Effect of supplementation of two sources and two levels of copper on lipid metabolism in Nellore beef cattle

This study was conducted with 35 Nellore beef cattle to determine the effect of supplementation of two levels and two copper sources (organic and inorganic) on metabolism of lipids and cholesterol of meat. The five treatments used were: Control: without copper supplementation, 110 or 140: 10 or 40 mg/kg DM (as Cu sulfate), O10 or O40: 10 or 40 mg/kg DM (as Cu proteinate). In general, the copper supplementation changed the fatty acid profile of meat (p < 0.05), with a higher proportion of unsaturated fatty acids and reduction of saturated fatty acids. There was no effect of supplementation on blood cholesterol and triglycerides, however; in general, there was a reduction in cholesterol concentration in the L dorsi (p < 0.05) compared to the control treatment through the reduction (p < 0.05) in the concentrations of GSH and GSH/GSSG ratio. The Cu supplementation did have an influence on metabolism of lipids. The production of healthier meat is beneficial to public health by reducing the risk of cardiovascular disease. (C) 2012 Elsevier Ltd. All rights reserved.

Administration of a murine diet supplemented with conjugated linoleic acid increases the expression and activity of hepatic uncoupling proteins

Daily intake of conjugated linoleic acid (CLA) has been shown to reduce body fat accumulation and to increase body metabolism; this latter effect has been often associated with the up-regulation of uncoupling proteins (UCPs). Here we addressed the effects of a CLA-supplemented murine diet (similar to 2 % CLA mixture, cis-9, trans-10 and trans-10, cis-12 isomers; 45 % of each isomer on alternating days) on mitochondrial energetics, UCP2 expression/activity in the liver and other associated morphological and functional parameters, in C57BL/6 mice. Diet supplementation with CLA reduced both lipid accumulation in adipose tissues and triacylglycerol plasma levels, but did not augment hepatic lipid storage. Livers of mice fed a diet supplemented with CLA showed high UCP2 mRNA levels and the isolated hepatic mitochondria showed indications of UCP activity: in the presence of guanosine diphosphate, the higher stimulation of respiration promoted by linoleic acid in mitochondria from the CLA mice was almost completely reduced to the level of the stimulation from the control mice. Despite the increased generation of reactive oxygen species through oxi-reduction reactions involving NAD(+)/NADH in the Krebs cycle, no oxidative stress was observed in the liver. In addition, in the absence of free fatty acids, basal respiration rates and the phosphorylating efficiency of mitochondria were preserved. These results indicate a beneficial and secure dose of CLA for diet supplementation in mice, which induces UCP2 overexpression and UCP activity in mitochondria while preserving the lipid composition and redox state of the liver.

Fibers from fruit by-products enhance probiotic viability and fatty acid profile and increase CLA content in yoghurts

This study evaluated the effect of the supplementation of total dietary fiber from apple, banana or passion fruit processing by-products on the post-acidification, total titratable acidity, bacteria counts and fatty acid profiles in skim milk yoghurts co-fermented by four different probiotics strains: Lactobacillus acidophilus L10 and Bifidobacterium animalis subsp. lactis BL04, HN019 and B94. Apple and banana fibers increased the probiotic viability during shelf-life. All the fibers were able to increase the short chain and polyunsaturated fatty acid contents of yoghurts compared to their respective controls. A synergistic effect between the type of fiber and the probiotic strain on the conjugated linoleic acid content was observed, and the amount of alpha-linolenic acid was increased by banana fiber. The results of this study demonstrate, for the first time, that fruit fibers can improve the fatty acid profile of probiotic yoghurts and point out the suitability of using fibers from fruit processing the by-products to develop new high value-added fermented dairy products. (C) 2012 Elsevier By. All rights reserved.

