Malonyldialdehyde Levels Research Articles

Elevated circulating free fatty acids levels causing pancreatic islet cell dysfunction through oxidative stress

Elevated plasma free fatty acids (FFA) concentration is predictive of the conversion from normal glucose tolerance and impaired glucose tolerance to diabetes. To evaluate the effects of prolonged exposure to FFA on basal and glucose-stimulated insulin secretion (GSIS) of pancreatic beta-cell, and to investigate the role of oxidative stress in FFA-induced decrease in beta-cell function. Rats were assigned to 3 groups and underwent 96-h infusions of normal saline (NS), intralipid plus heparin (IH), or intralipid plus heparin and N-acetylcysteine (IH+NAC). The plasma insulin, malonyldialdehyde (MDA), reduced glutathione (GSH), and oxidized glutathione (GSSG) were measured. In vivo intravenous glucose tolerance test (IVGTT) and ex vivo isolated pancreatic tissues perfusion were performed. In IH group GSIS both in IVGTT and perifused pancreatic tissues were impaired (p<0.05), the GSH/GSSG ratio was declined and MDA levels increased (p<0.05), the volume density score of nuclear factor kappaB and inducible nitric oxide synthase in pancreatic islets were increased compared to the NS group (p<0.01). In IH+NAC group, NAC intervention partly restored the GSH/GSSG ratio and MDA level, and improved FFA induced GSIS impairment. Elevated circulating FFA levels may contribute to causing the abnormalities of pancreatic islet cell function through active oxidative stress and oxidative stress-sensitive signaling pathway, which may play a key role in the development of impaired insulin secretion seen in obese Type 2 diabetes.

Improvement in oxidative stress and antioxidant parameters in β-thalassemia/Hb E patients treated with curcuminoids

Objectives To evaluate the hematological profile, oxidative stress, and antioxidant parameters in β-thalassemia/Hb E patients treated with curcuminoids for 12 months. Design and methods Twenty-one β-thalassemia/Hb E patients were given 2 capsules of 250 mg each of curcuminoids (a total of 500 mg) daily for 12 months. Blood was collected every 2 months during treatment and 3 months after withdrawal and was determined for complete blood count, malonyldialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) in red blood cells (RBC), and non-transferrin bound iron (NTBI) in serum. Results The increased oxidative stress in β-thalassemia/Hb E patients was shown by higher levels of MDA, SOD, GSH-Px in RBC, serum NTBI, and lower level of RBC GSH. Curcuminoids administration resulted in improvement of all the measured parameters as long as they were administered. After 3 months withdrawal of treatment, all parameters returned close to baseline levels. Conclusion Curcuminoids may be used to ameliorate oxidative damage in patients with β-thalassemia/Hb E disease.

Protective Effects from Carnosine and Histidine on Acetaminophen‐Induced Liver Injury

Protective effects of carnosine or histidine against acetaminophen-induced hepatotoxicity in Balb/cA mice were examined. Each compound, at 0.5, 1, or 2 g/L, was added into the drinking water for 4 wk. Acute liver injury was induced by acetaminophen treatment intraperitoneally (i.p. 350 mg/kg body weight). Acetaminophen treatment significantly depleted hepatic GSH and ascorbic acid levels, increased hepatic level of malonyldialdehyde (MDA), reactive oxygen species (ROS), and oxidized glutathione (GSSG), as well as decreased hepatic activity of glutathione peroxidase (GPX), catalase, and superoxide dismutase (SOD) (P < 0.05). However, the pre-intake of carnosine or histidine significantly alleviated acetaminophen-induced oxidative stress by increasing GSH content, decreasing MDA, ROS, and GSSG formations, and retaining activity of GPX, catalase, and SOD in liver (P < 0.05). The pre-intake of these compounds also significantly retarded subsequent acetaminophen-induced increase of cytochrome P450 2E1 activity (P < 0.05). Acetaminophen treatment increased the hepatic levels of interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-alpha, and monocyte chemoattractant protein (MCP)-1 (P < 0.05). The pre-intake of carnosine or histidine significantly diminished acetaminophen-induced elevation of these cytokines (P < 0.05). The impact of these compounds on mRNA expression of GPX, TNF-alpha, and MCP-1 indicated that these compounds could act at a transcription level. These results support that carnosine and histidine are potent hepatoprotective agents.

