Experimental study on the effect of cryoablation on lung cancer mice based on MAPK/ERK signaling pathway

Objective:To study the regulatory effect of cryoablation on MAPK/ERK signaling pathway in mice with lung adenocarcinoma.Methods:Lewis mouse lung adenocarcinoma cell line was used to establish subcutaneous transplanted tumor model in C57BL/6 mice.Ten mice were randomly divided into two groups:sham operation group and cryoablation group,with 5 mice in each group.The cryoablation group was treated with double circulation-rewarming ablation,and the sham operation group was treated with incision and suture at the transplanted tumor.The tumor tissues were taken 14 days after operation.Detect the effect of cryoablation on MAPK/ERK pathway related proteins by Western blot,such as KRAS,RAF1,MEK1,ERK1/2,P-RAF1,P-MEK1,P-ERK1/2.The expression of KRAS gene was further verified by qRt-PCR.Results:Compared with the sham operation group,the phosphorylated proteins P-RAF1,P-MEK1 and P-ERK1/2 in tumor tissue after cryoablation were decreased(P<0.05),and the key molecule KRAS in MAPK/ERK pathway was decreased in protein and gene expression(P<0.05).Conclusion:Cryoablation can negatively regulate MAPK/ERK signaling pathway by down-regulating KRas expression.

Timosaponin AⅢ induces drug-metabolizing enzymes by activating constitutive androstane receptor (CAR) via dephosphorylation of the EGFR signaling pathway

The current study aimed to assess the effect of timosaponin AⅢ(T-AⅢ)on drug-metabolizing enzymes during anticancer therapy.The in vivo experiments were conducted on nude and ICR mice.Following a 24-day administration of T-AⅢ,the nude mice exhibited an induction of CYP2B10,MDR1,and CYP3A11 expression in the liver tissues.In the ICR mice,the expression levels of CYP2B10 and MDR1 increased after a three-day T-AⅢ administration.The in vitro assessments with HepG2 cells revealed that T-AⅢ induced the expression of CYP2B6,MDR1,and CYP3A4,along with constitutive androstane receptor(CAR)activation.Treatment with CAR siRNA reversed the T-AⅢ-induced increases in CYP2B6 and CYP3A4 expression.Furthermore,other CAR target genes also showed a significant increase in the expression.The up-regulation of murine CAR was observed in the liver tissues of both nude and ICR mice.Subsequent findings demonstrated that T-AⅢ activated CAR by inhibiting ERK1/2 phosphorylation,with this effect being partially reversed by the ERK activator t-BHQ.Inhibition of the ERK1/2 signaling pathway was also observed in vivo.Additionally,T-AⅢ inhibited the phosphorylation of EGFR at Tyr1173 and Tyr845,and suppressed EGF-induced phosphorylation of EGFR,ERK,and CAR.In the nude mice,T-AⅢ also inhibited EGFR phosphorylation.These results collectively indicate that T-AⅢ is a novel CAR activator through inhibition of the EGFR pathway.

NIMA related kinase 2 promotes gastric cancer cell proliferation via ERK/MAPK signaling

BACKGROUND NIMA related kinase 2(NEK2) is closely related to mitosis, and it is currently considered to be over-expressed frequently in many poorly prognostic cancers.However, the effect of the up-regulated NEK2 on cellular signaling in tumors,such as gastric cancer(GC), is con-fusing.AIM To determine the role of the up-regulation of NEK2 in GC.METHODS To investigate the pathological significance of NEK2 in GC, the expression pattern of NEK2 in GC was investigated based on the 'Oncomain' database and compared between 30 pairs of cancer samples and adjacent tissues. The coexpression of NEK2 and ERK in GC was analyzed using The Cancer Genome Atlas(TCGA) database and confirmed in clinical samples by quantitative realtime PCR(qRT-PCR), and the survival curve was also plotted. Western blot or qRT-PCR was used to analyze the effect of NEK2 on the phosphorylation levels of ERK and c-JUN in two GC cell lines(BGC823 and SGC7901) with NEK2 overexpression, and the expression of the downstream effector cyclin D1.Furthermore, CCK8, EdU incorporation assay, and flow cytometry were used to detect the proliferative ability of BGC823 and SGC7901 cells with stably silenced ERK.RESULTS NEK2 was significantly up-regulated in human GC tissues. ERK was significantly associated with NEK2 expression in human clinical specimens, and combined overexpression of NEK2 and ERK potentially forecasted a poor prognosis andsurvival in GC patients. NEK2 knockdown in GC cells inhibited ERK and c-JUN phosphory-lation and reduced the transcription of cyclin D1. More interestingly,NEK2 can rescue the inhibition of cellular viability, proliferation, and cell cycle progression due to ERK knockdown.CONCLUSION Our results indicate that NEK2 plays a carcinogenic role in the malignant proliferation of GC cells via the ERK/MAPK signaling, which may be important for treatment and improving patient survival.

