BACKGROUND: Brief exposure to the anesthetic sevoflurane results in delayed neuroprotection, However, few studies have addressed delayed neuroprotection after preconditioning with a single administration of sevoflura...BACKGROUND: Brief exposure to the anesthetic sevoflurane results in delayed neuroprotection, However, few studies have addressed delayed neuroprotection after preconditioning with a single administration of sevoflurane. OBJECTIVE: To explore the relationship between a single preconditioning administration of sevoflurane and reactive oxygen species production and protein kinase C-epsilon (PKC-ε ) translocation. DESIGN, TIME, AND SETTING: The randomized, controlled, animal experiment was conducted at the Central Laboratory, Xiangya Hospital, Central South University, China from November 2007 to April 2008. MATERIALS: A total of 120 healthy, male, Sprague Dawley rats were equally and randomly assigned into five groups: sham operation, ischemia/reperfusion, sevoflurane, 2-mercaptopropionylglycine (2-MPG, a selective reactive oxygen species scavenger) + sevoflurane (MPG + sevoflurane), and MPG. Sevoflurane (Baxter, USA) and MPG (Sigma, USA) were used in this study. METHODS: Intervention consisted of three procedures. (1) MPG injection: a selective reactive oxygen species scavenger, MPG (20 mg/kg), was infused into the rat caudal vein in the MPG and MPG + sevoflurane groups. (2) Sevoflurane preconditioning: 30 minutes following MPG injection, rats in the sevoflurane and MPG + sevoflurane groups breathed a mixed gas of 2.4% sevoflurane and 97.6% oxygen for 60 minutes. Rats in the sham operation, ischemia/reperfusion, and MPG groups breathed 100% pure oxygen for 60 minutes. (3) IschemiaJreperfusion: 24 hours after sevoflurane or pure oxygen preconditioning, middle cerebral artery occlusion models were established in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups. Following 2 hours ischemia/6 hours and 24 hours reperfusion, the carotid artery was separated, but the middle cerebral artery was not occluded, in the sham operation group. MAIN OUTCOME MEASURES: In the ischemic hemisphere, PKC-ε translocation in the rat parietal cortex was measured by Western blot analysis. Infarct volume was calculated using the TTC assay. Neurological deficits were evaluated in rats using a scoring system of 8 points. RESULTS: After 6 hours reperfusion, the ratio of PKC-ε in membrane/(cytosol + membrane) was significantly less in the sham operation group than in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane), and MPG groups (P 〈 0.05). The ratio of PKC-ε in membrane/(cytosol + membrane) was significantly greater in the sevoflurane group than in the sham operation, ischemia/reperfusion, MPG + sevoflurane, and MPG groups (P 〈 0.05). No significant differences were observed in the ischemiaJreperfusJon, M PG + sevoflurane, and MPG groups (P 〉 0.05). Following 24 hours reperfusion, the ratio of PKC-ε in membrane/(cytosol + membrane) was significantly less in the sham operation group than in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups (P 〈 0.05). No significant differences were detected in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups (P 〉 0.05). Compared with the ischemia/reperfusion, MPG + sevoflurane, and MPG groups, infarct volume was significantly smaller, and neurological deficits were significantly improved, in the sevoflurane group (P 〈 0.05). No significant differences in infarct volume and neurological deficits were observed among the ischemia/reperfusion, MPG + sevoflurane, and MPG groups (P 〉 0.05). Infarcts or neurological deficits were not detected in the sham operation group. CONCLUSION: A single preconditioning administration of sevoflurane reduced infarct volumes and improved neurological deficits in ischemic rats. Delayed neuroprotection may be mediated by reactive oxygen species and correlated to PKC- ε activation.展开更多
BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been prop...BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC.展开更多
AIM:To investigate the role of hepatitis B virus X-protein(HBx)-induced reactive oxygen species(ROS)on liver carcinogenesis in HBx transgenic mice and HepG2-HBx cells.METHODS:Cell growth rate was analyzed,and through ...AIM:To investigate the role of hepatitis B virus X-protein(HBx)-induced reactive oxygen species(ROS)on liver carcinogenesis in HBx transgenic mice and HepG2-HBx cells.METHODS:Cell growth rate was analyzed,and through western blotting,mitogenic signaling was observed.Endogenous ROS from wild and HBx transgenic mice and HepG2-Mock and HBx cells were assayed by FACS-calibur.Identification of oxidized and reduced phosphatase and tensin homolog(PTEN)was analyzed through N-ethylmaleimide alkylation,nonreducing electrophoresis.RESULTS:We observed that the cell-proliferation-related phosphoinositide 3-kinase/Akt pathway is activated by HBx in vivo and in vitro.Increased ROS were detected by HBx.Tumor suppressor PTEN,via dephosphorylation of Akt,was oxidized and inactivated by increased ROS.Increased oxidized PTEN activated the mitogenic pathway through over-activated Akt.However,treatment with ROS scavenger N-acetyl cysteine can reverse PTEN to a reduced form.Endogenously produced ROS also stimulated HBx expression.CONCLUSION:HBx induced ROS promoted Akt pathways via oxidized inactive PTEN.HBx and ROS maintained a positive regulatory loop,which aggravated carcinogenesis.展开更多
AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture,...AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture, MTT, Electromicroscopy, agarose gel electrophoresis, lucigenin, Western blot and electrophoretic mobility shift assay (EMSA) analysis were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Lucigenin assay showed the generation of ROS in cells under incubation with JTE-522. The increased ROS generation might contribute to the induction of AGS cells to apoptosis. EMSA and Western blot revealed that NF-kB activity was almost completely inhibited by preventing the degradation of IkBalpha. Additionally, by using Western blot we confirmed that the level of bcl-2 was decreased, whereas p53 showed a great increase following JTE-522 treatment. Their changes were in a dose-dependent manner. CONCLUSION: These findings suggest that reactive oxygen species, NF-kB, p53, bcl-2 and caspase-3 may play an important role in the induction of apoptosis in AGS cells after treatment with JTE-522.展开更多
Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesi...Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesis. ROS participate simultaneously in two signaling pathways that have inverse functions in tumorigenesis, Ras-Raf-MEK1/2-ERK1/2 signaling and the p38 mitogen-activated protein kinases (MAPK) pathway. It is well known that Ras-Raf-MEK1/2-ERK1/2 signaling is related to oncogenesis, while the p38 MAPK pathway contributes to cancer suppression, which involves oncogene-induced senescence, inflammationinduced cellular senescence, replicative senescence, contact inhibition and DNA-damage responses. Thus, ROS may not be an absolute carcinogenic factor or cancer suppressor. The purpose of the present review is to discuss the dual roles of ROS in the pathogenesis of cancer, and the signaling pathway mediating their role in tumorigenesis.展开更多
