Hypoxia and reoxygenation induced distinct patterns of response in antioxidant capacity between two cyprinid fish species.

Aim: To assess the role of antioxidants and lipid peroxidation in the pathogenesis of pre-eclampsia.
 Study Design: This is a case-control study designed to evaluate the levels of malondialdehyde and total antioxidant capacity with glutathione peroxidase and superoxide dismutase activities in pre-eclamptic. One hundred (100) participants were randomly selected to include fifty pre-eclamptic (test), twenty-five (25) healthy pregnant normotensive women (control A) and twenty-five healthy non-pregnant normotensive women (control B).
 Place and Duration of Study: This study was carried out at the Holy Rosary Hospital waterside, Onitsha, Anambra state. Nigeria. The study lasted for 13 months.
 Methodology: One hundred women (50 pre-eclamptic, 25 pregnant normotensives and 25 non-pregnant normotensives) aged 25-40 years were recruited for this study. Blood samples were collected from the participants for the estimation of total antioxidant capacity (TAC), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities using spectrophotometric methods. Blood pressures were measured using accosson sphygmomanometer. Data were analysed using analysis of variance and Pearson’s correlation coefficient at p < 0.05.
 Results: The TAC was significantly higher in the pregnant normotensives (p< 0.05) compared with the pre-eclamptic and non-pregnant normotensives. There was no significant difference in the MDA in pre-eclamptic compared with pregnant normotensives and non-pregnant normotensives (p>0.05). A significant difference was observed in the SOD and GPx activities in the pregnant normotensive and non-pregnant normotensives compared with pre-eclamptic. A positive correlation was observed between the blood pressures (systolic and diastolic) and the activities of TAC, SOD and GPx in pre-eclamptic. Furthermore, a positive correlation was observed between MDA levels and SBP (r = 0.019) while a negative correlation (r = -0.225) existed between MDA and DBP.
 Conclusion: Diminished ability of antioxidants to scavenge free radicals may affect the onset of pre-eclampsia and therefore possible prognostic tool in its management.

Purpose: Antioxidant enzymes such as glutathione peroxidase (GPx) and superoxide dismutase (SOD) constitute a defence against oxidative stress by scavenging key reactive oxygen species (ROS). In the context of acute coronary syndromes (ACS), the variance and prognostic significance of these enzymes is not clearly defined. Patients with low levels of GPx and SOD activity may have less capacity to scavenge ROS leading to an increased risk of Major Adverse Cardiovascular Events (MACE). This study aimed to test the hypothesis that patients with low levels of GPx and SOD activity would have a higher risk of MACE following an ACS. Methods: We prospectively enrolled ACS patients undergoing coronary angiography ± percutaneous coronary intervention. Clinical features and demographic data were recorded and blood samples collected prior to angiography. Plasma was assayed for GPx and SOD activity using colourimetric activity kits (Enzo LifeSciences). 1-year outcomes were collected, with a primary outcome measure of MACE, defined as a composite of death, myocardial infarction (MI), stroke (CVA), stent thrombosis and new heart failure (HF). Results: In 262 ACS patients (mean age 63 yrs, 69% male, 23% ST elevation MI, 71% non-ST elevation MI, 6% unstable angina) we observed considerable variation in the measures of GPx and SOD activity. The activity levels of these enzymes were not normally distributed. The median and inter-quartile range of GPx and SOD were 0.7 U/mg protein (0.5–0.9) and 0.2 U/mg protein (0.1–0.4) respectively. We observed a significant correlation between GPx and SOD activity (rho=0.3, \***|p<0.001). At 1-year 34 patients experienced MACE (10 deaths, 11 MI, 6 CVA, 5 stent thrombosis and 13 new HF). There was no significant correlation between either GPx activity and MACE (p=0.12) or SOD activity and MACE (p=0.36). Conclusion: In ACS patients we observed a large variance in both GPx and SOD activity. However, while some patients had low levels of antioxidant activity during the ACS presentation this was not associated with an increase in MACE at 1-year follow-up. A number of smaller studies report mixed results regarding the prognostic significance of these enzymes for cardiovascular events. To the best of our knowledge this is the largest study conducted in an acute population, and we did not identify a significant relationship between GPx or SOD activity and MACE. The cause and significance of low activity levels of these enzymes remain to be determined and is the focus of ongoing studies.