NMDA receptor blockage with 2-amino-5-phosphonovaleric acid improves oxidative stress after spinal cord trauma in rats

2-amino-5-phosphonovaleric acid (APV) is an N-methyl-D-aspartate (NMDA) receptor blocker and has neuroprotective properties. This study is aimed at evaluating the effect of APV treatment on oxidative status after spinal cord injury (SCI). The experiment was carried out on the following five groups: Group 1: sham operated, non-traumatized; Group 2: with injured spinal cord, no treatment; Group 3: with SCI, injected with 100 microg kg(-1) APV; Group 4: with SCI, injected with 200 microg kg(-1) APV; and Group 5: with SCI, injected with 400 microg kg(-1) APV. SCI was inflicted by epidural compression with a cerebral vascular clip after T9-11 laminectomy. The experiments were completed after 12 h of trauma. Spinal cords were excised for evaluation of superoxide dismutase (SOD), catalase, reduced glutathione (GSH) and malonyldialdehyde (MDA) levels. After SCI, SOD and GSH levels decreased and the MDA level increased significantly. APV treatment decreased the MDA level and increased SOD, catalase and GSH levels. The maximum decrease in MDA was detected in the group treated with 100 microg kg(-1) APV compared with the other groups. The GSH level was significantly increased in the group treated with 200 microg kg(-1) APV. The SOD level was significantly increased in the group treated with 200 microg kg(-1) APV. The results of this study have shown that APV treatment creates a dose-dependent antioxidant effect in rats with SCI and may be used for the treatment of SCIs.

Polyphenol metabolites from colonic microbiota exert anti‐inflammatory activity on different inflammation models

The polyphenols in fruits and vegetables may be partly responsible for the health-promoting effects attributed to fruit and vegetable intake. Although their properties have been relatively well studied, the activity of their metabolites, produced after ingestion, has been poorly investigated. Thus, the aim of this work was to study the potential anti-inflammatory effect of 18 polyphenol metabolites, derived from colon microbiota. They were screened by measuring prostaglandin E(2) (PGE(2)) production by CCD-18 colon fibroblast cells stimulated with IL-1beta. Metabolites that inhibited more than 50% PGE(2) production were hydrocaffeic (HCAF), dihydroxyphenyl acetic (dOHPA), and hydroferulic acid (HFER), that subsequently were tested with the writhing and paw pressure test in rodents where all three compounds showed an anti-inflammatory effect. The effect of HCAF administered orally (50 mg/kg) was also tested in the dextran sodium sulfate (DSS)-induced colitis model. Weight loss and fecal water content were more pronounced in DSS rats than in DSS-HCAF treated rats. HCAF treatment diminished the expression of the cytokines IL-1beta, IL-8, and TNF-alpha, reduced malonyldialdehyde (MDA) levels and oxidative DNA damage (measured as 8-oxo-2'-deoxyguanosine levels) in distal colon mucosa. These results indicate that HCAF, dOHPA, and HFER have anti-inflammatory activity in vitro and in vivo.

Drought Tolerance in Cotton: Involvement of Non‐enzymatic ROS‐Scavenging Compounds

AbstractCompounds with reactive oxygen species (ROS)‐scavenging ability were studied. High‐performance liquid chromatography (HPLC) pattern of polyphenols, contents of proline and carotenoids, and antiradical (AR) capacity were determined. The malonyldialdehyde (MDA) level was also assessed. Tolerant and sensitive cotton genotypes were compared, grown in the Aegean region of Turkey at normal (field capacity) and limited (1/3 field capacity) water supply. Chlorogenic acid isomers and flavonoids were identified in HPLC pattern of polyphenols. At normal water supply, the tolerant genotype was distinguished by a higher content of all polyphenol types, higher proline, carotenoids and AR capacity and lower MDA level compared with the sensitive genotype. In plants subjected to water deficit, a decline of all polyphenol compounds, carotenoids and AR capacity was observed. However, this response was less pronounced in the tolerant than in the sensitive genotype, i.e. despite the stress conditions imposed, the tolerant plants maintained a more effective defence system. The data are corroborated by the weaker structural membrane damage in the drought‐exposed tolerant vs. sensitive genotype, according to the MDA test. Hence, diverse chemical types are involved in the non‐enzymatic ROS‐scavenging system of cotton plants and can be related to the drought tolerance of this important crop.

