乳酸杆菌对子宫内膜上皮细胞增殖的影响

目的研究乳酸杆菌对子宫内膜上皮细胞增殖的影响。方法以内蒙古地区68名健康生育期女性人群作为研究对象,取阴道分泌物,经条件培养基分离纯化乳酸杆菌,通过染色、酶触反应、产H2O2等试验确定其生物学性质,通过16sRNA基因扩增及测序对乳酸杆菌进行分类。将不同浓度(10、102、103和104个/mL)优势乳酸杆菌与子宫内膜上皮细胞共培养12、24、36和48 h,采用CCK-8法检测乳酸杆菌对子宫内膜上皮细胞增殖作用的影响,以确定乳酸杆菌对子宫内膜上皮细胞作用的最适浓度和时间。结果经过分离纯化得到141株乳酸杆菌,草酸铵结晶紫染色呈紫色,为革兰阳性菌,所有菌落均能产生H2O2,但产H2O2能力有差别。经16sRNA基因扩增及测序共分为6种乳酸杆菌,其中卷曲乳杆菌(L. crispatus)、格氏乳杆菌(L. asseri)和阴道乳杆菌(L. vaginalis)为内蒙古女性人群阴道中优势乳酸杆菌菌属,分别占54. 61%、24. 82%和12. 06%;不同浓度L. crispatus均能促进子宫内膜上皮细胞增殖,且乳酸杆菌浓度103个/mL、作用36 h时,子宫内膜上皮细胞增殖最显著,增殖率可达93. 10%。结论乳酸杆菌可促进子宫内膜上皮细胞的增殖,为乳酸杆菌促进子宫内膜局部的损伤修复提供了理论依据。     

EB病毒抑制小肠上皮细胞增殖的ERK1/2途径分析

目的分析EB病毒(EB virus,EBV)抑制小肠上皮细胞增殖的机理,初步探讨EBV导致腹泻的病理机制。方法应用EBV作用于小肠上皮细胞,作用后0、12、24、36和48 h,采用MTT法检测细胞的增殖情况,Western blot法检测细胞MAPK(磷酸化的ERK1/2、JNK、p38)通路的表达情况。结果经EBV作用36及48 h的小肠上皮细胞存活率较24及12 h显著降低,并显著低于0 h(P 0. 05);磷酸化ERK1/2的表达在36和48 h最低,显著低于其他3个时间点(P 0. 05)。结论 EBV可抑制小肠上皮细胞的增殖,且通过抑制ERK1/2磷酸化途径实现。本实验为进一步研究EBV导致腹泻的发病机理提供了参考。     

ERK1/2抑制对沙门菌侵袭小鼠胃癌细胞后小鼠β-防御素-2表达的影响

目的探讨ERK1/2抑制对沙门菌侵袭小鼠胃癌(mouse forestomach carcinoma,MFC)细胞后小鼠β-防御素-2(mouseβ-defensin-2,m BD-2)表达的影响及作用机制。方法采用RNA干扰的方法抑制MFC细胞中ERK1/2的表达,并经G418筛选稳定细胞株,经RT-PCR和Western blot法检测ERK1/2基因的抑制效率。用10~3个/ml的沙门菌对干扰组及对照组(未转染)的MFC细胞分别作用4、8及12 h,通过Western blot法检测m BD-2蛋白表达及Rsk~(90)的磷酸化水平。同时采用MTT法检测沙门菌作用两组MFC细胞12、24及48 h时的生长情况。结果RT-PCR和Western blot法检测结果表明,ERK1/2基因抑制效果显著。沙门菌作用MFC细胞后4、8和12 h后,各时间点间干扰组细胞中m BD-2蛋白表达及Rsk~(90)蛋白磷酸化水平差异无统计学意义(P0.05),且均显著低于各时间点的对照组(P0.05)。沙门菌作用12和24 h,干扰组细胞的抑制率明显高于对照组(P0.05),作用48 h时,两组细胞的抑制率差异无统计学意义(P0.05),细胞几乎全部死亡,且干扰组细胞抑制率的增加速度较快,作用24 h时已达97.7%。结论ERK1/2抑制可明显降低沙门菌侵袭MFC后m BD-2的表达水平,表明ERK1/2可调控m BD-2的表达。     

