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1.
The small intestine is known to be particularly sensitive to radiation, and the major limiting factor of radiotherapy is the gastrointestinal syndrome that subsequently develops after its administration. The detrimental effects of radiation are mostly mediated via the overproduction of reactive oxygen species (ROS), especially the hydroxyl radical (·OH). Because hydrogen is a selective ·OH scavenger, we hypothesized that hydrogen might exert a protective effect against radiation-induced intestinal damage. Herein, radiation models were built both in mice and in an intestinal crypt epithelial cell (IEC-6) line. In the animal experiment, we demonstrated that hydrogen-rich saline significantly reduced radiation-induced intestinal mucosal damage, improved intestinal function, and increased the survival rate. In addition, radiation-induced oxidative stress damage and systemic inflammatory response were also mitigated by hydrogen treatment. Moreover, hydrogen treatment decreased cell apoptosis and maintained intestinal epithelial cell proliferation in mice. In vitro experiments using the IEC-6 cell line showed that hydrogen-rich medium significantly inhibited ROS formation, maintained cell viability, and inhibited cell apoptosis. Importantly, hydrogen treatment prevented mitochondrial depolarization, cytochrome c release, and activity of caspase-3, caspase-9, and PARP. Moreover, the decreased expression of Bcl-xl and Bcl-2 and the increased expression of Bax protein were also blocked by hydrogen treatment. In conclusion, our study concurrently demonstrated that hydrogen provides an obviously protective effect on radiation-induced intestinal and cell injuries. Our work demonstrated that this protective effect might be due to the blockage of the mitochondrial apoptotic pathway.  相似文献   

2.
The adverse effects of lead nitrate (LN) and the preventive role of sodium selenite were investigated in diabetic and non-diabetic rat blood by measuring trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) also by evaluating DNA damage with comet assay. LN increased the levels of MDA, tail DNA%, mean tail length and tail moment, decreased the enzymes activities, FRAP and TEAC values. In sodium selenite + LN group, we observed the protective effect of sodium selenite on examining parameters. Diabetes caused alterations on these parameters, too. We found that sodium selenite did not protect against diabetes caused damages. As a result, LN caused toxic effects on blood cells and sodium selenite alleviated this toxicity but it did not show preventive effect against diabetes. Also, LN caused more harmfull effects in diabetic groups than non-diabetic groups.  相似文献   

3.
Exposure of mice to single-walled carbon nanotubes (SWCNTs) induces an unusually robust pulmonary inflammatory response with an early onset of fibrosis, which is accompanied by oxidative stress and antioxidant depletion. The role of specific components of the antioxidant protective system, specifically vitamin E, the major lipid-soluble antioxidant, in the SWCNT-induced reactions has not been characterized. We used C57BL/6 mice, maintained on vitamin E-sufficient or vitamin E-deficient diets, to explore and compare the pulmonary inflammatory reactions to aspired SWCNTs. The vitamin E-deficient diet caused a 90-fold depletion of alpha-tocopherol in the lung tissue and resulted in a significant decline of other antioxidants (GSH, ascorbate) as well as accumulation of lipid peroxidation products. A greater decrease of pulmonary antioxidants was detected in SWCNT-treated vitamin E-deficient mice as compared to controls. Lowered levels of antioxidants in vitamin E-deficient mice were associated with a higher sensitivity to SWCNT-induced acute inflammation (total number of inflammatory cells, number of polymorphonuclear leukocytes, released LDH, total protein content and levels of pro-inflammatory cytokines, TNF-alpha and IL-6) and enhanced profibrotic responses (elevation of TGF-beta and collagen deposition). Exposure to SWCNTs markedly shifted the ratio of cleaved to full-length extracellular superoxide dismutase (EC-SOD). Given that pulmonary levels of vitamin E can be manipulated through diet, its effects on SWCNT-induced inflammation may be of practical importance in optimizing protective strategies.  相似文献   