Beneficial effects of L-arginine against diabetes-induced oxidative stress in gastrointestinal tissues in rats

Oxidative stress occurs in diabetic patients and experimental models of diabetes. The ability of L-arginine to ameliorate oxidative stress after treatment with alloxan was investigated in rats. Adult male rats were injected intraperitoneally with multiple doses of alloxan to produce experimental oxidative stress characteristic of diabetes mellitus. The rats were maintained in this state for eight weeks. Rats were decapitated and gastrointestinal tissues were isolated. The results were interpreted and the significance was analyzed using unpaired, two-tailed Student’s t tests and two-way repeated measures ANOVA. Hyperglycemia was observed in the plasma after three days of alloxan treatment. This was associated with a depression of glutathione (GSH) concentration as well as superoxide dismutase (SOD) and catalase (CAT) activities in the pylorus and ileum. In addition, the malonyldialdehyde (MDA) levels were significantly elevated, indicating increased lipid peroxidation and oxidative stress in the same tissues. L-arginine supplementation (0.15mg/ml) through drinking water until eight weeks after alloxan injection significantly ameliorated the oxidative stress, as evidenced by lower MDA levels as well as higher levels of endogenous GSH, SOD, and CAT (p<0.001). These effects were paralleled by marked protection and prophylaxis against alloxan-induced hyperglycemia. Thus, exogenously administered L-arginine might improve the clinical manifestation of diabetes mellitus and decrease the oxidative stress in the gastrointestinal tract. In addition, the study supports the beneficial effects of L-arginine. These effects might be attributed to its direct, NO-dependent antioxidant capacity and/or NO-independent pathways.

Oxidative stress but not endothelial dysfunction exists in non‐obese, young group of patients with polycystic ovary syndrome

To determine if oxidative stress and endothelial dysfunction exist at the same time in a young, non-obese group of patients with polycystic ovary syndrome (PCOS). Cross-sectional study. Celal Bayar University, School of Medicine, Manisa, Turkey. Thirty-one young, non-obese patients with PCOS and 23 age- and body mass index-matched controls. Following clinical and biochemical diagnosis, malonyldialdehyde (MDA), superoxide dismutase (SOD), von Willebrand Factor (vWF), and nitric oxide (NO) levels of patients and controls were measured and compared. To find out oxidative stress and endothelial dysfunction parameters. MDA (0.12+/-0.03 vs 0.10+/-0.03, p=0.01) and SOD (8.0+/-0.7 vs 7.28+/-0.8, p=0.001) levels were significantly higher in PCOS group while there was no difference in vWF (527.2+/-280.1 vs 568.1+/-276.8, p>0.05) and NO levels (169.9+/-47.4 vs 168.9+/-80, p>0.05). When the results of the PCOS patients were divided into two subgroups in terms of insulin resistance (IR- and IR + ), the IR- subgroup had significantly higher MDA levels compared to the control (0.125+/-0.03 vs 0.101+/-0.03, p=0.03). Though IR+ group also had higher MDA than the control group, it did not reach to a significant level (0.117+/-0.05 vs 0.101+/-0.03, p>0.05). Both IR- and IR+ groups had significantly higher SOD levels compared with control group (7.99+/-0.7 vs 7.28+/-0.8, p=0.009 and 8.22+/-0.8 vs 7.28+/-0.8, p=0.03, respectively). vWF and NO levels were not different among these three groups (p>0.05). Oxidative stress is prominent while endothelial dysfunction does not exist in young, non-obese patients with PCOS.

