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Malondialdehyde Levels (malondialdehyde + level)
Selected AbstractsMelatonin ameliorates hippocampal nitric oxide production and large conductance calcium-activated potassium channel activity in chronic intermittent hypoxiaJOURNAL OF PINEAL RESEARCH, Issue 3 2008Y. W. Tjong Abstract:, Melatonin protects against hippocampal injury induced by intermittent hypoxia (IH). IH-induced oxidative stress is associated with decreases in constitutive production of nitric oxide (NO) and in the activity of large conductance calcium-activated potassium (BK) channels in hippocampal neurons. We tested the hypothesis that administration of melatonin alleviates the NO deficit and impaired BK channel activity in the hippocampus of IH rats. Sprague,Dawley rats were injected with melatonin (10 mg/kg, i.p.) or vehicle before daily IH exposure for 8 hr for 7 days. The NO and intracellular calcium ([Ca2+]i) levels in the CA1 region of hippocampal slices were measured by electrochemical microsenor and spectrofluorometry, respectively. The activity of BK channels was recorded by patch-clamping electrophysiology in dissociated CA1 neurons. Malondialdehyde levels were increased in the hippocampus of hypoxic rats and were lowered by the melatonin treatment. Levels of NO under resting and hypoxic conditions, and the protein expression of neuronal NO synthase (nNOS) were significantly reduced in the CA1 neurons of hypoxic animals compared with the normoxic controls. These deficits were mitigated in the melatonin-treated hypoxic rats with an improved [Ca2+]i response to acute hypoxia. The open probability of BK channels was decreased in the hypoxic rats and was partially restored in the melatonin-treated animals, without alterations in the expression of channel subunits and unitary conductance. Acute treatment of melatonin had no significant effects on the BK channel activity or on the [Ca2+]i response to hypoxia. Collectively, these results suggest that melatonin ameliorates the constitutive NO production and BK channel activity via an antioxidant mechanism against an IH-induced down-regulation of nNOS expression in hippocampal neurons. [source] Changes in malondialdehyde levels in bronchoalveolar fluid and serum by the treatment of asthma with inhaled steroid and beta2 -agonistRESPIROLOGY, Issue 3 2000Resat Ozaras Objective: Oxidative stress plays an important role in the pathogenesis of asthma. Recent data suggest that clinical indices of the patients with asthma may not correlate with the underlying inflammatory process. We aimed to measure the level of malondialdehyde (MDA), which is a marker of lipid peroxidation, a free radical-mediated process, before and after a well-accepted treatment of asthma. Methodology: Nine non-smoking females and five non-smoking males with mild,moderate asthma were included. Twenty-four age- and sex-matched, non-smoking healthy people (17 females and seven males, mean age 32.1 years, range 20,59) were included for control. After initial evaluation, spirometry, broncoscopy with bronchoalveolar lavage (BAL), and blood sample were maintained. The patients were treated with twice-daily salmeterol inhaler (100 ,g/d) and fluticasone propionate inhaler (500 ,g/d). One month later the investigations were repeated. Serum MDA levels before treatment were compared with both the levels after treatment and levels of controls. Malondialdehyde levels of BAL were compared before and after treatment. Results: Serum MDA level of the patient before treatment was 6.7 ± 0.8 nmol/mL, significantly higher than that of healthy controls; 3.8 ± 0.4, P < 0.001. One month after the treatment, serum MDA level decreased to 5.3 ± 0.7 nmol/mL (P < 0.001). However, this level is still significantly higher than healthy controls (P < 0.0001). Forced expiratory volume in 1 s level of the patients increased from 2.43 ± 0.79 L to 3.50 ± 1.21 L after the treatment (P < 0.001). Conclusion: Although treatment with beta2 -agonist and corticosteroid inhalers for the duration of 1 month reduced lipid peroxidation significantly, it was still at a level significantly higher than healthy controls. The treatment may need a longer duration to improve lipid peroxidation or an alternative regimen which is more effective in controlling inflammation may be warranted. [source] Possible involvement of GABAergic modulation in the protective effect of gabapentin against immobilization stress-induced behavior alterations and oxidative damage in miceFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 6 2007Anil Kumar Abstract Introduction Acute stress may be experienced in response to an immediate physical, emotional or psychological stimulus. Stress has been known to affect several brain activities and promote long-term changes in multiple neural systems. In the present study, we investigated the possible involvement of GABAergic modulation in the protective effect of gabapentin in acute immobilization-induced behavioral alterations and oxidative damage in mice. Materials and methods Mice were immobilized for periods of 6 h. Animals were divided into different groups, consisting of six in each. Various GABAergic modulators were administered either alone or in their combinations, 30 min before subjecting the animals for immobilization stress. Various behavioral tests (mirror chamber, actophotometer) followed by oxidative parameters (malondialdehyde level, glutathione, catalase, nitrite and protein) were assessed in animals. Results Six hours acute immobilization stress caused significant locomotor impairment, anxiety-like behavior in mice. Biochemical analyses also revealed an increase malondialdehyde, nitrite level and depletion of glutathione and catalase activity in 6 h stressed brains. Pretreatment with gabapentin (50 and 100 mg/kg, i.p.) significantly improved ambulatory movements, anti-anxiety effect (decreased time latency to enter in mirror chamber, increased number of entries and duration in mirror chamber) and antioxidative activity in stressed mice (P < 0.05). Further, picrotoxin (1.0 mg/kg) blocked and muscimol (0.05 mg/kg) potentiated the protective action of gabapentin (50 mg/kg). Results of both behavior as well as biochemical alterations in combination studies were significant as compared to their effect per se (P < 0.05). Conclusion Results of present study suggest GABAergic modulation might be involved in the protective effect of gabapentin against immobilization-induced behavior alteration and oxidative damage in mice. [source] Haemopexin affects iron distribution and ferritin expression in mouse brainJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 10 2009Noemi Morello Abstract Haemopexin (Hx) is an acute phase plasma glycoprotein, mainly produced by the liver and released into plasma where it binds heme with high affinity and delivers it to the liver. This system provides protection against free heme-mediated oxidative stress, limits access by pathogens to heme and contributes to iron homeostasis by recycling heme iron. Hx protein has been found in the sciatic nerve, skeletal muscle, retina, brain and cerebrospinal fluid (CSF). Recently, a comparative proteomic analysis has shown an increase of Hx in CSF from patients with Alzheimer's disease, thus suggesting its involvement in heme detoxification in brain. Here, we report that Hx is synthesised in brain by the ventricular ependymal cells. To verify whether Hx is involved in heme scavenging in brain, and consequently, in the control of iron level, iron deposits and ferritin expression were analysed in cerebral regions known for iron accumulation. We show a twofold increase in the number of iron-loaded oligodendrocytes in the basal ganglia and thalamus of Hx-null mice compared to wild-type controls. Interestingly, there was no increase in H- and L-ferritin expression in these regions. This condition is common to several human neurological disorders such as Alzheimer's disease and Parkinson's disease in which iron loading is not associated with an adequate increase in ferritin expression. However, a strong reduction in the number of ferritin-positive cells was observed in the cerebral cortex of Hx-null animals. Consistent with increased iron deposits and inadequate ferritin expression, malondialdehyde level and Cu,Zn superoxide dismutase-1 expression were higher in the brain of Hx-null mice than in that of wild-type controls. These data demonstrate that Hx plays an important role in controlling iron distribution within brain, thus suggesting its involvement in iron-related neurodegenerative diseases. [source] Neuroprotective effects of hydrogen sulfide on Parkinson's disease rat modelsAGING CELL, Issue 2 2010Li-Fang Hu Summary Parkinson's disease (PD) is a neurodegenerative disorder characterized by a progressive loss of dopaminergic neurons in the substantia nigra (SN). The present study was designed to examine the therapeutic effect of hydrogen sulfide (H2S, a novel biological gas) on PD. The endogenous H2S level was markedly reduced in the SN in a 6-hydroxydopamine (6-OHDA)-induced PD rat model. Systemic administration of NaHS (an H2S donor) dramatically reversed the progression of movement dysfunction, loss of tyrosine-hydroxylase positive neurons in the SN and the elevated malondialdehyde level in injured striatum in the 6-OHDA-induced PD model. H2S specifically inhibited 6-OHDA evoked NADPH oxidase activation and oxygen consumption. Similarly, administration of NaHS also prevented the development of PD induced by rotenone. NaHS treatment inhibited microglial activation in the SN and accumulation of pro-inflammatory factors (e.g. TNF-, and nitric oxide) in the striatum via NF-,B pathway. Moreover, significantly less neurotoxicity was found in neurons treated with the conditioned medium from microglia incubated with both NaHS and rotenone compared to that with rotenone only, suggesting that the therapeutic effect of NaHS was, at least partially, secondary to its suppression of microglial activation. In summary, we demonstrate for the first time that H2S may serve as a neuroprotectant to treat and prevent neurotoxin-induced neurodegeneration via multiple mechanisms including anti-oxidative stress, anti-inflammation and metabolic inhibition and therefore has potential therapeutic value for treatment of PD. [source] Effects of hyperbaric oxygen exposure on experimental hepatic ischemia reperfusion injury: Relationship between its timing and neutrophil sequestrationLIVER TRANSPLANTATION, Issue 12 2005Kenji Kihara Recent studies have shown that hyperbaric oxygen therapy (HBOT) reduces neutrophil endothelial adherence in venules and also blocks the progressive arteriolar vasoconstriction associated with ischemia-reperfusion (I-R) injury in the extremities and the brain. In order to elucidate the effects of HBOT after I-R in digestive organs, particularly in the liver, we evaluated the following: 1) the relationship between timing of HBOT and tissue damage; and 2) HBOT's effects on neutrophil sequestration. Using a hepatic I-R (45 minute) model in male rats, survival rate, liver tissue damage, and neutrophil accumulation within the sinusoids in the HBOT-treated group (Group H) were compared to those in the nontreated group (Group C). For the HBOT-treated group, HBOT was administered as 100% oxygen, at 2.5 atm absolute, for 60 minutes. When HBOT was given 30 minute after I-R, the survival rate was much better in Group H than in Group C. HBOT performed within 3 hours of I-R markedly suppressed increases in the malondialdehyde level in tissues of the liver and lessened the congestion in the sinusoids. In addition, HBOT just after I-R caused decreased number of cells stained by the naphthol AS-D chloroacetate esterase infiltrating into the sinusoids. HBOT 3 hours after reperfusion, however, showed no clear effects upon neutrophil sequestration compared to Group C. These results indicate that HBOT performed within 3 hours of I-R alleviates hepatic dysfunction and improves the survival rate after I-R. Herein, we propose 1 possible mechanism for these beneficial effects: early HBOT given before neutrophil-mediated injury phase may suppress the accumulation of neutrophils after I-R. In conclusion, we believe that the present study should lead to an improved understanding of HBOT's potential role in hepatic surgery. (Liver Transpl 2005;11:1574,1580.) [source] Identification of discriminant factors after treatment of resistant and susceptible banana leaves with Fusarium oxysporum f. sp. cubense culture filtratesPLANT BREEDING, Issue 1 2005B. Companioni Abstract Among the most important crops in developing countries are banana and plantain. However, the production is threatened by increasingly virulent forms of Fusarium wilt, and therefore, intensive breeding programmes are being carried out worldwide. As conventional field studies of banana resistance to this disease are time-consuming and destructive, an easy-to-do procedure was previously developed to differentiate field-grown resistant and susceptible banana cultivars at leaf level. Such a procedure involved the in vitro treatment of fungal culture filtrates on to field-grown adult leaves and the measurement of lesion areas 48 h later. The present report includes measurements of other indicators such as biochemical compounds. The cultivar ,Gross Michel' (susceptible) and cv. ,FHIA-01' (resistant) leaves were treated with Fusarium oxysporum f. sp. cubense race 1 culture filtrates. Evaluations were performed 48 h after leaf treatment. Compared with culture medium-treated leaves (control treatment), fungal metabolites produced leaf lesions, decreased freephenolic contents and increased protein levels in both cultivars. In ,FHIA-01', the culture filtrate increased contents of cell wall-linked phenolics and the pool of aldehydes (except malondialdehyde). Fungal metabolites did not cause variations in peroxidase activity, chlorophyll pigment contents or malondialdehyde level in any cultivar. The use of Fisher's linear discriminant analysis to differentiate resistant and susceptible banana cultivars in breeding programmes is also a novel aspect of this report. Such an estimation was performed from a data matrix that included the effects of the fungal metabolites (leaf lesion area and levels of free