睾酮对心脏老化过程中心肌纤维化的干预研究

目的观察睾酮对心脏老化过程中心肌纤维化的干预效应。方法差速贴壁法培养雄性昆明白乳鼠心肌成纤维细胞,并分为4组:A组(培养液)、B组(60 μmol/L H_2O_2)、C组(30 nmol/L 睾酮+B组)、D组(氟他胺1μmol/L+C组)。用β半乳糖苷酶染色检测细胞的阳性率,MTT法检测细胞增殖能力,流式细胞仪分析细胞周期,二氯荧光黄荧光显色检测细胞内活性氧(ROs)。α平滑肌肌动蛋白(α-SMA)免疫化学染色反应细胞的表型转化,RT-PCR法检测转化生长因子β1(TGF-β1)mRNA、P16 mRNA和cyclin D1 mRNA的表达。结果与A组比较.B组β-半乳糖苷酶染色阳性细胞增加,ROS水平增加,P16 mRNA、cyclin D1 mRNA、TGF-β1 mRNA表达上调,细胞增殖能力明显下降,G_0/G_1期细胞比例增多,同时α-SMA免疫组织化学染色出现明显强阳性;与B组比较,C组上述各项指标下降;与C组比较,D组能部分阻断睾酮的各种保护作用。结论睾酮通过受体机制干预氧化应激诱导的心肌成纤维细胞的衰老,这可能是睾酮抗心脏老化过程中心肌纤维化的机制之一。     

齐墩果酸对过氧化氢诱导血管平滑肌细胞凋亡的影响

目的研究齐墩果酸(OA)对H_2O_2诱导血管平滑肌细胞(VSMCs)凋亡的影响。方法采用贴块法培养大鼠主动脉VSMCs,随机分为对照组、H_2O_2组、H_2O_2+OA组、阻断剂组。采用Hoechst 33342染色和Annexin V/FITC染色检测各组细胞凋亡情况;Western blot检测各组细胞中磷酸化Akt蛋白表达变化。结果与对照组比较,H_2O_2组细胞凋亡率明显升高,p-Akt蛋白表达明显降低(P<0.05);与H_2O_2组比较,H_2O_2+OA组细胞凋亡率明显降低,p-Akt蛋白表达明显升高(P<0.05);与H_2O_2+OA组比较,阻断剂组细胞凋亡率明显升高,p-Akt蛋白表达明显降低(P<0.05)。荧光显微镜显示,对照组细胞核呈蓝色,H_2O_2组细胞核呈致密浓染,H_2O_2+OA组细胞核呈蓝染,有少量细胞核致密浓染,阻断剂组细胞核呈致密浓染。结论 OA能减轻H_2O_2导致的VSMCs凋亡,其机制可能与激活细胞内磷脂酰肌醇-3激酶/Akt信号通路引起下游促生存基因的表达有关。     

Melatonin protects SK-N-SH neuroblastoma cells from amphetamine-induced neurotoxicity

Several hypotheses regarding the mechanism underlying amphetamine-induced neurotoxicity have been proposed. One of them is based on the observation of free radical formation and oxidative stress produced by auto-oxidation of dopamine (DA). The formation of DA-related reactive oxygen species (ROS) such as superoxide and hydroxyl radicals appears to play an important role in amphetamine-induced neurotoxicity. Melatonin, the main secretory product of pineal gland, is well known for its protective effects that are currently attributed mainly to its radical scavenging and antioxidant properties. The present study was conducted to investigate the protective effects of melatonin on d-amphetamine (AMPH)-induced neurotoxicity in cultured human dopaminergic neuroblastoma SK-N-SH cells. Our data indicate that AMPH significantly reduces cell viability, induces oxidative stress (enhances ROS production and malondialdehyde levels), up-regulates alpha-synuclein expression and decreases intracellular ATP levels. However, pretreatment of SK-N-SH cells with melatonin prevents AMPH-induced loss of cell viability and induction of oxidative stress, while reducing alpha-synuclein expression and increasing ATP production. These results suggest that the antioxidant properties of melatonin may provide a protective mechanism against AMPH-induced neuronal degeneration.     

