右美托咪定调控Nrf2/HO-1通路对H2O2诱导心肌细胞氧化应激损伤的保护作用

摘要：目的:探讨右美托咪定通过调控核因子E2相关因子2（Nrf2）/血红素氧合酶-1（HO-1）通路对过氧化氢（H2O2）诱导的心肌细胞氧化应激损伤发挥保护作用。方法:体外培养H9c2心肌细胞,选择对数生长期细胞进行实验,分为对照组、模型组、右美托咪定低、中、高剂量组。对照组不进行处理;模型组加入终浓度为200μmol·L-1的H2O2;右美托咪定低、中、高剂量组分别加入终浓度为5,10,20μmol·L-1的右美托咪定,同时给予终浓度为200μmol·L-1的H2O2,继续培养24 h后,检测各组细胞存活率、凋亡率、细胞中抗氧化指标、一氧化氮（NO）、肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）、HO-1和Nrf2蛋白变化情况。结果:与对照组相比,模型组和右美托咪定各剂量组H9c2细胞存活率、谷胱甘肽（GSH）、NO、HO-1和Nrf2蛋白水平降低（P<0.05）,凋亡率、乳酸脱氢酶（LDH）、丙二醛（MDA）、活性氧（ROS）、TNF-α和IL-6升高（P<0.05）;与模型组相比,右美托咪定各剂量组H9c2细胞存活率、GSH、NO、HO-1和Nrf2蛋白水平升高（P<0.05）,凋亡率、LDH、MDA、ROS、TNF-α和IL-6降低（P<0.05）,且右美托咪定各剂量组之间上述指标呈剂量依赖性（P <0.05）。结论:右美托咪定可能通过激活Nrf2/HO-1通路,减轻心肌细胞的氧化损伤,促进细胞增殖和抑制细胞凋亡,从而发挥心肌保护作用。     

咪达唑仑对低氧/复氧诱导的HK-2细胞凋亡及Nrf2/HO-1通路的影响

摘要：目的:探讨咪达唑仑对低氧/复氧诱导HK-2细胞凋亡的作用,及对核因子E2相关因子2（Nrf2）/血红素加氧酶-1（HO-1）通路的影响。方法:HK-2细胞分为正常对照组、低氧/复氧组、不同浓度(2,4,8μmol·L-1)咪达唑仑组,CCK-8法检测细胞活性,流式细胞术检测细胞凋亡情况,试剂盒检测细胞活性氧簇（ROS）和丙二醛（MDA）含量以及超氧化物歧化酶（SOD）活性,蛋白质免疫印迹技术（WB）检测HK-2细胞Nrf2和HO-1表达水平。结果:相较于正常对照组,低氧/复氧组细胞活性及SOD活性明显降低（P<0.05）,细胞凋亡率、ROS和MDA含量明显升高（P<0.05）。相较于低氧/复氧组,咪达唑仑各浓度组细胞活性、SOD活性及Nrf2和HO-1表达明显升高（P<0.05）,细胞凋亡率、ROS和MDA含量明显降低（P<0.05）,且呈剂量依赖性。结论:咪达唑仑可促进Nrf2/HO-1信号通路,提高细胞抗氧化能力,抑制低氧/复氧诱导的HK-2细胞凋亡。     

纳米铜对肾细胞的氧化损伤作用

目的研究氧化应激在纳米铜引起肾细胞毒性中的作用。方法通过检测细胞内活性氧生成、金属硫蛋白表达、谷胱甘肽和丙二醛含量来了解纳米铜对肾细胞的氧化损伤作用。结果纳米铜可以剂量依赖性方式诱导细胞内ROS含量升高。20 mg.L-1纳米铜与细胞作用24 h,细胞内MT表达均明显增强。将0～40 mg.L-1纳米铜与HK-2细胞作用24 h,可引起细胞内GSH,培养上清中的MDA水平均呈剂量依赖性升高,而细胞内MDA、CuZn-SOD水平升高不明显。结论纳米铜在一定剂量和暴露时间条件下破坏了肾细胞内活性氧与抗氧化物质的动态平衡,引起氧化应激,这是纳米铜引起毒性损伤的机制之一。     