and cell wall-linked phenolics, aldehydes, except malondialdehyde, and proteins) on banana leaves of seven cultivars (four susceptible and three resistant). [source] Attenuation of Bleomycin-Induced Lung Fibrosis by Oxymatrine Is Associated with Regulation of Fibroblast Proliferation and Collagen Production in Primary CultureBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 3 2008Xiaohong Chen Oxymatrine is an alkaloid extracted from the Chinese herb Sophora japonica (Sophora flavescens Ait.) with capacities of anti-inflammation, inhibition of immune reaction, antivirus, protection against acute lung injury and antihepatic fibrosis. In this study, the effect of oxymatrine on pulmonary fibrosis was investigated using a bleomycin-induced pulmonary fibrosis mouse model. The results showed that bleomycin challenge provoked severe pulmonary fibrosis with marked increase in hydroxyproline content of lung tissue and lung fibrosis fraction, which was prevented by oxymatrine in a dose-dependent manner. In addition, bleomycin injection resulted in a marked increase of myeloperoxidase activity and malondialdehyde level that was attenuated by oxymatrine. Administration of oxymatrine inhibited the proliferation of murine lung fibroblasts, arrested the cells at G0/G1 phase and reduced the expression of cell cycle regulatory protein, cyclin D1 in vitro. Furthermore, the steady-state production of collagen and the expression of ,1(I) pro-collagen and ,2(I) pro-collagen mRNA in fibroblasts were inhibited by oxymatrine in a dose-dependent manner. These results suggested that oxymatrine may attenuate pulmonary fibrosis induced by bleomycin in mice, partly through inhibition of inflammatory response and lipid peroxidation in lung induced by bleomycin and reduction of fibroblast proliferation and collagen synthesis. [source] Protective Effect of Ebselen, a Selenoorganic Drug, against Gentamicin-Induced Renal Damage in RatsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 3 2006R. Dhanarajan However, its clinical use is limited by its nephrotoxicity. Oxidative stress and nitrosative stress are reported to play important role in gentamicin nephrotoxicity. In the present study we investigated whether ebselen, an inhibitor of oxidative stress and nitrosative stress prevents or reduces gentamicin-induced renal damage in the rat. For this purpose male Wistar rats were divided into five groups and treated as follows. Group 1 (control group): dimethyl sulphoxide, intraperitoneally, Group 2: Gentamicin 100 mg/kg b.wt. subcutaneously, Group 3: 5 mg/g b.wt. ebselen intraperitoneally, Group 4: 2.5 mg/kg b.wt. ebselen followed by 100 mg/kg b.wt. gentamicin subcutaneously one hour later, and Group 5: 5 mg/kg b.wt. of ebselen followed by 100 mg/kg b.wt. gentamicin one hour later for four consecutive days. Nephrotoxicity was evaluated histopathologically by light microscopy, and biochemically by the measurement of the plasma creatinine and urea levels. Parameters of oxidative stress such as reduced glutathione, malondialdehyde, and activities of superoxide dismutase and glutathione peroxidase were measured in the kidney. Serum nitrite and nitrate were measured as indicators of nitrosative stress. Treatment of rats with gentamicin resulted in statistically significant reduction in reduced glutathione levels (51%) and the activities of antioxidant enzymes superoxide dismutase (56%) and glutathione peroxidase (39%) as compared with the controls in the kidneys. Renal malondialdehyde level was increased significantly (43%) as compared with the controls. Plasma creatinine levels, urea levels and nitrite levels were significantly increased (4, 4.5 and 160% times respectively) as compared with the controls. Histologically, damage to the renal cortex and medulla was observed moderate to severe tubular necrosis and glomerular congestion. Pretreatment with 2.5 mg/kg b.wt. ebselen prevented gentamicin induced damage to medulla; however, renal cortex showed mild damage and biochemically indicators of oxidative stress and nitrosative stress were significantly reduced. Pretreatment with 5 mg/kg b.wt. ebselen prevented gentamicin-induced oxidative damage and nitrosative damage and renal damage almost completely in 78% of the rats, in the other 22% of the rats, ebselen pretreatment reduced gentamicin-induced renal damage. The results of the present study suggest that ebselen may be useful as a nephroprotective agent. [source] Effects of a selective Rho-kinase inhibitor Y-27632 on oxidative stress parameters in acute dichlorvos poisoning in ratsCELL BIOCHEMISTRY AND FUNCTION, Issue 7 2008N. Gunay Abstract This study examined the effects of Y-27632, a selective Rho-kinase inhibitor, on organophosphate-induced acute toxicity in rats. Rats were randomly divided into four groups as control (corn oil), dichlorvos (30,mg,kg,1 i.p.), 1 and 10,mg,kg,1 Y-27632,+,dichlorvos groups. Cholinergic signs (fatigue, tremor, cyanosis, hyper-secretion, fasciculations) were observed in all the rats in the dichlorvos group and the mortality rate was 50%. No cholinergic findings and deaths were observed in the control and Y-27632 groups. Plasma cholinesterase activities were suppressed with dichlorvos and these reductions were attenuated with Y-27632 pretreatment. There was a marked increase in plasma malondialdehyde level in the dichlorvos group, but Y-27632 pretreatment abolished this elevation. Dichlorvos markedly depressed cardiac paraoxonase activity, but these changes were not markedly modified with Y-27632. Total antioxidant capacities, total oxidant status, oxidative stress index, total free sulfhydryl groups and catalase activities in plasma and cardiac tissues were not markedly different between the groups. No significant changes were observed with cardiac myeloperoxidase activities or plasma arylesterase and ceruloplasmin activities. In conclusion, our results suggest that Rho-kinase pathway is involved in organophosphate intoxication, and a decrease in cardiac paraoxonase activities may play a role in the pathogenesis of acute organophosphate poisoning in rats. Copyright © 2008 John Wiley & Sons, Ltd. [source] Oxidative damage is increased in human liver tissue adjacent to hepatocellular carcinomaHEPATOLOGY, Issue 6 2004Christoph Jüngst Accumulation of genetic alterations in hepatocarcinogenesis is closely associated with chronic inflammatory liver disease. 8-oxo-2,-deoxyguanosine (8-oxo-dG), the major promutagenic DNA adduct caused by reactive oxygen species (ROS), leads to G:C , T:A transversions. These lesions can be enzymatically repaired mainly by human MutT homolog 1 (hMTH1), human 8-oxo-guanine DNA glycosylase (hOGG1) and human MutY homolog (hMYH). The aim of this study was to evaluate the extent of oxidative damage and its dependence on the cellular antioxidative capacity and the expression of specific DNA repair enzymes in tumor (tu) and corresponding adjacent nontumor (ntu) liver tissue of 23 patients with histologically confirmed hepatocellular carcinoma. 