4.
Plastic products are widely used in different applications. Thus, exposure of human and other organisms to these products may affect their biological system. The current study was conducted to investigate the potential deleterious effect of Polysterene nanoparticles (PS-NPs) on the liver and to state the cellular and molecular mechanisms associated with exposure to PS-NPs.30 male rats were divided randomly and equally into 3 groups; control (distilled water), low dose (3 mg/kg/day) and high dose (10 mg/kg/day) exposed group via oral gavage for 5 successive weeks. PS-NPs caused elevation in ALT, AST and MDA, upregulation of apoptosis-related genes and significant decrease in GSH and mRNA expression for antioxidant-related genes (Nrf-2 and GPx). Moreover, alterations in hepatic tissue architecture and positive caspase-3 expression was noticed in a dose- dependent manner. Collectively, PS-NPs can induce hepatoxicity in rats in a dose dependent manner, so the health risk of PS-NPs should not be ignored.  相似文献   

5.
Due to the intensive commercial application of silver nanoparticles (Ag NPs), risk assessment of this nanoparticle is of great importance. Our previous in vitro study demonstrated that Ag NPs caused DNA damage and apoptosis in mouse embryonic stem cells and fibroblasts. However, toxicity of Ag NPs in vivo is largely lacking. This study was undertaken to examine the toxic effects of well-characterized polysaccharide coated 10 nm Ag NPs on heat shock stress, oxidative stress, DNA damage and apoptosis in Drosophila melanogaster. Third instar larvae of D. melanogaster were fed a diet of standard cornmeal media mixed with Ag NPs at the concentrations of 50 and 100 μg/ml for 24 and 48 h. Ag NPs up-regulated the expression of heat shock protein 70 and induced oxidative stress in D. melanogaster. Malondialdehyde level, an end product of lipid peroxidation was significantly higher while antioxidant glutathione content was significantly lower in Ag NPs exposed organisms. Activities of antioxidant enzyme superoxide dismutase and catalase were also significantly higher in the organisms exposed to Ag NPs. Furthermore, Ag NPs up-regulated the cell cycle checkpoint p53 and cell signaling protein p38 that are involved in the DNA damage repair pathway. Moreover, activities of caspase-3 and caspase-9, markers of apoptosis were significantly higher in Ag NPs exposed organisms. The results indicate that Ag NPs in D. melanogaster induce heat shock stress, oxidative stress, DNA damage and apoptosis. This study suggests that the organism is stressed and thus warrants more careful assessment of Ag NPs using in vivo models to determine if chronic exposure presents developmental and reproductive toxicity.  相似文献   

6.
The wide application of zinc oxide nanoparticles (ZnO NPs) in cosmetics, paints, biosensors, drug delivery, food packaging and as anticancerous agents has increased the risk of human exposure to these NPs. Earlier in vitro and in vivo studies have demonstrated a cytotoxic and genotoxic potential of ZnO NPs. However, there is paucity of data regarding their immunomodulatory effects. Therefore, the present study was aimed to investigate the immunotoxic potential of ZnO NPs using human monocytic cell line (THP-1) as model to understand the underlying molecular mechanism. A significant (p < 0.01) increase in pro-inflammatory cytokines (TNF-α and IL-1β) and reactive oxygen species (ROS) was observed with a concomitant concentration dependent (0.5, 1, 5, 10, 15 and 20 μg/mL) decrease in the glutathione (GSH) levels as compared to control. The expression levels of mitogen activated protein kinase (MAPK) cascade proteins such as p-ERK1/2, p-p38 and p-JNK were also significantly (p < 0.05, p < 0.01) induced. Also, at the concentration tested, NPs induced DNA damage as assessed by the Comet and micronucleus assays. Our data demonstrated that ZnO NPs induce oxidative and nitrosative stress in human monocytes, leading to increased inflammatory response via activation of redox sensitive NF-κB and MAPK signalling pathways.  相似文献   

