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1.
AIM: To investigate the effects of Schisandrin B (Sch B) on apoptosis of lens epithelial cells (LEC) treated with H2O2. METHODS: Eyes in SDrats were excised and lenses were separated under operating microscope in sterilized condition. Lenses were divided randomly into four groups with different treatment: control group, hydrogen peroxide group (H2O2), pirenoxine sodium group (PS) and schisandrin Bgroup (Sch B). Lenses were incubated in CO2 incubator for 24 h with 300 μmol·L-1 H2O2 and with or without 0.5 mmol·L-1 Sch B. LECaoptosis and apoptosis rate were measured by TUNELmethod. Ultrastructure changes and apoptosis bodies of LECwere observed via transmitted electron microscope. RESULTS: (1) Apoptosis rate in H2O2 group (92.0±2.6) was significantly higher than that in control group (3.5±1.8). Apoptosis rate in Sch Bgroup (13.8±3.27) was remarkably lower than that in H2O2 group and PSgroup. (2) Ultrastructure observation indicated that apoptosis cells occurred in most LEC in H2O2 group and the changes were severe presenting different stages. While a few apoptosis cells were observed in Sch Bgroup, the changes were slight and most of them were in early and middle stages. CONCLUSION: These data indicated that Sch Bsignificantly inhibited apoptosis of LECduring experimental oxidative injury, the effects were stronger than PS.  相似文献   

2.
AIM and METHODS: The effects of hydrogen peroxide on Na+ currents were studied in freshly dissociated rat hippocampal CA1 neurons using the whole-cell patch-clamp techinique. RESULTS: ①H2O2 caused a dose-dependent and voltage-dependent increase in the voltage-activated Na+ currents. The amplitudes of Na+ currents were increased (48.0±4.2)% and (88. 2±5. 1)% (n=10) by H2O2 at 10 μmol/L and 100 μmol/L, respectively. ②H2O2 (10 μmol/L) did not affect the activation process, but changed the inactivation process significantly. Before and after application of 10 μmol/L of H2O2, the half-inactivation voltage was (-64.58±1.22)mV and (-53.55±0.94)mV (n=10, P<0.01), but the slope factor was not changed. CONCLUSION: As a product of oxidation metabolism, H2O2 is related to some diseases in the central nervous system.  相似文献   

3.
AIM: To study the role and regulation of calcineurin(CaN) in angiotensin II(AngⅡ)-stimulated cardiacmyocyte hypertrophy of rats. METHODS: Using AngⅡ to induce the cultured cardiac myocyte hypertrophy of rats, and investigating the effect of CaN inhibitor on [3H]-leucine incorporation of AngⅡ-stimulated cardiomyocytes and the regulation of various factors on CaN activity in cardiomyocytes.RESULTS: AngⅡ can stimulate the CaN activity in cultured neonatal rat cardiomyocytes in a dose- and time-dependent manner. In cardiac myocytes incubated with 10, 100, 1000 nmol·L-1 of AngⅡ for 12h, the CaN activities increased respectively by 13%,57%(P<0.05) and 228%(P<0.01) compared with that in non-stimulated cardiomyocytes. The CaN activities in AngⅡ-stimulated cardiomyocytes were significantly inhibited by losartan(50 μmol·L-1), H7(50 μmol·L-1)and Fura-2/AM(4 μmol·L-1),while no effect was observed with PD98059(50 μmol·L-1).The [3H]-leucine incorporation in AngⅡ-stimulated cardiomyocytes increased by 46%(P<0.01) compared with that in control group, which was dramatically inhibited by cyclosporin A(0.5~5μg/mL). CONCLUSIONS: Calcineurin, a Ca2+/calmodulin-dependent protein phosphatase, may play an important role in AngⅡ-induced cardiac myocyte hypertrophy. The activation of CaN may dependent on the sustained increases of [Ca2+]i and be regulated by some protein kinases (such as PKC,etc.).  相似文献   