8-oxo-dG levels, as detected by high-pressure liquid chromatography with electrochemical detection, were significantly (P = .003) elevated in ntu tissue (median, 129 fmol/,g DNA) as compared to tu tissue (median, 52 fmol/,g DNA), and were closely associated with inflammatory infiltration. In ntu tissue, the hepatic iron concentration and malondialdehyde levels were significantly (P = .001) higher as compared to tu tissue. Glutathione content, glutathione peroxidase activity and manganese superoxide dismutase messenger RNA (mRNA) expression did not show statistical differences between ntu and tu tissue. Real-time reverse transcription polymerase chain reaction revealed in tu tissue significantly (P = .014) higher hMTH1 mRNA expression compared to ntu tissue. In contrast, hMYH mRNA expression was significantly (P < .05) higher in ntu tissue. No difference in hOGG1 mRNA expression was seen between tu and ntu. In conclusion, these data suggest that ROS generated by chronic inflammation contribute to human hepatocarcinogenesis. The role of DNA repair enzymes appears to be of reactive rather than causative manner. (HEPATOLOGY 2004;39:1663,1672.) [source] Iron chelation prevents lung injury after major hepatectomyHEPATOLOGY RESEARCH, Issue 8 2010Konstantinos Kalimeris Aim:, Oxidative stress has been implicated in lung injury following ischemia/reperfusion and resection of the liver. We tested whether alleviating oxidative stress with iron chelation could improve lung injury after extended hepatectomy. Methods:, Twelve adult female pigs subjected to liver ischemia for 150 min, 65,70% hepatectomy and reperfusion of the remnant liver for 24 h were randomized to a desferrioxamine (DF) group (n = 6) which received i.v. desferrioxamine to a total dose of 100 mg/kg during both ischemia and reperfusion, and a control (C) group (n = 6). We recorded hemodynamic and respiratory parameters, plasma interleukin-6 and malondialdehyde levels, as well as liver malondialdehyde and protein carbonyls content. Total non-heme iron was measured in lung and liver. Pulmonary tissue was evaluated histologically for its nitrotyrosine and protein carbonyls content and for superoxide dismutase (SOD) and platelet-activating factor acetylhydrolase (PAF-AcH) activities. Results:, Reperfusion of the remnant liver resulted in gradual deterioration of gas-exchange and pulmonary vascular abnormalities. Iron chelation significantly decreased the oxidative markers in plasma, liver and the lung and lowered activities of pulmonary SOD and PAF-AcH. The improved liver function was followed by improved arterial oxygenation and pulmonary vascular resistance. DF also improved alveolar collapse and inflammatory cell infiltration, while serum interleukin-6 increased. Conclusion:, In an experimental pig model that combines liver resection with prolonged ischemia, iron chelation during reperfusion of the remnant liver is associated with improvement of several parameters of oxidative stress, lung injury and arterial oxygenation. [source] Oxidative stress and hippocampus in a low-grade hepatic encephalopathy model: protective effects of curcuminHEPATOLOGY RESEARCH, Issue 11 2008Diego Martín Roselló Aim:, The present study was performed on prehepatic portal hypertensive rats, a model of low-grade hepatic encephalopathy, designed to evaluate whether oxidative stress was a possible pathway implicated in hippocampal damage and if so, the effect of an anti-oxidant to prevent it. Methods:, Prehepatic portal hypertension was induced by a regulated portal vein stricture. Oxidative stress was investigated by assessing related biochemical parameters in rat hippocampus. The effect of the anti-oxidant curcumin, administered in a single i.p. dose of 100 mg/kg on the seventh, ninth and eleventh days after surgery, was evaluated. Results:, Oxidative stress in the rat hippocampal area was documented. Curcumin significantly decreased tissue malondialdehyde levels and significantly increased glutathione peroxidase, catalase and superoxide dismutase activities in the hippocampal tissue of portal hypertensive rats. Conclusion:, Oxidative stress was found to be implicated in the hippocampal damage and curcumin protected against this oxidative stress in low-grade hepatic encephalopathic rats. These protective effects may be attributed to its anti-oxidant properties. [source] Occurrence of oxidative impairments, response of antioxidant defences and associated biochemical perturbations in male reproductive milieu in the Streptozotocin-diabetic ratINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 6 2007B. Shrilatha Summary Oxidative stress is implicated to play a vital role in the pathogenesis of various diabetic complications. While reproductive dysfunction is a well recognized consequence of diabetes mellitus, the underlying mechanisms are poorly understood. The present study aims to obtain insights into the incidence, extent and progression of oxidative impairments in testis and epididymal sperm (ES) in streptozotocin (STZ)-induced diabetic rat during early and progressive phase. Adult rats (CFT-Wistar strain) rendered diabetic by an acute dose of STZ (60 mg/kg bw, i.p.) were examined for induction of hyperglycaemia at 72 h, followed by the assessment of oxidative impairments in testis and ES over a 6-week period. Oxidative damage was ascertained by measuring the malondialdehyde levels, reactive oxygen species (ROS) generation, alterations in antioxidant defences and extent of protein oxidation. STZ induced a significant (2.5-fold) increase in blood glucose levels. In diabetic rats, both testis and ES showed enhanced status of lipid peroxidation measured as increased TBARS and ROS from week 2 onwards. These impairments in testis were consistent, progressive and accompanied by marked alterations in antioxidant defences and elevated protein carbonyls. Varying degree of reduction in the specific activities of antioxidant enzymes was evident in testis and ES, while the activity of glutathione- S -transferase (GST) was significantly elevated. Reduced glutathione (GSH) and vitamin E levels were consistently reduced in testis. Lipid dysmetabolism measured in terms of increased cholesterol, triglycerides and phospholipids was evident only beyond week 2 in diabetic testis. Taken together, these results indicate that the testis and ES are indeed subjected to significant oxidative stress in the STZ-diabetic rat both during early as well as progressive phase. It is hypothesized that oxidative impairments in testis which develop over time may at least in part contribute towards the development of testicular dysfunction eventually leading to testicular degeneration which culminates in reduced fertility during the progressive phase of STZ-induced diabetes in adult rats. [source] Haematological, hepatic and renal alterations after repeated oral or intraperitoneal administration of monoisoamyl DMSA.JOURNAL OF APPLIED TOXICOLOGY, Issue 6 2002Abstract Monoisoamyl 2,3-dimercaptosuccinic acid (MiADMSA), a vicinal thiol chelator, is gaining recognition recently as a better chelator than meso 2,3-dimercaptosuccinic acid (DMSA) in decreasing heavy metal burden in tissues because of its lipophilic character. There is, however, little information available on the toxicological properties of this