Central role of Yes-associated protein and WW-domain-containing transcriptional co-activator with PDZ-binding motif in pancreatic cancer development

Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC.Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network.Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein(YAP) and WW-domaincontaining transcriptional co-activator with PDZ-binding motif(TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.

Wheat kinase TaSnRK2.4 forms a functional module with phosphatase TaPP2C01 and transcription factor TaABF2 to regulate drought response

SNF1-related protein kinase 2(SnRK2)family members are essential components of the plant abscisic acid(ABA)signaling pathway initiated by osmotic stress and triggering a drought stress response.This study characterized the molecular properties of TaSnRK2.4 and its function in mediating adaptation to drought in Triticum aestivum.Transcripts of TaSnRK2.4 were upregulated upon drought and ABA signaling and associated with drought-and ABA-responsive cis-elements ABRE and DRE,and MYB and MYC binding sites in the promoter as indicated by reporter GUS protein staining and activity driven by truncations of the promoter.Yeast two-hybrid,BiFC,and Co-IP assays indicated that TaSnRK2.4 protein interacts with TaPP2C01 and an ABF transcription factor(TF)TaABF2.The results suggested that TaSnRK2.4 forms a functional TaPP2C01-TaSnRK2.4-TaABF2 module with its upstream and downstream partners.Transgene analysis revealed that TaSnRK2.4 and TaABF2 positively regulate drought tolerance whereas TaPP2C01 acts negatively by modulating stomatal movement,osmotic adjustment,reactive oxygen species(ROS)homeostasis,and root morphology.Expression analysis,yeast one-hybrid,and transcriptional activation assays indicated that several osmotic stress-responsive genes,including TaSLAC1-4,TaP5CS3,TaSOD5,TaCAT1,and TaPIN4,are regulated by TaABF2.Transgene analysis verified their functions in positively regulating stomatal movement(TaSLAC1-4),proline accumulation(TaP5CS3),SOD activity(TaSOD5),CAT activity(TaCAT1),and root morphology(TaPIN4).There were high correlations between plant biomass and yield with module transcripts in a wheat variety panel cultivated under drought conditions in the field.Our findings provide insights into understanding plant drought response underlying the SnRK2 signaling pathway in common wheat.

Hepatitis C Virus non-structural 5A abrogates signal transducer and activator of transcription-1 nuclear translocation induced by IFN-α through dephosphorylation

AIM： To study the effect of Hepatitis C virus nonstructural 5A （HCV NSSA） on IFNα induced signal transducer and activator of transcription-1 （STAT1） phosphorylation and nuclear translocation.METHODS： Expression of STAT1 Tyr701 phosphorylation at different time points was confirmed by Western blot, and the time point when p-STAT1 expressed most, was taken as the IFN induction time for further studies. Immunocytochemistry was used to confirm the successful transient transfection of NS5A expression plasmid. Immunofluorescene was performed to observe if there was any difference in IFNα-induced STAT1 phosphorylation and nuclear translocation between HCV NSSA-expressed and non-HCV NSSA-expressed cells. Western blot was used to compare the phosphorylated STAT1 protein of the cells.RESULTS： Expression of HCV NS5A was found in the cytoplasm of pCNS5A-transfected Huh7 cells, but not in the PRC/ CMV transfected or non-transfected cells, STAT1 Tyr701 phosphorylation was found strongest in 30 min of IFN induction, STAT1 phosphorylation and nuclear import were much less in the presence of HCV NS5A protein in contrast to pRC/CMV-transfected and non-transfected cells under fluorescent microscopy, which was further confirmed by Western blot.CONCLUSION： HCV NSSA expression plasmid is successfully transfected into Huh7 cells and HCV NS5A protein is expressed in the cytoplasm of the cells. IFN-α is able to induce STAT1 phosphrylation and nuclear translocation, and this effect is inhibited by HCV NS5A protein, which might be another possible resistance mechanism to interferon alpha therapy.