Protective effects of DIDS against ethanol-induced gastric mucosal injury in rats

The compound 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) is an efficient anion exchanger inhibitor that can block the activities of anion exchanger 2 (AE2), which plays an indispensable role in gastric acid secretion. DIDS also has potent anti-oxidative and antiapoptosis activities. This study aimed to investigate the effect of DIDS on ethanol-induced mucosal damage in rats and to evaluate the underlying mechanisms that mediate the action of the compound. The rats received 1 ml of absolute ethanol or saline orally. DIDS [50 mg/kg intravenous (i.v.)] was given 5 min before ethanol administration. Gastric lesions were evaluated macroscopically, microscopically, and electron microscopically at 60 min after ethanol challenge. Gastric myeloperoxidase (MPO) activity, malonyldialdehyde (MDA) level, prostaglandin E2 (PGE2) synthesis, and cyclooxygenase-2 (COX-2) expression were assessed. For the evaluation of the effect of DIDS on gastric acid secretion, histamine-stimulatory gastric acid secretion was examined with or without pretreatment of DIDS (50 mg/kg; i.v.). Ethanol-induced gastric lesions were characterized by increasing gastric MDA level, MPO activity, and COX-2 expression, and decreasing PGE2 synthesis. It was found that DIDS significantly reduced the extent of gastric mucosal damage and reversed tissue MDA level and MPO activity. DIDS further enhanced the expression of COX-2 and reversed the decrease of PGE2. Our results suggested that DIDS is beneficial in rat model of gastric injury through mechanisms that involve inhibiting inflammatory cell infiltration and lipid peroxidation and up-regulating the COX-2/PGE2 pathway.

Serum levels of malonyldialdehyde (MDA) and paraoxonase activities in patients with Behcet's disease

Objective The present study was undertaken to evaluate the levels of MDA as a marker of oxidative stress and activities of PON1 which may have a role as an antioxidant in Behcet's Disease (BD). Design & Methods In the present study, 16 patients of BD (7 male, 9 female, mean age: 31.26 ± 16.67) and 17 healthy individuals (7 male, 10 female, mean age: 32.7 ± 15.53) were included in the evaluation. Patients with BD were identified at the Dermatology Clinic of Dicle University Medicine Faculty Hospital. Diagnosis of BD was performed according to the criteria of the International Study Group on Behcet's Disease. Results In BD group, the medians of serum PON1 and MDA levels were 82.63 U/L and 2.25 nmol/ml, respectively. In the control group, median serum PON1 and MDA levels were 122.99 U/L and 1.43 nmol/ml, respectively. There was a statistically significant decrease in serum PON1 levels (82.63 ± 24.42 versus 122.99 ± 31.28; p p p > 0.05) and MDA levels (2.29 ± 0.71 versus 2.14 ± 0.24; p > 0.05) did not show any statistically significant difference. Conclusion Endothelial damage and increased polymorphonuclear leukocyte activity in the BD could result in decreased PON1 activity and increased MDA.

Determination of oxidative stress markers and their importance in early diagnosis of uremia-related complications

The existence of oxidative stress and the higher incidence of cardiovascular diseases in association with uremia is well proved. The uremic status of serum copper, ceruloplasmin (CP), protein thiols, malonyldialdehyde (MDA), and glutathione S-transferase (GST) levels was studied. The study was carried out on 51 chronic renal failure (CRF) patients who were not on hemodialysis therapy and on 42 healthy controls. Serum urea, creatinine, and MDA levels were found to be significantly increased (P < 0.001), and total protein, albumin, protein thiols, and copper levels were found to be significantly decreased in CRF patients compared to normal controls (P < 0.001). Ceruloplasmin levels were decreased significantly (P < 0.05), and there was no significant change in serum GST levels in CRF patients compared to normal controls. In conclusion, the significant increase in levels of MDA, and the decrease in levels of protein thiols, CP, and copper in uremia patients when compared to controls, reconfirms the presence of stress in this patient population. In view of the changes in other markers of oxidative stress, this absence of any significant change in the activity of GST in uremia patients compared to controls, warrants further study.