MgF2包覆对正极材料LiNi1/3Co1/3Mn1/3O2性能的影响

通过浸渍法在正极材料LiNi1/3Co1/3Mn1/3O2的表面包覆MgF2,通过XRD、SEM、交流阻抗（EIS）分析、充放电测试研究了不同量MgF2包覆对LiNi1/3Co1/3Mn1/3O2正极材料的结构与电化学性能的影响。结果表明,MgF2以非晶态形式包覆于LiNi1/3Co1/3Mn1/3O2材料颗粒的表面,当包覆量为3%（物质的量分数,下同）时,三元正极材料具有优良的电化学性能,在3.0~4.6 V充放电范围内0.1C充放电倍率下,首次放电比容量为196.3 mA·h/g,1C循环50次后容量保持率为95.7%,55 ℃高温下1C循环50次后容量保持率为93.3%。     

丝氨酸/精氨酸蛋白特异激酶2基因真核表达质粒的构建及其对HeLa细胞增殖和凋亡的影响

目的构建小鼠丝氨酸/精氨酸蛋白特异激酶2(serine/arginine-rich protein specific kinase 2,SRPK2)基因真核表达质粒,建立稳定过表达SRPK2的He La细胞系,并探讨SRPK2过表达对He La细胞增殖和凋亡的影响。方法利用RT-PCR从小鼠睾丸组织中扩增SRPK2基因,与p3×Flag-CMV-14质粒连接,构建重组真核表达质粒p3×Flag-CMV-14-SRPK2,转染He La细胞,通过G418筛选获得稳定转染细胞系。采用RT-PCR检测稳定转染He La细胞系中SRPK2基因的转录,Western blot检测SRPK2的表达;MTT法和流式细胞术分别检测SRPK2过表达对He La细胞增殖和凋亡的影响。结果菌落PCR、双酶切及DNA测序表明重组真核表达质粒p3×Flag-CMV-14-SRPK2构建正确;RT-PCR和Western blot分析表明SRPK2基因在He La细胞中稳定过表达;p3×Flag-CMV-14-SRPK2稳定转染组细胞增殖活力明显高于p3×Flag-CMV-14转染组和未转染组(P0.05),细胞凋亡率明显低于上述两组(P0.05)。结论成功构建了SRPK2基因的真核表达质粒,建立了稳定过表达SRPK2的He La细胞系,SRPK2过表达可增强He La细胞的增殖活力,而抑制其凋亡。     

丹参酮ⅡA对大鼠脊髓损伤后星形胶质细胞增殖的MAPK通路的影响

目的探讨丹参酮ⅡA(tanshinoneⅡA,TⅡA)对大鼠脊髓损伤(spinal cord injury,SCI)后星形胶质细胞增殖的MAPK通路的影响。方法建立大鼠SCI模型,获得星形胶质细胞,培养14 d后,采用免疫荧光法检测星形胶质细胞中胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的表达;MTT法选择TⅡA抑制星形胶质细胞生长的最适浓度和时间;Western blot法检测MAPK通路各蛋白的磷酸化情况。结果星形胶质细胞中有GFAP特异性表达;TⅡA抑制星形胶质细胞生长的最适浓度为15μg/mL,最适作用时间为36 h;15μg/m L TⅡA作用0和4 h,星形胶质细胞中p-JNK高于8和12 h,ERK1/2和p38无变化。结论 TⅡA主要通过JNK依赖性途径对星形胶质细胞的生长进行调控。     