MEK/ERK signaling pathway in apoptosis of SW620 cell line and inhibition effect of resveratrol

Objective:To study the involvement of MAPK MEK/ERK signaling transduction pathway in the apoptosis process of SW620 tumor cell line and the inhibition effect of resveratrol.Methods:SW620 cell lines were divided into 5 groups,namely,control group.PD98059 group,low-dose resveratrol group,mid-dose resveratrol group and high-dose resveratrol group.The inhibition rate of cell proliferation was detected by MTT method.The expression of apoptotic molecules and MEK/ERK signaling pathway related proteins were assayed by realtime PCR and Western blotting.Results:Compared with control group,the proliferation of cells treated with resveratrol was significantly inhibited.In the case of apoptotic molecules,the expression of Bax,Caspase 3 and Caspase 9 was increased significantly while the expression of anti-apoptotic molecule Bcl2 was decreased significantly in resveratrol groups with a dosedependent manner.In the case of molecules in MEK/ERK signaling pathway,the expression of Ras,Raf,MEK and ERKl/2 was decreased significantly in resveratrol groups with a dose-dependent manner.Conclusions:PD98059 and resveratrol can effectively inhibit the proliferation of SW620 through inhibiting the MEK/ERK signaling pathway.

Endogenous hydrogen sulfide and ERK1/2-STAT3 signaling pathway may participate in the association between homocysteine and hypertension

Background Homocysteine(Hcy)is a risk factor for hypertension,although the mechanisms are poorly understood.Methods We first explored the relationship between Hcy levels and blood pressure(BP)by analyzing the clinical data of primary hypertensive patients admitted to our hospital.Secondly,we explored a rat model to study the effect of Hcy on blood pressure and the role of H2S.An hyperhomocysteinemia(HHcy)rat model was induced to explore the effect of Hcy on blood pressure and the possible mechanism.We carried out tissue histology,extraction and examination of RNA and protein.Finally,we conducted cell experiments to determine a likely mechanism through renin-angiotensin-aldosterone system(RAAS)and extracellular signal-regulated kinase 1/2(ERK1/2)signaling pathway.Results In primary hypertensive inpatients with HHcy,blood pressure was significantly higher as compared with inpatient counterparts lacking HHcy.In the rat model,blood pressure of the Wistar rats was significantly increased with increases in serum Hcy levels and decreased after folate treatment.Angiotensin converting enzyme 1(ACE1)expression in the Wistar Hcy group was enhanced comparing to controls,but was decreased in the Wistar folate group.Angiotensin II receptor type 1(AGTR1)levels in the kidney tissue increased in the Wistar folate group.Both serum H2S and kidney cystathionineγ-lyase decreased with elevated levels of serum Hcy.In vitro,increased concentrations and treatment times for Hcy were associated with increased expression of collagen type 1 and AGTR1.This dose and time dependent response was also observed for p-STAT3 and p-ERK1/2 expression.Conclusion Endogenous H2S might mediate the process of altered blood pressure in response to changes in serum Hcy levels,in a process that is partly dependent on activated RAAS and ERK1/2-STAT3 signaling pathway.

Immunoregulatory polysaccharides from Apocynum venetum L.flowers stimulate phagocytosis and cytokine expression via activating the NF-κB/MAPK signaling pathways in RAW264.7 cells

Two immunomodulatory polysaccharides(Vp2a-Ⅱ and Vp3) were isolated and identified from Apocynum venetum L. flowers, and their innate immune-stimulating functions and working mechanisms were evaluated in RAW264.7 cells. Both the level of released nitric oxide(NO) and expression of inducible nitric oxide synthase(iNOS) m RNA were significantly enhanced in the RAW264.7 macrophages cells treated by Vp2a-Ⅱ and Vp3. Vp2a-Ⅱ(100–800 μg/m L) and Vp3(400 μg/mL) could significantly increase the phagocytic activity of RAW264.7 cells and the secretion and m RNA expression of TNF-α and IL-6 in a concentrationdependent manner through affecting mitogen-activated protein kinase(MAPK) activity and nuclear factor κB(NF-κB) nuclear translocation. Vp2a-Ⅱ might activate the MAPK signaling pathways and induce the nuclear translocation of NF-κB p65, whilst Vp3 likely activated the NF-κB and MAPK signaling pathways without influencing the p38 MAPK route.

