Xuefu Zhuyu Oral Liquid (血府逐瘀口服液) Prevents Apoptosis of Ischemic Myocardium Cells in Rats by Regulating SIRT1 and Its Pathway-Related Genes

Objective: To observe the changes of ischemic myocardial cells apoptosis in rats following intervention with Xuefu Zhuyu Oral Liquid(血府逐瘀口服液, XFZY), as well as changes of protein expression of silent information regulator 1(SIRT1) and SIRT1 pathway-related genes. Methods: H9c2 rat myocardial cells were divided into 6 groups: control group, oxygen glucose deprivation(OGD) group, SIRT1 siRNA group, OGD+SIRT1 siRNA group, OGD+XFZY group, and OGD+SIRT1 siRNA+XFZY group. Quantitative fluorescent polymerase chain reaction(PCR) and Western blot were used to detect the concentration variations of SIRT1 and its pathway-related genes and corresponding protein expression after XFZY intervention and SIRT1 transfection. Results: Compared with the control group, the m RNA and protein expressions of SIRT1 were decreased obviously, while the mRNA and protein levels of P53, forkhead box protein O1(FoxO1), FoxO3, FoxO4 and nuclear factor kappa B(NF-κB) were increased in the OGD group, SIRT1 siRNA group, and OGD+SIRT1 siRNA group(P0.01). Compared with the OGD group and OGD+SIRT1 siRNA group, the treatment of XFZY inhibited the decline in SIRT1 mRNA and protein expressions(P0.01), and down-regulated the mRNA and protein levels of P53, FoxO1, FoxO3, FoxO4 and NF-κB, respectively(P0.05 or P0.01). Conclusion: XFZY could prevent myocardial cells apoptosis probably by increasing the mRNA and protein expressions of SIRT1 and inhibiting the m RNA and protein expressions of P53, NF-κB, FoxO1, FoxO3 and FoxO4.     

Effects of Hirudin on High Glucose-Induced Oxidative Stress and Inflammatory Pathway in Rat Dorsal Root Ganglion Neurons

Objective: To investigate protective effects of hirudin on oxidative stress and apoptosis of spinal dorsal root ganglion cells in high-glucose rats at the cellular and molecular level. Methods: Dorsal root ganglion neurons(DRGn) were harvested from embryonic day in 15 SD rats, purified and identificated after primary culture. They were divided into the normal control group, high-glucose(HG) group, positive control(alpha-lipoic acid, ALA) group, low-dose hirudin group(H1), medium-dose hirudin group(H2) and high-dose hirudin group(H3). The control group was cultured by neuron specific culture medium, while the HG group was cultured by neuron specific culture medium and 20 mmol/L glucose(HG medium). The hirudin groups were cultured by HG medium+0.25 IU/mL hirudin(H1), HG medium+0.5 IU/mL hirudin(H2) and HG medium+1 IU/mL hirudin(H3). The ALA group was cultured by HG medium+100 μmol/L ALA. 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenylt etrazolium bromide(MTT) assay was used to explore the optimum concentration and intervention time. Flow cytometry assay was used to detect the level of reactive oxygen series(ROS). Western blot and quantificational realtime polymerase chain reaction(qRT-PCR) were used to detect the expression of protein and mRNA of nuclear factor erythroid 2-related factor 2(Nrf-2), hemeoxygence-1(HO-1), nuclear factor-κB(NF-κB) and Caspase-3. TUNEL assay was used to test the apoptosis rate of different groups. Results: After 24 h of culture, the cell activity of hirudin and ALA groups were higher than that of HG group, and there was a statistical difference between the H1 group and HG group(P0.05). In hirudin groups, the apoptosis rate of cells, the expression of activated Caspase-3 protein and Caspase-3 mRNA were lower than those of HG group(P0.01), higher than those of ALA group(P0.01 or P0.05). The ROS level of hirudin groups was higher than that of ALA group(P0.01), lower than that of HG group(P0.01 or P0.05). The expression of NF-κB(P65) protein in H3 group were lower than those of HG group(P0.05). The expression of Nrf-2 protein in hirudin groups was higher than that of HG group(P0.01), lower than that of ALA group(P0.01 or P0.05). The expression of HO-1 protein in hirudin groups was lower than that of ALA group(P0.01 or P0.05), higher than that of HG group(P0.01 or P0.05). Conclusions: The activity of DRGn cells can be promoted by hirudin under HG conditions. The effects of hirudin on the inhibition of HG on DRGn cells damage mainly include scavenging ROS, up-regulating Nrf-2/HO-1 pathway, inhibiting activation of NF-κB pathway, down-regulating the expression of and Caspase-3 and reducing DRGn cell apoptosis.     

