Effects of vitamin C and E combination on element and oxidative stress levels in the blood of operative patients under desflurane anesthesia

Histopathological study on neuroapoptotic alterations induced by etomidate in rat hippocampus

In human, there is substantial neurogenesis in the hippocampus that is implicated in memory formation and learning. These new-born neurons can be affected by neuropathological conditions. Anesthesia and surgical procedures are associated with postoperative cognitive changes particularly, impaired memory and learning. Therefore, the aim of this study was to evaluate the possible neurodegenerative effects of etomidate in rat hippocampus. Thirty male Wistar rats weighing 250 ± 30 g were randomly divided into 3 groups: 1) Etomidate group; four times 20 mg intraperitoneal injection with 1-h intervals, 2) Control group; the equal volume of normal saline, and 3) Normal group; without any intervention. 6 h after the last injection, the brains were removed and processed according to routine histological methods. TUNEL assay and toluidine blue staining were performed to evaluate neuro-histopathological changes in different regions of hippocampus. Our results showed that the number of TUNEL positive cells and dark neurons (DNs) in etomidate group were significantly higher in the CA1, CA2, CA3, and dentate gyrus (DG) of hippocampus compared with the control and normal groups (p < 0.05). While, there was no significant difference between the various regions of hippocampus in control and normal groups. Our findings showed that etomidate can increase apoptotic cells and dark neurons induction in different regions of hippocampus mainly in DG.

Taurine Normalizes the Levels of Se, Cu, Fe in Mouse Liver and Kidney Exposed to Arsenic Subchronically

To evaluate the benefits of taurine on the homeostasis of trace elements induced by toxic metals, we investigated the concentration of Selenium (Se), Copper (Cu), Iron (Fe) and Manganese (Mn) in mouse liver and kidney after arsenic exposure for 2 months. The experimental animals were divided into control group, arsenic exposure group (1, 2, 4 ppm) and taurine protective group randomly. Concentrations of serum, liver and kidney trace elements such as Se, Cu, Fe, Mn were measured by Inductively Coupled Plasma-Mass Spectrometry. Our results showed that the concentration of Cu was higher, however, the concentration of Se and Fe was lower in mice liver and kidney exposed to arsenic. The levels of Se, Cu, Fe were alleviated by co-administered with taurine. Furthermore, there was no difference in the concentration of Mn between the three groups. Our finding suggests that taurine may relieve the disturbed levels of Se, Cu and Fe in liver and kidney induced by arsenic.

Effect of Zinc Supplementation on Antioxidant Defenses and Oxidative Stress Markers in Patients Undergoing Chemotherapy for Colorectal Cancer: a Placebo-Controlled, Prospective Randomized Trial

The study aimed to investigate the effect of oral zinc supplementation on antioxidant defenses and oxidative stress markers during chemotherapy for colorectal cancer. Twenty-four patients who had undergone surgical resection of colorectal cancer participated in this placebo-controlled, prospective randomized study. The supplementation was started in the perioperative period, in which 10 patients received 70 mg of zinc (zinc group, n = 10) and 14 patients received placebo (placebo group, n = 14) for 16 weeks. Approximately 45 days after surgical resection of tumor, all patients received a chemotherapeutic regimen (capecitabine, capecitabine combined with oxaliplatin or 5-fluorouracil). Vitamin C, vitamin E, antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), and lipid peroxidation markers malondialdehyde (MDA) and 8-isoprostane were determined before the first, second, third, and fourth chemotherapy cycles. Compared with the placebo group, the zinc group presented higher SOD values before the first, second, and fourth chemotherapy cycles and lower GPx values before the third cycle. There were no statistical differences between the study groups in vitamin C, vitamin E, MDA, or 8-isoprostane plasma values. Longitudinal analysis revealed decreased vitamin E concentration in the placebo group before the second and fourth cycles as compared with the initial values. Zinc supplementation during chemotherapy cycles increased SOD activity and maintained vitamin E concentrations. Although no effect of zinc supplementation on oxidative stress markers was observed, the increase in SOD activity indicates a production of stable free radicals, which may have a positive effect in cancer treatment.