Effect of the Tiaobufeishen decoction on Caveolin-1-p38 MAPK signaling pathway and mechanism of improving the tracheobronchomalacia in chronic obstructive pulmonary disease

Objective: Reliving the rela ti onship of the Caveolin-1-p38 MAPK signaling pathway and COPD tr acheob ronchomalacia, and resea rch the mechanism of Tiaobufeishen decoc tion imp rove the regression of the weasand cartilage cells. Methods: Flow cytometry was used to analyze the apoptosis rate to determine the optimal concentration of Tiaobufeishen decoction and CSE, CCK8 assay was used to dete rmine the op ti mal concent ration of P38-MAPK specific inhibitor. The COPD cell model was created by tracheal chondrocyte which dispose by optimal concent ration CSE, then add the IL-1P set up the chond rocyte degene ration model, use the method of toluidine blue staining and immunohistochemical authenticate degeneration of cartilage. This research included control group, model group, model-Tiaobufeishen group, model-blocker group. When the model was set up succeed, add the Tiaobufeishen decoction and P38-MAPK blocke r in the model-Tiaobufeishen and model-blocke r gr oups, r espectively. Weste rn Blot was used to detect the exp ression of caveolin-1 and p-p38 in the chond rocyte. RT-PCR was used to detect the expression of MMP3 and caveolin-1 in the matrix. Results: The cell activity was not influence by the concentration of Tiaobufeishen decoction and blocker, the concentration of the CSE model was moderation. Compared with control group, the level of caveolin-1, p38MAPK, MMP3 in the model group was significant increase, moreover, the result of toluidine blue staining and immunohistochemical methods show that the chond rocyte has obvious reg ression. The exp ression of caveolin-1, p38MAPK, and MMP3 have significant decrease than the control group, and the reduction of chondrocyte degeneration. Conclusion: The caveolin-1-p38MAPK signaling pathway play an important role in the morbidity of the tracheobronchomalacia. Tiaobufeishen decoction could decrease the exp ression of the caveolin-1, p-p38, MMP3, inhibit the activa tion of the caveolin-1-p38MAPK signaling pathway, therefore, it can improve the tracheobronchomalacia.

Acupuncture at Back-Shu point improves insomnia by reducing inflammation and inhibiting the ERK/NF-κB signaling pathway

BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use is prone to drug resistance and other adverse reactions.Acupuncture has a good curative effect and unique advantages in the treatment of insomnia.AIM To explore the molecular mechanism of acupuncture at Back-Shu point for the treatment of insomnia.METHODS We first prepared a rat model of insomnia,and then carried out acupuncture for 7 consecutive days.After treatment,the sleep time and general behavior of the rats were determined.The Morris water maze test was used to assess the learning ability and spatial memory ability of the rats.The expression levels of inflammatory cytokines in serum and the hippocampus were detected by ELISA.qRTPCR was used to detect the mRNA expression changes in the ERK/NF-κB signaling pathway.Western blot and immunohistochemistry were carried out to evaluate the protein expression levels of RAF-1,MEK-2,ERK1/2 and NF-κB.RESULTS Acupuncture can prolong sleep duration,and improve mental state,activity,diet volume,learning ability and spatial memory.In addition,acupuncture increased the release of 1L-1β,1L-6 and TNF-αin serum and the hippocampus and inhibited the mRNA and protein expression of the ERK/NF-κB signaling pathway.CONCLUSION These findings suggest that acupuncture at Back-Shu point can inhibit the ERK/NF-κB signaling pathway and treat insomnia by increasing the release of inflammatory cytokines in the hippocampus.

The role of ERK1/2 signaling pathway in coronary microembolization-induced rat myocardial inflammation and injury