鞘内注射代谢性谷氨酸受体亚型5拮抗剂对骨癌痛小鼠痛行为及脊髓水平星形胶质细胞活化的影响

目的 探讨代谢性谷氨酸受体亚型5(mGluR5)拈抗剂MTEP的抗癌痛作用及其机制.方法 C3H/HeNCrlVr雄性小鼠60只,随机分为:(1)正常组:正常饲养21d;(2)MTEP+Tumor组:癌痛组从第14d开始鞘内注射MTEP150nmol,1次/d,共7次;(3)生理盐水+Tumor组:以等体积的生理盐水代替MTEP;(4)MTEP+Sham组:用等剂量MTEP给予假手术组;(5)生理盐水+Sham组:用等体积的生理盐水给予假手术组.每组12只小鼠.用热辐射刺激仪测定缩足潜伏期(PWTL).各组小鼠均在第21d行为学测试后取脊髓标本,分别应用Real-time PCR和western blot检测胶质细胞纤维酸性蛋白(GFAP)mRNA及蛋白的表达.结果 各组小鼠基础PWTL差异无统计学意义(P＞0.05).在术后14d,与正常组相比,假手术组PWTL差异无统计学意义(P＞0.05),而癌痛组PWTL明显降低(P＜0.05).在术后21 d,和正常组相比,MTEP+Sham组、生理盐水+ShaT组PWTL、脊髓GFAP表达差异均无统计学意义(P＞0.05);生理盐水+Tumor组PWTL[(6.18±1.29)s]明显低于正常组[(15.91±1.65)s]、生理盐水+Sham组[(16.57±1.86)s]和MTEP+Sham组[(17.05±2.43)s](P＜0.05),脊髓水平GFAP表达则高于上述3组;MTEP+Tumor组PWTL[(9.39±1.94)s]高于生理盐水+Tumor组,脊髓水平GFAP表达则低于生理盐水+Tumor组(P＜0.05).结论 鞘内注射MTEP具有抗癌痛作用,抑制脊髓水平星形胶质细胞活化可能是其机制之一.

Abstract：

Objective To investigate effects of metabotropic glutamate receptor subtype 5 (mGluR5) antagonist MTEP on the nociceptive behavior and the expression of glial fibrillary acidic protein (GFAP) in spinal cord associated with bone cancer pain. Methods C3H/HeNCrlVr 60 male mice were randomly divided into 5 groups: ( 1 ) normal control group: the mice were given food and water ad libitum; ( 2 ) MTEP + Tumor group: the mice were treated by intrathecal gdministration ( once daily on the days 14 ～20 after inoculation of tumor cells)with MTEP (150 nmol); (3) physiological saline + Tumor group:the tumor mice were treated with the same volume of physiological saline; (4) MTEP + Sham group: the sham mice were treated with the same dose of MTEP;(5) physiological saline + Sham group: the sham mice were treated with the same volume of physiological saline.the mice pain behaviors were assessed with the paw withdrawal thermal latency (PWTL) at the corresponding time points, then the mice were killed and the samples of spinal cord were used to real-time PCR and western blot detection of GFAP mRNA and protein expression. Results The basic values of PWTL had no significant differences among all groups (P＜0.05). At day 14 after operation,no significant difference was found in the PWTL value between normal control group and the sham operation group. But in tumor group, the PWTL value was significantly lower than in the normal control group (P＜ 0.05 ). At day 21 after operation,the PWTL and the level of GFAP expression in the spinal cord had no significant differences among normal control group, MTEP + Sham group and physiological saline + Sham group (P ＞ 0.05 ); the PWTL ( (6. 18 ± 1.29 ) s) in physiological saline + Tumor group was significantly lower than in normal control group ( ( 15.91 ± 1.65 )s), physiological saline + Sham group ( ( 16.57 ± 1.86) s) and MTEP + Sham group ( ( 17.05 ± 2.43 ) s) (P ＜ 0.05 ), but the level of GFAP expression was higher than in the above three groups. In MTEP +Tumor group ,the PWTL (9.39 ± 1.94s) was higher than in physiological saline + Tumor group, and the level of GFAP expression was lower than in physiological saline +Tumor group (P ＜ 0.05 ). Conclusion Inhibiting spinal activation of astrocytes may be one of the MTEP anticancer pain mechanisms.     