Melatonin-induced autophagy protects against human prion protein-mediated neurotoxicity

Melatonin has neuroprotective effects in the models of neurodegenerative disease including Alzheimer's and Parkinson's disease. Several studies have shown that melatonin prevents neurodegeneration by regulation of mitochondrial function. However, the protective action of melatonin has not been reported in prion disease. We investigated the influence of melatonin on prion-mediated neurotoxicity. Melatonin rescued neuronal cells from PrP(106-126)-induced neurotoxicity by prevention of mitochondrial dysfunction. Moreover, the protective effect of melatonin against mitochondrial dysfunction was related with autophagy activation. Melatonin-treated cells were dose-dependently increased in LC3-II, an autophagy marker. Melatonin-induced autophagy prevented a PrP(106-126)-induced reduction in mitochondrial potential and translocation of Bax to the mitochondria and cytochrome c release. On the other hand, downregulation of autophagy protein 5 with Atg5 siRNA or the autophagy blocker 3-methyladenine prevented the melatonin-mediated neuroprotective effects. This is the first report demonstrating that treatment with melatonin appears to protect against prion-mediated neurotoxicity and that the neuroprotection is induced by melatonin-mediated autophagy signals. The results of this study suggest that regulation of melatonin is a therapeutic strategy for prion peptide-induced apoptosis.     

下调NAD（P）H氧化酶4加重缺氧复氧心肌细胞损伤：线粒体SIRT3信号的关键作用

目的明确内源性NAD（P）H氧化酶4（Nox4）在心肌细胞缺氧／复氧（H／R）损伤中的作用并探讨其可能的机制。方法：以H,C2心肌细胞系为研究对象,建立H／R模型,将细胞分为对照组、NC-siRNA组、Nox4-siRNA组、H／R组、H／R＋NC-siRNA组和H／R＋Nox4-siRNA组。采用RNAi方法下调Nox4的表达,MTT比色法测定相对存活率、荧光素酶化学发光法测量ATP水平,MitoSOX荧光探针检测线粒体ROS,比色法测定NAD＋／NADH的比值,Western blot法测定Nox4和SIRT3表达水平。结果：与对照组相比,H／R组H。c,心肌细胞中Nox4蛋白的水平明显增加（P〈0．05）,相对存活率、ATP的水平明显降低（P〈0．05,P〈0．01）,而线粒体ROS生成明显增加（P〈0．01）,同时NAD＋／NADH的比值明显增加、SIRT3表达量明显降低（P〈0．05,P〈0．01）。与H／R组相比,H／R＋Nox4-siRNA组Nox4蛋白水平显著降低（P〈0．05）,相对存活率、ATP的水平进一步降低、线粒体ROS生成进一步增加（P〈0．05）,同时,NAD＋／NADH的比值明显降低（P〈0．01）、SIRT3蛋白水平进一步降低（P〈0．05）。结论：下调Nox4可加重H／R诱导的心肌细胞损伤和氧化应激,抑制线粒体能量生成,其心肌细胞保护机制可能是通过上调NAD＋／NADH的比值,增加SIRT3的表达而发挥作用。     

Protective effects of Taxifolin on H_2O_2-induced damage in H9C2 cells

Background Taxifolin(Tax) is an essential natural antioxidant. Multiple studies have shown that Tax can protect cardiomyocytes from ischemia-reperfusion injury. However, the underlying mechanism is still unclear.Methods H9C2 cells were randomly divided into control, H_2O_2 group, Tax pretreatment group(Tax + H_2O_2);Tax effect group. Cell activity was detected by CCK-8 and the intracellular structure was observed by transmission electron microscopy. Autophagy was determine by Western blotting analysis of Beclin-1, Bcl-2 and PKC.Results Tax pretreatment significantly increased anti-apoptotic protein Bcl-2 and autophagy protein Beclin-1.Expression of PKC was inhibited by Tax. Conclusions Tax pretreatment could protect H9 C2 cells against H_2O_2-induced damage through the Bcl-2 and autophagy pathways.     

H_2O_2体外抗棘阿米巴作用研究

目的检测H_2O_2的抗棘阿米巴(Acanthamoebaspp.)作用。方法自角膜炎患者角膜刮片分离获得棘阿米巴复合体(AcanthamoebaLugdunensis-Acanthamoebaquina)。于培养基(PYG)培养传代。实验前将棘阿米巴用新鲜的PYG培养1d使其活化,配成2.5×10~6/ml细胞悬液加入细胞培养板,实验组各孔分别加入不同浓度H_2O_2,对照组加等量PYG,28℃24h后实验组更换新鲜PYG继续培养3d。取细胞悬液滴片,瑞氏染色,观察细胞形态变化。用定量培养法作棘阿米巴生长曲线,观察其增殖速率。用四甲基偶氮唑盐(MTT)比色法,观察H_2O_2对棘阿米巴成活率的影响。用乳酸脱氢酶(LDH)测定法测定H_2O_2对棘阿米巴的损伤。结果棘阿米巴滋养体在0.125％H_2O_2作用下,不可逆转地成为包囊,20～120h增殖率为0;1％H_2O_2可使其破裂。结论H_2O_2具有较强的抗棘阿米巴作用,有可能成为预防棘阿米巴角膜炎的理想药物。     

