曲格列酮对大鼠肝细胞氧化性损伤的研究

目的:研究曲格列酮的肝细胞毒性及其可能的机制.方法:在原代大鼠肝细胞模型和其他3种不同来源非肝细胞系,用WST-1法、乳酸脱氢酶释放法、荧光检测法、生物发光法等方法,观察曲格列酮对肝细胞的损伤作用.结果:不同剂量曲格列酮作用后,其在原代培养大鼠肝细胞的IC50值最低,即其对原代肝细胞毒性最大.曲格列酮诱导活性氧(ROS)生成,并引起还原型谷胱甘肽(GSH)和ATP水平比对照细胞显著降低.不同剂量的曲格列酮作用5h后诱发肝细胞凋亡、坏死.结论:曲格列酮对大鼠肝细胞的毒性作用强于对其他非肝细胞来源细胞的毒性作用.曲格列酮可以引起肝细胞氧化性损伤,肝细胞凋亡和坏死.     

抗糖尿病药曲格列酮的研究近况

介绍新一代噻唑烷－２,４－二酮类治疗Ⅱ型糖尿病的第一个新药曲格列酮。着重对曲格列酮的药效学、临床治疗以及毒副作用等方面作简要综述。曲格列酮对非胰岛素依赖性糖尿病具有独特的药效,该药可提高胰岛素的作用,不刺激胰岛素分泌,降低血糖,但不引起低血糖不增加体重。     

吡格列酮与曲格列酮影响肝癌细胞株SMMC-7721生长侵袭的实验研究

目的:探讨曲格列酮、吡格列酮对于肝癌细胞株SMMC-7721的生长、侵袭的影响.方法:采用四唑氮蓝还原法(MTT法)研究曲格列酮、吡格列酮对于肝癌细胞株的生长影响;细胞侵袭试验研究不同浓度的吡格列酮、曲格列酮对肝癌细胞株侵袭能力的影响.结果:MTT法及细胞侵袭试验可以发现不同浓度的曲格列酮、吡格列酮对肝癌细胞株生物学作用有影响.结论:曲格列酮、吡格列酮对于肝癌细胞株SMMC-7721生长、侵袭有明显的抑制作用.     

曲格列酮对白血病NB4细胞的增殖抑制作用及其作用机制

目的:探讨过氧化物酶体增殖物激活受体γ(PPARγ)激动剂曲格列酮(troglitazone,TGZ)对白血病NB4细胞的增殖抑制作用及其作用机制。方法:以不同浓度的TGZ(0～80μmol/L)作用于体外培养的NB4细胞0、24、48、72h,应用MTT法检测细胞生长抑制率,Hoechst33258染色法检测细胞凋亡,琼脂糖凝胶电泳观察细胞凋亡时的DNA梯状条带。用免疫印迹法(Western Blot)检测Caspase-3及其裂解底物多聚(ADP-核糖)聚合酶PARP[(poly(ADP-ribose)polymerase)]表达水平的变化,并对凋亡调节蛋白Bax及Bcl-2的表达水平进行检测。结果:20μmol/L以上的TGZ可显著抑制细胞的生长,在Hoechst染色后可见典型的细胞凋亡现象,并呈现出明显的量-效与时-效关系,药物作用72h后在琼脂糖凝胶电泳上可见明显的DNA梯状条带。WesternBlot检测结果表明,Caspase-3被活化出现20000的亚单位,同时PARP被裂解出现89000的亚单位片段。药物作用48h后凋亡抑制蛋白Bcl-2的表达水平明显降低,而促凋亡蛋白Bax的表达水平显著升...     