Apg-2过表达对BaF3-MIGR1及稳定表达BCR/ABL的BaF3-P210细胞增殖的影响

目的探讨热休克蛋白Apg-2过表达对小鼠pMIGR1空载体感染细胞BaF3-MIGR1和BCR/ABL转化细胞BaF3-P210(简称BP210)增殖的影响。方法构建pIERS2-EGFP-Apg-2真核表达质粒,电穿孔转染BaF3-MIGR1和BP210细胞,经G418筛选稳定表达细胞株,分别用RT-PCR和Western blot鉴定Apg-2的表达。采用Am-Blue法和流式细胞仪(FCM)检测Apg-2过表达对BaF3-MIGR1和BP210细胞增殖的影响,光镜观察细胞形态变化。结果pIERS2-EGFP-Apg-2真核表达质粒构建正确,转染细胞后筛选到稳定过表达Apg-2的BaF3-MIGR1-Apg-2和BP210-Apg-2细胞株,BaF3-MIGR1-Apg-2细胞的增殖速度明显低于BaF3-MIGR1细胞,BP210-Apg-2细胞比BP210细胞增殖加快。光镜下可见Apg-2过表达的两种细胞形态发生变化,瑞氏染色可见细胞核增多。结论Apg-2能够促进BCR/ABL阳性细胞的增殖,可能与慢性粒细胞白血病的发生发展相关。     

电解液浸泡对锂离子电池正极材料LiNi1/3Co1/3Mn1/3O2的影响

主要考察了电解液浸泡对Li Ni1/3Co1/3Mn1/3O2粉料的影响,通过扫描电镜(SEM)观察了不同条件下粉体的形貌,采用X射线衍射仪及拉曼光谱仪表征晶体的结构,并将样品组装成电池,比较了不同条件处理下样品的首次放电及倍率性能。结果表明,电解液浸泡对Li Ni1/3Co1/3Mn1/3O2的形貌和晶体结构影响较小,但对粉体的电阻率和电池的容量有较大影响,而且随着浸泡温度的升高,其粉体电阻率和放电比容量均下降。     

Li[Ni1/2Mn1/2]O2的制备及电化学性能研究

介绍了一种采用前驱体碳酸盐共沉淀法制备锂离子电池正极材料Li[Ni1/2Mn1/2]O2的工艺路线。通过对样品进行X射线衍射(XRD)测试,可知产品具有类似钴酸锂的层状结构。通过对产品进行扫描电镜(SEM)观察可以看出,产品具有规则的球形形貌,且粒径在5~10μm;电化学测试表明,材料的首次放电比容量大于170 mA.h/g,循环20次后容量保持率大于98%。     

牦牛肝脏蛋白对人肝癌HepG2细胞增殖及凋亡的影响

目的检测牦牛肝蛋白BGP对人肝癌HepG2细胞增殖及凋亡的影响,并探讨其体外抗癌活性。方法用不同浓度的BGP分别作用于人肝癌HepG2细胞,作为实验组,同时设未处理细胞对照组和空白对照组,采用MTT法检测BGP(25、50和100 mg/L)作用HepG2细胞12、24、36和48 h对细胞增殖活性的影响,并于倒置显微镜下观察细胞形态变化;采用流式细胞仪检测BGP(25、50、75、100 mg/L)作用HepG2细胞24 h,对细胞周期及凋亡的影响。结果不同浓度的BGP均可抑制HepG2细胞增殖,与未处理细胞对照组相比,差异均有统计学意义(P<0.05),其中100 mg/L BGP作用48 h,对HepG2细胞抑制率最高(94.99%)。各浓度BGP实验组HepG2细胞形态发生明显改变,细胞间隙加大,细胞间连接不牢固,胞内颗粒增多,呈现生长受阻状态,甚至有细胞脱落,细胞数目减少,其中100 mg/L BGP作用48 h,凋亡细胞明显增多。不同浓度BGP作用HepG2细胞24 h后,均可不同程度抑制HepG2细胞生长并诱导细胞凋亡;与未处理细胞对照组相比,S期细胞比例明显升高(除25 mg/L BGP实验组),G0/G1期和G2/M期细胞比例明显下降,差异均有统计学意义(P<0.05)。结论牦牛肝蛋白BGP可抑制HepG2细胞增殖,并促进凋亡,具有明显的体外抗肝癌活性。     

Lactoferrin Deficiency Impairs Proliferation of Satellite Cells via Downregulating the ERK1/2 Signaling Pathway

