MAPK信号通路对蟾蜍灵抑制Jurkat细胞增殖及诱导其凋亡的影响

目的研究丝裂原活化蛋白激酶(MAPK)信号通路对蟾蜍灵(Bufalin)抑制急性淋巴细胞白血病Jurkat细胞增殖及诱导细胞凋亡的影响,初步探讨MAPK在蟾蜍灵治疗急性淋巴细胞白血病中的作用。方法WST-1法检测细胞的增殖活力,流式细胞术分析细胞凋亡。结果蟾蜍灵作用Jurkat细胞48 h,抑制细胞增殖50%的药物浓度(IC50)为44 nmol/L;5 nmol/L及以上蟾蜍灵以剂量依赖方式抑制Jurkat细胞增殖;20 nmol/L蟾蜍灵分别联合PD98059、SP600125,可显著增加对Jurkat细胞增殖的抑制,促进细胞凋亡;20 nmol/L蟾蜍灵联合SB203580作用于Jurkat细胞,可显著减少对Jurkat细胞增殖的抑制但对其凋亡无显著影响。结论 MAPK信号通路与蟾蜍灵抑制急性淋巴白血病Jurkat细胞增殖及诱导凋亡有相关性,表现为ERK和JNK促进增殖、抑制细胞凋亡;p38MAPK抑制增殖,但对凋亡无明显影响。     

MAPK通路在瑞芬太尼预处理减轻心衰大鼠离体心脏缺血/再灌注损伤中的作用

目的探讨MAPK信号通路在瑞芬太尼预处理减轻心力衰竭大鼠离体心脏缺血/再灌注损伤中的作用。方法成年♂SD大鼠,尾静脉注射阿霉素,制备慢性心力衰竭模型,通过随机数字表将54只模型大鼠分为9组(n=6):假手术组(sham)、缺血/再灌注组(IR)、瑞芬太尼预处理组(RPC)、ERK抑制剂PD98059+RPC组(RPD)、p38抑制剂SB203580+RPC组(RSB)、JNK抑制剂SP600125+RPC组(RSP)以及抑制剂对照组(PD、SB和SP)。化学比色法检测再灌注5min和10 min时冠脉流出液中乳酸脱氢酶(LDH)的活性,再灌注末行TTC染色并计算心肌梗死面积,通过Power Lab系统记录血流动力学。结果与IR组相比,RPC可以明显降低梗死面积与缺血危险区的比值(IS/AAR),同时,也可以降低再灌注5 min及10 min LDH活性;而JNK抑制剂SP600125几乎完全取消RPC的保护作用,明显增加IS/AAR,并升高再灌注5 min LDH活性;ERK抑制剂PD98059也可部分阻断RPC的保护作用;而p38抑制剂SB203580对RPC的保护作用则无明显影响。血流动力学结果显示,与IR相比,RPC及加入MAPK抑制剂后对离体心脏缺血/再灌注损伤后心功能影响差异无统计学意义。结论 JNK和ERK信号通路可能在瑞芬太尼预处理减轻心力衰竭大鼠离体心脏缺血/再灌注损伤中发挥重要作用。     

铜绿假单胞菌通过MAPK信号传导通路诱导U937细胞表达IL-8

目的探讨铜绿假单胞菌(PA)活菌对不同分化状态的U937细胞表达IL-8的诱导作用及通过MAPK信号传导通路的调控机制。方法应用人单核白血病细胞系-U937细胞,采用ELISA和RT-PCR法对PA诱导不同分化状态的U937细胞IL-8蛋白分泌和其mRNA表达进行研究,并观察MAPKs抑制剂PD98059和SB203580对IL-8表达的影响。结果PA可促进U937细胞及PMA分化的U937细胞IL-8的mRNA及蛋白分泌,而且具有明显的量效和时效关系。分别用SB203580抑制p38MAPK通路、用PD98059抑制ERK通路,均能引起抑制剂浓度依赖的IL-8的表达(P<0.01)。结论PA以浓度和时间依赖的方式感染U937细胞,促进IL-8的分泌和mRNA表达,PA可能通过MAPK信号通路启动IL-8的高效表达和分泌。     

