Determination Of Antioxidant Status Research Articles

Effect of the Iberian pig rearing system on blood plasma antioxidant status and oxidative stress biomarkers

Forty-four pure Iberian pigs (14 months age, ~96.5 kg live weight) were randomly assigned to four different rearing systems: i. Free range conditions along with an acorn and pasture feed (AGFR), ii. Free range conditions with grass availability and fed on concentrate (CGFR), iii. Intensive system fed on concentrate supplemented with 100 ppm of α-tocopheryl acetate (α-TAc) (CI) and iv. Intensive system fed on concentrate supplemented with 200 ppm of α-TAc (CEI). Blood samples were taken every 30 days during 90 days (t0: 0d, t1: 30d, t2: 60d and t3: 90d -slaughter-) and tocopherols isomers contents, 2,2′-azino-bis (3-ethylbezothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) activities were measured in plasma as determinants of antioxidant status. At slaughter time (t3), TBA-RS and protein carbonyls were measured as biomarkers of lipid and protein oxidative damage. Acorn, grass and concentrate feeds were analysed and classified according to the content of tocopherols and antioxidant potential. 200 ppm of α-TAC supplementation increased α-tocopherol contents in feed. Acorns and pasture had high γ- and α-tocopherol contents, respectively, and both were found to show the highest antioxidant activities. Plasma from AGFR pigs contained significant (P < 0.05) higher amounts of α-tocopherol than those from CI and CGFR pigs and the highest amounts of γ-tocopherol (P < 0.05). At t1 and t2, DPPH and FRAP activities were significantly (P < 0.05) higher in AGFR plasma than in CI and CEI plasma. At slaughter time plasma from AGFR pigs had a higher resistance to oxidation with significant (P < 0.05) higher ABTS, DPPH and FRAP activities than plasmas from pigs kept in confinement and fed on concentrates. Lipid oxidation was significantly lower (P < 0.001) in plasma from AGFR pigs than in CI pigs while protein oxidation was not significantly affected (P > 0.05). Plasma from pigs fed on 200 ppm α-TAC enriched diets (CEI) or grass (CGFR) had intermediate antioxidant activities and TBA-RS. These results indicate that free range rearing system increased blood plasma antioxidant status while reduced lipid oxidative biomarker.

Thiol–Disulfide Homeostasis and Serum Ischemia Modified Albumin Levels in Patients with Primary Open–Angle Glaucoma

ABSTRACTAim: Glaucoma is an optic neuropathy causing progressive impairment of visual functions. We aimed to assess the alterations in thiol–disulfide homeostasis and serum ischemia modified albumin (IMA) levels, which are the determinants of antioxidant status, in patients with primary open-angle glaucoma (POAG).Material and Method: A total of 140 eyes from 70 patients with POAG and 174 eyes of 87 healthy, control cases were included in the study. All study participants underwent a complete ophthalmic evaluation. Alterations in serum thiol–disulfide homeostasis and IMA levels were measured in all participants.Results: IMA levels were significantly higher in glaucoma group (p:0.001). Native thiol, Total thiol and Native/Total thiol ratio were significantly decreased while Disulfide, Disulfide/Native thiol, and Disulfide/Total thiol ratios were significantly higher in glaucoma group (p:0.001). There was no significant difference regarding central corneal thickness (CCT), iridocorneal angle, albumin, IMA and adjusted IMA levels in patients with different stages of glaucoma. In correlation analysis, there was a negative correlation between Native thiol, Total thiol and Native/Total thiol ratio and disease period, number of daily drops required and stage of the disease in glaucoma patients. There was also a positive correlation between Disulfide, Disulfide/Native thiol and Disulfide/Total thiol levels and the disease activity.Conclusion: In patients with POAG, thiol–disulfide homeostasis is disturbed in the favor of pro-oxidant molecules and IMA levels are increased, indicating the presence of augmented oxidative stress. In that aspect, systemic and local anti-oxidant treatments may be new targets in glaucoma treatment. Larger, prospective studies about the role of anti-oxidants in prevention and treatment of POAG are warranted.

Influence of feeding thermally peroxidized soybean oil on oxidative status in growing pigs.