[Effects of various anesthesia maintenance on serum levels of selenium, copper, zinc, iron and antioxidant capacity]

BACKGROUND AND OBJECTIVES

In this study, we aimed to investigate the effects of sevoflurane, desflurane and propofol maintenances on serum levels of selenium, copper, zinc, iron, malondialdehyde, and glutathion peroxidase measurements, and antioxidant capacity.

METHODS

60 patients scheduled for unilateral lower extremity surgery which would be performed with tourniquet under general anesthesia were divided into three groups. Blood samples were collected to determine the baseline serum levels of selenium, copper, zinc, iron, malondialdehyde and glutathion peroxidase. Anesthesia was induced using 2-2.5mgkg(-1) propofol, 1mgkg(-1) lidocaine and 0.6mgkg(-1) rocuronium. In the maintenance of anesthesia, under carrier gas of 50:50% O2:N2O 4Lmin(-1), 1 MAC sevoflorane was administered to Group S and 1 MAC desflurane to Group D; and under carrier gas of 50:50% O2:air 4Lmin(-1) 6mgkgh(-1) propofol and 1μgkgh(-1) fentanyl infusion were administered to Group P. At postoperative blood specimens were collected again.

RESULTS

It was observed that only in Group S and P, levels of MDA decreased at postoperative 48th hour; levels of glutathion peroxidase increased in comparison to the baseline values. Selenium levels decreased in Group S and Group P, zinc levels decreased in Group P, and iron levels decreased in all three groups, and copper levels did not change in any groups in the postoperative period.

CONCLUSION

According to the markers of malondialdehyde and glutathion peroxidase, it was concluded that maintenance of general anesthesia using propofol and sevoflurane activated the antioxidant system against oxidative stress and using desflurane had no effects on oxidative stress and antioxidant system.

Intracellular Ca2+ and antioxidant values induced positive effect on fertilisation ratio and oocyte quality of granulosa cells in patients undergoing in vitro fertilisation

Oxidative stress is important for promoting oocyte maturation and ovulation within the follicle through calcium ion (Ca(2+)) influx. The relationship between antioxidant and cytosolic Ca(2+) levels and oocyte quality and fertilisation rate in the granulosa cells of patients undergoing in vitro fertilisation was investigated. Granulosa cells were collected from 33 patients. Cytosolic free Ca(2+) ([Ca(2+)]i) concentration, lipid peroxidation, reduced glutathione, glutathione peroxidase and oocyte quality were measured in the granulosa cells. The relationship between two drug protocols was also examined (gonadotrophin-releasing hormone antagonist and agonist protocols) and the same parameters investigated. The [Ca(2+)]i concentration (P<0.001), glutathione (P<0.05) and oocyte quality (P<0.001) values were significantly higher in the fertilised group than in the non-fertilised group, although glutathione peroxidase activity was significantly (P<0.05) higher in the non-fertilised group than in the fertilised group. The [Ca(2+)]i concentrations were also higher (P<0.001) in the good-quality oocyte groups than in the poor-quality oocyte group. There was no correlation between the two drug protocols and investigated parameters. In conclusion, it was observed that high glutathione and cytosolic Ca(2+) concentrations in granulosa cells of patients undergoing in vitro fertilisation tended to increase the fertilisation potential of oocytes.

The effect of iron-vitamin C co-supplementation on biomarkers of oxidative stress in iron-deficient female youth

There is no study that assessed the effect of co-supplementation of iron and vitamin C on biomarkers of oxidative stress in non-anemic iron-deficient females. We investigated the effects of iron vs. iron + vitamin C co-supplementation on biomarkers of oxidative stress in iron-deficient girls. In a double-blind randomized controlled clinical trial, performed among 60 non-anemic iron-deficient girls, participants were randomly assigned to receive either 50 mg/day elemental iron supplements or 50 mg/day elemental iron + 500 mg/day ascorbic acid for 12 weeks. Fasting blood samples were taken at baseline, weeks 6 and 12 for assessment of biomarkers of oxidative stress. Compared with the baseline levels, both iron and iron + vitamin C supplementation resulted in a significant reduction in serum malondialdehyde (MDA) levels (P time < 0.001) and remarkable elevation in serum total antioxidant capacity (TAC; P time < 0.001) and vitamin C levels (P time = 0.001); however, comparing the two groups we failed to find an additional effect of iron + vitamin C supplementation to that of iron alone on serum TAC and MDA levels (P group was not statistically significant). Iron + vitamin C supplementation influenced serum vitamin C levels much more than that by iron alone (P group < 0.01). We also found a significant interaction term between time and group about serum vitamin C levels while this interaction was not significant about serum TAC and MDA levels. In conclusion, we found that iron supplementation with/without vitamin C improve biomarkers of oxidative stress among non-anemic iron-deficient females and may strengthen the antioxidant defense system by decreasing reactive oxygen species. Co-supplementation of iron + vitamin C has no further effect on oxidative stress compared with iron alone.