Effects of dietary β-glucan on growth rate, antioxidant status, immune response, and resistance against Aeromonas hydrophila in genetic improvement of farmed tilapia (GIFT, Oreochromis niloticus)

Oxidative stress, caused by excessive reactive oxygen species generation, impairs health and production performance of pigs. A number of nutrients and feed additives have antioxidative property. Our current research project is to study the antioxidative roles of methionine (a sulfur-containing amino acid) in pigs, and this abstract is to report our setup of an oxidative-stressed model by injection of diquat (dibromide monohydrate), a bipyridyl herbicide, to the pig. Barrows [n = 20, body weight (BW) = 21.5 ± 2.50 kg] were randomly allotted to two treatment groups fed a corn-and-soybean-meal-based diet that met or slightly exceeded the NRC (2012) recommended requirements of nutrients and energy. After 3 wk of feeding (Phase 1), while Group-1 pigs were intraperitoneally injected with 10 mL saline, Group-2 pigs were injected with 10 mg/kg BW diquat in 10 mL saline. After the injection, pigs were continually fed for 7 d more (Phase 2). At the end of Phases 1 and 2, average daily gain (ADG), average daily feed intake (ADFI), and gain to feed (G:F) ratios were respectively determined. Blood samples were collected on d 1, 22, and 29 of the experiment, and liver samples were collected on d 29. Commercial assay kits were used to determine the blood and liver redox status, for which the malondialdehyde (MDA) and glutathione (GSH) contents, the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities, and the total antioxidant capacity (TAC) were measured. The data was statistically analyzed using Student’s t-test. During Phase 1, there were no differences (P &amp;gt; 0.10) in initial BW, final BW, ADFI, ADG, and G:F ratio. There were no differences (P &amp;gt; 0.10) in the serum MDA contents, the serum GPX, SOD, and CAT activities, and the serum TAC and GSH contents between the two dietary treatment groups. By the end of Phase 2, however, the AFDI and ADG in Group 2 were less (P &amp;lt; 0.001) than that in Group 1. The serum MDA content in Group 2 was greater (P &amp;lt; 0.05) than in Group 1, the serum GPX activity and liver SOD activity in Group 2 was less (P &amp;lt; 0.05) than in Group 1, and the liver GPX activity in Group 2 tended to be greater (P = 0.10) than in Group 1, although there were no differences (P &amp;gt; 0.10) in serum SOD activity, serum TAC, and serum and liver CAT activities between the two treatment groups. In conclusion, the results of this study confirmed that young growing pigs intraperitoneally injected with diquat can lead to oxidative stress and serve as a model for studying antioxidant nutrients or feed additives in pigs.

This study was conducted to explore the regulation of N-acetyl cysteine (NAC) on gut redox status and proliferation of selected microbiota in weaned piglets. A total of 150 newborn piglets from 15 litters were randomly divided by litter to the control group (normally suckling), the weaning group (fed the basal diet), and the NAC group (basal + NAC diet) with 5 litters per group. Activities of total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and inhibition capacity of hydroxyl radical (IHR), and contents of malondialdehyde (MDA), H2O2, and NO in the ileum, colon, and cecum were analyzed to profile oxidative stress states. The real-time absolute quantitative PCR reaction was employed to quantify the amounts of total bacteria, Lactobacillus, Bifidobacterium, and Escherichia coli. The N-acetyl cysteine, as a universal antioxidant, was used to improve the redox status. Results showed that weaning stress resulted in the occurrence of gut oxidative stress and changes of gut microbiota (P < 0.05). Compared with the weaned piglets, the activities of ileal, colonic, and cecal T-AOC; ileal and colonic GSH-Px; cecal SOD; and colonic and cecal IHR were enhanced (P < 0.05), and the concentrations of ileal and cecal H2O2, ileal and colonic NO, and colonic MDA were reduced (P < 0.05) in the NAC-treated piglets. An increase (P < 0.05) in gut Lactobacillus and Bifidobacterium, accompanied with a decrease (P < 0.05) in Escherichia coli counts, was also observed in the NAC group. Bivariate correlation indicated that Lactobacillus and Bifidobacterium were positively correlated (P < 0.05) with the activities of T-AOC, GSH-Px, and SOD and inversely related (P < 0.05) to increased levels of H2O2, NO, OH, and MDA, and Escherichia coli showed a strong positive association (P < 0.05) with increased levels of free radicals and MDA and a negative association (P < 0.05) with the activities of antioxidant enzymes in intestines of weaned piglets. We concluded that NAC constructively regulated on the changes of the gut redox status and microbiota in piglets in response to weaning stress. The observed correlations implied that the NAC effects on the gut microbiota were confirmed, partly through an effect on oxidative stress in piglets, providing evidence that gut microbiota may be potentially improved by the modulation of the redox status by an antioxidant, which has relevance for gut health and function.

