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  • 作者:

    Objective This study was designed to evaluate the toxic effects of Atrazine (ATZ) on the reproductive system of male rats.
    Methods Male Sprague-Dawley rats were exposed to ATZ by gavage at dosages of 0, 38.5, 77, and 154 mg/kg bw/day for 30 d. The toxic effects of ATZ to rats were assessed through histopathologcal observation, spermatozoa quality evaluation, testicular marker enzyme indicators, antioxidant capacity and reproductive hormone levels.
    Results Significant adverse effects on reproductive system were observed in rats exposed to ATZ at different dosages compared with 0 mg/kg group, including an irregular and disordered arrangement of the seminiferous epithelium in 154 mg/kg group;a decreased spermatozoa number and an increased spermatozoa abnormality rate in 77 and 154 mg/kg groups;decreased levels of acid phosphatase (ACP), alkaline phosphatase (AKP), lactic dehydrogenase (LDH), and succinate dehydrogenase (SDH) with the increasing of ATZ concentration; a decreased level of total antioxidant capacity (TAC) in a dose-dependent manner, and a decreased reduced glutathione (GSH) level and an increased malondialdehyde (MDA) content in 154 mg/kg group;and decreased serum levels of testosterone (T) and inhibin-B (INH-B) and an increased serum level of follicle stimulating hormone (FSH) in 77 and 154 mg/kg groups, and an increased serum level of luteinizing hormone (LH) in 154 mg/kg group.
    Conclusion These results suggested that relatively high doses of ATZ could exert reproductive toxicity of male rats.

  • 作者:

    Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression.
    Methods BALB/c mice were randomly divided into eight groups:saline;ovalbumin (OVA)-immunized;saline+DBP (0.45 mg/kg·d); saline+DBP (45 mg/kg·d); DBP (0.45 mg/kg·d) OVA-immunized; DBP (45 mg/kg·d) OVA-immunized; saline+hydrocortisone (30 mg/kg·d); and hydrocortisone (30 mg/kg·d)-exposed OVA-immunized. Behavior (e.g. open-field, tail suspension, and forced swimming tests), viscera coefficients (brain and spleen), oxidative damage [e.g. reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH)], as well as levels of IgE and IL-4, were then analyzed.
    Results In the saline and OVA groups, the degree of depression symptoms in mice increased with increasing DBP concentration. Additionally, the OVA-immunity groups were associated with more serious depressive behavior compared with the same exposure concentration in the saline group. Oxidative damage was associated with a dose-dependent increase in DBP in the different groups. IL-4 and IgE levels were associated with low-dose DBP stimulation, which changed to high-dose inhibition with increasing DBP exposure, possibly due to spleen injury seen at high DBP concentrations.
    Conclusion Development of an atopic allergy has the potential to increase the risk of depression in mice, and it seems that DBP helps OVA to exert its effect in our present model. Moreover, the results of our study implicate a certain connection between brain oxidative stress and depression, which deserves a further exploration.

  • 强化胰岛素治疗减轻2型糖尿病大鼠氧化应激

    作者:王德峰;孙力;李焰;陈兴起;刘红;王友明

    近年来的研究表明氧化应激(oxidative stress,OS)参与了糖尿病的发生发展.糖尿病存在着OS水平的升高,而机体的OS决定于活性氧(reactive oxygen species,BOS)及其导致的过氧化脂质产生增多与抗氧化防御系统中各种抗氧化酶的减少.本研究旨在观察强化胰岛素治疗对2型糖尿病大鼠OS的影响及其机制.