Microbiota benefits after inulin and partially hydrolized guar gum supplementation - a randomized clinical trial in constipated women

Introduction: Prebiotics positively affect gut microbiota composition, thus improving gut function. These properties may be useful for the treatment of constipation. Objectives: This study assessed the tolerance and effectiveness of a prebiotic inulin/partially hydrolyzed guar gum mixture (I-PHGG) for the treatment of constipation in females, as well as its influence on the composition of intestinal microbiota and production of short chain fatty acids. Methods: Our study enrolled 60 constipated female health worker volunteers. Participants reported less than 3 bowel movements per week. Volunteers were randomized to treatment with prebiotic or placebo. Treatment consisted of 3 weeks supplementation with 15 g/d I-PHGG (fiber group) or maltodextrin (placebo group). Abdominal discomfort, flatulence, stool consistency, and bowel movements were evaluated by a recorded daily questionnaire and a weekly interview. Changes in fecal bacterial population and short chain fatty acids were assessed by real-time PCR and gas chromatography, respectively. Results: There was an increased frequency of weekly bowel movements and patient satisfaction in both the fiber and placebo groups with no significant differences. Total Clostridium sp significantly decreased in the fiber group (p = 0.046) and increased in the placebo group (p = 0.047). There were no changes in fecal short chain fatty acid profile. Conclusions: Consumption of I-PHGG produced clinical results comparable to placebo in constipated females, but had additional protective effects on gut rnicrobiota by decreasing the amount of pathological bacteria of the Clostridium genera.

Dose and latency effects of leucine supplementation in modulating glucose homeostasis: opposite effects in healthy and glucocorticoid-induced insulin-resistance states

Dexamethasone (DEXA) is a potent immunosupressant and anti-inflammatory agent whose main side effects are muscle atrophy and insulin resistance in skeletal muscles. In this context, leucine supplementation may represent a way to limit the DEXA side effects. In this study, we have investigated the effects of a low and a high dose of leucine supplementation (via a bolus) on glucose homeostasis, muscle mass and muscle strength in energy-restricted and DEXA-treated rats. Since the leucine response may also be linked to the administration of this amino acid, we performed a second set of experiments with leucine given in bolus (via gavage) versus leucine given via drinking water. Leucine supplementation was found to produce positive effects (e. g., reduced insulin levels) only when administrated in low dosage, both via the bolus or via drinking water. However, under DEXA treatment, leucine administration was found to significantly influence this response, since leucine supplementation via drinking water clearly induced a diabetic state, whereas the same effect was not observed when supplied via the gavage.

Probiotic yogurts manufactured with increased glucose oxidase levels: Postacidification, proteolytic patterns, survival of probiotic microorganisms, production of organic acid and aroma compounds

We investigated the effect of increased glucose oxidase concentration as a technological option to decrease oxidative stress during the processing of probiotic yogurts. Probiotic yogurts were produced with increased concentrations of glucose oxidase (0, 250, 500, 750, or 1,000 mg/kg) and submitted to physicochemical and microbiological analysis at 1, 15, and 30 d of refrigerated storage. Higher concentrations of glucose oxidase (750 and 1,000 mg/kg) and a longer storage time were found to have an influence on the characteristics of the probiotic yogurt, contributing to more extensive post-acidification, an increase in the dissolved oxygen level, and higher proteolysis. In addition, increased production of aroma compounds (diacetyl and acetaldehyde) and organic acids (mainly lactic acid) and a decrease in the probiotic bacteria count were reported. The use of glucose oxidase was a feasible option to minimize oxidative stress in probiotic yogurts. However, supplementation with excessive amounts of the enzyme may be ineffective, because insufficient substrate (glucose) is present for its action. Consumer tests should be performed to evaluate changes in the sensory attributes of the probiotic yogurts with increased supplementation of glucose oxidase. In addition, packaging systems with different permeability to oxygen should be evaluated.