BACKGROUND The NOD-like receptor family pyrin domain-containing 3(NLRP3)inflammasome is a significant component of the innate immune system that plays a vital role in the development of various parasitic diseases.Howe...BACKGROUND The NOD-like receptor family pyrin domain-containing 3(NLRP3)inflammasome is a significant component of the innate immune system that plays a vital role in the development of various parasitic diseases.However,its role in hepatic alveolar echinococcosis(HAE)remains unclear.AIM To investigate the NLRP3 inflammasome and its mechanism of activation in HAE.METHODS We assessed the expression of NLRP3,caspase-1,interleukin(IL)-1β,and IL-18 in the marginal zone and corresponding normal liver of 60 patients with HAE.A rat model of HAE was employed to investigate the role of the NLRP3 inflammasome in the marginal zone of HAE.Transwell experiments were conducted to investigate the effect of Echinococcus multilocularis(E.multilocularis)in stimulating Kupffer cells and hepatocytes.Furthermore,immunohistochemistry,Western blotting,and enzyme-linked immunosorbent assay were used to evaluate NLRP3,caspase-1,IL-1β,and IL-18 expression;flow cytometry was used to detect apoptosis and reactive oxygen species(ROS).RESULTS NLRP3 inflammasome activation was significantly associated with ROS.Inhibition of ROS production decreased NLRP3-caspase-1-IL-1βpathway activation and mitigated hepatocyte damage and inflammation.CONCLUSION E.multilocularis induces hepatocyte damage and inflammation by activating the ROS-mediated NLRP3-caspase-1-IL-1βpathway in Kupffer cells,indicating that ROS may serve as a potential target for the treatment of HAE.展开更多
Objective To explore the production and cytotoxicity of the reactive oxygen species(ROS)induced by diallyl trisulfid(DATS)in HL-60 cells.Methods HL-60 cells were either treated with various doses of DATS alone,or DATS...Objective To explore the production and cytotoxicity of the reactive oxygen species(ROS)induced by diallyl trisulfid(DATS)in HL-60 cells.Methods HL-60 cells were either treated with various doses of DATS alone,or DATS combination with Apocynin,a specific NADPH oxidase inhibitor,or with antioxidant N-acetyl-L-cysteine(NAC)for 0,1,3,6,12 and 24 hours,respectively.The intracellular ROS level was measured by flow cytometry.The activity of NADPH oxidase was evaluated by NBT reduction experiment.The content of both malondialdehyde(MDA)and the protein carbonyl was analyzed by spectrophotometer.Results The results from flow cytometry indicated that DATS significantly increased the intracellular ROS level in HL-60 cells(P<0.05),which is a dose-and time-dependent.The fluorescence intensities of ROS reached at maximuam when HL-60 cells were incubated with 150 μmol·L-1 DATS for 3 hours.The NBT reduction experiment showed that DATS activated NADPH oxidase which had highest activity when cell were exposed to 150 μmol·L-1 DATS for 3 hours.Results DATS induced MDA and protein carbonyl production in HL-60 cells.Furrthermore,both MDA and protein carbonyl in the cells exposed to 150 μmol·L-1 DATS for 3 hours reached the highest level.Apocynin and NAC could attenuate the production of MDA and protein carbonyl,which suggested that ROS induced by DATS was involved in the toxicity to cells.Conclusions DATS induce ROS production through activating NADPH oxidase in HL-60 cells.ROS induced by DATS increase the oxidation of the membrane lipid and the protein of HL-60 cell.展开更多
OBJECTIVE: To study the molecular mechanism of Buyang Huanwu Tang( 补阳还五汤)(BHT) protecting retinal ganglion cells(RGCs) from oxygen induced oxidative stress and apoptosis after anterior ischemia. METHODS: In this ...OBJECTIVE: To study the molecular mechanism of Buyang Huanwu Tang( 补阳还五汤)(BHT) protecting retinal ganglion cells(RGCs) from oxygen induced oxidative stress and apoptosis after anterior ischemia. METHODS: In this study, the Chinese herbs of BHT were extracted by first boiling in water, then were filtered, concentrated, and freeze-dried. The chemical profile of BHT extract was determined by liquid chromatography mass spectrometry(LC-MS). H2O2-induced RGC-5 cells were used as a cell model to investigate the protective effect and mechanism of BHT on RGCs. RESULTS: The survival rate of damaged RGC-5 by BHT was significantly increased by the 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazolium-romid method. Fluorescence activating cell sorter(FACS analysis) showed that BHT could significantly reduce apoptosis induced by oxidative stress via the reactive oxygen species(ROS)-mitogen-activated protein kinase(MAPK)-Caspase-3 signal pathway. CONCLUSION: BHT possesses a high antioxidant capacity and could significantly reduce ROS levels of RGC-5 cells damaged by H2O2.Therefore, the present study has provided possible alternative strategies for the prevention and treatment of ischemic optic disease by using traditional Chinese herbal formulas.展开更多
AIM:To detect the concentrations of reactive oxygen species(ROS),transient receptor potential mucin-1(TRPML1),and autophagy-related(Atg)proteins(LC3-Ⅰ,LC3-Ⅱ,and Beclin1)in vitreous humor of patients with simple rheg...AIM:To detect the concentrations of reactive oxygen species(ROS),transient receptor potential mucin-1(TRPML1),and autophagy-related(Atg)proteins(LC3-Ⅰ,LC3-Ⅱ,and Beclin1)in vitreous humor of patients with simple rhegmatogenous retinal detachment(RRD).METHODS:RRD patients enrolled as the RRD group,and patients with idiopathic macular hole(IMH)and idiopathic macular epiretinal membrane(IMEM)were enrolled as control group.The levels of ROS,TRPML1,LC3-Ⅰ,LC3-Ⅱ,and Beclin1 in vitreous humor of patients in the RRD and control groups were detected by enzyme-linked immunosorbent assay(ELISA).RESULTS:The RRD group included 28 eyes 28 patients and had a higher concentration of ROS in vitreous humor(631.86±18.05 vs 436.34±108.22 IU/m L,P<0.05).The ROS level in patients with a wide retinal detachment(RD)extent(RD range≥1/2)was higher than that with a narrow RD extent(RD range<1/2,P<0.05).ROS concentration was negatively correlated with RD time(r=-0.46,P=0.01).The expression levels of LC3-Ⅰand Beclin1 significantly decreased in RRD(P<0.05),but there were no correlations with the RD time,RD extent,or macular involvement.CONCLUSION:In eyes with RRD,the concentration of ROS in vitreous humor increases and the expression levels of Atg proteins decrease,reflecting possibly that autophagy is inhibited.展开更多