  • L-精氨酸对酒精性肝脂肪变大鼠肝组织NOS表达及氧应激的影响

    作者:田德安;洪捷敏;刘南植;王家駹

    目的:探讨L-精氨酸对酒精性肝脂肪变大鼠肝组织NOS表达及氧应激的影响.方法:采用在饮水中力A酒精的方法建立酒精性肝脂肪变动物模型.32只SD大鼠随机分成4组,每组8只.A,B组分别喂饲400 mL/L乙醇至16,20 wk;C组喂饲乙醇同B组,自17 wk起腹腔注射L-精氨酸;D组为正常对照组.B,D组自17 wk起腹腔注射等量的生理盐水.应用免疫组化和逆转录多聚酶链反应(RT-PCR)的方法检测肝组织中NOS的蛋白和mRNA表达,同时测定肝组织中NO,MDA,GSH,SOD含量,并观察肝组织病理变化.结果:A,B组肝组织出现了不同程度脂肪变性,B组更为显著(t=76.5,P<0.05).与D组相比,A,B组肝组织中NO,MDA含量、iNOS表达明显增高(P<0.01);GSH,SOD含量、eNOS表达明显降低(P<0.05).与B组相比,C组肝组织脂肪变性被逆转或明显减轻(t=62.5,P<0.05),NO含量无显著改变,MDA含量、iNOS表达明显降低(P<0.05);GSH,SOD含量及eNOS表达明显升高(P<0.05).结论:L-精氨酸对酒精性肝脂肪变的治疗作用可能与iNOS表达降低、eNOS表达升高以及氧应激减轻有关.

  • 心力衰竭心肌β_3肾上腺素能受体与氧化应激的关系

    作者:张颖;孔一慧;李为民

    心力衰竭为各种心脏疾病的终末期表现,是导致心脏病患者死亡的重要原因.全球每年有众多的心力衰竭患者,仅在中国每年就有4 000 000人,住院人次超过1 000 000例,占1.5%~2.0%.研究结果表明交感神经过度激活与心力衰竭发生、发展密切相关,是心力衰竭患者早神经体液变化之一.

  • 作者:

    Objective To observe the biological function of human 3-hydroxyisobutyrate dehydrogenase (HIBADH). Methods Human 3-hydroxyisobutyrate dehydrogenase (HIBADH, 3-hydroxy-2-methyl propanoate: NAD+oxidoreductase) recombinant protein was expressed inE. coli BL21,and puriifed by Ni+ column. The special antisera was obtained from rabbits immunized by this purified antigen. On the distribution of HIBADH, it was found that HIBADH over-expressed in the injured liver cells when serious hepatitis occurred. The phenomenon was conifrmed in the animal models of SD rats with acute liver cell injury induced by CCl4, but this phenomenon did not exist in the models induced by endotoxin combined with galactosamine. Further more, HIBADH’s overexpression in liver cells will induce cell necrosis through the pathway of oxidative stress. Results When the liver cells injured by drug or other chemical materials, HIBADH will be compensationally over-expressed for the deifciency of energy, so liver cells can make enough ATP through brand-chain amino acid catabolism. However, the overexpression of HIBADH will be harmful for liver cells through the product of much more active oxygens which will induce the cell necrosis. Conclusions HIBADH over-expression is a signal of the liver cell metabolism injury, and it can aggravate the liver cell injury through oxidative stress.

  • 作者:

    Objective To investigate the differences of clinical and biochemical characteristics between patients with liver cirrhosis induced by HBV infection combined with and without mild alcohol intake. Methods Data of patients with liver cirrhosis who were hospitalized in the First Hospital Afifliated to Xinjiang Medical University were retrospectively analyzed. Patients were divided into three groups: patients with liver cirrhosis induced by HBV infection and combined with mild alcohol intake, patients with HBV-related cirrhosis, and patients with alcohol-related cirrhosis. Biochemical detections including liver function, fasting lipid proifles, lipoprotein, kidney function, glucose, uric acid and regular blood tests were carried out and results were compared among three groups. Data were analyzed through STATA software and co-variant analysis. Results Total of 2 350 patients with liver cirrhosis were included, 732 patients had cirrhosis induced by HBV infection combined with mild alcohol intake, 1 316 patients had HBV-related liver cirrhosis, 302 patients had alcohol-related cirrhosis. The highest mean level of white cell count, mean corpuscular volume,γ-glutamyltranspeptidase and uric acid were observed in HBV infection combined with mild alcohol intake group. Multivariate regression analysis revealed that HBV infection, excessive alcohol intake, male and age were risk factors for hepatocellular carcinoma (HCC) in patients with liver cirrhosis. Conclusions HBV infection combined with mild alcoholic-related liver cirrhosis group showed the highest oxidative stress compared with alcoholic liver cirrhosis group, which suggested that mild alcohol intake may increase the incidence of liver cirrhosis in HBV infected patients and may not increase the incidence of HCC.