丹参素对地塞米松诱导MC3T3-E1成骨细胞损伤的保护作用

目的 探讨丹参素对地塞米松诱导MC3T3-E1成骨细胞损伤的保护作用。方法 构建地塞米松1μmol/L诱导MC3T3-E1成骨细胞损伤模型;其中,C、D、E组分别采用丹参素10、20、40μmol/L预处理。另设空白对照组(A组)和地塞米松1μmol/L模型对照组(B组)。MTT法检测细胞存活率,二硝基苯肼法和流式细胞术分别检测乳酸脱氢酶(LDH)和活性氧(ROS)水平,Western blot检测p21、核因子E2相关因子2(Nrf2)和血红素氧合酶1(HO-1)蛋白水平。检测丹参素40μmol/L预处理小干扰RNA沉默p21表达(F组)后地塞米松1μmol/L诱导MC3T3-E1成骨细胞(G组)的细胞存活率以及Nrf2和HO-1蛋白水平。结果 与A组比较,B、C、D、E组细胞存活率降低,LDH和ROS水平升高,且p21、Nrf2和HO-1蛋白表达水平升高(P<0.05)。与B组比较,C、D、E组细胞存活率和p21、Nrf2和HO-1蛋白表达水平呈丹参素浓度依赖性升高,而LDH和ROS水平降低(P<0.05)。G组细胞存活率高于B组,但低于E组(P<0.05)。G组...     

黄腐醇对SH-SY5Y细胞氧化应激损伤的保护机制研究

摘要：目的:研究黄腐醇体外缓解过氧化氢（H2O2）诱导SH-SY5Y细胞死亡的抗氧化损伤机制。方法:体外培养SH-SY5Y细胞,采用MTT法分别研究不同浓度的黄腐醇对SH-SY5Y细胞的毒性作用和对H2O2诱导细胞损伤的保护作用;采用流式细胞仪和显微成像实验检测黄腐醇对细胞内活性氧（ROS）水平的影响;采用免疫荧光实验检测黄腐醇对核因子E2相关因子2（Nrf2）核转位的影响及用Western Blot分析黄腐醇对抗氧化蛋白血红素加氧酶-1（HO-1）和谷氨酸半胱氨酸连接酶催化亚基（GCLC）的影响。结果:黄腐醇浓度≤0.5μmol·L-1时对SH-SY5Y细胞无毒性作用,黄腐醇对H2O2诱导的细胞损伤具有浓度依赖性保护作用（P<0.05或P<0.01）;同时黄腐醇能降低H2O2诱导的细胞内ROS水平和促进Nrf2核转位（P<0.05）及浓度依赖性地提高HO-1和GCLC蛋白的表达（P<0.05或P<0.01）。结论:黄腐醇具有一定的细胞保护作用,其通过激活Nrf2通路缓解H2O2诱导SH-SY5Y细胞的氧化损伤。     

茯苓酸调节Nrf2/Keap1/ARE信号通路改善脂多糖诱导肺泡上皮细胞氧化应激损伤研究

摘要：目的:研究茯苓酸（PA）对脂多糖（LPS）诱导的人肺泡上皮细胞氧化应激损伤的影响,以及核因子红细胞2相关因子2/Kelch样ECH关联蛋白1/抗氧化反应元件（Nrf2/Keap1/ARE）信号通路在此过程中的作用。方法:培养人肺泡上皮细胞HPAEpiC,使用CCK-8法筛选适合的PA处理浓度。将HPAEpiC细胞分为Control组、LPS组、LPS+PA组、LPS+PA+sh-NC组和LPS+PA+sh-Nrf2组。TUNEL染色法检测各组HPAEpiC细胞凋亡情况;检测各组HPAEpiC细胞中活性氧（ROS）的产生、丙二醛（MDA）水平以及总超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-Px）活性;Western blot检测各组HPAEpiC细胞中p53、B淋巴细胞瘤-2基因相关X蛋白（Bax）、Nrf2、Keap1和血红素氧化酶1（HO-1）蛋白表达情况。结果:根据CCK-8结果选用4μmol·L-1的PA用于后续研究。LPS诱导后HPAEpiC细胞中TUNEL阳性细胞率与p53和Bax蛋白水平均升高;ROS的产生、MDA水平均增高,SOD和GSH-Px活性降低;Nrf2、HO-1蛋白质水平减少,Keap1蛋白质水平增加（P＜0.05）。使用PA处理可以减轻LPS诱导对以上指标的影响（P＜0.05）。敲低Nrf2可部分逆转PA处理对LPS诱导的HPAEpiC细胞的影响（P＜0.05）。结论:PA可抑制LPS诱导的肺泡上皮细胞氧化应激损伤和凋亡反应,其机制可能与激活Nrf2/Keap1/ARE信号通路有关。     