Transcriptional activation function of hepatitis B virus Pre S1 protein in yeast

OBJECTIVE: To explore the feasibility of cloning of the hepatocyte receptor interacting with the Pre Slprotein of HBV by two-hybrid system.METHODS: Yeast expression plasmids encoding fusion proteins of full length or portions of Pre Sl ofHBV and DNA binding domain of yeast protein GAL4 were constructed and used to transform yeastreporter strain SFY526. Reporter gene product β-galactosidase activity was assayed as a measure oftranscriptional activation in yeast, Mammalian expression plasmid encoding fusion proteins of full lengthPre Sl and DNA binding domain of GAL4 was constructed and used to cotransfect hepatoma cell lineHuh-7 together with CAT reporter plasmid. Cell extracts were assayed for CAT activity by thin-layerchromatography.RESULTS: The fusion proteins of full length Pre Sl protein and GAL4 DNA binding domain presentedtranscriptional activation function in yeast. The transcription activating sequence was localized to the 21 to47 amino acids of Pre Sl protein. Fusion proteins of full length Pre Sl and GAL4 DNA binding domaindid not show transcriptional activation function in mammalian cells.CONCLUSIONS: The transcription activating sequence of HBV Pre Sl protein in yeast overlaps thehepatocyte receptor binding site. The transcriptional activation function of HBV Pre Sl protein in yeastmay prevent researchers from using yeast two-hybrid system to clone HBV receptor interacting with Pre Slprotein. However, the Pre Sl protein does not show transcriptional activation function in mammaliancells. Mammalian two-hybrid system may be a practical method to clone the HBV hepatocyte receptorinteracting with Pre Sl protein.

PDK1 promotes breast cancer progression by enhancing the stability and transcriptional activity of HIF-1α

Pyruvate dehydrogenase kinase 1(PDK1)phosphorylates the pyruvate dehydroge-nase complex,which inhibits its activity.Inhibiting pyruvate dehydrogenase complex inhibits the tricarboxylic acid cycle and the reprogramming of tumor cell metabolism to glycolysis,which plays an important role in tumor progression.This study aims to elucidate how PDK1 pro-motes breast cancer progression.We found that PDK1 was highly expressed in breast cancer tissues,and PDK1 knockdown reduced the proliferation,migration,and tumorigenicity of breast cancer cells and inhibited the HIF-1α(hypoxia-inducible factor 1α)pathway.Further investigation showed that PDK1 promoted the protein stability of HIF-1αby reducing the level of ubiquitination of HIF-1α.The HIF-1αprotein levels were dependent on PDK1 kinase activity.Furthermore,HIF-1αphosphorylation at serine 451 was detected in wild-type breast cancer cells but not in PDK1 knockout breast cancer cells.The phosphorylation of HIF-1αat Ser 451 stabilized its protein levels by inhibiting the interaction of HIF-1αwith von Hippel-Lindau and prolyl hydroxylase domain.We also found that PDK1 enhanced HIF-1αtranscriptional ac-tivity.In summary,PDK1 enhances HIF-1αprotein stability by phosphorylating HIF-1αat Ser451 and promotes HIF-1αtranscriptional activity by enhancing the binding of HIF-1αto P300.PDK1 and HIF-1αform a positive feedback loop to promote breast cancer progression.

Characterization of ribulose-1,5-bisphosphate carboxylase/oxygenase and transcriptional analysis of its related genes in Saccharina japonica(Laminariales,Phaeophyta)

Saccharina japonica is a common macroalga in sublittoral communities of cold seawater environments, and consequently may have highly efficient ribulose-1, 5-bisphosphate carboxylase/ oxygenase （Rubisco） activity for carbon assimilation. In our study, we cloned the full-length Rubisco gene from S.japonica （SJ-rbc）. It contained an open reading frame for a large subunit gene （SJ-rbcL） of 1 467 bp, a small subunit gene （SJ-rbcS） of 420 bp, and a SJ-rbcL/S intergenie spacer of 269 bp. The deduced peptides of SJ-rbcL and SJ-rbcS were 488 and 139 amino acids with theoretical molecular weights and isoelectric points of 53.97 kDa, 5.81 and 15,84 kDa, 4.71, respectively. After induction with 1 mmol/L isopropyl-β-D- thiogalactopyranoside for 5 h and purification by Ni2＋ affinity chromatography, electrophoresis and western blot detection demonstrated successful expression of the 55 kDa SJ-rbcL protein. Real-time quantitative PCR showed that the mRNA levels of SJ-rbcL in gametophytes increased when transferred into normal growth conditions and exhibited diurnal variations： increased expression during the day but suppressed expression at night. This observation implied that Rubisco played a role in normal gametophytic growth and development. In juvenile sporophytes, mRNA levels of SJ-rbcL, carbonic anhydrase, Calvin-Benson- Bassham cycle-related enzyme, and chloroplast light-harvesting protein were remarkably increased under continuous light irradiance. Similarly, expression of these genes was up-regulated under blue light irradiance at 350 umol/（m2.s）. Our results indicate that long-term white light and short-term blue light irradiance enhances juvenile sporophytic growth by synergistic effects of various photosynthetic elements.