曲格列酮抑制甲状腺滤泡状癌细胞生长

目的 研究曲格列酮对甲状腺滤泡状癌细胞FTC-133生长的影响.方法 将甲状腺滤泡状癌细胞FTC-133与不同浓度的曲格列酮共培养,4-甲基偶氮四唑蓝( MTT)法观察其对FTC-133细胞增殖的影响,流式细胞仪DNA定量法分析曲格列酮对FTC-133细胞细胞周期的影响,半定量RT-PCR法测定曲格列酮对甲状腺滤泡状癌细胞p27 mRNA表达的影响.结果 曲格列酮可以抑制FTC-133细胞的增殖,并具有时间和浓度依赖性(P＜0.05);曲格列酮作用后,甲状腺滤泡状癌细胞FTC-133的G0/G1细胞的比例增加(P＜0.05);p27mRNA的表达显著升高(P＜0.05).结论 曲格列酮可以抑制甲状腺滤泡状癌细胞从G1期向S期的转化,从而抑制其增殖,曲格列酮可能成为治疗甲状腺滤泡状癌的一种选择.     

曲格列酮——新一代口服降糖药

本文综述治疗Ⅱ型糖尿病的新药曲格列酮的药理作用、药物动力学以及在糖尿病治疗上的应用     

环孢素A调节自噬对人滋养细胞氧化应激损伤的影响

目的探讨环孢素A(CsA)调节自噬对人滋养细胞氧化应激损伤的保护作用。方法将细胞分为对照组、氧化应激组、低剂量CsA(2μmol/L)组和高剂量CsA(4μmol/L)组。流式细胞仪检测HTR-8/SVneo滋养细胞凋亡,硫代巴比妥酸比色法检测丙二醛(MDA),化学比色法检测超氧化物歧化酶(SOD),化学荧光法检测活性氧(ROS),Western blot检测蛋白表达。结果对照组、氧化应激组、低剂量CsA组和高剂量CsA组HTR-8/SVneo细胞凋亡率分别为4.24%±0.72%、38.15%±4.63%、27.24%±3.16%、18.45%±2.28%,各组间比较差异有统计学意义(P<0.01)。CsA组细胞MDA和ROS显著低于氧化应激组(P<0.01),且高剂量CsA组低于低剂量CsA组(P<0.01);CsA组细胞SOD显著高于氧化应激组(P<0.01),且高剂量CsA组高于低剂量CsA组(P<0.01)。对照组、氧化应激组、低剂量CsA组和高剂量CsA组HTR-8/SVneo细胞自噬蛋白LC3Ⅱ表达的相对灰度值分别为0.23±0.05、0.11±0.02、0.38±0.07、0.75±0.13,各组间比较差异有统计学意义(P<0.01)。结论CsA可以增强滋养细胞自噬,对氧化应激损伤诱发的滋养细胞凋亡起到抑制作用。     

过氧化氢诱导心肌细胞氧化应激中心肌蛋白变化规律的研究

目的探讨过氧化氢(H2O2)诱导心肌细胞氧化应激中心肌蛋白的变化规律。方法采用原代分离小鼠心肌细胞,H2O2刺激心肌细胞,分别于不同浓度H2O2刺激不同时段后,采用MTT法分析细胞活力变化,流式细胞仪测定细胞凋亡情况,ELISA试剂盒测定细胞内GSH和MDA水平,并采用蛋白印迹方法测定心肌细胞内心肌蛋白心肌肌钙蛋白T(cTnT)和间隙连接蛋白43(connexin 43)的变化规律。结果高浓度H2O2较低浓度降低心肌细胞细胞活力显著,H2O2刺激2h后细胞活力降低显著(P<0.05);高浓度H2O2刺激2h后细胞凋亡率显著升高(P<0.05);H2O2刺激减少心肌细胞谷胱甘肽(GSH)水平,增加丙二醛(MDA)含量(P<0.05);H2O2刺激增加心肌细胞内cTnT和connexin 43蛋白表达,呈现一定量效关系。结论 H2O2刺激心肌细胞,可抑制心肌细胞活力,促进细胞凋亡,造成心肌细胞氧化应激损伤,H2O2引起心肌细胞内cTnT和connexin 43表达代偿增高。提示减少氧化应激,提高抗氧自由基防御机制与疾病转归密切相关。     