MAPK信号转导通路在糖皮质激素耐药白血病中的研究进展

丝裂原活化蛋白激酶(MAPK)信号通路作为信号传递网络中的重要途径之一,在细胞凋亡及生存中发挥重要作用,其中最主要的是ERK、JNK及p38 MAPK途径。近来研究发现,MAPK信号转导通路与白血病的发生发展及耐药的产生有密切关系,将有可能成为白血病治疗的新靶点。本文主要综述了MAPK信号转导通路与白血病发病、治疗作用机制及与糖皮质激素耐药的关系。     

纤维连接蛋白诱导人胚肺成纤维细胞增殖的信号转导通路研究

目的探讨纤维连接蛋白(FN)诱导人胚肺成纤维细胞(HFL-1)增殖的信号转导通路。方法采用不同浓度FN刺激HFL-1并观察磷酸酰基醇-3-激酶(PI3K)信号转导通路抑制剂wortmannin(WMN)、细胞外信号调节蛋白激酶(ERK)信号转导通路抑制剂PD98059和P38蛋白激酶信号转导通路抑制剂SB203580对FN诱导HFL-1增殖作用的影响。用四甲基偶氮唑蓝(MTT)法检测各组细胞增殖情况。结果FN对HFL-1诱导增殖作用呈剂量依赖性升高趋势,在50ng/mL时作用显著;WMN,PD98059和SB203580均可抑制FN诱导的HFL-1细胞增殖。结论FN诱导HFL-1的细胞增殖可以通过PI3K和丝裂原活化蛋白激酶(MAPK)信号转导途径实现。     

MEK抑制剂联合三氧化二砷对髓系白血病细胞凋亡的研究

目的:研究MEK抑制剂PD98059联合三氧化二砷(As2O3)对髓系白血病细胞凋亡的影响及其作用机制。方法:将PD98059、As2O3单独或联合作用于髓系白血病细胞系HL-60、K562细胞,用AnnexinV-FITC法检测细胞凋亡,用流式细胞术检测Bcl-2、Caspapse-3表达。结果:联合组与单用组相比,细胞凋亡率明显增高。Bcl-2在HL-60、K562细胞均高水平表达。As2O3明显抑制HL-60细胞Bcl-2表达,对K562细胞Bcl-2无明显抑制作用。单用PD98059、As2O3及两药合用在诱导HL-60、K562细胞凋亡过程中,活化caspapse-3均明显上升,两药合用较单用PD98059或As2O3活化caspapse-3明显升高。结论:PD98059联合As2O3同时抑制ERK/MAPK和Bcl-2,激活Caspase酶,对HL-60细胞有协同促凋亡效应。两药联合同时靶向作用ERK/MAPK和BCR/ABL,活化Caspase酶,协同诱导K562细胞凋亡。PD98059可增强As2O3对髓系白血病细胞的凋亡诱导作用。     