Objectives In this work,we explore the effect of atorvastatin on myocardial apoptosis and caspase-8 acti- vation after coronary microembolization(CME) in rats. Methods Fifty rats were randomly divided into five groups; the coronary microembolization(CME) group,the sham-operated (sham) control group,the gastric lavage control group, the atorvastatin lavage group,and the caspasse-8 inhibitor (N-acetyl-Ile-Glu-Thr-Asp-CHO,abbreviated as CHO) group,with 10 rats for each group.A microembolization ball was injected through the left ventricle for constructing the CME model.Animals in the sham control group were given an injection of physiological saline instead of the microembolization ball.Seven days before the operation,the atorvastatin group underwent gastric lavage with 20 mg/kg of atorvastatin once a day.Gastric lavage control animals underwent gastric lavage with an equivalent dose of physiological saline instead of the atorvastatin.Animals in the CHO group were given an intraperitoneal injection of 10 mg/kg of CHO 30 min before the operation.Six hours after the operation,cardiac ultrasonic detection was conducted on each group to measure the cardiac function indexes.TUNEL(Terminal-deoxynucleoitidyl transferase mediated dUTP nick end labeling) assays were used to measure myocardial apoptosis,and western blots were used to quantify the expression levels of activated caspase-3 and -8.Results(1) The echocardiographic parameters showed that,compared to the sham control animals,the left ventricular ejection fraction(LVEF) of the CME group was significantly decreased(P【0.05).In addition, cardiac sonography revealed a decrease in the left ventricular shortening fraction(FS) and cardiac output(CO), but an increase in the left ventricular end-diastolic dimension (LVEDd).Compared to the CME group,the atorvastatin and CHO groups exhibited significantly improved cardiac function (P【0.05).(2) When compared with the sham control,the myocardical apoptotic rate of the CME group,as well as the levels of activated caspase-3 and-8,increased significantly (P【0.05).The myocardial apoptotic rate,as well as the levels of activated caspase-3 and caspase-8 in the atorvastatin and CHO groups,decreased significandy(P【0.05) in comparison to the CME group.Conclusions The atorvastatin pretreatment clearly suppressed post-CME myocardial apoptosis and improved cardiac function.The most likely mechanism for these effects is the blockade of the myocardial death receptor -mediated apoptosis pathway.

Irisin Attenuates Osteoarthritis by Inhibiting Apoptosis of Osteocytes Through Activating Erk Signaling Pathway

Osteoarthritis(OA)is an inflammatory disease involving the joints that is prevalent in the global aging population.The purpose of this study is to determine whether irisin can attenuate osteoarthritis(OA)progression in anterior cruciate ligament transection(ACLT)mice models and the mechanism of irisin therapy effect on OA by increase the resistance of apoptosis in MLO-Y4 cells induced by mechanical stretch in vitro.Methods For in vivo study,3-month-old male C57BL/6 J mice were randomized to three groups,sham-operated,anterior cruciate ligament transection(ACLT)-operated treated with vehicle,and ACLT-operated treated with irisin by intraperitoneal injection once a week.Cartilage erosion was observed by HE staining.Osteoarthritis Research Society International(OARSI)scores were evaluated according to the safranin O stai-ning.The microstructure of tibia cortical bone,trabecular bone,and subchondral bone was analyzed by micro-CT and the bone histomorphometry has been administrated including mineral apposition rate(MAR).Edu staining and cck-8 were used for the detection of the proliferation of MLO-Y4 cells.For mechanical stress,cells were seeded on the collagen-I coated chamber subjected with a peak biaxial stretch of 20%at 1 Hz for 16 hours to induce apoptosis.Flow cytometry was used for the detection of apoptosis and cell cycle.TUNNEL was used for staining the apoptotic cells and rt-PCR was applied for quantifying the expression of mRNA such as Bax,Bcl-2,SOST,c-myc,Opg.Western blot was utilized to confirm the mechanism of how irisin decrease the osteocyte apoptosis.Results In vivo,irisin can attenuate articular cartilage degeneration.Irisin maintains the proportion of hyaline cartilage and calcified cartilage and keep fewer cartilage erosions in ACLT-operated mice.For immunohistochemical(IHC)staining,irisin reduced the expression of caspase3,Bax and matrix metalloproteinase-13 in both cartilage and subchondral bone.Irisin-treated ACLT group shows higher Trabecular number(Tb.N)and bone volume fraction(BV/TV)compared to the vehicle-treated ACLT group.In vitro, irisin significantly increased the proliferation of MLO-Y4 cells detected by Edu and Ki67 staining,and irisin can protect the cells from both mechanical stretchinduced apoptosis detected by FITC-PI flow cytometry and maintain the cell activity by regulating the expression of Bax,Bcl-2,and c-myc.Transcriptome sequencing shows that irisin significantly activates the MAPK signaling pathway and we confirm the result by western blot:irisin effectively activates the Erk signaling pathway through phosphorylation and has a certain activation effect on p38 signaling pathway,no activation was observed for FAK signaling pathway.Conclusions Irisin can attenuate the progression of OA by decrease the apoptosis of osteocyte,which can improve the microarchitecture of subchondral bone.Erk pathway activation plays an important role in reducing the apoptosis of osteocyte.