Reactive oxygen species-induced activation of Yes-associated protein-1 through the c-Myc pathway is a therapeutic target in hepatocellular carcinoma

BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC.

CRISPR-assisted transcription activation by phaseseparation proteins

The clustered regularly interspaced short palindromic repeats(CRISPR)-Cas9 system has been widely used for genome engineering and transcriptional regulation in many different organisms.Current CRISPR-activation(CRISPRa)platforms often require multiple components because of inefficient transcriptional activation.Here,we fused different phase-separation proteins to dCas9-VPR(dCas9-VP64-P65-RTA)and observed robust increases in transcriptional activation efficiency.Notably,human NUP98(nucleoporin 98)and FUS(fused in sarcoma)IDR domains were best at enhancing dCas9-VPR activity,with dCas9-VPR-FUS IDR(VPRF)outperforming the other CRISPRa systems tested in this study in both activation efficiency and system simplicity.dCas9-VPRF overcomes the target strand bias and widens gRNA designing windows without affecting the off-target effect of dCas9-VPR.These findings demonstrate the feasibility of using phase-separation proteins to assist in the regulation of gene expression and support the broad appeal of the dCas9-VPRF system in basic and clinical applications.

低浓度氟化钠对人牙髓细胞的成骨/成牙本质分化的影响

目的探讨低浓度氟化钠对人牙髓细胞(human dental pulp cells,hDPCs)成骨/成牙本质分化的影响。方法本研究已通过单位伦理委员会审查批准。原代培养hDPCs,采用MTT法检测不同浓度氟化钠对hDPCs增殖的影响;选取合适浓度的氟化钠加入成骨/成牙本质分化诱导培养液中,对hDPCs进行体外诱导,通过茜素红染色检测hDPCs成骨/成牙本质分化能力的变化,RT⁃qPCR检测分化相关基因的mRNA表达;同时通过RT⁃qPCR和Western blot检测hDPCs成骨/成牙本质分化过程中内质网应激相关基因的表达。结果低浓度氟化钠(0.1 mmol/L)在体外可刺激hDPCs增殖,高浓度氟化钠(5~10 mmol/L)可抑制hDPCs增殖(P<0.05)。选取0.1 mmol/L氟化钠体外混合成骨/成牙本质分化诱导培养后hDPCs的茜素红染色增加,成骨/成牙本质分化相关基因牙本质涎磷蛋白(dentin sialophosphoprotein,DSPP)、骨涎蛋白(bone sialoprotein,BSP)和骨钙蛋白(osteocalcin,OCN)mRNA表达水平升高(P<0.05)。同时在此过程中RT⁃qPCR检测出mRNA水平hDPCs内质网应激相关基因:剪切x盒结合蛋白1(splicing x⁃box binding protein⁃1,sXBP1)、葡萄糖调节蛋白78(glucose⁃regulated protein 78,GRP78)以及活化转录因子4(activating transcription factor 4,ATF4)表达升高(P<0.05);Western blot检测出氟化钠混合成骨/成牙本质分化培养后细胞磷酸化真核起始因子⁃2α(phosphorylated eukary⁃otic initiation factor⁃2α,p⁃eIF2α)、磷酸化蛋白激酶样内质网激酶(phosphorylated the RNA⁃activated protein kinase⁃like ER⁃resident kinase,p⁃PERK)和ATF4蛋白表达增加(P<0.05)。结论低剂量氟化钠促进人牙髓细胞的成骨/成牙本质分化并伴有内质网应激水平的升高。