Effects of Panax Quinquefolium Saponin on Phosphatidylinositol 3-Kinase/Serine Threonine Kinase Pathway of Neonatal Rat Myocardial Cells Subjected to Hypoxia

Objective:To explore the effects of Panax Quinquefolium Saponin(PQS) on phosphatidylinositol3-kinase/serine threonine kinase(PI3K/Akt) pathway of neonatal rat myocardial cells subjected to hypoxia.Methods:Neonatal rat myocardial cells were cultured in vitro.After the myocardial cell injury was induced by hypoxia,the cells were randomized into 5 groups:the normal group,the model group,the positive control group(Ciclosporin A,2 μ mol/L),the low-dose PQS group(PQSL,25mg/L),and the high-dose PQS group(PQSH,50 mg/L).Morphology and behavior of myocardial cells were observed under an inverted microscope.Apoptosis rate and lactate dehydrogenase(LDH) leakage rate of myocardial cells were determined by colorimetry.Mitochondrial transmembrane potential was assessed using a fiuorexon laser.Phospho-glycogen synthase kinase(GSK)-3 β and phospho-Akt as well as cytochrome C were determined by Western blot.Results:LDH leakage in the Ciclosporin A group,PQSH group and PQSL group reduced progressively compared with the model group(P0.05).Akt and GSK-3 β was strongly phosphorylated after treatment with Ciclosporin A and PQS compared with the model group(P0.05,P0.01).Compared with the model group(16.41 ±1.74;35.28 ±6.30),both the integrated optical density of mitochondrial permeability transition pore(MPTP) and the mitochondrial transmembrane potential significantly increased in the PQSH group(42.74 + 2.12;71.36 ±6.54) and the PQSL group(39.58 ±1.49;66.99 ±5.45;P0.05,P0.01).However,the protein of cytochrome C outside the mitochondrion decreased in the PQSH group(273.66 ±14.61) and the PQSL group(259.62 ±17.31) compared with the model group(502.41 ±17.76;P0.05).Conclusion:Through activation of the PI3K/AW pathway and inhibition of the MPTP,PQS might protect the heart against ischemia injury and apoptosis of myocardial cells.     

Effects of Senegenin against Hypoxia/Reoxygenation-Induced Injury in PC12 Cells

Objective:To investigate the effect and the potential mechanism of Senegenin(Sen) against injury induced by hypoxia/reoxygenation(H/R) in highly differentiated PC12 cells.Methods:The cultured PC12 cells were treated with H/R in the presence or absence of Sen(60 μmol/L).Four groups were included in the experiment:control group,H/R group,H/R+Sen group and Sen group.Cell viability of each group and the level of lactate dehydrogenase(LDH) in culture medium were detected for the pharmacological effect of Sen.Hoechst 33258 staining and annexin V/propidium iodide double staining were used to analyze the apoptosis rate.Moreover,mitochondrial membrane potential(△Ψm),reactive oxygen species(ROS) and intracellular free calcium([Ca~(2+)]i) were measured by fluorescent staining and flow cytometry.Cleaved caspase-3and activity of NADPH oxidase(NOX) were determined by colorimetric protease assay and enzyme linked immunosorbent assay,respectively.Results:Sen significantly elevated cell viability(P0.05),decreased the leakage of LDH(P0.05) and apoptosis rate(P0.05) in H/R-injured PC12 cells.Sen maintained the value of△Ψm(P0.05) and suppressed the activity of caspase-3(P0.05).Moreover,Sen reduced ROS accumulation(P0.05) and[Ca~(2+)]i increment(P0.05) by inhibiting the activity of NOX(P0.05).Conclusion:Sen may exert cytoprotection against H/R injury by decreasing the levels of intracellular ROS and[Ca~(2+)]_i,thereby suppressing the mitochondrial pathway of cellular apoptosis.     

Puerarin Up-regulates Methyl-CpG Binding Protein 2 Phosphorylation in Hippocampus of Vascular Dementia Rats

