首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Secondhand smoke (SHS) causes approximately 50,000 deaths per year. Despite all the health warnings, smoking is still allowed indoors in many states exposing both workers and patrons to SHS on a daily basis. The opponents of smoking bans suggest that present day air filtration systems remove the health hazards of exposure to SHS. In this study, using an acute SHS exposure model, we looked at the impact of commonly used air filters (MERV-8 pleated and MERV-8 pleated activated charcoal) on SHS by assessing the inflammatory response and the oxidative stress response in C57BL/6 mice. In order to assess the inflammatory response, we looked at the tumor necrosis factor alpha (TNF-α) cytokine production by alveolar macrophages (AMs), and for the oxidative response, we quantified the products of lipid peroxidation and the total glutathione (tGSH) production in lung homogenates. Our results showed that SHS caused significant immune and oxidative stress responses. The tested filters resulted in only a modest alleviation of inflammatory and oxidative responses due to SHS exposure. Our data show that these air filters cannot eliminate the risk of SHS exposure and that a short-term exposure to SHS is sufficient to alter the inflammatory cytokine response and to initiate a complex oxidative stress response. Our results are consistent with the statement made by the Surgeon General’s reports that there is no risk free level of exposure to SHS.  相似文献   

2.
1. The effect of calcium paradox on oxidative status and the activity of anti-oxidant enzymes were studied in the rat isolated heart. Glutathione status, sulphydryl group contents and lipid peroxidation in the myocardium, as well as the release of oxidized and reduced glutathione from the heart, were taken as indices of oxidative events. 2. Reperfusion with calcium after calcium-free perfusion induced a significant decrease in the myocardial content of reduced and oxidized glutathione and non-protein sulphydryl groups. At the same time, a significant release of both forms of glutathione from the heart was observed. However, the ratio of oxidized to reduced glutathione remained unchanged and was not different from control. Increased lipid peroxidation was observed only after 30 min of reperfusion with calcium. 3. Increased anti-oxidant activity during the reperfusion period was observed. Mitochondrial Mn-superoxide dismutase (SOD) activity was increased throughout the reperfusion period, while cytoplasmic Cu,Zn-SOD and glutathione peroxidase activity showed a transient increase at 5 min reperfusion. 4. The results do not support an important role of oxygen free radicals in cell damage observed during calcium paradox in the rat isolated heart. Production of oxygen free radicals may occur during the reperfusion period, but the quantity produced is insufficient to exceed the anti-oxidant capacity of the heart.  相似文献   

3.
BackgroundTobacco smoking and alcohol abuse causes oxidative stress in humans and underlay numerous chronic degenerative diseases. Liver is the main organ exposed to alcohol toxic metabolites, whereas tobacco smoke is chiefly harmful to the lungs.MethodsThe aim of the current study was the assessment and comparison of selected oxidative stress markers, reduced glutatione (GSH), glutathione S-transferase (GST), superoxide dismutase (SOD), catalase, nitrites and protein nitrosylation and DNA damage in the livers and in the lungs of alcohol-addicted rats exposed to tobacco smoke alone or in combination with a single dose of ethanol.ResultsThe highest levels of GSH were measured in the liver of smoke only exposed animals and in the lungs of rats exposed to smoke and alcohol. In the liver of animals treated with a single dose of alcohol or with smoke and alcohol, GST was significantly higher than in the group exposed to smoke only. SOD and catalase showed the highest activities in the livers of rats receiving a single dose of alcohol. High concentration of nitrites was observed in the lungs of animals treated with smoke and alcohol in combination, which corresponded to elevated protein nitrosylation in this group, whereas in the livers of these animals relatively low level of nitrites was accompanied with the lowest concentration of nitrosylated proteins. In the liver of alcohol only treated rats the highest nitrites corresponded to the highest protein nitrosylation. In the lungs of all treatment groups the range of DNA damage was higher, than the respective values in the livers. Although alcohol is not considered a specific toxicant to the lungs it was found to cause oxidative stress in this organ.ConclusionsThe obtained results suggest that in the ethanol-addicted rats combined exposure to smoke and alcohol differentially modulate endogenous antioxidant defense system and reactions to oxidative stress.  相似文献   