The Role and Mechanism of Unfolded Protein Response Pathway in Tumor Drug Resistance

In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS).As a signal mechanism that mitigates ERS in eukaryotic cells,the unfolded protein response(UPR)pathway can activate cells and tissues,regulating pathological activities in various cells,and maintaining ER homeostasis.It forms the most crucial adaptive and defensive mechanism for cells.However,under the continuous influence of chemotherapy drugs,the quantity of unfolded proteins and erroneous proteins produced by tumor cells significantly increases,surpassing the normal regulatory range of UPR.Consequently,ERS fails to function properly,fostering tumor cell proliferation and the development of drug resistance.This review delves into the study of three UPR pathways(PERK,IRE1,and ATF6),elucidating the mechanisms of drug resistance and research progress in the signal transduction pathway of UPR related to cancers.It provides a profound understanding of the role and relationship between UPR and anti-tumor drugs,offering a new direction for effective clinical treatment.

橄榄苦苷调节Hippo-YAP/TAZ信号通路对膝骨关节炎大鼠滑膜炎症的影响

目的探讨橄榄苦苷(OL)通过调节Yes相关蛋白(YAP)/转录共激活因子PDZ结合基序(TAZ)信号通路对膝骨关节炎(KOA)大鼠滑膜炎症的影响。方法采用改良的Hulth法构建KOA大鼠模型,并随机分为Model组、低剂量OL组(20 mg/kg)、高剂量OL组(40 mg/kg)、高剂量OL+VT103组(40 mg/kg+10 mg/kg YAP/TAZ抑制剂),每组12只,另取12只大鼠作为正常对照组(NC组)。观察各组大鼠的情况,Lequesne MG评分对各组大鼠行为学进行评估;ELISA试剂盒检测大鼠血清中肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)的表达;苏木精-伊红(HE)染色检测大鼠滑膜组织的病理损伤;qRT-PCR法检测滑膜组织中YAP和TAZ mRNA的表达;Western blot检测大鼠滑膜组织中YAP、磷酸化YAP(p-YAP)、磷酸化TAZ(p-TAZ)、TAZ、B细胞淋巴瘤/白血病-2相关X蛋白(Bax)蛋白表达。结果与NC组比较,Model组大鼠Lequesne MG评分升高、血清中TNF-α和IL-6的表达增加、YAP和TAZ mRNA表达增加、p-YAP/YAP、p-TAZ/TAZ、Bax蛋白表达升高(P<0.05);与Model组比较,低剂量、高剂量OL组大鼠Lequesne MG评分降低、血清中TNF-α和IL-6的表达减少、YAP和TAZ mRNA表达减少、p-YAP/YAP、p-TAZ/TAZ、Bax蛋白表达降低(P<0.05);VT103可明显减弱OL对KOA大鼠滑膜组织的保护作用(P<0.05)。结论OL可能通过激活YAP/TAZ信号通路减轻膝骨关节炎大鼠滑膜炎症。

