棉酚对仔猪睾丸支持细胞氧化应激和细胞凋亡的影响

以原代分离培养仔猪睾丸支持细胞为模型,经含不同浓度(0、2.5、5、10、20、40、80、160μmol/L)乙酸棉酚或40μmol/L乙酸棉酚加800μmol/L的乙酰半胱氨酸(NAC)的培养基培养24 h后,检测细胞增殖率、细胞内活性氧(ROS)水平和丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性、培养基中乳酸脱氢酶(LDH)活性及细胞凋亡情况,研究棉酚对仔猪睾丸支持细胞的氧化应激及细胞凋亡的影响。结果显示:棉酚呈浓度依赖性抑制仔猪睾丸支持细胞增殖率,棉酚浓度大于等于10μmol/L时,细胞增殖率极显著降低;棉酚造成细胞内ROS水平显著升高、SOD活性显著降低、MDA含量升高及培养基中LDH活性升高;NAC显著抑制棉酚诱导的细胞内ROS水平升高、细胞增殖抑制及细胞凋亡。表明棉酚能诱导仔猪睾丸支持细胞凋亡,这可能与过量ROS生成而造成细胞氧化应激有关。     

活性氧与一氧化氮在逆境胁迫下的相互关系

简要介绍了逆境胁迫下活性氧、一氧化氮与其他信号分子之间的相互关系,非生物胁迫尤其是水分胁迫下活性氧自由基对植物的伤害机理及一氧化氖与活性氧的响应,生物胁迫植物抗病虫反应中一氧化氮与活性氧的表现及相互关系。     

乙烯在Tm-2~2抗ToMV反应中激发ROS发生并导致细胞死亡(英文)

番茄的抗病基因Tm-22对Tobamoviruses属病毒有持续抗性.鉴于Tm-22基因在烟草(Nicotianatabaccum)上能够功能表达,我们可以应用这一体系来了解Tm-22抗ToMV反应中氧离子自由基(ROS)的产生机制.瞬间表达的研究结果表明,ROS能够被外源的乙烯和ACC诱导,持续的乙烯刺激和应用高浓度的ACC能够导致细胞坏死并伴随着ROS的产生.     

碳酸盐胁迫对偃伏梾木活性氧产生和抗氧化酶系统的影响

为评价偃伏梾木(Cornus stolonifera Michx.)的耐盐性,采用盆栽方法对1年生苗木在不同质量分数的NaHCO3(1.0、2.0、4.0g/kg沙土)的胁迫(7,14、21d)下叶片活性氧产生和清除系统的变化和膜质过氧化过程进行了研究.结果表明,短期胁迫时,偃伏梾木在各盐处理下叶片O-.2产生速率和H2O2的含量与对照无显著差异;CAT和APX酶活性大部分显著升高(P<0.05),分别达到对照的1.8～3.0、1.0～2.0倍;SOD活性无显著变化;丙二醛、电解质外渗率与对照无显著差异.中期胁迫叶片O-.2产生速率和H2O2的含量分别达到对照的1.9～2.9和1.2～1.5倍(P<0.05);SOD、CAT和APX酶活性均显著增加(P<0.05),SOD和CAT在中盐处理下达到最高,APX在高盐处理下达到最高;MDA含量、电解质外渗率在中低盐处理下与对照无显著差异,高盐胁迫下分别达到对照的3.0和1.4倍(P<0.05).长期胁迫叶片O-.2产生速率和H2O2的含量为对照的1.3～1.6和1.3～1.9倍(P<0.05);SOD活性在高盐处理下降低,接近对照,CAT比对照降低38%(P<0.05),APX酶仍保持较高活性(P<0.05);MDA含量、电解质外渗率分别是对照的1.3～4.7和1.8～2.8倍(P<0.05).偃伏梾木对低于2.0g/kg沙土的碳酸盐胁迫有一定的适应性.     