太白楤木活性成分竹节参皂苷Ⅳa抗氧化及抗衰老作用研究

目的探讨太白楤木皂苷中的重要成分竹节参皂苷Ⅳa(CHS)抗氧化及抗衰老作用。方法取5~8代的小鼠胚胎成纤维细胞(MEFs),使用过氧化氢(H2O2)诱导细胞氧化应激以及细胞衰老模型。MTT法分别检测不同浓度CHS及H2O2对细胞活力的影响;DCFH-DA染色流式细胞仪检测细胞总活性氧(ROS)水平;Mito SOX染色流式细胞仪检测细胞线粒体ROS水平;衰老相关β-半乳糖苷酶(SA-β-gal)染色检测细胞衰老状态;Western blot法检测衰老标志蛋白p53、p21蛋白表达水平以及关键抗氧化应激Nrf2通路(Nrf2、HO-1、GCLC、GCLM)蛋白表达。结果浓度≤160μg·m L-1的CHS对MEFs细胞无明显毒性作用;H2O2能够显著提高细胞总ROS和线粒体ROS水平,诱导细胞衰老指标SA-β-gal活性增加,提高p53、p21表达水平,提高抗氧化信号通路Nrf2通路表达水平。CHS能够剂量依赖地降低H2O2诱导的细胞总ROS和线粒体ROS水平,减轻H2O2诱导的SA-β-gal活性升高,抑制p53、p21以及Nrf2、HO-1、GCLC、GCLM蛋白表达水平的升高。结论 CHS具有显著的抗氧化应激和抗衰老作用。     

BMAL1对H2O2诱导的H9C2心肌细胞损伤的影响及机制探讨

目的 探讨节律基因BMAL1对过氧化氢（H2O2）诱导的H9C2心肌细胞损伤的影响及机制。方法 构建 BMAL1稳定过表达的H9C2细胞系后,实验分为2个部分。（1）实验1。对照组、H2O2组（0.2 mmol/L的H2O2处理24 h）、 BMAL1 过表达（BMAL1-OE）组（BMAL1 稳定过表达 H9C2 细胞）、BMAL1 过表达+H2O2（BMAL1-OE+H2O2）组 （0.2 mmol/L的H2O2处理BMAL1稳定过表达H9C2细胞24 h）。（2）实验2。H2O2组、BMAL1-OE+H2O2组、BMAL1过表 达+抑制 NRF2+H2O2（BMAL1-OE+ML385+H2O2）组（NRF2 抑制剂 2 μmol/L 的 ML385 预处理 BMAL1 稳定过表达 H9C2 细胞 24 h,再用 0.2 mmol/L 的 H2O2处理 24 h）、BMAL1 过表达+抑制 HO-1+H2O2（BMAL1-OE+Znpp+H2O2）组 （HO-1抑制剂5 μmol/L的Znpp预处理BMAL1稳定过表达H9C2细胞24 h,再用0.2 mmol/L的H2O2处理24 h）。CCK-8 法检测细胞活力,羟胺法检测超氧化物歧化酶（SOD）活性、TBA 法检测丙二醛（MDA）含量,Western blot 法检测 BMAL1、核因子 E2 相关因子 2（NRF2）和血红素加氧酶-1（HO-1）蛋白表达水平。结果 （1）与 Control 组相比, BMAL1-OE组BMAL1 mRNA表达水平升高,H2O2组细胞活力和细胞上清液SOD活性下降、MDA含量增加,BMAL1、 NRF2和HO-1蛋白相对表达水平降低（P＜0.05）;与H2O2组相比,BMAL1-OE+H2O2组细胞活力和细胞上清液SOD活 性增加,MDA 含量减少,而 BMAL1、NRF2 和 HO-1 蛋白相对表达水平升高（P＜0.05）;（2）与 BMAL1-OE+H2O2组相 比,BMAL1-OE+ML385+H2O2组和BMAL1-OE+Znpp+H2O2组细胞活力和细胞上清液SOD活性降低,MDA含量增加 （P＜0.05）。结论 BMAL1可能通过上调NRF2/HO-1信号轴,减轻H2O2诱导的大鼠心肌细胞氧化应激损伤。     