Objective: To observe the effect of puerarin on methyl-CpG binding protein 2(MeCP2) phosphorylation(pMeCP2) in the hippocampus of a rat model of vascular dementia(VD). Methods: Thirty-six healthy Sprague-Dawley rats were randomly assigned to the sham-operated group, dementia group and puerarintreated group using a random number table(n=12 per group). The modified permanent bilateral common carotid artery occlusion method was used to establish the VD model. The sham-operated and dementia groups were given 2 m L/d of saline, while the puerarin-treated group was given 100 mg/(kg·d) of puerarin for 17 days. The learning and memory abilities were evaluated by the Morris water maze test. Hematoxylin-eosin staining, immunohistochemical(IHC) staining and Western blot analysis were carried out to observe changes in neuron morphology and in level of pMeCP2 in the hippocampus, respectively. Results: The morphologies of rat hippocampal neurons in the puerarintreated group were markedly improved compared with the dementia group. The escape latency of the dementia group was significantly longer than the sham-operated group(P0.05), while the puerarin-treated group was obviously shorter than the dementia group(P0.05). Cross-platform times of the dementia group were significantly decreased compared with the sham-operated group(P0.05), while the puerarin-treated group was obviously increased compared with the dementia group(P0.05). IHC staining showed no significant difference in the number of MeCP2 positive cells among 3 groups(P0.05). The number of pMeCP2 positive cells in the CA1 region of hippocampus in the dementia group was significantly increased compared with the sham-operated group, and the puerarin-treated group was significantly increased compared with the dementia group(both P0.05). Western blot analysis showed no significant difference of MeCP2 expression among 3 groups(P0.05). The expression of pMeCP2 in the dementia group was significantly increased compared with the sham-operated group, while it in the puerarin-treated group was significantly increased compared with the dementia group(P0.05). Conclusion: Puerarin could play a role in the protection of nerve cells through up-regulating pMeCP2 in the hippocampus, improving neuron morphologies, and enhancing learning and memory ablities in a rat model of VD.     

Qushi Huayu Decoction (祛湿化瘀方) Inhibits Protein and Gene Expression of Cathepsin B in HepG2 Cells Induced by Free Fatty Acids

Objective: To study the experimental efficacy of Qushi Huayu Decoction (祛湿化瘀方,QHD) on protein and gene expression of cathepsin B (ctsb) in HepG2 cells induced by free fatty acids (FFAs).Methods: The model of HepG2 steatosis and tumor necrosis factor-α (TNF-α) secretion was induced by long-chain FFAs.HepG2 cells were divided into 4 groups: control group (group C),model group (group M),low-dose QHD group (group L) and high-dose QHD group (group H ).Long-chain FFAs were added to groups M,L and H.The 10% blank-control serum was added to group C and M,while 5% and 10% QHD-containing sera were added to group L and H,respectively.The levels of serum TNF-α and cellular triglyceride (TG) were detected.Cellular p-IκB and ctsb expression were detected using Western blot and PCR.The expression and distribution of ctsb were observed by immunofluorescence.Results: After incubating with FFA for 24 h,TG deposition in HepG2,TNF-α content in cell supernatant,the protein expression of cellular ctsb and P-IκB,as well as mRNA expression of ctsb increased markedly in group M compared with group C (P0.05,P0.01).Compared with group M,TG deposition,the expression of cellular ctsb,P-IκB and ctsb mRNA in groups L and H,as well as TNF-α content in group H,decreased significantly (P0.05).Cell immunochemical fluorescence studies showed that ctsb was released from lysosomes and distributed in the cytoplasm extensively and diffusedly after being stimulated with FFA.In this study,these above-mentioned changes were inhibited markedly in groups L and H.Conclusion: QHD might have a direct inhibitory effect on the ctsb target in the FFA-ctsb-TNFα pathway of hepatic lipotoxicity.     

Shenmai Injection(参麦注射液) Inhibiting the Extracellular Signal Regulated Kinase-lnduced Human Airway Smooth Muscle Proliferation in Asthma

<正>Objective:To investigate the relationship between the proliferation of sensitized human airway smooth muscle cells(HASMCs)and the expression of extracellular signal regulated kinase(ERK)and the effect of Shenmai Injection(参麦注射液,SMI)on HASMCs.Methods:The HASMCs cultured in vitro were divided into three groups:(1)control group;(2)sensitized group:containing 10%asthmatic serum;(3)SMI group:further divided into three different concentration subgroups interferred with 10μL/mL,50μL/mL,and 100μL/mL SMI, respectively.The proliferation of HASMCs was detected using MTT method,the expression of proliferating cell nucleus antigen(PCNA)in HASMCs was detected using immunocytochemical staining,and the expression of phosphoration-ERK1/2(p-ERK1/2)protein was detected using Western-blot.Results:After passive sensitization, the optical density value(A_(490)value)of HASMCs was significantly increased from 0.366±0.086 to 0.839±0.168(P0.05).In addition,the expression of PCNA was significantly increased from 28.7%±5.9%in the control group to 69.8%±7.5%in the sensitized group(P0.05).At the same time,the expression of p-ERK1/2 in passively sensitized HASMCs was significantly increased compared with the control group(all P0.05).After application of 10μL/mL,50μL/mL,and 100μL/mL SMI to the cultured media of passively sensitized group,the A_(570)value was significantly decreased from 0.839±0.168 to 0.612±0.100,0.412±0.092,and 0.339±0.077, respectively(P0.05).Moreover,the expression of PCNA was significantly decreased from 69.8%±7.5%to 57.8%±6.2%,40.7%±5.4%,and 26.1%±5.2%,respectively.At the same time,the expression of p-ERK1/2 in each SMI group was significantly decreased compared with the sensitized group(ail P0.05).Conclusion:ERK signal transduction pathway may be involved in the airway remodeling in asthma.The expression of ERK can be inhibited by SMI in a dose-dependent manner,thus preventing the proliferation of HASMCs.     