  • 作者:

    There are few studies on the neuroprotective effects of syringaldehyde in a rat model of cerebral ischemia. The study aimed to elucidate the mechanisms underlying the neuroprotective effects of syringaldehyde on ischemic brain cells. Rat models of cerebral ischemia were intraperitoneally administered syringaldehyde. At 6 and 24 hours after syringaldehyde administration, cell damage in the brain of cerebral ischemia rats was obviously reduced, superoxide dismutase activity and nuclear respiratory factor 1 expression in the brain tissue were markedly increased, malondi-adehyde level was obviously decreased, apoptosis-related cysteine peptidase caspase-3 and -9 immunoreactivity was obviously decreased, and neurological function was markedly improved. These ifndings suggest that syringaldehyde exerts neuroprotective effects on cerebral ischemia injury through anti-oxidation and anti-apoptosis.

  • 作者:

    In the present study, we transplanted adipose-derived mesenchymal stem cells into the hippo-campi of APP/PS1 transgenic Alzheimer’s disease model mice. Immunofluorescence staining revealed that the number of newly generated (BrdU+) cells in the subgranular zone of the dentate gyrus in the hippocampus was signiifcantly higher in Alzheimer’s disease mice after adipose-de-rived mesenchymal stem cell transplantation, and there was also a significant increase in the number of BrdU+/DCX+neuroblasts in these animals. Adipose-derived mesenchymal stem cell transplantation enhanced neurogenic activity in the subventricular zone as well. Furthermore, adipose-derived mesenchymal stem cell transplantation reduced oxidative stress and alleviated cognitive impairment in the mice. Based on these ifndings, we propose that adipose-derived mes-enchymal stem cell transplantation enhances endogenous neurogenesis in both the subgranular and subventricular zones in APP/PS1 transgenic Alzheimer’s disease mice, thereby facilitating functional recovery.

  • 作者:

    Flavonoids from the stems and leaves of Scutellaria baicalensis Georgi, an antioxidant, marked-ly improve memory impairments and neuronal injuries. In the present study, primary cortical neurons of rats were exposed to potassium cyanide to establish a model of in vitro neural cell apoptosis. Inhibition of apoptosis by lfavonoids from the stems and leaves of Scutellaria baical-ensis Georgi at concentrations of 18.98, 37.36, and 75.92μg/mL was detected using this model. These lfavonoids dramatically increased cell survival, inhibited cell apoptosis and excessive pro-duction of malondialdehyde, and increased the activities of superoxide dismutase, glutathione peroxidase, and Na+-K+-ATPase in primary cortical neurons exposed to potassium cyanide. The lfavonoids from the stems and leaves of Scutellaria baicalensis Georgi were originally found to have a polyhydric structure and to protect against cerebral hypoxia in in vitro and in vivo models, including hypoxia induced by potassium cyanide or cerebral ischemia. The present study suggests that lfavonoids from the stems and leaves of Scutellaria baicalensis Georgi exert neuroprotective effects via modulation of oxidative stress, such as malondialdehyde, superoxide dismutase, gluta-thione peroxidase and Na+-K+-ATPase disorders induced by potassium cyanide.