过表达HSF1及ASK1基因对H2O2刺激后心肌细胞内ROS水平的影响

目的研究热休克因子1(HSF1)及凋亡信号调节激酶1(ASK1)对过氧化氢(H_2O_2)刺激后心肌细胞内活性氧簇水平(ROS)变化的影响。方法对不同组培养心肌细胞分别单独转染质粒HSF1,ASK1,及共转染HSF1 ASK1,48h待其充分表达后用1 mmol/LH_2O_2刺激心肌细胞30min,检测细胞内ROS水平,并与相应转染后未刺激组及未转染的对照组比较,观察ROS水平的变化。结果(1)所有H_2O_2刺激组心肌细胞内ROS水平均高于相同转染条件下的非刺激组(P<0.05);(2)相同H_2O_2刺激条件下,各组ROS水平:HSF1组低于对照组(P<0.05),ASK1组与对照组无显著差异,HSF1 ASK1组与单转HSF1组相比有升高的趋势;(3)相同H_2O_2刺激条件下,各组刺激后比刺激前ROS水平增高的幅度:HSF1组低于对照组(P<0.05),ASK1组与对照组无显著差别,HSF1 ASK1组与单转HSF1组相比有升高的趋势。结论在H_2O_2刺激条件下,HSF1可通过降低心肌细胞内的ROS水平来发挥细胞保护作用,而ASK1对细胞内ROS水平无影响,但其可干扰HSF1对ROS的抑制作用。     

Reactive Oxygen Species (ROS) Are Not a Key Determinant for Zika Virus-Induced Apoptosis in SH-SY5Y Neuroblastoma Cells

Introduction: ZIKV is a highly neurotropic virus that can cause the death of infected neuroprogenitor cells through mitochondrial damage and intrinsic apoptotic signaling. In this context, the role of reactive oxygen species (ROS) in neuronal cell death caused by ZIKV still remains elusive. Objective: We aimed at evaluating the role of these cellular components in the death of human undifferentiated neuroblastoma cell line infected with ZIKV. Results: ZIKV infection resulted in the extensive death of SH-SY5Y cells with the upregulation of several genes involved in survival and apoptotic responses as well as the colocalization of mitochondrial staining with ZIKV Envelope (E) protein. Notably, levels of intracellular reactive oxygen species (ROS) were not altered during ZIKV infection in undifferentiated SH-SY5Y cells, and consistent with these results, the treatment of infected cells with the widely studied ROS scavenger N-acetylcysteine (NAC) did not prevent cell death in these cells. Conclusion: Altogether, our results suggest that excessive ROS production is not the main trigger of SH-SY5Y cells death in ZIKV infection.     

参知健脑片组分对β淀粉样蛋白致SH—SY5Y细胞凋亡的保护作用

目的 为参知健脑片（SZJ）的临床应用奠定基础。方法 以参知健脑片组分作用于人神经母细胞瘤细胞株（SH—SY5Y）模型,用具有神经营养作用的APP17肽为对照药物。分组给药并培养24h,以倒置相差显微镜观察SH-SY5Y细胞形态;CCK-8法检测细胞存活率;用流式细胞仪定量分析细胞凋亡峰,以2’,7＇-二氢二氯荧光黄双乙酸钠（DCFH-DA）为标记探针检测细胞内活性氧水平。结果 参知健脑片处理细胞24h后,与其他各组比较,SH-SY5Y细胞存活率明显升高;细胞形态明显改变;凋亡率明显降低,细胞内活性氧水平明显降低,P均〈0．01。结论 参知健脑片能抑制SH-SY5Y细胞凋亡,其神经细胞保护作用可能与降低细胞内活性氧水平有关。     

Protective effects of ethyl gallate on H2O2-induced mitochondrial dysfunction in PC12 cells