蜕皮甾酮对H2O2诱导的PC12细胞毒的保护作用

目的观察蜕皮甾酮(ecdysterone,ECR)对H2O2作用不同时间诱导PC12毒的保护作用。方法通过MTT(3-4,5-d im ethylth iazolyl-2,5-d iphenyltetrazolium brom ide,MTT)法检测H2O2对PC12的毒性及ECR的保护作用。PC12细胞的形态学改变通过荧光显微镜观察(acrid ine orange/eth id ium brom ide染色,AO/EB),完整无损的PC12细胞呈绿色,受损或死亡细胞呈橘黄色和红色。结果1、25、50和100μmol.L-1ECR与PC12细胞分别作用6h,12hand 24h时,PC12细胞的MTT吸光值无明显改变;50、100、200μmol.L-1H2O2分别与PC12作用6h,12h,24h时,PC12细胞的MTT吸光值明显降低(P<0.05,P<0.01 andP<0.01);如果用不同浓度的ECR(1、25、50 and100μmol.L-1)预处理PC12细胞0.5 h后,再加入H2O2(100μmol.L-1)并分别作用6h,12h,24h,则PC12细胞的MTT吸光值相对增加(P<0.05 at 50μmol.L-1,P<0.01 at 100μmol.L-1)。AO/EB染色后荧光显微镜下观察,ECR对H2O2引起的PC12细胞损伤有保护作用。结论ECR能够相对增加PC12细胞的存活率,对H2O2的PC12细胞毒性有保护作用。     

H_2O_2对PC12细胞Caspase-3和NF-κB P65基因表达的影响

目的 :探讨H2 O2 对PC12细胞半胱天冬酶 3(caspase 3)和核转录因子 kappaBP6 5 (uclearfactor kappaB ,NF κBP6 5 )基因表达的影响。方法 :不同剂量H2 O2 (0～ 4 0 0nmol·L-1)处理PC12细胞 8h ,采用RT PCR检测Caspase 3、NF κBP6 5mRNA表达变化 ,Westernblot检测Caspase 3P 2 0活性片段和NF κBP6 5蛋白表达的变化 ,用比色法检测Caspase 3相对活性。结果 :随H2 O2 浓度从 10 0～ 4 0 0nmol·L-1增加 ,Caspase 3、NF κBP6 5mRNA表达和Caspase 3P2 0活性片段及NF κBP6 5蛋白表达水平逐渐增加 ;随H2 O2 浓度从 5 0～ 4 0 0nmol·L-1增加 ,Cas pase 3相对活性增加 (P <0 .0 5 ) ,在 4 0 0nmol·L-1H2 O2 时Caspase 3相对活性达最大值。 结论 :H2 O2 可剂量依赖性的增加Caspase 3mRNA表达和Caspase 3P 2 0活性片段 ,增加Caspase 3活性 ;H2 O2 可剂量依赖性的增加NF κBP6 5mRNA表达和NF κBP6 5蛋白表达。     

