SOCS1在糖尿病小鼠肾小管间质病变中的作用

该文探讨了细胞因子信号传导抑制蛋白1(suppressors of cytokine sigmaling 1,SOCS1)在糖尿病小鼠肾小管间质病变中的作用。通过腹腔注射链脲佐菌素(streptozotocin,STZ)诱发糖尿病小鼠模型,于成模后8周给予尾静脉快速注射p EF-FLAG-I/m SOCS1质粒(1 mg/kg),每隔7 d注射一次。于成模后12周收集标本,检测各组动物的血糖、24 h尿蛋白;应用RT-PCR检测肾组织中SOCS1、角蛋白18(cytokeratin,CK18)和α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)m RNA的表达;应用免疫组化或Western blot检测SOCS1、CK18、α-SMA和纤维黏连蛋白(fibronectin,FN)的表达;酶联免疫吸附实验检测肾组织中白细胞介素-1β(interleutin-1β,IL-1β)和转化生长因子-β1(transforming growth factor-β1,TGF-β1)的表达;流式细胞术检测肾皮质中巨噬细胞标志蛋白CD68的表达。结果发现,与对照组相比,糖尿病小鼠肾组织中IL-1β、TGF-β1及FN的表达增强,巨噬细胞的数量增多;此外,肾小管上皮细胞自身标志蛋白CK18的表达减少而肌成纤维细胞标志蛋白α-SMA的表达增强。SOCS1质粒转染能降低24 h尿蛋白、抑制肾组织中CD68、IL-1β、TGF-β1和α-SMA的表达,同时部分恢复CK18的表达。结果表明,SOCS1可能通过抑制肾组织炎症反应和肾小管上皮细胞转分化从而缓解糖尿病小鼠肾小管间质病变。     

抑瘤素M在狼疮鼠肾组织中的表达及意义

该文探讨了抑瘤素M(oncostatin M,OSM)在狼疮鼠肾组织中的表达及意义。以MRL/Mp J鼠作为正常对照鼠,MRL/lpr鼠随作为狼疮鼠。收集动物血、尿进行生化指标检测;收集肾组织后免疫组织化学和酶联免疫吸附实验检测OSM的表达情况;qRT-PCR和Western blot分别检测E-钙黏蛋白(E-cadherin)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)及I型胶原(collagen I,Col I)mRNA和蛋白的表达;实时荧光定量PCR(quantitative Real-time PCR,qRT-PCR)检测纤维黏连蛋白(fibronectin,FN)mRNA的表达。结果发现,与对照鼠相比,狼疮鼠肾组织中OSM的表达明显增多,且其表达与血尿素氮、24 h尿蛋白及α-SMA、Col I和FN的表达呈正相关,而与E-cadherin的表达呈负相关。结果表明,OSM在狼疮鼠肾组织中的表达升高,且其高表达可能与狼疮鼠肾功能减退及肾小管上皮细胞转分化有一定的关系。     

白介素-1β对高糖刺激的人肾小管上皮细胞转分化的影响

目的探讨炎症细胞因子白介素-1β（interleukin-1βIL-1β）对高糖刺激的人肾小管上皮细胞转分化的影响。-方法体外培养人肾近曲小管上皮细胞株（HKCs）,随机分为正常对照组（5.5 mmol/L normal glucose）;高糖组（30 mmol/L high glucose）;高糖＋IL-1β（5ng/ml）组。分别于处理后24h、48h、72h收集细胞,采用免疫细胞化学染色和Western蛋白印迹法检测细胞角蛋白-18（cytokeratin-18 CK-18）、α-平滑肌肌动蛋白（α-smooth muscle actinα-SMA）水平。结果高糖能够诱导肾小管上皮细胞α-SMA蛋白的合成增加,而肾小管上皮细胞的标志物CK-18的表达逐渐减少;IL-1β与高糖同时刺激可使肾小管上皮细胞α-SMA蛋白表达进一步增多,而其自身标志物CK-18的表达则明显下降。结论炎症因子IL-1β能增强高糖对肾小管上皮细胞转分化的作用。     