4.
AIM: To study the effects of cyproheptadine (Cyp) and anisodamine (Ani) on the changes of intracellular free Ca2+ concentration ([Ca2+]i) induced by tumor necrosis factor (TNFα) in single endothelial cells, and to explore the mechanisms of TNFα mediated shock and antishock actions of Cyp and Ani. METHODS: Human umbilical vein endothelial cell strains (ECV304) were seed in 35 mm tissue culture dish with 2 mL DMEM culture medium. The cultured cells were loaded by Fluo-3/AM. The spatial distribution and the dynamic changes of [Ca2+]i in single endothelial cell was determined by laser scanning confocal microscopy (LSCM). RESULTS: [Ca2+]i in single endothelial cell after stimulation of TNFα rapidly increased in a dose-dependent manner and approached the peak value within 60 seconds, afterwards, decreased and kept above the basal level. The confocal scanning image showed that [Ca2+]i elevation was more obvious in nuclear than in cytoplasma, and decreased slowly. Cyp (3×10-5, 6×10-5 mol/L) and Ani (2×10-5, 4×10-5 mol·L-1) markedly inhibited TNFα (1.2×10-9 mol·L-1)-induced [Ca2+]i elevation. CONCLUSIONS: TNFα markedly induces elevation of [Ca2+]i in single endothelial cell, it may be an important mechanism of TNFα-induced shock and tissue injury. Cyp and Ani obviously suppress TNFα-induced [Ca2+]i elevation, which probably is one of the mechanisms of their antishock effects.  相似文献   

5.
间歇浸没式生物反应器在辰星草培养苗扩繁中的应用   总被引:1,自引:0,他引:1  
以茎尖培养得到的辰星草(Limonium hybrid‘MistyBIue’)培养苗(带2叶片)为试材。培养基为MS BA 1.0mg/L 蔗糖30g/L,pH调节为5.8。固体培养和振荡培养使用250mL三角瓶,每瓶100mL培养基。生物反应器培养使用5L气球型反应器,2L培养基。完全浸没式生物反应器培养时,无“载桥”,培养苗在培养基中始终处于浸泡状态;间歇浸没式生物反应器培养时,离反应器底部15cm处架有“载桥”,培养基定时与‘‘载桥”上的苗接触,每  相似文献   

6.
AIM:To investigate the role of expression of peroxisome proliferator-activated receptor α(PPAR α) in pathogenesis of rat fatty liver.METHODS:The rats were treated with a low dose of carbon terachloride (CCl4) and fed a high fat diet to produce fatty liver. We determined the concentrations of triglyceride (TG), total cholesterol (TC), free fatty acid (FFA) in liver and the alanine aminotransferase (ALT) activity, tumor necrosis factor-α (TNF-α), FFA in serum and the degree of hepatocytic steatosis. Total RNA of liver was extracted, and the expression of PPAR α were analyzed by semi-quantitative RT-PCR method.RESULTS:In model group, the hepatocytic PPAR α mRNA expression decreased to 0.41±0.28, compared to 1.41±0.29 in the control group (P<0.01). The contents of TG, TC, FFA in model rat liver were (1.88±0.20) mmol·L-1, (11.03±1.12) mmol·L-1 and (1 260.38±151.27) μmol·L-1, respectively, compared to (0.53±0.10) mmol·L-1, (1.25±0.25) mmol·L-1 and (334.30±27.09) μmol·L-1 in the control group (P<0.01). The activity of ALT, concentrations of TNF-α and FFA in serum were also increased remarkably in model group.CONCLUSION:Oxidation of fatty acid and utilization of lipids in liver are affected by reducing the expression of PPAR α, which result lipid accumulation in liver.  相似文献   

7.
以‘凤丹’牡丹的幼胚为材料,从取样时期、切割接种方式、基本培养基和植物生长调节剂选择等方面进行再生体系优化。结果表明:授粉后60 d为‘凤丹’牡丹幼胚诱导愈伤的最佳取材时期;完全破碎切割成幼胚薄片比完整胚、1/2胚和1/4胚更容易获得高质量的愈伤组织,且褐化率较低;MS基本培养基添加0.162μmol·L-1 H2O2可提高幼胚愈伤组织诱导率,但会增加褐化率,而在WPM基本培养基中添加不同浓度的H2O2,对愈伤诱导率和褐化率的影响不大;WPM基本培养基比MS更适于‘凤丹’牡丹幼胚再生;WPM+2.5 mg·L-1 2,4-D+0.1 mg·L-1 6-BA是诱导愈伤的最佳植物生长调节剂组合,诱导率可达93.33%;不定芽和不定根诱导的最佳组合分别为WPM+30 g·L-1蔗糖+3 g·L-1植物凝胶+0.5 mg·L-1 6-BA+0.5 mg·L-1  相似文献   