Oxidative stress has been suggested to play an important role in neuronal injury. Ethyl gallate (EG) is the ethyl ester of gallic acid which has been acknowledged as an antioxidant. We previously demonstrated that EG effectively inhibited H₂O₂-induced cytotoxicity and decreased the ROS levels in PC12 cells, while the relevant mechanisms of action of this compound remain largely uncharacterized. The present study was carried out in an attempt to clarify the underlying mechanisms of EG against H₂O₂-induced neurotoxicity in PC12 cells. EG pretreatment attenuated H₂O₂-induced mitochondrial dysfunction as indicated by the decreased caspase-9/?3 activation, PARP cleavage, mitochondrial membrane potential (MMP) depletion, Bax/Bcl-2 ratio, cytochrome c release and ROS overproduction. Furthermore, EG treatment resulted in nuclear translocation of Nrf2 along with increased expression of ARE-dependent cytoprotective genes, such as γ-GCS and NQO1, which indicated EG as an Nrf2 pathway activator. Silencing of Nrf2 signaling by siRNA abrogated the protective effects offered by EG on H₂O₂-induced PC12 cells injury, which suggested the important role of Nrf2 pathway in the protection of EG against oxidative stress induced PC12 cell apoptosis. These results taken together indicated that EG protects PC12 cells against H₂O₂-induced cell mitochondrial dysfunction possibly through activation of Nrf2 pathway. EG might be a potential candidate for further preclinical study aimed at the prevention and treatment of neurodegenerative diseases.

     

Antiproliferative and apoptotic effects of Phyla nodiflora extracts on human breast cancer cell line

IntroductionCancer is a disease of gene disorder that occurs in the normal processes of cell division. Undesirable side effects of chemotherapy and surgery have triggered the search of new compounds from plant to fight cancer because they are relatively safer than synthetic drugs. Apoptosis is a process of internally programmed cell death, which is initiated by intrinsic or extrinsic signals. It plays important roles in cancer development and treatment, thus the ability of bioactive compounds to increase the sensitivity of cancerous cells towards cellular damage and activate the apoptotic response is the most desirable. Phylanodiflora has been used as folk medicine for various ailments. It is known to have various biological activities such as antioxidant, antimicrobial, antitumor, anti-inflammatory, antidiabetic, and hepatoprotective and antimelanogenesis effects but their underlying molecular events are largely unknown.ObjectiveTo study the antiproliferative and apoptosis activity of P.nodiflora in MCF7 cells.MethodsThe leaf and stem of this plant was extracted separately using methanol and ethyl acetate. The free radical scavenging activity of the plant extracts was determined using DPPH antioxidant assay, while the proliferation assay was performed using MTT method. DNA fragmentation induced by the plant extracts was evaluated through DNA extraction.Results & DiscussionCompared to stem extracts (1.2134 mg/ml and 0.9877 mg/ml for ethyl acetate and methanol respectively), both leaf extracts exhibited lower EC₅₀ values (0.4271 mg/ml and 0.6177 mg/ml for ethyl acetate and methanol respectively) which indicating higher antioxidant activity. MTT results showed that MCF7 cells were inhibited by all the extracts with IC₅₀ ranging from 90–120 μg/ml. DNA extracted from treated cells showed the formation of DNA laddering suggesting the occurrence of apoptosis.ConclusionThe results suggest that Phyla nodiflora extracts are capable of inhibiting cancer cell growth via apoptosis.     

纳米材料PEG-PEI介导双基因促体外拟神经细胞凋亡的作用

目的 探讨新型纳米材料PEG-PEI介导的双基因pIRES2-EGFP/CD-5-FC和pIRES2-EGFP/TRAIL在体外对拟神经细胞模型(神经母细胞瘤株SH-SY5Y细胞)的联合杀伤作用.方法 将PEG-PEI介导的联合基因pIRES2-EGFP/CD-5-FC和pIRES2-EGFP/TRAIL转染SH-SY5Y细胞后,采用MTT法观察其对SH-SY5Y细胞的杀伤作用,荧光显微镜下观测以及流式细胞仪检测SH-SY5Y细胞凋亡率及FPEG-PEI的转染效率.结果 N/P=15时PEG-PEI转染两种目的基因中单一基因的细胞凋亡作用最强(P＜0.01);两种基因联合转染SH-SY5Y细胞时的细胞凋亡率为77％,较单一基因转染的细胞凋亡率提高了27％ (P ＜0.01).结论 CD-5 -FC和TRAIL基因在体外联合转染对SH-SY5Y细胞的杀伤作用较单一基因更强;PEG-PEI可以作为神经细胞基因靶向传输的载体行神经系统疾病基因治疗的体内实验研究.     