BACKGROUND Recently,type 2 diabetic osteoporosis(T2DOP)has become a research hotspot for the complications of diabetes,but the specific mechanism of its occurrence and development remains unknown.Ferroptosis caused by...BACKGROUND Recently,type 2 diabetic osteoporosis(T2DOP)has become a research hotspot for the complications of diabetes,but the specific mechanism of its occurrence and development remains unknown.Ferroptosis caused by iron overload is con-sidered an important cause of T2DOP.Polycytosine RNA-binding protein 1(PCBP1),an iron ion chaperone,is considered a protector of ferroptosis.AIM To investigate the existence of ferroptosis and specific role of PCBP1 in the development of type 2 diabetes.METHODS A cell counting kit-8 assay was used to detect changes in osteoblast viability under high glucose(HG)and/or ferroptosis inhibitors at different concentrations and times.Transmission electron microscopy was used to examine the morpho-logical changes in the mitochondria of osteoblasts under HG,and western blotting was used to detect the expression levels of PCBP1,ferritin,and the ferroptosis-related protein glutathione peroxidase 4(GPX4).A lentivirus silenced and overex-pressed PCBP1.Western blotting was used to detect the expression levels of the osteoblast functional proteins osteoprotegerin(OPG)and osteocalcin(OCN),whereas flow cytometry was used to detect changes in reactive oxygen species(ROS)levels in each group.RESULTS Under HG,the viability of osteoblasts was considerably decreased,the number of mitochondria undergoing atrophy was considerably increased,PCBP1 and ferritin expression levels were increased,and GPX4 expression was decreased.Western blotting results demonstrated that infection with lentivirus overexpressing PCBP1,increased the expression levels of ferritin,GPX4,OPG,and OCN,compared with the HG group.Flow cytometry results showed a reduction in ROS,and an opposite result was obtained after silencing PCBP1.CONCLUSION PCBP1 may protect osteoblasts and reduce the harm caused by ferroptosis by promoting ferritin expression under a HG environment.Moreover,PCBP1 may be a potential therapeutic target for T2DOP.展开更多
Renal fibrosis is a common pathway of progressive renal diseases leading to end-stage renal disease regardless of the etiology. Accumulating evidence indicates that oxidative stress, resulting in generation of reactiv...Renal fibrosis is a common pathway of progressive renal diseases leading to end-stage renal disease regardless of the etiology. Accumulating evidence indicates that oxidative stress, resulting in generation of reactive oxygen species (ROS), plays a critical role in the initiation and progression of fibrotic diseases. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is the predominant enzyme source for ROS generation and is now recognized as a key mediator of cell proliferation and matrix accumulation in renal disease. Multiple stimuli and agonists, such as transforming growth factor , tumor necrosis factor, platelet derived growth factor, angiotensin II, hyperglycemia, oxidized low-density lipoprotein and albumin have been shown to alter the activity or expression of the NADPH oxidase and ultimately increase ROS production. ROS directly incites damage to biologically important macromolecules and leads to generation of the so-called advanced oxidation protein products (AOPPs) and advanced glycation end products, which are not only markers of oxidative stress but also cause renal injury. Targeting NADPH oxidase and/or reducing AOPPs production miaht be a novel strateav for the theraoeutic intervention of varietv of fibrotic kidney disorders.展开更多
Chemodynamic therapy(CDT),defined as an in situ oxidative stress response catalyzed by the Fenton or Fenton-like reactions to generate cytotoxic hydroxyl radicals(•OH)at tumor sites,exhibits conspicuous inhibition of ...Chemodynamic therapy(CDT),defined as an in situ oxidative stress response catalyzed by the Fenton or Fenton-like reactions to generate cytotoxic hydroxyl radicals(•OH)at tumor sites,exhibits conspicuous inhibition of tumor growth.It has attracted extensive attention for its outstanding edge in effectiveness,lower systemic toxicity and side effects,sustainability,low cost and convenience.However,the inconfor-mity of harsh Fenton reaction conditions and tumor microenvironment hamper its further development,based on which,numerous researchers have made efforts in further improving the efficiency of CDT.In this review,we expounded antitumor capacity of CDT in mechanism,together with its limitation,and then summarized and came up with several strategies to enhance CDT involved tumor therapy strategies by 1)improving catalytic efficiency;2)increasing hydrogen peroxide levels at tumor sites;3)reducing glutathione levels at tumor sites;4)applying external energy intervention;5)amplifying the distribu-tion of hydroxyl radicals at tumor sites;and 6)combination therapy.Eventually,the perspectives and challenges of CDT are further discussed to encourage more in-depth studies and rational reflections.展开更多
Background Thrombin is a multifunctional serine protease that plays a crucial role in hemostasis following tissue injury.In addition to its procoagulation effect, thrombin is also a potent mesenchymal cell mitogen, th...Background Thrombin is a multifunctional serine protease that plays a crucial role in hemostasis following tissue injury.In addition to its procoagulation effect, thrombin is also a potent mesenchymal cell mitogen, therefore it plays important roles in the local proliferation of mesenchymal cells in the tissue repair process. Reactive oxygen species (ROS) can induce some human cells to proliferate at lower rates while at higher concentrations they promote cells to undergo apoptosis or necrosis. Accumulative evidence suggests that thrombin can induce some cells to produce ROS. Based on these observations, we provide a hypothesis that thrombin can stimulate human lung fibroblasts to produce ROS, which play an important role in human lung fibroblast proliferation.Methods ROS were detected in fibroblasts at 30 minutes and 60 minutes following thrombin (20 U/ml) exposure using flow cytometry. The ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) was assayed in lung fibroblasts using a commercial kit following treatment with thrombin at different concentrations. NADPH oxidase and the extracellular regulated kinase1/2 (ERK1/2) signaling pathway were detected by Western blotting after thrombin stimulation to lung fibroblasts.Results Thrombin, at 20 U/ml, stimulated human lung fibroblasts (HLF) to generate ROS in a time dependent manner.The ratio of GSH/GSSG in fibroblasts treated with thrombin showed a significant decrease. NADPH oxidase was activated and the ERK1/2 signal pathway was involved in the proliferation process of fibroblasts treated with thrombin.Conclusion The activation of NADPH oxidase by thrombin leads to the production of ROS, which promotes fibroblasts proliferation via activation of the ERK1/2 signaling pathway.展开更多
Reactive oxygen species(ROS) are free radicals thought to mediate the neurotoxic effects of several neurodegenerative disorders.In the central nervous system,ROS can also trigger a phenotypic switch in both astrocyt...Reactive oxygen species(ROS) are free radicals thought to mediate the neurotoxic effects of several neurodegenerative disorders.In the central nervous system,ROS can also trigger a phenotypic switch in both astrocytes and microglia that further aggravates neurodegeneration,termed reactive gliosis.Negative regulators of ROS,such as mitochondrial uncoupling protein 2(UCP2) are neuroprotective factors that decrease neuron loss in models of stroke,epilepsy,and parkinsonism.However,it is unclear whether UCP2 acts purely to prevent ROS production,or also to prevent gliosis.In this review article,we discuss published evidence supporting the hypothesis that UCP2 is a neuroprotective factor both through its direct effects in decreasing mitochondrial ROS and through its effects in astrocytes and microglia.A major effect of UCP2 activation in glia is a change in the spectrum of secreted cytokines towards a more anti-inflammatory spectrum.There are multiple mechanisms that can control the level or activity of UCP2,including a variety of metabolites and micro RNAs.Understanding these mechanisms will be key to exploitingthe protective effects of UCP2 in therapies for multiple neurodegenerative conditions.展开更多