The effects of transient systemic hypotension on renal oxidative status, morphology and plasma nitric oxide levels in pregnant rats

Objective. Transient hypotension attacks, frequently experienced during pregnancy, have detrimental effects on maternal and fetal physiology. Despite the strong autoregulatory mechanisms, kidneys are remarkably sensitive to hypoperfusion. Transient hypotension together with high metabolic demand and increased oxygen requirement during pregnancy may disturb the oxidant status and natural course of nitric oxide (NO) metabolism. Therefore, we investigated in this study the effects of systemic hypotension during pregnancy on kidney oxidant status and morphology and plasma NO levels in an experimental hypotension model in rats.Methods. Twenty-four rats were allocated into four groups as non-pregnant control (NPC), non-pregnant hypotensive (NPH), pregnant control (PC) and pregnant-hypotensive (PH). Blood pressure was monitored only (NPC, PC) or systemic hypotension by blood withdrawal (NPH, PH) was produced for 30 min following catheterisation on the 15th day of pregnancy or at a corresponding time in the control animals. Animals were sacrificed after 48 h of reperfusion. Malonyldialdehyde (MDA) and reduced glutathione (GSH) levels, superoxide dismutase and catalase activities in the kidneys and plasma NO levels were measured. Tissues were evaluated, histologically.Results. Hypotension and/or pregnancy elevated MDA levels, which was significant in the NPH and PH groups (p < 0.05). GSH levels were lower in all groups compared with the NPC group (p < 0.05). Pregnancy itself increased NO only in the control animals (p < 0.05), not in the hypotensive pregnant rats. Transient hypotension resulted in kidney damage in both hypotension groups, and damage was more prominent in renal cortical regions. The most severe effects were seen in the PH group (p < 0.05).Conclusions. The findings of this study show that transient hypotension induces a kidney injury in pregnant rats. MDA and GSH in kidneys seem to play a role in the pathophysiology of this injury. However, the roles of antioxidant enzymes and NO and the other underlying mechanisms deserve and necessitate further investigation regarding the long-term health of the mother and fetus.

Interaction between endogenous cystathionine synthase/hydrogen sulfide and heme oxygenase-1/carbon monoxide systems during myocardial ischemic-reperfusion: experiment with rats

To investigate the interaction between the cystathionine synthase gene (CBS)/hydrogen sulfide (H(2)S) and heme oxygenase-1 (HO-1)/carbon oxide (CO) systems during myocardial ischemia-reperfusion. Twenty-four SD rats were randomly divided into 4 equal groups: ischemia-reperfusion (I/R) group undergoing intraperitoneal injection of normal saline (NS) and then 30 min later undergoing ligation of the left coronary artery (LCA) for 30 min, ischemia-reperfusion + zinc protoporphyrin (I/R + Z) group undergoing intraperitoneal injection of 45 micromol/kg zinc protoporphyrin, a HO-1 inhibitor, 30 min before the ligation of LCA, ischemia-reperfusion + hydroxylamine (I/R + H) group, undergoing intraperitoneal injection of 5 mmol/L hydroxylamine, a CBS inhibitor, 30 min before the ligation of LCA, and ischemia-reperfusion + zinc protoporphyrin + hydroxylamine (I/R + Z + H) group undergoing intraperitoneal injection of zinc protoporphyrin and hydroxylamine 30 min before the ligation of LCA. Another 6 rats underwent sham operation and intraperitoneal injection of NS 30 min before the operation and were used as control (C) group. The rats were killed 2 h after the reperfusion with their hearts taken out. Electron microscope was used to observe the mitochondrial structure. Homogenate of myocardium was prepared to examine the concentrations of H(2)S, CO, glutathione (GSH), malonyldialdehyde (MDA), activity of superoxide dismutase (SOD), and expression level of CBS-mRNA and HO-1-mRNA. The concentration of CO, H(2)S, GSH, and MDA increased, SOD activity decreased, and HO-1-mRNA and CBS-mRNA expression levels increased in Group I/R as compared with Group C (all P < 0.01). In Group I/R + Z the CO level decreased, H(2)S and GSH levels increased, and HO-1-mRNA expression level decreased, but CBS-mRNA expression level increased as compared with Group I/R (all P < 0.05). In Group I/R + H the H(2)S and GSH levels decreased, CO level increased, and HO-1-mRNA expression level increased and CBS-mRNA expression level decreased as compared with Group I/R (all P < 0.05). In Group I/R + Z + H the H(2)S, CO, GSH, and SOD levels decreased, MDA level increased, and HO-1-mRNA and CBS-mRNA expression levels decreased as compared with Group I/R (all P < 0.05). Electron microscopy found that mitochondrial structure was destroyed in the Groups I/R, I/R + Z, I/R + H, and most seriously in Group I/R + Z + H. Both CBS/H(2)S and HO-1/CO systems play a protective role in myocardial ischemia-reperfusion and they interact on each other.