Melatonin reduces induction of Bax, caspase and cell death in methamphetamine-treated human neuroblastoma SH-SY5Y cultured cells

Abstract:  Several studies demonstrated that methamphetamine (MA)-treated human neuroblastoma cells exhibit increased oxidative stress, which regulates intracellular signaling cascades leading to cell death. Melatonin has a potential as a direct free radical scavenger and protects against cell death caused by MA. The objective of this study was to investigate the neuroprotective properties of melatonin on MA-induced induction of death signaling cascade and neuronal cell degeneration in human neuroblastoma SH-SY5Y cultured cells. The results of the present study demonstrate that MA significantly reduced cell viability in SH-SY5Y cultured cells. Desipramine, a monoamine uptake blocker, and melatonin reversed the toxic effect of MA in reducing cell viability. Induction of Bax, Bcl-2 and cleaved caspase-3 protein levels were observed in SH-SY5Y cultured cells treated with MA, whereas the induction of Bax and cleaved caspase-3 was diminished by melatonin. Visualization of the induction of Bax using immunofluorescence but a reduction in mitochondrial sites using red-fluorescent mitochondria-staining dye was more obviously apparent in MA-treated cells than in untreated control cells and, again, this effect was abolished by melatonin. These findings demonstrate important roles of Bax and caspase in death signaling cascade, and the protective effects of melatonin in MA-treated SH-SY5Y cells.     

促红细胞生成素对过氧化氢损伤后大鼠骨骼肌卫星细胞凋亡和钙离子浓度的影响

目的 探讨过氧化氢(H_2O_2)对大鼠骨骼肌卫星细胞(skeletal muscle satellite cell,SMSC)凋亡和细胞内钙离子浓度的影响及促红细胞生成素(EPO)的保护作用.方法 取体外培养的SMSC,随机分为对照组、H_2O_2组和EPO干预组及EPO+H_2O_2组,采用流式细胞仪检测细胞凋亡率和钙离子浓度的平均荧光强度,Hoechst33258染色后荧光显微镜观察凋亡细胞的形态学变化.结果 H_2O_2组凋亡发生率最高,为(22.13±1.79)%,经10、20、40 U/ml的EPO预处理后凋亡率分别为(16.47±2.53)%、(4.97±0.55)%、(2.93±0.47)%,对照组凋亡率为(1.93±0.57)%;检测细胞内钙离子荧光强度结果显示,经10、20、40 U/ml浓度的EPO预处理后分别为(12.67±0.32)、(27.90±0.66)、(44.53±0.93),与H_2O_2组(9.70±0.09)及对照组(51.37±0.64)比较,差异有统计学意义(P<0.05);H_2O_2组和低剂量EPO干预组(10 U/ml、20 U/m1),Hoechst33258染色呈明显的凋亡征象,而高剂量EPO干预组(40 U/m1)和对照组则较少见凋亡细胞.结论 EPO可抑制H_2O_2诱导的细胞凋亡和减少钙离子的释放,且呈剂量相关性.     

Protection against cell death and sustained tyrosine hydroxylase phosphorylation in hydrogen peroxide- and MPP+-treated human neuroblastoma cells with melatonin

Abstract:  Neuroprotective effects of melatonin against oxidative stress-induced neuronal cell degeneration in human SH-SY5Y neuroblastoma cells were investigated in this report. The results demonstrate that exogenous administration of H₂O₂ and 1-methyl, 4-phenyl, pyridinium ion (MPP⁺) significantly decreased cell viability in SH-SY5Y cultured cells. Desipramine, a monoamine uptake blocker was able to abolish the toxic effects of MPP⁺ but not H₂O₂ in reduction of cell viability. Conversely, melatonin reversed the toxic effects of H₂O₂ and MPP⁺ on cell viability. In addition, the reduction of phosphorylation of tyrosine hydroxylase, the rate limiting enzyme in dopamine synthesis, and phosphorylation of cyclic AMP responsive element-binding protein by H₂O₂ and MPP⁺ was also diminished by melatonin. These results demonstrate some effective roles of melatonin on neuroprotection and its action on the modulation of tyrosine hydroxylase phosphorylation.     

