocopherol supplementation resulted in lower TBARS in backfat outer layer (malondialdehyde 0.35 mg/kg in B vs. 0.28 mg/kg in E), but increased in heart and ham. When both vitamins were supplemented (EC) TBARS were lower in M. longissimus dorsi and backfat outer layer, equal in heart and higher in liver and ham compared to a single vitamin C supplementation. Rancimat induction time of backfat outer layer was 0.3 h higher in C compared to B and 0.17 h higher in EC than in E. Correlations between levels of both vitamins were positive for kidney (r = 0.169), M. longissimus dorsi (r = 0.499) and ham (r = 0.361) and negative for heart (r = -0.350). In liver and spleen no interaction could be found. In backfat outer layer vitamin E was positively correlated with rancimat induction time (r = 0.550) and negatively with TBARS (r = -0.202), but provided no evidence that dietary vitamin E supply led to better oxidative stability.     

Activity of Cassia auriculata leaf extract in rats with alcoholic liver injury

This study was undertaken to investigate the effect of Cassia auriculata leaf extract on tissue lipid peroxidation and antioxidant status in experimental hepatotoxicity. Administering ethanol to rats for 60 days resulted in significantly elevated levels of serum total bilirubin, aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) as compared with those of the experimental control rats. Significantly elevated levels of tissue thiobarbituric acid reactive substances (TBARS), hydroperoxides and lowered activities of superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) were also observed on alcohol treatment as compared with those of experimental control rats. Concentration of serum non-enzymic antioxidants such as vitamin E and vitamin C were also significantly lowered on alcohol supplementation. Treatment with Cassia auriculata leaf extract at a dose of 250 mg kg(-1) body weight and 500 mg kg(-1) body weight to rats administered alcohol, lowered the levels of TBARS and hydroperoxides and elevated the activities of SOD and CAT and the levels of reduced GSH in the liver, brain, kidney and intestine significantly compared to unsupplemented alcohol treated rats. Cassia auriculata leaf extract treatment restored the serum vitamin E, and vitamin C levels also to near those of the experimental control animals. Our data indicate that supplementation with Cassia auriculata leaf extract can offer protection against free radical mediated oxidative stress in experimental hepatotoxicity. In addition, histopathological studies of the liver and brain confirmed the beneficial role of Cassia auriculata leaf extract.     

Vitamin E requirements of juvenile grass shrimp, Penaeus monodon, and effects on non-specific immune responses

A feeding trial was conducted to determine the dietary vitamin E (DL-alpha-tocopheryl acetate, dl-alpha-TOA) requirement and its effect on the non-specific immune responses of juvenile grass shrimp, Penaeus monodon. Purified diets with eight levels (0, 25, 50, 75, 100, 150, 200, 400 mg vitamin E kg diet-1) of supplemental dl-alpha-TOA were fed to P. monodon (mean initial weight 0.29 +/- 0.01 g) for eight weeks. Each diet was fed to three replicate groups of shrimp. Weight gains and total haemocyte count (THC) were higher (P < 0.05) in shrimp fed diets supplemented with 75 and 100 mg vitamin E kg diet-1 than in shrimp fed diets supplemented with 相似文献   

Effect of selenium and vitamin E supplementation on lipid abnormalities in plasma, aorta, and adipose tissue of Zucker rats

Twenty-nine obese female Zucker rats (fa / fa) were fed with a laboratory chow supplemented or not with a selenium-rich yeast (Selenion), or Selenion + vitamin E, or vitamin E alone. Twelve lean female Zucker rats (Fa / Fa) of the same littermates fed with the same diet were used as control. After 32 wk of diet, obesity induced a large increase in plasma insulin and lipid levels. A significant decrease in the plasma vitamin E/triglycerides ratio (p < 0.005) and an increase in plasma thiobarbituric reactive substances (TBARS) (p < 0.005) were also observed. Plasma selenium and vitamin E increased in all supplemented rats. The plasma insulin level was decreased by selenion supplementation and the vitamin E/triglycerides ratio was completely corrected by double supplementation with Selenion + vitamin E. TBARS were also efficiently decreased in two obese groups receiving vitamin E. In plasma, adipose tissue and aorta, obesity induced an increase in palmitic acid (C16:0), a very large increase in monounsaturated fatty acids (palmitoleic acid C16:l, stearic acid C18:l) associated with a decrease in polyunsaturated n-6 fatty acids (linoleic acid C18:2 n - 6, arachidonic C20:4 n - 6). These alterations in fatty acid distribution were only partly modulated by Se and vitamin E supplements. However, in the aorta, antioxidant treatment in obese rats significantly reduced the increase in C16:0 and C16:l (p < 0.05 andp < 0.01, respectively) and the decrease in arachidonic acid (p < 0.05). These changes could be beneficial in the reduction of insulin resistance and help to protect the vascular endothelium.     