Lactoferrin (Ltf), a naturally active glycoprotein, possesses anti-inflammatory, anti-microbial, anti-tumor, and immunomodulatory activities. Many published studies have indicated that Ltf modulates the proliferation of stem cells. However, the role of Ltf in the proliferation of satellite cells, an important cell type in muscle regeneration, has not yet been reported. Here, by using Ltf systemic knockout mice, we illustrate the role of Ltf in skeletal muscle. Results shows that Ltf deficiency impaired proliferation of satellite cells (SCs) and the regenerative capability of skeletal muscle. Mechanistic studies showed that ERK1/2 phosphorylation was significantly downregulated after Ltf deletion in SCs. Simultaneously, the cell cycle-related proteins cyclin D and CDK4 were significantly downregulated. Intervention with exogenous recombinant lactoferrin (R-Ltf) at a concentration of 1000 μg/mL promoted proliferation of SCs. In addition, intraperitoneal injection of Ltf effectively ameliorated the skeletal muscle of mice injured by 1.2% BaCl₂ solution. Our results suggest a protective effect of Ltf in the repair of skeletal muscle damage. Ltf holds promise as a novel therapeutic agent for skeletal muscle injuries.     

MCFA alleviate H2O2-induced oxidative stress in AML12 cells via the ERK1/2/Nrf2 pathway

Oxidative stress is an important factor in the occurrence and development of liver disease. Medium-chain fatty acids (MCFAs) have potential antioxidant function, whereas the exact underlying mechanism of MCFA in oxidative injury of hepatocytes remains unclear. In our present study, three different MCFAs, 8-carbon octanoic acid (OA), 10-carbon capric acid (CA), and 12-carbon lauric acid (LA), have been performed to observe their protective action for hepatocyte under the H₂O₂ challenge. The result showed that MCFA treatment significantly increased the cell viability, T-AOC, and expression of antioxidant-related genes in AML12 cells under oxidative stress condition, and reduced reactive oxygen species (ROS) production. Moreover, MCFA treatment significantly increased the protein expression of Nrf2 and the phosphorylation level of ERK1/2; LA treatment significantly promoted the Nrf2 nuclear translocation. With a further test, the rescue ability of MCFA was blocked by treating with the ERK inhibitor U0126. Overall, our data suggested that MCFA treatment has positive impact on protecting AML12 cells against oxidative stress through ERK1/2/Nrf2 pathway.     

A Specific Oligodeoxynucleotide Promotes the Differentiation of Osteoblasts via ERK and p38 MAPK Pathways

A specific oligodeoxynucleotide (ODN), ODN MT01, was found to have positive effects on the proliferation and activation of the osteoblast-like cell line MG 63. In this study, the detailed signaling pathways in which ODN MT01 promoted the differentiation of osteoblasts were systematically examined. ODN MT01 enhanced the expression of osteogenic marker genes, such as osteocalcin and type I collagen. Furthermore, ODN MT01 activated Runx2 phosphorylation via ERK1/2 mitogen-activated protein kinase (MAPK) and p38 MAPK. Consistently, ODN MT01 induced up-regulation of osteocalcin, alkaline phosphatase (ALP) and type I collagen, which was inhibited by pre-treatment with the ERK1/2 inhibitor U0126 and the p38 inhibitor SB203580. These results suggest that the ERK1/2 and p38 MAPK pathways, as well as Runx2 activation, are involved in ODN MT01-induced up-regulation of osteocalcin, type I collagen and the activity of ALP in MG 63 cells.     

Airway Smooth Muscle Cell Mitochondria Damage and Mitophagy in COPD via ERK1/2 MAPK