Therapeutic effect and mechanism of proanthocyanidins from grape seeds in rats with TNBS-induced ulcerative colitis

The aim of the study was to investigate the therapeutic effect and mechanism of proanthocyanidins from grape seeds (GSPE) in the treatment of ulcerative colitis (UC). Rats were intragastrically administered different doses of GSPE (100, 200, and 400 mg/kg) per day for 7 days after UC was twice-induced by intracolonic injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS)dissolved in 50% ethanol. Sulfasalazine (SASP) at 200 mg/kg was used as a positive control drug. Macroscopic and microscopic damage scores and changes in weight/length ratio (mg/mm) of colon segments were analyzed. The levels of malonyldialdehyde (MDA), interleukin (IL)-1beta, IL-2, IL-4, and myeloperoxidase (MPO) activity in the colon tissues and MPO activity in the serum were all measured by biochemical methods or double antibody sandwich ELISA methods. Compared with the TNBS control group, GSPE treatment facilitated recovery of pathologic changes in the colon after insult with TNBS, as demonstrated by increased body weight (p < 0.01) and decreased colonic weight/length ratio (p < 0.01); GSPE also notably reduced the colonic macroscopic and microscopic damage scores (p < 0.01). The MPO activity in colon tissues and serum of rats treated with GSPE was significantly lower than that in the TNBS control group. The MDA and IL-1beta levels of colon tissues were also decreased in GSPE groups. The intestinal antiinflammatory effect of GSPE was accompanied by a significant improvement of IL-2 and IL-4 levels in the colon tissues of rats in the high-dose GSPE group (p < 0.05). Compared with the SASP group, GSPE groups had no significant difference in the therapeutic effect (p > 0.05). GSPE exerts a beneficial antiinflammatory effect in the acute phase of TNBS-induced colitis in rats by downregulating some of the mediators involved in the intestinal inflammatory response, inhibiting inflammatory cell infiltration and antioxidation damage, promoting damaged tissue repair to improve colonic oxidative stress, decreasing production of proinflammatory cytokines IL-1beta, and increasing production of antiinflammatory cytokines IL-2 and IL-4.

Advanced oxidation protein products are increased in women with polycystic ovary syndrome: relationship with traditional and nontraditional cardiovascular risk factors in patients with polycystic ovary syndrome

To determine whether or not plasma advanced oxidation protein products (AOPPs) are associated with known cardiovascular risk factors or carotid intima-media thickness (IMT) in patients with polycystic ovary syndrome (PCOS). A prospective, controlled study. University hospital. Forty-six women with PCOS and 46 age- and body mass index-matched healthy women. Carotid IMT was evaluated for both common carotid arteries. We measured serum levels of AOPP, homocysteine (Hcy), C-reactive protein (CRP), malonyldialdehyde (MDA), vitamin B(12), folate, lipid, and hormone profiles. The presence of insulin resistance was investigated by means of homeostasis model assessment (HOMA). Serum AOPP, fasting insulin, HOMA index, Hcy, MDA, CRP, and carotid IMT. The women with PCOS had significantly higher serum AOPP than control women. High AOPP was defined as equaling or exceeding the mean + 2 SD of the plasma AOPP in control subjects (56.2 pg/mLl). Carotid IMT, fasting insulin, HOMA index, Hcy, MDA, and CRP were significantly higher in PCOS patients with high AOPP than in those with normal AOPP. Fasting insulin, insulin resistance, and Hcy were independent determinants of plasma AOPP. Increased AOPP may contribute to the increased risk of atherosclerotic cardiovascular disease in women with PCOS.