仙茅苷介导PERK/ATF4/CHOP通路减轻UC大鼠肠黏膜病理改变的作用与机制探讨

目的 观察仙茅苷治疗溃疡性结肠炎(UC)大鼠的作用,并探讨其对蛋白激酶R样内质网激酶(PERK)/活化转录因子4(ATF4)/增强子结合蛋白同源蛋白(CHOP)通路的调控作用。方法 取61只SD大鼠以三硝基苯磺酸(TNBS)法诱导建立UC模型,按随机数字表分为仙茅苷低、中、高剂量组(25、50、100 mg/kg仙茅苷溶于生理盐水),美沙拉嗪组(500 mg/kg美沙拉嗪溶于生理盐水)、PERK抑制剂组(GSK2606414 1.0 mg/kg溶于生理盐水)、模型组(生理盐水),另取10只健康SD大鼠记为正常组(生理盐水),生理盐水体积均为1 ml/100 g大鼠体质量,均灌胃每天1次,连续10 d。给药结束后次日,评价疾病活动指数(DAI);气相色谱法(GC)测定两组大鼠5 h尿液中乳果糖(L)与甘露醇(M)排泄率(L/M)比值;双抗体夹心法测定血清糖皮质激素浓度,酶联免疫法测定血清白介素-6(IL-6)、干扰素(IFN-γ)、白介素-8(IL-8)和肿瘤坏死因子-α(TNF-α)水平;苏木素-伊红(HE)染色观察肠黏膜病理改变;实时-逆转录荧光定量聚合酶链反应(RT-qPCR)检测肠黏膜组织PERK、ATF4、CHOP、Bcl2关联X蛋白(Bax)、B淋巴细胞瘤-2(Bcl-2)信使核糖核酸(mRNA)表达;免疫印迹法(WB)检测肠黏膜组织PERK、ATF4、CHOP、Bax、Bcl-2蛋白表达及磷酸化PERK(p-PERK)水平。结果 肉眼和HE染色观察证实建模成功;与正常组比较,模型组L/M,DAI和肠黏膜病理评分,血清糖皮质激素浓度和血清IL-6、IFN-γ、IL-8和TNF-α水平,PERK、ATF4、CHOP、Bax mRNA与蛋白表达,p-PERK水平均升高(P<0.05),Bcl-2 mRNA及蛋白表达均下降(P<0.05);与模型组比较,仙茅苷3个剂量组、美沙拉嗪组、PERK抑制剂组L/M,DAI和肠黏膜病理评分,血清糖皮质激素浓度和血清IL-6、IFN-γIL-8和TNF-α水平,PERK、ATF4、CHOP、Bax mRNA与蛋白表达,p-PERK水平均下降(P<0.05),Bcl-2 mRNA及蛋白表达均升高(P<0.05);糖皮质激素浓度、PERK、ATF4、CHOP、Bax、Bcl-2 mRNA及蛋白表达,p-PERK水平仙茅苷低剂量组与美沙拉嗪组,仙茅苷中剂量组与美沙拉嗪组、PERK抑制剂组其它指标差异均无统计学意义(P>0.05),其余每2组比较差异均有统计学意义(P<0.05);模型组结肠黏膜病理严重改变,仙茅苷低剂量组有所减轻,仙茅苷中剂量组、美沙拉嗪组和PERK抑制剂组均明显减轻,仙茅苷高剂量组显著减轻。结论 仙茅苷可改善UC大鼠肠黏膜屏障功能、控制疾病活动度、减轻病理改变,推测与抑制PERK/ATF4/CHOP通路有关。

绝经后骨质疏松症患者外周血中GRP78和ATF4的表达水平及临床意义

目的探究绝经后骨质疏松症(postmenopausal osteoporosis,PMO)患者外周血中葡萄糖调节蛋白78(glucoseregulated protein 78,GRP78)和激活转录因子4(activating transcription factor 4,ATF4)的水平及临床意义。方法选取2018年12月—2021年5月石家庄市第三医院创伤骨科收治的96例PMO患者为PMO组,另选取同期96名体检健康的绝经女性为正常组。比较PM O组和正常组的一般资料;采用酶联免疫吸附法测定血清GR P78、ATF4水平;利用电化学发光免疫分析仪测定血清β-胶原特殊序列(β-Crosslaps)、Ⅰ型前胶原氨基端前肽(procollagenⅠtype N-terminal propeptide,PINP)水平;利用双能X线骨密度仪检测腰椎骨密度(bone mineral density,BMD);采用Pearson法分析PMO患者血清GRP78、ATF4水平与β-Crosslaps、PIN P、BM D的相关性及PMO患者血清GR P78表达水平与ATF4的相关性;用Logistic回归分析PMO发生的影响因素。结果PMO组患者腰臀比、BMD低于正常组(t=9.76、15.47,P均<0.001);血清GRP78、ATF4、β-Crosslaps、PINP水平高于正常组(t=18.32、16.81、8.15、14.84,P均<0.001);PMO患者血清GRP78、ATF4水平与β-Crosslaps、PINP均呈正相关(r=0.56、0.48、0.48、0.52,P<0.001、<0.001、<0.001、=0.006),与BMD呈负相关(r=-0.54、-0.44,P均<0.001);PMO患者血清GRP78水平与ATF4呈正相关(r=0.595,P<0.001);PINP、GRP78、β-Crosslaps、ATF4是影响PMO发生的危险因素(OR=2.518、2.672、2.271、2.336,P均<0.001),BMD是影响PMO发生的保护因素(OR=0.583,P<0.001)。结论PMO患者血清GRP78、ATF4水平较高,均与β-Crosslaps、PINP、BMD相关,GRP78、ATF4可能是诊治PMO的潜在靶标,测定血清GRP78、ATF4水平有助于临床防治PMO。