High-temperature environments significantly compromise the productivity of laying hens by damaging intestinal mucosal structure and impairing nutrient absorption. The effects of dietary canthaxanthin (CX) supplementation on egg production rate and intestinal health in Huaixiang chickens raised at high temperatures were assessed in this study. Six groups were randomly selected from among 216 hens: NC (basal diet, 25 ± 1°C), HC (basal diet, 32 ± 1°C for 8 h/day), and four HCX groups (basal diet supplemented with 4, 6, 8, or 10 mg/kg CX, 32 ± 1°C for 8 h/day), with six replicates of six birds each over 28 days. High temperature significantly decreased feed intake, egg production rate, and feed conversion ratio (FCR; p < 0.05), reduced serum total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities (p < 0.05), while increasing malondialdehyde (MDA) and reactive oxygen species (ROS; p < 0.05). High temperature also decreased T-AOC activity in the duodenum, jejunum and ileum (p < 0.05), and increased MDA and ROS levels in these intestinal segments (p < 0.05). Relative to the HC group, dietary CX increased egg production rate and FCR, enhanced serum T-AOC, SOD and GSH-Px activities, while reducing MDA and ROS levels (p < 0.05). CX increased T-AOC activity in the small intestine and decreased MDA and ROS levels (p < 0.05). In addition, heat stress impaired intestinal morphology, lowering villus height (VH), villus surface area (VSA), and villus height to crypt depth ratio (V/C; p < 0.05) while increasing apoptosis rate (p < 0.05). This was accompanied by decreased jejunal fatty acid binding protein 1 (FABP1) expression and lowered serum concentrations of total protein (TP), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C; p < 0.05). Relative to the HC group, dietary CX alleviated intestinal villus atrophy and rupture, effectively maintained normal small intestinal VH, VSA, and V/C ratios, and significantly reduced intestinal epithelial cell apoptosis rate. CX significantly increased serum TP, TG, TC, LDL-C, and HDL-C while maintaining normal expression levels of FABP1 mRNA in the jejunum. These results demonstrate that dietary supplementation with 8 mg/kg CX effectively mitigates high temperature-induced declines in egg production by improving intestinal nutrient absorption.

The purpose of this study was to investigate the exhaustive exercise-induced oxidative stress and the protective effect of oolong tea supplementation on malondialdehyde (MDA) levels, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in rat gastrocnemius muscle. Thirty-two male Sprague-Dawley rats were randomly divided into the following four groups: 1. control (C, n=8), 2. exhaustive exercise (CE, n=8), 3. oolong tea (O, n=8), 4. oolong tea-exhaustive exercise (OE, n=8). The amount of oolong tea extract supplementation was 0.5g/kg bodyweight per day for 4 weeks. The exhaustive exercise started at 10% grade, 15m min^(-1) for 10 min followed by gradual increases of treadmill speed and times until exhaustion. Two-way ANOVA was performed to examine the effects of exhaustive exercise and oolong tea supplementation on MDA, SOD, and GPx activities. The results showed that exercise-induced MDA levels were significantly higher than non-exercised rats (p＜.05), while MDA in OE group were significant lower than CE group (p＜.05). Muscle SOD activities in exercised rats were higher than non-exercised rats (p＜.05). Oolong tea supplemented rats also have higher SOD activities than non-oolong tea supplemented rats (p＜.05). Moreover, GPx activities in exhaustive exercised rats were significantly higher than non-exercised rats (p＜.05), while GPx activities in oolong tea supplemented rats were significantly higher than non-oolong tea supplemented rats (p＜.05). It is concluded that exhaustive exercise could result in oxidative stress. However, oolong tea supplementation is beneficial to decrease oxidative stress and increase the antioxidant status.