姜黄素对过氧化氢诱导内皮细胞凋亡及衰老的影响

目的 探讨姜黄素对过氧化氢(H2O2)诱导人脐静脉内皮细胞(HUVECs)自噬、凋亡及衰老的影响.方法 体外培养HUVECs,分为对照组(只给予培养基),模型组(给予60 μmol/L H2O2),姜黄素组(给予60μmol/L H2O2+ 10 μmol/L姜黄素),3-MA组[(给予60 μmol/L H2O2+ 10μmol/L姜黄素+1 mmol/L3-甲基腺嘌呤(3-Methyladenine)],培养4d后,DCFH-DA法检测细胞培养液中活性氧(ROS)的含量,流式细胞仪检测细胞凋亡水平,衰老相关β-半乳糖苷酶(SA-β-gal)染色检测细胞衰老程度,Western blot技术检测自噬相关蛋白LC3和p62的表达水平.结果 与对照组相比,模型组ROS含量、凋亡率、SA-β-gal阳性率及p62水平升高(均P＜0.05),而LC3-Ⅱ/Ⅰ比值差异无统计学意义(P＞0.05).与模型组比,姜黄素组ROS含量、凋亡率及SA-β-gal阳性率及p62水平降低(均P＜0.05),但LC3-Ⅱ/Ⅰ比值升高(P＜0.05).与姜黄素组比较,3-MA组ROS含量、凋亡率、SA-β-gal阳性率及p62水平升高(均P＜0.05),但LC3-Ⅱ/Ⅰ比值降低(P＜0.05).结论 姜黄素可减轻H2O2诱导内皮细胞凋亡及衰老,其机制与提高内皮细胞自噬有关.     

NAD对AngⅡ诱导的心肌成纤维细胞Ⅰ型胶原mRNA表达的影响

目的   探讨烟酰胺腺嘌呤二核苷酸(NAD) 对血管紧张素II（AngII)诱导的大鼠心肌成纤维细胞I型胶原mRNA表达的作用。方法   提取新生Wistar大乳鼠原代心肌成纤维细胞,传代培养,采用2~4代细胞。实验分为空白对照组,AngII (0.01、 0.1、 1μmol／L)组,NAD(250μmol／L)组, AngII(1μmol／L)+ NAD (250μmol／L )组,FAM组,Sirt1-siRNA+AngII(1μmol／L)组,Sirt1-siRNA 组,Sirt1-siRNA+ NAD（250μmol／L）组,Sirt1-siRNA+Ang II(1mol／L)+NAD（250μmol／L）组。刺激24h后,提取总RNA, Real time RT-PCR法分别检测SIRT1和I型胶原mRNA的表达。结果   心肌成纤维细胞I型胶原mRNA的表达随着AngⅡ浓度升高明显增加(P＜0.05),呈浓度依赖性。与空白对照组比较,NAD（250μmol／L）组SIRT1 mRNA表达增高(P＜0.05)。与AngⅡ（1μmol／L）组比较,AngII (1μmol／L)+ NAD(250μmol／L )组I型胶原mRNA的表达明显减少(P＜0.01)。相对于FAM组,Sirt1-siRNA转染后各组SIRT1 mRNA的表达减少(P＜0.05),而心肌成纤维细胞I型胶原mRNA表达增多(P＜0.05)。结论   NAD可以抑制心肌成纤维细胞 I型胶原mRNA的表达,SIRT1影响I型胶原mRNA的表达,它们对Ang II诱导的心肌纤维化有保护作用。     

AMPK/STAT1通路参与土木香内酯改善H2O2引起的神经细胞PC12凋亡

目的：研究土木香内酯（ALA）对H2O2诱导神经细胞PC12凋亡的影响。方法：用不同浓度（1、5、10、20、50和100 μmol/L）的ALA处理细胞后进行MTT检测细胞增殖;用不同浓度（1和5 μmol/L）的ALA预先处理细胞后加入H2O2刺激细胞,进行流式和MTT检测细胞增殖情况;设立对照组、H2O2（100 μmol/L）组、ALA（1和5 μmol/L）组,ALA干预H2O2处理的细胞进行细胞流式检测细胞凋亡情况,MTT检测细胞增殖情况,Western blot检测AMPK和STAT1的磷酸化;利用siRNA沉默AMPK表达后再用ALA处理,Western blot检测STAT1的磷酸化的表达。结果：高浓度ALA抑制PC12细胞增殖;与对照组比,经H2O2刺激后PC12细胞凋亡增高;与H2O2组比较,ALA组细胞凋亡明显降低,并呈剂量依赖性;沉默AMPK表达不影响H2O2诱导PC12细胞STAT1的磷酸化表达;在沉默AMPK后再用ALA处理,与单沉默AMPK比较,STAT1的磷酸化的表达差异无统计学意义。结论：ALA可通过AMPK的激活调控H2O2诱导PC12细胞的STAT1的磷酸化表达,从而影响细胞凋亡。     