4.
糖尿病大鼠肾脏抗氧化防御系统机能的改变   总被引:1,自引:0,他引:1  
目的:探讨糖尿病对肾脏抗氧化防御机能的影响。方法:观察12周糖尿病大鼠肾皮质丙二醛(MDA)及谷胱甘肽(GSH)水平,以及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、谷胱甘肽S转移酶(GSH-ST)和过氧化氢酶(CAT)活性的变化。结果:糖尿病大鼠肾组织中SOD、CAT活性下降;GSH含量显著降低;MDA没有变化;GSH-PX活性却明显增强。结论:糖尿病大鼠肾组织抗氧化防御机能明显下降。  相似文献   

5.
This study investigated the effects of 9 days' smoking abstinence on psychophysiological stress reactions. The subjects were 40 female smokers; 20 of them intended to give up smoking in the course of the study, whereas the remaining 20 had no such intention. A first session was carried out before, a second and a third during days 3 and 9 of abstinence. The nonabstainers were tested at corresponding intervals. Each session consisted of a 30-min stress-coping phase with relaxation phases before and after. While performing a rapid information processing task (RIP) the subjects had to sustain electrical shocks which were, according to instructions, but not in fact, either avoidable (active coping) or not (passive coping). Generally, the active coping instruction produced greater responses to the RIP task than did the passive coping instruction for heart rate, systolic and diastolic blood pressure but not for finger pulse amplitude, thus resembling a beta-adrenergic stimulation. RIP processing rate was not affected, but the response rate (total of hits and commission errors) was greater during active than during passive coping. However, none of these stress reactions differed between abstainers and nonabstainers. On the other hand, both heart rate and the craving to smoke decreased significantly in the abstainer group across the 9 days. Thus, it is concluded that a deprivation of 1 h, 3 or 9 days has no differential effect on physiological stress reactions.  相似文献   

6.
7.
The objective of this study was to compare the short-term respiratory effects due to the inhalation of electronic and conventional tobacco cigarette-generated mainstream aerosols through the measurement of the exhaled nitric oxide (eNO). To this purpose, twenty-five smokers were asked to smoke a conventional cigarette and to vape an electronic cigarette (with and without nicotine), and an electronic cigarette without liquid (control session).  相似文献   

8.
BackgroundThe aim of our research was to evaluate some biochemical changes in blood during lamotrigine (LTG) monotherapy of adult patients with epilepsy, and to check possible associations between typical selenium status parameters and the frequency of seizures.MethodsThe study was performed by examining aspartate aminotransferase (AspAT), alanine aminotransferase (AlaAT), creatinine, ferric reducing ability of plasma (FRAP), serum uric acid (UA), uric-acid-independent FRAP (UAiFRAP), plasma glutathione peroxidase (GPX3), selenoprotein P (SelP), plasma superoxide dismutase (pSOD), 8-hydroxy-2’-deoxyguanosine (8-OHdG) in serum and urine, serum selenium (sSe) and zinc (sZn), in 22 adult patients with epilepsy and 22 healthy controls. Additionally, the levels of LTG were determined in patients.ResultspSOD activity was higher in the study group (5.32 ± 1.24 U/ml) compared with the controls (4.05 ± 0.92 U/ml, p = 0.008). No other statistical difference between patients and controls was found.ConclusionLack of difference in parameters other than SOD, particularly no difference in 8-OHdG concentrations between the patients treated with LTG compared to the control subjects suggests that these patients are at no particular risk of oxidative DNAdamage. In patients who are well or moderately well clinically controlled, selenium status parameters (sSe, GPX3, SelP) are not directly connected with the frequency of seizures.  相似文献   