8.
9.
AIM: To study the effects of tetrandrine(Tet) and fructose-1, 6-diphosphate(FDP) on the elevated intrasynaptosomal [Ca2+]i induced by excitatory amino acids(EAA). METHODS: A rapid method for preparing synaptosomes was used, and intrasynaptosomal free calcium([Ca2+]i) was measured by using the fluorescent indicator quin-2. RESULTS: L-glutamate(Glu, 100 μmol/L), aspartate(Asp, 100 μmol·L-1), N-methy1-D-aspartate(100 μmol/L) and Glu(50 μmol/L) plus Asp(50 μmol/L) all elevated intrasynaptosomal [Ca2+]i in a dose-dependent manner. Pretreatment with Tet(10, 30, 60 μmol/L), FDP(15, 30, 75, 150 μmol/L), MK-801(10, 20 μmol/L) and Tet(15, 30 μmol/L) plus FDP(15, 30 μmol/L) all attenuated the increase in intrasynaptosomal [Ca2+]i induced by EAAs mentioned as above in a dose-dependent manner, and the effect of Tet plus FDP was most significant. CONCLUSION: Both Tet and FDP inhibited a rise in intrasynaptosomal [Ca2+]i induced by EAAs, which may be one of mechanisms that Tet and FDP pretect cerebral tissues against ischemia injury.  相似文献   

10.
11.
AIM: To investigate the effect of salvianolic acid B (Sal B) on apoptosis of rat bone mesenchymal stem cells(BMSCs) induced by hydrogen peroxide(H2O2). METHODS: BMSCs were incubated with Sal B at the concentration of 1, 10 or 100 μmol/L while treated with lethal concentration of H2O2 (500 μmol/L). The effect of Sal B at different concentrations on the viability of BMSCs was detected by MTT. Flow cytometry were used to determine the protective role of Sal B in apoptosis of BMSCs. The changes of chromatin distribution in BMSCs were observed by Hoechst 33342 staining. The expression of p-ERK1/2 was detected by Western blotting. RESULTS: Sal B protected the BMSCs against H2O2 as the cell viability was increased from (53.60±4.21)% to (85.33±9.08)% or (75.78±6.28)% in a dose-dependent manner. After exposed to H2O2, about 50%-65% BMSCs displayed apoptotic morphology. Treatment with Sal B at the concentrations of 10 and 100 μmol/L reduced the cytotoxic effect of H2O2 on BMSCs to about 32% and 47%, respectively. The results of flow cytometric analysis confirmed the cytoprotective effect of Sal B. This protective effect was concomitant with significant reduction of ROS generation. Moreover, H2O2 time-dependently induced a pronounced increase in ERK1/2 phosphorylation,which was effectively inhibited by Sal B.CONCLUSION: Sal B protects BMSCs against H2O2-induced apoptosis. Sal B may exert its protective effect on BMSCs by triggering intracellular anti-apoptosis mechanism as well as reducing the oxidative stress.  相似文献   

12.
AIM: To observe the influence of erythropoietin (EPO) on eryptosis and production of reactive oxygen species (ROS) in erythrocytes under stimulation of hydrogen peroxide (H2O2),and to explore its related mechanism. METHODS: The erythrocyte suspension (1%) was cultured in vitro and divided into 3 groups:control group (C group, the culture medium was PBS), H2O2 group (H group, the culture medium was PBS containing H2O2 at final concentration of 100 μmol/L) and EPO group (E group, the culture medium was PBS containing H2O2 at final concentration of 100 μmol/L and EPO at final concentration of 2×104 U/L). The erythrocytes were collected at 24 h and 60 h. The eryptosis was detected by flow cytometry with Annexin V staining. The production of ROS and intracellular calcium ion concentration ([Ca2+]i) were also analyzed by flow cytometry. RESULTS: The eryptosis in C group was increased as the incubating time extended. The eryptosis in H group was higher than that in C group (P<0.01), while that in E group was lower than that in H group (P<0.01). Meanwhile, ROS production and[Ca2+]i were higher in H group than those in C group (P<0.01), but those were lower in E group than those in H group (P<0.05 or P<0.01). CONCLUSION: EPO inhibits eryptosis induced by H2O2 and its mechanism may be related to antioxidant effect and change of[Ca2+]i.  相似文献   