Chronic obstructive pulmonary disease (COPD) is characterized by irreversible deterioration of the airway wall. Cigarette smoking is the major trigger, and in vitro studies showed that cigarette smoke extract (CSE) induced mitophagy in airway epithelial cells via oxidative stress, but this mechanism was not studied in airway smooth muscle cells (ASMCs). Primary ASMCs isolated from COPD patients or non-disease donors were investigated for CSE-induced remodeling and mitochondria structure. Proteins were assessed by Western blots for remodeling: collagen type-I, α-smooth muscle actin (α-SMA) and fibronectin; autophagy: beclin-1, protein62 (p62), light chain (LC)3A/B; mitochondria activity: mitochondrially encoded cytochrome c oxidase II & -IV (MTCO2, MTCO4), peroxisome proliferator activated receptor gamma coactivator 1α (PGC-1α); lysosomes: early endosome antigen 1, lysosome activated membrane protein 1; and cell signaling: extracellular signal regulated kinase (ERK1/2). Lysotracker and Mitotracker were used to monitor mitochondria morphology and organelle co-localization. Compared with controls, untreated COPD ASMCs showed lower collagen type-I and α-SMA expressions, but increased fibronectin levels. CSE further downregulated collagen type-I and α-SMA expression, but upregulated fibronectin. CSE decreased PGC-1α, MTCO2, and MTCO4, but increased beclin-1, p62, and LC3. CSE upregulated mitophagy and lysosomes activity via ERK1/2 phosphorylation. In vitro, cigarette smoke induced the deterioration of ASMCs, which might explain the tissue loss and structural remodeling in COPD bronchi. The results suggest that preventing exceeded mitophagy in ASMCs might present a novel therapeutic target for COPD.     

Nec-1 Enhances Shikonin-Induced Apoptosis in Leukemia Cells by Inhibition of RIP-1 and ERK1/2

Necrostatin-1 (Nec-1) inhibits necroptosis by allosterically inhibiting the kinase activity of receptor-interacting protein 1 (RIP1), which plays a critical role in necroptosis. RIP1 is a crucial adaptor kinase involved in the activation of NF-κB, production of reactive oxygen species (ROS) and the phosphorylation of mitogen activated protein kinases (MAPKs). NF-κB, ROS and MAPKs all play important roles in apoptotic signaling. Nec-1 was regarded as having no effect on apoptosis. Here, we report that Nec-1 increased the rate of nuclear condensation and caspases activation induced by a low concentration of shikonin (SHK) in HL60, K562 and primary leukemia cells. siRNA-mediated knockdown of RIP1 significantly enhanced shikonin-induced apoptosis in K562 and HL60 cells. Shikonin treatment alone could slightly inhibit the phosphorylation of ERK1/2 in leukemia cells, and the inhibitory effect on ERK1/2 was significantly augmented by Nec-1. We also found that Nec-1 could inhibit NF-κB p65 translocation to the nucleus at a later stage of SHK treatment. In conclusion, we found that Nec-1 can promote shikonin-induced apoptosis in leukemia cells. The mechanism by which Nec-1 sensitizes shikonin-induced apoptosis appears to be the inhibition of RIP1 kinase-dependent phosphorylation of ERK1/2. To our knowledge, this is the first study to document Nec-1 sensitizes cancer cells to apoptosis.     

FOXC1蛋白基因shRNA干扰质粒对胃癌SGC-7901细胞增殖的影响

目的探讨FOXC1蛋白基因RNA干扰质粒对胃癌SGC-7901细胞增殖的影响。方法采用RT-PCR及Westernblot法检测SGC-7901细胞和胃黏膜上皮细胞GES-1中FOXC1基因mRNA的转录水平和蛋白的表达水平。构建3个FOXC1基因shRNA真核表达质粒pshRNA-FOXC1a、pshRNA-FOXC1b、pshRNA-FOXC1c,分别转染SGC-7901细胞,并设pGenesil-1空质粒转染组和未转染的细胞对照组,RT-PCR及Western blot法分别检测转染细胞中FOXC1基因mRNA的转录水平和蛋白的表达水平;MTT法检测转染细胞的增殖活力;流式细胞术检测转染细胞的细胞周期。结果 SGC-7901细胞中FOXC1基因mRNA的转录水平及蛋白的表达水平均显著高于GES-1细胞(P<0.05)。pshRNA-FOXC1a组、pshRNA-FOXC1b组和pshRNA-FOXC1c组SGC-7901细胞中FOXC1基因mRNA的转录水平和蛋白的表达水平均显著低于pGenesil-1组和SGC-7901组(P<0.01);细胞增殖抑制率显著高于pGensil-1组(P<0.05)。处于G1、G2期的细胞比例显著高于SGC-7901组(P<0.01),S期细胞比例显著低于SGC-7901组(P<0.01)。结论成功构建了FOXC1蛋白基因shRNA真核表达质粒。FOXC1在胃癌细胞SGC-7901中呈高表达,抑制其表达后,细胞周期被阻滞在G1～G2期,细胞增殖受到抑制。     