  • 作者:

    Alterations in embryonic neural stem cells play crucial roles in the pathogenesis of amyotrophic lateral sclerosis. We hypothesized that embryonic neural stem cells from SOD1G93A individuals might be more susceptible to oxidative injury, resulting in a propensity for neurodegeneration at later stages. In this study, embryonic neural stem cells obtained from human superoxide dis-mutase 1 mutant (SOD1G93A) and wild-type (SOD1WT) mouse models were exposed to H2O2. We assayed cell viability with mitochondrial succinic dehydrogenase colorimetric reagent, and measured cell apoptosis by lfow cytometry. Moreover, we evaluated the expression of the adenos-ine monophosphate-activated protein kinase (AMPK)α-subunit, paired box 3 (Pax3) protein, and p53 in western blot analyses. Compared with SOD1WT cells, SOD1G93A embryonic neural stem cells were more likely to undergo H2O2-induced apoptosis. Phosphorylation of AMPKαin SOD1G93A cells was higher than that in SOD1WT cells. Pax3 expression was inversely correlated with the phosphorylation levels of AMPKα. p53 protein levels were also correlated with AMPKαphosphorylation levels. Compound C, an inhibitor of AMPKα, attenuated the effects of H2O2. These results suggest that embryonic neural stem cells from SOD1G93A mice are more susceptible to apoptosis in the presence of oxidative stress compared with those from wild-type controls, and the effects are mainly mediated by Pax3 and p53 in the AMPKα pathway.

  • 作者:

    3β-Hydroxysteroid-Δ24 reductase (DHCR24) is a multifunctional enzyme that localizes to the endoplasmic reticulum and has neuroprotective and cholesterol-synthesizing activities. DHCR24 overexpression confers neuroprotection against apoptosis caused by amyloidβdeposition. hTe present study aimed to construct two recombinant adenoviruses driving DHCR24 expression specifically in neurons. Two SYN1 promoter DNA fragments were obtained from human (h) and rat (r). Recombinant Ad-r(h)SYN1-DHCR24 was transfected into AD-293, N2A (mouse neuroblastoma), and MIN6 (mouse pancreatic carcinoma) cells. Western blot analysis showed DHCR24 was specially expressed in 293 and N2A cells, but no speciifc band was found in MIN6 cells. hTis demonstrates that the recombinant adenoviruses successfully express DHCR24, and no expression is observed in non-neuronal cells. TUNEL assay results showed apoptosis was inhibited in adenovirus-transfected neurons. Detecting reactive oxygen species by immunolfu-orescence, we found that adenovirus transfection inhibits apoptosis through scavenging excess reactive oxygen species. Our ifndings show that the recombinant DHCR24 adenoviruses induce neuron-specific DHCR24 expression, and thereby lay the foundation for further studies on DHCR24 gene therapy for Alzheimer’s disease.

  • 作者:

    Recent studies have demonstrated that Notch-1 expression is increased in the hippocampus of Alzheimer’s disease patients. We speculate that Notch-1 signaling may be involved in PC12 cell apoptosis induced by amyloid beta-peptide (25-35) (Aβ25-35). In the present study, PC12 cells were cultured with different doses (0, 0.1, 1.0, 10 and 100 nmol/L) of N-[N-(3,5-Dilfuorophen-acetyl)-L-alanyl]-S-phenylglycine t-butyl ester, a Notch-1 signaling pathway inhibitor, for 30 minutes. Then cultured cells were induced with Aβ25-35 for 48 hours. Pretreatment of PC12 cells with high doses of N-[N-(3,5-Dilfuorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (> 10 nmol/L) prolonged the survival of PC12 cells after Aβ25-35 induction, decreased the expression of apoptosis-related proteins caspase-3, -8, -9, increased the activity of oxidative stress-related su-peroxide dismutase and catalase, inhibited the production of active oxygen, and reduced nuclear factor kappa B expression. This study indicates that the Notch-1 signaling pathway plays a pivotal role in Aβ25-35-induced PC12 apoptosis.