Abnormal nuclear translocation of nuclear factor-E2 related factor 2 in the lesion of vitiligo

To investigate whether abnormal translocation of nuclear factor-E2 related factor 2 (Nrf2) exists in the lesion of vitiligo. Skin specimens from 8 vitiligo patients and 3 healthy controls were collected, half of them underwent laser co-focal microscopy to detect the Nrf2 location and half of them underwent cell culture. Blister fluid was collected form the 8 vitiligo patients and skin donor sites to detect the levels of serum superoxide dismutase (SOD), catalase (CAT), and malonyldialdehyde (MDA) by using detection kit. Expression of Nrf2 in epidermal cell of the 8 vitiligo patients and primary epidermal cell of the 3 healthy controls was identified with cell immunofluorescence histochemistry method. The nuclear and cytoplasmic proteins of all above samples were isolated to be identified by Western blotting. The levels of SOD and CAT in the lesion tissue were significantly lower than those in the skin donor site. The levels of MDA in the lesion tissue were significantly higher than those in the skin donor sites (both P < 0.05). Immunofluorescence histochemistry, showed that Nrf2 was predominantly cytoplasmic in the epidermal cells in the lesion, while Nrf2 expression could be seen in both the cytoplasm and nucleus in the epidermal cells in the normal skin donor sites and skins of the healthy controls. Western blotting showed that the nuclear Nrf2 level in the vitiligo skin lesion was (0.11 +/- 0.03), significantly lower than that in the normal skin donor site (0.27 +/- 0.06) and in the skins of the healthy controls (0.32 +/- 0.02) (both P < 0.01). However, there was no significant difference in the Nrf2 level of in cytoplasm among the three types of tissues (0.63 +/- 0.04, 0.61 +/- 0.03, and 0.65 +/- 0.04, all P > 0.05). Nrf2 does not translocate from cytoplasm into the nucleus in the lesion of vitiligo patients.

Ros Generation and Lipid Peroxidation in Professional Sportsmen (Extreme Sports Condition)

Introduction: Too intensive physical exercise may lower NO bioactivity as a result of excessive production of reactive oxygen species (ROS), such as superoxide anion radical (O 2 •– ). This can lead to the intense peroxidation of cell membrane lipids in erythrocytes. Aim of the study: The aim of the study was to evaluate the influence of dosed maximal exercise on the plasma nitric oxide content and the level of malonyl dialdehyde in red blood cells in professional sportsmen and in individuals of normal physical activity. Materials and Methods: 41 rugby players and 21 men of normal physical activity (control group) were the subject of the study. NO and MDA concentrations were determined in three time points: before an effort, 1 minute after dosed maximal exercise and after 30-minute restitution period. Nitric oxide (NO) concentration was evaluated with Griess’s indirect method and malonyl dialdehyde (MDA) concentration was measured with Placer’s method. Results: Mean NO concentration increased in the exercise phase and decreased after 30-minute restitution in all three studied groups. The highest MDA level was observed in the first minute of exercise in all studied groups. Conclusions: Results of determination of plasma NO concentration does not confirm reduction of its bioactivity. Plasma NO level rose 1 minute after maximal exercise in all three groups of studied subjects. In trained professional sportsmen, adapted to the physical effort, this kind of load enables protection of cell structures against peroxidation process by the antioxidant barrier, which is reflected by the lower concentration of malonyl dialdehyde (MDA) in the red blood cells in comparison to the control group.