BACKGROUND:Paraquat(PQ)-induced acute lung injury(ALI)and pulmonary fi brosis are common diseases with high mortality but without eff ective antidotes in emergency medicine.Our previous study has proved that arctigeni...BACKGROUND:Paraquat(PQ)-induced acute lung injury(ALI)and pulmonary fi brosis are common diseases with high mortality but without eff ective antidotes in emergency medicine.Our previous study has proved that arctigenin suppressed pulmonary fibrosis induced by PQ.We wondered whether arctigenin could also have a protective eff ect on PQ-induced ALI.METHODS:A PQ-induced A549 cell injury model was used,and the effect of arctigenin was determined by a cell counting kit-8(CCK-8)cell viability assay.In addition,terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick-end labelling(TUNEL)staining assays and mitochondrial membrane potential assays were performed to evaluate the level of cell apoptosis.The generation of reactive oxygen species(ROS)was refl ected by dihydroethidium(DHE)staining and a 2’,7’-dichlorodihy drofluorescein diacetate(DCFH-DA)assay.Moreover,immunoblotting studies were used to assess the expression of mitogen-activated protein kinases(MAPKs)and p38 MAPK.RESULTS:Arctigenin attenuated PQ-induced inhibition of A549 cell viability in a dose-dependent manner.Arctigenin also significantly reduced PQ-induced A549 cell apoptosis,as refl ected by the TUNEL assay and mitochondrial membrane potential assay,which may result from suppressed ROS/p38 MAPK signaling because we found that arctigenin dramatically suppressed ROS generation and p38 MAPK phosphorylation.CONCLUSION:Arctigenin could attenuate PQ-induced lung epithelial A549 cell injury in vitro by suppressing ROS/p38 MAPK-mediated cell apoptosis,and arctigenin might be considered a potential candidate drug for PQ-induced ALI.展开更多
To investigate whether single nucleotide polymorphisms in maf protein K (MAFK), which encodes the MAFK, lead to increased susceptibility to ulcerative colitis in the Japanese population. METHODSThis case control study...To investigate whether single nucleotide polymorphisms in maf protein K (MAFK), which encodes the MAFK, lead to increased susceptibility to ulcerative colitis in the Japanese population. METHODSThis case control study examined the associations between MAFK single nucleotide polymorphisms (rs4268033 G>A, rs3735656 T>C and rs10226620 C>T) and ulcerative colitis susceptibility in 174 patients with ulcerative colitis (UC) cases, and 748 subjects without no lower abdominal symptoms, diarrhea or hematochezia (controls). In addition, as the second controls, we set 360 subjects, who have an irregular bowel movement without abnormal lower endoscopic findings (IBM controls). RESULTSThe genotype frequency of rs4268033 AA and allelic frequency of the rs4268033A allele were significantly higher in the UC cases than in both controls (P = 0.0005 and < 0.0001, P = 0.015 and 0.0027 vs controls and IBM controls, respectively). Logistic regression analysis after adjustment for age and gender showed that the rs4268033 AA and rs3735656 CC genotypes were significantly associated with susceptibility to UC development (OR = 2.63, 95%CI: 1.61-4.30, P = 0.0001 and OR = 1.81; 95%CI: 1.12-2.94, P = 0.015, respectively). Similar findings were observed by the comparison with IBM controls. In addition, the rs4268033 AA genotype was significantly associated with all phenotypes of UC except early onset. There was no significant association between rs10226620 and ulcerative colitis. CONCLUSIONOur results provide the first evidence that MAFK genetic polymorphisms are significantly associated with susceptibility to UC development. In particular, rs4268033 is closely associated with an increased risk for the development of UC.展开更多
We previously found that oxygen-glucose-serum deprivation/restoration(OGSD/R) induces apoptosis of spinal cord astrocytes, possibly via caspase-12 and the integrated stress response, which involves protein kinase R-...We previously found that oxygen-glucose-serum deprivation/restoration(OGSD/R) induces apoptosis of spinal cord astrocytes, possibly via caspase-12 and the integrated stress response, which involves protein kinase R-like endoplasmic reticulum kinase(PERK), eukaryotic initiation factor 2-alpha(eIF2α) and activating transcription factor 4(ATF4). We hypothesized that edaravone, a low molecular weight, lipophilic free radical scavenger, would reduce OGSD/R-induced apoptosis of spinal cord astrocytes. To test this, we established primary cultures of rat astrocytes, and exposed them to 8 hours/6 hours of OGSD/R with or without edaravone(0.1, 1, 10, 100 μM) treatment. We found that 100 μM of edaravone significantly suppressed astrocyte apoptosis and inhibited the release of reactive oxygen species. It also inhibited the activation of caspase-12 and caspase-3, and reduced the expression of homologous CCAAT/enhancer binding protein, phosphorylated(p)-PERK, p-eIF2α, and ATF4. These results point to a new use of an established drug in the prevention of OGSD/R-mediated spinal cord astrocyte apoptosis via the integrated stress response.展开更多
Salinity is a serious challenge for agriculture production by limiting the arable land.Rice is a major staple food crop but very sensitive to salt stress.In this study,we used Arabidopsis for the functional characteri...Salinity is a serious challenge for agriculture production by limiting the arable land.Rice is a major staple food crop but very sensitive to salt stress.In this study,we used Arabidopsis for the functional characterization of a rice F-box gene LOC_Os04g48270(OsPP12-A13)under salinity stress.OsPP12-A13 is a nuclear-localized protein that is strongly upregulated under salinity stress in rice and showed the highest expression in the stem,followed by roots and leaves.Two types of transgenic lines for OsPP12-A13 were generated,including constitutive tissue over-expression using the CaMV35S promoter and phloem specific over-expression using the pSUC2 promoter.Both types of transgenic plants showed salinity tolerance at the seedling stage through higher germination percentage and longer root length,as compared to control plants under salt stress in MS medium.Both the transgenic plants also exhibited salt tolerance at the reproductive stage through higher survival rate,plant dry biomass,and seed yield per plant as compared to control plants.Determination of Na+concentration in leaves,stem and roots of salt-stressed transgenic plants showed that Na^(+) concentration was less in leaf and stem as compared to roots.The opposite was observed in wild type stressed plants,suggesting that OsPP12-A13 may be involved in Na+transport from root to leaf.Transgenic plants also displayed less ROS levels and higher activities of peroxidase and glutathione S-transferase along with upregulation of their corresponding genes as compared to control plants which further indicated a role of OsPP12-A13 in maintaining ROS homeostasis under salt stress.Further,the non-significant difference between the transgenic lines obtained from the two vectors highlighted that OsPP12-A13 principally works in the phloem.Taken together,this study showed that OsPP12-A13 improves salt tolerance in rice,possibly by affecting Na^(+) transport and ROS homeostasis.展开更多