chelator after repeated administration in animals. In the present study, we investigated the dose-dependent effect of MiADMSA on various biochemical parameters suggestive of alterations in haem biosynthesis and hepatic, renal and brain oxidative stress after 21 days of repeated intraperitoneal (i.p.) or oral (p.o.) administration to rats. The concentration of essential metals in blood and soft tissues was determined along with histopathological observations of hepatic and renal tissues. The results suggest that MiADMSA administration had no effect on blood ,-aminolevulinic acid dehydratase activity. However, an increase in zinc protoporphyrin and a decrease in haemoglobin levels were noted in animals given MiADMSA i.p. A moderate increase in serum alkaline phosphatase suggested mild hepatotoxicity at the highest dose (100 mg kg,1, i.p.). This was confirmed by histopathological examinations, which identified basophilic stippling, granulation of the cytoplasm, haemorrhage and congestion. At the highest dose, levels of hepatic thiobarbituric acid reactive substance and oxidized glutathione were increased above those of control values. Levels of hepatic reduced glutathione were decreased. Taken together, these observations point to oxidative stress. In animals administered MiADMSA i.p. there was an increase in the brain malondialdehyde levels at the two higher doses (50 and 100 mg kg,1). Essential metal status revealed a significant effect of MiADMSA (p.o.) in increasing blood zinc while significantly decreasing the kidney zinc level. The most significant adverse effect of MiADMSA was on copper concentration, which showed significant depletion from almost all major organs. Magnesium levels in blood decreased but increased in liver of MiADMSA-administered rats. Histopathological observations of liver and kidneys suggest few moderate lesions. It can be concluded that repeated administration of MiADMSA is compromised with some mild toxic effect, particularly the loss of copper. The effects during oral administration are comparatively less pronounced than by the i.p. route. Copyright © 2002 John Wiley & Sons, Ltd. [source] Methimazole protects lungs during hepatic ischemia,reperfusion injury in rats: An effect not induced by hypothyroidismJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 5 2007Tanju Tütüncü Abstract Background:, Hepatic ischemia,reperfusion injury may lead to remote organ failure with mortal respiratory dysfunction. The aim of the present study was to analyze the possible protective effects of methimazole on lungs after hepatic ischemia,reperfusion injury. Methods:, Forty male Wistar albino rats were randomized into five groups: a control group, in which bilateral pulmonary lobectomy was done; a hepatic ischemia,reperfusion group, in which bilateral pulmonary lobectomy was done after hepatic ischemia,reperfusion; a thyroidectomy,ischemia,reperfusion group (total thyroidectomy followed by, 7 days later, bilateral pulmonary lobectomy after hepatic ischemia,reperfusion); a methimazole,ischemia,reperfusion group (following methimazole administration for 7 days, bilateral pulmonary lobectomy was done after hepatic ischemia,reperfusion); and a methimazole +l -thyroxine,ischemia,reperfusion group (following methimazole and l -thyroxine administration for 7 days, bilateral pulmonary lobectomy was performed after hepatic ischemia,reperfusion). Pulmonary tissue specimens were evaluated histopathologically and for myeloperoxidase and malondialdehyde levels. Results:, All of the ischemia,reperfusion intervention groups had higher pulmonary injury scoring indices than the control group (P < 0.001). Pulmonary injury index of the ischemia,reperfusion group was higher than that of both the methimazole-supplemented hypothyroid and euthyroid groups (P = 0028; P = 0,038, respectively) and was similar to that of the thyroidectomized group. Pulmonary tissue myeloperoxidase and malondialdehyde levels in the ischemia,reperfusion group were similar with that in the thyroidectomized rats but were significantly higher than that in the control, and both the methimazole-supplemented hypothyroid and euthyroid groups. Conclusion:, Methimazole exerts a protective role on lungs during hepatic ischemia,reperfusion injury, which can be attributed to its anti-inflammatory and anti-oxidant effects rather than hypothyroidism alone. [source] Coagulation profile and platelet function in patients with extrahepatic portal vein obstruction and non-cirrhotic portal fibrosisJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2001Jasmohan S Bajaj Abstract Background and Aims: Coagulation disorders commonly develop in patients with cirrhosis of the liver. They have also been reported in patients with non-cirrhotic portal fibrosis (NCPF) and extra-hepatic portal venous obstruction (EHPVO); the two conditions with portal hypertension and near-normal liver functions. The spectrum and prevalence of coagulation abnormalities and their association with the pathogenesis of these diseases and with hypersplenism was prospectively studied. Methods: Eighteen EHPVO patients that included an equal number of NCPF patients and 20 healthy controls were prospectively studied. The coagulation parameters assessed included: international normalized ratio, partial thromboplastin time, and fibrinogen and fibrinogen degradation products. Platelet aggregation and malondialdehyde levels were measured. Results: Both EHPVO (83%) and NCPF (78%) patients had a significantly prolonged international normalized ratio and a decrease in fibrinogen and platelet aggregation. The EHPVO patients had a significant prolongation in partial thromboplastin time (67% patients), with increased levels of fibrinogen degradation product levels occurring in all patients; these were normal in NCPF patients. Platelet malondialdehyde levels were normal in both groups. Hypersplenism was present in four EHPVO and seven NCPF patients. It did not significantly influence the coagulation profile in either NCPF or EHPVO patients. Conclusions: Coagulation anomalies are common and significant in both NCPF and EHPVO patients, suggestive of a mild disseminated intravascular coagulation disorder. These imbalances could be caused by chronic subclinical endotoxemia and cytokine activation after the initial portal thromboembolic event. The persistence of these abnormalities in adolescent patients indicates an ongoing coagulation derangement. [source] Morphine or its withdrawal affects plasma malondialdehyde, vitamin E levels and absence or presence of abstinence signs in ratsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2009Professor Arnaldo Pinelli Abstract Objectives Various experimental observations show that morphine treatment generates reactive oxygen species, and that its discontinuation leads to signs of withdrawal. We therefore investigated plasma malondialdehyde and vitamin E levels under both conditions to verify the occurrence of any alterations in oxidative metabolism, and whether these are associated with behavioural changes. Methods We investigated the effects of morphine or morphine plus naloxone on plasma malondialdehyde, vitamin