13.
AIM: To investigate the effect of sodium ferulate on expression of apoptosis-related genes, BCl-2 and bax, in rat lens epithelial cells (LEC) injured by oxidation.METHODS: Eyes of SD rats were divided randomly into four groups: control group, hydrogen peroxide group (H2O2), pirenoxine sodium group (PS) and sodium ferulate group (SF). Eyes were excised and lenses were separated under operating microscope and sterilized condition. Lenses were incubated in CO2 incubator for 24 h with 300μmol·L-1H2O2 and with or rithout 5 mmol·L-1SF. The expression of BCl-2 and Bax protein of LEC were measured and compared by tearing the LEC anterior capsule via immunohistochemical analysis.RESULTS: (1) There were BCl-2 and Bax expression in normal lenses of SD rates, BCl-2 expression was stronger than Bax. (2) BCl-2 expression decreased and Bax expression increased markedly (P<0.01),BCl-2/Bax reduced in H2O2 group. (3) There were up regulation of BCl-2 expression and down-regulation down of Bax expression, and BCl-2/Bax increased in SF group compared with H2O2 group (P<0.01). (4) The above changes were similar between PS group and SF group, but much stronger in SF group than that in PS group (P<0.01).CONCLUSION: These results show that SF regulates expression of apoptosis-related genes, BCl-2 and bax, which may be the molecular mechanism of LEC apoptosis inhibition by SF.  相似文献   

14.
AIM:To evaluate the effect of inhibiting ubiquitin-specific protease 14(USPl4) activity on oxidative stress induced by H2O2 of H9c2 cells.METHODS:The H9c2 cells were incubated with H2O2 at 25 μmol/L for 2 h to establish the oxidative stress injury model.The cells were divided into control group,H2O2 group,IU1 group (25 μmol/L or 50 μmol/L) and IU1+H2O2 group.The H9c2 cells activity was measured by MTS assay.The level of intracellular reactive oxygen species (ROS) and cell survival rate were analyzed by flow cytometry assay.The changes of the mitogen-activated protein kinase (MAPK) family related proteins were detected by Western blot.RESULTS:Compared with control group,the cell activity and the viability rate in H2O2 group were decreased (P<0.05),while the intracellular ROS,the protein levels of Bax/Bcl-2,P53,p-ERK1/2,p-JNK and p-P38 were increased (P<0.05).Compared with H2O2 group,the cell activity and the viability rate of the H9c2 cells in IU1+H2O2 group were increased (P<0.05),while the intracellular ROS,the protein levels of Bax/Bcl-2,P53,p-ERK1/2,p-JNK and p-P38 were decreased (P<0.05).CONCLUSION:Inhibition of USPl4 activity reduces the oxidative stress injury of the H9c2 cells.The mechanism may be related to inhibition of the MAPK signaling and down-regulation of apoptosis related proteins.  相似文献   

15.
以番茄品种合作903为试验材料,设置0、0.1、0.2、0.4 mmol · L~(-1 )亚精胺(Spd)浸种10 h,研究不同浓度Spd浸种对番茄种子萌发、幼苗生长及高温抗性的影响。结果表明:不同浓度Spd浸种处理均能显著提高番茄种子的发芽指数和活力指数,幼苗地下部干质量和壮苗指数明显提高,其中0.2 mmol · L~(-1 )Spd浸种处理发芽最快,活力指数最高。Spd浸种处理降低了高温胁迫下番茄叶片的相对电解质渗透率、丙二醛(MDA)和H_2O_2含量,其中0.2 mmol · L~(-1 )Spd处理的相对电解质渗透率、MDA和H_2O_2含量最低;抗氧化酶(SOD、APX、DHAR)活性增加,并在0.2 mmol · L~(-1)时达到最大值。综上,0.2 mmol · L~(-1 )Spd浸种能有效促进番茄种子萌发和幼苗生长,提高番茄幼苗高温抗性。  相似文献   