  • 作者:

    Alzheimer’s disease is a neurodegenerative disorder characterized by progressive cognitive impairment and neuropathology. Recent preclinical and epidemiological studies proposed statins as a possible therapeutic drug for Alzheimer’s disease, but the exact mechanisms of action are stil unknown. Biliverdin reductase-A is a pleiotropic enzyme involved in cel ular stress responses. It not only transforms biliverdin-IX alpha into the antioxidant bilirubin-IX alpha but its serine/threonine/tyrosine kinase activity is able to modulate cel signaling networks. We previously reported the beneficial effects of atorvastatin treatment on biliverdin reductase-A and heme oxygenase-1 in the brains of a well characterized pre-clinical model of Alzheimer’s disease, aged beagles, together with observed improvement in cognition. Here we extend our knowledge of the effects of atorvastatin on inducible nitric oxide synthase in parietal cortex, cerebel um and liver of the same animals. We demonstrated that atorvastatin treatment (80 mg/day for 14.5 months) to aged beagles selectively increased inducible nitric oxide synthase in the parietal cortex but not in the cerebel um. In contrast, inducible nitric oxide synthase protein levels were significantly decreased in the liver. Significant positive correlations were found between biliverdin reductase-A and inducible nitric oxide synthase as wel as heme oxygenase-1 protein levels in the parietal cortex. The opposite was observed in the liver. Inducible nitric oxide synthase up-regulation in the parietal cortex was positively associated with improved biliverdin reductase-A functions, whereas the oxidative-induced impairment of biliverdin reductase-A in the liver negatively affected inducible nitric oxide synthase expression, thus suggesting a role for biliverdin reductase-A in atorvastatin-dependent inducible nitric oxide synthase changes. Interestingly, increased inducible nitric oxide synthase levels in the parietal cortex were not associated with higher oxidative/nitrosative stress levels. We hypothesize that biliverdin reductase-A-dependent inducible nitric oxide synthase regulation strongly contributes to the cognitive improvement observed fol owing atorvastatin treatment.

  • 作者:

    The death of retinal ganglion cel s is a hal mark of many optic neurodegenerative diseases such as glaucoma and retinopathy. Oxidative stress is one of the major reasons to cause the cel death. Oligomeric proanthocyanidin has many health beneficial effects including antioxidative and neuro-protective actions. Here we tested whether oligomeric proanthocyanidin may protect retinal glion cel s against oxidative stress induced-apoptosis in vitro. Retinal ganglion cel s were treated with hydrogen peroxide with or without oligomeric proanthocyanidin. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that treating retinal ganglion cel line RGC-5 cel s with 20 μmol/L oligomeric proanthocyanidin significantly decreased the hydrogen peroxide (H 2 O 2 ) induced death. Results of flow cytometry and Hoechst staining demonstrated that the death of RGC-5 cel s was mainly caused by cel apoptosis. We further found that expression of pro-apoptotic Bax and caspase-3 were significantly decreased while anti-apoptotic Bcl-2 was greatly increased in H 2 O 2 damaged RGC-5 cel s with oligomeric proanthocyanidin by western blot assay. Furthermore, in retinal explant culture, the number of surviving retinal ganglion cel s in H 2 O 2-damaged retinal ganglion cel s with oligomeric proanthocyanidin was significantly increased. Our studies thus demonstrate that oligomeric proanthocyanidin can protect oxidative stress-injured retinal ganglion cel s by inhibiting apoptotic process.

  • 作者:

    Secondary degeneration occurs commonly in the central nervous system after traumatic injuries and following acute and chronic diseases, including glaucoma. A constellation of mechanisms have been shown to be associated with secondary degeneration including apoptosis, necrosis, autophagy, oxidative stress, excitotoxicity, derangements in ionic homeostasis and calcium influx. Glial cells, such as microglia, astrocytes and oligodendrocytes, have also been demon-strated to take part in the process of secondary injury. Partial optic nerve transection is a useful model which was established about 13 years ago. The merit of this model compared with other optic nerve injury models used for glaucoma study, including complete optic nerve transection model and optic nerve crush model, is the possibility to separate primary degeneration from secondary degeneration in location. Therefore, it provides a good tool for the study of secondary degeneration. This review will focus on the research progress of the mechanisms of secondary degeneration using partial optic nerve transection model.