开放线粒体KATP通道对心肌细胞氧化应激损伤的保护作用

目的观察ATP敏感性钾通道(KATP)开放剂二氮嗪对心肌细胞氧化应激损伤的保护作用,并探讨其作用机制.方法采用过氧化氢(500 μmol·L-1)诱导法制备大鼠培养心肌细胞氧化应激损伤模型,通过检测培养液中乳酸脱氢酶以及用流式细胞仪结合罗丹明-123和碘化丙啶双标记法检测线粒体膜电位和细胞存活状态,观察二氮嗪(100 μmol·L-1)对氧化应激损伤的保护作用.结果二氮嗪预处理后,细胞培养液中乳酸脱氢酶活性较过氧化氢处理组显著降低(P＜0.01),细胞存活率升高,并可减少氧化应激造成的线粒体膜电位的丢失,其作用可被线粒体KATP通道阻断剂5-羟基癸酸酯所拮抗.结论二氮嗪对过氧化氢造成的培养心肌细胞氧化应激损伤具有保护作用,其可能通过激活线粒体KATP通道介导.     

高糖微环境对体外心肌细胞增殖活性和氧化应激的影响

目的：考察不同浓度葡萄糖对体外心肌细胞增殖活性和氧化应激的影响,探讨糖毒性对心肌细胞的损伤作用及可能的作用机制。方法：将含有不同浓度葡萄糖培养基处理的心肌细胞分别培养24,48,72 h,利用倒置显微镜观察心肌细胞形态学变化,MTT法检测心肌细胞活性,酶标法检测还原型谷胱甘肽（glutathione,GSH）、丙二醛（malondialdehyde,MDA）含量,四唑盐（water-soluble tetrazolium,WST-1）法检测超氧化物歧化酶（superoxide dismutase,SOD）活力,流式细胞法检测活性氧（reactive oxygen species,ROS）水平。结果：高浓度葡萄糖（33.30,50.00,100.00 mmol·L^-1）作用下,心肌细胞形态发生改变。与同期对照组及正常糖浓度组比较,高浓度葡萄糖作用24~72 h后,细胞增殖活性显著降低（P<0.05）。随着葡萄糖浓度增加和作用时间延长,细胞内GSH含量、SOD活力降低,MDA含量和ROS水平升高。结论：高浓度葡萄糖抑制心肌细胞增殖活性,诱导氧化应激反应发生,并通过破坏机体ROS与抗氧化物质之间的平衡,引起心肌细胞损伤。     

大蒜素对慢性铁中毒大鼠氧化应激与肝细胞自噬的抑制作用

目的探讨大蒜素(allicin)对慢性铁中毒大鼠氧化应激与肝细胞自噬的抑制作用及可能机制。方法 36只SD大鼠按体质量随机分为6组,即正常对照(饲喂基础饲料)、慢性铁中毒模型(饲喂高铁饲料)、正常+大蒜素40 mg·kg-1、慢性铁中毒+大蒜素30,40和60 mg·kg-1组,每组6只。持续饲喂6周后,取血及肝、结肠和肾组织用试剂盒测定铁含量、总铁结合力、丙二醛(MDA)含量及总超氧化物歧化酶(T-SOD)活性。透射电镜和免疫组织化学方法观察肝细胞形态结构、自噬以及胱天蛋白酶3凋亡蛋白、Ki-67细胞增殖抗原和LC3-B微管相关蛋白表达的变化。结果与正常对照组比较,模型组血清铁含量增加(P<0.01),总铁结合力下降(P<0.01),肝和结肠组织铁含量增加(P<0.05)。与模型组比较,饲喂不同剂量大蒜素大鼠血清铁含量显著下降(P<0.05),总铁结合力显著增加(P<0.05),结肠组织铁含量显著下降(P<0.05);饲喂大蒜素40和60 mg·kg-1肝组织铁含量显著下降(P<0.05)。与正常对照组比较,模型组肝和结肠组织MDA含量显著增加(P<0.05),肝组织T-SOD活性增加(P<0.01),结肠组织T-SOD活性下降(P<0.01)。与模型组比较,饲喂大蒜素组肝组织MDA含量显著下降(P<0.05),结肠和肾组织T-SOD活性显著增加(P<0.05)。与正常对照组比较,模型组肝实质细胞和肝非实质细胞Ki-67增殖抗原表达显著增加(P<0.05),胱天蛋白酶3凋亡蛋白表达无明显变化(P>0.05)。观察肝细胞超微结构,模型组大鼠肝细胞有大量铁蛋白颗粒累积,线粒体和内质网膜膨胀,胞质中形成自噬前体。模型组大鼠肝细胞LC3-B微管相关蛋白有较强表达,正常对照和正常+大蒜素组肝细胞未发现LC3-B免疫阳性染色。结论大蒜素能有效清除体内自由基,增强机体抗氧化能力,降低肝中铁诱导的氧化压力、线粒体膜的改变和细胞自噬,对慢性铁中毒肝细胞具有一定的保护作用。     