大黄素对TGF-β1诱导的肾小管上皮细胞间质转分化的影响

目的:探讨大黄素对TGF-β1诱导的人肾小管上皮细胞(HK-2)间质转分化的影响。方法:不同浓度大黄素分别作用于TGF-β1诱导HK-2细胞24 h和48 h,通过细胞增殖实验确定最佳大黄素最佳给药浓度。TGF-β1诱导HK-2细胞24 h后收集细胞用于免疫印迹Western blot和实时荧光定量PCR(RT-PCR)分析。Western印迹法分别检测纤维化相关蛋白Collagen IV的表达,和肾小管上皮细胞向间充质细胞转分化关键蛋白α-SMA和E-Cadherin的表达;RT-PCR法检测肾小管上皮细胞向间充质细胞转分化关键蛋白α-SMA的表达。结果:由细胞增殖实验结果表明40μM大黄素是最佳给药浓度。Western结果表明,与模型组相比,大黄素组下调纤维化相关蛋白Collagen IV的表达,大黄素组与模型组蛋白差异有统计学意义(P0.05)。与模型组相比,大黄素组下调α-SMA蛋白表达水平,而上调E-Cadherin蛋白表达,差异有统计学意义(P0.05)。RT-PCR结果表明,与模型组相比,大黄素组降低α-SMA mRNA的含量,大黄素组与模型组α-SMA mRNA含量差异有统计学意义(P0.05)。结论:大黄素可通过抑制TGF-β1诱导的HK-2细胞间质转分化,从而发挥延缓肾间质纤维化的过程。     

糖基化终末产物（AGEs）诱导下SOCS基因在肾小管上皮细胞中的表达及意义

目的观察SOCS-1、SOCS-3在肾小管上皮细胞（HKC）中的基础表达及在糖基化终末产物（AGEs）诱导下的表达及意义。方法体外培养HKC细胞,随机分为正常对照组、AGEs组,倒置显微镜观察细胞形态学改变,采用流式细胞术,免疫细胞化学和检测SOCS-1、SOCS-3蛋白表达,RT-PCR法检测HKCSOCS-1、SOCS-3 mRNA表达。结果与正常组比较,AGES诱导的肾小管上皮细胞发生形态学改变;免疫细胞化学、流式细胞学发现SOCS-1、SOCS-3表达以胞浆为主,散在胞核表达;12、24、48hSOCS-1、SOCS-3蛋白表达AGEs组均高于正常对照组,差异有统计学意义,其中SOCS-1以12h表达量最大,SOCS-3以24h表达最高,RT-PCR检测SOCS-3 mRNA表达量,AGEs组高于正常组,差异有统计学意义。结论SOCS-1、SOCS-3在正常肾小管上皮细胞中有基础表达,AGEs可诱导肾小管上皮细胞SOCS-1、SOCS-3表达上调,为我们进一步研究SOCS基因与糖尿病肾病的关系提供了理论依据。     

SREBP-1基因过表达促进人肾小管上皮细胞甘油三酯形成

目的 SREBP-1重组质粒转染人肾小管上皮细胞(HKC)检测SREBP-1基因表达和细胞内脂滴的关系。方法体外培养人肾小管上皮细胞并随机分为空白对照组、pcDNA3.1空质粒对照组和pcDNA3.1-SC1重组质粒转染组,采用阳离子脂质体法将SREBP-1特异性质粒pcDNA3.1-SC1及pcDNA3.1空质粒转染到细胞内并培养48小时,半定量RT-PCR和Westernblot分析目标基因表达丰度的变化,并采用油红O染色检测细胞内脂滴。结果 pcDNA3.1-SC1重组质粒转染的细胞内SREBP-1mRNA表达呈现明显升高,扩增条带积分光密度值分别是空白对照组和阴性对照组的6.158倍和4.194倍,SREBP-1蛋白也出现明显上调,条带积分光密度值为3.092±0.254。空白对照组和pcDNA3.1阴性对照组细胞内均未见有红染脂滴颗粒,而pcDNA3.1-SC1重组质粒转染组中出现了清晰的红染颗粒。结论 SREBP-1表达可增加人肾小管上皮细胞脂肪合成证实HKC细胞中SREBP-1表达和脂滴形成之间存在有直接关系。     

