Deep-fried vegetable oils are reused multiple times to save costs, and their chronic consumption may cause organ dysfunction. In this study, we assessed the modulatory effects of lipid-solubles from ginger and turmeric that may migrate to oils during heating, on the cardio-hepatic antioxidant defence response and blood pressure in rats. Male Wistar rats were fed with: (1) control (native rapeseed (N-CNO) or native sunflower (N-SFO)) oil, (2) heated (heated rapeseed (H-CNO) or heated sunflower (H-SFO)) oil and (3) heated oil with ginger or turmeric (heated rapeseed oil with ginger (H-CNO + GI) or heated rapeseed oil with turmeric (H-CNO + TU), heated sunflower oil with ginger (H-SFO + GI) or heated sunflower oil with turmeric (H-SFO + TU)) for 120 d. Oxidative stress (OS) markers, antioxidant enzymes, nitric oxide synthase-2 (NOS-2), intercellular adhesion molecule-1 (ICAM-1), nuclear factor erythroid 2-related factor 2 (NRF-2), markers of hepatic and cardiac function and blood pressure were assessed. Feeding heated oils (H-CNO or H-SFO) (1) increased OS markers, NOS-2 and ICAM-1 expression; (2) decreased antioxidant enzyme activity and NRF-2 level; (3) increased marker enzymes of hepatic and cardiac function and (4) increased systolic and diastolic blood pressure significantly (P < 0·05), when compared with respective native oils (N-CNO or N-SFO). However, feeding oils heated with ginger or turmeric positively countered the changes induced by heated oils. Consumption of repeatedly heated oil causes cardio-hepatic dysfunction by inducing OS through NRF-2 down-regulation. Lipid-solubles from ginger and turmeric that may migrate to oil during heating prevent the oxidative stress and blood pressure triggered by heated oils in rats.

The infectivity and virulence of pathogenic trypanosomatids are directly associated with the efficacy of their antioxidant system. Among the molecules involved in the trypanosomatid response to reactive oxygen or nitrogen species, trypanothione reductase (TRed) is a key enzyme. In this study, we performed a molecular and functional characterization of the TRed enzyme from Trypanosoma rangeli (TrTRed), an avirulent trypanosome of mammals. The TrTRed gene has an open reading frame (ORF) of 1473 bp (~490 aa, 53 kDa) and occurs as a single-copy gene in the haploid genome. The predicted protein contains two oxidoreductase domains, which are equally expressed in the cytosol of epimastigotes and trypomastigotes. Nicotinamide adenine dinucleotide phosphate (NADPH) generation is reduced and endogenous H2O2 production is elevated in T. rangeli Choachí strain compared with T. cruzi Y strain epimastigotes. Oxidative stress induced by H2O2 does not induce significant alterations in TrTRed expression. Overexpression of TrTRed did not influence in vitro growth or differentiation into trypomastigotes, but mutant parasites showed increased resistance to H2O2-induced stress. Our results indicate that T. rangeli constitutively expresses TRed during the entire life cycle, with reduced levels during infective and non-replicative trypomastigote stages.

Dioxins are lipophilic compounds with a small molecular weight and are highly persistent, bioaccumulative and toxic. Dioxin detoxification is associated with an increased production of reactive oxygen species (ROS). In physiological conditions the body is protected against ROS and their toxic products by a wide range of antioxidant systems. We hypothesize that the imbalance between ROS production, associated with dioxin exposure, and the antioxidant defence capacity, may lead to oxidative stress, with consequent increased consumption of antioxidants and accumulation of toxic compounds in blood and tissues. The objective of this study was to evaluate the effect of exposure to dioxins on the plasma redox status of lactating buffalo cows. To this aim, the major liposoluble (retinol and α-tocopherol) and water-soluble (ascorbate) antioxidants, the superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity, the total antioxidant capacity (TAC), as well as specific protein oxidation markers (protein bound carbonyls and nitro-tyrosine) and lipid oxidation markers (hydroperoxides), were chosen as indices of blood redox status. The concentration of antioxidants, protein-bound carbonyls (PC), nitro-tyrosine (N-Tyr), and hydroperoxides (LPO), the SOD and GPx activity, and the TAC were measured in plasma samples obtained from buffalo cows exposed to environmental levels of dioxins higher (n=21, group A) or lower (n=29; group B) than those permitted. Plasma titres of antioxidants, as measured by HPLC, and the total antioxidant capacity, as measured by trolox equivalents capacity, were higher in group B than in A. Similarly, SOD and GPx activities were higher in group B than in A. Conversely, plasma levels of PC, N-Tyr and LPO, as measured by ELISA, were higher in group A than in B. Our results suggest that exposure to dioxins impairs the plasma antioxidant defence system of lactating buffalo cows, and that metabolic processes associated with dioxin detoxification might induce or enhance oxidation of protein and lipids. This adverse effect on blood redox status might have negative implications for animal health and reproduction, and might compromise animal welfare.

To evaluate the effect of antioxidant defence in coelomic fluid of sea cucumber, Apostichopus japonicus in aestivation was studied in the field from July to November 2006 in Qingdao. During the sampling period, activities of superoxide dismutase and catalase increased significantly in August and November. Activities of glutathione reductase and glutathione decreased significantly in August and increased significantly in November and activities of Se-glutathione peroxidase increased significantly in August. There were no significant differences in total glutathione peroxidase. In relation to the water temperature in the field, it is known that the oxygen consumption rate dropped and antioxidant defence was enhanced in August. The structure and function of respiratory trees of A. japonicus were completely vivified as normal in November, and it is suggested that antioxidant defence was enhanced because of the sharp change of oxygen consumption. Data indicate that both enzymatic and metabolite antioxidant defences in sea cucumber are adaptable systems that are modulated during pre-aestivating stage and arousing stage.

A diet rich in fruits, vegetables and minimally refined cereals is associated with lower risk for chronic degenerative diseases. Since oxidative stress is common in chronic degenerative disease, it has been assumed that dietary antioxidants may explain this protective effect. Every dietary plant contains numerous types of antioxidants with different properties. Many of these antioxidants cooperate in oxidative stress reduction in plants, and we hypothesize that many different antioxidants may also be needed for the proper protection of animal cells. To test this hypothesis, it is useful to identify dietary plants with high total antioxidant content. Several nuts are among the dietary plants with the highest content of total antioxidants. Of the tree nuts, walnuts, pecans and chestnuts have the highest contents of antioxidants. Walnuts contain more than 20 mmol antioxidants per 100 g, mostly in the walnut pellicles. Peanuts (a legume) also contribute significantly to dietary intake of antioxidants. These data are in accordance with our present extended analysis of an earlier report on nut intake and death attributed to various diseases in the Iowa Women's Health Study. We observed that the hazard ratio for total death rates showed a U-shaped association with nut/peanut butter consumption. Hazard ratio was 0·89 (CI =0·81–0·97) and 0·81 (CI =0·75–0·88) for nut/peanut butter intake once per week and 1–4 times per week, respectively. Death attributed to cardiovascular and coronary heart diseases showed strong and consistent reductions with increasing nut/peanut butter consumption. Further studies are needed to clarify whether antioxidants contribute to this apparent beneficial health effect of nuts.