Smog induces oxidative stress and microbiota disruption

Smog is created through the interactions between pollutants in the air, fog, and sunlight. Air pollutants, such as carbon monoxide, heavy metals, nitrogen oxides, ozone, sulfur dioxide, volatile organic vapors, and particulate matters, can induce oxidative stress in human directly or indirectly through the formation of reactive oxygen species. The outermost boundary of human skin and mucous layers are covered by a complex network of human-associated microbes. The relation between these microbial communities and their human host are mostly mutualistic. These microbes not only provide nutrients, vitamins, and protection against other pathogens, they also influence human's physical, immunological, nutritional, and mental developments. Elements in smog can induce oxidative stress to these microbes, leading to community collapse. Disruption of these mutualistic microbiota may introduce unexpected health risks, especially among the newborns and young children. Besides reducing the burning of fossil fuels as the ultimate solution of smog formation, advanced methods by using various physical, chemical, and biological means to reduce sulfur and nitrogen contains in fossil fuels could lower smog formation. Additionally, information on microbiota disruption, based on functional genomics, culturomics, and general ecological principles, should be included in the risk assessment of prolonged smog exposure to the health of human populations.     

Schisandra chinensis essential oil attenuates acetaminophen-induced liver injury through alleviating oxidative stress and activating autophagy

ContextSchisandra chinensis (Turcz.) Baill. (Magnoliaceae) essential oil (SCEO) composition is rich in lignans that are believed to perform protective effects in the liver.ObjectiveThis study investigates the effects of SCEO in the treatment of acetaminophen (APAP)-induced liver injury in mice.Materials and methodsC57BL/6 mice (n = 56) were randomly divided into seven groups: normal; APAP (300 mg/kg); APAP plus bicyclol (200 mg/kg); APAP plus SCEO (0.25, 0.5, 1, 2 g/kg). Serum biochemical parameters for liver function, inflammatory factors, and antioxidant activities were determined. The protein expression levels of Nrf2, GCLC, GCLM, HO-1, p62, and LC3 were assessed by western blotting. Nrf2, GCLC, HO-1, p62, and LC3 mRNA were detected by real-time PCR.ResultsCompared to APAP overdose, SCEO (2 g/kg) pre-treatment reduced the serum levels of AST (79.4%), ALT (84.6%), TNF-α (57.3%), and IL-6 (53.0%). In addition, SCEO (2 g/kg) markedly suppressed cytochrome P450 2E1 (CYP2E1) (15.4%) and attenuated the exhaustion of GSH (43.6%) and SOD (16.8%), and the accumulation of MDA (22.6%) in the liver, to inhibit the occurrence of oxidative stress. Moreover, hepatic tissues from our experiment revealed that SCEO pre-treatment mitigated liver injury caused by oxidative stress by increasing Nrf2, HO-1, and GCL. Additionally, SCEO activated autophagy, which upregulated hepatic LC3-II and decreased p62 in APAP overdose mice (p < 0.05).Discussion and conclusionsOur evidence demonstrated that SCEO protects hepatocytes from APAP-induced liver injury in vivo and the findings will provide a reliable theoretical basis for developing novel therapeutics.     