细胞色素P450w-羟化酶抑制剂HET0016通过ERK1／2途径减轻大鼠心肌缺血再灌注损伤

目的：细胞色素P450w-羟化酶在心肌缺血再灌注（MI／R）损伤中的作用尚不十分清楚。本课题研究HET0016[N-hydroxy-N＇-（4-butyl-2 methylphenyl）formamidine]，一种新的特异性细胞色素P450w-羟化酶抑制剂对MI／R损伤的保护作用，并探讨与丝裂原活化蛋白激酶（MAPK）信号通路的关系。方法：采用大鼠MI／R模型，缺血30min，再灌注2h。将大鼠随机分为以下各组，每组6-8只：①假手术组；②模型对照组；③HET0016高低剂量给药组：在缺血前15min分别给0．1和1mg·kg-I HET0016静脉注射；⑤MAPK抑制剂组：在缺血前10min分别给予ERKl／2抑制剂PD98059（1 mg·kg-l，iv）、p38MAPK抑制剂SB203580（1mg·kg-1，iv）或JNK抑制剂SP600125（6mg·kg-1，ip）；⑥lmg·kg-1 HET0016＋MAPK抑制剂（PD98059，SB203580或SP600125）组。再灌结束后计算心肌梗死面积，测定LDH、CK和TnT水平。Westernblot检测心肌组织磷酸化ERKl／2、p38 MAPK及JNK蛋白表达水平。结果：①模型组较正常组大鼠血清LDH、CK和TnT分别升高6．43、4．13和9．7倍。HET0016剂量依赖性降低以上血清心肌酶谱水平；②HET0016高、低剂量组心肌梗死面积分别为（6．3±0．16）％和（10．3±0．2）％，与模型对照组（19.8±0．15）％比均有显著性差别；③PD98059可完全阻断HET00l6的作用，但SB20358和SP600125对其没有明显影响。④HET0016增加心肌组织磷酸化ERKl／2蛋白表达，但不影响磷酸化p38 MAPK及JNK蛋白表达。结论：HET0016通过抑制细胞色素P450w-羟化酶对大鼠MI／R损伤有保护作用，其机制与ERK1／2途径有关。     

苯甲酸钠对PC12细胞的增殖抑制及MAPKs活化表达的影响

目的观察苯甲酸钠(sodium benzoate,SB)对PC12肾上腺嗜铬细胞瘤细胞增殖的抑制作用及在此条件下细胞MAPKs信号通路活化表达的特点,为进一步了解SB的神经毒性及相关的分子机制提供实验依据。方法大鼠PC12细胞在含0~50 mmol/L浓度SB的培养基中培养24 h后,噻唑蓝(MTT)比色法检测细胞活性;Western blot检测JNK和ERK磷酸化水平的改变。结果 SB可呈一定的时间和浓度依赖性抑制PC12细胞增殖,其中40 mmol/L SB作用24 h对PC12细胞的抑制率为47.81%±5.23%;Western blot结果显示,SB处理可增加JNK的磷酸化水平并降低基础的ERK磷酸化水平;预孵SP600125 30 min后再加入SB,则能短暂降低JNK的磷酸化水平。结论 SB能够明显抑制PC12细胞的增殖,JNK和ERK信号转导通路可能参与了SB对PC12细胞的毒性作用机制。     

MAPK/ERK通过诱导纤维蛋白A磷酸化抑制垂体瘤细胞增殖、凋亡、迁移及相关信号转导

目的 探讨MAPK/ERK对垂体瘤细胞增殖、凋亡、迁移及相关信号转导的影响.方法 通过CCK-8法确定SB203580(MAPK/ERK抑制剂)的最佳安全浓度,然后将体外培养的垂体瘤细胞分为SB203580组和对照组,通过CCK-8法检测垂体瘤细胞的增殖情况,流式细胞术检测垂体瘤细胞的细胞凋亡百分数,RT-PCR和We...     

阿霉素诱导胰腺癌BxPC-3细胞凋亡过程中p38MAPK的表达

目的研究阿霉素诱导胰腺癌细胞凋亡过程中p38MAPK表达的变化,探讨p38MAPK在其中的作用。方法用膜联蛋白V-PI(annexinV-PI)染色及流式细胞技术分析阿霉素及应用p38MAPK抑制剂SB203580对胰腺癌细胞凋亡的影响,同时利用免疫细胞化学法观察经阿霉素及SB203580处理人胰腺癌BxPC-3细胞后,p38MAPK的表达水平。结果SB203580(20μmol/L)干预组胰腺癌BxPC-3细胞凋亡率为(20.1±1.4)%,阿霉素作用24 h后诱导胰腺癌BxPC-3细胞凋亡,凋亡率为(31.1±2.7)%,加用SB203580抑制p38MAPK通路后可增强阿霉素诱导的凋亡作用,凋亡率达(40.4±2.6)%。采用单因素方差分析F=136.79,组间比较组与组之间差异有统计学意义。以20μmol/L阿霉素作用BxPC-3胰腺癌细胞24 h后可见p38MAPK在细胞染色后呈现深褐色颗粒散在分布于部分或整个细胞核及细胞质内,联合应用SB203580后可见p38MAPK表达颗粒密度减低,数量减少。结论阿霉素可以活化p38MAPK通路,p38MAPK可能起到保护胰腺癌BxPC-3细胞逃避阿霉素诱导的凋亡,阻断该通路可增强阿霉素诱导胰腺癌细胞凋亡的作用。     