Growth, carcass characteristics, chemical composition and fatty acid profile of the longissimus dorsi muscle in goat kids fed diets with castor oil

The objective in this study was to determine growth, carcass characteristics, chemical composition and fatty acid profile of the longissimus dorsi of crossbred Boer x Saanen kids fed castor oil. Twenty-four kids (12 males and 12 females) were assigned in a randomized complete block design with two treatments and twelve replications. Blocks were defined according to weight, gender and initial age of animals for the evaluation of performance. The experimental treatments consisted of two diets containing 900 g concentrate/kg: a control diet (without addition of oil) and another containing castor oil at 30 g/kg (on a dry matter basis). After they reached an average body weight of 25 kg, males were slaughtered for the evaluation of carcass characteristics, chemical composition and fatty acid profile of the longissimus dorsi muscle. The addition of castor oil in the diet did not affect the intake of dry matter, crude protein and neutral detergent fiber; the average daily gain; and feed conversion, but increased the ether extract intake. No difference was observed for the carcass characteristics, chemical composition of the meat, concentration of C18:2 cis-9, trans-11 (CLA) and total concentration of saturated, monounsaturated and polyunsaturated fatty acids and their relations; however, there was increase in the concentrations of C18:2 trans-10, cis-12 (CLA) and C20:4 omega-6. The addition of castor oil to the diet of crossbred Boer x Saanen kids containing a high content of concentrate did not promote benefit to the characteristics evaluated.

Supplementation of diets for Santa Ines sheep with organic and inorganic zinc sources

This research was conducted with objective to evaluate the effect of different zinc (Zn) sources and doses in the diet for Santa Ines sheep. Forty lambs at weaning, with 18.4 kg of body weight were supplemented with three different sources of zinc (zinc oxide (ZnO), zinc amino acid and zinc proteinate) and three doses of zinc (200, 400 and 600 mg/kg DM) added to the basal diet. At every 28 days, animals were weighted and blood samples were collected for analyses of zinc (Zn), alkaline phosphatase and immunoglobulin G (IgG) and M (IgM). At the end of experiment, liver samples were collected for determination of the hepatic zinc levels. Zinc was analyzed with atomic absorption spectrophotometer, while phosphatase alkaline and immunoglobulins G and M were analyzed using Laborlab and Bioclin kits, respectively. There was no effect of diets on phosphatase alkaline levels and hepatic zinc, but there was difference in the plasmatic zinc levels and IgG and IgM levels. Based on the accumulation of hepatic zinc, the estimate of the zinc bioavailability, through the regression equation, showed that supplementation with organic and inorganic sources of zinc did not differ in the diet of Santa Ines sheep.

Conjugated Linoleic Acid: good or bad nutrient

Conjugated linoleic acid (CLA) is a class of 28 positional and geometric isomers of linoleic acid octadecadienoic.Currently, it has been described many benefits related to the supplementation of CLA in animals and humans, as in the treatment of cancer, oxidative stress, in atherosclerosis, in bone formation and composition in obesity, in diabetes and the immune system. However, our results show that, CLA appears to be not a good supplement in patients with cachexia.

Effects of vitamin E supplementation on renal non-enzymatic antioxidants in young rats submitted to exhaustive exercise stress

Abstract Background Exercise stress was shown to increase oxidative stress in rats. It lacks reports of increased protection afforded by dietary antioxidant supplements against ROS production during exercise stress. We evaluated the effects of vitamin E supplementation on renal non-enzymatic antioxidants in young rats submitted to exhaustive exercise stress. Methods Wistar rats were divided into three groups: 1) control group; 2) exercise stress group and; 3) exercise stress + Vitamin E group. Rats from the group 3 were treated with gavage administration of 1 mL of Vitamin E (5 mg/kg) for seven consecutive days. Animals from groups 2 and 3 were submitted to a bout of swimming exhaustive exercise stress. Kidney samples were analyzed for Thiobarbituric Acid Reactive Substances to (TBARS) by malondialdehyde (MDA), reduced glutathione (GSH) and vitamin-E levels. Results The group treated with vitamin E and submitted to exercise stress presented the lowest levels of renal MDA (1: 0.16+0.02 mmmol/mgprot vs. 2: 0.34+0.07 mmmol/mgprot vs. 3: 0.1+0.01 mmmol/mgprot; p < 0.0001), the highest levels of renal GSH (1: 23+4 μmol/gprot vs. 2: 23+2 μmol/gprot vs. 3: 58+9 μmol/gprot; p < 0.0001) and the highest levels of renal vitamin E (1: 24+6 μM/gtissue vs. 2: 28+2 μM/gtissue vs. 3: 43+4 μM/gtissue; p < 0.001). Conclusion Vitamin E supplementation improved non-enzymatic antioxidant activity in young rats submitted to exhaustive exercise stress.