丹皮酚对过氧化氢诱导的PC12细胞凋亡的抑制作用(英文)

目的探讨丹皮酚对过氧化氢(H2O2)诱导的PC12细胞凋亡的抑制作用及其机制。方法建立H2O2致PC12细胞损伤模型,采用MTT法测定细胞存活率,流式细胞术测定细胞凋亡率及细胞内活性氧含量,化学比色法测定乳酸脱氢酶(LDH)释放量及细胞内丙二醛(MDA)含量。结果PC12细胞经H2O2100μmol.L-1处理10 h可致细胞存活率下降,并能诱导细胞凋亡,LDH释放量及细胞内活性氧和MDA含量明显增加;丹皮酚(12,25和50μmol.L-1)预处理1 h可提高细胞存活率,减少细胞凋亡、LDH释放量及细胞内活性氧和MDA含量。结论丹皮酚对H2O2诱导的PC12细胞凋亡具有抑制作用,该作用可能与其抗氧化作用有关。     

原花青素B2对H2O2诱导的星形胶质细胞氧化损伤和凋亡的保护作用及机制研究[①]

摘要：目的 本研究旨在探讨原花青素B2（proanthocyanidin B2, PC-B2）对过氧化氢（H2O2）诱导的小鼠星形胶质细胞（astrocytes, AS）氧化损伤和凋亡的保护作用及其机制。方法 利用C57BL/6新生小鼠（1-3 d）分离、培养AS,通过随机数字表法分为正常组、正常+PC-B2组（100 μg·mL-1的PC-B2处理24 h）、H2O2模型组（200 μmol·L-1的H2O2处理24 h）、H2O2+PC-B2组（200 μmol·L-1的H2O2与100 μg·mL-1的PC-B2共同处理24 h）;CCK-8法检测各组细胞存活率,LDH法进行细胞毒性检测;ELISA试剂盒检测各组细胞中MDA含量以及SOD、CAT和GSH-Px活力;TUNEL染色法检测各组细胞凋亡情况;RT-PCR和Western Blot分别检测AS中Bax、Bcl-2、Caspase-3、Akt/Stat3、p-Akt、p-stat3、Nrf2/HO-1的mRNA和蛋白表达水平。结果 PC-B2能够明显增强细胞活力,抑制AS凋亡。并且与H2O2模型组相比,PC-B2干预能够显著降低AS中LDH、MDA含量,提高SOD、CAT和GSH-Px活力,抑制Bax,caspase-3的mRNA和蛋白表达,上调Akt/Stat3、Bcl-2、Nrf2/HO-1的mRNA和蛋白表达。结论 PC-B2能够通过Akt/Stat3和Nrf2/HO-1途径增强AS抗氧化能力,减轻H2O2诱导的AS氧化损伤和凋亡。     

三氧化铬——硫酸氧化法制备1,3—二氯丙酮

以三氧化铬-硫酸为氧化剂,将1,3-二氯-2-丙醇(2)转化为1,3-二氯丙酮(1),产率83.6％。     

3-（3-羟基-1-甲基丙氧基）-1-丁醇和3-（3-羟基丁氧基）-1-丁醇的合成及其工艺改进

目的合成3-（3-羟基-1-甲基丙氧基）-1．丁醇（Ⅰ）和3-（3-羟基丁氧基）-1-丁醇（Ⅰ），并改进工艺提高产品纯度。方法以1，3-丁二醇为起始原料，通过硫酸催化双分子缩合、三苯甲基选择性保护、分离提纯、脱保护基4步反应得到目标化合物。结果与结论化合物Ⅰ的结构经。H．NMR13C-NMR谱确证，其含量经C-C测定，大于99．5％。化合物Ⅰ的纯度为90．0％，与文献相比纯度都有相应提高。     