9.
This study is intended to determine the effect of lead acetate on glutathione and its associated enzymes of rat brain. Wistar male rats were treated with lead acetate (500 ppm) through drinking water for a period of 8 weeks and parallel controls were maintained. They were sacrificed at the first, fourth and eighth week to isolate whole brains, which were separated into cerebellum, hippocampus, frontal cortex and brain stem. The data indicate enhanced (P < 0.05) glutathione peroxidase (G‐Px) activity at most of the intervals for cerebellum, frontal cortex and brain stem, suggesting conversion of GSH to GSSG, while the hippocampus showed decreased levels. In contrast, glutathione reductase (GR) decreased significantly (P < 0.05) in cerebellum, frontal cortex and brain stem at all intervals except the fourth week in frontal cortex and brain stem. Hippocampus exhibited a gradual and significant (P < 0.05) increase in GR activity. Glutathione‐S‐transferase (GSTase) activity increased with exposure time in all four brain tissues, showing protection against lead acetate toxicity. The GSH and GSSG levels correlated well with the activities of GPx, GR and GSTase in all four regions of the brain. Overall the results indicate that lead acetate affects glutathione‐related enzymes differentially and these changes can be attributed to differences in tissue susceptibility. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
Lawsone (2-hydroxy-1,4-naphthoquinone) is the active ingredient of henna (Lawsonia alba), the crushed leaves of which are used as a cosmetic dye. Application of henna can induce a severe hemolytic anemia, and lawsone is thought to be the causative agent. Administration of lawsone to rats has been shown to induce a hemolytic response that is associated with oxidative damage to erythrocytes. However, direct exposure of isolated erythrocytes to lawsone did not provoke oxidative damage, suggesting that lawsone must undergo extra-erythrocytic bioactivation in vivo. In the present study, the survival of rat 51Cr-labeled erythrocytes in vivo after in vitro exposure to lawsone and its hydroquinone form, 1,2,4-trihydroxynaphthalene (THN) has been examined. Neither lawsone nor THN were directly hemolytic or methemoglobinemic, even at high concentrations (>3 mM). Lawsone had no effect on erythrocytic GSH levels, whereas THN (3 mM) induced a modest depletion (approximately 30%). Cyclic voltammetry revealed that the lack of hemotoxicity of lawsone was associated with a poor capacity to undergo redox cycling. In contrast, ortho-substituted 1,4-naphthoquinones without a 2-hydroxy group, such as 2-methyl- and 2-methoxy-1,4-naphthoquinone, were redox active, were able to deplete GSH, and were direct-acting hemolytic agents. An oxidant stress-associated hemolytic response to lawsone could be provoked, however, if it was incubated with GSH-depleted erythrocytes. The data suggest that lawsone is a weak direct-acting hemolytic agent that does not require extra-erythrocytic metabolism to cause hemotoxicity. Thus, the hemolytic response to henna may be restricted to individuals with compromised antioxidant defenses.  相似文献   

11.
《Inhalation toxicology》2013,25(10):667-675
Context: Tobacco smoking represents a global public health threat, claiming approximately 5 million lives a year. Waterpipe tobacco use has become popular particularly among youth in the past decade, buttressed by the perception that the waterpipe “filters” the smoke, rendering it less harmful than cigarette smoke.

Objective: In this study, we examined the acute exposure of waterpipe smoking on lung inflammation and oxidative stress in mice, and compared that to cigarette smoking.

Materials and methods: Mice were divided into three groups; fresh air control, cigarette and waterpipe. Animals were exposed to fresh air, cigarette, or waterpipe smoke using whole body exposure system one hour daily for 7 days.

Results: Both cigarette and waterpipe smoke exposure resulted in elevation of total white blood cell count, as well as absolute count of neutrophils, macrophages, and lymphocytes (P < 0.01). Both exposures also elevated proinflammatory markers such as TNF-α and IL-6 in BALF (P < 0.05), and oxidative stress markers including GPx activity in lungs (P < 0.05). Moreover, waterpipe smoke increased catalase activity in the lung (P < 0.05). However, none of the treatments altered IL-10 levels.