慢性疼痛中内质网应激机制的研究进展

慢性疼痛作为公共卫生难题,其发病机制复杂,涉及脊髓神经元兴奋、胶质细胞激活及受体活化等。药物治疗虽能缓解疼痛,但不良反应限制了其应用。研究表明,内质网应激在慢性疼痛中扮演关键角色,通过影响疼痛感受器敏感性、调控伤害信号传递、触发炎症反应及神经可塑性改变,加剧疼痛并促进其发展。本文综述了内质网蛋白激酶样内切割酶(PKR-like endoplasmic reticulum kinase,PERK)、内质网应激调节因子1α (inositol-requiring enzyme 1α, IRE1α)和激活转录因子6 (activating transcription factor 6, ATF6)等通路在内质网应激与慢性疼痛中的具体机制,旨在为其深入研究和临床应用提供科学支撑,并探讨尚未解决的问题及未来发展方向。

泛癌分析揭示SREK1在低级别胶质瘤中促进CD274表达

目的剪接调节谷氨酸和富赖氨酸的蛋白质1(SREK1)在多种肿瘤中的泛癌分析,揭示SREK1在泛癌中的作用。方法利用在线数据库GEPIA 2、TIMER 2.0、TISIDB和cBioPortal分析SREK1表达对肿瘤患者预后的影响、在低级别胶质瘤(LGG)肿瘤组织中的表达、遗传变异的特征及其表达对肿瘤组织中免疫细胞的浸润和免疫—肿瘤靶基因的相关性分析。结果LGG肿瘤组织中,SREK1表达与记忆B细胞、活化的CD4+T细胞、Th2细胞、中性粒细胞、NKT细胞以及单核细胞和CD56dimNK细胞的浸润存在相关性(P均<0.05)。SREK1与免疫—肿瘤靶基因如信号传导及转录激活蛋白3(STAT3)、Ⅰ型干扰素受体1(IFNAR1)、核受体亚家族3C组成员1(NR3C1)和表皮生长因子受体(EGFR)、表面抗原分化簇274(CD274)等表达在LGG中均呈正相关(P均<0.05)。结论SREK1是LGG患者的危险因子之一,可能通过促进CD274的表达来加剧LGG的进展。

药理激活p38/MAPK体外抗传染性喉气管炎病毒效应的检测

鸡传染性喉气管炎病毒(ILTV)是一种严重危害我国和世界养禽业的重要病原。本研究以ILTV-LJS09株感染的鸡LMH细胞系作为研究模型,对该病毒的全基因组转录谱分析,采用基因富集分析(GSEA)分析细胞中的信号通路。结果发现MAPK通路是ILTV感染LMH细胞后最显著激活的通路。进一步采用western blot鉴定,结果显示ILTV感染可以显著激活宿主细胞p38/MAPK信号通路。本研究同时采用脱氢紫堇碱(DHC)和佛波酯(PMA)作为p38/MAPK激活剂,采用特异性荧光定量PCR检测病毒基因组拷贝数,通过测定病毒的TCID_(50)检测病毒滴度,利用荧光定量PCR检测细胞中代谢相关基因的转录水平,使用高内涵成像技术结合Annexin V-FITC/碘化丙啶双染法检测细胞凋亡,从而探究药理激活p38/MAPK对ILTV感染的影响。病毒特异性荧光定量PCR检测结果显示,DHC和PMA均显著降低ILTV基因组的复制(P<0.05)。TCID_(50)测定结果显示,DHC和PMA还显著抑制ILTV感染性病毒粒子的增殖(P<0.05)。荧光定量PCR检测结果显示,无论DHC还是PMA对感染细胞代谢基因的总体转录水平均无明显影响。高内涵成像技术检测结果显示,DHC和PMA显著加剧ILTV感染细胞的凋亡(P<0.05)。综上所述,本研究结果显示DHC和PMA均能够在不影响感染细胞代谢基因表达的情况下,通过加剧ILTV感染细胞的凋亡有效抑制ILTV的感染。本研究在ILTV体外感染模型中证明药理激活p38/MAPK信号通路具有高效的抗病毒作用,为治疗ILTV的感染提供了新的思路,对其他疱疹病毒感染的防治研究也具有借鉴意义。