BcSDR1 is involved in regulation of glucose transport and cAMP and MAPK signaling pathways in Botrytis cinerea

Botrytis cinerea is a typical necrotrophic pathogenic fungus that causes severe diseases in a wide range of plant species, leading to significant economic losses. Our previous study showed that BcSDR1 positively regulates growth,development, and pathogenicity of B. cinerea. However, the regulation mechanism of BcSDR1 and the relationship between BcSDR1 and cAMP and MAPK signaling pathways are not well understood. In this study, transcriptome data showed that BcSDR1 is involved in glucose transmembrane transport, signal transduction, secondary metabolism, and other biological processes. BcSDR1 mutant(BCt41) showed remarkably weak sensitivity to cAMP and MAPK signaling pathways specific inhibitors, SQ22536 and U0126, and significantly decreased cAMP content. The key genes of cAMP and MAPK signaling pathways, BcGB1, BcBTP1, BcBOS1, BcRAS1, and BcBMP3 were significantly upregulated,whereas BcPLC1, BcBCG1, BcCDC4, BcSAK1, BcATF1, and BcBAP1 were significantly downregulated(P<0.05).BcSDR1 was obviously upregulated in BcBCG2, BcBCG3, BcPKA1, and BcPKAR RNA interference(RNAi) mutants, but significantly downregulated in BcPKA2, BcBMP1, and BcBMP3 RNAi mutants. Thus, BcBCG2, BcBCG3, BcPKA1, and BcPKAR negatively regulate BcSDR1 expression, whereas BcPKA2, BcBMP1, and BcBMP3 positively regulate BcSDR1expression.

Maleylated-BSA induces TNF-α production through the ERK and NF-κB signaling pathways in murine RAW264.7 macrophages

Ligands for macrophage scavenger receptors are reported to induce a wide range of host cell responses, including the production of inflammatory cytokines;however, the underlying mechanisms have not yet been fully understood and which remain obscure. In this study, we have examined the effect of maleylated bovine serum albumin (maleylated-BSA), a well-known ligand of the scavenger receptor, on the murine macrophage cell line RAW264.7. Maleylated-BSA strongly induced the production of tumor necrosis factor-α (TNF-α) and induced phosphorylation of extracellular signal-regulated kinase (ERK) and NF-kB p65. We also observed that maleylated-BSA-induced TNF-α production was blocked by the ERK inhibitor U0126. Together, these data demonstrates that maleylated-BSA- induced production of TNF-α requires the ERK/NF-κB signaling cascade in murine RAW- 264.7 macrophages.

To investigate the effects of butylphthalide on reducing neuronal apoptosis in rats with cerebral infarction by inhibiting the JNK/P38 MAPK signaling pathway

Objective:To investigate the effects of butylphthalide on reducing neuronal apoptosis in rats with cerebral infarction by inhibiting the JNK/P38 MAPK signaling pathway.Methods:Forty-eight SD male rats were divided into DZ group(control group),CI group(model group)and NBP group(butylphthalide group).Rats in CI group and NBP group were used to establish cerebral infarction models.NBP group used NBP.The solution(80 mg/(kg?d))was administered orally,and the remaining two groups were administered with the same volume of peanut oil.After 14 consecutive days of treatment,the Zea Longa score was used to evaluate the neurological function of DZ,CI and NBP rats.Scoring,TTC staining was used to observe the cerebral infarction volume of rats in DZ group,CI group and NBP group,HE staining was used to observe the pathological morphology of brain tissue in DZ group,CI group and NBP group.Neuronal apoptosis,Western blot was used to detect the expression of p-JNK and p-p38MAPK in brain tissues of DZ group,CI group and NBP group.Results:The neurological function of the rats in the CI group was higher than that in the DZ group,and the difference was statistically significant(P<0.05).The neurological function score of the rats in the NBP group was reduced compared with the CI group,and the difference was statistically significant(P<0.05).The cerebral infarction volume in the group was 35.56%higher than that in the DZ group,and the difference was statistically significant(P<0.05).The minor infarct volume in the NBP group was 21.59%,which was less than that in the CI group,and the difference was statistically significant(P<0.05).Nerve cells are neatly sorted,with a large number.The gap between blood vessels and interstitial tissue in the CI group is enlarged,the cells are severely contracted,and the neuron structure is incomplete.Compared with the CI group,the NBP group has reduced neuron contraction and increased number;The dead nerve cells were brown.The apoptosis rate of nerve cells in the CI group was 79.65%higher than that in the DZ group was 5.82%.The difference was statistically significant(P<0.05).The nerve cell apoptosis rate in the NBP group was 30.23%.Compared with CI group,the difference was statistically significant(P<0.05);Western blot results showed that p-JNK and p-p38MAPK protein expression in CI group was higher than that in DZ group,and the difference was statistically significant(P<0.05).The levels of p-JNK and p-p38MAPK proteins in the NBP group were lower than those in the CI group.There was statistically significant(P<0.05).Conclusion:Butylphthalide can improve neurological damage,reduce apoptotic nerve cells,and reduce infarct volume in rats with cerebral infarction,which is related to the inhibition of JNK/P38 MAPK pathway expression.