1-甲基-1,2,3,4-四氢异喹啉的简易合成

目的制备1-甲基-1,2,3,4-四氢异喹啉。方法以苯乙胺为原料,经酰化反应得乙酰苯乙胺,在多聚磷酸的作用下环合得1-甲基-3,4-二氢异喹啉,经硼氢化钠还原得1-甲基-1,2,3,4-四氢异喹啉。结果反应总收率80%,比文献收率提高了10%,产物结构由1H-NMR光谱确证。结论经酰化、环合、还原三步反应制备1-甲基-1,2,3,4-四氢异喹啉的方法简单,原料便宜,处理容易,副产物较少。     

Potencies of vitamin D analogs, 1α‐hydroxyvitamin D3, 1α‐hydroxyvitamin D2 and 25‐hydroxyvitamin D3, in lowering cholesterol in hypercholesterolemic mice in vivo

Vitamin D₃ and the synthetic vitamin D analogs, 1α‐hydroxyvitamin D₃ [1α(OH)D₃], 1α‐hydroxyvitamin D₂ [1α(OH)D₂] and 25‐hydroxyvitamin D₃ [25(OH)D₃] were appraised for their vitamin D receptor (VDR) associated‐potencies as cholesterol lowering agents in mice in vivo. These precursors are activated in vivo: 1α(OH)D₃ and 1α(OH)D₂ are transformed by liver CYP2R1 and CYP27A1 to active VDR ligands, 1α,25‐dihydroxyvitamin D₃ [1,25(OH)₂D₃] and 1α,25‐dihydroxyvitamin D₂ [1,25(OH)₂D₂]_, respectively. 1α(OH)D₂ may also be activated by CYP24A1 to 1α,24‐dihydroxyvitamin D₂ [1,24(OH)₂D₂], another active VDR ligand. 25(OH)D₃, the metabolite formed via CYP2R1 and or CYP27A1 in liver from vitamin D₃, is activated by CYP27B1 in the kidney to 1,25(OH)₂D₃. In C57BL/6 mice fed the high fat/high cholesterol Western diet for 3 weeks, vitamin D analogs were administered every other day intraperitoneally during the last week of the diet. The rank order for cholesterol lowering, achieved via mouse liver small heterodimer partner (Shp) inhibition and increased cholesterol 7α‐hydroxylase (Cyp7a1) expression, was: 1.75 nmol/kg 1α(OH)D₃ > 1248 nmol/kg 25(OH)D₃ (dose ratio of 0.0014) > > 1625 nmol/kg vitamin D₃. Except for 1.21 nmol/kg 1α(OH)D₂ that failed to lower liver and plasma cholesterol contents, a significant negative correlation was observed between the liver concentration of 1,25(OH)₂D₃ formed from the precursors and liver cholesterol levels. The composite results show that vitamin D analogs 1α(OH)D₃ and 25(OH)D₃ exhibit cholesterol lowering properties upon activation to 1,25(OH)₂D₃: 1α(OH)D₃ is rapidly activated by liver enzymes and 25(OH)D₃ is slowly activated by renal Cyp27b1 in mouse.     

Synthesis and bioactivity of some new 1-tolyl-3-aryl-4-methylimidazole-2-thiones

Three series of new 1-(isomeric methyl)benzoyl-3-arylthioureas (1–3a–i) were prepared from 2-, 3-, and 4-methylbenzoyl chlorides via isothiocyanate formation followed by treatment with various substituted anilines. The base-catalyzed condensation of thioureas (1–3a–i) with acetone was carried out in the presence of bromine to afford the corresponding 1-(isomeric methyl) benzoyl-3-aryl-4-methyl-imidazole-2-thiones (4–6a–i) in good yield. Thioureas and the corresponding thiones were characterized by spectroscopic data and elemental analyses. The mass fragmentation pattern of thiones is also discussed. The thiones were evaluated for antibacterial, antifungal, and insecticidal activities and exhibit significant antibacterial activity and slight but not significant antifungal and insecticidal properties.     