Methamidophos induces cytotoxicity and oxidative stress in human peripheral blood mononuclear cells

Previous studies have shown that organophosphate pesticide (OP) exposure is associated with oxidative stress. Methamidophos (MET) is an OP widely used in agriculture, which is regarded as a highly toxic pesticide and it is a potent inhibitor of acetylcholinesterase. The aim of this study was to evaluate whether MET can induce oxidative stress at low concentrations in primary cultures of human peripheral blood mononuclear cells (PBMCs). PBMCs from healthy individuals were exposed to MET (0–80 mg/L) for 0–72 h. We performed the MTT and neutral‐red assays to assess the cytotoxicity. As indicators of oxidative stress, the levels of reactive oxygen species (ROS) were assessed using flow cytometry, and the malondialdehyde (MDA) and reduced glutathione (GSH) levels were determined. MET decreased the viability of PBMCs in a dose‐dependent manner. At concentrations of 3, 10, or 20 mg/L for 24 h, MET increased the ROS production significantly compared with the vehicle control. Similarly, MET increased the levels of MDA at the same concentrations that increased ROS (10 and 20 mg/L); however, no changes in GSH levels were observed. These results suggest that MET increased the generation of oxidative stress in PBMCs. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 147–155, 2017.     

Potassium bromate causes cell lysis and induces oxidative stress in human erythrocytes

In the present study, we have studied the effect of KBrO₃ on human erythrocytes under in vitro conditions. Erythrocytes were isolated from the blood of healthy nonsmoking volunteers and incubated with different concentrations of KBrO₃ at 37°C for 60 min. This resulted in marked hemolysis in a KBrO₃‐concentration dependent manner. Lysates were prepared from KBrO₃‐treated and control erythrocytes and assayed for various parameters. KBrO₃ treatment caused significant increase in protein oxidation, lipid peroxidation, hydrogen peroxide levels, and decrease in total sulfhydryl content, which indicates induction of oxidative stress in human erythrocytes. Methemoglobin levels and methemoglobin reductase activity were significantly increased while the total antioxidant power of lysates was greatly reduced upon KBrO₃ treatment. Intracellular production of reactive oxygen species increased in a dose dependent manner. Exposure of erythrocytes to KBrO₃ also caused decrease in the activities of catalase, glutathione peroxidase, thioredoxin reductase, glucose 6‐phosphate dehydrogenase and glutathione reductase whereas the activities of Cu‐Zn superoxide dismutase and glutathione‐S‐transferase were increased. These results show that KBrO₃ induces oxidative stress in human erythrocytes through the generation of reactive oxygen species and alters the cellular antioxidant defense system. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 138–145, 2014.     

Intraperitoneal glycerol induces oxidative stress in rat kidney

1. Glycerol has been used for the treatment of intracranial hypertension, cerebral oedema and glaucoma. Experimentally, intramuscular administration of hypertonic glycerol solution is used to produce acute renal failure. In this model, glycerol causes rhabdomyolysis and myoglobinuria, resulting in the development of renal injury. The pathogenesis is thought to involve vascular congestion, the formation of casts and oxidative stress. However, the effect of glycerol itself independent of rhabdomyolysis has not been investigated. Therefore, the aim of the present study was to investigate the effects of i.p. glycerol on some biochemical and oxidative stress parameters in the kidney of young rats. 2. Rats received 10 mL/kg, i.p., hypertonic glycerol solution (50% v/v) or saline (NaCl 0.85 g%) followed by 24 h water deprivation. Twenty-four hours after the administration of glycerol, rats were killed. Creatinine levels and the activity of creatine kinase (CK) and lactate dehydrogenase (LDH) were determined in the plasma. In addition, CK, pyruvate kinase and LDH activity and oxidative stress parameters (free radical formation, lipid peroxidation and protein carbonylation) were measured in renal tissue. 3. Glycerol did not alter plasma CK activity and increased plasma creatinine levels, suggesting renal insufficiency and the absence of rhabdomyolysis. Renal CK and pyruvate kinase activity was decreased, suggesting diminution of energy homeostasis in the kidney. Plasma and renal LDH activity was decreased, whereas the formation of free radicals, lipid peroxidation and protein carbonylation were increased, suggesting oxidative stress. 4. These results are similar to those described after the intramuscular administration of glycerol. Therefore, it is possible that glycerol may provoke renal lesions by mechanisms other than those induced by rhabdomyolysis.     