7.
ObjectiveTo investigate the effect of lead selenide nanoparticles (nano PbSe) on kidney in rats.MethodSpecific pathogen free SD rats were randomly divided into 4 groups (8 rats/group), and injected with of 0 mg/kg (control group), 10 mg/kg (low dose group), 20 mg/kg (middle dose group), or 30 mg/kg (high dose group) nano PbSe respectively. Seven weeks after injection, the serum was taken from rats for the detection of blood urea nitrogen (BUN), creatinine (Cr) and uric acid (UA). Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) levels were detected using renal tissue homogenate. Pathological examination was performed on kidney sections.ResultsThe levels of BUN and Cr in three exposure groups were significantly increased compared with those of control group. Levels of UA in middle dose and high dose group were higher than those in the control group. Levels of SOD, GSH-Px and T-AOC in three exposure groups were markedly decreased compared with those in the control group. Levels of MDA in three exposure groups were higher than those in the control group. Pathological changes at different levels of kidneys were observed, and the damage was more serious with the increase of concentration.ConclusionsNano PbSe can lead to oxidative damage to the kidney, with the toxicity positively correlates to the dosage.  相似文献   

8.
The aim of the study was to evaluate time course and dose dependence of peroxidative damage induced by tert-butyl hydroperoxide (tBHP) in rat hepatocytes cultured in suspension and in monolayer. At the lowest (0.1 mM) concentration, decrease of cytosolic glutathione and discharge of mitochondrial membrane potential (MMP) could be detected. Significant increases in leakage of lactate dehydrogenase and in malondialdehyde concentrations together with decrease of pyruvate-dependent respiration were detected at higher tBHP concentrations (above 0.5 mM) and after longer periods of incubation. Changes in plasma membrane integrity were observed at 1 mM concentration of tBHP. Succinate-dependent oxidation was most resistant to peroxidative damages. Opening of the mitochondrial permeability transition pore was responsible for the discharge of mitochondria membrane potential. In the presence of cyclosporine A and succinate, the membrane potential could be restored. Our data showed that the most sensitive indicators of the peroxidative damage are changes of cytosolic glutathione concentration and MMP.  相似文献   

9.
The effect of cigarette smoke exposure on lungs of rat pups was evaluated. Animals were exposed to passive cigarette smoke during 3 weeks and a number of toxicological parameters in lung of pups were examined, such as lipid peroxidation, δ-aminolevulic acid dehydratase (δ-ALA-D) activity, components of the enzymatic antioxidant defenses (superoxide dismutase (SOD) and catalase activities) and non-enzymatic antioxidant defenses (Vitamin C and non-protein thiol (NPSH) levels). Furthermore, a possible protective effect of diphenyl diselenide, (PhSe)2, was studied. The results demonstrated an increase in lipid peroxidation, an inhibition of δ-ALA-D activity, a reduction of Vitamin C and NPSH levels induced by cigarette smoke exposure, indicating damage in lungs of rat pups. Oral administration of (PhSe)2 (0.5 mg/kg) restored TBARS levels, non-enzymatic antioxidant defenses and activity of δ-ALA-D. These results indicated that exposure to cigarette smoke enhanced oxidative stress, thereby disturbing the tissue defense system. (PhSe)2 protected against oxidative damage induced by cigarette smoke exposure in lung of rat pups.  相似文献   

10.
Phytochemicals such as polyphenols and carotenoids are gaining importance because of their contribution to human health and their multiple biological effects such as antioxidant, antimutagenic, anticarcinogenic and cytoprotective activities and other therapeutic properties. Mango peel is a major by-product in pulp industry and it contains various bioactive compounds like polyphenols, carotenoids and others. In the present study, the protective effect of peel extracts of unripe and ripe mango fruits of two varieties namely, Raspuri and Badami on hydrogen peroxide induced hemolysis, lipid peroxidation, degradation of membrane proteins and its morphological changes are reported. The oxidative hemolysis of rat erythrocytes by hydrogen peroxide was inhibited by mango peel extract in a dose dependent manner. The IC50 value for lipid peroxidation inhibition on erythrocyte ghost membrane was found to be in the range of 4.5–19.3 μg gallic acid equivalents. The mango peel extract showed protection against membrane protein degradation caused by hydrogen peroxide. Morphological changes to erythrocyte membrane caused by hydrogen peroxide were protected by mango peel extract. The results demonstrated that mango peel extracts protected erythrocytes against oxidative stress and may impart health benefits and it could be used as a valuable food ingredient or a nutraceutical product.  相似文献   