VEGFR2 mediated RAS/MAPK signaling pathway to explore the mechanism of Bushen Antai Granule in the treatment of recurrent abortion

Objective:To investigate the effect of Bushen Antai Granule on the mRNA and protein expression of Ras protein/mitogen activated protein kinase mediated by vascular endothelial growth factor receptor 2 with small interference RNA interference.Methods:Method to construct the placenta microvascular endothelial cells,and the preparation of kidney fetus granule drug-containing serum,select the best drug-containing serum concentration,it can be divided into normal group,the serum siRNA-NC normal serum group,drug serum,siRNA normal serum group,siRNA drug serum group,using real-time fluorescent quantitative PCR,Western blotting,immunofluorescence test respectively the RAS/MAPK mRNA and protein expression.Results:Results there was no significant difference in Ras and MAPK mRNA and protein expression between the normal group and the negative control group(P>0.05).The mRNA and protein expressions of Ras and MAPK in the drug serum group were significantly higher than those in the normal serum group(P<0.01).Ras and MAPK mRNA and protein expression were significantly decreased in siRNA1 normal serum group compared with normal serum group(P<0.01).Ras,MAPK mRNA and protein expression in siRNA1 drug serum group were significantly different from that in siRNA1 normal serum group(P<0.01).Conclusion:Conclusion The therapeutic effect of Bushen Antai Granule on recurrent abortion may be realized by upregulation of RAS/MAPK mRNA and protein expression.

Substrate Stiffness Affects Endothelial Cell Junctions and MAPK Signaling Pathway

Vascular homeostasis is critical for maintaining normal vascular structure and function. Aging is an irreversible trigger of vascular sclerosis, which causes structural and functional damage to blood vessels, leading to severe atherosclerosis. Endothelial cells (ECs) can respond to mechanical stimuli from the extracellular matrix, causing disruption of endothelial barrier function and activating signaling pathways to regulate cellular behavior under pathological conditions. In this paper, we investigated the effect of substrate stiffness on endothelial cell junctions, and the activation of mitogen-activated protein kinase (MAPK) signaling pathways. An in vitro stiffness model was established using polyacrylamide hydrogels of 1 kPa, 20 kPa and 100 kPa. By transcriptome analysis, we found that the cell-cell junction, cadherin binding, cytoskeleton and classical signaling pathways such as MAPK and Rho GTPase of endothelial cells were regulated by substrate stiffness. The expression of cell junction-related molecules TJP1, TJP2, JAM3 and JCAD was also found to be reduced at higher stiffness. The MAPK signaling pathway-related molecules MAP2K3, MAP2K7, MAP3K3, MAP3K6, MAPK3, MAPK7 were upregulated with increased stiffness. qRT-PCR analysis showed that the gene expression of JCAD was reduced with increased stiffness. Immunofluorescence staining of VE-cadherin indicated that the total fluorescence level of VE-cadherin decreased significantly with increased stiffness, and stiffness impaired the cell-cell junction with increased punctuation and discontinuity. Western blotting analysis confirmed that the protein expression ratio of pp38MAPK/p38MAPK increased with stiffness. Our research suggested that substrate stiffness played an important role in regulating endothelial cell integrity and MAPK signaling pathway.