Discussion and conclusion: Results of cigarette smoking confirmed previous finding. Waterpipe results indicate that, similar to cigarettes, exposure to waterpipe tobacco smoke is harmful to the lungs.  相似文献   

12.
An in vivo model in rat was developed by intraperitoneally administration of Fe-dextran to study oxidative stress triggered by Fe-overload in rat brain. Total Fe levels, as well as the labile iron pool (LIP) concentration, in brain from rats subjected to Fe-overload were markedly increased over control values, 6 h after Fe administration. In this in vivo Fe overload model, the ascorbyl (A)/ascorbate (AH?) ratio, taken as oxidative stress index, was assessed. The A/AH? ratio in brain was significantly higher in Fe-dextran group, in relation to values in control rats. Brain lipid peroxidation indexes, thiobarbituric acid reactive substances (TBARS) generation rate and lipid radical (LR) content detected by Electron Paramagnetic Resonance (EPR), in Fe-dextran supplemented rats were similar to control values. However, values of nuclear factor-kappaB deoxyribonucleic acid (NFκB DNA) binding activity were significantly increased (30%) after 8 h of Fe administration, and catalase (CAT) activity was significantly enhanced (62%) 21 h after Fe administration. Significant enhancements in Fe content in cortex (2.4 fold), hippocampus (1.6 fold) and striatum (2.9 fold), were found at 6 h after Fe administration. CAT activity was significantly increased after 8 h of Fe administration in cortex, hippocampus and striatum (1.4 fold, 86, and 47%, respectively). Fe response in the whole brain seems to lead to enhanced NF-κB DNA binding activity, which may contribute to limit oxygen reactive species-dependent damage by effects on the antioxidant enzyme CAT activity. Moreover, data shown here clearly indicate that even though Fe increased in several isolated brain areas, this parameter was more drastically enhanced in striatum than in cortex and hippocampus. However, comparison among the net increase in LR generation rate, in different brain areas, showed enhancements in cortex lipid peroxidation, without changes in striatum and hippocampus LR generation rate after 6 h of Fe overload. This information has potential clinical relevance, as it could be the key to understand specific brain damage occurring in conditions of Fe overload.  相似文献   

13.
14.
The aim of the present study was to investigate antioxidativity of the triphenylethylene antiestrogen toremifene. Toremifene and its structural analogues were studied for their ability to inhibit chain reactions of lipid peroxidation and to act as scavengers of free radicals in vitro, and the effects of toremifene were compared to those of the estrogens, tamoxifen and known antioxidants. Moreover, the in vivo antioxidativity of toremifene was tested in a long-term experiment with rats. The ability of toremifene to prevent lipid peroxidation was assayed in two different test systems. In the first assay (initiated with ascorbate/ADP-FeCl3, detection by the formation of TBA-reactive material) toremifene was found to act as an efficient membrane antioxidant with an IC50-value (18 μM) comparable to that of tamoxifen (26 μM) and α-tocopherol (43 μM). Toremifene derivatives 4-hydroxytoremifene (IC50 = 8 μM) and Fc 1159 (IC50 = 31 μM), as well as diethylstilbestrol (IC50 = 17 μM) were also active while estradiol showed only weak antioxidativity (IC50 = 300 μM) in this test system. In the other assay (peroxidation initiated with t-butylhydroperoxide, detection by luminol-enhanced chemiluminescence) toremifene prevented lipid peroxidation only at high concentrations (IC50 = 450 μM) but the metabolite 4-hydroxytoremifene (IC50 = 0.18 μM), estradiol (IC50 = 4.6 μM) and diethylstilbestrol (IC50 = 1.7 μM) showed potent antioxidant activity. The potency of 4-hydroxytoremifene even exeeded that of α-tocopherol (IC50 = 2.0 μM) and butylated hydroxyanisole (IC50 = 1.1 μM). Toremifene was found to have some superoxide anion but no peroxyl radical scavenging activity. Interestingly, diethylstilbestrol turned out to be a potent scavenger of peroxyl radicals. Treatment of female Sprague-Dawley rats with toremifene (12 or 48 mg/kg) was found to decrease serum levels of lipid peroxides. This was seen at various time points (2 days, 5 weeks, 6 and 12 months) during long-term administration of toremifene to rats, and results obtained with two different methods (diene conjugation, TBA-reactive material) gave similar results. The present study thus showed that (i) like steroidal estrogens and tamoxifen toremifene is a potent membrane antioxidant in vitro, (ii) the antioxidant action of toremifene is not due to scavenging of free radicals and, importantly, (iii) toremifene acts antioxidatively also in living organisms in vivo. Received: 10 February 1997 / Accepted: 27 May 1997  相似文献   