N-硬脂酰酪氨酸对H2O2诱导PC12细胞氧化应激损伤的影响

目的研究N-硬脂酰酪氨酸（NsTyr）预处理对过氧化氢（H2O2）诱导的PC12细胞氧化应激损伤的影响。方法体外培养传代的PC12细胞分为空白对照组、H2O2损伤组（不同浓度H2O2诱导16h）和NsTyr预处理组（不同浓度NsTy预处理30min后加入100μmol／LH2O2诱导16h）。流式细胞仪检测细胞凋亡率及活性氧类（ROS）生成,Westernblotting检测Bax和Bcl-2的表达。结果与H2O2（100μmol／L）损伤组比较,5、10μmol／LNsTyr预处理组PC12细胞存活率显著升高（P〈0．01）,凋亡细胞率降低（P〈0．05）,细胞内ROS生成减少（P〈0．05,P〈0．01）,Bcl-2／Bax比值升高（P〈0．05）。结论NsTyr能提高PC12细胞的抗氧化应激损伤能力,上调Bcl-2表达和下调Bax表达,抑制细胞凋亡。     

硫化氢对急性肺损伤大鼠肺组织核转录因子κB及细胞间黏附分子1表达的影响

目的 探讨硫化氢(H2S)对油酸诱导的急性肺损伤(ALI)大鼠肺组织核转录因子κB(NF-κB)与细胞间黏附分子1(ICAM-1)表达的影响.方法 雄性SD大鼠42只,采用随机数方法分为对照组(6只)、油酸组及油酸+硫氢化钠(NaHS)组,后2组大鼠分别在2、4、6h3个时间点进行观察,每个时间点大鼠为6只.复制大鼠ALI模型,对照组大鼠经过尾静脉注射0.1 ml/kg生理盐水;油酸组大鼠通过尾静脉注射油酸0.1 ml/kg;油酸+NaHS组大鼠先腹腔注射NaHS 56 μmol/kg(溶于0.5 ml生理盐水),30 min后经大鼠尾静脉注射油酸0.1 ml/kg.对支气管肺泡灌洗液沉渣行瑞士染色进行白细胞分类计数;对大鼠肺组织病变进行半定量肺损伤评分;测定肺组织中H2S的含量;应用免疫组织化学法对肺泡上皮细胞中ICAM-1表达进行定位及半定量分析,并对NF-κB核转位进行半定量分析.结果 油酸组大鼠2、4、6h支气管肺泡灌洗液多形核白细胞(PMN)比例[(74.5±3.0)％、(80.2±2.0)％和(87.2±2.7)％]及肺损伤评分(5.2±0.8、6.4±0.6和6.8±0.8)均明显高于对照组[(3.1±1.6)％和0.4±0.6,均P＜0.01];肺组织中H2S含量均明显低于对照组[ (21.20 ±0.38) μmol/g、( 20.80±0.53)μmol/g、(18.92±0.75)μmol/g比(26.81±0.65)μmol/g,均P＜0.01];肺泡上皮细胞中NF-κB核表达和ICAM-1胞膜表达则均明显高于对照组(均P＜0.05).油酸+NaHS组支气管肺泡灌洗液PMN比例及肺损伤评分在2、4和6h3个时间点均明显低于油酸组(均P＜0.05);肺组织中H2S含量在4和6h明显高于油酸组(均P＜0.05);肺泡上皮细胞中NF-κB核表达和ICAM-1胞膜表达在4和6h则明显低于油酸组相应时间点(均P＜0.05).结论 H2S可能通过抑制ALI大鼠肺部炎症反应发挥保护效应,其抗炎效应与其抑制大鼠肺泡上皮细胞NF-κB的表达有关.     