Slit引导配体2通过调控AMPK/SIRT1-FoxO1信号通路影响糖尿病小鼠视网膜血管损伤的机制研究

目的 探讨Slit引导配体2(SLIT2)是否通过调控腺苷单磷酸活化蛋白激酶(AMPK)/转录沉默信息调节因子1(SIRT1)-叉头盒蛋白O1(FoxO1)信号通路通过对糖尿病小鼠视网膜血管损伤的影响。方法 30只db/db小鼠随机分为DR组(db/db小鼠)、DR+阴性对照载体组(DR+sh-NC组)和DR+sh-SLIT2组,每组10只。另选10只db/m小鼠为对照组。DR+sh-NC组和DR+sh-SLIT2组麻醉后分别在双眼玻璃体腔内注射sh-SLIT2的腺相关病毒(AAV)载体。眼底荧光血管造影(FFA)和苏木精伊红染色观察视网膜血管病变;酶联免疫吸附测定检测血清白细胞介素-6(IL-6),肿瘤坏死因子α(TNF-α)和血管内皮生长因子(VEGF)的水平,荧光定量PCR检测SLIT2 mRNA表达;Western blot检测视网膜组织SLIT2、AMPK、SIRT1、FoxO1蛋白水平。结果 与对照组相比,DR组、DR+sh-NC组、DR+sh-SLIT2组血糖、每日饮水量、每日排尿量、食物摄入量及体质量均明显升高(P<0.05);与对照组相比,DR组视网膜存在血管病变及病理损伤,SLIT2 mRNA及蛋白表达、IL-6、TNF-α和VEGF水平,FoxO1蛋白水平均明显升高(P<0.05),AMPK、SIRT1蛋白水平均明显降低(P<0.05);与DR+sh-NC组相比,DR+sh-SLIT2组的视网膜血管病变及病理损伤明显减轻,SLIT2 mRNA及蛋白表达、IL-6、TNF-α和VEGF水平,FoxO1蛋白水平均明显降低(P<0.05),AMPK、SIRT1蛋白水平均明显升高(P<0.05)。结论 沉默SLIT2表达显著改善糖尿病小鼠视网膜血管损伤及炎症水平,这可能是通过调控AMPK/SIRT1-FoxO1信号通路发挥作用的。

EDEM1通过稳定ATF6促进颅内动脉瘤发展的作用研究

目的:探究内质网降解增强α-甘露糖苷酶样蛋白1(EDEM1)和激活转录因子6(ATF6)在颅内动脉瘤(IA)发展中的作用。方法:纳入40例颅内动脉瘤患者和40例健康受试者,收集两组人群血清,通过ELISA检测ATF6水平。根据Hunt-Hess分级和Fisher分级将IA患者分为:轻度疾病组、中度疾病组和重度疾病组,比较3组患者血清中ATF6水平。将si-EDEM1和si-NC转染至HCAECs细胞,分组为si-EDEM1组和si-NC组,采用western blot检测两组细胞EDEM1和ATF6蛋白表达水平,CCK-8法检测两组细胞增殖水平。通过免疫共沉淀检测EDEM1和ATF6的相互作用情况。将si-ATF6和si-NC转染至HCAECs细胞,分组为si-ATF6组和si-NC组,采用Western blot检测两组细胞EDEM1和ATF6蛋白表达水平,CCK-8法检测两组细胞增殖水平。结果:与健康受试者相比,颅内动脉瘤患者血清中ATF6水平升高(P<0.05)。ATF6水平在轻度疾病组、中度疾病组和重度疾病组中依次递增(P<0.05)。与si-NC组相比,si-EDEM1组细胞EDEM1和ATF6蛋白表达水平降低,细胞增殖水平降低(P<0.05)。EDEM1和ATF6存在相互作用。与si-NC组相比,si-ATF6组细胞ATF6蛋白表达水平降低,细胞增殖水平降低(P<0.05)。结论:EDEM1通过稳定ATF6促进动脉内皮细胞增殖,与IA的恶化相关。