15.
16.
The aim of the present study was to investigate the ameliorative properties of propolis against the toxic effects of chromium (VI) by examining oxidative damage markers such as lipid peroxidation and the antioxidant defence system components in carp (Cyprinus carpio). The fish were exposed to sublethal concentrations of chromium. Propolis was simultaneously administered to chromium‐exposed fish. Treatment was continued for 28 days, and at the end of this period, blood and tissue (liver, kidney, spleen, and gill) samples were collected. Levels of malondialdehyde (MDA) and reduced glutathione (GSH) as well as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH‐Px) activities were determined in blood and tissues for measurement of oxidant–antioxidant status. The levels of MDA, as an index of lipid peroxidation, increased in blood and tissues. Antioxidant enzyme activities in blood and tissues were modified in chromium groups compared to controls. Simultaneous administration of propolis ameliorated these parameters. The present results suggest that administration of propolis might alleviate chromium‐induced oxidative stress. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 155–164, 2014.  相似文献   

17.
Objective: There has been an increase in the popularity of waterpipe tobacco smoking (WTS) worldwide, especially in the younger population, including asthma patients. In this study, we investigated the effects of waterpipe smoking on airway inflammation, cytokine levels and oxidative stress markers in an antigen-driven murine model of asthma.

Materials and methods: Balb/c mice were divided into four groups; (1) control (received fresh air, ovalbumin sensitization and saline challenge), (2) WTS (received WTS, ovalbumin sensitization and saline challenge), (3) Ova S/C (received fresh air, ovalbumin sensitization and ovalbumin challenge) and (4) simultaneous WTS and Ova S/C (received WTS, ovalbumin sensitization and ovalbumin challenge). Airway inflammatory cells were evaluated in the broncho-alveolar lavage fluid. Cytokines [interleukin (IL)-13, 10 and 18] and oxidative stress markers [superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx)] were evaluated in the lung homogenates.

Results: Chronic exposure to WTS significantly increased the number of airway inflammatory cells in mice, specifically: eosinophils, neutrophils, macrophages and lymphocytes. The level of IL-13 in the lungs was increased and the level of IL-10 was reduced (p?Chronic WTS potentiated the increase in inflammatory cells induced by Ova S/C (p?p?Conclusions: Chronic WTS exposure induced airway inflammation in control mice and enhanced airway inflammation in murine model of asthma.  相似文献   

18.
《Inhalation toxicology》2013,25(8):444-454
Abstract

Context: Inhalation of fine particulate matter (PM2.5) is associated with acute pulmonary inflammation and impairments in cardiovascular function. In many regions, PM2.5 is largely derived from diesel exhaust (DE), and these pathophysiological effects may be due in part to oxidative stress resulting from DE inhalation. The antioxidant glutathione (GSH) is important in limiting oxidative stress-induced vascular dysfunction. The rate-limiting enzyme in GSH synthesis is glutamate cysteine ligase and polymorphisms in its catalytic and modifier subunits (GCLC and GCLM) have been shown to influence vascular function and risk of myocardial infarction in humans.

Objective: We hypothesized that compromised de novo synthesis of GSH in Gclm?/+ mice would result in increased sensitivity to DE-induced lung inflammation and vascular effects.

Materials and methods: WT and Gclm?/+ mice were exposed to DE via inhalation (300?μg/m3) for 6?h. Neutrophil influx into the lungs, plasma GSH redox potential, vascular reactivity of aortic rings and aortic nitric oxide (NO?) were measured.