E levels and withdrawal signs such as jumping, wet dog shakes and faecal excretion in rats. Furthermore, isopropylnoradrenaline was injected in rabbits to verify its effects on plasma malondialdehyde levels. Key findings Morphine treatment increased free malondialdehyde and decreased vitamin E levels. The elevation in malondialdehyde levels were exacerbated by the abrupt removal of morphine by naloxone, which also led to the appearance of withdrawal signs. The increased malondialdehyde values can be attributed to the interactions of reactive oxygen species with unsaturated fatty acids, and the lowered levels of vitamin E to its interactions with reactive oxygen species. Conclusions A connection seems to exist between altered peroxide status and withdrawal signs in abstinent animals. [source] The Ethanol-soluble Part of a Hot-water Extract from Artemisia iwayomogi Inhibits Liver Fibrosis Induced by Carbon Tetrachloride in RatsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2000EUN-JEON PARK This study was carried out to investigate the protective effects of the hot-water extract from Artemisia iwayomogi (Compositae) on carbon tetrachloride-induced liver fibrosis in rats. Liver injury was induced by oral administration of carbon tetrachloride (1 mL kg,1) twice a week during 4 weeks of A. iwayomogi treatment. Extracts from A. iwayomogi were prepared and administered to rats orally (2 g kg,1 as A. iwayomogi for 4 weeks) as follows: group 1, hot-water extract; group 2, ethanol-soluble part of hot-water extract; group 3, ethanol-insoluble part of hot-water extract; and group 4, methanol extract. In rats treated with the ethanol-soluble part of the hot-water extract, liver hydroxyproline content was reduced to 74% that of carbon tetrachloride control rats (P < 0.05). Protein expression of alpha smooth muscle cell like actin was also decreased in rats treated with the ethanol-soluble part of the hot-water extract, which indicates inhibition of hepatic stellate cell activation. Liver malondialdehyde levels were significantly lowered in rats treated with the ethanol-soluble part of hot-water extract (P < 0.05). Serum cholesterol levels in rats treated with hot-water extract, ethanol-soluble or -insoluble parts of hot-water extract or methanol extract were significantly reduced when compared with those of carbon tetrachloride control rats (P < 0.05). The ethanol-soluble part of the hot-water extract from A. iwayomogi inhibited fibrosis and lipid peroxidation in rats with liver fibrosis induced by carbon tetrachloride. Both hot-water extract (either ethanol-soluble or -insoluble) and methanol extract of A. iwayomogi also lowered serum cholesterol levels in fibrotic rats. [source] Melatonin protects against pressure ulcer-induced oxidative injury of the skin and remote organs in ratsJOURNAL OF PINEAL RESEARCH, Issue 3 2006Göksel Abstract:, Pressure ulcers (PU) cause morphological and functional alterations in the skin and visceral organs; the damage is believed to be due to ischemia/reperfusion (I/R) injury. In this study, we examined the role of oxidative damage in PU and the beneficial effect of treatment with the antioxidant melatonin. PU were induced by applying magnets over steel plates that were implanted under the skin of rats; this compressed the skin and caused ischemia. Within a 12-hr period, rats were subjected to five cycles of I/R (2 and 0.5 hr respectively), followed by an additional 12 hr of ischemia (to simulate the period at sleep at night). This protocol was repeated for 3 days. In treatment groups, twice a day during reperfusion periods, melatonin (5 mg per rat) was either applied locally as an ointment on skin, or administered i.p. (10 mg/kg). At the end of the experimental period, blood and tissue (skin, liver, kidney, lung, stomach, and ileum) samples were taken for determination of biochemical parameters and for histological evaluation. Local treatment with melatonin inhibited the increase in malondialdehyde levels; an index of lipid peroxidation, myeloperoxidase activity; an indicator of tissue neutrophil infiltration, and the decrease in glutathione; a key antioxidant, in the skin induced by PU, but was less efficient in preventing the damage in visceral organs. However, systemic treatment prevented the damage in the visceral organs. Significant increases in creatinine, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and collagen levels in animals with PU were prevented by melatonin treatment. The light microscopic examination exhibited significant degenerative changes in dermis and epidermis in the PU rats. Tissue injury was decreased especially in the locally treated group. Findings of the present study suggest that local and/or systemic melatonin treatment may prove beneficial in the treatment of PU. [source] Short-Term Acetaldehyde Exposure Depresses Ventricular Myocyte Contraction: Role of Cytochrome P450 Oxidase, Xanthine Oxidase, and Lipid PeroxidationALCOHOLISM, Issue 4 2003Nicholas S. Aberle II Background: Chronic alcoholism leads to the development of alcoholic cardiomyopathy, manifested as ventricular dilation and impaired ventricular contractility. However, the specific toxic mechanism responsible for alcoholic cardiomyopathy remains unclear. One major candidate toxin is the first metabolic product of ethanol, acetaldehyde (ACA). This study was designed to examine the role of cytochrome P450 oxidase 2E1 (CYP 2E1), xanthine oxidase, and lipid peroxidation in the short-term ACA exposure-induced mechanical defects in adult rat ventricular myocytes. Methods: Mechanical and intracellular Ca2+ properties were evaluated by an IonOptix SoftEdge® system. Lipid peroxidation was assessed with malondialdehyde levels by using high-performance liquid chromatography. Results: Short-term (4- to 6-hr) culture of myocytes with ACA (1,100 ,M) in sealed containers with silicone septum depressed cell-shortening amplitude, maximal velocity of shortening/relengthening, and prolonged duration of relengthening, as well as intracellular Ca2+ clearing without any effect on the duration of shortening and electrically stimulated an intracellular Ca2+ increase. It is interesting to note that the ACA-induced effects on myocyte mechanical properties were abolished with co-treatment of the lipid peroxidation inhibitor butylated hydroxytoluene (20 ,M), the CYP 2E1 inhibitor diallyl sulfide (100 ,M), and the xanthine oxidase inhibitor allopurinol (100 ,M). Short-term incubation of ACA with the myocytes also produced a significant increase of the lipid peroxidation end product malondialdehyde, which may be prevented by butylated hydroxytoluene. Conclusions: Collectively, these data provided evidence that ACA depressed cardiomyocyte mechanical function at micromolar levels, possibly through mechanisms related to CYP oxidase, xanthine oxidase, and lipid peroxidation. [source] Prophylaxis with Centella asiatica confers protection to prepubertal mice against 3-nitropropionic-acid-induced oxidative stress in brainPHYTOTHERAPY RESEARCH, Issue 6 2010George K. Shinomol Abstract While the usage of Centella asiatica (CA) is on the increase worldwide, evidence