文摘BACKGROUND: Brief exposure to the anesthetic sevoflurane results in delayed neuroprotection, However, few studies have addressed delayed neuroprotection after preconditioning with a single administration of sevoflurane. OBJECTIVE: To explore the relationship between a single preconditioning administration of sevoflurane and reactive oxygen species production and protein kinase C-epsilon (PKC-ε ) translocation. DESIGN, TIME, AND SETTING: The randomized, controlled, animal experiment was conducted at the Central Laboratory, Xiangya Hospital, Central South University, China from November 2007 to April 2008. MATERIALS: A total of 120 healthy, male, Sprague Dawley rats were equally and randomly assigned into five groups: sham operation, ischemia/reperfusion, sevoflurane, 2-mercaptopropionylglycine (2-MPG, a selective reactive oxygen species scavenger) + sevoflurane (MPG + sevoflurane), and MPG. Sevoflurane (Baxter, USA) and MPG (Sigma, USA) were used in this study. METHODS: Intervention consisted of three procedures. (1) MPG injection: a selective reactive oxygen species scavenger, MPG (20 mg/kg), was infused into the rat caudal vein in the MPG and MPG + sevoflurane groups. (2) Sevoflurane preconditioning: 30 minutes following MPG injection, rats in the sevoflurane and MPG + sevoflurane groups breathed a mixed gas of 2.4% sevoflurane and 97.6% oxygen for 60 minutes. Rats in the sham operation, ischemia/reperfusion, and MPG groups breathed 100% pure oxygen for 60 minutes. (3) IschemiaJreperfusion: 24 hours after sevoflurane or pure oxygen preconditioning, middle cerebral artery occlusion models were established in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups. Following 2 hours ischemia/6 hours and 24 hours reperfusion, the carotid artery was separated, but the middle cerebral artery was not occluded, in the sham operation group. MAIN OUTCOME MEASURES: In the ischemic hemisphere, PKC-ε translocation in the rat parietal cortex was measured by Western blot analysis. Infarct volume was calculated using the TTC assay. Neurological deficits were evaluated in rats using a scoring system of 8 points. RESULTS: After 6 hours reperfusion, the ratio of PKC-ε in membrane/(cytosol + membrane) was significantly less in the sham operation group than in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane), and MPG groups (P 〈 0.05). The ratio of PKC-ε in membrane/(cytosol + membrane) was significantly greater in the sevoflurane group than in the sham operation, ischemia/reperfusion, MPG + sevoflurane, and MPG groups (P 〈 0.05). No significant differences were observed in the ischemiaJreperfusJon, M PG + sevoflurane, and MPG groups (P 〉 0.05). Following 24 hours reperfusion, the ratio of PKC-ε in membrane/(cytosol + membrane) was significantly less in the sham operation group than in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups (P 〈 0.05). No significant differences were detected in the ischemia/reperfusion, sevoflurane, MPG + sevoflurane, and MPG groups (P 〉 0.05). Compared with the ischemia/reperfusion, MPG + sevoflurane, and MPG groups, infarct volume was significantly smaller, and neurological deficits were significantly improved, in the sevoflurane group (P 〈 0.05). No significant differences in infarct volume and neurological deficits were observed among the ischemia/reperfusion, MPG + sevoflurane, and MPG groups (P 〉 0.05). Infarcts or neurological deficits were not detected in the sham operation group. CONCLUSION: A single preconditioning administration of sevoflurane reduced infarct volumes and improved neurological deficits in ischemic rats. Delayed neuroprotection may be mediated by reactive oxygen species and correlated to PKC- ε activation.
文摘BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC.
基金Supported by The 21st century Frontier Program in the Functional Human Genome Project,No.HGM0200934the International Collaboration Program of Science and Technology,No. FGM0600914+1 种基金the Research Program for New Drug Target Discovery Grant from the Ministry of Education,Science & Technology,No.NBM3300711the KRIBB Research Initiative Program Grant,No.KGM3320911
文摘AIM:To investigate the role of hepatitis B virus X-protein(HBx)-induced reactive oxygen species(ROS)on liver carcinogenesis in HBx transgenic mice and HepG2-HBx cells.METHODS:Cell growth rate was analyzed,and through western blotting,mitogenic signaling was observed.Endogenous ROS from wild and HBx transgenic mice and HepG2-Mock and HBx cells were assayed by FACS-calibur.Identification of oxidized and reduced phosphatase and tensin homolog(PTEN)was analyzed through N-ethylmaleimide alkylation,nonreducing electrophoresis.RESULTS:We observed that the cell-proliferation-related phosphoinositide 3-kinase/Akt pathway is activated by HBx in vivo and in vitro.Increased ROS were detected by HBx.Tumor suppressor PTEN,via dephosphorylation of Akt,was oxidized and inactivated by increased ROS.Increased oxidized PTEN activated the mitogenic pathway through over-activated Akt.However,treatment with ROS scavenger N-acetyl cysteine can reverse PTEN to a reduced form.Endogenously produced ROS also stimulated HBx expression.CONCLUSION:HBx induced ROS promoted Akt pathways via oxidized inactive PTEN.HBx and ROS maintained a positive regulatory loop,which aggravated carcinogenesis.
基金National Natural Science Foundation of China,No.39770300,30070873the Overseas Chinese Affairs Office of the State Council Foundation,No.98-33
文摘AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture, MTT, Electromicroscopy, agarose gel electrophoresis, lucigenin, Western blot and electrophoretic mobility shift assay (EMSA) analysis were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Lucigenin assay showed the generation of ROS in cells under incubation with JTE-522. The increased ROS generation might contribute to the induction of AGS cells to apoptosis. EMSA and Western blot revealed that NF-kB activity was almost completely inhibited by preventing the degradation of IkBalpha. Additionally, by using Western blot we confirmed that the level of bcl-2 was decreased, whereas p53 showed a great increase following JTE-522 treatment. Their changes were in a dose-dependent manner. CONCLUSION: These findings suggest that reactive oxygen species, NF-kB, p53, bcl-2 and caspase-3 may play an important role in the induction of apoptosis in AGS cells after treatment with JTE-522.