The objectives of this study were to determine whether feeding thermally processed peroxidized soybean oil (SO) induces markers of oxidative stress and alters antioxidant status in pig tissue, blood, and urine. Fifty-six barrows (25.3 ± 3.3 kg initial BW) were randomly assigned to dietary treatments containing 10% fresh SO (22.5 °C) or thermally processed SO (45 °C for 288 h, 90 °C for 72 h, or 180 °C for 6 h), each with constant air infusion rate of 15 liters/minute. Multiple indices of lipid peroxidation were measured in the SO including peroxide value (2.0, 96, 145, and 4.0 mEq/kg for 22.5, 45, 90, and 180 °C processed SO, respectively) and p-anisidine value (1.2, 8.4, 261, and 174 for 22.5, 45, 90, and 180 °C processed SO, respectively); along with a multitude of aldehydes. Pigs were individually housed and fed ad libitum for 49 d which included a 5 d period in metabolism crates for the collection of urine and serum for measures of oxidative stress. On day 49, pigs were euthanized to determine liver weight and analyze liver-based oxidative stress markers. Oxidative stress markers included serum, urinary, and liver thiobarbituric acid reactive substances (TBARS), and urinary F2-isoprostanes (ISP) as markers of lipid damage; serum and liver protein carbonyls (PC) as a marker of protein damage; and urinary and liver 8-hydroxy-2'-deoxyguanosine (8-OH-2dG) as a marker of DNA damage. Superoxide dismutase (SOD), and catalase activity (CAT) were measured in liver, glutathione peroxidase activity (GPx) was measured in serum and liver, and ferric reducing antioxidant power (FRAP) was measured in serum and urine as determinants of antioxidant status. Pigs fed 90 °C SO had greater urinary ISP (P = 0.02), while pigs fed the 45 °C SO had elevated urinary TBARS (P = 0.02) in comparison to other treatment groups. Pigs fed 45 °C and 90 °C SO had increased serum PC concentrations (P = 0.01) and pigs fed 90 °C SO had greater (P = 0.01) liver concentration of 8-OH-2dG compared to pigs fed the other SO treatments. Furthermore, pigs fed 90 °C SO had reduced serum GPx activity in comparison to pigs fed fresh SO (P = 0.01). In addition, pigs fed 180 °C SO had increased liver CAT activity (P = 0.01). Liver GPx and SOD or serum and urinary FRAP were not affected by dietary treatment. These results indicate that dietary peroxidized soybean oil induced oxidative stress by increasing serum PC while diminishing serum GPx, increasing urinary ISP and TBARS, and increasing 8-OH-2dG and CAT in liver.

Protective Effects of Mangiferin in Subchronic Developmental Lead-Exposed Rats

Lead is a ubiquitous environmental and industrial pollutant. Exposure to excessive amounts of lead is especially harmful to the central nervous systems of infants and young children, and oxidative stress has been reported as a major mechanism of lead-induced toxicity. To evaluate the ameliorative potential of antioxidant mangiferin (MGN) on lead-induced toxicity, Morris water maze test, determination of blood and bone lead concentration, determination of antioxidant status in plasma, as well as observation of ultrastructural changes in the hippocampus were carried out. In the present study, under a transmission electron microscope, ameliorated morphological damages in the hippocampus were observed in MGN-treated groups. Blood and bone lead concentration in MGN-treated groups lowered to some extent (p < 0.05, p < 0.01). The activities of antioxidant enzymes, glutathione (GSH) content, and the GSH/oxidized glutathione ratio in MGN-treated groups were increased, respectively. Further studies are needed to establish whether the observed differences were a direct cause of mangiferin on lead-induced toxicity or not. This study might provide clues for the treatment of lead-induced toxicity.

Determination of antioxidant status of pre-eclamptic and normotensive sub-rural Nigerian pregnant women at the Irrua specialist teaching hospital, Irrua, Edo State

Objectives: To determine the antioxidant levels of subrural Nigerian population where pre-eclampsia and eclampsia is the leading cause of maternal mortality. Methods: Prospective case control study done at Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital Irrua, Edo State, Nigeria. Plasma level of vitamin C and E were evaluated in 80 pre-eclamptic patientswhich were compared with normotensive 80 pregnant women matched as controls. Results: Pre-eclampsia was associated with significant reduction in levels of vitamin C and E (p < 0.05). However, the correlation between the blood pressure (severity) and reduction in antioxidants level was not statistically significant. Conclusion: Pre-eclampsia at Irrua in Nigeria is associated with significant reduction in plasma antioxidants level similar to some reports from the other parts of the world.