Proline alters antioxidant enzyme defenses and lipoperoxidation in the erythrocytes and plasma of rats: in vitro and in vivo studies

In the present study, we investigated, in vivo (acute and chronic) and in vitro, the effects of proline on the activities of antioxidant enzymes such as catalase (CAT), glutathione peroxidase and superoxide dismutase (SOD) in erythrocytes and also investigated the effect on thiobarbituric acid-reactive substances (TBARS) in the plasma of rats. For the experiments, the number of animals per group ranged from eight to ten. For acute administration, 29-day-old rats received one subcutaneous injection of proline (18.2 μmol/g body weight) or an equivalent volume of 0.9% saline solution (control) and were killed 1 h later. For chronic treatment, buffered proline was injected subcutaneously into rats twice a day at 10 h intervals from the 6th to the 28th day of age. Rats were killed 12 h after the last injection. For in vitro studies, proline (30.0 μM to 1.0 mM) was added to the incubation medium. Results showed that acute administration of proline reduced CAT and increased SOD activities, while chronic treatment increased the activities of CAT and SOD in erythrocytes and TBARS in the plasma of rats. Furthermore, in vitro studies showed that proline increased TBARS in the plasma (0.5 and 1.0 mM) and CAT activity (1.0 mM) in the erythrocytes of rats. The influence of the antioxidants (α-tocopherol plus ascorbic acid) on the effects elicited by proline was also studied. Treatment with antioxidants for 1 week or from the 6th to the 28th day of age prevented the alterations caused by acute and chronic, respectively, proline administration on the oxidative parameters evaluated. Data indicate that proline alters antioxidant defenses and induces lipid peroxidation in the blood of rats.

Isotretinoin treatment induces oxidative toxicity in blood of patients with acne vulgaris: a clinical pilot study

Acne vulgaris is the one of the most common skin diseases. Although isotretinoin (13-cis-retinoic acid) is an effective and well-tolerated medication, it has a wide range of side effects. Because the effects of isotretinoin on oxidant and antioxidant systems have not yet been clarified, we investigated plasma and erythrocyte antioxidant vitamins, lipid peroxidation (LP), reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values in patients with acne vulgaris before and after isotretinoin treatment. The study was performed on the blood plasma and erythrocytes of 31 acne vulgaris patients. Blood samples were taken from the patients before treatment and after isotretinoin (oral and 0·5-0·7 mg·kg(-1)) treatment for 2 months. Plasma amtioxidant vitamins, erythrocyte malondialdehyde, GSH and GSH-Px levels were measured. Plasma vitamin E (p < 0·001), lipid peroxidation (LP) and serum high-density lipoprotein cholesterol (p < 0·001) values were significantly lower in the treatment group than in the pre-treatment group, although erythrocyte LP (p < 0·001), GSH (p < 0·01) and GSH-Px (p < 0·001), aspartate aminotransferase (p < 0·05), alanine aminotransferase (p < 0·05), density lipoprotein cholesterol (p < 0·001) and total cholesterol (p < 0·01) levels were significantly higher in the treatment group than in the pre-treatment group. Vitamins A, C and β-carotene concentrations did not change significantly between the two groups. In conclusion, the results of the current study indicate that isotretinoin treatment induces oxidative stress and liver damage by decreasing plasma vitamin E and increasing erythrocytes GSH-Px, GSH and liver enzyme values.