Pharmacological characterization of A-131701, a novel α1-adrenoceptor antagonist selective for α1A- and α1D-compared to α1B-adrenoceptors

New compounds selective for α_1A-adrenoceptors in the prostate may offer enhanced efficacy for benign prostatic hyperplasia (BPH), with fewer side effects than current treatment. A-131701 (3-[2-((3aR,9bR)-cis-6-methoxy-2,3,3a,4,5,9b,hexahydro-[1H]-benz[e]isoindol-2-yl)ethyl]pyrido[3′,4′:4,5]thieno [3,2-d]pyrimidine-2,4(1H,3H)-dione), from a novel class of benz[e]isolindole pyridothienopyrimidines and pyridothienopyrazines, is selective for α_1a- and α_1d-adrenoceptors in radioligand binding studies (0.22 nM at α_1a-, 0.97 nM at α_1d-) compared to α_1b-sites (2.5 nM) and in isolated tissue bioassays (pA₂ values of 8.9–9.0 for α_1A-receptors in rat vas deferens or canine prostate strips, 9.1 at α_1D-sites (rat aorta)), compared to 7.9 at α_1B-sites (rat spleen). A-131701 also potently blocked radioligand binding to α₁-adrenoceptors in canine and human prostatic membranes, but was considerably weaker at α₂-adrenoceptors. In isoflurane-anesthetized dogs, A-131701 antagonized epinephrine-induced increases in intraurethral pressure (IUP) with a pseudo-pA₂ value of 8.17. In spontaneously hypertensive rats, A-131701 caused transient decreases in mean arterial blood pressure (MABP) and transient tachycardia. The area under the curve (AUC₀→₆₀ min) for the hypotensive response was dose-related, with a log index value for A-131701 of 5.33, suggesting a selectivity of >600-fold comparing IUP to MABP effects. In pentobarbital-anesthetized dogs, A-131701 was more potent in blocking phenylephrine (PHE)-induced increases in IUP (pseudo-pA₂ = 8.0) compared to concurrently measured MABP (pseudo-pA₂ = 7.2), or sixfold selective. Doses greater than 1,000 nmol/kg i.v. of A-131701 were required to lower blood pressure by 10 mm Hg in these dogs (pED₁₀ =. 5.57), indicating a uroselectivity ratio of >250, superior to doxazosin, terazosin, or tamsulosin. Thus, A-131701 is selective for α_1A- and α_1D- vs. α_1B-adrenoceptors in vitro, and prostatic function vs. blood pressure effects in vivo, which may provide therapeutic advantages in the treatment of BPH. Drug Dev. Res. 44:140–162, 1998. © 1998 Wiley-Liss, Inc.     

Conformational investigation of α, β-dehydropeptides

The crystal structure of Ac-Pro-ΔVal-NHCH₃ was examined to determine the influence of the α,β-dehydrovaline residue on the nature of peptide conformation. The peptide crystallizes from methanol-diethyl ether solution at 4° in needle-shaped form in orthorhombic space group P2₁2₁2₁ with a= 11.384(2) Å, b = 13.277(2) Å, c = 9.942(1) Å. V = 1502.7(4) ų Z = 4, D_m= 1.17 g cm^?3 and D_c=1.18 g cm^?3 The structure was solved by direct methods using SHELXS-86 and refined to an R value of 0.057 for 1922 observed reflections. The peptide is found to adopt a β-bend between the type I and the type III conformation with φ₁=?68.3(4)°, ψ₁=? 20.1(4)°, φ₂=?73.5(4)°= and Ψ₂=?14.1(4)°=. An intramolecular hydrogen bond between the carbonyl oxygen of ith residue and the NH of (i+ 3)th residue stabilizes the β-bend. An additional intermolecular N.,.O hydrogen bond joins molecules into infinite chains. In the literature described crystal structures of peptides having a single α,β-dehydroamino acid residue in the (i+ 2) position and forming a β-bend reveal a type II conformation.     