11.
目的 探讨铅和噪声联合作用对工人的血清超氧化物歧化酶(SOD)、丙二醛(MDA)含量的影响.方法 选择年龄、工龄及接触噪声强度相近的A(铅和噪声联合作用组)、B(单纯噪声组)两组工人,测定血SOD、MDA含量,同时测定血铅含量,并比较两组数据差异.结果 A、B两组工人血SOD值分别为(65.2±16.3) U/ml、(63.8±13.9) U/ml,两组工人血SOD值无明显差异(P>0.05);A、B两组工人血MDA含量分别为(6.81±3.12)nmol/ml、(5.02±2.36)nmol/ml,两组工人血MDA含量差异有统计学意义(P<0.05).结论 铅和噪声联合作用可加重机体自由基损害和脂质过氧化.  相似文献   

12.
Neuropeptide S (NPS) and its receptor were recently discovered in the central nervous system. In rodents, NPS promotes hyperlocomotion, wakefulness, anxiolysis, anorexia, and analgesia and enhances memory when injected intracerebroventricularly (i.c.v.). Herein, NPS at different doses (0.01, 0.1 and 1 nmol) was i.c.v. administered in mice challenged with pentylenetetrazole (PTZ; 60 mg/kg) repeatedly injected. Aiming to assess behavioral alterations and oxidative damage to macromolecules in the brain, NPS was injected 5 min prior to the last dose of PTZ. The administration of NPS only at 1 nmol increased the duration of seizures evoked by PTZ, without modifying frequency and latency of seizures. Biochemical analysis revealed that NPS attenuated PTZ-induced oxidative damage to proteins and lipids in the hippocampus and cerebral cortex. In contrast, the administration of NPS to PTZ-treated mice increased DNA damage in the hippocampus, but not cerebral cortex. In conclusion, this is the first evidence of the potential proconvulsive effects of NPS in mice. The protective effects of NPS against lipid and protein oxidative damage in the mouse hippocampus and cerebral cortex evoked by PTZ-induced seizures are quite unexpected. The present findings were discussed analyzing the paradoxical effects of NPS: facilitation of convulsive behavior and protection against oxidative damage to lipids and proteins.  相似文献   

13.
This study was to investigate the effects of ascorbic acid on the hippocampus of suckling rats in the presence of lead (Pb)-induced oxidative stress. Pregnant Sprague-Dawley rats received treatment with drinking water, divided into three groups, as follows: (1) distilled water; (2) 0.2% Pb; (3) 0.2% Pb+ascorbic acid (100mg/kg/day). Rat pups were euthanized at the age of 21days and their brain tissue was examined using light microscopy. Protein levels of Cu/Zn superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD), and catalase (CAT) in the hippocampus were determined by Western blotting. We found a significant decrease in levels of Cu/Zn SOD and Mn SOD among Pb-exposed pups. Ascorbic acid supplementation appeared to negate the decrease in protein levels for Cu/Zn SOD and Mn SOD. In the case of CAT, there was no effect from Pb administration alone and Pb plus ascorbic acid appeared to increase the levels. In histopathology, ascorbic acid decreased the number of damaged cells in cornu ammonis areas CA1, CA3, and the dentate gyrus (DG) in hippocampus. Our results showed that administration of ascorbic acid during pregnancy and lactation could ameliorate some of the oxidative damage induced by Pb exposure in the developing rat hippocampus.  相似文献   

14.
This study aimed to investigate the potential molecular mechanism underlying radon-induced lung damage. Our results showed that long-term radon exposure induced mitochondrial damage and redox imbalance in BEAS-2B cells and a time-dependent lung pathological injury in mice. The activation of Nrf-2 and its down-stream antioxidants, and the gene expression of the indicated markers at different stages of autophagy were found to be induced with the increasing of radon exposure time. Changes in the gene expression of PINK-1, Parkin, and p62 induced by radon showed differences in mechanisms of mitophagy activation and profiles of autophagic flux between BEAS-2B cells and mice. Our findings not only demonstrated that long-term radon exposure induced damages to bronchial epithelial cells and the mice lung through increasing oxidative stress, decreasing mitochondrial function and activating mitophagy with different profiles of autophagic flux, but also revealed Nrf-2 as a central regulator of mitochondrial homeostasis and lung damage.  相似文献   