Results: DE inhalation resulted in mild bronchoalveolar neutrophil influx in both genotypes. DE-induced effects on plasma GSH oxidation and acetylcholine (ACh)-relaxation of aortic rings were only observed in Gclm?/+ mice. Contrary to our hypothesis, DE exposure enhanced ACh-induced relaxation of aortic rings in Gclm?/+ mice.

Discussion and conclusion: These data support the hypothesis that genetic determinants of antioxidant capacity influence the biological effects of acute inhalation of DE. However, the acute effects of DE on the vasculature may be dependent on the location and types of vessels involved. Polymorphisms in GSH synthesis genes are common in humans and further investigations into these potential gene-environment interactions are warranted.  相似文献   

19.
Objective: Worldwide popularity of waterpipe tobacco smoking has increased, including in pregnant women. This study investigates the effect of prenatal waterpipe tobacco smoke (WTS) exposure on airway inflammation in a murine model of asthma of adult offspring mice.

Materials and methods: Pregnant BALB/c mice were exposed to fresh air or WTS, using a whole-body exposure system that mimics human use during WTS. Adult male offspring mice were divided into; (1) control (prenatal fresh air, postnatal ovalbumin sensitization and saline challenge), (2) postnatal Ova S/C (prenatal fresh air, postnatal ovalbumin sensitization and challenge (Ova S/C)), (3) prenatal WTS (prenatal WTS, postnatal ovalbumin sensitization and saline challenge) and (4) prenatal WTS?+?postnatal Ova S/C. Cells from the bronchoalveolar lavage fluid, cytokines, and oxidative stress markers (superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and thiobarbituric acid reactive substances (TBARS)) from lung homogenates were evaluated.

Results: Prenatal WTS increased recruitment of cells in lungs and levels of SOD and catalase when compared to unexposed offspring’s. The levels of cytokines, GPx and TBARS were not affected by prenatal WTS. Prenatal WTS exposure and postnatal Ova S/C increased airway inflammation and activity of SOD compared to control and Ova S/C mice and reduced IL-18 levels compared to Ova S/C mice.

Discussion and conclusions: Prenatal exposure to WTS induced airway inflammation, further enhanced by a murine model of asthma in adult offspring. Prenatal exposure to WTS adversely affects the lung function of the offspring and careful strategies for increasing public awareness regarding the harmful effects of WTS during pregnancy is important.  相似文献   

20.
Context: Solanum xanthocarpum Schard. and Wendl. (Solanaceae) has been used in traditional Indian medicines for its antioxidant, anti-inflammatory, and antiasthmatic properties.

Objective: The present study demonstrates the antioxidant and hepatoprotective effects of S. xanthocarpum. On the basis of in vitro antioxidant properties, the active fraction from column chromatography of the methanol extract of S. xanthocarpum leaves (SXAF) was chosen as the potent fraction and used for hepatoprotective studies in rats.

Materials and methods: The antioxidant activity was evaluated by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and reducing power assays. Rats were pre-treated with 100 and 200?mg/kg b.w. of SXAF for 14?d with a single dose of CCl4 in the last day. Hepatoprotective properties were determined by serum biochemical enzymes, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), antioxidant enzymes (SOD, CAT, GSH, and GST), and histopathology studies.

Results: SXAF exhibited significant antioxidant activity in scavenging free radicals with IC50 values of 11.72?µg (DPPH) and 17.99?µg (ABTS). Rats pre-treated with SXAF demonstrated significantly reduced levels of serum LDH (1.7-fold), ALP (1.6-fold), and AST (1.8-fold). Similarly, multiple dose SXAF administration at 200?mg/kg b.w. demonstrated significantly enhanced levels of SOD (1.78?±?0.13), CAT (34.63?±?1.98), GST (231.64?±?14.28), and GSH (8.23?±?0.48) in liver homogenates. Histopathological examination showed lowered liver damage in SXAF-treated groups.

Discussion and conclusion: These results demonstrate that SXAF possesses potent antioxidant properties as well as hepatoprotective effects against CCl4-induced hepatotoxicity.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号