Effects of 4-nonylphenol on adipogenesis in 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells

Obesogens are a subset of endocrine disruptor chemicals (EDCs) that cause obesity. The typical EDC 4-nonylphenol (4-NP) has been identified as an obesogen. However, the in vitro effects of 4-NP on adipogenesis remain unclear. In this study, 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells (MSCs) were used to investigate the influence of 4-NP on adipogenesis. The differentiation protocols for 3T3-L1 preadipocytes and C3H/10T1/2 MSCs took 8 and 12 days, respectively, beginning at Day 0. In differentiated 3T3-L1 preadipocytes, 20 μM 4-NP decreased cell viability on Days 4 and 8. Exposure to 4-NP inhibited triglyceride (TG) accumulation and adipogenic marker expression on Days 0–8, but the inhibitory effects were weaker on Days 2–8. The protein expression of pSTAT3 or STAT3 decreased on Days 0–8 and 2–8. Conversely, 4-NP promoted TG accumulation and the adipogenic marker expression in C3H/10T1/2 adipocytes. The opposing effects were attributed to physiological differences between the two cell lines. The 3T3-L1 preadipocytes are dependent on mitotic clonal expansion (MCE) to drive differentiation, while C3H/10T1/2MSCs and human preadipocytes are not. Additionally, 4-NP downregulated β-catenin expression in C3H/10T1/2 adipocytes. Accordingly, we hypothesized that 4-NP promotes adipogenesis. The role of the canonical Wnt pathway in the promotion of adipogenesis by 4-NP requires further validation. This study provides new insights into the mechanisms and appropriate risk management of 4-NP.     

小檗碱与梓醇及其配伍对胰岛素抵抗3T3-L1脂肪细胞Glut-4、IRS-1、IRS-1 Ser307磷酸化蛋白表达的影响

目的：观察梓醇与小檗碱及其配伍对胰岛素抵抗3T3-L1脂肪细胞葡萄糖消耗及这一过程中葡萄糖转运子-4（Glut-4）、胰岛素受体底物-1（IRS-1）和胰岛素受体底物-1丝氨酸307（IRS-1Ser307）磷酸化蛋白表达的影响。方法：采用高糖联合高胰岛素诱导3T3-L1脂肪细胞产生胰岛素抵抗，分别给予小檗碱、梓醇、小檗碱＋梓醇、盐酸罗格列酮进行干预，以葡萄糖氧化酶法检测培养液中葡萄糖消耗量，以WesternBlot法检测蛋白的表达。结果：与模型组相比，小檗碱能增加培养液中葡萄糖的消耗（P〈0．01），但对Glut，4蛋白的表达无影响；梓醇、小檗碱＋梓醇均能显著增加培养液中葡萄糖的消耗（P〈0．01），并使细胞中Glut-4蛋白的表达增强（P〈0．05），且小檗碱＋梓醇组的效应优于梓醇组及小檗碱组；与模型组相比，小檗碱与梓醇及其配伍对IRS-1的表达没有显著性影响，但能降低IRS-1 Ser307磷酸化蛋白表达。结论：小檗碱、梓醇及其配伍能改善胰岛素抵抗3T3-L1脂肪细胞的胰岛素敏感性，其作用机制与罗格列酮不同。     

（3S-反式）-3-氨基-4-甲基-2-氧代-1-氮杂环丁烷磺酸的合成

目的:以L-苏氨酸为起始原料,合成(3S-反式)-3-氨基-4-甲基-2-氧代-1-氮杂环丁烷磺酸。方法:以L-苏氨酸为原料,经氨基保护,N-酰化,羟基保护,磺化,环合,脱保护6步反应,制得(3S-反式)-3-氨基-4-甲基-2-氧代-1-氮杂环丁基磺酸。结果:目标化合物经熔点测定,收率12.92%.结论:该法操作简洁,设备条件不苛刻,收率较佳。