EDEM1通过稳定ATF6促进颅内动脉瘤发展的作用

目的 探究内质网降解增强α-甘露糖苷酶样蛋白1 (EDEM1)和激活转录因子6 (ATF6)在颅内动脉瘤(IA)发展中的作用。方法 纳入40例IA患者和40例健康受试者,收集两组人群血清,通过ELISA检测ATF6水平。根据Hunt-Hess分级和Fisher分级将IA患者分为:轻度疾病组、中度疾病组和重度疾病组,比较3组患者血清中ATF6水平。将si-EDEM1和si-NC转染至HCAECs细胞,分组为si-EDEM1组和si-NC组,采用Western blot检测两组细胞EDEM1和ATF6蛋白表达水平,CCK-8法检测两组细胞增殖水平。通过免疫共沉淀检测EDEM1和ATF6的相互作用情况。将si-ATF6和si-NC转染至HCAECs细胞,分组为si-ATF6组和si-NC组,采用Western blot检测两组细胞EDEM1和ATF6蛋白表达水平,CCK-8法检测两组细胞增殖水平。结果 与健康受试者相比,IA患者血清中ATF6水平升高(P<0.05)。ATF6水平在轻度疾病组、中度疾病组和重度疾病组中依次递增(P<0.05)。与si-NC组相比,si-EDEM1组细胞EDEM1和ATF6蛋白表达水平降低,细胞增殖水平降低,(P <0.05)。EDEM1和ATF6存在相互作用。与si-NC组相比,si-ATF6组细胞ATF6蛋白表达水平降低,细胞增殖水平降低(P<0.05)。结论 EDEM1通过稳定ATF6促进动脉内皮细胞增殖,与IA疾病恶化相关。

经后增殖方含药血清对超排卵大鼠卵巢颗粒细胞GDF9表达及凋亡的调控机制

【目的】观察益气血法经后增殖方含药血清对超排卵大鼠卵巢颗粒细胞生长分化因子9(GDF9)表达及凋亡的调控机制。【方法】制备超排卵大鼠血清(空白血清)和经后增殖方灌胃的超排卵大鼠血清(含药血清)。建立控制性超排卵(COH)大鼠模型,收集卵巢颗粒细胞。实验分为5组:空白血清组,含药血清组,含药血清+SB203580[p38丝裂原活化蛋白激酶(p38MAPK)抑制剂]组,含药血清+PDTC[核转录因子κB(NF-κB)抑制剂]组,含药血清+SB203580+PDTC组。采用实时定量聚合酶链反应(qRT-PCR)法检测p38MAPK、酪蛋白激酶2(CK2)、核转录因子κB抑制因子α(IκBα)、NF-κB、GDF9 mRNA表达水平,蛋白免疫印迹(Western Blot)法检测GDF9蛋白表达水平,脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测卵巢颗粒细胞凋亡。【结果】经后增殖方含药血清降低COH大鼠卵巢颗粒细胞的p38MAPK和NF-κB mRNA表达,升高CK2和IκBαmRNA表达,提高GDF9 mRNA和蛋白的表达水平,降低卵巢颗粒细胞的凋亡率。单独添加p38MAPK抑制剂SB203580与单独添加NF-κB抑制剂PDTC均能促进GDF9 mRNA和蛋白表达、降低卵巢颗粒细胞凋亡率。【结论】益气血法经后增殖方含药血清可促进超排卵大鼠卵巢颗粒细胞GDF9表达,抑制卵巢颗粒细胞凋亡,其机制可能与调控p38MAPK和NF-κB双信号通路基因表达有关。