基金Supported by National Natural Science Foundation of China, No. 30750013 Key Science Research Project Natural Science Foundation of Xiamen, No. WKZ0501
文摘Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesis. ROS participate simultaneously in two signaling pathways that have inverse functions in tumorigenesis, Ras-Raf-MEK1/2-ERK1/2 signaling and the p38 mitogen-activated protein kinases (MAPK) pathway. It is well known that Ras-Raf-MEK1/2-ERK1/2 signaling is related to oncogenesis, while the p38 MAPK pathway contributes to cancer suppression, which involves oncogene-induced senescence, inflammationinduced cellular senescence, replicative senescence, contact inhibition and DNA-damage responses. Thus, ROS may not be an absolute carcinogenic factor or cancer suppressor. The purpose of the present review is to discuss the dual roles of ROS in the pathogenesis of cancer, and the signaling pathway mediating their role in tumorigenesis.
基金Supported by the National Major Research and Development Project of“Precision Medicine Research”,No.2017YFC0909900Qinghai Province Science and Technology Department Programme,No.2019-SF-131the Qinghai Province Health and Family Planning Commission Programme,No.2016-wjzd-04.
文摘BACKGROUND The NOD-like receptor family pyrin domain-containing 3(NLRP3)inflammasome is a significant component of the innate immune system that plays a vital role in the development of various parasitic diseases.However,its role in hepatic alveolar echinococcosis(HAE)remains unclear.AIM To investigate the NLRP3 inflammasome and its mechanism of activation in HAE.METHODS We assessed the expression of NLRP3,caspase-1,interleukin(IL)-1β,and IL-18 in the marginal zone and corresponding normal liver of 60 patients with HAE.A rat model of HAE was employed to investigate the role of the NLRP3 inflammasome in the marginal zone of HAE.Transwell experiments were conducted to investigate the effect of Echinococcus multilocularis(E.multilocularis)in stimulating Kupffer cells and hepatocytes.Furthermore,immunohistochemistry,Western blotting,and enzyme-linked immunosorbent assay were used to evaluate NLRP3,caspase-1,IL-1β,and IL-18 expression;flow cytometry was used to detect apoptosis and reactive oxygen species(ROS).RESULTS NLRP3 inflammasome activation was significantly associated with ROS.Inhibition of ROS production decreased NLRP3-caspase-1-IL-1βpathway activation and mitigated hepatocyte damage and inflammation.CONCLUSION E.multilocularis induces hepatocyte damage and inflammation by activating the ROS-mediated NLRP3-caspase-1-IL-1βpathway in Kupffer cells,indicating that ROS may serve as a potential target for the treatment of HAE.
文摘Objective To explore the production and cytotoxicity of the reactive oxygen species(ROS)induced by diallyl trisulfid(DATS)in HL-60 cells.Methods HL-60 cells were either treated with various doses of DATS alone,or DATS combination with Apocynin,a specific NADPH oxidase inhibitor,or with antioxidant N-acetyl-L-cysteine(NAC)for 0,1,3,6,12 and 24 hours,respectively.The intracellular ROS level was measured by flow cytometry.The activity of NADPH oxidase was evaluated by NBT reduction experiment.The content of both malondialdehyde(MDA)and the protein carbonyl was analyzed by spectrophotometer.Results The results from flow cytometry indicated that DATS significantly increased the intracellular ROS level in HL-60 cells(P<0.05),which is a dose-and time-dependent.The fluorescence intensities of ROS reached at maximuam when HL-60 cells were incubated with 150 μmol·L-1 DATS for 3 hours.The NBT reduction experiment showed that DATS activated NADPH oxidase which had highest activity when cell were exposed to 150 μmol·L-1 DATS for 3 hours.Results DATS induced MDA and protein carbonyl production in HL-60 cells.Furrthermore,both MDA and protein carbonyl in the cells exposed to 150 μmol·L-1 DATS for 3 hours reached the highest level.Apocynin and NAC could attenuate the production of MDA and protein carbonyl,which suggested that ROS induced by DATS was involved in the toxicity to cells.Conclusions DATS induce ROS production through activating NADPH oxidase in HL-60 cells.ROS induced by DATS increase the oxidation of the membrane lipid and the protein of HL-60 cell.
基金Supported by China Postdoctoral Science Foundation (Experimental Study on the Inhibitory Effect of Yiqi Tongluo Method on RGCs Apoptosis in AION Model Rats, No. 2017M621180)。
文摘OBJECTIVE: To study the molecular mechanism of Buyang Huanwu Tang( 补阳还五汤)(BHT) protecting retinal ganglion cells(RGCs) from oxygen induced oxidative stress and apoptosis after anterior ischemia. METHODS: In this study, the Chinese herbs of BHT were extracted by first boiling in water, then were filtered, concentrated, and freeze-dried. The chemical profile of BHT extract was determined by liquid chromatography mass spectrometry(LC-MS). H2O2-induced RGC-5 cells were used as a cell model to investigate the protective effect and mechanism of BHT on RGCs. RESULTS: The survival rate of damaged RGC-5 by BHT was significantly increased by the 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazolium-romid method. Fluorescence activating cell sorter(FACS analysis) showed that BHT could significantly reduce apoptosis induced by oxidative stress via the reactive oxygen species(ROS)-mitogen-activated protein kinase(MAPK)-Caspase-3 signal pathway. CONCLUSION: BHT possesses a high antioxidant capacity and could significantly reduce ROS levels of RGC-5 cells damaged by H2O2.Therefore, the present study has provided possible alternative strategies for the prevention and treatment of ischemic optic disease by using traditional Chinese herbal formulas.
基金Supported by the National Natural Science Foundation of China(No.82070977)。
文摘AIM:To detect the concentrations of reactive oxygen species(ROS),transient receptor potential mucin-1(TRPML1),and autophagy-related(Atg)proteins(LC3-Ⅰ,LC3-Ⅱ,and Beclin1)in vitreous humor of patients with simple rhegmatogenous retinal detachment(RRD).METHODS:RRD patients enrolled as the RRD group,and patients with idiopathic macular hole(IMH)and idiopathic macular epiretinal membrane(IMEM)were enrolled as control group.The levels of ROS,TRPML1,LC3-Ⅰ,LC3-Ⅱ,and Beclin1 in vitreous humor of patients in the RRD and control groups were detected by enzyme-linked immunosorbent assay(ELISA).RESULTS:The RRD group included 28 eyes 28 patients and had a higher concentration of ROS in vitreous humor(631.86±18.05 vs 436.34±108.22 IU/m L,P<0.05).The ROS level in patients with a wide retinal detachment(RD)extent(RD range≥1/2)was higher than that with a narrow RD extent(RD range<1/2,P<0.05).ROS concentration was negatively correlated with RD time(r=-0.46,P=0.01).The expression levels of LC3-Ⅰand Beclin1 significantly decreased in RRD(P<0.05),but there were no correlations with the RD time,RD extent,or macular involvement.CONCLUSION:In eyes with RRD,the concentration of ROS in vitreous humor increases and the expression levels of Atg proteins decrease,reflecting possibly that autophagy is inhibited.