demonstrating its protective efficacy against neurotoxicants is scarce. Hence the present study aimed to understand the neuroprotective efficacy of a standardized aqueous extract of CA against 3-nitropropionic-acid(3-NPA)-induced oxidative stress in the brain of prepubertal mice. We assessed the degree of oxidative stress in cytoplasm of brain regions of male mice (4,wk- old) given CA prophylaxis (5,mg/kg bw) for 10 days followed by 3-NPA administration (i.p.75,mg/kg bw) on the last 2 days. The neurotoxicant elicited marked oxidative stress in the brain of untreated mice as evident by enhanced malondialdehyde levels, reactive oxygen species (ROS) generation, hydroperoxides and protein carbonyls (a measure of protein oxidation) in striatum and other regions (cortex, cerebellum and hippocampus), while CA prophylaxis completely ameliorated the 3-NPA- induced oxidative stress. Depletion of glutathione (GSH) levels, total thiols, perturbations in antioxidant enzymes and cholinergic enzymes in brain discernible among 3-NPA-treated mice were predominantly restored to normalcy with CA prophylaxis. It is hypothesized that the prophylactic protection offered by CA extract against neurotoxicant exposure may be largely due to its ability to enhance GSH, thiols and antioxidant defenses in the brain of prepubertal mice. Copyright © 2009 John Wiley & Sons, Ltd. [source] Changes in malondialdehyde levels in bronchoalveolar fluid and serum by the treatment of asthma with inhaled steroid and beta2 -agonistRESPIROLOGY, Issue 3 2000Resat Ozaras Objective: Oxidative stress plays an important role in the pathogenesis of asthma. Recent data suggest that clinical indices of the patients with asthma may not correlate with the underlying inflammatory process. We aimed to measure the level of malondialdehyde (MDA), which is a marker of lipid peroxidation, a free radical-mediated process, before and after a well-accepted treatment of asthma. Methodology: Nine non-smoking females and five non-smoking males with mild,moderate asthma were included. Twenty-four age- and sex-matched, non-smoking healthy people (17 females and seven males, mean age 32.1 years, range 20,59) were included for control. After initial evaluation, spirometry, broncoscopy with bronchoalveolar lavage (BAL), and blood sample were maintained. The patients were treated with twice-daily salmeterol inhaler (100 ,g/d) and fluticasone propionate inhaler (500 ,g/d). One month later the investigations were repeated. Serum MDA levels before treatment were compared with both the levels after treatment and levels of controls. Malondialdehyde levels of BAL were compared before and after treatment. Results: Serum MDA level of the patient before treatment was 6.7 ± 0.8 nmol/mL, significantly higher than that of healthy controls; 3.8 ± 0.4, P < 0.001. One month after the treatment, serum MDA level decreased to 5.3 ± 0.7 nmol/mL (P < 0.001). However, this level is still significantly higher than healthy controls (P < 0.0001). Forced expiratory volume in 1 s level of the patients increased from 2.43 ± 0.79 L to 3.50 ± 1.21 L after the treatment (P < 0.001). Conclusion: Although treatment with beta2 -agonist and corticosteroid inhalers for the duration of 1 month reduced lipid peroxidation significantly, it was still at a level significantly higher than healthy controls. The treatment may need a longer duration to improve lipid peroxidation or an alternative regimen which is more effective in controlling inflammation may be warranted. [source] Effects of testosterone and vitamin E on the antioxidant system in rabbit testisANDROLOGIA, Issue 5 2004N. Aydilek Summary. The aim of the study was to investigate the effects of testosterone propionate and vitamin E on the antioxidant system in the testis. Thirty-two male New Zealand White rabbits were randomly divided into four groups. The first group was used as control. The second group was injected with testosterone propionate, the third group vitamin E and the fourth group vitamin E and testosterone propionate combination. All treatments were carried out during 6 weeks and oxidative parameters were evaluated in homogenized testicular tissue. The levels of vitamin E and the activity of glutathione peroxidase were lower (P < 0.05) in the testosterone group than in controls. However, vitamin C and malondialdehyde levels were higher (P < 0.05) in this group than in controls. The levels of reduced glutathione, , -carotene, vitamin C and E increased, but malondialdehyde levels decreased in the vitamin E group, when compared with controls (P < 0.05). Vitamin E and , -carotene levels were significantly higher (P < 0.05) in the combination group than in testosterone group. However, MDA levels were lower (P < 0.05) in combination group than in the testosterone group. In conclusion, administration of testosterone propionate led to a significant elevation of oxidative stress. Vitamin E is quite an effective antioxidant which protects rabbit testis against lipid peroxidation, and, testosterone-induced lipid peroxidation could be improved by additional vitamin E treatment. [source] 6-Gingerol prevents cisplatin-induced acute renal failure in ratsBIOFACTORS, Issue 3 2006Anurag Kuhad Abstract Background: Nephrotoxicity is a major complication and a dose limiting factor for cisplatin therapy. Recent evidence suggests that enhanced oxidative stress caused by oxygen-centered free radicals may contribute to the pathogenesis of cisplatin-induced acute renal failure. 6-Gingerol is claimed to be a potent antioxidant. The present study was performed to explore the renoprotective potential of 6-gingerol on cisplatin-induced oxidative stress and renal dysfunction. Methods: 6-Gingerol in dosages of 12.5, 25, 50 mg/kg was administered 2 days before and 3 days after cisplatin administration. Renal injury was assessed by measuring serum creatinine, blood urea nitrogen, creatinine, urea clearance and serum nitrite levels. Renal oxidative stress was assessed by determining renal malondialdehyde levels, reduced glutathione levels and enzymatic activities of superoxide dismutase and catalase. Results: A single dose of cisplatin resulted in marked renal oxidative and nitrosative stress and significantly deranged renal functions. 