鳗弧菌注射对栉孔扇贝免疫活性的影响

测定了鳗弧菌(Vibrio anguillarum)注射对栉孔扇贝(Chlamys farreri)胞内活性氧(ROS)含量和过氧化氢酶(CAT)、酸性磷酸酶(ACP)和碱性磷酸酶(ALP)活性的影响。结果表明,在注射后5、24、48和72h各免疫指标都有明显变化;胞内ROS含量在24、48和72h明显升高,且均高于对照组,形成抛物线趋势,在48h达到最高;血清中CAT活性均有升高趋势;肝脏中ACP活性在24、48和72h与注射生理盐水组相比明显升高;栉孔扇贝体内ALP活性有明显升高的趋势,且在注射后24h活性达到最高,而后有所下降。结果表明,鳗弧菌对栉孔扇贝免疫系统有明显的刺激作用。     

Valorization of the whole grains of Triticum aestivum L. and Triticum vulgare L. through the investigation of their biochemical composition and in vitro antioxidant,anti-inflammatory,anticancer and anticalpain activities

Two locally grown wheat species named Triticum aestivum L. and Triticum vulgare L. were studied for their phytochemical contents and their biological activities. T. vulgare presented the highest amounts of total phenolic compounds and ascorbic acids while T. aestivum was found to be rich in flavonoids, flavonols, proanthocynidins and ortho-diphenols. Eleven carotenoids were identified in T. vulgare where the most dominant compounds belongs to α-carotene and its derivatives while T. aestivum presented seven carotenoids. This later presented the highest DPPH radical scavenging activity and exhibited a strong reducing power in FRAP, phosphomolybdenum, hydrogen peroxide and reducing power assays. T. vulgare extract was found to be effective in metal chelating power and in scavenging nitric oxide radical. No significant differences in scavenging ABTS and hydroxyl radicals were noted between the two wheat species. T. aestivum inhibited xanthine oxidase and ROS production and showed the best cytotoxic effect while T. vulgare extract exhibited anti-calpain activity.     

甜菜碱参与西瓜抗枯萎病的初步探究

为探究甜菜碱在参与西瓜抗枯萎病方面的作用,本研究以西瓜悬浮细胞为试验材料,利用镰刀菌酸诱导,测定细胞活性氧(ROS)的变化情况以及甜菜碱合成相关基因的表达变化等。结果表明:镰刀菌酸对西瓜细胞的生长有明显的抑制作用,通过外源添加甜菜碱可以缓解低浓度(≤100μmol/L)下镰刀菌酸的胁迫;通过镰刀菌酸诱导西瓜细胞,可以使细胞内ROS迅速升高,并在30 min达到最大值,而同时添加甜菜碱处理可以明显降低细胞ROS含量;此外,镰刀菌酸诱导可以使甜菜碱合成基因Cl BADH和Cl CMO基因表达量呈现先上升后缓慢下降的趋势,且0.5 h相对表达量达到最高,这证明镰刀菌酸对西瓜甜菜碱合成基因Cl BADH和Cl COM的表达有不同程度诱导作用。上述研究结果初步表明甜菜碱在参与西瓜抗枯萎病方面具有一定作用,为加强对西瓜枯萎病抗病机制的探索和发掘抗性相关基因提供了理论支持。      

Chemical profiling and biological screening of Thymus lotocephalus extracts obtained by supercritical fluid extraction and hydrodistillation