Decreased intracellular calcium mediates the histamine H3-receptor-induced attenuation of norepinephrine exocytosis from cardiac sympathetic nerve endings

Activation of presynatic histamine H(3) receptors (H(3)R) down-regulates norepinephrine exocytosis from cardiac sympathetic nerve terminals, in both normal and ischemic conditions. Analogous to the effects of alpha(2)-adrenoceptors, which also act prejunctionally to inhibit norepinephrine release, H(3)R-mediated antiexocytotic effects could result from a decreased Ca(2+) influx into nerve endings. We tested this hypothesis in sympathetic nerve terminals isolated from guinea pig heart (cardiac synaptosomes) and in a model human neuronal cell line (SH-SY5Y), which we stably transfected with human H(3)R cDNA (SH-SY5Y-H(3)). We found that reducing Ca(2+) influx in response to membrane depolarization by inhibiting N-type Ca(2+) channels with omega-conotoxin (omega-CTX) greatly attenuated the exocytosis of [(3)H]norepinephrine from both SH-SY5Y and SH-SY5Y-H(3) cells, as well as the exocytosis of endogenous norepinephrine from cardiac synaptosomes. Similar to omega-CTX, activation of H(3)R with the selective H(3)R-agonist imetit also reduced both the rise in intracellular Ca(2+) concentration (Ca(i)) and norepinephrine exocytosis in response to membrane depolarization. The selective H(3)R antagonist thioperamide prevented this effect of imetit. In the parent SH-SY5Y cells lacking H(3)R, imetit affected neither the rise in Ca(i) nor [(3)H]norepinephrine exocytosis, demonstrating that the presence of H(3)R is a prerequisite for a decrease in Ca(i) in response to imetit and that H(3)R activation modulates norepinephrine exocytosis by limiting the magnitude of the increase in Ca(i). Inasmuch as excessive norepinephrine exocytosis is a leading cause of cardiac dysfunction and arrhythmias during acute myocardial ischemia, attenuation of norepinephrine release by H(3)R agonists may offer a novel therapeutic approach to this condition.     

7-二氟甲氧基金雀异黄素对H_2O_2诱导血管内皮细胞与单核细胞黏附的抑制作用

目的 探讨7-二氟甲氧基金雀异黄素对氧化应激诱导血管内皮细胞与单核细胞黏附的抑制作用及其机制.方法 荧光分光光度计检测单核细胞与血管内皮细胞的黏附,酶联免疫吸附法检测E选择素和细胞间黏附分子1等黏附分子的释放,Western blotting检测P38丝裂原活化蛋白激酶的磷酸化水平.结果 H2O2处理血管内皮细胞24 h后,内皮细胞-单核细胞的黏附率显著增加,内皮细胞E选择素和细胞间黏附分子1的释放增加;加入7-二氟甲氧基金雀异黄素后,血管内皮细胞-单核细胞的黏附率以及内皮细胞释放E选择素和细胞间黏附分子1等黏附分子呈浓度依赖性减少.H2O2处理血管内皮细胞24 h后,可显著激活P38丝裂原活化蛋白激酶,这一作用可被7-二氟甲氧基金雀异黄素所抑制.给予P38丝裂原活化蛋白激酶特异性抑制荆SB203580亦可阻断H2O2诱导的内皮细胞-单核细胞黏附及内皮细胞E选择素和细胞间黏附分子1的释放.结论 7-二氟甲氧基金雀异黄素对氧化应激诱导的血管内皮细胞与单核细胞黏附具有拮抗作用,其机制可能与其抑制P38丝裂原活化蛋白激酶的激活进而阻断内皮细胞释放黏附分子E选择素和细胞间黏附分子1有关.     

氧自由基降低脂肪细胞脂联素表达的机制研究

目的 研究活性氧簇(ROS)对3T3-LI脂肪细胞脂联素表达的调节机制.方法 以实时定量PCR检测分化成熟的3T3-L1脂肪细胞脂联素mRNA表达水平,联合应用多重磷酸化蛋白分析系统与各种蛋白激酶抑制剂,筛查ROS下调脂联索表达的信号通路.结果 作为一种重要的ROS,H_2O_2激活了313-L1脂肪细胞细胞外信号调节激酶1/2(ERK1/2)、c-Jun氨基端激酶(JNK)、蛋白激酶B(Akt)、p70 S6 激酶(p70 S6K)及Janus激酶/信号转导和转录激活因子(JAK/STAT)等多种信号转导通路.其中Akt和JAK/STAT抑制剂完全逆转H_2_O2对脂联素表达的下调作用(均P<0.01).结论 ROS可能通过激活Akt、JAK/STAT信号途径下调脂肪细胞脂联素的表达,从而在肥胖及其相关疾病的发生、发展中发挥作用.