6-Gingerol treatment significantly and dose-dependently restored renal functions, reduced lipid peroxidation and enhanced the levels of reduced glutathione and activities of superoxide dismutase and catalase. Conclusions: The present study demonstrates the renoprotective potential of 6-gingerol against cisplatin-induced oxidative stress and renal dysfunction in rats. Hence, 6-gingerol has a potential to be used as therapeutic adjuvant in cisplatin nephrotoxicity. [source] Baicalin attenuates air embolism-induced acute lung injury in rat isolated lungsBRITISH JOURNAL OF PHARMACOLOGY, Issue 2 2009Min-Hui Li Background and purpose:, Baicalin has been reported to have anti-inflammatory effects and protect against various tissue injuries. However, the effect of baicalin on air embolism-induced acute lung injury has not been tested yet. Experimental approach:, Acute lung injury was induced by infusion of air at a rate of 0.25 mL·min,1 for 1 min into the pulmonary artery of rat isolated lungs. At the end of the experiment, samples were collected for assessment of lung injury, biochemical analysis and histology. Different doses of baicalin (1, 2 and 4 mg·kg,1) were given into the perfusate before air infusion. Key results:, Air embolism elicited a significant increase in microvascular permeability (Kf), lung weight gain, wet/dry weight ratio, pulmonary artery pressure and protein concentration in the bronchoalveolar lavage fluid. Levels of the cytokines, tumour necrosis factor , and cytokine-induced neutrophil chemoattractant-1 in perfusate, and malondialdehyde levels and myeloperoxidase activities in lung tissue were also significantly increased. In addition, histological examination showed increased neutrophil infiltration in lung tissues. Furthermore, nuclear factor-,B activity and degradation of I,B-, were significantly increased in lungs. Pretreatment of the lungs with baicalin (4 mg·kg,1) showed a statistically significant difference in all of the assessed parameters, except for alteration in the pulmonary artery pressure. Conclusions and implications:, Our study suggests that baicalin attenuated air embolism-induced acute lung injury and may be considered a useful adjunct drug therapy in this clinical condition. [source] Effects of caffeic acid phenethyl ester and alpha-tocopherol on reperfusion injury in rat brainCELL BIOCHEMISTRY AND FUNCTION, Issue 3 2003M. Kemal Irmak Abstract Oxygen-derived free radicals have been implicated in the pathogenesis of cerebral injury after ischaemia,reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. The purpose of the present study was to investigate the effects of ischaemia and subsequent reperfusion on rat brain and to investigate the effects of two free radical scavengers, CAPE and alpha-tocopherol, on this in vivo model of cerebral injury. Ischaemia was induced by bilateral occlusion of the carotid arteries for 20,min and reperfusion was achieved by releasing the occlusion to restore the circulation for 20,min. Control rats underwent a sham operation. CAPE at 10,,;mol,kg,1 or alpha-tocopherol at 25,,mol,kg,1 was administered intraperitoneally before reperfusion. Reperfusion led to significant increase in the activity of xanthine oxidase and higher malondialdehyde levels in the brain. Acute administration of both CAPE and alpha-tocopherol suppressed ischaemia,reperfusion-induced cerebral lipid peroxidation and injury, but CAPE seems to offer a better therapeutic advantage over alpha-tocopherol. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effects of electromagnetic radiation from a cellular telephone on the oxidant and antioxidant levels in rabbitsCELL BIOCHEMISTRY AND FUNCTION, Issue 4 2002M. Kemal Irmak Abstract The number of reports on the effects induced by electromagnetic radiation (EMR) in various cellular systems is still increasing. Until now no satisfactory mechanism has been proposed to explain the biological effects of this radiation. Oxygen free radicals may play a role in mechanisms of adverse effects of EMR. This study was undertaken to investigate the influence of electromagnetic radiation of a digital GSM mobile telephone (900,MHz) on oxidant and antioxidant levels in rabbits. Adenosine deaminase, xanthine oxidase, catalase, myeloperoxidase, superoxide dismutase (SOD) and glutathione peroxidase activities as well as nitric oxide (NO) and malondialdehyde levels were measured in sera and brains of EMR-exposed and sham-exposed rabbits. Serum SOD activity increased, and serum NO levels decreased in EMR-exposed animals compared to the sham group. Other parameters were not changed in either group. This finding may indicate the possible role of increased oxidative stress in the pathophysiology of adverse effect of EMR. Decreased NO levels may also suggest a probable role of NO in the adverse effect. Copyright © 2002 John Wiley & Sons, Ltd. [source] Caffeic acid phenetyl ester accelerates cutaneous wound healing in a rat model and decreases oxidative stressCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 6 2007G. Serarslan Summary Background., Cutaneous injury causes a depression in antioxidant status, as reactive oxygen species (ROS) are produced in response to injury., Aim., To determine the effects of caffeic acid phenethyl ester (CAPE), an antioxidant and anti-inflammatory agent, on wound healing in rats. Methods., In total, 40 male rats were divided into two groups: one group treated with CAPE (n = 20) and a second untreated control group (n = 20). A linear full-thickness incision was performed on the back of each rat and sutured. After incision, CAPE was given to the treatment group and saline to the control group. On days 1, 3, 7 and 14, five animals in each group were killed, and wound tissues dissected for biochemical and histopathological analysis. Results., Wound tissues showed a significant increase in glutathione and nitric oxide levels, and a significant decrease in malondialdehyde levels and superoxide dismutase levels in the CAPE group compared with the control group. Histopathology of the wound tissues displayed rapid epithelium development in the CAPE group compared with the control group. Conclusion., This study has demonstrated that CAPE partly accelerates full-thickness wound healing by its antioxidant and ROS-scavenging capabilities. [source] Differential regulation of nitric oxide synthase isoforms in experimental acute Chagasic cardiomyopathyCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 1 2000B. Chandrasekar We have previously demonstrated induction and high level expression of IL-1,, IL-6 and tumour necrosis factor-alpha in the myocardium during the acute stage of experimental Trypanosoma cruzi infection (Chagas' disease). The myocardial depressive effects of these cytokines are mediated in part by the induction of nitric oxide synthase (NOS), production of nitric oxide (NO) and formation of peroxynitrite. In this study we investigated the expression, activity and localization of NOS isoforms, and the levels of NO, malondialdehyde (a measure of oxidative stress), and peroxynitrite in rats at 1·5, 5, 10 and 15 days after infection with T. cruzi trypomastigotes. The myocardial inflammatory infiltrate and number of amastigote nests increased over the course of infection. A significant increase in tissue nitrate + nitrite levels, NOS2 mRNA, and NOS2 enzyme activity was observed at all time points in the infected compared with uninfected animals. The enzyme activity of constitutive NOS, tissue malondialdehyde levels, and NOS3 mRNA levels was only transiently increased after infection. The protein levels of the NOS isoforms paralleled their mRNA expression. While no positive nitrotyrosine immunoreactivity was detected in control myocardium, its levels increased in infected animals over time. Thus, by 1·5 days post-infection, when no parasite or immune cell infiltration could be detected, the myocardium expressed high levels of NOS and NO metabolites. Nevertheless, the early production of NO in the myocardium was not sufficient to clear the parasites. [source] |