15.
目的 观察MNNG亚慢性暴露对大鼠血清肿瘤坏死因子-α(TNF-α)、白细胞介素6(IL-6)、白介素1β(IL-1β)含量及食管组织结构的影响.方法 65只SPF级雄性Wistar大鼠随机分为生理盐水对照组、80、120、160和200 μg/ml MNNG染毒组,每组13只.对照组大鼠采用等量生理盐水灌胃,实验组大...  相似文献   

16.
Chronic inhalation of high concentrations of respirable quartz particles has been implicated in various lung diseases including lung fibrosis and cancer. Generation of reactive oxygen species (ROS) and oxidative stress is considered a major mechanism of quartz toxicity. Curcumin, a yellow pigment from Curcuma longa, has been considered as nutraceutical because of its strong anti-inflammatory, antitumour and antioxidant properties. The aim of our present study was to investigate whether curcumin can protect lung epithelial cells from the cytotoxic, genotoxic and inflammatory effects associated with quartz (DQ12) exposure. Electron paramagnetic resonance (EPR) measurements using the spin-trap DMPO demonstrated that curcumin reduces hydrogen peroxide-dependent hydroxyl-radical formation by quartz. Curcumin was also found to reduce quartz-induced cytotoxicity and cyclooxygenase 2 (COX-2) mRNA expression in RLE-6TN rat lung epithelial cells (RLE). Curcumin also inhibited the release of macrophage inflammatory protein-2 (MIP-2) from RLE cells as observed upon treatment with interleukin-1 beta (IL-1beta) and tumour necrosis factor-alpha (TNFalpha). However, curcumin failed to protect the RLE cells from oxidative DNA damage induced by quartz, as shown by formamidopyrimidine glycosylase (FPG)-modified comet assay and by immunocytochemistry for 8-hydroxydeoxyguanosine. In contrast, curcumin was found to be a strong inducer of oxidative DNA damage itself at non-cytotoxic and anti-inflammatory concentrations. In line with this, curcumin also enhanced the mRNA expression of the oxidative stress response gene heme oxygenase-1 (ho-1). Curcumin also caused oxidative DNA damage in NR8383 rat alveolar macrophages and A549 human lung epithelial cells. Taken together, these observations indicate that one should be cautious in considering the potential use of curcumin in the prevention or treatment of lung diseases associated with quartz exposure.  相似文献   

17.
Biodegradable micro/nanoparticles generated from PLGA have recently attracted attention due to their clinically proven biocompatibility, especially for immunization purposes. These polymeric particulate delivery systems are able to present antigens and activate both humoral and cellular responses. Many studies have discussed the ideal size of these particles in contributing to the generation of the different types of immune response. However, these studies do not demonstrate the effect of micro or nanoparticles, without any encapsulated bioactive, on phagocytic cells after the uptake process. In this context, the aim of this study was to analyze the in vitro inflammatory behavior of J774 murine macrophages after particles' uptake, since nano/microparticles per se can differently activate phagocytic cells, using or not appropriate receptors, inducing distinct inflammatory responses. An o/w emulsion solvent extraction–evaporation method was chosen to prepare the particles. We determined their diameters, zeta potential and morphology. Fluorescent particles' uptake by J774 murine “macrophage-like” cells was also analyzed. To evaluate the in vitro inflammatory profile of these cells after micro or nanoparticles' uptake, we conducted NF-κB translocation assay by confocal microscopy and also determined the pro-inflammatory cytokines production provoked by the particles.  相似文献   