Plectin Downregulation Inhibits Migration and Suppresses Epithelial Mesenchymal Transformation of Hepatocellular Carcinoma Cells via ERK1/2 Signaling

Plectin, as a cytoskeleton-related protein, is involved in various physiological and pathological processes of many cell types. Studies have found that plectin affects cancer cell invasion and metastasis, but the exact mechanism is not fully understood. In this study, we aim to investigate the role of plectin in the migration of hepatocellular carcinoma (HCC) cells and explore its relevant molecular mechanism. Herein, we found that the expression of plectin in HCC tissue and cells was significantly increased compared with normal liver tissue and cells. After downregulation of plectin, the migration ability of HCC cells was significantly lower than that of the control group. Moreover, the expression of E-cadherin was upregulated and the expression of N-cadherin and vimentin was downregulated, suggesting that plectin downregulation suppresses epithelial mesenchymal transformation (EMT) of HCC cells. Mechanically, we found that plectin downregulation repressed the extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. Activation of ERK1/2 recovered the plectin downregulation-inhibited migration and EMT of HCC cells. Taken together, our results demonstrate that downregulation of plectin inhibits HCC cell migration and EMT through ERK1/2 signaling, which provides a novel prognostic biomarker and potential therapeutic target for HCC.     

IL-20 Activates ERK1/2 and Suppresses Splicing of X-Box Protein-1 in Intestinal Epithelial Cells but Does Not Improve Pathology in Acute or Chronic Models of Colitis

The cytokine Interleukin (IL)-20 belongs to the IL-10 superfamily. IL-20 levels are reported to increase in the intestines of Ulcerative Colitis (UC) patients, however not much is known about its effects on intestinal epithelial cells. Here, we investigated the influence of IL-20 on intestinal epithelial cell lines and primary intestinal organoid cultures. By using chemical-induced (dextran sodium sulphate; DSS) colitis and a spontaneous model of colitis (Winnie mice), we assess whether recombinant IL-20 treatment is beneficial in reducing/improving pathology. Following stimulation with IL-20, intestinal primary organoids from wild-type and Winnie mice increased the expression of ERK1/2. However, this was lost when cells were differentiated into secretory goblet cells. Importantly, IL-20 treatment significantly reduced endoplasmic reticulum (ER) stress, as measured by spliced-XBP1 in epithelial cells, and this effect was lost in the goblet cells. IL-20 treatment in vivo in the DSS and Winnie models had minimal effects on pathology, but a decrease in macrophage activation was noted. Taken together, these data suggest a possible, but subtle role of IL-20 on epithelial cells in vivo. The therapeutic potential of IL-20 could be harnessed by the development of a targeted therapy or combination therapy to improve the healing of the mucosal barrier.     

ERK1/2 Activity Is Critical for the Outcome of Ischemic Stroke

Ischemic disorders are the leading cause of death worldwide. The extracellular signal-regulated kinases 1 and 2 (ERK1/2) are thought to affect the outcome of ischemic stroke. However, it is under debate whether activation or inhibition of ERK1/2 is beneficial. In this study, we report that the ubiquitous overexpression of wild-type ERK2 in mice (ERK2^wt) is detrimental after transient occlusion of the middle cerebral artery (tMCAO), as it led to a massive increase in infarct volume and neurological deficits by increasing blood–brain barrier (BBB) leakiness, inflammation, and the number of apoptotic neurons. To compare ERK1/2 activation and inhibition side-by-side, we also used mice with ubiquitous overexpression of the Raf-kinase inhibitor protein (RKIP^wt) and its phosphorylation-deficient mutant RKIP^S153A, known inhibitors of the ERK1/2 signaling cascade. RKIP^wt and RKIP^S153A attenuated ischemia-induced damages, in particular via anti-inflammatory signaling. Taken together, our data suggest that stimulation of the Raf/MEK/ERK1/2-cascade is severely detrimental and its inhibition is rather protective. Thus, a tight control of the ERK1/2 signaling is essential for the outcome in response to ischemic stroke.