Arsenic: toxicity, oxidative stress and human disease

Arsenic (As) is a toxic metalloid element that is present in air, water and soil. Inorganic arsenic tends to be more toxic than organic arsenic. Examples of methylated organic arsenicals include monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. Reactive oxygen species (ROS)‐mediated oxidative damage is a common denominator in arsenic pathogenesis. In addition, arsenic induces morphological changes in the integrity of mitochondria. Cascade mechanisms of free radical formation derived from the superoxide radical, combined with glutathione‐depleting agents, increase the sensitivity of cells to arsenic toxicity. When both humans and animals are exposed to arsenic, they experience an increased formation of ROS/RNS, including peroxyl radicals (ROO^?), the superoxide radical, singlet oxygen, hydroxyl radical (OH^?) via the Fenton reaction, hydrogen peroxide, the dimethylarsenic radical, the dimethylarsenic peroxyl radical and/or oxidant‐induced DNA damage. Arsenic induces the formation of oxidized lipids which in turn generate several bioactive molecules (ROS, peroxides and isoprostanes), of which aldehydes [malondialdehyde (MDA) and 4‐hydroxy‐nonenal (HNE)] are the major end products. This review discusses aspects of chronic and acute exposures of arsenic in the etiology of cancer, cardiovascular disease (hypertension and atherosclerosis), neurological disorders, gastrointestinal disturbances, liver disease and renal disease, reproductive health effects, dermal changes and other health disorders. The role of antioxidant defence systems against arsenic toxicity is also discussed. Consideration is given to the role of vitamin C (ascorbic acid), vitamin E (α‐tocopherol), curcumin, glutathione and antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase in their protective roles against arsenic‐induced oxidative stress. Copyright © 2011 John Wiley & Sons, Ltd.     

Pyocyanin induces systemic oxidative stress,inflammation and behavioral changes in vivo

Pyocyanin (PCN) is a virulence factor secreted by Pseudomonas aeruginosa (P. aeruginosa) that has been shown to have numerous toxic effects in both in vitro and in vivo studies. Such toxicities include pro-inflammatory and pro-oxidant mediated responses. It is hypothesized that PCN can cross biological membranes and reach the systemic circulation, but no previous studies have investigated this. The aim of this study was, therefore, to quantify PCN in plasma and assess if systemic responses were occurring after localized intranasal administration in C57BL/6?J mice. This was achieved through the plasma quantification of PCN and assessment of changes to behavior using two commonly used tests, the forced swimming test and the open field test. Furthermore, evidence of systemic oxidative stress and inflammation was measured using malondialdehyde (MDA) and TNF-α post PCN exposure. PCN was found to cross into systemic circulation but in a variable manner. Furthermore, significant increases in plasma TNF-α and MDA (both p?相似文献   

Curcumin decreases oxidative stress in mitochondria isolated from liver and kidneys of high-fat diet-induced obese mice

Oxidative stress plays a key role in obesity and diabetes-related mitochondrial dysfunction. Mitochondrial dysfunction is characterized by increased oxidative damage, nitric oxide (NO) synthesis, and a reduced ratio of adenosine-5'-triphosphate (ATP) production/oxygen consumption. Curcumin represents a potential antioxidant and anti-inflammatory agent. In this study, our objective was to determine the effect of curcumin treatment on oxidative stress and mitochondrial dysfunction in high-fat diet (HFD)-induced obese mice (OM). These results suggest that curcumin treatment increased oxygen consumption and significantly decreased lipid and protein oxidation levels in liver mitochondria isolated from HFD-induced OM compared with those in the untreated OM (UOM). In kidney mitochondria, curcumin treatment significantly increased oxygen consumption and decreased lipid and protein peroxidation levels in HFD-induced OM when compared with those in UOM. Curcumin treatment neither has any effect on body weight gain nor have any effects on mitochondrial NO synthesis. These findings suggest that obesity induces oxidative stress and mitochondrial dysfunction, whereas curcumin may have a protective role against obesity-induced oxidative stress and mitochondrial dysfunction.