Erythropoietin improves oxidative stress following spinal cord trauma in rats

Spinal cord injury (SCI) is a very destructive process for both patients and society. Lipid peroxidation is the main cause of the further secondary damage which starts after mechanical destruction of tissues. Recent studies have shown that erythropoietin (EPO) has neuroprotective properties. In this study, we aimed to see the effect of EPO treatment after spinal cord injury on the oxidant and anti-oxidant enzyme systems and the relationship with the N-methyl-D-Aspartate (NMDA) blockage. Spinal cord injury was produced by epidural compression with a cerebral vascular clip that has a closing force of 40 g for 30s after a limited multilevel laminectomy (T9-11). Experiment was done in 5 groups: Group 1: Sham-operated untraumatised, Group 2: SCI untreated, Group 3: 150 i.u./kg EPO injected i.p. at the end of the first hour following the trauma. Group 4: NMDA receptor antagonist ketamine (100mg/kg) i.p. Group 5: EPO+ketamine i.p. The experiments were finished after 12h of the trauma. The spinal cords were excised for biochemical examinations. Anti-oxidant enzymes; catalase and reduced glutathione (GSH) levels increased and lipid peroxidation product, malonyldialdehyde (MDA) level decreased in EPO treated group when compared to the other groups. TNF-alpha levels decreased in EPO treated group. Application of ketamine before EPO treatment decreased effects of EPO. In conclusion, our results suggest that 150 i.u./kg i.p. EPO, a therapeutic dose in anaemic patients, applied after 1h of spinal cord injury significantly attenuated the oxidative damage of spinal cord injuries in rats. This activity is abolished via ketamine pretreatment.

Effect of Green Tea on Iron Status and Oxidative Stress in Iron-Loaded Rats

Plasma non-transferrin bound iron (NTBI) is potentially toxic and contributes to the generation of reactive oxygen species (ROS), consequently leading to tissue damage and organ dysfunction. Iron chelators and antioxidants are used for treatment of thalassemia patients. Green tea (GT) contains catechins derivatives that have many biological activities. The purpose of this study was to investigate the iron-chelating and free-radical scavenging capacities of green tea extract in vivo. Rats were injected ip with ferric citrate together with orally administered GT extract (GTE) for 4 months. Blood was collected monthly for measurement of iron overload and oxidative stress indicators. Plasma iron (PI) and total iron-binding capacity (TIBC) were quantified using bathophenanthroline method. Plasma NTBI was assayed with NTA chelation/HPLC. Plasma malonyldialdehyde (MDA) was determined by using the TBARS method. Erythrocyte oxidative stress was assessed using flow cytometry. Levels of PI, TIBC, NTBI and MDA, and erythrocyte ROS increased in the iron-loaded rats. Intervention with GT extract markedly decreased the PI and TIBC concentrations. It also lowered the transferrin saturation and effectively inhibited formation of NTBI. It also decreased the levels of erythrocyte ROS in week 4, 12 and 16. Therefore, green tea extract can decrease iron in plasma as well as eliminate lipid peroxidation in plasma, and destroy formation of erythrocyte ROS in the rats challenged with iron. The bifunctional effects could be beneficial in alleviating the iron and oxidative stress toxicity. In prospective, these GTE activities should be further examined in thalassemic animals or humans.

Effects of Erdosteine on Acetaminophen-induced Hepatotoxicity in Rats

We investigated the effects of erdosteine on acetaminophen (APAP)-induced hepatotoxicity in rats. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), AST (aspartate aminotransferase), and ALT (alanine transaminase) activities, and malonyldialdehyde (MDA) and nitric oxide levels as oxidant/antioxidant biochemical parameters were investigated with light microscopic evaluation in adult female Wistar Albino rats. APAP administration produced a decrease in hepatic SOD, CAT, and GSH-Px activities, and coadministration of erdosteine (150 and 300 mg/kg) resulted in increases in the activities. MDA and NO levels increased in the APAP group, and erdosteine treatments prevented these increases. Significant elevations in serum AST and ALT levels were observed in the APAP group, and when erdosteine and APAP were coadministered, their serum levels were close to those in the control group. Light microscopic evaluation of livers showed that there were remarkable centrilobular (zone III) hepatic necrosis and mild to moderate sinusoidal congestion in the APAP group, whereas in the erdosteine group, cellular necrosis was minimal and the hepatocytes maintained a better morphology when compared to the APAP group. Erdosteine prevented APAP-induced liver injury and toxic side effects probably through the antioxidant and radical scavenging effects of erdosteine.