Effect of oat by-product antioxidants and vitamin E on the oxidative stability of pork from pigs fed diets supplemented with linseed oil

The aim of the experiment was to compare the antioxidative potential of an oat by-product with the effect of vitamin E on the oxidative stability of pork from pigs fed a diet enriched with linseed oil. Thirty-four crossbreed barrows were fed individually from 39 to 109 kg body weight (BW) on one of four diets: a control diet based on barley-triticale-soybean (Diet C), a diet containing an oat byproduct (Diet O), and the same diets supplemented with vitamin E (100 mg/kg diet) (Diets CE and OE, respectively). The oat by-product, comprising oat hulls and bran, was included at 10 and 20% in the grower and finisher diets, respectively. To Diets O and OE, refined rapeseed oil was added to equalise their energy content to Diets C and CE. Compared to Diets C and CE, the inclusion of the oat by-product in Diets O and OE increased the antioxidative capacity of water-soluble and lipid soluble compounds in these diets. Dietary treatment did not influence growth performance, slaughter value, longissimus dorsi (LD) muscle quality measured by nutrient contents, pH, drip loss or colour. Vitamin E supplementation increased the alpha-tocopherol concentration in serum and meat (p < 0.01), and decreased the formation of thiobarbituric acid reactive substances (TBARS) in the fresh and stored LD (p < 0.01). In addition, diets with the oat by-product increased serum alpha-tocopherol concentration (p < 0.01) and decreased the TBARS levels in the fresh and stored LD (p < 0.05), without increasing muscle alpha-tocopherol concentration. The obtained results indicate that the phenolic compounds present in oat by-products have a considerable antioxidant potential and a beneficial effect on the pig organism and oxidative stability of meat. However, dietary inclusion with the oat by-product was not as efficient as supplementation with vitamin E.     

Influence of dietary vitamin E and C supplementation on vitamin E and C content and thiobarbituric acid reactive substances (TBARS) in different tissues of growing pigs

To investigate the influence and possible interactions of dietary vitamin E and C supplementation on vitamin content of both vitamins and oxidative stability of different pork tissues 40 Large White barrows from 25?kg to 106?kg were allocated to four different cereal based diets: Basal diet (B), dl-α-tocopherylacetate?+?200?mg/kg (E), crystalline ascorbic acid?+?300?mg/kg (C) or both vitamins (EC). At slaughtering samples of liver, spleen, heart, kidney, backfat outer layer, ham and M. longissimus dorsi were obtained. Growth performance of the pigs and carcass characteristics were not influenced by feeding treatments. Dietary vitamin E supplementation had a significant effect on the vitamin E and α-tocopherol concentration in all investigated tissues. Backfat outer layer, liver, spleen, kidney and heart had higher vitamin E concentrations than ham and M. longissimus dorsi. Dietary vitamin C supplementation tended towards enhanced vitamin E levels except for ham samples. Therefore, some synergistic actions without dietary vitamin E supplementation between the two vitamins could be shown. The vitamin C concentration and TBARS were increased or at least equal in all tissues due to vitamin C supplementation. Dietary α-tocopherol supplementation resulted in lower TBARS in backfat outer layer (malondialdehyde 0.35?mg/kg in B vs. 0.28?mg/kg in E), but increased in heart and ham. When both vitamins were supplemented (EC) TBARS were lower in M. longissimus dorsi and backfat outer layer, equal in heart and higher in liver and ham compared to a single vitamin C supplementation. Rancimat induction time of backfat outer layer was 0.3?h higher in C compared to B and 0.17?h higher in EC than in E. Correlations between levels of both vitamins were positive for kidney (r?=?0.169), M. longissimus dorsi (r?=?0.499) and ham (r?=?0.361) and negative for heart (r?=???0.350). In liver and spleen no interaction could be found. In backfat outer layer vitamin E was positively correlated with rancimat induction time (r?=?0.550) and negatively with TBARS (r?=???0.202), but provided no evidence that dietary vitamin E supply led to better oxidative stability.