鼻咽癌中Period2下调ERK/MAPK磷酸化水平的机制

目的探讨生物钟基因Period2在鼻咽癌中下调ERK/MAPK磷酸化水平的分子机制。方法用慢病毒对细胞进行感染,构建细胞系。采用Label-free蛋白质组学检测方法对PER2蛋白表达进行验证。采用不同浓度的ERK通路激活剂Ceramide C6干预各组细胞,MTT检测各组细胞的增殖能力,筛选最佳药物浓度和作用时间。采用ERK通路激活剂Ceramide C6干预细胞,正常对照组采用等剂量药物溶剂进行处理,分为6组。Western blot检测各组细胞PER2、ERK、p38MAPK、p-ERK、p-p38MAPK蛋白的表达。流式细胞术检测细胞周期,Transwell实验检测各组细胞侵袭能力,进一步明确PER2调控ERK、MAPK磷酸化的机制。用免疫组化检测PER2、p-ERK在人体鼻咽癌样本中的表达,并分析PER2、p-ERK与鼻咽癌临床特点的相关性。结果蛋白质组学检测结果示PER2过表达组的PER2蛋白表达明显高于阴性病毒对照组和空白对照组(P<0.05)。Top 20差异蛋白显示MAPK3在PER2过表达组和对照组差异有统计学意义(P<0.05)。MTT实验结果:不同药物浓度处理后,根据每组细胞抑制率,得出最佳的药物作用浓度10μmol/L,最佳处理时间24 h。WB结果显示PER2过表达下调p-ERK、p-p38MAPK蛋白表达,ERK通路激活剂Ceramide C6干预后,在PER2-OE组中ERK、p38MAPK蛋白水平无明显变化,但p-ERK、p-p38MAPK蛋白表达水平上调,干预前后差异有统计学意义(P<0.01)。细胞周期实验结果显示:ERK通路激活剂Ceramide C6干预各组细胞后,使细胞在G1期的比例明显增加,而在G2期数量减少。Transwell实验结果显示PER2过表达抑制细胞侵袭能力,此种现象不能被磷酸激酶逆转。在鼻咽癌组织、鼻咽部黏膜中PER2蛋白、p-ERK蛋白表达阳性率差异有统计学意义(P<0.05)。PER2蛋白表达与肿瘤的T分期相关(P<0.05)。在鼻咽癌组织中PER2蛋白与p-ERK蛋白表达相关(P<0.05)。结论PER2过表达下调ERK/MAPK磷酸化水平,可能不是直接作用于ERK和p38MAPK的磷酸化位点,而是与调控ERK和p38MAPK的关键节点有关。鼻咽癌组织中PER2蛋白呈低表达,p-ERK蛋白呈高表达,两者相关,并且与肿瘤的发生、发展关系密切。

丹参多糖经MAPK/ERK信号轴抑制对肺癌细胞A549增殖、迁移和凋亡的影响

目的 探讨丹参多糖经丝裂原激活蛋白激酶(MAPK)/细胞外信号调节激酶(ERK)信号轴抑制对肺癌细胞A549增殖、迁移和凋亡的影响。方法 体外培养A549细胞,用不同质量浓度(0,1,2,4,8,16,32,64 mg/mL)丹参多糖干预48 h后,确定丹参多糖的半数抑制浓度(IC50);将A549细胞分为对照组、高剂量组、中剂量组和低剂量组(分别以0,8,4,2 mg/mL丹参多糖干预),以及抑制剂组(40μmol/L PD 98059)。采用划痕愈合试验检测A549细胞的迁移水平,采用流式细胞术检测A549细胞的凋亡情况,同时采用实时荧光定量聚合酶链反应法和免疫印迹法分别检测A549细胞中MAPK、ERK、基质金属蛋白酶-9(MMP-9)、B细胞淋巴瘤2基因(Bcl-2)、胱天蛋白酶3(caspase-3)mRNA和蛋白表达水平。结果 随着丹参多糖质量浓度的增加,A549细胞增殖率显著降低(P <0.05);丹参多糖对A549细胞的IC50为7.82 mg/mL,高、中、低剂量组干预剂量分别为8,4,2 mg/mL。与对照组比较,抑制剂组,高、中、低剂量组细胞的迁移距离及MMP-9,MAPK,ERK,Bcl-2 mRNA和蛋白表达水平均显著降低(P <0.05),细胞凋亡率、caspase-3 mRNA和蛋白表达水平均显著升高(P <0.05);与抑制剂组比较,高、中、低剂量组细胞的迁移距离及MMP-9,MAPK,ERK,Bcl-2 mRNA和蛋白表达水平均显著升高(P <0.05),细胞凋亡率、caspase-3 mRNA和蛋白表达水平均显著降低(P <0.05),且随丹参多糖剂量的增加呈量效依赖关系(P <0.05)。结论 丹参多糖可能通过MAPK/ERK信号轴诱导A549细胞凋亡,抑制A549细胞增殖和迁移。