Effects of vitamin C supplementation on acute phase Chagas disease in experimentally infected mice with Trypanosoma cruzi QM1 strain

The tissue changes that occur in Chagas disease are related to the degree of oxidative stress and antioxidant capacity of affected tissue. Studies with vitamin C supplementation did not develop oxidative damage caused by Chagas disease in the host, but other studies cite the use of peroxiredoxins ascorbate - dependent on T. cruzi to offer protection against immune reaction. Based on these propositions, thirty "Swiss" mice were infected with T. cruzi QM1 strain and treated with two different vitamin C doses in order to study the parasitemia evolution, histopathological changes and lipid peroxidation biomarkers during the acute phase of Chagas disease. The results showed that the parasite clearance was greater in animals fed with vitamin C overdose. There were no significant differences regarding the biomarkers of lipid peroxidation and inflammatory process or the increase of myocardium in animals treated with the recommended dosage. The largest amount of parasite growth towards the end of the acute phase suggests the benefit of high doses of vitamin C for trypomastigotes. The supplementation doesn't influence the production of free radicals or the number of amastigote nests in the acute phase of Chagas disease.

Protein turnover, amino acid requirements and recommendations for athletes and active populations

Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers (13C-lysine, 15N-glycine, ²H5-phenylalanine) and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes) compared to resistance exercise, which induces fiber hypertrophy (myofibrils). Nitrogen balance (difference between protein intake and protein degradation) for athletes is usually balanced when the intake of protein reaches 1.2 g·kg-1·day-1 compared to 0.8 g·kg-1·day-1 in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins) and carbohydrate (± 30 g maltodextrine) drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h.

Modulation of plasma levels and percentages of incorporation of ω-3 PUFAs in egg yolk under the influence of supplementation sources rich in omega 3 to diet of laying

Hundred forty-four Shaver White laying hens were used over a 4 week experimental period to investigate the effect of 3% of soybean oil, corn oil (MIL), canola oil, flaxseed oil (LIN), salmon oil (SAL) or tuna and sardine oil (SR/AT) added to the diets, upon the fatty acid egg yolk composition, blood plasma levels and incorporation time of each fatty acid into the egg yolk. Hens were allocated into 72 cages and the experimental design was a 6 x 6 randomized factorial model. Hens fed 3% of different oils, responded with increased polyunsaturated fatty acids omega 3 (ω-3 PUFAs), except for corn oil. The addition of flaxseed, soybean or corn oil into the diet increased the PUFAs levels into the egg yolk and in the blood plasma. Adding tuna and sardine oil into the diet increased the concentration of yolk saturated fatty acids. The levels of ω-3 PUFAs were increased in the tuna and sardine oil treatment, while the flaxseed oil increased the plasma fatty acids. The deposition of 349.28 mg/yolk of a-linolenic fatty acids (ALA) was higher in the group fed LIN, while the higher equal to 157.13 mg DHA/yolk was observed in group SR/AT. In the plasma, deposition increased from 0.33% (MIL) for 6.29% ALA (LIN), while that of DHA increase of 0.47% (MIL) for 4.24% (SAL) and 4.48% (SR/AT) and of 0.98% (MIL) for 6.14% (SR/AT) and 8.44% (LIN) of ω-3 PUFAs. The percentage of EPA into the yolk and plasma was higher for the hens fed 3% tuna and sardine oil diet, as well as the levels of yolk DHA. The concentration of DHA into the plasma was higher for the salmon and tuna/sardine oil treatments. The PUFAs yolk decreased during the first eight days of experiment, while the ω-3 PUFAs increased during the same period. The concentration of ALA increased until ten days of experiment, while the percentage of EPA and DHA increased up to the eighth experimental day