Affective and Anxiety Disorders and Alcohol and Drug Dependence:

Depression and anxiety frequently coexist in patients with substance use disorders. This clinically-oriented article examiens the relationship between these conditions and emphasizes data showing that substances of abuse can cause signs and symptoms of both depression and anxiety. These substance-related syndromes appear to have a different course and prognosis than uncomplicated, independent anxiety and major depressive disorders, and clinicians should consider the role of alcohol and other drugs in all patients presenting with these complaints. The authors will also outline an approach for diagnosing and managing patients with the combination of a substance use and depressive or anxiety disorder.     

Synthesis and anti-nociceptive and anti-inflammatory effects of gaultherin and its analogs

The synthesis of gaultherin (1) and its analogs was carried out to provide 11 glycosides under phase-transfer catalytic conditions. The activities of all synthesized compounds were evaluated by nitric oxide production inhibitory assay in vitro. Methyl 2-O-(4-O-β-d-galactopyranosyl)-β-d-glucopyranosylbenzoate (5f) showed significantly anti-nociceptive and anti-inflammatory effects by the evaluation in vivo. Structure–activity relationships within these compounds were discussed.     

Modelling and simulation of variability and uncertainty in toxicokinetics and pharmacokinetics

Two important methodological issues within the framework of the variability and uncertainty analysis of toxicokinetic and pharmacokinetic systems are discussed: (i) modelling and simulation of the existing physiologic variability in a population; and (ii) modelling and simulation of variability and uncertainty when there is insufficient or not well defined (e.g. small sample, semiquantitative, qualitative and vague) information available. Physiologically based pharmacokinetic models are especially suited for separating and characterising the physiologic variability from the overall variability and uncertainty in the system. Monte Carlo sampling should draw from multivariate distributions, which reflect all levels of existing dependencies in the intact organism. The population characteristics should be taken into account. A fuzzy simulation approach is proposed to model variability and uncertainty when there is semiquantitative, qualitative and vague information about the model parameters and their statistical distributions cannot be defined reliably.     

成骨细胞的功能与损伤和骨质疏松的防治

骨质疏松是一种全身性骨骼疾病,导致骨折风险增加。成人的骨量通过破骨细胞的骨吸收和成骨细胞的骨形成作用来维持动态平衡,治疗骨质疏松症的理想策略是抑制破骨细胞的骨吸收和/或增强成骨细胞的骨形成功能。目前针对保护成骨细胞及增强其功能的骨质疏松疗法相对较少。因此,本文针对成骨细胞相关功能蛋白、各种细胞损伤机制（内质网应激、氧化应激、机械过载、微小RNA和长链非编码RNA的影响等）及骨质疏松的治疗与预防作一综述,以期为针对增强成骨细胞功能的骨质疏松治疗策略提供新思路。     

Self-stimulation and amphetamine: Tolerance to d and l isomers and cross tolerance to cocaine and methylphenidate

The effects of the d and l isomers of amphetamine on self-stimulation responding were tested following acute and chronic administration. Tolerance and post-drug depression of responding occurred in tests with both isomers, indicating no role for p-hydroxynorephedrine (PHN) which is one of the metabolites of d-amphetamine. In the second experiment, d-amphetamine, methylphenidate and cocaine all produced quantitatively and qualitatively similar effects on self-stimulation responding following acute administration. Following chronic administration of d-amphetamine, animals showed tolerance to all three drugs, indicating cross-tolerance among them. These data are consistent with an hypothesis that tolerance and post-drug depression following chronic amphetamine treatment are the result of decreases in postsynaptic receptor sensitivity, which would lead to a decreased effectiveness of all three drugs, regardless of their pre-synaptic mechanisms.     