高脂喂养大鼠肾小管上皮细胞SREBP-1、TGF-β1、α-SMA的表达和细胞外基质沉积

目的:探讨高脂喂养对大鼠肾脏小管上皮细胞SREBP-1、TGF-β1、α-SMA表达和细胞外基质(ECM)的影响。方法:高脂饲料喂养大鼠12周后,油红O检测肾脏脂质沉积,Masson染色检测肾小管间质细胞外基质沉积,免疫组化、Western blot和原位杂交检测SREBP-1、TGF-β1、α-SMA和FN的表达。结果:高脂喂养后大鼠体重明显增加,血糖、甘油三酯和胰岛素均升高,油红O检测显示大鼠肾小管上皮细胞内出现明显脂滴。SREBP-1蛋白和mRNA在肾小管上皮细胞内表达,高脂组高于正常对照组,分别是正常组的1.88倍和1.85倍;TGF-β1和α-SMA也定位于肾小管上皮细胞胞浆并出现上调。Masson染色显示高脂喂养大鼠肾间质ECM沉积增多,纤维粘连蛋白FN检测也显示模型组表达强于对照组。结论:高脂饮食喂养可能通过上调肾脏小管上皮细胞SREBP-1表达使细胞内脂滴沉积,并进一步诱导TGF-β1、α-SMA合成而导致细胞外基质堆积。     

p38 MAPK介导高糖诱导的肾小管上皮细胞向间充质细胞转变

本文旨在观察p38MAPK与高糖诱导的肾小管上皮细胞向间充质细胞转变之间的关系。将雄性Sprague—Dawley（SD）大鼠随机分为对照组、糖尿病组、胰岛素治疗组,用免疫组织化学、Western blot检测p38MAPK和磷酸化p38MAPK（P—p38MAPK）蛋白表达。采用机械分离和酶消化获取SD大鼠肾小管节段,进行肾小管上皮细胞培养,将肾小管上皮细胞分为对照组、高渗组（20mmol／L D—mannitol）、高糖组（20mmol／L D—glucose）和SB202190（p38MAPK特异性抑制剂）＋高糖组,处理72h后收集细胞,用免疫细胞化学检测α-平滑肌肌动蛋白（α—smooth muscleactin,α-SMA）、p-p38MAPK和Snaill蛋白表达,Western blot检测p38MAPK、p-p38MAPK、Snaill、转化生长因子β1（transforming growth factor—β1,TGF-β1）、α-SMA和E-cadherin的表达,RT-PCR检测α-SMA和E-cadherin mRNA的表达。体内和体外结果均显示,高糖状态激活了p38MAPK,这种活化作用在体内可因胰岛素控制血糖而被消除,在体外可被p38MAPK特异性抑制剂SB202190显著抑制;高糖组α-SMA蛋白和mRNA在原代培养肾小管上皮细胞的表达较对照组分别增加12倍和8倍（P〈0．01）,SB202190处理组其表达则较高糖组分别减少67％和50％（P〈0．01）。SB202190不影响TGF—β1蛋白表达,但下调Snaill蛋白表达,并部分恢复高糖组E—cadherin蛋白和mRNA的表达。上述结果提示,p38MAPK可能通过转录因子Snaill介导高糖诱导的肾小管上皮细胞向间充质细胞转变。     

p~(38)MAPK在IL-18诱导肾小管上皮细胞转分化中的作用

目的:白细胞介素18(IL-18)可诱导肾小管上皮细胞转分化,本研究探讨其是否是通过p38MAPK途径而起作用。方法:应用不同浓度的p38MAPK通路特异性阻断剂SB203580(0、5、10、20μmol/L)预孵育人近端肾小管上皮细胞(HK-2细胞)30min后,加入IL-18(100ng/ml)共培养24、48、72h。应用RT-PCR法检测α-平滑肌肌动蛋白(α-SMA)mRNA的表达水平;应用ELISA法测定细胞浆中α-SMA蛋白质含量。结果:SB203580呈剂量依赖性地抑制IL-18诱导的HK-2细胞α-SMA基因表达(P0.05)。结论:p38MAPK通路是调控IL-18诱导肾小管上皮细胞转分化的主要信号通路之一。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.