SIRT1激动剂通过降低ACAT1表达抑制平滑肌泡沫细胞形成

目的 探讨沉默信息调节因子1 (silent mating type information regulation 2 homolog-1,SIRT1)对氧化型低密度脂蛋白(oxidized low density lipoprotein,ox-LDL)诱导的血管平滑肌细胞(vascularsmooth muscle cell,VSMC)泡沫化的作用和相关的分子机制.方法 用组织贴块法体外培养原代VSMC,用80μg/mL ox-LDL刺激VSMC诱导泡沫细胞形成.检测SIRT1在ox-LDL刺激不同时间(24、48、72 h)的表达变化.SIRT1的活性调控分别应用SIRT1激动剂(SRT1720,SRT,1μmol/L)和抑制剂(nicotinamide,Nic,100 μmoL/L)进行干预.干预24 h后采用Western blot检测VSMC过氧化物酶体增殖物激活受体γ(peroxisome proliferator-activated receptorγ,PPARγ)、酰基辅酶A:胆固醇酰基转移酶1(A-cholesterol acyhransferase 1,ACAT1)的蛋白表达,干预48 h后采用油红O染色检测细胞内脂质沉积和泡沫细胞形成情况.应用PPARγ激动剂(Rosiglitazone,RSG,50 μmol/L)和抑制剂(GW9662,10 μmol/L)调控PPARγ的表达,Western blot检测VSMC中ACAT1的表达.结果 ①ox-LDL诱导的VSMC泡沫细胞中,SIRT1蛋白表达在48 h降低约47％ (P ＜0.01);油红O染色显示,SRT可以抑制VSMC泡沫细胞形成,而Nic可逆转SRT的抑制作用;②ox-LDL诱导的VSMC泡沫细胞中ACAT1的表达显著增加[(2.77±0.70),P＜0.01],SIRT1激动剂SRT可显著抑制ACAT1的表达[(0.90±0.27),P＜0.01],而SIRT1抑制剂Nic可阻断这一作用,升高ACAT1的表达[(2.25±0.37),P＜0.05];③ox-LDL诱导的VSMC泡沫细胞中PPARγ的表达减少[(0.73±0.12),P＜0.05],SIRT1激动剂SRT可上调VSMC中PPARγ的表达[(0.98±0.16),P＜0.05],SIRT1抑制剂Nic抑制PPARγ的表达[(0.47 ±0.13),P＜0.01];④PPARγγ激动剂RSG可抑制ACAT1的表达[(0.73±0.09),P＜0.01],而PPARγ抑制剂GW9662则上调ACAT1表达[(1.68±0.09),P＜0.01].结论 SIRT1通过上调VSMC中PPARγ表达而抑制ACAT1表达,从而抑制ox-LDL诱导的VSMC泡沫样变.     

热量限制通过AMPK-SIRT1-线粒体通路延缓小鼠骨骼肌衰老

目的 观察热量限制对老化进程中小鼠骨骼肌线粒体等生物学性状的影响,探讨热量限制生物效应的分子机制.方法 13月龄C57BL/6雄性小鼠30只,按照简单随机抽样法分为自由进食组和热量限制组,每周按照自由进食组前1周平均摄食量的60％饲养热量限制小鼠.热量限制12周后,测量骨骼肌衰减指数、胫前肌等肌纤维密度及相对横截面积,透射电镜观察骨骼肌线粒体变化,Western blot检测PGC1 α、AMPKα、p-AMPKα及SIRT1等的表达,并比较老年鼠与成年鼠的表达差异.结果 ①与自由进食组比较,热量限制组骨骼肌衰减指数变化不明显,胫前肌等肌纤维密度显著升高(P＜0.01),相对横截面积降低(P＜0.01);②电镜观察显示:与自由进食组比较,热量限制组骨骼肌线粒体长度和宽度均增加(P＜0.05,P＜0.01),相对密度增加(P＜0.01),PGC1α表达升高(P＜0.05);③与自由进食组比较,热量限制组骨骼肌AMPK的磷酸化水平升高(P＜0.01),同时SIRT1表达也升高(P＜0.05);④与成年鼠比较,老年鼠骨骼肌AMPK磷酸化水平下降(P＜0.05),SIRT1和PGC1α的表达也均下降(P＜0.05).结论 热量限制能显著促进老化进程中骨骼肌线粒体的生成及活性,这一作用可能通过激活AMPK信号途径实现.     

胰岛素对1-甲基-4-苯基吡啶离子诱导的嗜铬细胞瘤细胞损伤的保护

目的 观察胰岛素处理是否减轻1-甲基4-苯基吡啶离子(MPP+)诱导的嗜铬细胞瘤PC12细胞凋亡,探讨可能的机制.方法 测定不同处理后PC12细胞的存活和细胞凋亡情况,观察胰岛素处理对细胞内信号蛋白激酶B(Akt)、糖元合成酶激酶3β(GSK3β)和微管相关蛋白tau磷酸化的影响.结果 胰岛素处理能保护细胞,增加撤除血清后细胞的活力(P＜0.01);增强PC12细胞对100μmol/L MPP+毒性的耐受(P＜0.05),这一作用可以被Akt抑制剂--LY294002阻断.Hoechest染色和流式细胞检测显示,胰岛素干预减少细胞凋亡.100 nmol/L胰岛素处理细胞,Akt ser-473磷酸化程度升高(P＜0.01);GSK3βser-9磷酸化增强(P＜0.01).胰岛素干预,减少tau pS199过磷酸化,而不改变tan pT231的磷酸化.结论 胰岛素通过其细胞内信号通路,调节Akt/GSK3β的磷酸化,减轻MPP+诱导的PC12细胞凋亡.