基金Supported by the National Natural Science Foundation of China,No.81471094 and No.82202743.
文摘BACKGROUND Recently,type 2 diabetic osteoporosis(T2DOP)has become a research hotspot for the complications of diabetes,but the specific mechanism of its occurrence and development remains unknown.Ferroptosis caused by iron overload is con-sidered an important cause of T2DOP.Polycytosine RNA-binding protein 1(PCBP1),an iron ion chaperone,is considered a protector of ferroptosis.AIM To investigate the existence of ferroptosis and specific role of PCBP1 in the development of type 2 diabetes.METHODS A cell counting kit-8 assay was used to detect changes in osteoblast viability under high glucose(HG)and/or ferroptosis inhibitors at different concentrations and times.Transmission electron microscopy was used to examine the morpho-logical changes in the mitochondria of osteoblasts under HG,and western blotting was used to detect the expression levels of PCBP1,ferritin,and the ferroptosis-related protein glutathione peroxidase 4(GPX4).A lentivirus silenced and overex-pressed PCBP1.Western blotting was used to detect the expression levels of the osteoblast functional proteins osteoprotegerin(OPG)and osteocalcin(OCN),whereas flow cytometry was used to detect changes in reactive oxygen species(ROS)levels in each group.RESULTS Under HG,the viability of osteoblasts was considerably decreased,the number of mitochondria undergoing atrophy was considerably increased,PCBP1 and ferritin expression levels were increased,and GPX4 expression was decreased.Western blotting results demonstrated that infection with lentivirus overexpressing PCBP1,increased the expression levels of ferritin,GPX4,OPG,and OCN,compared with the HG group.Flow cytometry results showed a reduction in ROS,and an opposite result was obtained after silencing PCBP1.CONCLUSION PCBP1 may protect osteoblasts and reduce the harm caused by ferroptosis by promoting ferritin expression under a HG environment.Moreover,PCBP1 may be a potential therapeutic target for T2DOP.
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 30830056 and No. U0932002). Conflict of interests: None.
文摘Renal fibrosis is a common pathway of progressive renal diseases leading to end-stage renal disease regardless of the etiology. Accumulating evidence indicates that oxidative stress, resulting in generation of reactive oxygen species (ROS), plays a critical role in the initiation and progression of fibrotic diseases. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is the predominant enzyme source for ROS generation and is now recognized as a key mediator of cell proliferation and matrix accumulation in renal disease. Multiple stimuli and agonists, such as transforming growth factor , tumor necrosis factor, platelet derived growth factor, angiotensin II, hyperglycemia, oxidized low-density lipoprotein and albumin have been shown to alter the activity or expression of the NADPH oxidase and ultimately increase ROS production. ROS directly incites damage to biologically important macromolecules and leads to generation of the so-called advanced oxidation protein products (AOPPs) and advanced glycation end products, which are not only markers of oxidative stress but also cause renal injury. Targeting NADPH oxidase and/or reducing AOPPs production miaht be a novel strateav for the theraoeutic intervention of varietv of fibrotic kidney disorders.
基金supported by the National Natural Science Foundation of China(No.81822025)1.3.5 Project for Disciplines of Excellence,West China Hospital,Sichuan University(No.ZYYC08002).
文摘Chemodynamic therapy(CDT),defined as an in situ oxidative stress response catalyzed by the Fenton or Fenton-like reactions to generate cytotoxic hydroxyl radicals(•OH)at tumor sites,exhibits conspicuous inhibition of tumor growth.It has attracted extensive attention for its outstanding edge in effectiveness,lower systemic toxicity and side effects,sustainability,low cost and convenience.However,the inconfor-mity of harsh Fenton reaction conditions and tumor microenvironment hamper its further development,based on which,numerous researchers have made efforts in further improving the efficiency of CDT.In this review,we expounded antitumor capacity of CDT in mechanism,together with its limitation,and then summarized and came up with several strategies to enhance CDT involved tumor therapy strategies by 1)improving catalytic efficiency;2)increasing hydrogen peroxide levels at tumor sites;3)reducing glutathione levels at tumor sites;4)applying external energy intervention;5)amplifying the distribu-tion of hydroxyl radicals at tumor sites;and 6)combination therapy.Eventually,the perspectives and challenges of CDT are further discussed to encourage more in-depth studies and rational reflections.
文摘Background Thrombin is a multifunctional serine protease that plays a crucial role in hemostasis following tissue injury.In addition to its procoagulation effect, thrombin is also a potent mesenchymal cell mitogen, therefore it plays important roles in the local proliferation of mesenchymal cells in the tissue repair process. Reactive oxygen species (ROS) can induce some human cells to proliferate at lower rates while at higher concentrations they promote cells to undergo apoptosis or necrosis. Accumulative evidence suggests that thrombin can induce some cells to produce ROS. Based on these observations, we provide a hypothesis that thrombin can stimulate human lung fibroblasts to produce ROS, which play an important role in human lung fibroblast proliferation.Methods ROS were detected in fibroblasts at 30 minutes and 60 minutes following thrombin (20 U/ml) exposure using flow cytometry. The ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) was assayed in lung fibroblasts using a commercial kit following treatment with thrombin at different concentrations. NADPH oxidase and the extracellular regulated kinase1/2 (ERK1/2) signaling pathway were detected by Western blotting after thrombin stimulation to lung fibroblasts.Results Thrombin, at 20 U/ml, stimulated human lung fibroblasts (HLF) to generate ROS in a time dependent manner.The ratio of GSH/GSSG in fibroblasts treated with thrombin showed a significant decrease. NADPH oxidase was activated and the ERK1/2 signal pathway was involved in the proliferation process of fibroblasts treated with thrombin.Conclusion The activation of NADPH oxidase by thrombin leads to the production of ROS, which promotes fibroblasts proliferation via activation of the ERK1/2 signaling pathway.
文摘Reactive oxygen species(ROS) are free radicals thought to mediate the neurotoxic effects of several neurodegenerative disorders.In the central nervous system,ROS can also trigger a phenotypic switch in both astrocytes and microglia that further aggravates neurodegeneration,termed reactive gliosis.Negative regulators of ROS,such as mitochondrial uncoupling protein 2(UCP2) are neuroprotective factors that decrease neuron loss in models of stroke,epilepsy,and parkinsonism.However,it is unclear whether UCP2 acts purely to prevent ROS production,or also to prevent gliosis.In this review article,we discuss published evidence supporting the hypothesis that UCP2 is a neuroprotective factor both through its direct effects in decreasing mitochondrial ROS and through its effects in astrocytes and microglia.A major effect of UCP2 activation in glia is a change in the spectrum of secreted cytokines towards a more anti-inflammatory spectrum.There are multiple mechanisms that can control the level or activity of UCP2,including a variety of metabolites and micro RNAs.Understanding these mechanisms will be key to exploitingthe protective effects of UCP2 in therapies for multiple neurodegenerative conditions.