18.
Oxidative stress and oxidative damage in chemical carcinogenesis   总被引:2,自引:0,他引:2  
Reactive oxygen species (ROS) are induced through a variety of endogenous and exogenous sources. Overwhelming of antioxidant and DNA repair mechanisms in the cell by ROS may result in oxidative stress and oxidative damage to the cell. This resulting oxidative stress can damage critical cellular macromolecules and/or modulate gene expression pathways. Cancer induction by chemical and physical agents involves a multi-step process. This process includes multiple molecular and cellular events to transform a normal cell to a malignant neoplastic cell. Oxidative damage resulting from ROS generation can participate in all stages of the cancer process. An association of ROS generation and human cancer induction has been shown. It appears that oxidative stress may both cause as well as modify the cancer process. Recently association between polymorphisms in oxidative DNA repair genes and antioxidant genes (single nucleotide polymorphisms) and human cancer susceptibility has been shown.  相似文献   

19.
Lysergic acid diethylamide (LSD), a classical hallucinogen, was used as a popular and notorious substance of abuse in various parts of the world. Its abuse could result in long-lasting abnormalities in retina and little is known about the exact mechanism. This study was to investigate the effect of LSD on macrophage activation state at non-toxic concentration and its resultant toxicity to photoreceptor cells. Results showed that cytotoxicity was caused by LSD on 661?W cells after co-culturing with RAW264.7 cells. Treatment with LSD-induced RAW264.7 cells to the M1 phenotype, releasing more pro-inflammatory cytokines, and increasing the M1-related gene expression. Moreover, after co-culturing with RAW264.7 cells, significant oxidative stress in 661?W cells treated with LSD was observed, by increasing the level of malondialdehyde (MDA) and reactive oxygen species (ROS), and decreasing the level of glutathione (GSH) and the activity of superoxide dismutase (SOD). Our study demonstrated that LSD caused photoreceptor cell damage by inducing inflammatory response and resultant oxidative stress, providing the scientific rationale for the toxicity of LSD to retina.  相似文献   

20.
Lead (Pb) is an extremely poisonous, non-essential trace element and toxicity develops in humans following frequent exposure to the heavy metal in polluted environmental and occupational settings. Pb induces hepatic damage through the depletion of the antioxidant system, enhancing cellular oxidative stress and stimulation of proinflammatory cytokines. Although the antioxidant and anti-inflammatory actions of vitamin D3 (VD3) are well-established, a minority of studies measured the protective actions of VD3 against Pb toxicity. Therefore, this work studied the effects of vitamin VD3 therapy on the fundamental molecular basis underlying hepatic injury induced by chronic Pb toxicity. Twenty-four adult male rats were distributed equally into the negative controls (NC), positive controls (PC) and VD3 groups. While both the PC and VD3 groups received Pb-acetate in drinking water (1000 mg/L) for four weeks, the latter group also received intramuscular VD3 injections (1000 IU/kg; 3 days/week) simultaneously with Pb. The liver enzymes together with the serum and hepatic tissue Pb concentrations increased markedly in the PC group compared with the NC group. Pb toxicity also drastically induced hepatocyte apoptosis/necrosis, increased the hepatic tissue concentrations of malondialdehyde and the pro-inflammatory cytokines (TGF-β, IL-4 & TNF-α) as well as reduced the anti-oxidative enzymes (GSH, GPx & CAT) and the anti-inflammatory cytokine, IL-10, compared with the NC group. Pb also significantly decreased the serum concentrations of VD3 and Ca2+. Additionally, the hepatic expressions of VD receptor, Cyp24a1 enzyme, L-type Ca2+-channel, calbindin-D28k & -D29k, calmodulin and calmodulin-dependent protein kinase II were significantly upregulated, whereas the VD binding protein, CYP2R1 enzyme and T-type Ca2+-channel were markedly inhibited at the gene and protein levels following Pb intoxication. VD3 alleviated the hepatic damage, inhibited the oxidative stress and pro-inflammatory molecules as well as upregulated the anti-oxidant and anti-inflammatory markers and restored the expression of the VD/Ca2+ regulatory molecules compared with the PC group. VD3 supplementation discloses promising protective effects against Pb-induced hepatic damage, through its anti-inflammatory and antioxidant actions as well as by modulating the hepatocyte calcium homeostatic molecules.  相似文献   

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