16.
AIM: To observe the expression of 26S proteasome LMP2 subunit in vascular endothelial cells (VECs) under oxidative stress, and to evaluate its role in the development of tolerance against oxidative stress in VECs. METHODS: The cell model of H2O2 preconditioning-induced oxidative tolerance was established in VECs. The expression of LMP2 was detected by cellular immunofluorescent labeling and Western blotting. The LMP2 anti-sense and sense oligonucleotides were transfected into VECs by LipofectamineTM 2000. The damages of VECs were evaluated by detecting the activity of lactate dehydrogenase (LDH) and the concentration of malondialdehyde (MDA) in the culture medium. RESULTS: H2O2 (500 μmol/L for 3 h) induced oxidative stress in VECss in a dose- and the activity of time-dependent manner, characterized by the increase in the concentration of MDA and LDH in the culture medium. Pretreatment with H2O2 (10 μmol/L for 24 h) up-regulated the expression of LMP2. Meanwhile, the capacity of cellular tolerance against oxidative stress induced by H2O2 was increased as the concentration of MDA and the activity of LDH in the culture medium significantly decreased. Compared with H2O2 group, up-regulation of LMP2 by IFN-γ pretreatment (20 μg/L for 48 h) increased the tolerance of VECs against H2O2 injury, and the MDA conentration and the activity of LDH in the culture medium also significantly decreased. Transfection with LMP2 antisense oligonucleotide partly inhibited the increased expression of LMP2 induced by IFN-γ in VECs and abolished the tolerance against H2O2. CONCLUSION: The 26S proteasome LMP2 subunit is associated with the development of the tolerance against H2O2-induced oxidative stress in VECs.  相似文献   

17.
AIM: To investigate the effects of mollugin on the viability and collagen synthesis of rat hepatic stellate cell line CFSC-2G. METHODS: The activation of CFSC-2G cells was induced with low concentration (10 μmol/L) of hydrogen peroxide (H2O2) for 30 min in the experiment. The viability of the CFSC-2G cells after exposed to mollugin at different concentrations (0, 20, 40, 60 and 120 μmol/L) was detected by MTT assay. The mRNA and protein expression levels of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), nuclear factor-κB (NF-κB) p65, Bcl-2, Bcl-xL, Bax, and hepatic stellate cell activation markers α-smooth muscle actin (α-SMA) and collagen type I (Col Ⅰ) were detected by real-time PCR and Western blot. The phosphorylation level of p38 mitogen-activated protein kinase (p38 MAPK) was determined by Western blot. RESULTS: Mollugin significantly inhibited the viability and collagen synthesis of activated CSFC-2G cells induced by H2O2. The expression of Nrf2, HO-1 and Bax at mRNA and protein levels, and the phosphorylation level of p38 MAPK were promoted, while the levels of NF-κB p65, Bcl-2, Bcl-xL, α-SMA and ColⅠwere inhibited by mollugin (P<0.05). CONCLUSION: Mollugin may inhibit H2O2-induced viability and collagen synthesis of the CSFC-2G cells by activating Nrf2 and HO-1, and blocking the NF-κB p65 and Bcl-2 expression.  相似文献   

18.
AIM: To evaluate the effect of senegenin (Sen) on H2O2-treated retinal ganglion cells (RGCs) and to explore its underlying mechanisms. METHODS: RGCs were retrograde labeled by injection of fluorogold into the superior colliculi of SD rats on the postnatal day 3. On the postnatal days 6 to 8, the retinas were dissociated with papain and cultured. Primary RGCs cultured in vitro were treated with H2O2 and/or various doses of Sen. The viability of RGCs was evaluated by counting the fluorescence-labeled neurons under microscope. The morphological changes of the nuclei in the retinal neurons were observed by Hoechst 33258 staining. Western blotting was applied to determine the expression of cleaved caspase-3, cytochrome C and Bcl-2 in cultured retinal neurons. RESULTS: Compared with the control cells, Sen at doses of 10, 20 or 40 μmol/L had no toxicity to RGCs (P>0.05). However, Sen at doses of 80 and 160 μmol/L had significant toxicity to RGCs (P<0.01). Compared with H2O2-injured group, Sen at doses of 10, 20 and 40 μmol/L effectively protected against H2O2-induced injury in RGCs (P<0.05) with the best efficiency at 40 μmol/L. Hoechst 33258 staining showed that the neuronal apoptosis caused by H2O2 was reduced by Sen. The results of Western blotting showed an up-regulation of Bcl-2, and decreased cytochrome C and cleaved caspase-3 levels by Sen in H2O2-treated retinal neurons. CONCLUSION: Sen is able to protect RGCs from H2O2-induced injury by enhancing Bcl-2 expression and inhibiting cell apoptosis.  相似文献   