欧前胡素调节ERK/MAPK信号通路对肺结核大鼠炎症反应的影响

目的 探讨欧前胡素(Imp)调节细胞外调节蛋白激酶(ERK)/有丝分裂原激活蛋白激酶(MAPK)信号通路对肺结核大鼠炎症反应的影响。方法 64只大鼠随机分为对照组12只及造模组52只,造模组大鼠通过尾部注射结核杆菌方法建立肺结核大鼠模型,之后随机分为模型组、Imp低(Imp-L,25 mg/kg)、中(Imp-M,50 mg/kg)、高剂量(Imp-H,100 mg/kg)组、Imp-H+ERK特异性激活剂(EGF,100 mg/kg Imp+25 mg/kg EGF)组。干预结束后,主动脉采血,ELISA检测各组大鼠血清中白细胞介素-6(IL-6)、γ干扰素(IFN-γ)、环氧化酶-2(COX-2)水平;分离肺组织,HE、Tunel分别检测大鼠肺组织病理学变化及细胞凋亡情况;统计肺组织中结核杆菌菌落数;Western blot检测p-ERK1/2/ERK1/2、p38 MAPK表达水平。结果 与对照组相比,模型组肺组织严重病变,IL-6、IFN-γ、COX-2、细胞凋亡率、结核杆菌菌落数、p-ERK1/2/ERK1/2、p38 MAPK表达均显著增加(P<0.05);与模型组相比,Imp-L组、Imp-M组、Imp-H组病理损伤得到缓解,IL-6、IFN-γ、COX-2、细胞凋亡率、结核杆菌菌落数、p-ERK1/2/ERK1/2、p38 MAPK表达显著降低,以Imp-H组变化最为显著(P<0.05);与Imp-H组相比,Imp-H+EGF组病理损伤进一步加重,IL-6、IFN-γ、COX-2、细胞凋亡率、结核杆菌菌落数、p-ERK1/2/ERK1/2、p38 MAPK表达显著增加(P<0.05)。结论 Imp可降低肺结核炎症反应,与抑制ERK/MAPK信号通路的激活有关。

mTOR和ERK/MAPK信号通路调控自噬在孤独症发病中的作用

孤独症是一种以重复刻板样行为和社交缺陷为主要特征的神经发育障碍性疾病,发病率高的特点使其逐渐成为研究的热点。中国与西方国家孤独症的发病率相似,约为1%,位于儿童精神疾病的前列^([1])。目前认为孤独症由环境和遗传因素共同决定,病因复杂,具体机制尚不明确。随着研究的深入,自噬在孤独症发病机制中的作用受到广泛关注。

锌指蛋白-36缺陷抑制小鼠的成骨细胞分化:基于激活ERK/ MAPK通路

目的探究锌指蛋白-36(ZFP36)对成骨细胞分化的调控作用及机制。方法通过提取小鼠原代骨髓间充质干细胞,结合小鼠成骨细胞前体细胞系MC3T3-E1,在体外成骨分化诱导状态下观察Zfp36(编码ZFP36)的表达变化。通过干扰RNA技术构建Zfp36缺陷的细胞,观察成骨分化作用的改变。通过第二代转录组测序技术探究Zfp36缺陷细胞成骨分化过程中的转录组水平改变。通过ERK/MAPK信号抑制分子U0126验证Zfp36缺陷对成骨分化作用的调控机制。结果小鼠原代骨髓间充质细胞以及MC3T3-E2细胞中Zfp36表达在成骨分化0~14d过程中呈逐渐升高趋势,在第7天到达峰值时较第0天升高3.85倍(P<0.0001)。抑制上述细胞Zfp36的表达后,成骨分化过程中碱性磷酸酶染色及茜素红染色弱于对照组,成骨分化标志基因Alpl(P<0.01)、Sp7(P<0.001)、Bglap(P<0.01)、Ibsp(P<0.0001)表达显著减弱。转录本测序结果提示Zfp36缺陷细胞的下调基因富集到骨矿化相关基因集中,且与ERK信号相关。蛋白表达检测显示Zfp36缺陷细胞的磷酸化ERK蛋白比例较对照组升高2.1倍(P=0.0274)。通过分子化合物U0126抑制Zfp36缺陷细胞中被激活的ERK/MAPK信号,可观察到表型挽救现象,并且呈剂量依赖。Zfp36缺陷细胞在10μmol/L度U0126作用下碱性磷酸酶染色增强,成骨细胞分化标志基因Runx2(P<0.05)及Bglap(P<0.05)表达显著增高。结论ZFP36参与了小鼠成骨细胞的分化调控过程,Zfp36缺陷会引起ERK/MAPK信号通路的激活,进而抑制成骨细胞向骨细胞的分化。