Essential oil and extracts from the aerial parts of Thymus lotocephalus were obtained by hydrodistillation (HD) and supercritical fluid extraction (SFE) in two different collectors, respectively. SFE was conducted at 40 °C and a working pressure of 12 or 18 MPa. The chemical profiles were determined using GC-FID and GC-IT-MS. Oxygen-containing monoterpenes were the primary constituents in the essential oil and SFE extracts collected in the second separator, while the extracts obtained in the first separator were predominantly oxygen-containing sesquiterpenes. A large number of compounds were identified by hydrodistillation and, in contrast, the highest extraction yields were obtained using SFE. Linalool (10.43 ± 1.63%) was the main component in essential oil, whereas camphor (7.91 ± 0.84%) and cis-linalool oxide (7.25 ± 1.45%) were the major compounds in the extracts-2nd separator obtained at pressures of 12 and 18 MPa, respectively. Caryophyllene oxide was the primary constituent identified in the extracts-1st separator (4.34 ± 0.51 and 4.41 ± 1.25% obtained at 12 and 18 MPa, respectively). The antioxidant activity was assessed by ORAC and DPPH assays, and the anti-cholinesterase activity was evaluated in vitro using Ellman's method. The essential oil and SFE extracts (first separator) of T. lotocephalus possessed antioxidant activity and strongly inhibited cholinesterases. We also demonstrated that the acetylcholinesterase and butyrylcholinesterase inhibitory activities of the essential oil could be attributed to 1,8-cineole and caryophyllene oxide, respectively.     

腐殖质促进植物根和地上部生长的信号传导和串扰机制研究进展

天然高分子异构混合物腐殖质（HS）是陆地生态系统的重要组成部分,其促生作用近年来被广泛研究,其中多条信号通路在 HS 促进植物生长发育过程中起到重要作用。该文综述了 HS 促进植物根和地上部生长发育的信号通路传导及串扰机制。HS 在促进根系生长过程中吲哚乙酸（Indole-3-acetic acid,IAA）、一氧化氮（Nitric oxide,NO）、脱落酸（Abscisic acid,ABA）、活性氧（Reactive oxygen species,ROS）和 Ca2+ 等信号通路传导及相互串扰过程参与其中;HS 在促进地上部生长过程中细胞分裂素（Cytokinin,CTK）、ABA 和硝酸盐信号通路发生复杂的传导和相互串扰过程。HS 通过复杂的代谢网络调控植物生理代谢,调节机制涉及多条复杂信号通路的传导和串扰过程,其中质膜 H+-ATPase 是 HS 促进地下和地上部生长机制研究中的关键节点,多条信号通路通过质膜 H+-ATPase 介导相互级联放大的信号传导。在 HS 调控根系和地上部生长发育过程中,信使 NO 与多条信号通路间发生复杂的串扰过程,是参与 HS 促生作用的重要串扰信号分子。HS 在触发根和地上部生长发育过程中还存在其他信号通路,其中防御信号通路水杨酸（Salicylicacid,SA）和茉莉酸（Jasmonic acid,JA）受到信号通路 IAA、NO、ABA 和 CTK 等的调节。由于 HS 具有分散性、异质性和生物化学研究复杂性的特点,至今尚未明确 HS 对植物生长短期作用机制以及在整个植物生长周期内的整体作用机制,因此需要进一步深入分析揭示促生过程中所涉及到的信号传导、交叉、串扰和整合途径,以及复杂的营养和代谢通路,为 HS 生理活性作用机制和农业生产应用的研究提供理论依据。     

伏马菌素B1诱导Marc-145细胞caspase非依赖型程序性细胞死亡

[目的]以Marc-145细胞为模型,研究了伏马菌素B1能否导致细胞产生其他类型程序性细胞死亡。[方法]利用caspase抑制剂、蛋白合成抑制剂、非凋亡程序性细胞死亡necroptosis抑制剂及ROS抑制剂,分别抑制caspase活性、蛋白质合成、necroptosis和ROS,采用结晶紫染色和AnnexinV-FITC/PI双染分析这些抑制剂对伏马菌素B1诱导Marc-145细胞死亡的影响。[结果]caspase、necroptosis抑制剂和2种自由基抑制剂不能抑制伏马菌素B1诱导的Marc-145细胞死亡,但蛋白合成抑制剂则可以显著抑制伏马菌素B1诱导的Marc-145细胞死亡。[结论]伏马菌素B1所诱导的Marc-145细胞的死亡是一种受基因表达调控的程序性细胞死亡,但与caspase、ROS和nec-roptosis无关。