19.
AIM: To investigate whether oxidative stress is able to induce autophagy in mesenchymal stem cells (MSCs), and to explore the effects of autophagy on MSC proliferation and apoptosis under oxidative stress circumstance as well as the underlying mechanism for promoting the therapeutic effects of transplanted MSCs on treating diabetes mellitus erectile dysfunction (DMED). METHODS: Hydrogen peroxide (H2O2) was applied to simulate the oxidative stress circumstance. The effects of H2O2 at concentration of 0, 50, 100, 200, 400 μmol/L on the viability of MSCs were tested by the method of Trypan blue exclusion and MTT assay respectively . The methods of MTT assay, Western blot and transmission electron microscope (TEM) were used to explore the effects of H2O2 on MSC apoptosis and autophagy. RESULTS: The proliferation of MSCs was obviously inhibited by H2O2 in a dose-dependent manner (P<0.01) and the 50% inhibiting concentration (IC50) was (384.58±16.89) μmol/L. H2O2 induced apoptosis and autophay of MSCs. The proliferation rate of MSCs was suppressed by H2O2 significantly (P<0.05), with a further decline by blockade of autophagy (P<0.05) whereas increased by blockade of apoptosis (P<0.05). H2O2 induced MSCs apoptosis obviously (P<0.05), with an augment of apoptosis (P<0.05) by blockade of autophagy. Furthermore, the H2O2 increased expression of cleaved caspase-3 and cleavage of poly ADP-ribose polymerase 1 (PARP1), Which were decreased by apoptosis blockade whereas were enhanced by blockade of autopahgy. CONCLUSION: Oxidative stress plays a dual role in MSC survival, which induces MSC apoptosis and autophagy. Moreover, blockade of autophagy intensifies MSC apoptosis. Therefore, it is a promising method to ameliorate the effects of stem-cell based therapy on DMED by enhancing protective autophagy to increase the survival rate of transplanted MSCs against oxidative stress circumstance caused by diabetes mellitus.  相似文献   

20.
以南瓜自交系北观(Cucurbita maxima)为材料,利用正交设计L16(45)优化南瓜MSAP 预扩增和选择性扩增体系的主要因素。结果表明,第一步最佳酶切时间2 h,Hap Ⅱ(HpaⅡ,MspⅠ)用量0.5 μL;第二步酶切时间6 h,EcoR Ⅰ用量0.4 μL;连接体系包括酶切产物21 μL,EcoR Ⅰ接头(5 μmol · L-1)、Hap Ⅱ接头(5 μmol · L-1)各1.0 μL,连接时间12 h,T4 DNA Ligase 用量为0.5 μL;最佳预扩增反应体系(25 μL)包含2.0 μL 连接产物,1.5 μL 10 × PCR Buffer(Mg2+ plus),2.0 μL dNTP(2.5 mmol · L-1),0.6 μL Taq 酶(5 U · μL-1),0.4 μL 上下游引物(10 μmol · L-1);最佳选择性扩增反应体系为预扩增产物稀释120 倍的模板4.0 μL,其他同预扩增体系。最后,利用建立好的MSAP 体系进行6% 聚丙烯酰胺凝胶电泳验证并筛选出适于南瓜MSAP 分析的36 对引物,表明优化后的MSAP 体系多态性好,体系稳定,可重复,为后续进行南瓜MSAP 分析奠定了基础。  相似文献   

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