益生菌与肿瘤防治

益生菌广泛存在于自然界中,通过维持宿主体内菌群平衡、影响肠屏障功能和调节免疫应答等作用,提高宿主健康水平,被公认为"肠道健康卫士".一些益生菌可以增强机体的免疫功能,抑制致癌物质,影响肿瘤细胞的基因表达,对肿瘤具有拮抗作用.大量研究表明,益生菌在未来的肿瘤防治中有很好的应用和发展前景.     

Acamprosate and naltrexone treatment effects on ethanol and sucrose seeking and intake in ethanol-dependent and nondependent rats

Rationale  Two pharmacotherapies are approved for treating alcohol craving (acamprosate and naltrexone), but both have shown mixed findings in animals and humans. Objectives  The present experiments utilized a “reinforcer blocking” approach (i.e., rats were able to consume ethanol during treatment) to better understand the efficacy of these treatments for ethanol seeking and drinking using ethanol-dependent and nondependent rats. Materials and methods  In “nondependent” experiments, drugs (acamprosate 50, 100, and 200 mg/kg; naltrexone 0.1, 0.3, and 1.0 mg/kg) were administered over 3-week periods prior to operant sessions with a low response requirement to gain access to reinforcers for 20 min. For “dependent” experiments, rats were made dependent in vapor/inhalation chambers. Results  Acamprosate and naltrexone had similar effects on intake in nondependent and dependent rats; neither drug was selective for ethanol over sucrose drinking. In nondependent animals, naltrexone was more efficacious at more doses than acamprosate, and acamprosate’s effects were limited to a dose that also had adverse effects on body weight. Both pharmacotherapies showed more selectivity when examining reinforcer seeking. In nondependent rats, acamprosate and naltrexone had response-attenuating effects in ethanol, but not sucrose, groups. In dependent animals, acamprosate had selective effects limited to a decrease in sucrose seeking. Naltrexone, however, selectively decreased ethanol-seeking in nondependent rats. Conclusions  The naltrexone-induced decreases in seeking suggested a change in incentive motivation which was selective for ethanol in nondependent rats. The “nondependent” paradigm may model early stages of “problem drinking” in humans, and the findings suggest that naltrexone could be a good intervention for this level of alcohol abuse and relapse prevention.     

Antiinfective and encrustation-inhibiting materials--myth and facts

Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings. Physico-chemical explanation to elucidate the mechanism of such encrustation or infection inhibiting materials is still not available. Our series of experiments showed a marked decrease of silver-activity in biological fluids which corresponds with the controversial clinical results obtained with silver coated urinary catheters. Rifampicin/minocycline coated catheters had very low activity against Gram-negative rods, enterococci and Candida spp., the main causing organisms of urinary catheter infection. Surface engineered materials and antimicrobial drug delivery systems will be the next generation of sophisticated urinary catheters and stents, if both efficacy as well as efficiency has been proved clinically.     

Alprazolam and lorazepam single and multiple-dose effects on psychomotor skills and sleep

Summary The effects of alprazolam 0.5 mg and lorazepam 2 mg on cognitive and psychomotor skills were assessed in twelve normal volunteer subjects in a randomised, double-blind, crossover design. Single and multiple dose effects were monitored using a battery of tests comprising critical flicker fusion threshold (CFFT), choice reaction time (CRT), simulated car tracking, and subjective ratings of perceived sedation (LARS) and of sleep behaviour (LSEQ). Compared with placebo baseline scores, treatment with lorazepam 2 mg (both single and multiple doses) resulted in a widespread impairment of CRT, tracking accuracy, and CFFT. Single doses of alprazolam 0.5 mg reduced CFFT with respect to the placebo baseline. Single and multiple dose treatment with both drugs resulted in subjective reports of sedation, a reduction of sleep onset latency, and improved sleep quality. Only lorazepam 2 mg significantly disrupted the integrity of behaviour on waking from sleep. These results suggest important pharmacodynamic differences between the two drugs in the doses used.