基金This work was supported by the National Natural Science Foundation of China(82172182 and 82102311)Social Development Projects of Jiangsu Province(BE2017720)+2 种基金Natural Science Foundation of Jiangsu Province(BK20190247)Science Foundation of Jiangsu Health Commission(H2018039)Jiangsu Postdoctoral Research Foundation(2018K048A and 2020Z193).
文摘BACKGROUND:Paraquat(PQ)-induced acute lung injury(ALI)and pulmonary fi brosis are common diseases with high mortality but without eff ective antidotes in emergency medicine.Our previous study has proved that arctigenin suppressed pulmonary fibrosis induced by PQ.We wondered whether arctigenin could also have a protective eff ect on PQ-induced ALI.METHODS:A PQ-induced A549 cell injury model was used,and the effect of arctigenin was determined by a cell counting kit-8(CCK-8)cell viability assay.In addition,terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick-end labelling(TUNEL)staining assays and mitochondrial membrane potential assays were performed to evaluate the level of cell apoptosis.The generation of reactive oxygen species(ROS)was refl ected by dihydroethidium(DHE)staining and a 2’,7’-dichlorodihy drofluorescein diacetate(DCFH-DA)assay.Moreover,immunoblotting studies were used to assess the expression of mitogen-activated protein kinases(MAPKs)and p38 MAPK.RESULTS:Arctigenin attenuated PQ-induced inhibition of A549 cell viability in a dose-dependent manner.Arctigenin also significantly reduced PQ-induced A549 cell apoptosis,as refl ected by the TUNEL assay and mitochondrial membrane potential assay,which may result from suppressed ROS/p38 MAPK signaling because we found that arctigenin dramatically suppressed ROS generation and p38 MAPK phosphorylation.CONCLUSION:Arctigenin could attenuate PQ-induced lung epithelial A549 cell injury in vitro by suppressing ROS/p38 MAPK-mediated cell apoptosis,and arctigenin might be considered a potential candidate drug for PQ-induced ALI.
文摘To investigate whether single nucleotide polymorphisms in maf protein K (MAFK), which encodes the MAFK, lead to increased susceptibility to ulcerative colitis in the Japanese population. METHODSThis case control study examined the associations between MAFK single nucleotide polymorphisms (rs4268033 G>A, rs3735656 T>C and rs10226620 C>T) and ulcerative colitis susceptibility in 174 patients with ulcerative colitis (UC) cases, and 748 subjects without no lower abdominal symptoms, diarrhea or hematochezia (controls). In addition, as the second controls, we set 360 subjects, who have an irregular bowel movement without abnormal lower endoscopic findings (IBM controls). RESULTSThe genotype frequency of rs4268033 AA and allelic frequency of the rs4268033A allele were significantly higher in the UC cases than in both controls (P = 0.0005 and < 0.0001, P = 0.015 and 0.0027 vs controls and IBM controls, respectively). Logistic regression analysis after adjustment for age and gender showed that the rs4268033 AA and rs3735656 CC genotypes were significantly associated with susceptibility to UC development (OR = 2.63, 95%CI: 1.61-4.30, P = 0.0001 and OR = 1.81; 95%CI: 1.12-2.94, P = 0.015, respectively). Similar findings were observed by the comparison with IBM controls. In addition, the rs4268033 AA genotype was significantly associated with all phenotypes of UC except early onset. There was no significant association between rs10226620 and ulcerative colitis. CONCLUSIONOur results provide the first evidence that MAFK genetic polymorphisms are significantly associated with susceptibility to UC development. In particular, rs4268033 is closely associated with an increased risk for the development of UC.
基金supported by a grant from the Science&Technology Bureau of Changzhou City of China,No.CJ20130029
文摘We previously found that oxygen-glucose-serum deprivation/restoration(OGSD/R) induces apoptosis of spinal cord astrocytes, possibly via caspase-12 and the integrated stress response, which involves protein kinase R-like endoplasmic reticulum kinase(PERK), eukaryotic initiation factor 2-alpha(eIF2α) and activating transcription factor 4(ATF4). We hypothesized that edaravone, a low molecular weight, lipophilic free radical scavenger, would reduce OGSD/R-induced apoptosis of spinal cord astrocytes. To test this, we established primary cultures of rat astrocytes, and exposed them to 8 hours/6 hours of OGSD/R with or without edaravone(0.1, 1, 10, 100 μM) treatment. We found that 100 μM of edaravone significantly suppressed astrocyte apoptosis and inhibited the release of reactive oxygen species. It also inhibited the activation of caspase-12 and caspase-3, and reduced the expression of homologous CCAAT/enhancer binding protein, phosphorylated(p)-PERK, p-eIF2α, and ATF4. These results point to a new use of an established drug in the prevention of OGSD/R-mediated spinal cord astrocyte apoptosis via the integrated stress response.
基金supported by the Crop Breeding Special Project(XZ201901NB03)the Identification of experimental planting and ecological adaptability of rice in high-altitude areas of Tibet(XZ-2019-NK-NS-0010)。
文摘Salinity is a serious challenge for agriculture production by limiting the arable land.Rice is a major staple food crop but very sensitive to salt stress.In this study,we used Arabidopsis for the functional characterization of a rice F-box gene LOC_Os04g48270(OsPP12-A13)under salinity stress.OsPP12-A13 is a nuclear-localized protein that is strongly upregulated under salinity stress in rice and showed the highest expression in the stem,followed by roots and leaves.Two types of transgenic lines for OsPP12-A13 were generated,including constitutive tissue over-expression using the CaMV35S promoter and phloem specific over-expression using the pSUC2 promoter.Both types of transgenic plants showed salinity tolerance at the seedling stage through higher germination percentage and longer root length,as compared to control plants under salt stress in MS medium.Both the transgenic plants also exhibited salt tolerance at the reproductive stage through higher survival rate,plant dry biomass,and seed yield per plant as compared to control plants.Determination of Na+concentration in leaves,stem and roots of salt-stressed transgenic plants showed that Na^(+) concentration was less in leaf and stem as compared to roots.The opposite was observed in wild type stressed plants,suggesting that OsPP12-A13 may be involved in Na+transport from root to leaf.Transgenic plants also displayed less ROS levels and higher activities of peroxidase and glutathione S-transferase along with upregulation of their corresponding genes as compared to control plants which further indicated a role of OsPP12-A13 in maintaining ROS homeostasis under salt stress.Further,the non-significant difference between the transgenic lines obtained from the two vectors highlighted that OsPP12-A13 principally works in the phloem.Taken together,this study showed that OsPP12-A13 improves salt tolerance in rice,possibly by affecting Na^(+) transport and ROS homeostasis.