Aquaculture activity is affected by various environmental factors, including water salinity and high temperatures. The present study investigated the impact of using varying water salinity (0, 5, 10, 15 and 20 ppt) on the growth behavior, immune responses and antioxidative responses of common carp. Fish were raised under optimal conditions except for water salinity for 8 weeks; fish were then subjected to high-temperature stress (32 °C) for 48 h. The results indicated a reduced final weight (FBW), weight gain (WG), specific growth rate (SGR), condition factor (CF), feed intake and feed efficiency ratio (FER) in common carp reared in 15 and 20 ppt (p < 0.05). The lowest FBW, WG, SGR, CF, feed intake and FER values were observed in fish reared in 20 ppt water salinity (p < 0.05). In gills, the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were markedly decreased, but malondialdehyde (MDA) levels increased in fish challenged with 15 and 20 ppt before they were subjected to heat stress (p < 0.05). After heat stress, the SOD, CAT and GPx were decreased, and the MDA increased in fish reared in varying salinity levels (p < 0.05). Before heat stress, the intestinal SOD, CAT and GPx markers were decreased by 15 and 20 ppt, while the MDA level was increased by 15 and 20 ppt (p < 0.05). Generally, heat stress lowered the SOD, CAT and GPx activity in the intestines and liver tissues but increased MDA levels in common carp stressed by varying salinity levels (p < 0.05). The most decreased lysozyme activity, SOD, CAT and GPx and increased MDA levels were observed in common carp exposed to 20 ppt before and after heat stress (p < 0.05). After heat stress, fish exposed to 15 and 20 ppt had lower NBT than the remaining groups, and fish exposed to 20 ppt had the lowest values (p < 0.05). Overall, the heat stress markedly suppressed the antioxidant and immune responses of common carp reared in hypersalinity conditions.

Previous studies have shown sex-specific oxidative changes in spinal cord of rats submitted to chronic stress, which may be due to gonadal hormones. Here, we assessed total radical-trapping potential (TRAP), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and lipid peroxidation (evaluated by the TBARS test) in the spinal cord of ovariectomized (OVX) female rats. Female rats were subjected to OVX, and half of the animals received estradiol replacement. Animals were subdivided into controls and chronically stressed (for 40 days). Our findings demonstrate that chronic stress decreased TRAP, and increased SOD activity in spinal cord homogenates from ovariectomized female rats and had no effect on GPx activity. On the other hand, groups receiving 17β-estradiol replacement presented a decreased GPx activity, but no alteration in TRAP and in SOD activity. No differences in the TBARS test were found in any of the groups analyzed. In conclusion, our results support the idea that chronic stress induces an imbalance between SOD and GPx activities, additionally decreasing TRAP. Estradiol replacement did not reverse the effects of chronic stress, but induced a decrease in GPx activity. Therefore, estradiol replacement in ovariectomized chronically stressed rats could make the spinal cord more susceptible to oxidative injury.

Evaluation of softwood and hardwood sawmill wastes impact on the common carp "Cyprinus carpio" and its aquatic environment: An oxidative stress study