  • 作者:

    Green tea polyphenols are strong antioxidants and can reduce free radical damage. To investigate their neuroprotective potential, we induced oxidative damage in spinal cord neurons using hy-drogen peroxide, and applied different concentrations (50-200 μg/mL) of green tea polyphenol to the cell medium for 24 hours. Measurements of superoxide dismutase activity, malondial-dehyde content, and expression of apoptosis-related genes and proteins revealed that green tea polyphenol effectively alleviated oxidative stress. Our results indicate that green tea polyphenols play a protective role in spinal cord neurons under oxidative stress.

  • 作者:

    Abnormal TAR DNA-binding protein 43 (TDP-43) inclusion bodies can be detected in the degener-ative neurons of amyotrophic lateral sclerosis. In this study, we induced chronic oxidative stress in-jury by applying malonate to cultured mouse cortical motor neurons. In the later stages of the ma-lonate insult, TDP-43 expression reduced in the nuclei and transferred to the cytoplasm. This was accompanied by neuronal death, mimicking the pathological changes in TDP-43 that are seen in patients with amyotrophic lateral sclerosis. Interestingly, in the early stages of the response to ma-lonate treatment, nuclear TDP-43 expression increased, and neurons remained relatively intact, without inclusion bodies or fragmentation. Therefore, we hypothesized that the increase of nuclear TDP-43 expression might be a pro-survival factor against oxidative stress injury. This hypothesis was confirmed by an in vitro transgenic experiment, in which overexpression of wild type mouse TDP-43 in cultured cortical motor neurons significantly reduced malonate-induced neuronal death. Our findings suggest that the loss of function of TDP-43 is an important cause of neuronal dege-neration, and upregulation of nuclear TDP-43 expression might be neuroprotective in amyotrophic lateral sclerosis.

  • 作者:

    In the hours to weeks following traumatic spinal cord injuries (SCI), biochemical processes are initiated that further damage the tissue within and surrounding the initial injury site:a process termed secondary injury. Acrolein, a highly reactive unsaturated aldehyde, has been shown to play a major role in the secondary injury by contributing signiifcantly to both motor and sensory deif-cits. In particular, efforts have been made to elucidate the mechanisms of acrolein-mediated dam-age at the cellular level and the resulting paralysis and neuropathic pain. In this review, we will highlight the recent developments in the understanding of the mechanisms of acrolein in motor and sensory dysfunction in animal models of SCI. We will also discuss the therapeutic beneifts of using acrolein scavengers to attenuate acrolein-mediated neuronal damage following SCI.

  • 作者:

    Iron overload can lead to cytotoxicity, and it is a risk factor for diabetic peripheral neuropathy. However, the underlying mechanism remains unclear. We conjectured that iron overload-induced neurotoxicity might be associated with oxidative stress and the NF-E2-related factor 2 (Nrf2)/ARE signaling pathway. As an in vitro cellular model of diabetic peripheral neuropathy, PC12 cells ex-posed to high glucose concentration were used in this study. PC12 cells were cultured with ferric ammonium citrate at different concentrations to create iron overload. PC12 cells cultured in ferric ammonium citrate under high glucose concentration had significantly low cellviability, a high rate of apoptosis, and elevated reactive oxygen species and malondialdehyde levels. These changes were dependent on ferric ammonium citrate concentration. Nrf2 mRNA and protein expression in the fer-ric ammonium citrate groups were inhibited markedly in a dose-dependent manner. Al changes could be inhibited by addition of deferoxamine. These results indicate that iron overload aggravates oxidative stress injury in neural cells under high glucose concentration and that the Nrf2/ARE sig-naling pathway might play an important role in this process.

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