To investigate the effect of moxibustion at Shenque (CV 8) on free radical metabolism in rat’s hippocampus after different degrees of exhaustive exercise. A total of 72 male Sprague-Dawley (SD) rats were randomly divided into a normal group (n=8), a model group (n=32) and a moxibustion group (n=32). According to the times of modeling or treatment, the model group was further randomly divided into different subgroups of a 1-time model subgroup, a 4-time model subgroup, a 7-time model subgroup and a 10-time model subgroup (n=8); the moxibustion group was also further randomly divided into different subgroups of a 1-time moxibustion subgroup, a 4-time moxibustion subgroup, a 7-time moxibustion subgroup and a 10-time moxibustion subgroup (n=8). Rats in both model and moxibustion subgroups were subjected to establishing the swimming exhaustive model. Rats in each moxibustion subgroup received mild moxibustion at Shenque (CV 8) for 15 min immediately after modeling, once every other day. The concentration of malic dialdehyde (MDA), as well as the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) in rat’s hippocampus in each group were detected 24 h after the exhaustive exercise. Compared with the 1-time model subgroup, the exhaustive swimming time of rats was significantly prolonged in the 4-time model subgroup (P<0.01), while it was significantly shortened in the 7-time and 10-time model subgroups (both P<0.01). Compared with the matched model subgroup, the exhaustive swimming time of rats in the 7-time and 10-time moxibustion subgroups was significantly prolonged (both P<0.01). Compared with the normal group, the MDA concentration was increased significantly (P<0.01), and the activities stress response of SOD and T-AOC were increased in the 1-time model subgroup (both P<0.05); the MDA concentration was increased (all P<0.01), and the activities of SOD, GSH-Px and T-AOC were decreased differently (P<0.05 or P<0.01) in the 4-time, 7-time and 10-time model subgroups. Compared with the matched model subgroup, the concentration of MDA was significantly reduced (P<0.05 or P<0.01), and the activities of SOD, GSH-Px and T-AOC were significantly increased in the 4-time, 7-time and 10-time moxibustion subgroups (all P<0.01). Moxibustion at Shenque (CV 8) can improve the fatigue status of the body after long-term exhaustive exercise by regulating free radical metabolism in rat’s hippocampus. To some extent, this provides an experimental basis for moxibustion at Shenque (CV 8) against exercise-induced fatigue.

In this study, ameliorative effects of ellagic acid (EA) on oxidative stress induced by chlorpyrifos (CPF) in carp, Cyprinus carpio, were investigated. Fish were divided into six groups: C (no treatment), EA (100 mg kg fish−1), CPF-1 (0.040 mg L−1), CPF-2 (0.080 mg L−1), CPF-1 + EA, and CPF-2 + EA. CPF and EA were applied simultaneously for 14 days and, at the end of the study, liver, kidney, and gill samples were collected from fish. On the taken tissue samples, malondialdehyde (MDA) level and some antioxidant enzyme (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione-S-transferase (GST)) activities were evaluated. The results demonstrated statistically significant increases in the MDA levels of the CPF-1 and CPF-2 groups. On the other hand, the MDA levels were significantly decreased by EA administration. Also, CPF exposure caused statistically significant increases in the SOD and GST activities and statistically significant decreases in the CAT and GPx activities. However, treatment with EA reversed negative alterations in the SOD, CAT, GPx, and GST activities. Therefore, the results of this study results showed that simultaneous treatment with EA alleviates CPF-induced oxidative stress in fish.

Determination of superoxide dismutase and glutathione peroxidase activities in blood of healthy pediatric subjects

Oxidative stress, DNA damage and antioxidant enzyme activities in the pacific white shrimp (Litopenaeus vannamei) when exposed to hypoxia and reoxygenation

To investigate the relationship between clinical indicators of CRAB symptoms and antioxidant enzyme activity in patients with multiple myeloma (MM). The activity of catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD) in the bone marrow supernatants of 44 patients with MM and 12 patients with non-malignant hematological diseases was detected by colorimetric assay, and then the differences in the activity of antioxidant enzymes between the two groups were compared. Furthermore, the relationship between the activity of antioxidant enzymes in the MM group and the levels of serum calcium, serum creatinine (Scr), hemoglobin (Hb), alkaline phosphatase (ALP) as well as bone lesions were analyzed. The antioxidant enzyme activity was lower in MM patients compared with the control group (P < 0.05). When the concentrations of serum calcium and ALP were higher than the normal levels, Hb was lower than 85 g/L, and there were multiple bone lesions, the activity of CAT, SOD and GPX was significantly declined (P < 0.05); When the concentration of Scr≥177 μmol/L, the activity of GPX was significantly declined (P < 0.05). Regression analyses showed that CAT, SOD and GPX were negatively correlated with serum calcium (r =-0.538, r =-0.456, r =-0.431), Scr (r =-0.342, r =-0.384, r =-0.463), and ALP (r =-0.551, r =-0.572, r =-0.482). The activity of antioxidant enzymes, including CAT, SOD and GPX, were decreased in patients with MM and they were negatively correlated with some clinical indicators of CRAB symptoms (such as serum calcium, Scr, and ALP), which suggests that promoting the activity of antioxidant enzymes may be beneficial to treat the CRAB symptoms of the patients with MM.